Add a power supply driver that supports charge thresholds and behaviour
configuration.
This is a complete rework of
"platform/chrome: cros_ec_framework_laptop: new driver" [0], which used
Framework specific EC commands.
The driver propsed in this series only uses upstream CrOS functionality.
Tested on a Framework 13 AMD, Firmware 3.05.
[0] https://lore.kernel.org/lkml/[email protected]/
Signed-off-by: Thomas Weißschuh <[email protected]>
---
Thomas Weißschuh (3):
platform/chrome: Update binary interface for EC-based charge control
power: supply: add ChromeOS EC based charge control driver
mfd: cros_ec: Register charge control subdevice
MAINTAINERS | 6 +
drivers/mfd/cros_ec_dev.c | 1 +
drivers/power/supply/Kconfig | 12 ++
drivers/power/supply/Makefile | 1 +
drivers/power/supply/cros_charge-control.c | 279 +++++++++++++++++++++++++
include/linux/platform_data/cros_ec_commands.h | 44 +++-
6 files changed, 341 insertions(+), 2 deletions(-)
---
base-commit: 0450d2083be6bdcd18c9535ac50c55266499b2df
change-id: 20240506-cros_ec-charge-control-685617e8ed87
Best regards,
--
Thomas Weißschuh <[email protected]>
The ChromeOS Embedded Controller implements a command to control charge
thresholds and behaviour.
Use it to implement the standard Linux charge_control_start_threshold,
charge_control_end_threshold and charge_behaviour sysfs UAPIs.
The driver is designed to be probed via the cros_ec mfd device.
Signed-off-by: Thomas Weißschuh <[email protected]>
---
MAINTAINERS | 6 +
drivers/power/supply/Kconfig | 12 ++
drivers/power/supply/Makefile | 1 +
drivers/power/supply/cros_charge-control.c | 279 +++++++++++++++++++++++++++++
4 files changed, 298 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index ca389fd49d74..9bccc5683044 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5097,11 +5097,17 @@ S: Maintained
F: Documentation/devicetree/bindings/sound/google,cros-ec-codec.yaml
F: sound/soc/codecs/cros_ec_codec.*
+CHROMEOS EC CHARGE CONTROL
+M: Thomas Weißschuh <[email protected]>
+S: Maintained
+F: drivers/power/supply/cros_charge-control.c
+
CHROMEOS EC SUBDRIVERS
M: Benson Leung <[email protected]>
R: Guenter Roeck <[email protected]>
L: [email protected]
S: Maintained
+F: drivers/power/supply/cros_charge-control.c
F: drivers/power/supply/cros_usbpd-charger.c
N: cros_ec
N: cros-ec
diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index 3e31375491d5..f6321a42aa53 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -860,6 +860,18 @@ config CHARGER_CROS_PCHG
the peripheral charge ports from the EC and converts that into
power_supply properties.
+config CHARGER_CROS_CONTROL
+ tristate "ChromeOS EC based charge control"
+ depends on MFD_CROS_EC_DEV
+ depends on ACPI_BATTERY
+ default MFD_CROS_EC_DEV
+ help
+ Say Y here to enable ChromeOS EC based battery charge control.
+ This driver can manage charge thresholds and behaviour.
+
+ This driver can also be built as a module. If so, the module will be
+ called cros_charge-control.
+
config CHARGER_SC2731
tristate "Spreadtrum SC2731 charger driver"
depends on MFD_SC27XX_PMIC || COMPILE_TEST
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index 58b567278034..31ca6653a564 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -100,6 +100,7 @@ obj-$(CONFIG_CHARGER_TPS65090) += tps65090-charger.o
obj-$(CONFIG_CHARGER_TPS65217) += tps65217_charger.o
obj-$(CONFIG_AXP288_FUEL_GAUGE) += axp288_fuel_gauge.o
obj-$(CONFIG_AXP288_CHARGER) += axp288_charger.o
+obj-$(CONFIG_CHARGER_CROS_CONTROL) += cros_charge-control.o
obj-$(CONFIG_CHARGER_CROS_USBPD) += cros_usbpd-charger.o
obj-$(CONFIG_CHARGER_CROS_PCHG) += cros_peripheral_charger.o
obj-$(CONFIG_CHARGER_SC2731) += sc2731_charger.o
diff --git a/drivers/power/supply/cros_charge-control.c b/drivers/power/supply/cros_charge-control.c
new file mode 100644
index 000000000000..1387c9468c06
--- /dev/null
+++ b/drivers/power/supply/cros_charge-control.c
@@ -0,0 +1,279 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * ChromesOS EC driver for charge control
+ *
+ * Copyright (C) 2024 Thomas Weißschuh <[email protected]>
+ */
+#include <acpi/battery.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_data/cros_ec_commands.h>
+#include <linux/platform_data/cros_ec_proto.h>
+#include <linux/platform_device.h>
+
+#define DRV_NAME "cros-charge-control"
+
+#define EC_CHARGE_CONTROL_BEHAVIOURS (BIT(POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO) | \
+ BIT(POWER_SUPPLY_CHARGE_BEHAVIOUR_INHIBIT_CHARGE) | \
+ BIT(POWER_SUPPLY_CHARGE_BEHAVIOUR_FORCE_DISCHARGE))
+
+/*
+ * Semantics of data *returned* from the EC API and Linux sysfs differ
+ * slightly. To match the expected sysfs API, data is never read back from the
+ * EC but cached in the driver.
+ *
+ * Changes to the EC bypassing the driver will not be reflected in sysfs.
+ * Any change to "charge_behaviour" will synchronize the EC with the driver state.
+ */
+
+struct cros_chctl_priv {
+ struct cros_ec_device *cros_ec;
+ struct acpi_battery_hook battery_hook;
+
+ struct device_attribute start_threshold;
+ struct device_attribute end_threshold;
+ struct device_attribute charge_behaviour;
+ struct attribute *attributes[4];
+ struct attribute_group group;
+
+ enum power_supply_charge_behaviour current_behaviour;
+ u8 current_start_threshold, current_end_threshold;
+};
+
+static int cros_chctl_send_charge_control_cmd(struct cros_ec_device *cros_ec,
+ struct ec_params_charge_control *req)
+{
+ struct {
+ struct cros_ec_command msg;
+ union {
+ struct ec_params_charge_control req;
+ struct ec_response_charge_control resp;
+ } __packed data;
+ } __packed buf = {
+ .msg = {
+ .command = EC_CMD_CHARGE_CONTROL,
+ .version = EC_VER_CHARGE_CONTROL,
+ .insize = sizeof(buf.data.resp),
+ .outsize = sizeof(buf.data.req),
+ },
+ .data.req = *req,
+ };
+
+ return cros_ec_cmd_xfer_status(cros_ec, &buf.msg);
+}
+
+static int cros_chctl_configure_ec(struct device *dev, struct cros_chctl_priv *priv)
+{
+ struct ec_params_charge_control req = { };
+
+ req.cmd = EC_CHARGE_CONTROL_CMD_SET;
+
+ switch (priv->current_behaviour) {
+ case POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO:
+ req.mode = CHARGE_CONTROL_NORMAL;
+ break;
+ case POWER_SUPPLY_CHARGE_BEHAVIOUR_INHIBIT_CHARGE:
+ req.mode = CHARGE_CONTROL_IDLE;
+ break;
+ case POWER_SUPPLY_CHARGE_BEHAVIOUR_FORCE_DISCHARGE:
+ req.mode = CHARGE_CONTROL_DISCHARGE;
+ break;
+ default:
+ dev_warn_ratelimited(dev, "Unexpected behaviour %d", priv->current_behaviour);
+ return -EINVAL;
+ }
+
+ if (priv->current_behaviour == POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO &&
+ !(priv->current_start_threshold == 0 && priv->current_end_threshold == 100)) {
+ req.sustain_soc.lower = priv->current_start_threshold;
+ req.sustain_soc.upper = priv->current_end_threshold;
+ } else {
+ /* Disable charging limits */
+ req.sustain_soc.lower = -1;
+ req.sustain_soc.upper = -1;
+ }
+
+ return cros_chctl_send_charge_control_cmd(priv->cros_ec, &req);
+}
+
+static ssize_t cros_chctl_store_threshold(struct device *dev,
+ struct cros_chctl_priv *priv,
+ int is_end_threshold,
+ const char *buf, size_t count)
+{
+ int ret, val;
+
+ ret = kstrtoint(buf, 10, &val);
+ if (ret < 0)
+ return ret;
+ if (val < 1 || val > 100)
+ return -EINVAL;
+
+ if (is_end_threshold) {
+ if (val <= priv->current_start_threshold)
+ return -EINVAL;
+ priv->current_end_threshold = val;
+ } else {
+ if (val >= priv->current_end_threshold)
+ return -EINVAL;
+ priv->current_start_threshold = val;
+ }
+
+ if (priv->current_behaviour == POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO) {
+ ret = cros_chctl_configure_ec(dev, priv);
+ if (ret < 0)
+ return ret;
+ }
+
+ return count;
+}
+
+static ssize_t charge_control_start_threshold_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct cros_chctl_priv *priv = container_of(attr, struct cros_chctl_priv, start_threshold);
+
+ return sysfs_emit(buf, "%u\n", (unsigned int)priv->current_start_threshold);
+}
+
+static ssize_t charge_control_start_threshold_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct cros_chctl_priv *priv = container_of(attr, struct cros_chctl_priv, start_threshold);
+
+ return cros_chctl_store_threshold(dev, priv, 0, buf, count);
+}
+
+static ssize_t charge_control_end_threshold_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct cros_chctl_priv *priv = container_of(attr, struct cros_chctl_priv, end_threshold);
+
+ return sysfs_emit(buf, "%u\n", (unsigned int)priv->current_end_threshold);
+}
+
+static ssize_t charge_control_end_threshold_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct cros_chctl_priv *priv = container_of(attr, struct cros_chctl_priv, end_threshold);
+
+ return cros_chctl_store_threshold(dev, priv, 1, buf, count);
+}
+
+static ssize_t charge_behaviour_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct cros_chctl_priv *priv = container_of(attr, struct cros_chctl_priv, charge_behaviour);
+
+ return power_supply_charge_behaviour_show(dev, EC_CHARGE_CONTROL_BEHAVIOURS,
+ priv->current_behaviour, buf);
+}
+
+static ssize_t charge_behaviour_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct cros_chctl_priv *priv = container_of(attr, struct cros_chctl_priv, charge_behaviour);
+ enum power_supply_charge_behaviour behaviour;
+ int ret;
+
+ behaviour = power_supply_charge_behaviour_parse(EC_CHARGE_CONTROL_BEHAVIOURS, buf);
+ if (behaviour < 0)
+ return behaviour;
+
+ priv->current_behaviour = behaviour;
+
+ ret = cros_chctl_configure_ec(dev, priv);
+ if (ret < 0)
+ return ret;
+
+ return count;
+}
+
+static int cros_chctl_add_battery(struct power_supply *battery, struct acpi_battery_hook *hook)
+{
+ struct cros_chctl_priv *priv = container_of(hook, struct cros_chctl_priv, battery_hook);
+
+ return device_add_group(&battery->dev, &priv->group);
+}
+
+static int cros_chctl_remove_battery(struct power_supply *battery, struct acpi_battery_hook *hook)
+{
+ struct cros_chctl_priv *priv = container_of(hook, struct cros_chctl_priv, battery_hook);
+
+ device_remove_group(&battery->dev, &priv->group);
+
+ return 0;
+}
+
+static int cros_chctl_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent);
+ struct cros_ec_device *cros_ec = ec_dev->ec_dev;
+ struct cros_chctl_priv *priv;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->cros_ec = cros_ec;
+ priv->start_threshold = (struct device_attribute)__ATTR_RW(charge_control_start_threshold);
+ priv->end_threshold = (struct device_attribute)__ATTR_RW(charge_control_end_threshold);
+ priv->charge_behaviour = (struct device_attribute)__ATTR_RW(charge_behaviour);
+ priv->attributes[0] = &priv->start_threshold.attr;
+ priv->attributes[1] = &priv->end_threshold.attr;
+ priv->attributes[2] = &priv->charge_behaviour.attr;
+ priv->attributes[3] = NULL;
+ priv->group.attrs = priv->attributes;
+
+ priv->battery_hook.name = dev_name(dev),
+ priv->battery_hook.add_battery = cros_chctl_add_battery,
+ priv->battery_hook.remove_battery = cros_chctl_remove_battery,
+
+ priv->current_behaviour = POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO;
+ priv->current_start_threshold = 0;
+ priv->current_end_threshold = 100;
+
+ /* Bring EC into well-known state and validate command availability */
+ ret = cros_chctl_configure_ec(dev, priv);
+ if (ret == -EOPNOTSUPP)
+ return -ENODEV;
+ else if (ret < 0)
+ return ret;
+
+ battery_hook_register(&priv->battery_hook);
+
+ platform_set_drvdata(pdev, priv);
+
+ return 0;
+}
+
+static int cros_chctl_remove(struct platform_device *pdev)
+{
+ struct cros_chctl_priv *priv = platform_get_drvdata(pdev);
+
+ battery_hook_unregister(&priv->battery_hook);
+
+ return 0;
+}
+
+static const struct platform_device_id cros_chctl_id[] = {
+ { DRV_NAME, 0 },
+ { }
+};
+
+static struct platform_driver cros_chctl_driver = {
+ .driver.name = DRV_NAME,
+ .probe = cros_chctl_probe,
+ .remove = cros_chctl_remove,
+ .id_table = cros_chctl_id,
+};
+module_platform_driver(cros_chctl_driver);
+
+MODULE_DEVICE_TABLE(platform, cros_chctl_id);
+MODULE_DESCRIPTION("ChromeOS EC charge control");
+MODULE_AUTHOR("Thomas Weißschuh <[email protected]>");
+MODULE_LICENSE("GPL");
--
2.45.1
The charge-control command v2 is more featureful than v1, it
additionally supports charge thresholds.
While v3 is also defined, it is very recent and not implemented widely.
The definitions were imported from ChromeOS EC commit
9de7e85d14fb ("test/timer: Increase sleep time error for Helipilot"),
which is the commit just before the introduction of v3 of the protocol.
Signed-off-by: Thomas Weißschuh <[email protected]>
---
include/linux/platform_data/cros_ec_commands.h | 44 ++++++++++++++++++++++++--
1 file changed, 42 insertions(+), 2 deletions(-)
diff --git a/include/linux/platform_data/cros_ec_commands.h b/include/linux/platform_data/cros_ec_commands.h
index ecc47d5fe239..75521e2b9bb4 100644
--- a/include/linux/platform_data/cros_ec_commands.h
+++ b/include/linux/platform_data/cros_ec_commands.h
@@ -3809,16 +3809,56 @@ struct ec_params_i2c_write {
* discharge the battery.
*/
#define EC_CMD_CHARGE_CONTROL 0x0096
-#define EC_VER_CHARGE_CONTROL 1
+#define EC_VER_CHARGE_CONTROL 2
enum ec_charge_control_mode {
CHARGE_CONTROL_NORMAL = 0,
CHARGE_CONTROL_IDLE,
CHARGE_CONTROL_DISCHARGE,
+ /* Add no more entry below. */
+ CHARGE_CONTROL_COUNT,
+};
+
+#define EC_CHARGE_MODE_TEXT \
+ { \
+ [CHARGE_CONTROL_NORMAL] = "NORMAL", \
+ [CHARGE_CONTROL_IDLE] = "IDLE", \
+ [CHARGE_CONTROL_DISCHARGE] = "DISCHARGE", \
+ }
+
+enum ec_charge_control_cmd {
+ EC_CHARGE_CONTROL_CMD_SET = 0,
+ EC_CHARGE_CONTROL_CMD_GET,
};
struct ec_params_charge_control {
- uint32_t mode; /* enum charge_control_mode */
+ uint32_t mode; /* enum charge_control_mode */
+
+ /* Below are the fields added in V2. */
+ uint8_t cmd; /* enum ec_charge_control_cmd. */
+ uint8_t reserved;
+ /*
+ * Lower and upper thresholds for battery sustainer. This struct isn't
+ * named to avoid tainting foreign projects' name spaces.
+ *
+ * If charge mode is explicitly set (e.g. DISCHARGE), battery sustainer
+ * will be disabled. To disable battery sustainer, set mode=NORMAL,
+ * lower=-1, upper=-1.
+ */
+ struct {
+ int8_t lower; /* Display SoC in percentage. */
+ int8_t upper; /* Display SoC in percentage. */
+ } sustain_soc;
+} __ec_align4;
+
+/* Added in v2 */
+struct ec_response_charge_control {
+ uint32_t mode; /* enum charge_control_mode */
+ struct { /* Battery sustainer thresholds */
+ int8_t lower;
+ int8_t upper;
+ } sustain_soc;
+ uint16_t reserved;
} __ec_align4;
/*****************************************************************************/
--
2.45.1