2018-10-19 10:54:37

by Baolin Wang

[permalink] [raw]
Subject: [PATCH v5 1/6] dt-bindings: power: Introduce one property to present the battery internal resistance

The internal resistance of a battery is not a constant in its life cycle,
this varies over the age of the battery or temperature and so on. But we
just want use one constant battery internal resistance to estimate the
battery capacity. Thus this patch introduces one property to present
the battery factory internal resistance for battery information.

Signed-off-by: Baolin Wang <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
---
Changes from v4:
- None.

Changes from v3:
- Split binding into one separate patch.
- Add LinusW reviewed tag.

Changes from v2:
- Rename the property.
- Improve the commit message.

Changes from v1:
- New patch in v2.
---
.../devicetree/bindings/power/supply/battery.txt | 2 ++
1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/power/supply/battery.txt b/Documentation/devicetree/bindings/power/supply/battery.txt
index f4d3b4a..938d027 100644
--- a/Documentation/devicetree/bindings/power/supply/battery.txt
+++ b/Documentation/devicetree/bindings/power/supply/battery.txt
@@ -22,6 +22,7 @@ Optional Properties:
- charge-term-current-microamp: current for charge termination phase
- constant-charge-current-max-microamp: maximum constant input current
- constant-charge-voltage-max-microvolt: maximum constant input voltage
+ - factory-internal-resistance-micro-ohms: battery factory internal resistance

Battery properties are named, where possible, for the corresponding
elements in enum power_supply_property, defined in
@@ -42,6 +43,7 @@ Example:
charge-term-current-microamp = <128000>;
constant-charge-current-max-microamp = <900000>;
constant-charge-voltage-max-microvolt = <4200000>;
+ factory-internal-resistance-micro-ohms = <250000>;
};

charger: charger@11 {
--
1.7.9.5



2018-10-19 10:54:37

by Baolin Wang

[permalink] [raw]
Subject: [PATCH v5 2/6] power: supply: core: Add one field to present the battery internal resistance

Add one field for 'struct power_supply_battery_info' to present the battery
factory internal resistance.

Signed-off-by: Baolin Wang <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
---
Changes from v4:
- None.

Changes from v3:
- New patch in v3, which splits code into one separate patch.
- Add Linusw reviewed tag.
---
drivers/power/supply/power_supply_core.c | 3 +++
include/linux/power_supply.h | 1 +
2 files changed, 4 insertions(+)

diff --git a/drivers/power/supply/power_supply_core.c b/drivers/power/supply/power_supply_core.c
index e853618..307e0995 100644
--- a/drivers/power/supply/power_supply_core.c
+++ b/drivers/power/supply/power_supply_core.c
@@ -579,6 +579,7 @@ int power_supply_get_battery_info(struct power_supply *psy,
info->charge_term_current_ua = -EINVAL;
info->constant_charge_current_max_ua = -EINVAL;
info->constant_charge_voltage_max_uv = -EINVAL;
+ info->factory_internal_resistance_uohm = -EINVAL;

if (!psy->of_node) {
dev_warn(&psy->dev, "%s currently only supports devicetree\n",
@@ -616,6 +617,8 @@ int power_supply_get_battery_info(struct power_supply *psy,
&info->constant_charge_current_max_ua);
of_property_read_u32(battery_np, "constant_charge_voltage_max_microvolt",
&info->constant_charge_voltage_max_uv);
+ of_property_read_u32(battery_np, "factory-internal-resistance-micro-ohms",
+ &info->factory_internal_resistance_uohm);

return 0;
}
diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
index f807691..d089566 100644
--- a/include/linux/power_supply.h
+++ b/include/linux/power_supply.h
@@ -326,6 +326,7 @@ struct power_supply_battery_info {
int charge_term_current_ua; /* microAmps */
int constant_charge_current_max_ua; /* microAmps */
int constant_charge_voltage_max_uv; /* microVolts */
+ int factory_internal_resistance_uohm; /* microOhms */
};

extern struct atomic_notifier_head power_supply_notifier;
--
1.7.9.5


2018-10-19 10:54:37

by Baolin Wang

[permalink] [raw]
Subject: [PATCH v5 3/6] dt-bindings: power: Introduce properties to present the battery OCV capacity table

Some battery driver will use the open circuit voltage (OCV) value to look
up the corresponding battery capacity percent in one certain degree Celsius.
Thus this patch provides some battery properties to present the OCV table
temperatures and OCV capacity table values.

Suggested-by: Sebastian Reichel <[email protected]>
Signed-off-by: Baolin Wang <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
---
Changes from v4:
- Improve the description of ocv-capacity-table-n to make the order clear.

Changes from v3:
- Split binding into one separate patch.
- Rename ocv-capacity-table-temperatures to ocv-capacity-celsius.
- Add some words to specify the OCV's unit.

Changes from v2:
- Use type __be32 to calculate the table length.
- Update error messages.
- Add some helper functions.

Changes from v1:
- New patch in v2.
---
.../devicetree/bindings/power/supply/battery.txt | 15 +++++++++++++++
1 file changed, 15 insertions(+)

diff --git a/Documentation/devicetree/bindings/power/supply/battery.txt b/Documentation/devicetree/bindings/power/supply/battery.txt
index 938d027..89871ab 100644
--- a/Documentation/devicetree/bindings/power/supply/battery.txt
+++ b/Documentation/devicetree/bindings/power/supply/battery.txt
@@ -23,6 +23,17 @@ Optional Properties:
- constant-charge-current-max-microamp: maximum constant input current
- constant-charge-voltage-max-microvolt: maximum constant input voltage
- factory-internal-resistance-micro-ohms: battery factory internal resistance
+ - ocv-capacity-table-0: An array providing the open circuit voltage (OCV)
+ of the battery and corresponding battery capacity percent, which is used
+ to look up battery capacity according to current OCV value. And the open
+ circuit voltage unit is microvolt.
+ - ocv-capacity-table-1: Same as ocv-capacity-table-0
+ ......
+ - ocv-capacity-table-n: Same as ocv-capacity-table-0
+ - ocv-capacity-celsius: An array containing the temperature in degree Celsius,
+ for each of the battery capacity lookup table. The first temperature value
+ specifies the OCV table 0, and the second temperature value specifies the
+ OCV table 1, and so on.

Battery properties are named, where possible, for the corresponding
elements in enum power_supply_property, defined in
@@ -44,6 +55,10 @@ Example:
constant-charge-current-max-microamp = <900000>;
constant-charge-voltage-max-microvolt = <4200000>;
factory-internal-resistance-micro-ohms = <250000>;
+ ocv-capacity-celsius = <(-10) 0 10>;
+ ocv-capacity-table-0 = <4185000 100>, <4113000 95>, <4066000 90>, ...;
+ ocv-capacity-table-1 = <4200000 100>, <4185000 95>, <4113000 90>, ...;
+ ocv-capacity-table-2 = <4250000 100>, <4200000 95>, <4185000 90>, ...;
};

charger: charger@11 {
--
1.7.9.5


2018-10-19 10:54:37

by Baolin Wang

[permalink] [raw]
Subject: [PATCH v5 5/6] dt-bindings: power: Add Spreadtrum SC27XX fuel gauge unit documentation

This patch adds the binding documentation for Spreadtrum SC27XX series PMICs
fuel gauge unit device, which is used to calculate the battery capacity.

Signed-off-by: Baolin Wang <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
Reviewed-by: Rob Herring <[email protected]>
---
Changes from v4:
- None.

Changes from v3:
- Add reviewed tag from Rob.

Changes from v2:
- Add reviewed tag from Linus.

Changes from v1:
- Renamed GPIO property.
- Use standand battery properties instead of 'sprd,inner-resist' and
'sprd,ocv-cap-table'.
- Remove battery node's description.
---
.../devicetree/bindings/power/supply/sc27xx-fg.txt | 52 ++++++++++++++++++++
1 file changed, 52 insertions(+)
create mode 100644 Documentation/devicetree/bindings/power/supply/sc27xx-fg.txt

diff --git a/Documentation/devicetree/bindings/power/supply/sc27xx-fg.txt b/Documentation/devicetree/bindings/power/supply/sc27xx-fg.txt
new file mode 100644
index 0000000..98a2400
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/supply/sc27xx-fg.txt
@@ -0,0 +1,52 @@
+Spreadtrum SC27XX PMICs Fuel Gauge Unit Power Supply Bindings
+
+Required properties:
+- compatible: Should be one of the following:
+ "sprd,sc2720-fgu",
+ "sprd,sc2721-fgu",
+ "sprd,sc2723-fgu",
+ "sprd,sc2730-fgu",
+ "sprd,sc2731-fgu".
+- reg: The address offset of fuel gauge unit.
+- battery-detect-gpios: GPIO for battery detection.
+- io-channels: Specify the IIO ADC channel to get temperature.
+- io-channel-names: Should be "bat-temp".
+- monitored-battery: Phandle of battery characteristics devicetree node.
+ See Documentation/devicetree/bindings/power/supply/battery.txt
+
+Example:
+
+ bat: battery {
+ compatible = "simple-battery";
+ charge-full-design-microamp-hours = <1900000>;
+ constant-charge-voltage-max-microvolt = <4350000>;
+ ocv-capacity-celsius = <20>;
+ ocv-capacity-table-0 = <4185000 100>, <4113000 95>, <4066000 90>,
+ <4022000 85>, <3983000 80>, <3949000 75>,
+ <3917000 70>, <3889000 65>, <3864000 60>,
+ <3835000 55>, <3805000 50>, <3787000 45>,
+ <3777000 40>, <3773000 35>, <3770000 30>,
+ <3765000 25>, <3752000 20>, <3724000 15>,
+ <3680000 10>, <3605000 5>, <3400000 0>;
+ ......
+ };
+
+ sc2731_pmic: pmic@0 {
+ compatible = "sprd,sc2731";
+ reg = <0>;
+ spi-max-frequency = <26000000>;
+ interrupts = <GIC_SPI 31 IRQ_TYPE_LEVEL_HIGH>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ fgu@a00 {
+ compatible = "sprd,sc2731-fgu";
+ reg = <0xa00>;
+ battery-detect-gpios = <&pmic_eic 9 GPIO_ACTIVE_HIGH>;
+ io-channels = <&pmic_adc 5>;
+ io-channel-names = "bat-temp";
+ monitored-battery = <&bat>;
+ };
+ };
--
1.7.9.5


2018-10-19 10:54:37

by Baolin Wang

[permalink] [raw]
Subject: [PATCH v5 4/6] power: supply: core: Add some helpers to use the battery OCV capacity table

We have introduced some battery properties to present the OCV table
temperatures and OCV capacity table values. Thus this patch add OCV
temperature and OCV table for battery information, as well as providing
some helper functions to use the OCV capacity table for users.

Signed-off-by: Baolin Wang <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
---
Changes from v4:
- None.

Changes from v3:
- Split core modification into one separate patch.
- Rename ocv-capacity-table-temperatures to ocv-capacity-celsius.

Changes from v2:
- Use type __be32 to calculate the table length.
- Update error messages.
- Add some helper functions.

Changes from v1:
- New patch in v2.
---
drivers/power/supply/power_supply_core.c | 123 +++++++++++++++++++++++++++++-
include/linux/power_supply.h | 19 +++++
2 files changed, 141 insertions(+), 1 deletion(-)

diff --git a/drivers/power/supply/power_supply_core.c b/drivers/power/supply/power_supply_core.c
index 307e0995..58c4309 100644
--- a/drivers/power/supply/power_supply_core.c
+++ b/drivers/power/supply/power_supply_core.c
@@ -570,7 +570,7 @@ int power_supply_get_battery_info(struct power_supply *psy,
{
struct device_node *battery_np;
const char *value;
- int err;
+ int err, len, index;

info->energy_full_design_uwh = -EINVAL;
info->charge_full_design_uah = -EINVAL;
@@ -581,6 +581,12 @@ int power_supply_get_battery_info(struct power_supply *psy,
info->constant_charge_voltage_max_uv = -EINVAL;
info->factory_internal_resistance_uohm = -EINVAL;

+ for (index = 0; index < POWER_SUPPLY_OCV_TEMP_MAX; index++) {
+ info->ocv_table[index] = NULL;
+ info->ocv_temp[index] = -EINVAL;
+ info->ocv_table_size[index] = -EINVAL;
+ }
+
if (!psy->of_node) {
dev_warn(&psy->dev, "%s currently only supports devicetree\n",
__func__);
@@ -620,10 +626,125 @@ int power_supply_get_battery_info(struct power_supply *psy,
of_property_read_u32(battery_np, "factory-internal-resistance-micro-ohms",
&info->factory_internal_resistance_uohm);

+ len = of_property_count_u32_elems(battery_np, "ocv-capacity-celsius");
+ if (len < 0 && len != -EINVAL) {
+ return len;
+ } else if (len > POWER_SUPPLY_OCV_TEMP_MAX) {
+ dev_err(&psy->dev, "Too many temperature values\n");
+ return -EINVAL;
+ } else if (len > 0) {
+ of_property_read_u32_array(battery_np, "ocv-capacity-celsius",
+ info->ocv_temp, len);
+ }
+
+ for (index = 0; index < len; index++) {
+ struct power_supply_battery_ocv_table *table;
+ char *propname;
+ const __be32 *list;
+ int i, tab_len, size;
+
+ propname = kasprintf(GFP_KERNEL, "ocv-capacity-table-%d", index);
+ list = of_get_property(battery_np, propname, &size);
+ if (!list || !size) {
+ dev_err(&psy->dev, "failed to get %s\n", propname);
+ kfree(propname);
+ power_supply_put_battery_info(psy, info);
+ return -EINVAL;
+ }
+
+ kfree(propname);
+ tab_len = size / (2 * sizeof(__be32));
+ info->ocv_table_size[index] = tab_len;
+
+ table = info->ocv_table[index] =
+ devm_kzalloc(&psy->dev, tab_len * sizeof(*table),
+ GFP_KERNEL);
+ if (!info->ocv_table[index]) {
+ power_supply_put_battery_info(psy, info);
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < tab_len; i++) {
+ table[i].ocv = be32_to_cpu(*list++);
+ table[i].capacity = be32_to_cpu(*list++);
+ }
+ }
+
return 0;
}
EXPORT_SYMBOL_GPL(power_supply_get_battery_info);

+void power_supply_put_battery_info(struct power_supply *psy,
+ struct power_supply_battery_info *info)
+{
+ int i;
+
+ for (i = 0; i < POWER_SUPPLY_OCV_TEMP_MAX; i++)
+ kfree(info->ocv_table[i]);
+}
+EXPORT_SYMBOL_GPL(power_supply_put_battery_info);
+
+int power_supply_ocv2cap_simple(struct power_supply_battery_ocv_table *table,
+ int table_len, int ocv)
+{
+ int i, cap, tmp;
+
+ for (i = 0; i < table_len; i++)
+ if (ocv > table[i].ocv)
+ break;
+
+ if (i > 0 && i < table_len) {
+ tmp = (table[i - 1].capacity - table[i].capacity) *
+ (ocv - table[i].ocv);
+ tmp /= table[i - 1].ocv - table[i].ocv;
+ cap = tmp + table[i].capacity;
+ } else if (i == 0) {
+ cap = table[0].capacity;
+ } else {
+ cap = table[table_len - 1].capacity;
+ }
+
+ return cap;
+}
+EXPORT_SYMBOL_GPL(power_supply_ocv2cap_simple);
+
+struct power_supply_battery_ocv_table *
+power_supply_find_ocv2cap_table(struct power_supply_battery_info *info,
+ int temp, int *table_len)
+{
+ int best_temp_diff = INT_MAX, best_index = 0, temp_diff, i;
+
+ if (!info->ocv_table[0])
+ return NULL;
+
+ for (i = 0; i < POWER_SUPPLY_OCV_TEMP_MAX; i++) {
+ temp_diff = abs(info->ocv_temp[i] - temp);
+
+ if (temp_diff < best_temp_diff) {
+ best_temp_diff = temp_diff;
+ best_index = i;
+ }
+ }
+
+ *table_len = info->ocv_table_size[best_index];
+ return info->ocv_table[best_index];
+}
+EXPORT_SYMBOL_GPL(power_supply_find_ocv2cap_table);
+
+int power_supply_batinfo_ocv2cap(struct power_supply_battery_info *info,
+ int ocv, int temp)
+{
+ struct power_supply_battery_ocv_table *table;
+ int table_len;
+
+ table = power_supply_find_ocv2cap_table(info, temp, &table_len);
+ if (!table)
+ return -EINVAL;
+
+ return power_supply_ocv2cap_simple(table, table_len, ocv);
+}
+EXPORT_SYMBOL_GPL(power_supply_batinfo_ocv2cap);
+
int power_supply_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
index d089566..84fe93f 100644
--- a/include/linux/power_supply.h
+++ b/include/linux/power_supply.h
@@ -309,6 +309,13 @@ struct power_supply_info {
int use_for_apm;
};

+struct power_supply_battery_ocv_table {
+ int ocv; /* microVolts */
+ int capacity; /* percent */
+};
+
+#define POWER_SUPPLY_OCV_TEMP_MAX 20
+
/*
* This is the recommended struct to manage static battery parameters,
* populated by power_supply_get_battery_info(). Most platform drivers should
@@ -327,6 +334,9 @@ struct power_supply_battery_info {
int constant_charge_current_max_ua; /* microAmps */
int constant_charge_voltage_max_uv; /* microVolts */
int factory_internal_resistance_uohm; /* microOhms */
+ int ocv_temp[POWER_SUPPLY_OCV_TEMP_MAX];/* celsius */
+ struct power_supply_battery_ocv_table *ocv_table[POWER_SUPPLY_OCV_TEMP_MAX];
+ int ocv_table_size[POWER_SUPPLY_OCV_TEMP_MAX];
};

extern struct atomic_notifier_head power_supply_notifier;
@@ -350,6 +360,15 @@ extern struct power_supply *devm_power_supply_get_by_phandle(

extern int power_supply_get_battery_info(struct power_supply *psy,
struct power_supply_battery_info *info);
+extern void power_supply_put_battery_info(struct power_supply *psy,
+ struct power_supply_battery_info *info);
+extern int power_supply_ocv2cap_simple(struct power_supply_battery_ocv_table *table,
+ int table_len, int ocv);
+extern struct power_supply_battery_ocv_table *
+power_supply_find_ocv2cap_table(struct power_supply_battery_info *info,
+ int temp, int *table_len);
+extern int power_supply_batinfo_ocv2cap(struct power_supply_battery_info *info,
+ int ocv, int temp);
extern void power_supply_changed(struct power_supply *psy);
extern int power_supply_am_i_supplied(struct power_supply *psy);
extern int power_supply_set_input_current_limit_from_supplier(
--
1.7.9.5


2018-10-19 10:56:22

by Baolin Wang

[permalink] [raw]
Subject: [PATCH v5 6/6] power: supply: Add Spreadtrum SC27XX fuel gauge unit driver

This patch adds the Spreadtrum SC27XX serial PMICs fuel gauge support,
which is used to calculate the battery capacity.

Original-by: Yuanjiang Yu <[email protected]>
Signed-off-by: Baolin Wang <[email protected]>
Acked-by: Linus Walleij <[email protected]>
---
Changes from v4:
- None.

Changes from v3:
- None.

Changes from v2:
- Use core helper functions to look up OCV capacity table.
- Use device_property_read_u32() instead of of_property_read_u32().
- Add acked tag from Linus.

Changes from v1:
- Use battery standard properties to get internal resistance and ocv table.
- Change devm_gpiod_get_optional() to devm_gpiod_get().
- Add power_supply_changed() when detecting battery present change.
- Return micro volts for sc27xx_fgu_get_vbat_ocv().
---
drivers/power/supply/Kconfig | 7 +
drivers/power/supply/Makefile | 1 +
drivers/power/supply/sc27xx_fuel_gauge.c | 661 ++++++++++++++++++++++++++++++
3 files changed, 669 insertions(+)
create mode 100644 drivers/power/supply/sc27xx_fuel_gauge.c

diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index f27cf07..917f4b7 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -652,4 +652,11 @@ config CHARGER_SC2731
Say Y here to enable support for battery charging with SC2731
PMIC chips.

+config FUEL_GAUGE_SC27XX
+ tristate "Spreadtrum SC27XX fuel gauge driver"
+ depends on MFD_SC27XX_PMIC || COMPILE_TEST
+ help
+ Say Y here to enable support for fuel gauge with SC27XX
+ PMIC chips.
+
endif # POWER_SUPPLY
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index 767105b..b731c2a 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -86,3 +86,4 @@ obj-$(CONFIG_AXP288_FUEL_GAUGE) += axp288_fuel_gauge.o
obj-$(CONFIG_AXP288_CHARGER) += axp288_charger.o
obj-$(CONFIG_CHARGER_CROS_USBPD) += cros_usbpd-charger.o
obj-$(CONFIG_CHARGER_SC2731) += sc2731_charger.o
+obj-$(CONFIG_FUEL_GAUGE_SC27XX) += sc27xx_fuel_gauge.o
diff --git a/drivers/power/supply/sc27xx_fuel_gauge.c b/drivers/power/supply/sc27xx_fuel_gauge.c
new file mode 100644
index 0000000..1c0b856
--- /dev/null
+++ b/drivers/power/supply/sc27xx_fuel_gauge.c
@@ -0,0 +1,661 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Spreadtrum Communications Inc.
+
+#include <linux/gpio/consumer.h>
+#include <linux/iio/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/regmap.h>
+
+/* PMIC global control registers definition */
+#define SC27XX_MODULE_EN0 0xc08
+#define SC27XX_CLK_EN0 0xc18
+#define SC27XX_FGU_EN BIT(7)
+#define SC27XX_FGU_RTC_EN BIT(6)
+
+/* FGU registers definition */
+#define SC27XX_FGU_START 0x0
+#define SC27XX_FGU_CONFIG 0x4
+#define SC27XX_FGU_ADC_CONFIG 0x8
+#define SC27XX_FGU_STATUS 0xc
+#define SC27XX_FGU_INT_EN 0x10
+#define SC27XX_FGU_INT_CLR 0x14
+#define SC27XX_FGU_INT_STS 0x1c
+#define SC27XX_FGU_VOLTAGE 0x20
+#define SC27XX_FGU_OCV 0x24
+#define SC27XX_FGU_POCV 0x28
+#define SC27XX_FGU_CURRENT 0x2c
+#define SC27XX_FGU_CLBCNT_SETH 0x50
+#define SC27XX_FGU_CLBCNT_SETL 0x54
+#define SC27XX_FGU_CLBCNT_VALH 0x68
+#define SC27XX_FGU_CLBCNT_VALL 0x6c
+#define SC27XX_FGU_CLBCNT_QMAXL 0x74
+
+#define SC27XX_WRITE_SELCLB_EN BIT(0)
+#define SC27XX_FGU_CLBCNT_MASK GENMASK(15, 0)
+#define SC27XX_FGU_CLBCNT_SHIFT 16
+
+#define SC27XX_FGU_1000MV_ADC 686
+#define SC27XX_FGU_1000MA_ADC 1372
+#define SC27XX_FGU_CUR_BASIC_ADC 8192
+#define SC27XX_FGU_SAMPLE_HZ 2
+
+/*
+ * struct sc27xx_fgu_data: describe the FGU device
+ * @regmap: regmap for register access
+ * @dev: platform device
+ * @battery: battery power supply
+ * @base: the base offset for the controller
+ * @lock: protect the structure
+ * @gpiod: GPIO for battery detection
+ * @channel: IIO channel to get battery temperature
+ * @internal_resist: the battery internal resistance in mOhm
+ * @total_cap: the total capacity of the battery in mAh
+ * @init_cap: the initial capacity of the battery in mAh
+ * @init_clbcnt: the initial coulomb counter
+ * @max_volt: the maximum constant input voltage in millivolt
+ * @table_len: the capacity table length
+ * @cap_table: capacity table with corresponding ocv
+ */
+struct sc27xx_fgu_data {
+ struct regmap *regmap;
+ struct device *dev;
+ struct power_supply *battery;
+ u32 base;
+ struct mutex lock;
+ struct gpio_desc *gpiod;
+ struct iio_channel *channel;
+ bool bat_present;
+ int internal_resist;
+ int total_cap;
+ int init_cap;
+ int init_clbcnt;
+ int max_volt;
+ int table_len;
+ struct power_supply_battery_ocv_table *cap_table;
+};
+
+static const char * const sc27xx_charger_supply_name[] = {
+ "sc2731_charger",
+ "sc2720_charger",
+ "sc2721_charger",
+ "sc2723_charger",
+};
+
+static int sc27xx_fgu_adc_to_current(int adc)
+{
+ return (adc * 1000) / SC27XX_FGU_1000MA_ADC;
+}
+
+static int sc27xx_fgu_adc_to_voltage(int adc)
+{
+ return (adc * 1000) / SC27XX_FGU_1000MV_ADC;
+}
+
+/*
+ * When system boots on, we can not read battery capacity from coulomb
+ * registers, since now the coulomb registers are invalid. So we should
+ * calculate the battery open circuit voltage, and get current battery
+ * capacity according to the capacity table.
+ */
+static int sc27xx_fgu_get_boot_capacity(struct sc27xx_fgu_data *data, int *cap)
+{
+ int volt, cur, oci, ocv, ret;
+
+ /*
+ * After system booting on, the SC27XX_FGU_CLBCNT_QMAXL register saved
+ * the first sampled open circuit current.
+ */
+ ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_QMAXL,
+ &cur);
+ if (ret)
+ return ret;
+
+ cur <<= 1;
+ oci = sc27xx_fgu_adc_to_current(cur - SC27XX_FGU_CUR_BASIC_ADC);
+
+ /*
+ * Should get the OCV from SC27XX_FGU_POCV register at the system
+ * beginning. It is ADC values reading from registers which need to
+ * convert the corresponding voltage.
+ */
+ ret = regmap_read(data->regmap, data->base + SC27XX_FGU_POCV, &volt);
+ if (ret)
+ return ret;
+
+ volt = sc27xx_fgu_adc_to_voltage(volt);
+ ocv = volt - (oci * data->internal_resist) / 1000;
+
+ /*
+ * Parse the capacity table to look up the correct capacity percent
+ * according to current battery's corresponding OCV values.
+ */
+ *cap = power_supply_ocv2cap_simple(data->cap_table, data->table_len,
+ ocv);
+
+ return 0;
+}
+
+static int sc27xx_fgu_set_clbcnt(struct sc27xx_fgu_data *data, int clbcnt)
+{
+ int ret;
+
+ clbcnt *= SC27XX_FGU_SAMPLE_HZ;
+
+ ret = regmap_update_bits(data->regmap,
+ data->base + SC27XX_FGU_CLBCNT_SETL,
+ SC27XX_FGU_CLBCNT_MASK, clbcnt);
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(data->regmap,
+ data->base + SC27XX_FGU_CLBCNT_SETH,
+ SC27XX_FGU_CLBCNT_MASK,
+ clbcnt >> SC27XX_FGU_CLBCNT_SHIFT);
+ if (ret)
+ return ret;
+
+ return regmap_update_bits(data->regmap, data->base + SC27XX_FGU_START,
+ SC27XX_WRITE_SELCLB_EN,
+ SC27XX_WRITE_SELCLB_EN);
+}
+
+static int sc27xx_fgu_get_clbcnt(struct sc27xx_fgu_data *data, int *clb_cnt)
+{
+ int ccl, cch, ret;
+
+ ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALL,
+ &ccl);
+ if (ret)
+ return ret;
+
+ ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALH,
+ &cch);
+ if (ret)
+ return ret;
+
+ *clb_cnt = ccl & SC27XX_FGU_CLBCNT_MASK;
+ *clb_cnt |= (cch & SC27XX_FGU_CLBCNT_MASK) << SC27XX_FGU_CLBCNT_SHIFT;
+ *clb_cnt /= SC27XX_FGU_SAMPLE_HZ;
+
+ return 0;
+}
+
+static int sc27xx_fgu_get_capacity(struct sc27xx_fgu_data *data, int *cap)
+{
+ int ret, cur_clbcnt, delta_clbcnt, delta_cap, temp;
+
+ /* Get current coulomb counters firstly */
+ ret = sc27xx_fgu_get_clbcnt(data, &cur_clbcnt);
+ if (ret)
+ return ret;
+
+ delta_clbcnt = cur_clbcnt - data->init_clbcnt;
+
+ /*
+ * Convert coulomb counter to delta capacity (mAh), and set multiplier
+ * as 100 to improve the precision.
+ */
+ temp = DIV_ROUND_CLOSEST(delta_clbcnt, 360);
+ temp = sc27xx_fgu_adc_to_current(temp);
+
+ /*
+ * Convert to capacity percent of the battery total capacity,
+ * and multiplier is 100 too.
+ */
+ delta_cap = DIV_ROUND_CLOSEST(temp * 100, data->total_cap);
+ *cap = delta_cap + data->init_cap;
+
+ return 0;
+}
+
+static int sc27xx_fgu_get_vbat_vol(struct sc27xx_fgu_data *data, int *val)
+{
+ int ret, vol;
+
+ ret = regmap_read(data->regmap, data->base + SC27XX_FGU_VOLTAGE, &vol);
+ if (ret)
+ return ret;
+
+ /*
+ * It is ADC values reading from registers which need to convert to
+ * corresponding voltage values.
+ */
+ *val = sc27xx_fgu_adc_to_voltage(vol);
+
+ return 0;
+}
+
+static int sc27xx_fgu_get_current(struct sc27xx_fgu_data *data, int *val)
+{
+ int ret, cur;
+
+ ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CURRENT, &cur);
+ if (ret)
+ return ret;
+
+ /*
+ * It is ADC values reading from registers which need to convert to
+ * corresponding current values.
+ */
+ *val = sc27xx_fgu_adc_to_current(cur - SC27XX_FGU_CUR_BASIC_ADC);
+
+ return 0;
+}
+
+static int sc27xx_fgu_get_vbat_ocv(struct sc27xx_fgu_data *data, int *val)
+{
+ int vol, cur, ret;
+
+ ret = sc27xx_fgu_get_vbat_vol(data, &vol);
+ if (ret)
+ return ret;
+
+ ret = sc27xx_fgu_get_current(data, &cur);
+ if (ret)
+ return ret;
+
+ /* Return the battery OCV in micro volts. */
+ *val = vol * 1000 - cur * data->internal_resist;
+
+ return 0;
+}
+
+static int sc27xx_fgu_get_temp(struct sc27xx_fgu_data *data, int *temp)
+{
+ return iio_read_channel_processed(data->channel, temp);
+}
+
+static int sc27xx_fgu_get_health(struct sc27xx_fgu_data *data, int *health)
+{
+ int ret, vol;
+
+ ret = sc27xx_fgu_get_vbat_vol(data, &vol);
+ if (ret)
+ return ret;
+
+ if (vol > data->max_volt)
+ *health = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
+ else
+ *health = POWER_SUPPLY_HEALTH_GOOD;
+
+ return 0;
+}
+
+static int sc27xx_fgu_get_status(struct sc27xx_fgu_data *data, int *status)
+{
+ union power_supply_propval val;
+ struct power_supply *psy;
+ int i, ret = -EINVAL;
+
+ for (i = 0; i < ARRAY_SIZE(sc27xx_charger_supply_name); i++) {
+ psy = power_supply_get_by_name(sc27xx_charger_supply_name[i]);
+ if (!psy)
+ continue;
+
+ ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_STATUS,
+ &val);
+ power_supply_put(psy);
+ if (ret)
+ return ret;
+
+ *status = val.intval;
+ }
+
+ return ret;
+}
+
+static int sc27xx_fgu_get_property(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
+ int ret = 0;
+ int value;
+
+ mutex_lock(&data->lock);
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_STATUS:
+ ret = sc27xx_fgu_get_status(data, &value);
+ if (ret)
+ goto error;
+
+ val->intval = value;
+ break;
+
+ case POWER_SUPPLY_PROP_HEALTH:
+ ret = sc27xx_fgu_get_health(data, &value);
+ if (ret)
+ goto error;
+
+ val->intval = value;
+ break;
+
+ case POWER_SUPPLY_PROP_PRESENT:
+ val->intval = data->bat_present;
+ break;
+
+ case POWER_SUPPLY_PROP_TEMP:
+ ret = sc27xx_fgu_get_temp(data, &value);
+ if (ret)
+ goto error;
+
+ val->intval = value;
+ break;
+
+ case POWER_SUPPLY_PROP_TECHNOLOGY:
+ val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
+ break;
+
+ case POWER_SUPPLY_PROP_CAPACITY:
+ ret = sc27xx_fgu_get_capacity(data, &value);
+ if (ret)
+ goto error;
+
+ val->intval = value;
+ break;
+
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ ret = sc27xx_fgu_get_vbat_vol(data, &value);
+ if (ret)
+ goto error;
+
+ val->intval = value * 1000;
+ break;
+
+ case POWER_SUPPLY_PROP_VOLTAGE_OCV:
+ ret = sc27xx_fgu_get_vbat_ocv(data, &value);
+ if (ret)
+ goto error;
+
+ val->intval = value;
+ break;
+
+ case POWER_SUPPLY_PROP_CURRENT_NOW:
+ case POWER_SUPPLY_PROP_CURRENT_AVG:
+ ret = sc27xx_fgu_get_current(data, &value);
+ if (ret)
+ goto error;
+
+ val->intval = value * 1000;
+ break;
+
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+error:
+ mutex_unlock(&data->lock);
+ return ret;
+}
+
+static void sc27xx_fgu_external_power_changed(struct power_supply *psy)
+{
+ struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
+
+ power_supply_changed(data->battery);
+}
+
+static enum power_supply_property sc27xx_fgu_props[] = {
+ POWER_SUPPLY_PROP_STATUS,
+ POWER_SUPPLY_PROP_HEALTH,
+ POWER_SUPPLY_PROP_PRESENT,
+ POWER_SUPPLY_PROP_TEMP,
+ POWER_SUPPLY_PROP_TECHNOLOGY,
+ POWER_SUPPLY_PROP_CAPACITY,
+ POWER_SUPPLY_PROP_VOLTAGE_NOW,
+ POWER_SUPPLY_PROP_VOLTAGE_OCV,
+ POWER_SUPPLY_PROP_CURRENT_NOW,
+ POWER_SUPPLY_PROP_CURRENT_AVG,
+};
+
+static const struct power_supply_desc sc27xx_fgu_desc = {
+ .name = "sc27xx-fgu",
+ .type = POWER_SUPPLY_TYPE_BATTERY,
+ .properties = sc27xx_fgu_props,
+ .num_properties = ARRAY_SIZE(sc27xx_fgu_props),
+ .get_property = sc27xx_fgu_get_property,
+ .external_power_changed = sc27xx_fgu_external_power_changed,
+};
+
+static irqreturn_t sc27xx_fgu_bat_detection(int irq, void *dev_id)
+{
+ struct sc27xx_fgu_data *data = dev_id;
+ int state;
+
+ mutex_lock(&data->lock);
+
+ state = gpiod_get_value_cansleep(data->gpiod);
+ if (state < 0) {
+ dev_err(data->dev, "failed to get gpio state\n");
+ mutex_unlock(&data->lock);
+ return IRQ_RETVAL(state);
+ }
+
+ data->bat_present = !!state;
+
+ mutex_unlock(&data->lock);
+
+ power_supply_changed(data->battery);
+ return IRQ_HANDLED;
+}
+
+static void sc27xx_fgu_disable(void *_data)
+{
+ struct sc27xx_fgu_data *data = _data;
+
+ regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
+ regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
+}
+
+static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int capacity)
+{
+ /*
+ * Get current capacity (mAh) = battery total capacity (mAh) *
+ * current capacity percent (capacity / 100).
+ */
+ int cur_cap = DIV_ROUND_CLOSEST(data->total_cap * capacity, 100);
+
+ /*
+ * Convert current capacity (mAh) to coulomb counter according to the
+ * formula: 1 mAh =3.6 coulomb.
+ */
+ return DIV_ROUND_CLOSEST(cur_cap * 36, 10);
+}
+
+static int sc27xx_fgu_hw_init(struct sc27xx_fgu_data *data)
+{
+ struct power_supply_battery_info info = { };
+ struct power_supply_battery_ocv_table *table;
+ int ret, i;
+
+ ret = power_supply_get_battery_info(data->battery, &info);
+ if (ret) {
+ dev_err(data->dev, "failed to get battery information\n");
+ return ret;
+ }
+
+ data->total_cap = info.charge_full_design_uah / 1000;
+ data->max_volt = info.constant_charge_voltage_max_uv / 1000;
+ data->internal_resist = info.factory_internal_resistance_uohm / 1000;
+
+ /*
+ * For SC27XX fuel gauge device, we only use one ocv-capacity
+ * table in normal temperature 20 Celsius.
+ */
+ table = power_supply_find_ocv2cap_table(&info, 20, &data->table_len);
+ if (!table)
+ return -EINVAL;
+
+ data->cap_table = devm_kzalloc(data->dev,
+ data->table_len * sizeof(*table),
+ GFP_KERNEL);
+ if (!data->cap_table) {
+ power_supply_put_battery_info(data->battery, &info);
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < data->table_len; i++) {
+ data->cap_table[i].ocv = table[i].ocv / 1000;
+ data->cap_table[i].capacity = table[i].capacity;
+ }
+
+ power_supply_put_battery_info(data->battery, &info);
+
+ /* Enable the FGU module */
+ ret = regmap_update_bits(data->regmap, SC27XX_MODULE_EN0,
+ SC27XX_FGU_EN, SC27XX_FGU_EN);
+ if (ret) {
+ dev_err(data->dev, "failed to enable fgu\n");
+ return ret;
+ }
+
+ /* Enable the FGU RTC clock to make it work */
+ ret = regmap_update_bits(data->regmap, SC27XX_CLK_EN0,
+ SC27XX_FGU_RTC_EN, SC27XX_FGU_RTC_EN);
+ if (ret) {
+ dev_err(data->dev, "failed to enable fgu RTC clock\n");
+ goto disable_fgu;
+ }
+
+ /*
+ * Get the boot battery capacity when system powers on, which is used to
+ * initialize the coulomb counter. After that, we can read the coulomb
+ * counter to measure the battery capacity.
+ */
+ ret = sc27xx_fgu_get_boot_capacity(data, &data->init_cap);
+ if (ret) {
+ dev_err(data->dev, "failed to get boot capacity\n");
+ goto disable_clk;
+ }
+
+ /*
+ * Convert battery capacity to the corresponding initial coulomb counter
+ * and set into coulomb counter registers.
+ */
+ data->init_clbcnt = sc27xx_fgu_cap_to_clbcnt(data, data->init_cap);
+ ret = sc27xx_fgu_set_clbcnt(data, data->init_clbcnt);
+ if (ret) {
+ dev_err(data->dev, "failed to initialize coulomb counter\n");
+ goto disable_clk;
+ }
+
+ return 0;
+
+disable_clk:
+ regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
+disable_fgu:
+ regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
+
+ return ret;
+}
+
+static int sc27xx_fgu_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct power_supply_config fgu_cfg = { };
+ struct sc27xx_fgu_data *data;
+ int ret, irq;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!data->regmap) {
+ dev_err(&pdev->dev, "failed to get regmap\n");
+ return -ENODEV;
+ }
+
+ ret = device_property_read_u32(&pdev->dev, "reg", &data->base);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to get fgu address\n");
+ return ret;
+ }
+
+ data->channel = devm_iio_channel_get(&pdev->dev, "bat-temp");
+ if (IS_ERR(data->channel)) {
+ dev_err(&pdev->dev, "failed to get IIO channel\n");
+ return PTR_ERR(data->channel);
+ }
+
+ data->gpiod = devm_gpiod_get(&pdev->dev, "bat-detect", GPIOD_IN);
+ if (IS_ERR(data->gpiod)) {
+ dev_err(&pdev->dev, "failed to get battery detection GPIO\n");
+ return PTR_ERR(data->gpiod);
+ }
+
+ ret = gpiod_get_value_cansleep(data->gpiod);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to get gpio state\n");
+ return ret;
+ }
+
+ data->bat_present = !!ret;
+ mutex_init(&data->lock);
+ data->dev = &pdev->dev;
+
+ fgu_cfg.drv_data = data;
+ fgu_cfg.of_node = np;
+ data->battery = devm_power_supply_register(&pdev->dev, &sc27xx_fgu_desc,
+ &fgu_cfg);
+ if (IS_ERR(data->battery)) {
+ dev_err(&pdev->dev, "failed to register power supply\n");
+ return PTR_ERR(data->battery);
+ }
+
+ ret = sc27xx_fgu_hw_init(data);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to initialize fgu hardware\n");
+ return ret;
+ }
+
+ ret = devm_add_action(&pdev->dev, sc27xx_fgu_disable, data);
+ if (ret) {
+ sc27xx_fgu_disable(data);
+ dev_err(&pdev->dev, "failed to add fgu disable action\n");
+ return ret;
+ }
+
+ irq = gpiod_to_irq(data->gpiod);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "failed to translate GPIO to IRQ\n");
+ return irq;
+ }
+
+ ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
+ sc27xx_fgu_bat_detection,
+ IRQF_ONESHOT | IRQF_TRIGGER_RISING |
+ IRQF_TRIGGER_FALLING,
+ pdev->name, data);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to request IRQ\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id sc27xx_fgu_of_match[] = {
+ { .compatible = "sprd,sc2731-fgu", },
+ { }
+};
+
+static struct platform_driver sc27xx_fgu_driver = {
+ .probe = sc27xx_fgu_probe,
+ .driver = {
+ .name = "sc27xx-fgu",
+ .of_match_table = sc27xx_fgu_of_match,
+ }
+};
+
+module_platform_driver(sc27xx_fgu_driver);
+
+MODULE_DESCRIPTION("Spreadtrum SC27XX PMICs Fual Gauge Unit Driver");
+MODULE_LICENSE("GPL v2");
--
1.7.9.5


2018-10-21 19:28:08

by Sebastian Reichel

[permalink] [raw]
Subject: Re: [PATCH v5 2/6] power: supply: core: Add one field to present the battery internal resistance

Hi,

On Fri, Oct 19, 2018 at 06:53:11PM +0800, Baolin Wang wrote:
> Add one field for 'struct power_supply_battery_info' to present the battery
> factory internal resistance.
>
> Signed-off-by: Baolin Wang <[email protected]>
> Reviewed-by: Linus Walleij <[email protected]>
> ---

Looks good to me.

-- Sebastian

> Changes from v4:
> - None.
>
> Changes from v3:
> - New patch in v3, which splits code into one separate patch.
> - Add Linusw reviewed tag.
> ---
> drivers/power/supply/power_supply_core.c | 3 +++
> include/linux/power_supply.h | 1 +
> 2 files changed, 4 insertions(+)
>
> diff --git a/drivers/power/supply/power_supply_core.c b/drivers/power/supply/power_supply_core.c
> index e853618..307e0995 100644
> --- a/drivers/power/supply/power_supply_core.c
> +++ b/drivers/power/supply/power_supply_core.c
> @@ -579,6 +579,7 @@ int power_supply_get_battery_info(struct power_supply *psy,
> info->charge_term_current_ua = -EINVAL;
> info->constant_charge_current_max_ua = -EINVAL;
> info->constant_charge_voltage_max_uv = -EINVAL;
> + info->factory_internal_resistance_uohm = -EINVAL;
>
> if (!psy->of_node) {
> dev_warn(&psy->dev, "%s currently only supports devicetree\n",
> @@ -616,6 +617,8 @@ int power_supply_get_battery_info(struct power_supply *psy,
> &info->constant_charge_current_max_ua);
> of_property_read_u32(battery_np, "constant_charge_voltage_max_microvolt",
> &info->constant_charge_voltage_max_uv);
> + of_property_read_u32(battery_np, "factory-internal-resistance-micro-ohms",
> + &info->factory_internal_resistance_uohm);
>
> return 0;
> }
> diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
> index f807691..d089566 100644
> --- a/include/linux/power_supply.h
> +++ b/include/linux/power_supply.h
> @@ -326,6 +326,7 @@ struct power_supply_battery_info {
> int charge_term_current_ua; /* microAmps */
> int constant_charge_current_max_ua; /* microAmps */
> int constant_charge_voltage_max_uv; /* microVolts */
> + int factory_internal_resistance_uohm; /* microOhms */
> };
>
> extern struct atomic_notifier_head power_supply_notifier;
> --
> 1.7.9.5
>


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2018-10-21 19:28:08

by Sebastian Reichel

[permalink] [raw]
Subject: Re: [PATCH v5 4/6] power: supply: core: Add some helpers to use the battery OCV capacity table

Hi,

On Fri, Oct 19, 2018 at 06:53:13PM +0800, Baolin Wang wrote:
> We have introduced some battery properties to present the OCV table
> temperatures and OCV capacity table values. Thus this patch add OCV
> temperature and OCV table for battery information, as well as providing
> some helper functions to use the OCV capacity table for users.
>
> Signed-off-by: Baolin Wang <[email protected]>
> Reviewed-by: Linus Walleij <[email protected]>
> ---

Looks good to me.

-- Sebastian

> Changes from v4:
> - None.
>
> Changes from v3:
> - Split core modification into one separate patch.
> - Rename ocv-capacity-table-temperatures to ocv-capacity-celsius.
>
> Changes from v2:
> - Use type __be32 to calculate the table length.
> - Update error messages.
> - Add some helper functions.
>
> Changes from v1:
> - New patch in v2.
> ---
> drivers/power/supply/power_supply_core.c | 123 +++++++++++++++++++++++++++++-
> include/linux/power_supply.h | 19 +++++
> 2 files changed, 141 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/power/supply/power_supply_core.c b/drivers/power/supply/power_supply_core.c
> index 307e0995..58c4309 100644
> --- a/drivers/power/supply/power_supply_core.c
> +++ b/drivers/power/supply/power_supply_core.c
> @@ -570,7 +570,7 @@ int power_supply_get_battery_info(struct power_supply *psy,
> {
> struct device_node *battery_np;
> const char *value;
> - int err;
> + int err, len, index;
>
> info->energy_full_design_uwh = -EINVAL;
> info->charge_full_design_uah = -EINVAL;
> @@ -581,6 +581,12 @@ int power_supply_get_battery_info(struct power_supply *psy,
> info->constant_charge_voltage_max_uv = -EINVAL;
> info->factory_internal_resistance_uohm = -EINVAL;
>
> + for (index = 0; index < POWER_SUPPLY_OCV_TEMP_MAX; index++) {
> + info->ocv_table[index] = NULL;
> + info->ocv_temp[index] = -EINVAL;
> + info->ocv_table_size[index] = -EINVAL;
> + }
> +
> if (!psy->of_node) {
> dev_warn(&psy->dev, "%s currently only supports devicetree\n",
> __func__);
> @@ -620,10 +626,125 @@ int power_supply_get_battery_info(struct power_supply *psy,
> of_property_read_u32(battery_np, "factory-internal-resistance-micro-ohms",
> &info->factory_internal_resistance_uohm);
>
> + len = of_property_count_u32_elems(battery_np, "ocv-capacity-celsius");
> + if (len < 0 && len != -EINVAL) {
> + return len;
> + } else if (len > POWER_SUPPLY_OCV_TEMP_MAX) {
> + dev_err(&psy->dev, "Too many temperature values\n");
> + return -EINVAL;
> + } else if (len > 0) {
> + of_property_read_u32_array(battery_np, "ocv-capacity-celsius",
> + info->ocv_temp, len);
> + }
> +
> + for (index = 0; index < len; index++) {
> + struct power_supply_battery_ocv_table *table;
> + char *propname;
> + const __be32 *list;
> + int i, tab_len, size;
> +
> + propname = kasprintf(GFP_KERNEL, "ocv-capacity-table-%d", index);
> + list = of_get_property(battery_np, propname, &size);
> + if (!list || !size) {
> + dev_err(&psy->dev, "failed to get %s\n", propname);
> + kfree(propname);
> + power_supply_put_battery_info(psy, info);
> + return -EINVAL;
> + }
> +
> + kfree(propname);
> + tab_len = size / (2 * sizeof(__be32));
> + info->ocv_table_size[index] = tab_len;
> +
> + table = info->ocv_table[index] =
> + devm_kzalloc(&psy->dev, tab_len * sizeof(*table),
> + GFP_KERNEL);
> + if (!info->ocv_table[index]) {
> + power_supply_put_battery_info(psy, info);
> + return -ENOMEM;
> + }
> +
> + for (i = 0; i < tab_len; i++) {
> + table[i].ocv = be32_to_cpu(*list++);
> + table[i].capacity = be32_to_cpu(*list++);
> + }
> + }
> +
> return 0;
> }
> EXPORT_SYMBOL_GPL(power_supply_get_battery_info);
>
> +void power_supply_put_battery_info(struct power_supply *psy,
> + struct power_supply_battery_info *info)
> +{
> + int i;
> +
> + for (i = 0; i < POWER_SUPPLY_OCV_TEMP_MAX; i++)
> + kfree(info->ocv_table[i]);
> +}
> +EXPORT_SYMBOL_GPL(power_supply_put_battery_info);
> +
> +int power_supply_ocv2cap_simple(struct power_supply_battery_ocv_table *table,
> + int table_len, int ocv)
> +{
> + int i, cap, tmp;
> +
> + for (i = 0; i < table_len; i++)
> + if (ocv > table[i].ocv)
> + break;
> +
> + if (i > 0 && i < table_len) {
> + tmp = (table[i - 1].capacity - table[i].capacity) *
> + (ocv - table[i].ocv);
> + tmp /= table[i - 1].ocv - table[i].ocv;
> + cap = tmp + table[i].capacity;
> + } else if (i == 0) {
> + cap = table[0].capacity;
> + } else {
> + cap = table[table_len - 1].capacity;
> + }
> +
> + return cap;
> +}
> +EXPORT_SYMBOL_GPL(power_supply_ocv2cap_simple);
> +
> +struct power_supply_battery_ocv_table *
> +power_supply_find_ocv2cap_table(struct power_supply_battery_info *info,
> + int temp, int *table_len)
> +{
> + int best_temp_diff = INT_MAX, best_index = 0, temp_diff, i;
> +
> + if (!info->ocv_table[0])
> + return NULL;
> +
> + for (i = 0; i < POWER_SUPPLY_OCV_TEMP_MAX; i++) {
> + temp_diff = abs(info->ocv_temp[i] - temp);
> +
> + if (temp_diff < best_temp_diff) {
> + best_temp_diff = temp_diff;
> + best_index = i;
> + }
> + }
> +
> + *table_len = info->ocv_table_size[best_index];
> + return info->ocv_table[best_index];
> +}
> +EXPORT_SYMBOL_GPL(power_supply_find_ocv2cap_table);
> +
> +int power_supply_batinfo_ocv2cap(struct power_supply_battery_info *info,
> + int ocv, int temp)
> +{
> + struct power_supply_battery_ocv_table *table;
> + int table_len;
> +
> + table = power_supply_find_ocv2cap_table(info, temp, &table_len);
> + if (!table)
> + return -EINVAL;
> +
> + return power_supply_ocv2cap_simple(table, table_len, ocv);
> +}
> +EXPORT_SYMBOL_GPL(power_supply_batinfo_ocv2cap);
> +
> int power_supply_get_property(struct power_supply *psy,
> enum power_supply_property psp,
> union power_supply_propval *val)
> diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
> index d089566..84fe93f 100644
> --- a/include/linux/power_supply.h
> +++ b/include/linux/power_supply.h
> @@ -309,6 +309,13 @@ struct power_supply_info {
> int use_for_apm;
> };
>
> +struct power_supply_battery_ocv_table {
> + int ocv; /* microVolts */
> + int capacity; /* percent */
> +};
> +
> +#define POWER_SUPPLY_OCV_TEMP_MAX 20
> +
> /*
> * This is the recommended struct to manage static battery parameters,
> * populated by power_supply_get_battery_info(). Most platform drivers should
> @@ -327,6 +334,9 @@ struct power_supply_battery_info {
> int constant_charge_current_max_ua; /* microAmps */
> int constant_charge_voltage_max_uv; /* microVolts */
> int factory_internal_resistance_uohm; /* microOhms */
> + int ocv_temp[POWER_SUPPLY_OCV_TEMP_MAX];/* celsius */
> + struct power_supply_battery_ocv_table *ocv_table[POWER_SUPPLY_OCV_TEMP_MAX];
> + int ocv_table_size[POWER_SUPPLY_OCV_TEMP_MAX];
> };
>
> extern struct atomic_notifier_head power_supply_notifier;
> @@ -350,6 +360,15 @@ extern struct power_supply *devm_power_supply_get_by_phandle(
>
> extern int power_supply_get_battery_info(struct power_supply *psy,
> struct power_supply_battery_info *info);
> +extern void power_supply_put_battery_info(struct power_supply *psy,
> + struct power_supply_battery_info *info);
> +extern int power_supply_ocv2cap_simple(struct power_supply_battery_ocv_table *table,
> + int table_len, int ocv);
> +extern struct power_supply_battery_ocv_table *
> +power_supply_find_ocv2cap_table(struct power_supply_battery_info *info,
> + int temp, int *table_len);
> +extern int power_supply_batinfo_ocv2cap(struct power_supply_battery_info *info,
> + int ocv, int temp);
> extern void power_supply_changed(struct power_supply *psy);
> extern int power_supply_am_i_supplied(struct power_supply *psy);
> extern int power_supply_set_input_current_limit_from_supplier(
> --
> 1.7.9.5
>


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2018-10-21 19:28:12

by Sebastian Reichel

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Subject: Re: [PATCH v5 3/6] dt-bindings: power: Introduce properties to present the battery OCV capacity table

Hi,

On Fri, Oct 19, 2018 at 06:53:12PM +0800, Baolin Wang wrote:
> Some battery driver will use the open circuit voltage (OCV) value to look
> up the corresponding battery capacity percent in one certain degree Celsius.
> Thus this patch provides some battery properties to present the OCV table
> temperatures and OCV capacity table values.
>
> Suggested-by: Sebastian Reichel <[email protected]>
> Signed-off-by: Baolin Wang <[email protected]>
> Reviewed-by: Linus Walleij <[email protected]>
> ---

Looks good to me.

-- Sebastian

> Changes from v4:
> - Improve the description of ocv-capacity-table-n to make the order clear.
>
> Changes from v3:
> - Split binding into one separate patch.
> - Rename ocv-capacity-table-temperatures to ocv-capacity-celsius.
> - Add some words to specify the OCV's unit.
>
> Changes from v2:
> - Use type __be32 to calculate the table length.
> - Update error messages.
> - Add some helper functions.
>
> Changes from v1:
> - New patch in v2.
> ---
> .../devicetree/bindings/power/supply/battery.txt | 15 +++++++++++++++
> 1 file changed, 15 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/power/supply/battery.txt b/Documentation/devicetree/bindings/power/supply/battery.txt
> index 938d027..89871ab 100644
> --- a/Documentation/devicetree/bindings/power/supply/battery.txt
> +++ b/Documentation/devicetree/bindings/power/supply/battery.txt
> @@ -23,6 +23,17 @@ Optional Properties:
> - constant-charge-current-max-microamp: maximum constant input current
> - constant-charge-voltage-max-microvolt: maximum constant input voltage
> - factory-internal-resistance-micro-ohms: battery factory internal resistance
> + - ocv-capacity-table-0: An array providing the open circuit voltage (OCV)
> + of the battery and corresponding battery capacity percent, which is used
> + to look up battery capacity according to current OCV value. And the open
> + circuit voltage unit is microvolt.
> + - ocv-capacity-table-1: Same as ocv-capacity-table-0
> + ......
> + - ocv-capacity-table-n: Same as ocv-capacity-table-0
> + - ocv-capacity-celsius: An array containing the temperature in degree Celsius,
> + for each of the battery capacity lookup table. The first temperature value
> + specifies the OCV table 0, and the second temperature value specifies the
> + OCV table 1, and so on.
>
> Battery properties are named, where possible, for the corresponding
> elements in enum power_supply_property, defined in
> @@ -44,6 +55,10 @@ Example:
> constant-charge-current-max-microamp = <900000>;
> constant-charge-voltage-max-microvolt = <4200000>;
> factory-internal-resistance-micro-ohms = <250000>;
> + ocv-capacity-celsius = <(-10) 0 10>;
> + ocv-capacity-table-0 = <4185000 100>, <4113000 95>, <4066000 90>, ...;
> + ocv-capacity-table-1 = <4200000 100>, <4185000 95>, <4113000 90>, ...;
> + ocv-capacity-table-2 = <4250000 100>, <4200000 95>, <4185000 90>, ...;
> };
>
> charger: charger@11 {
> --
> 1.7.9.5
>


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2018-10-21 19:30:09

by Sebastian Reichel

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Subject: Re: [PATCH v5 1/6] dt-bindings: power: Introduce one property to present the battery internal resistance

Hi,

On Fri, Oct 19, 2018 at 06:53:10PM +0800, Baolin Wang wrote:
> The internal resistance of a battery is not a constant in its life cycle,
> this varies over the age of the battery or temperature and so on. But we
> just want use one constant battery internal resistance to estimate the
> battery capacity. Thus this patch introduces one property to present
> the battery factory internal resistance for battery information.
>
> Signed-off-by: Baolin Wang <[email protected]>
> Reviewed-by: Linus Walleij <[email protected]>
> ---

Looks good to me.

-- Sebastian

> Changes from v4:
> - None.
>
> Changes from v3:
> - Split binding into one separate patch.
> - Add LinusW reviewed tag.
>
> Changes from v2:
> - Rename the property.
> - Improve the commit message.
>
> Changes from v1:
> - New patch in v2.
> ---
> .../devicetree/bindings/power/supply/battery.txt | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/power/supply/battery.txt b/Documentation/devicetree/bindings/power/supply/battery.txt
> index f4d3b4a..938d027 100644
> --- a/Documentation/devicetree/bindings/power/supply/battery.txt
> +++ b/Documentation/devicetree/bindings/power/supply/battery.txt
> @@ -22,6 +22,7 @@ Optional Properties:
> - charge-term-current-microamp: current for charge termination phase
> - constant-charge-current-max-microamp: maximum constant input current
> - constant-charge-voltage-max-microvolt: maximum constant input voltage
> + - factory-internal-resistance-micro-ohms: battery factory internal resistance
>
> Battery properties are named, where possible, for the corresponding
> elements in enum power_supply_property, defined in
> @@ -42,6 +43,7 @@ Example:
> charge-term-current-microamp = <128000>;
> constant-charge-current-max-microamp = <900000>;
> constant-charge-voltage-max-microvolt = <4200000>;
> + factory-internal-resistance-micro-ohms = <250000>;
> };
>
> charger: charger@11 {
> --
> 1.7.9.5
>


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2018-10-21 19:30:45

by Sebastian Reichel

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Subject: Re: [PATCH v5 6/6] power: supply: Add Spreadtrum SC27XX fuel gauge unit driver

Hi,

On Fri, Oct 19, 2018 at 06:53:15PM +0800, Baolin Wang wrote:
> This patch adds the Spreadtrum SC27XX serial PMICs fuel gauge support,
> which is used to calculate the battery capacity.
>
> Original-by: Yuanjiang Yu <[email protected]>
> Signed-off-by: Baolin Wang <[email protected]>
> Acked-by: Linus Walleij <[email protected]>
> ---

Looks mostly good. I have a few comments still. My plan is to merge
this early after the merge window, if the final version is finished
at this point.

> Changes from v4:
> - None.
>
> Changes from v3:
> - None.
>
> Changes from v2:
> - Use core helper functions to look up OCV capacity table.
> - Use device_property_read_u32() instead of of_property_read_u32().
> - Add acked tag from Linus.
>
> Changes from v1:
> - Use battery standard properties to get internal resistance and ocv table.
> - Change devm_gpiod_get_optional() to devm_gpiod_get().
> - Add power_supply_changed() when detecting battery present change.
> - Return micro volts for sc27xx_fgu_get_vbat_ocv().
> ---
> drivers/power/supply/Kconfig | 7 +
> drivers/power/supply/Makefile | 1 +
> drivers/power/supply/sc27xx_fuel_gauge.c | 661 ++++++++++++++++++++++++++++++
> 3 files changed, 669 insertions(+)
> create mode 100644 drivers/power/supply/sc27xx_fuel_gauge.c
>
> diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
> index f27cf07..917f4b7 100644
> --- a/drivers/power/supply/Kconfig
> +++ b/drivers/power/supply/Kconfig
> @@ -652,4 +652,11 @@ config CHARGER_SC2731
> Say Y here to enable support for battery charging with SC2731
> PMIC chips.
>
> +config FUEL_GAUGE_SC27XX
> + tristate "Spreadtrum SC27XX fuel gauge driver"
> + depends on MFD_SC27XX_PMIC || COMPILE_TEST
> + help
> + Say Y here to enable support for fuel gauge with SC27XX
> + PMIC chips.
> +
> endif # POWER_SUPPLY
> diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
> index 767105b..b731c2a 100644
> --- a/drivers/power/supply/Makefile
> +++ b/drivers/power/supply/Makefile
> @@ -86,3 +86,4 @@ obj-$(CONFIG_AXP288_FUEL_GAUGE) += axp288_fuel_gauge.o
> obj-$(CONFIG_AXP288_CHARGER) += axp288_charger.o
> obj-$(CONFIG_CHARGER_CROS_USBPD) += cros_usbpd-charger.o
> obj-$(CONFIG_CHARGER_SC2731) += sc2731_charger.o
> +obj-$(CONFIG_FUEL_GAUGE_SC27XX) += sc27xx_fuel_gauge.o
> diff --git a/drivers/power/supply/sc27xx_fuel_gauge.c b/drivers/power/supply/sc27xx_fuel_gauge.c
> new file mode 100644
> index 0000000..1c0b856
> --- /dev/null
> +++ b/drivers/power/supply/sc27xx_fuel_gauge.c
> @@ -0,0 +1,661 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (C) 2018 Spreadtrum Communications Inc.
> +
> +#include <linux/gpio/consumer.h>
> +#include <linux/iio/consumer.h>
> +#include <linux/interrupt.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/power_supply.h>
> +#include <linux/regmap.h>
> +
> +/* PMIC global control registers definition */
> +#define SC27XX_MODULE_EN0 0xc08
> +#define SC27XX_CLK_EN0 0xc18
> +#define SC27XX_FGU_EN BIT(7)
> +#define SC27XX_FGU_RTC_EN BIT(6)
> +
> +/* FGU registers definition */
> +#define SC27XX_FGU_START 0x0
> +#define SC27XX_FGU_CONFIG 0x4
> +#define SC27XX_FGU_ADC_CONFIG 0x8
> +#define SC27XX_FGU_STATUS 0xc
> +#define SC27XX_FGU_INT_EN 0x10
> +#define SC27XX_FGU_INT_CLR 0x14
> +#define SC27XX_FGU_INT_STS 0x1c
> +#define SC27XX_FGU_VOLTAGE 0x20
> +#define SC27XX_FGU_OCV 0x24
> +#define SC27XX_FGU_POCV 0x28
> +#define SC27XX_FGU_CURRENT 0x2c
> +#define SC27XX_FGU_CLBCNT_SETH 0x50
> +#define SC27XX_FGU_CLBCNT_SETL 0x54
> +#define SC27XX_FGU_CLBCNT_VALH 0x68
> +#define SC27XX_FGU_CLBCNT_VALL 0x6c
> +#define SC27XX_FGU_CLBCNT_QMAXL 0x74
> +
> +#define SC27XX_WRITE_SELCLB_EN BIT(0)
> +#define SC27XX_FGU_CLBCNT_MASK GENMASK(15, 0)
> +#define SC27XX_FGU_CLBCNT_SHIFT 16
> +
> +#define SC27XX_FGU_1000MV_ADC 686
> +#define SC27XX_FGU_1000MA_ADC 1372
> +#define SC27XX_FGU_CUR_BASIC_ADC 8192
> +#define SC27XX_FGU_SAMPLE_HZ 2
> +
> +/*
> + * struct sc27xx_fgu_data: describe the FGU device
> + * @regmap: regmap for register access
> + * @dev: platform device
> + * @battery: battery power supply
> + * @base: the base offset for the controller
> + * @lock: protect the structure
> + * @gpiod: GPIO for battery detection
> + * @channel: IIO channel to get battery temperature
> + * @internal_resist: the battery internal resistance in mOhm
> + * @total_cap: the total capacity of the battery in mAh
> + * @init_cap: the initial capacity of the battery in mAh
> + * @init_clbcnt: the initial coulomb counter
> + * @max_volt: the maximum constant input voltage in millivolt
> + * @table_len: the capacity table length
> + * @cap_table: capacity table with corresponding ocv
> + */
> +struct sc27xx_fgu_data {
> + struct regmap *regmap;
> + struct device *dev;
> + struct power_supply *battery;
> + u32 base;
> + struct mutex lock;
> + struct gpio_desc *gpiod;
> + struct iio_channel *channel;
> + bool bat_present;
> + int internal_resist;
> + int total_cap;
> + int init_cap;
> + int init_clbcnt;
> + int max_volt;
> + int table_len;
> + struct power_supply_battery_ocv_table *cap_table;
> +};
> +
> +static const char * const sc27xx_charger_supply_name[] = {
> + "sc2731_charger",
> + "sc2720_charger",
> + "sc2721_charger",
> + "sc2723_charger",
> +};
> +
> +static int sc27xx_fgu_adc_to_current(int adc)
> +{
> + return (adc * 1000) / SC27XX_FGU_1000MA_ADC;
> +}
> +
> +static int sc27xx_fgu_adc_to_voltage(int adc)
> +{
> + return (adc * 1000) / SC27XX_FGU_1000MV_ADC;
> +}
> +
> +/*
> + * When system boots on, we can not read battery capacity from coulomb
> + * registers, since now the coulomb registers are invalid. So we should
> + * calculate the battery open circuit voltage, and get current battery
> + * capacity according to the capacity table.
> + */
> +static int sc27xx_fgu_get_boot_capacity(struct sc27xx_fgu_data *data, int *cap)
> +{
> + int volt, cur, oci, ocv, ret;
> +
> + /*
> + * After system booting on, the SC27XX_FGU_CLBCNT_QMAXL register saved
> + * the first sampled open circuit current.
> + */
> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_QMAXL,
> + &cur);
> + if (ret)
> + return ret;
> +
> + cur <<= 1;
> + oci = sc27xx_fgu_adc_to_current(cur - SC27XX_FGU_CUR_BASIC_ADC);
> +
> + /*
> + * Should get the OCV from SC27XX_FGU_POCV register at the system
> + * beginning. It is ADC values reading from registers which need to
> + * convert the corresponding voltage.
> + */
> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_POCV, &volt);
> + if (ret)
> + return ret;
> +
> + volt = sc27xx_fgu_adc_to_voltage(volt);
> + ocv = volt - (oci * data->internal_resist) / 1000;
> +
> + /*
> + * Parse the capacity table to look up the correct capacity percent
> + * according to current battery's corresponding OCV values.
> + */
> + *cap = power_supply_ocv2cap_simple(data->cap_table, data->table_len,
> + ocv);
> +
> + return 0;
> +}
> +
> +static int sc27xx_fgu_set_clbcnt(struct sc27xx_fgu_data *data, int clbcnt)
> +{
> + int ret;
> +
> + clbcnt *= SC27XX_FGU_SAMPLE_HZ;
> +
> + ret = regmap_update_bits(data->regmap,
> + data->base + SC27XX_FGU_CLBCNT_SETL,
> + SC27XX_FGU_CLBCNT_MASK, clbcnt);
> + if (ret)
> + return ret;
> +
> + ret = regmap_update_bits(data->regmap,
> + data->base + SC27XX_FGU_CLBCNT_SETH,
> + SC27XX_FGU_CLBCNT_MASK,
> + clbcnt >> SC27XX_FGU_CLBCNT_SHIFT);
> + if (ret)
> + return ret;
> +
> + return regmap_update_bits(data->regmap, data->base + SC27XX_FGU_START,
> + SC27XX_WRITE_SELCLB_EN,
> + SC27XX_WRITE_SELCLB_EN);
> +}
> +
> +static int sc27xx_fgu_get_clbcnt(struct sc27xx_fgu_data *data, int *clb_cnt)
> +{
> + int ccl, cch, ret;
> +
> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALL,
> + &ccl);
> + if (ret)
> + return ret;
> +
> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALH,
> + &cch);
> + if (ret)
> + return ret;
> +
> + *clb_cnt = ccl & SC27XX_FGU_CLBCNT_MASK;
> + *clb_cnt |= (cch & SC27XX_FGU_CLBCNT_MASK) << SC27XX_FGU_CLBCNT_SHIFT;
> + *clb_cnt /= SC27XX_FGU_SAMPLE_HZ;
> +
> + return 0;
> +}
> +
> +static int sc27xx_fgu_get_capacity(struct sc27xx_fgu_data *data, int *cap)
> +{
> + int ret, cur_clbcnt, delta_clbcnt, delta_cap, temp;
> +
> + /* Get current coulomb counters firstly */
> + ret = sc27xx_fgu_get_clbcnt(data, &cur_clbcnt);
> + if (ret)
> + return ret;
> +
> + delta_clbcnt = cur_clbcnt - data->init_clbcnt;
> +
> + /*
> + * Convert coulomb counter to delta capacity (mAh), and set multiplier
> + * as 100 to improve the precision.
> + */
> + temp = DIV_ROUND_CLOSEST(delta_clbcnt, 360);
> + temp = sc27xx_fgu_adc_to_current(temp);
> +
> + /*
> + * Convert to capacity percent of the battery total capacity,
> + * and multiplier is 100 too.
> + */
> + delta_cap = DIV_ROUND_CLOSEST(temp * 100, data->total_cap);
> + *cap = delta_cap + data->init_cap;
> +
> + return 0;
> +}
> +
> +static int sc27xx_fgu_get_vbat_vol(struct sc27xx_fgu_data *data, int *val)
> +{
> + int ret, vol;
> +
> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_VOLTAGE, &vol);
> + if (ret)
> + return ret;
> +
> + /*
> + * It is ADC values reading from registers which need to convert to
> + * corresponding voltage values.
> + */
> + *val = sc27xx_fgu_adc_to_voltage(vol);
> +
> + return 0;
> +}
> +
> +static int sc27xx_fgu_get_current(struct sc27xx_fgu_data *data, int *val)
> +{
> + int ret, cur;
> +
> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CURRENT, &cur);
> + if (ret)
> + return ret;
> +
> + /*
> + * It is ADC values reading from registers which need to convert to
> + * corresponding current values.
> + */
> + *val = sc27xx_fgu_adc_to_current(cur - SC27XX_FGU_CUR_BASIC_ADC);
> +
> + return 0;
> +}
> +
> +static int sc27xx_fgu_get_vbat_ocv(struct sc27xx_fgu_data *data, int *val)
> +{
> + int vol, cur, ret;
> +
> + ret = sc27xx_fgu_get_vbat_vol(data, &vol);
> + if (ret)
> + return ret;
> +
> + ret = sc27xx_fgu_get_current(data, &cur);
> + if (ret)
> + return ret;
> +
> + /* Return the battery OCV in micro volts. */
> + *val = vol * 1000 - cur * data->internal_resist;
> +
> + return 0;
> +}
> +
> +static int sc27xx_fgu_get_temp(struct sc27xx_fgu_data *data, int *temp)
> +{
> + return iio_read_channel_processed(data->channel, temp);
> +}
> +
> +static int sc27xx_fgu_get_health(struct sc27xx_fgu_data *data, int *health)
> +{
> + int ret, vol;
> +
> + ret = sc27xx_fgu_get_vbat_vol(data, &vol);
> + if (ret)
> + return ret;
> +
> + if (vol > data->max_volt)
> + *health = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
> + else
> + *health = POWER_SUPPLY_HEALTH_GOOD;
> +
> + return 0;
> +}
> +
> +static int sc27xx_fgu_get_status(struct sc27xx_fgu_data *data, int *status)
> +{
> + union power_supply_propval val;
> + struct power_supply *psy;
> + int i, ret = -EINVAL;
> +
> + for (i = 0; i < ARRAY_SIZE(sc27xx_charger_supply_name); i++) {
> + psy = power_supply_get_by_name(sc27xx_charger_supply_name[i]);
> + if (!psy)
> + continue;
> +
> + ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_STATUS,
> + &val);
> + power_supply_put(psy);
> + if (ret)
> + return ret;
> +
> + *status = val.intval;
> + }
> +
> + return ret;
> +}
> +
> +static int sc27xx_fgu_get_property(struct power_supply *psy,
> + enum power_supply_property psp,
> + union power_supply_propval *val)
> +{
> + struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
> + int ret = 0;
> + int value;
> +
> + mutex_lock(&data->lock);
> +
> + switch (psp) {
> + case POWER_SUPPLY_PROP_STATUS:
> + ret = sc27xx_fgu_get_status(data, &value);
> + if (ret)
> + goto error;
> +
> + val->intval = value;
> + break;
> +
> + case POWER_SUPPLY_PROP_HEALTH:
> + ret = sc27xx_fgu_get_health(data, &value);
> + if (ret)
> + goto error;
> +
> + val->intval = value;
> + break;
> +
> + case POWER_SUPPLY_PROP_PRESENT:
> + val->intval = data->bat_present;
> + break;
> +
> + case POWER_SUPPLY_PROP_TEMP:
> + ret = sc27xx_fgu_get_temp(data, &value);
> + if (ret)
> + goto error;
> +
> + val->intval = value;
> + break;
> +
> + case POWER_SUPPLY_PROP_TECHNOLOGY:
> + val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
> + break;
> +
> + case POWER_SUPPLY_PROP_CAPACITY:
> + ret = sc27xx_fgu_get_capacity(data, &value);
> + if (ret)
> + goto error;
> +
> + val->intval = value;
> + break;
> +
> + case POWER_SUPPLY_PROP_VOLTAGE_NOW:
> + ret = sc27xx_fgu_get_vbat_vol(data, &value);
> + if (ret)
> + goto error;
> +
> + val->intval = value * 1000;
> + break;
> +
> + case POWER_SUPPLY_PROP_VOLTAGE_OCV:
> + ret = sc27xx_fgu_get_vbat_ocv(data, &value);
> + if (ret)
> + goto error;
> +
> + val->intval = value;
> + break;
> +
> + case POWER_SUPPLY_PROP_CURRENT_NOW:
> + case POWER_SUPPLY_PROP_CURRENT_AVG:
> + ret = sc27xx_fgu_get_current(data, &value);
> + if (ret)
> + goto error;
> +
> + val->intval = value * 1000;
> + break;
> +
> + default:
> + ret = -EINVAL;
> + break;
> + }
> +
> +error:
> + mutex_unlock(&data->lock);
> + return ret;
> +}
> +
> +static void sc27xx_fgu_external_power_changed(struct power_supply *psy)
> +{
> + struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
> +
> + power_supply_changed(data->battery);
> +}
> +
> +static enum power_supply_property sc27xx_fgu_props[] = {
> + POWER_SUPPLY_PROP_STATUS,
> + POWER_SUPPLY_PROP_HEALTH,
> + POWER_SUPPLY_PROP_PRESENT,
> + POWER_SUPPLY_PROP_TEMP,
> + POWER_SUPPLY_PROP_TECHNOLOGY,
> + POWER_SUPPLY_PROP_CAPACITY,
> + POWER_SUPPLY_PROP_VOLTAGE_NOW,
> + POWER_SUPPLY_PROP_VOLTAGE_OCV,
> + POWER_SUPPLY_PROP_CURRENT_NOW,
> + POWER_SUPPLY_PROP_CURRENT_AVG,
> +};
> +
> +static const struct power_supply_desc sc27xx_fgu_desc = {
> + .name = "sc27xx-fgu",
> + .type = POWER_SUPPLY_TYPE_BATTERY,
> + .properties = sc27xx_fgu_props,
> + .num_properties = ARRAY_SIZE(sc27xx_fgu_props),
> + .get_property = sc27xx_fgu_get_property,
> + .external_power_changed = sc27xx_fgu_external_power_changed,
> +};
> +
> +static irqreturn_t sc27xx_fgu_bat_detection(int irq, void *dev_id)
> +{
> + struct sc27xx_fgu_data *data = dev_id;
> + int state;
> +
> + mutex_lock(&data->lock);
> +
> + state = gpiod_get_value_cansleep(data->gpiod);
> + if (state < 0) {
> + dev_err(data->dev, "failed to get gpio state\n");
> + mutex_unlock(&data->lock);
> + return IRQ_RETVAL(state);
> + }
> +
> + data->bat_present = !!state;
> +
> + mutex_unlock(&data->lock);
> +
> + power_supply_changed(data->battery);
> + return IRQ_HANDLED;
> +}
> +
> +static void sc27xx_fgu_disable(void *_data)
> +{
> + struct sc27xx_fgu_data *data = _data;
> +
> + regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
> + regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
> +}
> +
> +static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int capacity)
> +{
> + /*
> + * Get current capacity (mAh) = battery total capacity (mAh) *
> + * current capacity percent (capacity / 100).
> + */
> + int cur_cap = DIV_ROUND_CLOSEST(data->total_cap * capacity, 100);
> +
> + /*
> + * Convert current capacity (mAh) to coulomb counter according to the
> + * formula: 1 mAh =3.6 coulomb.
> + */
> + return DIV_ROUND_CLOSEST(cur_cap * 36, 10);
> +}
> +
> +static int sc27xx_fgu_hw_init(struct sc27xx_fgu_data *data)
> +{
> + struct power_supply_battery_info info = { };
> + struct power_supply_battery_ocv_table *table;
> + int ret, i;
> +
> + ret = power_supply_get_battery_info(data->battery, &info);
> + if (ret) {
> + dev_err(data->dev, "failed to get battery information\n");
> + return ret;
> + }
> +
> + data->total_cap = info.charge_full_design_uah / 1000;
> + data->max_volt = info.constant_charge_voltage_max_uv / 1000;
> + data->internal_resist = info.factory_internal_resistance_uohm / 1000;
> +
> + /*
> + * For SC27XX fuel gauge device, we only use one ocv-capacity
> + * table in normal temperature 20 Celsius.
> + */
> + table = power_supply_find_ocv2cap_table(&info, 20, &data->table_len);
> + if (!table)
> + return -EINVAL;
> +
> + data->cap_table = devm_kzalloc(data->dev,
> + data->table_len * sizeof(*table),
> + GFP_KERNEL);
> + if (!data->cap_table) {
> + power_supply_put_battery_info(data->battery, &info);
> + return -ENOMEM;
> + }
> +
> + for (i = 0; i < data->table_len; i++) {
> + data->cap_table[i].ocv = table[i].ocv / 1000;
> + data->cap_table[i].capacity = table[i].capacity;
> + }

Don't divide the OCV by 1000. You feed this table into the
generic power-supply function later, which should always
get uV. Instead multiply the ocv parameter in your
power_supply_ocv2cap_simple() call with 1000. This
means you can just use devm_kmemdup() here.

Some ideas for later (I'm fine with merging the driver
without these changes):

* Store battery_info directly in private driver data
instead of doing a copy of the temperature table.
* Call power_supply_ocv2cap() with current battery
temperature and let the power-supply core figure
out which ocv-to-capacity curve should be used.

Thanks for your patience :)

-- Sebastian

> + power_supply_put_battery_info(data->battery, &info);
> +
> + /* Enable the FGU module */
> + ret = regmap_update_bits(data->regmap, SC27XX_MODULE_EN0,
> + SC27XX_FGU_EN, SC27XX_FGU_EN);
> + if (ret) {
> + dev_err(data->dev, "failed to enable fgu\n");
> + return ret;
> + }
> +
> + /* Enable the FGU RTC clock to make it work */
> + ret = regmap_update_bits(data->regmap, SC27XX_CLK_EN0,
> + SC27XX_FGU_RTC_EN, SC27XX_FGU_RTC_EN);
> + if (ret) {
> + dev_err(data->dev, "failed to enable fgu RTC clock\n");
> + goto disable_fgu;
> + }
> +
> + /*
> + * Get the boot battery capacity when system powers on, which is used to
> + * initialize the coulomb counter. After that, we can read the coulomb
> + * counter to measure the battery capacity.
> + */
> + ret = sc27xx_fgu_get_boot_capacity(data, &data->init_cap);
> + if (ret) {
> + dev_err(data->dev, "failed to get boot capacity\n");
> + goto disable_clk;
> + }
> +
> + /*
> + * Convert battery capacity to the corresponding initial coulomb counter
> + * and set into coulomb counter registers.
> + */
> + data->init_clbcnt = sc27xx_fgu_cap_to_clbcnt(data, data->init_cap);
> + ret = sc27xx_fgu_set_clbcnt(data, data->init_clbcnt);
> + if (ret) {
> + dev_err(data->dev, "failed to initialize coulomb counter\n");
> + goto disable_clk;
> + }
> +
> + return 0;
> +
> +disable_clk:
> + regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
> +disable_fgu:
> + regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
> +
> + return ret;
> +}


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2018-10-21 19:31:07

by Sebastian Reichel

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Subject: Re: [PATCH v5 5/6] dt-bindings: power: Add Spreadtrum SC27XX fuel gauge unit documentation

Hi,

On Fri, Oct 19, 2018 at 06:53:14PM +0800, Baolin Wang wrote:
> This patch adds the binding documentation for Spreadtrum SC27XX series PMICs
> fuel gauge unit device, which is used to calculate the battery capacity.
>
> Signed-off-by: Baolin Wang <[email protected]>
> Reviewed-by: Linus Walleij <[email protected]>
> Reviewed-by: Rob Herring <[email protected]>
> ---

Looks good to me.

-- Sebastian

> Changes from v4:
> - None.
>
> Changes from v3:
> - Add reviewed tag from Rob.
>
> Changes from v2:
> - Add reviewed tag from Linus.
>
> Changes from v1:
> - Renamed GPIO property.
> - Use standand battery properties instead of 'sprd,inner-resist' and
> 'sprd,ocv-cap-table'.
> - Remove battery node's description.
> ---
> .../devicetree/bindings/power/supply/sc27xx-fg.txt | 52 ++++++++++++++++++++
> 1 file changed, 52 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/power/supply/sc27xx-fg.txt
>
> diff --git a/Documentation/devicetree/bindings/power/supply/sc27xx-fg.txt b/Documentation/devicetree/bindings/power/supply/sc27xx-fg.txt
> new file mode 100644
> index 0000000..98a2400
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/power/supply/sc27xx-fg.txt
> @@ -0,0 +1,52 @@
> +Spreadtrum SC27XX PMICs Fuel Gauge Unit Power Supply Bindings
> +
> +Required properties:
> +- compatible: Should be one of the following:
> + "sprd,sc2720-fgu",
> + "sprd,sc2721-fgu",
> + "sprd,sc2723-fgu",
> + "sprd,sc2730-fgu",
> + "sprd,sc2731-fgu".
> +- reg: The address offset of fuel gauge unit.
> +- battery-detect-gpios: GPIO for battery detection.
> +- io-channels: Specify the IIO ADC channel to get temperature.
> +- io-channel-names: Should be "bat-temp".
> +- monitored-battery: Phandle of battery characteristics devicetree node.
> + See Documentation/devicetree/bindings/power/supply/battery.txt
> +
> +Example:
> +
> + bat: battery {
> + compatible = "simple-battery";
> + charge-full-design-microamp-hours = <1900000>;
> + constant-charge-voltage-max-microvolt = <4350000>;
> + ocv-capacity-celsius = <20>;
> + ocv-capacity-table-0 = <4185000 100>, <4113000 95>, <4066000 90>,
> + <4022000 85>, <3983000 80>, <3949000 75>,
> + <3917000 70>, <3889000 65>, <3864000 60>,
> + <3835000 55>, <3805000 50>, <3787000 45>,
> + <3777000 40>, <3773000 35>, <3770000 30>,
> + <3765000 25>, <3752000 20>, <3724000 15>,
> + <3680000 10>, <3605000 5>, <3400000 0>;
> + ......
> + };
> +
> + sc2731_pmic: pmic@0 {
> + compatible = "sprd,sc2731";
> + reg = <0>;
> + spi-max-frequency = <26000000>;
> + interrupts = <GIC_SPI 31 IRQ_TYPE_LEVEL_HIGH>;
> + interrupt-controller;
> + #interrupt-cells = <2>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + fgu@a00 {
> + compatible = "sprd,sc2731-fgu";
> + reg = <0xa00>;
> + battery-detect-gpios = <&pmic_eic 9 GPIO_ACTIVE_HIGH>;
> + io-channels = <&pmic_adc 5>;
> + io-channel-names = "bat-temp";
> + monitored-battery = <&bat>;
> + };
> + };
> --
> 1.7.9.5
>


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2018-10-22 05:56:38

by Baolin Wang

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Subject: Re: [PATCH v5 6/6] power: supply: Add Spreadtrum SC27XX fuel gauge unit driver

Hi Sebastian,

On 22 October 2018 at 00:52, Sebastian Reichel <[email protected]> wrote:
> Hi,
>
> On Fri, Oct 19, 2018 at 06:53:15PM +0800, Baolin Wang wrote:
>> This patch adds the Spreadtrum SC27XX serial PMICs fuel gauge support,
>> which is used to calculate the battery capacity.
>>
>> Original-by: Yuanjiang Yu <[email protected]>
>> Signed-off-by: Baolin Wang <[email protected]>
>> Acked-by: Linus Walleij <[email protected]>
>> ---
>
> Looks mostly good. I have a few comments still. My plan is to merge
> this early after the merge window, if the final version is finished
> at this point.
>
>> Changes from v4:
>> - None.
>>
>> Changes from v3:
>> - None.
>>
>> Changes from v2:
>> - Use core helper functions to look up OCV capacity table.
>> - Use device_property_read_u32() instead of of_property_read_u32().
>> - Add acked tag from Linus.
>>
>> Changes from v1:
>> - Use battery standard properties to get internal resistance and ocv table.
>> - Change devm_gpiod_get_optional() to devm_gpiod_get().
>> - Add power_supply_changed() when detecting battery present change.
>> - Return micro volts for sc27xx_fgu_get_vbat_ocv().
>> ---
>> drivers/power/supply/Kconfig | 7 +
>> drivers/power/supply/Makefile | 1 +
>> drivers/power/supply/sc27xx_fuel_gauge.c | 661 ++++++++++++++++++++++++++++++
>> 3 files changed, 669 insertions(+)
>> create mode 100644 drivers/power/supply/sc27xx_fuel_gauge.c
>>
>> diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
>> index f27cf07..917f4b7 100644
>> --- a/drivers/power/supply/Kconfig
>> +++ b/drivers/power/supply/Kconfig
>> @@ -652,4 +652,11 @@ config CHARGER_SC2731
>> Say Y here to enable support for battery charging with SC2731
>> PMIC chips.
>>
>> +config FUEL_GAUGE_SC27XX
>> + tristate "Spreadtrum SC27XX fuel gauge driver"
>> + depends on MFD_SC27XX_PMIC || COMPILE_TEST
>> + help
>> + Say Y here to enable support for fuel gauge with SC27XX
>> + PMIC chips.
>> +
>> endif # POWER_SUPPLY
>> diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
>> index 767105b..b731c2a 100644
>> --- a/drivers/power/supply/Makefile
>> +++ b/drivers/power/supply/Makefile
>> @@ -86,3 +86,4 @@ obj-$(CONFIG_AXP288_FUEL_GAUGE) += axp288_fuel_gauge.o
>> obj-$(CONFIG_AXP288_CHARGER) += axp288_charger.o
>> obj-$(CONFIG_CHARGER_CROS_USBPD) += cros_usbpd-charger.o
>> obj-$(CONFIG_CHARGER_SC2731) += sc2731_charger.o
>> +obj-$(CONFIG_FUEL_GAUGE_SC27XX) += sc27xx_fuel_gauge.o
>> diff --git a/drivers/power/supply/sc27xx_fuel_gauge.c b/drivers/power/supply/sc27xx_fuel_gauge.c
>> new file mode 100644
>> index 0000000..1c0b856
>> --- /dev/null
>> +++ b/drivers/power/supply/sc27xx_fuel_gauge.c
>> @@ -0,0 +1,661 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +// Copyright (C) 2018 Spreadtrum Communications Inc.
>> +
>> +#include <linux/gpio/consumer.h>
>> +#include <linux/iio/consumer.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/power_supply.h>
>> +#include <linux/regmap.h>
>> +
>> +/* PMIC global control registers definition */
>> +#define SC27XX_MODULE_EN0 0xc08
>> +#define SC27XX_CLK_EN0 0xc18
>> +#define SC27XX_FGU_EN BIT(7)
>> +#define SC27XX_FGU_RTC_EN BIT(6)
>> +
>> +/* FGU registers definition */
>> +#define SC27XX_FGU_START 0x0
>> +#define SC27XX_FGU_CONFIG 0x4
>> +#define SC27XX_FGU_ADC_CONFIG 0x8
>> +#define SC27XX_FGU_STATUS 0xc
>> +#define SC27XX_FGU_INT_EN 0x10
>> +#define SC27XX_FGU_INT_CLR 0x14
>> +#define SC27XX_FGU_INT_STS 0x1c
>> +#define SC27XX_FGU_VOLTAGE 0x20
>> +#define SC27XX_FGU_OCV 0x24
>> +#define SC27XX_FGU_POCV 0x28
>> +#define SC27XX_FGU_CURRENT 0x2c
>> +#define SC27XX_FGU_CLBCNT_SETH 0x50
>> +#define SC27XX_FGU_CLBCNT_SETL 0x54
>> +#define SC27XX_FGU_CLBCNT_VALH 0x68
>> +#define SC27XX_FGU_CLBCNT_VALL 0x6c
>> +#define SC27XX_FGU_CLBCNT_QMAXL 0x74
>> +
>> +#define SC27XX_WRITE_SELCLB_EN BIT(0)
>> +#define SC27XX_FGU_CLBCNT_MASK GENMASK(15, 0)
>> +#define SC27XX_FGU_CLBCNT_SHIFT 16
>> +
>> +#define SC27XX_FGU_1000MV_ADC 686
>> +#define SC27XX_FGU_1000MA_ADC 1372
>> +#define SC27XX_FGU_CUR_BASIC_ADC 8192
>> +#define SC27XX_FGU_SAMPLE_HZ 2
>> +
>> +/*
>> + * struct sc27xx_fgu_data: describe the FGU device
>> + * @regmap: regmap for register access
>> + * @dev: platform device
>> + * @battery: battery power supply
>> + * @base: the base offset for the controller
>> + * @lock: protect the structure
>> + * @gpiod: GPIO for battery detection
>> + * @channel: IIO channel to get battery temperature
>> + * @internal_resist: the battery internal resistance in mOhm
>> + * @total_cap: the total capacity of the battery in mAh
>> + * @init_cap: the initial capacity of the battery in mAh
>> + * @init_clbcnt: the initial coulomb counter
>> + * @max_volt: the maximum constant input voltage in millivolt
>> + * @table_len: the capacity table length
>> + * @cap_table: capacity table with corresponding ocv
>> + */
>> +struct sc27xx_fgu_data {
>> + struct regmap *regmap;
>> + struct device *dev;
>> + struct power_supply *battery;
>> + u32 base;
>> + struct mutex lock;
>> + struct gpio_desc *gpiod;
>> + struct iio_channel *channel;
>> + bool bat_present;
>> + int internal_resist;
>> + int total_cap;
>> + int init_cap;
>> + int init_clbcnt;
>> + int max_volt;
>> + int table_len;
>> + struct power_supply_battery_ocv_table *cap_table;
>> +};
>> +
>> +static const char * const sc27xx_charger_supply_name[] = {
>> + "sc2731_charger",
>> + "sc2720_charger",
>> + "sc2721_charger",
>> + "sc2723_charger",
>> +};
>> +
>> +static int sc27xx_fgu_adc_to_current(int adc)
>> +{
>> + return (adc * 1000) / SC27XX_FGU_1000MA_ADC;
>> +}
>> +
>> +static int sc27xx_fgu_adc_to_voltage(int adc)
>> +{
>> + return (adc * 1000) / SC27XX_FGU_1000MV_ADC;
>> +}
>> +
>> +/*
>> + * When system boots on, we can not read battery capacity from coulomb
>> + * registers, since now the coulomb registers are invalid. So we should
>> + * calculate the battery open circuit voltage, and get current battery
>> + * capacity according to the capacity table.
>> + */
>> +static int sc27xx_fgu_get_boot_capacity(struct sc27xx_fgu_data *data, int *cap)
>> +{
>> + int volt, cur, oci, ocv, ret;
>> +
>> + /*
>> + * After system booting on, the SC27XX_FGU_CLBCNT_QMAXL register saved
>> + * the first sampled open circuit current.
>> + */
>> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_QMAXL,
>> + &cur);
>> + if (ret)
>> + return ret;
>> +
>> + cur <<= 1;
>> + oci = sc27xx_fgu_adc_to_current(cur - SC27XX_FGU_CUR_BASIC_ADC);
>> +
>> + /*
>> + * Should get the OCV from SC27XX_FGU_POCV register at the system
>> + * beginning. It is ADC values reading from registers which need to
>> + * convert the corresponding voltage.
>> + */
>> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_POCV, &volt);
>> + if (ret)
>> + return ret;
>> +
>> + volt = sc27xx_fgu_adc_to_voltage(volt);
>> + ocv = volt - (oci * data->internal_resist) / 1000;
>> +
>> + /*
>> + * Parse the capacity table to look up the correct capacity percent
>> + * according to current battery's corresponding OCV values.
>> + */
>> + *cap = power_supply_ocv2cap_simple(data->cap_table, data->table_len,
>> + ocv);
>> +
>> + return 0;
>> +}
>> +
>> +static int sc27xx_fgu_set_clbcnt(struct sc27xx_fgu_data *data, int clbcnt)
>> +{
>> + int ret;
>> +
>> + clbcnt *= SC27XX_FGU_SAMPLE_HZ;
>> +
>> + ret = regmap_update_bits(data->regmap,
>> + data->base + SC27XX_FGU_CLBCNT_SETL,
>> + SC27XX_FGU_CLBCNT_MASK, clbcnt);
>> + if (ret)
>> + return ret;
>> +
>> + ret = regmap_update_bits(data->regmap,
>> + data->base + SC27XX_FGU_CLBCNT_SETH,
>> + SC27XX_FGU_CLBCNT_MASK,
>> + clbcnt >> SC27XX_FGU_CLBCNT_SHIFT);
>> + if (ret)
>> + return ret;
>> +
>> + return regmap_update_bits(data->regmap, data->base + SC27XX_FGU_START,
>> + SC27XX_WRITE_SELCLB_EN,
>> + SC27XX_WRITE_SELCLB_EN);
>> +}
>> +
>> +static int sc27xx_fgu_get_clbcnt(struct sc27xx_fgu_data *data, int *clb_cnt)
>> +{
>> + int ccl, cch, ret;
>> +
>> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALL,
>> + &ccl);
>> + if (ret)
>> + return ret;
>> +
>> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALH,
>> + &cch);
>> + if (ret)
>> + return ret;
>> +
>> + *clb_cnt = ccl & SC27XX_FGU_CLBCNT_MASK;
>> + *clb_cnt |= (cch & SC27XX_FGU_CLBCNT_MASK) << SC27XX_FGU_CLBCNT_SHIFT;
>> + *clb_cnt /= SC27XX_FGU_SAMPLE_HZ;
>> +
>> + return 0;
>> +}
>> +
>> +static int sc27xx_fgu_get_capacity(struct sc27xx_fgu_data *data, int *cap)
>> +{
>> + int ret, cur_clbcnt, delta_clbcnt, delta_cap, temp;
>> +
>> + /* Get current coulomb counters firstly */
>> + ret = sc27xx_fgu_get_clbcnt(data, &cur_clbcnt);
>> + if (ret)
>> + return ret;
>> +
>> + delta_clbcnt = cur_clbcnt - data->init_clbcnt;
>> +
>> + /*
>> + * Convert coulomb counter to delta capacity (mAh), and set multiplier
>> + * as 100 to improve the precision.
>> + */
>> + temp = DIV_ROUND_CLOSEST(delta_clbcnt, 360);
>> + temp = sc27xx_fgu_adc_to_current(temp);
>> +
>> + /*
>> + * Convert to capacity percent of the battery total capacity,
>> + * and multiplier is 100 too.
>> + */
>> + delta_cap = DIV_ROUND_CLOSEST(temp * 100, data->total_cap);
>> + *cap = delta_cap + data->init_cap;
>> +
>> + return 0;
>> +}
>> +
>> +static int sc27xx_fgu_get_vbat_vol(struct sc27xx_fgu_data *data, int *val)
>> +{
>> + int ret, vol;
>> +
>> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_VOLTAGE, &vol);
>> + if (ret)
>> + return ret;
>> +
>> + /*
>> + * It is ADC values reading from registers which need to convert to
>> + * corresponding voltage values.
>> + */
>> + *val = sc27xx_fgu_adc_to_voltage(vol);
>> +
>> + return 0;
>> +}
>> +
>> +static int sc27xx_fgu_get_current(struct sc27xx_fgu_data *data, int *val)
>> +{
>> + int ret, cur;
>> +
>> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CURRENT, &cur);
>> + if (ret)
>> + return ret;
>> +
>> + /*
>> + * It is ADC values reading from registers which need to convert to
>> + * corresponding current values.
>> + */
>> + *val = sc27xx_fgu_adc_to_current(cur - SC27XX_FGU_CUR_BASIC_ADC);
>> +
>> + return 0;
>> +}
>> +
>> +static int sc27xx_fgu_get_vbat_ocv(struct sc27xx_fgu_data *data, int *val)
>> +{
>> + int vol, cur, ret;
>> +
>> + ret = sc27xx_fgu_get_vbat_vol(data, &vol);
>> + if (ret)
>> + return ret;
>> +
>> + ret = sc27xx_fgu_get_current(data, &cur);
>> + if (ret)
>> + return ret;
>> +
>> + /* Return the battery OCV in micro volts. */
>> + *val = vol * 1000 - cur * data->internal_resist;
>> +
>> + return 0;
>> +}
>> +
>> +static int sc27xx_fgu_get_temp(struct sc27xx_fgu_data *data, int *temp)
>> +{
>> + return iio_read_channel_processed(data->channel, temp);
>> +}
>> +
>> +static int sc27xx_fgu_get_health(struct sc27xx_fgu_data *data, int *health)
>> +{
>> + int ret, vol;
>> +
>> + ret = sc27xx_fgu_get_vbat_vol(data, &vol);
>> + if (ret)
>> + return ret;
>> +
>> + if (vol > data->max_volt)
>> + *health = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
>> + else
>> + *health = POWER_SUPPLY_HEALTH_GOOD;
>> +
>> + return 0;
>> +}
>> +
>> +static int sc27xx_fgu_get_status(struct sc27xx_fgu_data *data, int *status)
>> +{
>> + union power_supply_propval val;
>> + struct power_supply *psy;
>> + int i, ret = -EINVAL;
>> +
>> + for (i = 0; i < ARRAY_SIZE(sc27xx_charger_supply_name); i++) {
>> + psy = power_supply_get_by_name(sc27xx_charger_supply_name[i]);
>> + if (!psy)
>> + continue;
>> +
>> + ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_STATUS,
>> + &val);
>> + power_supply_put(psy);
>> + if (ret)
>> + return ret;
>> +
>> + *status = val.intval;
>> + }
>> +
>> + return ret;
>> +}
>> +
>> +static int sc27xx_fgu_get_property(struct power_supply *psy,
>> + enum power_supply_property psp,
>> + union power_supply_propval *val)
>> +{
>> + struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
>> + int ret = 0;
>> + int value;
>> +
>> + mutex_lock(&data->lock);
>> +
>> + switch (psp) {
>> + case POWER_SUPPLY_PROP_STATUS:
>> + ret = sc27xx_fgu_get_status(data, &value);
>> + if (ret)
>> + goto error;
>> +
>> + val->intval = value;
>> + break;
>> +
>> + case POWER_SUPPLY_PROP_HEALTH:
>> + ret = sc27xx_fgu_get_health(data, &value);
>> + if (ret)
>> + goto error;
>> +
>> + val->intval = value;
>> + break;
>> +
>> + case POWER_SUPPLY_PROP_PRESENT:
>> + val->intval = data->bat_present;
>> + break;
>> +
>> + case POWER_SUPPLY_PROP_TEMP:
>> + ret = sc27xx_fgu_get_temp(data, &value);
>> + if (ret)
>> + goto error;
>> +
>> + val->intval = value;
>> + break;
>> +
>> + case POWER_SUPPLY_PROP_TECHNOLOGY:
>> + val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
>> + break;
>> +
>> + case POWER_SUPPLY_PROP_CAPACITY:
>> + ret = sc27xx_fgu_get_capacity(data, &value);
>> + if (ret)
>> + goto error;
>> +
>> + val->intval = value;
>> + break;
>> +
>> + case POWER_SUPPLY_PROP_VOLTAGE_NOW:
>> + ret = sc27xx_fgu_get_vbat_vol(data, &value);
>> + if (ret)
>> + goto error;
>> +
>> + val->intval = value * 1000;
>> + break;
>> +
>> + case POWER_SUPPLY_PROP_VOLTAGE_OCV:
>> + ret = sc27xx_fgu_get_vbat_ocv(data, &value);
>> + if (ret)
>> + goto error;
>> +
>> + val->intval = value;
>> + break;
>> +
>> + case POWER_SUPPLY_PROP_CURRENT_NOW:
>> + case POWER_SUPPLY_PROP_CURRENT_AVG:
>> + ret = sc27xx_fgu_get_current(data, &value);
>> + if (ret)
>> + goto error;
>> +
>> + val->intval = value * 1000;
>> + break;
>> +
>> + default:
>> + ret = -EINVAL;
>> + break;
>> + }
>> +
>> +error:
>> + mutex_unlock(&data->lock);
>> + return ret;
>> +}
>> +
>> +static void sc27xx_fgu_external_power_changed(struct power_supply *psy)
>> +{
>> + struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
>> +
>> + power_supply_changed(data->battery);
>> +}
>> +
>> +static enum power_supply_property sc27xx_fgu_props[] = {
>> + POWER_SUPPLY_PROP_STATUS,
>> + POWER_SUPPLY_PROP_HEALTH,
>> + POWER_SUPPLY_PROP_PRESENT,
>> + POWER_SUPPLY_PROP_TEMP,
>> + POWER_SUPPLY_PROP_TECHNOLOGY,
>> + POWER_SUPPLY_PROP_CAPACITY,
>> + POWER_SUPPLY_PROP_VOLTAGE_NOW,
>> + POWER_SUPPLY_PROP_VOLTAGE_OCV,
>> + POWER_SUPPLY_PROP_CURRENT_NOW,
>> + POWER_SUPPLY_PROP_CURRENT_AVG,
>> +};
>> +
>> +static const struct power_supply_desc sc27xx_fgu_desc = {
>> + .name = "sc27xx-fgu",
>> + .type = POWER_SUPPLY_TYPE_BATTERY,
>> + .properties = sc27xx_fgu_props,
>> + .num_properties = ARRAY_SIZE(sc27xx_fgu_props),
>> + .get_property = sc27xx_fgu_get_property,
>> + .external_power_changed = sc27xx_fgu_external_power_changed,
>> +};
>> +
>> +static irqreturn_t sc27xx_fgu_bat_detection(int irq, void *dev_id)
>> +{
>> + struct sc27xx_fgu_data *data = dev_id;
>> + int state;
>> +
>> + mutex_lock(&data->lock);
>> +
>> + state = gpiod_get_value_cansleep(data->gpiod);
>> + if (state < 0) {
>> + dev_err(data->dev, "failed to get gpio state\n");
>> + mutex_unlock(&data->lock);
>> + return IRQ_RETVAL(state);
>> + }
>> +
>> + data->bat_present = !!state;
>> +
>> + mutex_unlock(&data->lock);
>> +
>> + power_supply_changed(data->battery);
>> + return IRQ_HANDLED;
>> +}
>> +
>> +static void sc27xx_fgu_disable(void *_data)
>> +{
>> + struct sc27xx_fgu_data *data = _data;
>> +
>> + regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
>> + regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
>> +}
>> +
>> +static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int capacity)
>> +{
>> + /*
>> + * Get current capacity (mAh) = battery total capacity (mAh) *
>> + * current capacity percent (capacity / 100).
>> + */
>> + int cur_cap = DIV_ROUND_CLOSEST(data->total_cap * capacity, 100);
>> +
>> + /*
>> + * Convert current capacity (mAh) to coulomb counter according to the
>> + * formula: 1 mAh =3.6 coulomb.
>> + */
>> + return DIV_ROUND_CLOSEST(cur_cap * 36, 10);
>> +}
>> +
>> +static int sc27xx_fgu_hw_init(struct sc27xx_fgu_data *data)
>> +{
>> + struct power_supply_battery_info info = { };
>> + struct power_supply_battery_ocv_table *table;
>> + int ret, i;
>> +
>> + ret = power_supply_get_battery_info(data->battery, &info);
>> + if (ret) {
>> + dev_err(data->dev, "failed to get battery information\n");
>> + return ret;
>> + }
>> +
>> + data->total_cap = info.charge_full_design_uah / 1000;
>> + data->max_volt = info.constant_charge_voltage_max_uv / 1000;
>> + data->internal_resist = info.factory_internal_resistance_uohm / 1000;
>> +
>> + /*
>> + * For SC27XX fuel gauge device, we only use one ocv-capacity
>> + * table in normal temperature 20 Celsius.
>> + */
>> + table = power_supply_find_ocv2cap_table(&info, 20, &data->table_len);
>> + if (!table)
>> + return -EINVAL;
>> +
>> + data->cap_table = devm_kzalloc(data->dev,
>> + data->table_len * sizeof(*table),
>> + GFP_KERNEL);
>> + if (!data->cap_table) {
>> + power_supply_put_battery_info(data->battery, &info);
>> + return -ENOMEM;
>> + }
>> +
>> + for (i = 0; i < data->table_len; i++) {
>> + data->cap_table[i].ocv = table[i].ocv / 1000;
>> + data->cap_table[i].capacity = table[i].capacity;
>> + }
>
> Don't divide the OCV by 1000. You feed this table into the
> generic power-supply function later, which should always
> get uV. Instead multiply the ocv parameter in your
> power_supply_ocv2cap_simple() call with 1000. This
> means you can just use devm_kmemdup() here.

Good point. Will change it in next version.

>
> Some ideas for later (I'm fine with merging the driver
> without these changes):
>
> * Store battery_info directly in private driver data
> instead of doing a copy of the temperature table.
> * Call power_supply_ocv2cap() with current battery
> temperature and let the power-supply core figure
> out which ocv-to-capacity curve should be used.

I should keep my original method, since we have no temperature table
now and only use one room temperature (20 degree). Thanks for your
useful comments.

--
Baolin Wang
Best Regards

2018-10-22 10:44:19

by Sebastian Reichel

[permalink] [raw]
Subject: Re: [PATCH v5 6/6] power: supply: Add Spreadtrum SC27XX fuel gauge unit driver

Hi,

On Mon, Oct 22, 2018 at 01:54:50PM +0800, Baolin Wang wrote:
> Hi Sebastian,
>
> On 22 October 2018 at 00:52, Sebastian Reichel <[email protected]> wrote:
> > Hi,
> >
> > On Fri, Oct 19, 2018 at 06:53:15PM +0800, Baolin Wang wrote:
> >> This patch adds the Spreadtrum SC27XX serial PMICs fuel gauge support,
> >> which is used to calculate the battery capacity.
> >>
> >> Original-by: Yuanjiang Yu <[email protected]>
> >> Signed-off-by: Baolin Wang <[email protected]>
> >> Acked-by: Linus Walleij <[email protected]>
> >> ---
> >
> > Looks mostly good. I have a few comments still. My plan is to merge
> > this early after the merge window, if the final version is finished
> > at this point.
> >
> >> Changes from v4:
> >> - None.
> >>
> >> Changes from v3:
> >> - None.
> >>
> >> Changes from v2:
> >> - Use core helper functions to look up OCV capacity table.
> >> - Use device_property_read_u32() instead of of_property_read_u32().
> >> - Add acked tag from Linus.
> >>
> >> Changes from v1:
> >> - Use battery standard properties to get internal resistance and ocv table.
> >> - Change devm_gpiod_get_optional() to devm_gpiod_get().
> >> - Add power_supply_changed() when detecting battery present change.
> >> - Return micro volts for sc27xx_fgu_get_vbat_ocv().
> >> ---
> >> drivers/power/supply/Kconfig | 7 +
> >> drivers/power/supply/Makefile | 1 +
> >> drivers/power/supply/sc27xx_fuel_gauge.c | 661 ++++++++++++++++++++++++++++++
> >> 3 files changed, 669 insertions(+)
> >> create mode 100644 drivers/power/supply/sc27xx_fuel_gauge.c
> >>
> >> diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
> >> index f27cf07..917f4b7 100644
> >> --- a/drivers/power/supply/Kconfig
> >> +++ b/drivers/power/supply/Kconfig
> >> @@ -652,4 +652,11 @@ config CHARGER_SC2731
> >> Say Y here to enable support for battery charging with SC2731
> >> PMIC chips.
> >>
> >> +config FUEL_GAUGE_SC27XX
> >> + tristate "Spreadtrum SC27XX fuel gauge driver"
> >> + depends on MFD_SC27XX_PMIC || COMPILE_TEST
> >> + help
> >> + Say Y here to enable support for fuel gauge with SC27XX
> >> + PMIC chips.
> >> +
> >> endif # POWER_SUPPLY
> >> diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
> >> index 767105b..b731c2a 100644
> >> --- a/drivers/power/supply/Makefile
> >> +++ b/drivers/power/supply/Makefile
> >> @@ -86,3 +86,4 @@ obj-$(CONFIG_AXP288_FUEL_GAUGE) += axp288_fuel_gauge.o
> >> obj-$(CONFIG_AXP288_CHARGER) += axp288_charger.o
> >> obj-$(CONFIG_CHARGER_CROS_USBPD) += cros_usbpd-charger.o
> >> obj-$(CONFIG_CHARGER_SC2731) += sc2731_charger.o
> >> +obj-$(CONFIG_FUEL_GAUGE_SC27XX) += sc27xx_fuel_gauge.o
> >> diff --git a/drivers/power/supply/sc27xx_fuel_gauge.c b/drivers/power/supply/sc27xx_fuel_gauge.c
> >> new file mode 100644
> >> index 0000000..1c0b856
> >> --- /dev/null
> >> +++ b/drivers/power/supply/sc27xx_fuel_gauge.c
> >> @@ -0,0 +1,661 @@
> >> +// SPDX-License-Identifier: GPL-2.0
> >> +// Copyright (C) 2018 Spreadtrum Communications Inc.
> >> +
> >> +#include <linux/gpio/consumer.h>
> >> +#include <linux/iio/consumer.h>
> >> +#include <linux/interrupt.h>
> >> +#include <linux/kernel.h>
> >> +#include <linux/module.h>
> >> +#include <linux/of.h>
> >> +#include <linux/platform_device.h>
> >> +#include <linux/power_supply.h>
> >> +#include <linux/regmap.h>
> >> +
> >> +/* PMIC global control registers definition */
> >> +#define SC27XX_MODULE_EN0 0xc08
> >> +#define SC27XX_CLK_EN0 0xc18
> >> +#define SC27XX_FGU_EN BIT(7)
> >> +#define SC27XX_FGU_RTC_EN BIT(6)
> >> +
> >> +/* FGU registers definition */
> >> +#define SC27XX_FGU_START 0x0
> >> +#define SC27XX_FGU_CONFIG 0x4
> >> +#define SC27XX_FGU_ADC_CONFIG 0x8
> >> +#define SC27XX_FGU_STATUS 0xc
> >> +#define SC27XX_FGU_INT_EN 0x10
> >> +#define SC27XX_FGU_INT_CLR 0x14
> >> +#define SC27XX_FGU_INT_STS 0x1c
> >> +#define SC27XX_FGU_VOLTAGE 0x20
> >> +#define SC27XX_FGU_OCV 0x24
> >> +#define SC27XX_FGU_POCV 0x28
> >> +#define SC27XX_FGU_CURRENT 0x2c
> >> +#define SC27XX_FGU_CLBCNT_SETH 0x50
> >> +#define SC27XX_FGU_CLBCNT_SETL 0x54
> >> +#define SC27XX_FGU_CLBCNT_VALH 0x68
> >> +#define SC27XX_FGU_CLBCNT_VALL 0x6c
> >> +#define SC27XX_FGU_CLBCNT_QMAXL 0x74
> >> +
> >> +#define SC27XX_WRITE_SELCLB_EN BIT(0)
> >> +#define SC27XX_FGU_CLBCNT_MASK GENMASK(15, 0)
> >> +#define SC27XX_FGU_CLBCNT_SHIFT 16
> >> +
> >> +#define SC27XX_FGU_1000MV_ADC 686
> >> +#define SC27XX_FGU_1000MA_ADC 1372
> >> +#define SC27XX_FGU_CUR_BASIC_ADC 8192
> >> +#define SC27XX_FGU_SAMPLE_HZ 2
> >> +
> >> +/*
> >> + * struct sc27xx_fgu_data: describe the FGU device
> >> + * @regmap: regmap for register access
> >> + * @dev: platform device
> >> + * @battery: battery power supply
> >> + * @base: the base offset for the controller
> >> + * @lock: protect the structure
> >> + * @gpiod: GPIO for battery detection
> >> + * @channel: IIO channel to get battery temperature
> >> + * @internal_resist: the battery internal resistance in mOhm
> >> + * @total_cap: the total capacity of the battery in mAh
> >> + * @init_cap: the initial capacity of the battery in mAh
> >> + * @init_clbcnt: the initial coulomb counter
> >> + * @max_volt: the maximum constant input voltage in millivolt
> >> + * @table_len: the capacity table length
> >> + * @cap_table: capacity table with corresponding ocv
> >> + */
> >> +struct sc27xx_fgu_data {
> >> + struct regmap *regmap;
> >> + struct device *dev;
> >> + struct power_supply *battery;
> >> + u32 base;
> >> + struct mutex lock;
> >> + struct gpio_desc *gpiod;
> >> + struct iio_channel *channel;
> >> + bool bat_present;
> >> + int internal_resist;
> >> + int total_cap;
> >> + int init_cap;
> >> + int init_clbcnt;
> >> + int max_volt;
> >> + int table_len;
> >> + struct power_supply_battery_ocv_table *cap_table;
> >> +};
> >> +
> >> +static const char * const sc27xx_charger_supply_name[] = {
> >> + "sc2731_charger",
> >> + "sc2720_charger",
> >> + "sc2721_charger",
> >> + "sc2723_charger",
> >> +};
> >> +
> >> +static int sc27xx_fgu_adc_to_current(int adc)
> >> +{
> >> + return (adc * 1000) / SC27XX_FGU_1000MA_ADC;
> >> +}
> >> +
> >> +static int sc27xx_fgu_adc_to_voltage(int adc)
> >> +{
> >> + return (adc * 1000) / SC27XX_FGU_1000MV_ADC;
> >> +}
> >> +
> >> +/*
> >> + * When system boots on, we can not read battery capacity from coulomb
> >> + * registers, since now the coulomb registers are invalid. So we should
> >> + * calculate the battery open circuit voltage, and get current battery
> >> + * capacity according to the capacity table.
> >> + */
> >> +static int sc27xx_fgu_get_boot_capacity(struct sc27xx_fgu_data *data, int *cap)
> >> +{
> >> + int volt, cur, oci, ocv, ret;
> >> +
> >> + /*
> >> + * After system booting on, the SC27XX_FGU_CLBCNT_QMAXL register saved
> >> + * the first sampled open circuit current.
> >> + */
> >> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_QMAXL,
> >> + &cur);
> >> + if (ret)
> >> + return ret;
> >> +
> >> + cur <<= 1;
> >> + oci = sc27xx_fgu_adc_to_current(cur - SC27XX_FGU_CUR_BASIC_ADC);
> >> +
> >> + /*
> >> + * Should get the OCV from SC27XX_FGU_POCV register at the system
> >> + * beginning. It is ADC values reading from registers which need to
> >> + * convert the corresponding voltage.
> >> + */
> >> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_POCV, &volt);
> >> + if (ret)
> >> + return ret;
> >> +
> >> + volt = sc27xx_fgu_adc_to_voltage(volt);
> >> + ocv = volt - (oci * data->internal_resist) / 1000;
> >> +
> >> + /*
> >> + * Parse the capacity table to look up the correct capacity percent
> >> + * according to current battery's corresponding OCV values.
> >> + */
> >> + *cap = power_supply_ocv2cap_simple(data->cap_table, data->table_len,
> >> + ocv);
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static int sc27xx_fgu_set_clbcnt(struct sc27xx_fgu_data *data, int clbcnt)
> >> +{
> >> + int ret;
> >> +
> >> + clbcnt *= SC27XX_FGU_SAMPLE_HZ;
> >> +
> >> + ret = regmap_update_bits(data->regmap,
> >> + data->base + SC27XX_FGU_CLBCNT_SETL,
> >> + SC27XX_FGU_CLBCNT_MASK, clbcnt);
> >> + if (ret)
> >> + return ret;
> >> +
> >> + ret = regmap_update_bits(data->regmap,
> >> + data->base + SC27XX_FGU_CLBCNT_SETH,
> >> + SC27XX_FGU_CLBCNT_MASK,
> >> + clbcnt >> SC27XX_FGU_CLBCNT_SHIFT);
> >> + if (ret)
> >> + return ret;
> >> +
> >> + return regmap_update_bits(data->regmap, data->base + SC27XX_FGU_START,
> >> + SC27XX_WRITE_SELCLB_EN,
> >> + SC27XX_WRITE_SELCLB_EN);
> >> +}
> >> +
> >> +static int sc27xx_fgu_get_clbcnt(struct sc27xx_fgu_data *data, int *clb_cnt)
> >> +{
> >> + int ccl, cch, ret;
> >> +
> >> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALL,
> >> + &ccl);
> >> + if (ret)
> >> + return ret;
> >> +
> >> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALH,
> >> + &cch);
> >> + if (ret)
> >> + return ret;
> >> +
> >> + *clb_cnt = ccl & SC27XX_FGU_CLBCNT_MASK;
> >> + *clb_cnt |= (cch & SC27XX_FGU_CLBCNT_MASK) << SC27XX_FGU_CLBCNT_SHIFT;
> >> + *clb_cnt /= SC27XX_FGU_SAMPLE_HZ;
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static int sc27xx_fgu_get_capacity(struct sc27xx_fgu_data *data, int *cap)
> >> +{
> >> + int ret, cur_clbcnt, delta_clbcnt, delta_cap, temp;
> >> +
> >> + /* Get current coulomb counters firstly */
> >> + ret = sc27xx_fgu_get_clbcnt(data, &cur_clbcnt);
> >> + if (ret)
> >> + return ret;
> >> +
> >> + delta_clbcnt = cur_clbcnt - data->init_clbcnt;
> >> +
> >> + /*
> >> + * Convert coulomb counter to delta capacity (mAh), and set multiplier
> >> + * as 100 to improve the precision.
> >> + */
> >> + temp = DIV_ROUND_CLOSEST(delta_clbcnt, 360);
> >> + temp = sc27xx_fgu_adc_to_current(temp);
> >> +
> >> + /*
> >> + * Convert to capacity percent of the battery total capacity,
> >> + * and multiplier is 100 too.
> >> + */
> >> + delta_cap = DIV_ROUND_CLOSEST(temp * 100, data->total_cap);
> >> + *cap = delta_cap + data->init_cap;
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static int sc27xx_fgu_get_vbat_vol(struct sc27xx_fgu_data *data, int *val)
> >> +{
> >> + int ret, vol;
> >> +
> >> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_VOLTAGE, &vol);
> >> + if (ret)
> >> + return ret;
> >> +
> >> + /*
> >> + * It is ADC values reading from registers which need to convert to
> >> + * corresponding voltage values.
> >> + */
> >> + *val = sc27xx_fgu_adc_to_voltage(vol);
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static int sc27xx_fgu_get_current(struct sc27xx_fgu_data *data, int *val)
> >> +{
> >> + int ret, cur;
> >> +
> >> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CURRENT, &cur);
> >> + if (ret)
> >> + return ret;
> >> +
> >> + /*
> >> + * It is ADC values reading from registers which need to convert to
> >> + * corresponding current values.
> >> + */
> >> + *val = sc27xx_fgu_adc_to_current(cur - SC27XX_FGU_CUR_BASIC_ADC);
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static int sc27xx_fgu_get_vbat_ocv(struct sc27xx_fgu_data *data, int *val)
> >> +{
> >> + int vol, cur, ret;
> >> +
> >> + ret = sc27xx_fgu_get_vbat_vol(data, &vol);
> >> + if (ret)
> >> + return ret;
> >> +
> >> + ret = sc27xx_fgu_get_current(data, &cur);
> >> + if (ret)
> >> + return ret;
> >> +
> >> + /* Return the battery OCV in micro volts. */
> >> + *val = vol * 1000 - cur * data->internal_resist;
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static int sc27xx_fgu_get_temp(struct sc27xx_fgu_data *data, int *temp)
> >> +{
> >> + return iio_read_channel_processed(data->channel, temp);
> >> +}
> >> +
> >> +static int sc27xx_fgu_get_health(struct sc27xx_fgu_data *data, int *health)
> >> +{
> >> + int ret, vol;
> >> +
> >> + ret = sc27xx_fgu_get_vbat_vol(data, &vol);
> >> + if (ret)
> >> + return ret;
> >> +
> >> + if (vol > data->max_volt)
> >> + *health = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
> >> + else
> >> + *health = POWER_SUPPLY_HEALTH_GOOD;
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static int sc27xx_fgu_get_status(struct sc27xx_fgu_data *data, int *status)
> >> +{
> >> + union power_supply_propval val;
> >> + struct power_supply *psy;
> >> + int i, ret = -EINVAL;
> >> +
> >> + for (i = 0; i < ARRAY_SIZE(sc27xx_charger_supply_name); i++) {
> >> + psy = power_supply_get_by_name(sc27xx_charger_supply_name[i]);
> >> + if (!psy)
> >> + continue;
> >> +
> >> + ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_STATUS,
> >> + &val);
> >> + power_supply_put(psy);
> >> + if (ret)
> >> + return ret;
> >> +
> >> + *status = val.intval;
> >> + }
> >> +
> >> + return ret;
> >> +}
> >> +
> >> +static int sc27xx_fgu_get_property(struct power_supply *psy,
> >> + enum power_supply_property psp,
> >> + union power_supply_propval *val)
> >> +{
> >> + struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
> >> + int ret = 0;
> >> + int value;
> >> +
> >> + mutex_lock(&data->lock);
> >> +
> >> + switch (psp) {
> >> + case POWER_SUPPLY_PROP_STATUS:
> >> + ret = sc27xx_fgu_get_status(data, &value);
> >> + if (ret)
> >> + goto error;
> >> +
> >> + val->intval = value;
> >> + break;
> >> +
> >> + case POWER_SUPPLY_PROP_HEALTH:
> >> + ret = sc27xx_fgu_get_health(data, &value);
> >> + if (ret)
> >> + goto error;
> >> +
> >> + val->intval = value;
> >> + break;
> >> +
> >> + case POWER_SUPPLY_PROP_PRESENT:
> >> + val->intval = data->bat_present;
> >> + break;
> >> +
> >> + case POWER_SUPPLY_PROP_TEMP:
> >> + ret = sc27xx_fgu_get_temp(data, &value);
> >> + if (ret)
> >> + goto error;
> >> +
> >> + val->intval = value;
> >> + break;
> >> +
> >> + case POWER_SUPPLY_PROP_TECHNOLOGY:
> >> + val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
> >> + break;
> >> +
> >> + case POWER_SUPPLY_PROP_CAPACITY:
> >> + ret = sc27xx_fgu_get_capacity(data, &value);
> >> + if (ret)
> >> + goto error;
> >> +
> >> + val->intval = value;
> >> + break;
> >> +
> >> + case POWER_SUPPLY_PROP_VOLTAGE_NOW:
> >> + ret = sc27xx_fgu_get_vbat_vol(data, &value);
> >> + if (ret)
> >> + goto error;
> >> +
> >> + val->intval = value * 1000;
> >> + break;
> >> +
> >> + case POWER_SUPPLY_PROP_VOLTAGE_OCV:
> >> + ret = sc27xx_fgu_get_vbat_ocv(data, &value);
> >> + if (ret)
> >> + goto error;
> >> +
> >> + val->intval = value;
> >> + break;
> >> +
> >> + case POWER_SUPPLY_PROP_CURRENT_NOW:
> >> + case POWER_SUPPLY_PROP_CURRENT_AVG:
> >> + ret = sc27xx_fgu_get_current(data, &value);
> >> + if (ret)
> >> + goto error;
> >> +
> >> + val->intval = value * 1000;
> >> + break;
> >> +
> >> + default:
> >> + ret = -EINVAL;
> >> + break;
> >> + }
> >> +
> >> +error:
> >> + mutex_unlock(&data->lock);
> >> + return ret;
> >> +}
> >> +
> >> +static void sc27xx_fgu_external_power_changed(struct power_supply *psy)
> >> +{
> >> + struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
> >> +
> >> + power_supply_changed(data->battery);
> >> +}
> >> +
> >> +static enum power_supply_property sc27xx_fgu_props[] = {
> >> + POWER_SUPPLY_PROP_STATUS,
> >> + POWER_SUPPLY_PROP_HEALTH,
> >> + POWER_SUPPLY_PROP_PRESENT,
> >> + POWER_SUPPLY_PROP_TEMP,
> >> + POWER_SUPPLY_PROP_TECHNOLOGY,
> >> + POWER_SUPPLY_PROP_CAPACITY,
> >> + POWER_SUPPLY_PROP_VOLTAGE_NOW,
> >> + POWER_SUPPLY_PROP_VOLTAGE_OCV,
> >> + POWER_SUPPLY_PROP_CURRENT_NOW,
> >> + POWER_SUPPLY_PROP_CURRENT_AVG,
> >> +};
> >> +
> >> +static const struct power_supply_desc sc27xx_fgu_desc = {
> >> + .name = "sc27xx-fgu",
> >> + .type = POWER_SUPPLY_TYPE_BATTERY,
> >> + .properties = sc27xx_fgu_props,
> >> + .num_properties = ARRAY_SIZE(sc27xx_fgu_props),
> >> + .get_property = sc27xx_fgu_get_property,
> >> + .external_power_changed = sc27xx_fgu_external_power_changed,
> >> +};
> >> +
> >> +static irqreturn_t sc27xx_fgu_bat_detection(int irq, void *dev_id)
> >> +{
> >> + struct sc27xx_fgu_data *data = dev_id;
> >> + int state;
> >> +
> >> + mutex_lock(&data->lock);
> >> +
> >> + state = gpiod_get_value_cansleep(data->gpiod);
> >> + if (state < 0) {
> >> + dev_err(data->dev, "failed to get gpio state\n");
> >> + mutex_unlock(&data->lock);
> >> + return IRQ_RETVAL(state);
> >> + }
> >> +
> >> + data->bat_present = !!state;
> >> +
> >> + mutex_unlock(&data->lock);
> >> +
> >> + power_supply_changed(data->battery);
> >> + return IRQ_HANDLED;
> >> +}
> >> +
> >> +static void sc27xx_fgu_disable(void *_data)
> >> +{
> >> + struct sc27xx_fgu_data *data = _data;
> >> +
> >> + regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
> >> + regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
> >> +}
> >> +
> >> +static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int capacity)
> >> +{
> >> + /*
> >> + * Get current capacity (mAh) = battery total capacity (mAh) *
> >> + * current capacity percent (capacity / 100).
> >> + */
> >> + int cur_cap = DIV_ROUND_CLOSEST(data->total_cap * capacity, 100);
> >> +
> >> + /*
> >> + * Convert current capacity (mAh) to coulomb counter according to the
> >> + * formula: 1 mAh =3.6 coulomb.
> >> + */
> >> + return DIV_ROUND_CLOSEST(cur_cap * 36, 10);
> >> +}
> >> +
> >> +static int sc27xx_fgu_hw_init(struct sc27xx_fgu_data *data)
> >> +{
> >> + struct power_supply_battery_info info = { };
> >> + struct power_supply_battery_ocv_table *table;
> >> + int ret, i;
> >> +
> >> + ret = power_supply_get_battery_info(data->battery, &info);
> >> + if (ret) {
> >> + dev_err(data->dev, "failed to get battery information\n");
> >> + return ret;
> >> + }
> >> +
> >> + data->total_cap = info.charge_full_design_uah / 1000;
> >> + data->max_volt = info.constant_charge_voltage_max_uv / 1000;
> >> + data->internal_resist = info.factory_internal_resistance_uohm / 1000;
> >> +
> >> + /*
> >> + * For SC27XX fuel gauge device, we only use one ocv-capacity
> >> + * table in normal temperature 20 Celsius.
> >> + */
> >> + table = power_supply_find_ocv2cap_table(&info, 20, &data->table_len);
> >> + if (!table)
> >> + return -EINVAL;
> >> +
> >> + data->cap_table = devm_kzalloc(data->dev,
> >> + data->table_len * sizeof(*table),
> >> + GFP_KERNEL);
> >> + if (!data->cap_table) {
> >> + power_supply_put_battery_info(data->battery, &info);
> >> + return -ENOMEM;
> >> + }
> >> +
> >> + for (i = 0; i < data->table_len; i++) {
> >> + data->cap_table[i].ocv = table[i].ocv / 1000;
> >> + data->cap_table[i].capacity = table[i].capacity;
> >> + }
> >
> > Don't divide the OCV by 1000. You feed this table into the
> > generic power-supply function later, which should always
> > get uV. Instead multiply the ocv parameter in your
> > power_supply_ocv2cap_simple() call with 1000. This
> > means you can just use devm_kmemdup() here.
>
> Good point. Will change it in next version.
>
> >
> > Some ideas for later (I'm fine with merging the driver
> > without these changes):
> >
> > * Store battery_info directly in private driver data
> > instead of doing a copy of the temperature table.
> > * Call power_supply_ocv2cap() with current battery
> > temperature and let the power-supply core figure
> > out which ocv-to-capacity curve should be used.
>
> I should keep my original method, since we have no temperature table
> now and only use one room temperature (20 degree). Thanks for your
> useful comments.

Which should work perfectly fine with power_supply_ocv2cap(). It
will use the nearest curve, which is always the 20?C one in your
case. If you add a second temperature curve in the future (i.e.
because of using the sc27xx fuel gauge with a different battery),
it would just pick this up automatically. But I'm fine with doing
this later.

-- Sebastian


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2018-10-22 10:51:17

by Baolin Wang

[permalink] [raw]
Subject: Re: [PATCH v5 6/6] power: supply: Add Spreadtrum SC27XX fuel gauge unit driver

On 22 October 2018 at 18:43, Sebastian Reichel <[email protected]> wrote:
> Hi,
>
> On Mon, Oct 22, 2018 at 01:54:50PM +0800, Baolin Wang wrote:
>> Hi Sebastian,
>>
>> On 22 October 2018 at 00:52, Sebastian Reichel <[email protected]> wrote:
>> > Hi,
>> >
>> > On Fri, Oct 19, 2018 at 06:53:15PM +0800, Baolin Wang wrote:
>> >> This patch adds the Spreadtrum SC27XX serial PMICs fuel gauge support,
>> >> which is used to calculate the battery capacity.
>> >>
>> >> Original-by: Yuanjiang Yu <[email protected]>
>> >> Signed-off-by: Baolin Wang <[email protected]>
>> >> Acked-by: Linus Walleij <[email protected]>
>> >> ---
>> >
>> > Looks mostly good. I have a few comments still. My plan is to merge
>> > this early after the merge window, if the final version is finished
>> > at this point.
>> >
>> >> Changes from v4:
>> >> - None.
>> >>
>> >> Changes from v3:
>> >> - None.
>> >>
>> >> Changes from v2:
>> >> - Use core helper functions to look up OCV capacity table.
>> >> - Use device_property_read_u32() instead of of_property_read_u32().
>> >> - Add acked tag from Linus.
>> >>
>> >> Changes from v1:
>> >> - Use battery standard properties to get internal resistance and ocv table.
>> >> - Change devm_gpiod_get_optional() to devm_gpiod_get().
>> >> - Add power_supply_changed() when detecting battery present change.
>> >> - Return micro volts for sc27xx_fgu_get_vbat_ocv().
>> >> ---
>> >> drivers/power/supply/Kconfig | 7 +
>> >> drivers/power/supply/Makefile | 1 +
>> >> drivers/power/supply/sc27xx_fuel_gauge.c | 661 ++++++++++++++++++++++++++++++
>> >> 3 files changed, 669 insertions(+)
>> >> create mode 100644 drivers/power/supply/sc27xx_fuel_gauge.c
>> >>
>> >> diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
>> >> index f27cf07..917f4b7 100644
>> >> --- a/drivers/power/supply/Kconfig
>> >> +++ b/drivers/power/supply/Kconfig
>> >> @@ -652,4 +652,11 @@ config CHARGER_SC2731
>> >> Say Y here to enable support for battery charging with SC2731
>> >> PMIC chips.
>> >>
>> >> +config FUEL_GAUGE_SC27XX
>> >> + tristate "Spreadtrum SC27XX fuel gauge driver"
>> >> + depends on MFD_SC27XX_PMIC || COMPILE_TEST
>> >> + help
>> >> + Say Y here to enable support for fuel gauge with SC27XX
>> >> + PMIC chips.
>> >> +
>> >> endif # POWER_SUPPLY
>> >> diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
>> >> index 767105b..b731c2a 100644
>> >> --- a/drivers/power/supply/Makefile
>> >> +++ b/drivers/power/supply/Makefile
>> >> @@ -86,3 +86,4 @@ obj-$(CONFIG_AXP288_FUEL_GAUGE) += axp288_fuel_gauge.o
>> >> obj-$(CONFIG_AXP288_CHARGER) += axp288_charger.o
>> >> obj-$(CONFIG_CHARGER_CROS_USBPD) += cros_usbpd-charger.o
>> >> obj-$(CONFIG_CHARGER_SC2731) += sc2731_charger.o
>> >> +obj-$(CONFIG_FUEL_GAUGE_SC27XX) += sc27xx_fuel_gauge.o
>> >> diff --git a/drivers/power/supply/sc27xx_fuel_gauge.c b/drivers/power/supply/sc27xx_fuel_gauge.c
>> >> new file mode 100644
>> >> index 0000000..1c0b856
>> >> --- /dev/null
>> >> +++ b/drivers/power/supply/sc27xx_fuel_gauge.c
>> >> @@ -0,0 +1,661 @@
>> >> +// SPDX-License-Identifier: GPL-2.0
>> >> +// Copyright (C) 2018 Spreadtrum Communications Inc.
>> >> +
>> >> +#include <linux/gpio/consumer.h>
>> >> +#include <linux/iio/consumer.h>
>> >> +#include <linux/interrupt.h>
>> >> +#include <linux/kernel.h>
>> >> +#include <linux/module.h>
>> >> +#include <linux/of.h>
>> >> +#include <linux/platform_device.h>
>> >> +#include <linux/power_supply.h>
>> >> +#include <linux/regmap.h>
>> >> +
>> >> +/* PMIC global control registers definition */
>> >> +#define SC27XX_MODULE_EN0 0xc08
>> >> +#define SC27XX_CLK_EN0 0xc18
>> >> +#define SC27XX_FGU_EN BIT(7)
>> >> +#define SC27XX_FGU_RTC_EN BIT(6)
>> >> +
>> >> +/* FGU registers definition */
>> >> +#define SC27XX_FGU_START 0x0
>> >> +#define SC27XX_FGU_CONFIG 0x4
>> >> +#define SC27XX_FGU_ADC_CONFIG 0x8
>> >> +#define SC27XX_FGU_STATUS 0xc
>> >> +#define SC27XX_FGU_INT_EN 0x10
>> >> +#define SC27XX_FGU_INT_CLR 0x14
>> >> +#define SC27XX_FGU_INT_STS 0x1c
>> >> +#define SC27XX_FGU_VOLTAGE 0x20
>> >> +#define SC27XX_FGU_OCV 0x24
>> >> +#define SC27XX_FGU_POCV 0x28
>> >> +#define SC27XX_FGU_CURRENT 0x2c
>> >> +#define SC27XX_FGU_CLBCNT_SETH 0x50
>> >> +#define SC27XX_FGU_CLBCNT_SETL 0x54
>> >> +#define SC27XX_FGU_CLBCNT_VALH 0x68
>> >> +#define SC27XX_FGU_CLBCNT_VALL 0x6c
>> >> +#define SC27XX_FGU_CLBCNT_QMAXL 0x74
>> >> +
>> >> +#define SC27XX_WRITE_SELCLB_EN BIT(0)
>> >> +#define SC27XX_FGU_CLBCNT_MASK GENMASK(15, 0)
>> >> +#define SC27XX_FGU_CLBCNT_SHIFT 16
>> >> +
>> >> +#define SC27XX_FGU_1000MV_ADC 686
>> >> +#define SC27XX_FGU_1000MA_ADC 1372
>> >> +#define SC27XX_FGU_CUR_BASIC_ADC 8192
>> >> +#define SC27XX_FGU_SAMPLE_HZ 2
>> >> +
>> >> +/*
>> >> + * struct sc27xx_fgu_data: describe the FGU device
>> >> + * @regmap: regmap for register access
>> >> + * @dev: platform device
>> >> + * @battery: battery power supply
>> >> + * @base: the base offset for the controller
>> >> + * @lock: protect the structure
>> >> + * @gpiod: GPIO for battery detection
>> >> + * @channel: IIO channel to get battery temperature
>> >> + * @internal_resist: the battery internal resistance in mOhm
>> >> + * @total_cap: the total capacity of the battery in mAh
>> >> + * @init_cap: the initial capacity of the battery in mAh
>> >> + * @init_clbcnt: the initial coulomb counter
>> >> + * @max_volt: the maximum constant input voltage in millivolt
>> >> + * @table_len: the capacity table length
>> >> + * @cap_table: capacity table with corresponding ocv
>> >> + */
>> >> +struct sc27xx_fgu_data {
>> >> + struct regmap *regmap;
>> >> + struct device *dev;
>> >> + struct power_supply *battery;
>> >> + u32 base;
>> >> + struct mutex lock;
>> >> + struct gpio_desc *gpiod;
>> >> + struct iio_channel *channel;
>> >> + bool bat_present;
>> >> + int internal_resist;
>> >> + int total_cap;
>> >> + int init_cap;
>> >> + int init_clbcnt;
>> >> + int max_volt;
>> >> + int table_len;
>> >> + struct power_supply_battery_ocv_table *cap_table;
>> >> +};
>> >> +
>> >> +static const char * const sc27xx_charger_supply_name[] = {
>> >> + "sc2731_charger",
>> >> + "sc2720_charger",
>> >> + "sc2721_charger",
>> >> + "sc2723_charger",
>> >> +};
>> >> +
>> >> +static int sc27xx_fgu_adc_to_current(int adc)
>> >> +{
>> >> + return (adc * 1000) / SC27XX_FGU_1000MA_ADC;
>> >> +}
>> >> +
>> >> +static int sc27xx_fgu_adc_to_voltage(int adc)
>> >> +{
>> >> + return (adc * 1000) / SC27XX_FGU_1000MV_ADC;
>> >> +}
>> >> +
>> >> +/*
>> >> + * When system boots on, we can not read battery capacity from coulomb
>> >> + * registers, since now the coulomb registers are invalid. So we should
>> >> + * calculate the battery open circuit voltage, and get current battery
>> >> + * capacity according to the capacity table.
>> >> + */
>> >> +static int sc27xx_fgu_get_boot_capacity(struct sc27xx_fgu_data *data, int *cap)
>> >> +{
>> >> + int volt, cur, oci, ocv, ret;
>> >> +
>> >> + /*
>> >> + * After system booting on, the SC27XX_FGU_CLBCNT_QMAXL register saved
>> >> + * the first sampled open circuit current.
>> >> + */
>> >> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_QMAXL,
>> >> + &cur);
>> >> + if (ret)
>> >> + return ret;
>> >> +
>> >> + cur <<= 1;
>> >> + oci = sc27xx_fgu_adc_to_current(cur - SC27XX_FGU_CUR_BASIC_ADC);
>> >> +
>> >> + /*
>> >> + * Should get the OCV from SC27XX_FGU_POCV register at the system
>> >> + * beginning. It is ADC values reading from registers which need to
>> >> + * convert the corresponding voltage.
>> >> + */
>> >> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_POCV, &volt);
>> >> + if (ret)
>> >> + return ret;
>> >> +
>> >> + volt = sc27xx_fgu_adc_to_voltage(volt);
>> >> + ocv = volt - (oci * data->internal_resist) / 1000;
>> >> +
>> >> + /*
>> >> + * Parse the capacity table to look up the correct capacity percent
>> >> + * according to current battery's corresponding OCV values.
>> >> + */
>> >> + *cap = power_supply_ocv2cap_simple(data->cap_table, data->table_len,
>> >> + ocv);
>> >> +
>> >> + return 0;
>> >> +}
>> >> +
>> >> +static int sc27xx_fgu_set_clbcnt(struct sc27xx_fgu_data *data, int clbcnt)
>> >> +{
>> >> + int ret;
>> >> +
>> >> + clbcnt *= SC27XX_FGU_SAMPLE_HZ;
>> >> +
>> >> + ret = regmap_update_bits(data->regmap,
>> >> + data->base + SC27XX_FGU_CLBCNT_SETL,
>> >> + SC27XX_FGU_CLBCNT_MASK, clbcnt);
>> >> + if (ret)
>> >> + return ret;
>> >> +
>> >> + ret = regmap_update_bits(data->regmap,
>> >> + data->base + SC27XX_FGU_CLBCNT_SETH,
>> >> + SC27XX_FGU_CLBCNT_MASK,
>> >> + clbcnt >> SC27XX_FGU_CLBCNT_SHIFT);
>> >> + if (ret)
>> >> + return ret;
>> >> +
>> >> + return regmap_update_bits(data->regmap, data->base + SC27XX_FGU_START,
>> >> + SC27XX_WRITE_SELCLB_EN,
>> >> + SC27XX_WRITE_SELCLB_EN);
>> >> +}
>> >> +
>> >> +static int sc27xx_fgu_get_clbcnt(struct sc27xx_fgu_data *data, int *clb_cnt)
>> >> +{
>> >> + int ccl, cch, ret;
>> >> +
>> >> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALL,
>> >> + &ccl);
>> >> + if (ret)
>> >> + return ret;
>> >> +
>> >> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALH,
>> >> + &cch);
>> >> + if (ret)
>> >> + return ret;
>> >> +
>> >> + *clb_cnt = ccl & SC27XX_FGU_CLBCNT_MASK;
>> >> + *clb_cnt |= (cch & SC27XX_FGU_CLBCNT_MASK) << SC27XX_FGU_CLBCNT_SHIFT;
>> >> + *clb_cnt /= SC27XX_FGU_SAMPLE_HZ;
>> >> +
>> >> + return 0;
>> >> +}
>> >> +
>> >> +static int sc27xx_fgu_get_capacity(struct sc27xx_fgu_data *data, int *cap)
>> >> +{
>> >> + int ret, cur_clbcnt, delta_clbcnt, delta_cap, temp;
>> >> +
>> >> + /* Get current coulomb counters firstly */
>> >> + ret = sc27xx_fgu_get_clbcnt(data, &cur_clbcnt);
>> >> + if (ret)
>> >> + return ret;
>> >> +
>> >> + delta_clbcnt = cur_clbcnt - data->init_clbcnt;
>> >> +
>> >> + /*
>> >> + * Convert coulomb counter to delta capacity (mAh), and set multiplier
>> >> + * as 100 to improve the precision.
>> >> + */
>> >> + temp = DIV_ROUND_CLOSEST(delta_clbcnt, 360);
>> >> + temp = sc27xx_fgu_adc_to_current(temp);
>> >> +
>> >> + /*
>> >> + * Convert to capacity percent of the battery total capacity,
>> >> + * and multiplier is 100 too.
>> >> + */
>> >> + delta_cap = DIV_ROUND_CLOSEST(temp * 100, data->total_cap);
>> >> + *cap = delta_cap + data->init_cap;
>> >> +
>> >> + return 0;
>> >> +}
>> >> +
>> >> +static int sc27xx_fgu_get_vbat_vol(struct sc27xx_fgu_data *data, int *val)
>> >> +{
>> >> + int ret, vol;
>> >> +
>> >> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_VOLTAGE, &vol);
>> >> + if (ret)
>> >> + return ret;
>> >> +
>> >> + /*
>> >> + * It is ADC values reading from registers which need to convert to
>> >> + * corresponding voltage values.
>> >> + */
>> >> + *val = sc27xx_fgu_adc_to_voltage(vol);
>> >> +
>> >> + return 0;
>> >> +}
>> >> +
>> >> +static int sc27xx_fgu_get_current(struct sc27xx_fgu_data *data, int *val)
>> >> +{
>> >> + int ret, cur;
>> >> +
>> >> + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CURRENT, &cur);
>> >> + if (ret)
>> >> + return ret;
>> >> +
>> >> + /*
>> >> + * It is ADC values reading from registers which need to convert to
>> >> + * corresponding current values.
>> >> + */
>> >> + *val = sc27xx_fgu_adc_to_current(cur - SC27XX_FGU_CUR_BASIC_ADC);
>> >> +
>> >> + return 0;
>> >> +}
>> >> +
>> >> +static int sc27xx_fgu_get_vbat_ocv(struct sc27xx_fgu_data *data, int *val)
>> >> +{
>> >> + int vol, cur, ret;
>> >> +
>> >> + ret = sc27xx_fgu_get_vbat_vol(data, &vol);
>> >> + if (ret)
>> >> + return ret;
>> >> +
>> >> + ret = sc27xx_fgu_get_current(data, &cur);
>> >> + if (ret)
>> >> + return ret;
>> >> +
>> >> + /* Return the battery OCV in micro volts. */
>> >> + *val = vol * 1000 - cur * data->internal_resist;
>> >> +
>> >> + return 0;
>> >> +}
>> >> +
>> >> +static int sc27xx_fgu_get_temp(struct sc27xx_fgu_data *data, int *temp)
>> >> +{
>> >> + return iio_read_channel_processed(data->channel, temp);
>> >> +}
>> >> +
>> >> +static int sc27xx_fgu_get_health(struct sc27xx_fgu_data *data, int *health)
>> >> +{
>> >> + int ret, vol;
>> >> +
>> >> + ret = sc27xx_fgu_get_vbat_vol(data, &vol);
>> >> + if (ret)
>> >> + return ret;
>> >> +
>> >> + if (vol > data->max_volt)
>> >> + *health = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
>> >> + else
>> >> + *health = POWER_SUPPLY_HEALTH_GOOD;
>> >> +
>> >> + return 0;
>> >> +}
>> >> +
>> >> +static int sc27xx_fgu_get_status(struct sc27xx_fgu_data *data, int *status)
>> >> +{
>> >> + union power_supply_propval val;
>> >> + struct power_supply *psy;
>> >> + int i, ret = -EINVAL;
>> >> +
>> >> + for (i = 0; i < ARRAY_SIZE(sc27xx_charger_supply_name); i++) {
>> >> + psy = power_supply_get_by_name(sc27xx_charger_supply_name[i]);
>> >> + if (!psy)
>> >> + continue;
>> >> +
>> >> + ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_STATUS,
>> >> + &val);
>> >> + power_supply_put(psy);
>> >> + if (ret)
>> >> + return ret;
>> >> +
>> >> + *status = val.intval;
>> >> + }
>> >> +
>> >> + return ret;
>> >> +}
>> >> +
>> >> +static int sc27xx_fgu_get_property(struct power_supply *psy,
>> >> + enum power_supply_property psp,
>> >> + union power_supply_propval *val)
>> >> +{
>> >> + struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
>> >> + int ret = 0;
>> >> + int value;
>> >> +
>> >> + mutex_lock(&data->lock);
>> >> +
>> >> + switch (psp) {
>> >> + case POWER_SUPPLY_PROP_STATUS:
>> >> + ret = sc27xx_fgu_get_status(data, &value);
>> >> + if (ret)
>> >> + goto error;
>> >> +
>> >> + val->intval = value;
>> >> + break;
>> >> +
>> >> + case POWER_SUPPLY_PROP_HEALTH:
>> >> + ret = sc27xx_fgu_get_health(data, &value);
>> >> + if (ret)
>> >> + goto error;
>> >> +
>> >> + val->intval = value;
>> >> + break;
>> >> +
>> >> + case POWER_SUPPLY_PROP_PRESENT:
>> >> + val->intval = data->bat_present;
>> >> + break;
>> >> +
>> >> + case POWER_SUPPLY_PROP_TEMP:
>> >> + ret = sc27xx_fgu_get_temp(data, &value);
>> >> + if (ret)
>> >> + goto error;
>> >> +
>> >> + val->intval = value;
>> >> + break;
>> >> +
>> >> + case POWER_SUPPLY_PROP_TECHNOLOGY:
>> >> + val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
>> >> + break;
>> >> +
>> >> + case POWER_SUPPLY_PROP_CAPACITY:
>> >> + ret = sc27xx_fgu_get_capacity(data, &value);
>> >> + if (ret)
>> >> + goto error;
>> >> +
>> >> + val->intval = value;
>> >> + break;
>> >> +
>> >> + case POWER_SUPPLY_PROP_VOLTAGE_NOW:
>> >> + ret = sc27xx_fgu_get_vbat_vol(data, &value);
>> >> + if (ret)
>> >> + goto error;
>> >> +
>> >> + val->intval = value * 1000;
>> >> + break;
>> >> +
>> >> + case POWER_SUPPLY_PROP_VOLTAGE_OCV:
>> >> + ret = sc27xx_fgu_get_vbat_ocv(data, &value);
>> >> + if (ret)
>> >> + goto error;
>> >> +
>> >> + val->intval = value;
>> >> + break;
>> >> +
>> >> + case POWER_SUPPLY_PROP_CURRENT_NOW:
>> >> + case POWER_SUPPLY_PROP_CURRENT_AVG:
>> >> + ret = sc27xx_fgu_get_current(data, &value);
>> >> + if (ret)
>> >> + goto error;
>> >> +
>> >> + val->intval = value * 1000;
>> >> + break;
>> >> +
>> >> + default:
>> >> + ret = -EINVAL;
>> >> + break;
>> >> + }
>> >> +
>> >> +error:
>> >> + mutex_unlock(&data->lock);
>> >> + return ret;
>> >> +}
>> >> +
>> >> +static void sc27xx_fgu_external_power_changed(struct power_supply *psy)
>> >> +{
>> >> + struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
>> >> +
>> >> + power_supply_changed(data->battery);
>> >> +}
>> >> +
>> >> +static enum power_supply_property sc27xx_fgu_props[] = {
>> >> + POWER_SUPPLY_PROP_STATUS,
>> >> + POWER_SUPPLY_PROP_HEALTH,
>> >> + POWER_SUPPLY_PROP_PRESENT,
>> >> + POWER_SUPPLY_PROP_TEMP,
>> >> + POWER_SUPPLY_PROP_TECHNOLOGY,
>> >> + POWER_SUPPLY_PROP_CAPACITY,
>> >> + POWER_SUPPLY_PROP_VOLTAGE_NOW,
>> >> + POWER_SUPPLY_PROP_VOLTAGE_OCV,
>> >> + POWER_SUPPLY_PROP_CURRENT_NOW,
>> >> + POWER_SUPPLY_PROP_CURRENT_AVG,
>> >> +};
>> >> +
>> >> +static const struct power_supply_desc sc27xx_fgu_desc = {
>> >> + .name = "sc27xx-fgu",
>> >> + .type = POWER_SUPPLY_TYPE_BATTERY,
>> >> + .properties = sc27xx_fgu_props,
>> >> + .num_properties = ARRAY_SIZE(sc27xx_fgu_props),
>> >> + .get_property = sc27xx_fgu_get_property,
>> >> + .external_power_changed = sc27xx_fgu_external_power_changed,
>> >> +};
>> >> +
>> >> +static irqreturn_t sc27xx_fgu_bat_detection(int irq, void *dev_id)
>> >> +{
>> >> + struct sc27xx_fgu_data *data = dev_id;
>> >> + int state;
>> >> +
>> >> + mutex_lock(&data->lock);
>> >> +
>> >> + state = gpiod_get_value_cansleep(data->gpiod);
>> >> + if (state < 0) {
>> >> + dev_err(data->dev, "failed to get gpio state\n");
>> >> + mutex_unlock(&data->lock);
>> >> + return IRQ_RETVAL(state);
>> >> + }
>> >> +
>> >> + data->bat_present = !!state;
>> >> +
>> >> + mutex_unlock(&data->lock);
>> >> +
>> >> + power_supply_changed(data->battery);
>> >> + return IRQ_HANDLED;
>> >> +}
>> >> +
>> >> +static void sc27xx_fgu_disable(void *_data)
>> >> +{
>> >> + struct sc27xx_fgu_data *data = _data;
>> >> +
>> >> + regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
>> >> + regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
>> >> +}
>> >> +
>> >> +static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int capacity)
>> >> +{
>> >> + /*
>> >> + * Get current capacity (mAh) = battery total capacity (mAh) *
>> >> + * current capacity percent (capacity / 100).
>> >> + */
>> >> + int cur_cap = DIV_ROUND_CLOSEST(data->total_cap * capacity, 100);
>> >> +
>> >> + /*
>> >> + * Convert current capacity (mAh) to coulomb counter according to the
>> >> + * formula: 1 mAh =3.6 coulomb.
>> >> + */
>> >> + return DIV_ROUND_CLOSEST(cur_cap * 36, 10);
>> >> +}
>> >> +
>> >> +static int sc27xx_fgu_hw_init(struct sc27xx_fgu_data *data)
>> >> +{
>> >> + struct power_supply_battery_info info = { };
>> >> + struct power_supply_battery_ocv_table *table;
>> >> + int ret, i;
>> >> +
>> >> + ret = power_supply_get_battery_info(data->battery, &info);
>> >> + if (ret) {
>> >> + dev_err(data->dev, "failed to get battery information\n");
>> >> + return ret;
>> >> + }
>> >> +
>> >> + data->total_cap = info.charge_full_design_uah / 1000;
>> >> + data->max_volt = info.constant_charge_voltage_max_uv / 1000;
>> >> + data->internal_resist = info.factory_internal_resistance_uohm / 1000;
>> >> +
>> >> + /*
>> >> + * For SC27XX fuel gauge device, we only use one ocv-capacity
>> >> + * table in normal temperature 20 Celsius.
>> >> + */
>> >> + table = power_supply_find_ocv2cap_table(&info, 20, &data->table_len);
>> >> + if (!table)
>> >> + return -EINVAL;
>> >> +
>> >> + data->cap_table = devm_kzalloc(data->dev,
>> >> + data->table_len * sizeof(*table),
>> >> + GFP_KERNEL);
>> >> + if (!data->cap_table) {
>> >> + power_supply_put_battery_info(data->battery, &info);
>> >> + return -ENOMEM;
>> >> + }
>> >> +
>> >> + for (i = 0; i < data->table_len; i++) {
>> >> + data->cap_table[i].ocv = table[i].ocv / 1000;
>> >> + data->cap_table[i].capacity = table[i].capacity;
>> >> + }
>> >
>> > Don't divide the OCV by 1000. You feed this table into the
>> > generic power-supply function later, which should always
>> > get uV. Instead multiply the ocv parameter in your
>> > power_supply_ocv2cap_simple() call with 1000. This
>> > means you can just use devm_kmemdup() here.
>>
>> Good point. Will change it in next version.
>>
>> >
>> > Some ideas for later (I'm fine with merging the driver
>> > without these changes):
>> >
>> > * Store battery_info directly in private driver data
>> > instead of doing a copy of the temperature table.
>> > * Call power_supply_ocv2cap() with current battery
>> > temperature and let the power-supply core figure
>> > out which ocv-to-capacity curve should be used.
>>
>> I should keep my original method, since we have no temperature table
>> now and only use one room temperature (20 degree). Thanks for your
>> useful comments.
>
> Which should work perfectly fine with power_supply_ocv2cap(). It
> will use the nearest curve, which is always the 20°C one in your
> case. If you add a second temperature curve in the future (i.e.
> because of using the sc27xx fuel gauge with a different battery),
> it would just pick this up automatically. But I'm fine with doing
> this later.

Yes, it can work. But I'd like to do this fix when we need multiple
temperature values in future. Thanks for your understanding.

--
Baolin Wang
Best Regards