Add driver and device tree bindings support for Maxim max31329 real
time clock.
Changes since v2.
1. Removed log messages from error cases.
2. Removed OSF check from _read_alarm(), _set_alarm(), _set_time().
3. Removed CLKOUT pin initialization in probe() since it is configurable
during runtime.
4. Configure wakeup support when interrupt is successfully configured
or if the 'wakeup-source' parameter present in DT.
5. Added check for 'years' in _set_alarm so that it doesn't' cross current
century.
Changes since v1.
1. Move 'allOf' after 'maintainers' in DT.
2. Add 'wakeup-source' into device tree bindings.
3. Add wakeup support depending on the 'wakeup-source' parameter from DT.
4. Remove unused 'dev' member from device private data structure.
5. Use '__maybe_unused' attribute for of_device_id table.
6. Initialize local variable 'events' to 0 in interrupt handler.
Reported-by: kernel test robot <[email protected]>
Reported-by: Dan Carpenter <[email protected]>
7. Add Reviewed-by tag for device tree bindings.
Jagath Jog J (2):
dt-bindings: rtc: add Maxim max31329 rtc device tree bindings
rtc: max31329: Add Maxim max31329 real time clock
.../bindings/rtc/maxim,max31329.yaml | 61 +++
MAINTAINERS | 7 +
drivers/rtc/Kconfig | 10 +
drivers/rtc/Makefile | 1 +
drivers/rtc/rtc-max31329.c | 507 ++++++++++++++++++
5 files changed, 586 insertions(+)
create mode 100644 Documentation/devicetree/bindings/rtc/maxim,max31329.yaml
create mode 100644 drivers/rtc/rtc-max31329.c
--
2.17.1
Add driver support for I2C based Maxim max31329 real time clock.
Signed-off-by: Jagath Jog J <[email protected]>
---
MAINTAINERS | 7 +
drivers/rtc/Kconfig | 10 +
drivers/rtc/Makefile | 1 +
drivers/rtc/rtc-max31329.c | 507 +++++++++++++++++++++++++++++++++++++
4 files changed, 525 insertions(+)
create mode 100644 drivers/rtc/rtc-max31329.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 7032fcb0fd0f..d92ddab0958d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12478,6 +12478,13 @@ F: include/linux/mfd/max14577*.h
F: include/linux/mfd/max77686*.h
F: include/linux/mfd/max77693*.h
+MAXIM MAX31329 RTC DRIVER
+M: Jagath Jog J <[email protected]>
+L: [email protected]
+S: Maintained
+F: Documentation/devicetree/bindings/rtc/maxim,max31329.yaml
+F: drivers/rtc/max31329.c
+
MAXIRADIO FM RADIO RECEIVER DRIVER
M: Hans Verkuil <[email protected]>
L: [email protected]
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index b8de25118ad0..d02cba94e121 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -393,6 +393,16 @@ config RTC_DRV_NCT3018Y
This driver can also be built as a module, if so, the module will be
called "rtc-nct3018y".
+config RTC_DRV_MAX31329
+ tristate "Maxim MAX31329"
+ select REGMAP_I2C
+ help
+ If you say yes here you will get support for the
+ RTC of Maxim MAX31329.
+
+ This driver can also be build as a module. If so, the module
+ will be called rtc-max31329.
+
config RTC_DRV_RK808
tristate "Rockchip RK805/RK808/RK809/RK817/RK818 RTC"
depends on MFD_RK808
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index aab22bc63432..741216d2f9ca 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -97,6 +97,7 @@ obj-$(CONFIG_RTC_DRV_MAX8907) += rtc-max8907.o
obj-$(CONFIG_RTC_DRV_MAX8925) += rtc-max8925.o
obj-$(CONFIG_RTC_DRV_MAX8997) += rtc-max8997.o
obj-$(CONFIG_RTC_DRV_MAX8998) += rtc-max8998.o
+obj-$(CONFIG_RTC_DRV_MAX31329) += rtc-max31329.o
obj-$(CONFIG_RTC_DRV_MESON_VRTC)+= rtc-meson-vrtc.o
obj-$(CONFIG_RTC_DRV_MC13XXX) += rtc-mc13xxx.o
obj-$(CONFIG_RTC_DRV_MCP795) += rtc-mcp795.o
diff --git a/drivers/rtc/rtc-max31329.c b/drivers/rtc/rtc-max31329.c
new file mode 100644
index 000000000000..fbbe439a9a3b
--- /dev/null
+++ b/drivers/rtc/rtc-max31329.c
@@ -0,0 +1,507 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * RTC driver for the Maxim MAX31329 Real-Time Clock
+ * Copyright (c) 2022 Jagath Jog J
+ *
+ * Datasheet: https://datasheets.maximintegrated.com/en/ds/MAX31329.pdf
+ *
+ */
+
+#include <linux/bcd.h>
+#include <linux/bitfield.h>
+#include <linux/clk-provider.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/rtc.h>
+
+/* Register map */
+/* Config registers */
+#define MAX31329_STATUS_REG 0x00
+#define MAX31329_STATUS_A1F BIT(0)
+#define MAX31329_STATUS_OSF BIT(6)
+#define MAX31329_INT_EN_REG 0x01
+#define MAX31329_INT_EN_A1IE BIT(0)
+#define MAX31329_RTC_RESET_REG 0x02
+#define MAX31329_RTC_CONFIG1_REG 0x03
+#define MAX31329_RTC_CONFIG2_REG 0x04
+#define MAX31329_RTC_CONFIG2_ENCLKIN BIT(2)
+#define MAX31329_RTC_CONFIG2_ENCLKO BIT(7)
+#define MAX31329_RTC_CFG2_CLKOHZ_MSK GENMASK(6, 5)
+#define MAX31329_TIMER_CONFIG_REG 0x05
+
+/* Watch registers */
+#define MAX31329_SECONDS_REG 0x06
+#define MAX31329_MINUTES_REG 0x07
+#define MAX31329_HOURS_REG 0x08
+#define MAX31329_HOURS_F24_12 BIT(6)
+#define MAX31329_HOURS_AM_PM BIT(5)
+#define MAX31329_DAY_REG 0x09
+#define MAX31329_DATE_REG 0x0A
+#define MAX31329_MONTH_REG 0x0B
+#define MAX31329_MONTH_CENTURY BIT(7)
+#define MAX31329_YEAR_REG 0x0C
+#define MAX31329_WATCH_SEC_LEN 0x07
+#define REG_TO_OFFSET(_REG) ((_REG) - MAX31329_SECONDS_REG)
+
+/* Alarm registers */
+#define MAX31329_ALM1_SEC_REG 0x0D
+#define MAX31329_ALM1_MIN_REG 0x0E
+#define MAX31329_ALM1_HRS_REG 0x0F
+#define MAX31329_ALM1_DAY_DATE_REG 0x10
+#define MAX31329_ALM1_MON_REG 0x11
+#define MAX31329_ALM1_YEAR_REG 0x12
+#define MAX31329_ALM1_SEC_LEN 0x06
+
+#define MAX31329_PWR_MGMT_REG 0x18
+#define MAX31329_TRICKLE_REG 0x19
+#define MAX31329_TRICKLE_EN BIT(7)
+#define MAX31329_TRICKLE_DIODE_EN BIT(2)
+#define MAX31329_D_TRICKLE_OHMS GENMASK(3, 0)
+
+/* Ram registers */
+#define MAX31329_RAM0_START_REG 0x22
+#define MAX31329_RAM0_END_REG 0x61
+
+struct max31329_data {
+ struct regmap *regmap;
+ struct rtc_device *rtc;
+ int irq;
+#ifdef CONFIG_COMMON_CLK
+ struct clk_hw clkout_hw;
+#endif
+};
+
+/* resistance in kohms */
+static u32 max31329_trickle_ohms[] = {
+ 3000,
+ 6000,
+ 11000
+};
+
+static const struct regmap_config config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = MAX31329_RAM0_END_REG,
+};
+
+static int max31329_get_osc_status(struct device *dev)
+{
+ struct max31329_data *max31329 = dev_get_drvdata(dev);
+ unsigned int status;
+ int ret;
+
+ ret = regmap_read(max31329->regmap, MAX31329_STATUS_REG, &status);
+ if (ret)
+ return ret;
+
+ if (status & MAX31329_STATUS_OSF)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int max31329_alarm_irq_enable(struct device *dev, unsigned int enable)
+{
+ struct max31329_data *max31329 = dev_get_drvdata(dev);
+
+ return regmap_update_bits(max31329->regmap, MAX31329_INT_EN_REG,
+ MAX31329_INT_EN_A1IE,
+ enable ? MAX31329_INT_EN_A1IE : 0);
+}
+
+static int max31329_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct max31329_data *max31329 = dev_get_drvdata(dev);
+ struct rtc_time *const tm = &alarm->time;
+ unsigned int aie_en, aie_flag;
+ int ret;
+ u8 regs[6];
+
+ ret = regmap_bulk_read(max31329->regmap, MAX31329_ALM1_SEC_REG, regs,
+ MAX31329_ALM1_SEC_LEN);
+ if (ret)
+ return ret;
+
+ ret = regmap_read(max31329->regmap, MAX31329_INT_EN_REG, &aie_en);
+ if (ret)
+ return ret;
+
+ ret = regmap_read(max31329->regmap, MAX31329_STATUS_REG, &aie_flag);
+ if (ret)
+ return ret;
+
+ tm->tm_sec = bcd2bin(regs[REG_TO_OFFSET(MAX31329_SECONDS_REG)] & 0x7f);
+ tm->tm_min = bcd2bin(regs[REG_TO_OFFSET(MAX31329_MINUTES_REG)] & 0x7f);
+ tm->tm_hour = bcd2bin(regs[REG_TO_OFFSET(MAX31329_HOURS_REG)] & 0x3f);
+ tm->tm_mday = bcd2bin(regs[REG_TO_OFFSET(MAX31329_DATE_REG) - 1] & 0x3f);
+ tm->tm_mon = bcd2bin(regs[REG_TO_OFFSET(MAX31329_MONTH_REG) - 1] &
+ 0x1f) - 1;
+ tm->tm_year = bcd2bin(regs[REG_TO_OFFSET(MAX31329_YEAR_REG) - 1]) + 200;
+
+ alarm->enabled = FIELD_GET(MAX31329_INT_EN_A1IE, aie_en);
+ alarm->pending = FIELD_GET(MAX31329_STATUS_A1F, aie_flag) &&
+ alarm->enabled;
+
+ return 0;
+}
+
+static int max31329_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct max31329_data *max31329 = dev_get_drvdata(dev);
+ const struct rtc_time *tm = &alrm->time;
+ u8 regs[6], year;
+ int ret;
+
+ regs[REG_TO_OFFSET(MAX31329_SECONDS_REG)] = bin2bcd(tm->tm_sec) & 0x7F;
+ regs[REG_TO_OFFSET(MAX31329_MINUTES_REG)] = bin2bcd(tm->tm_min) & 0x7f;
+ regs[REG_TO_OFFSET(MAX31329_HOURS_REG)] = bin2bcd(tm->tm_hour) & 0x3f;
+ regs[REG_TO_OFFSET(MAX31329_DATE_REG) - 1] = bin2bcd(tm->tm_mday) & 0x3f;
+ regs[REG_TO_OFFSET(MAX31329_MONTH_REG) - 1] = bin2bcd(tm->tm_mon + 1) & 0x1f;
+
+ if (tm->tm_year >= 200)
+ return -EINVAL;
+
+ year = bin2bcd(tm->tm_year - 100);
+ regs[REG_TO_OFFSET(MAX31329_YEAR_REG) - 1] = year;
+
+ ret = regmap_bulk_write(max31329->regmap, MAX31329_ALM1_SEC_REG, regs,
+ MAX31329_ALM1_SEC_LEN);
+ if (ret)
+ return ret;
+
+ return max31329_alarm_irq_enable(dev, alrm->enabled);
+}
+
+static int max31329_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct max31329_data *max31329 = dev_get_drvdata(dev);
+ u8 data[7], century = 0;
+ int ret;
+
+ ret = max31329_get_osc_status(dev);
+ if (ret)
+ return ret;
+
+ ret = regmap_bulk_read(max31329->regmap, MAX31329_SECONDS_REG, data,
+ sizeof(data));
+ if (ret)
+ return ret;
+
+ tm->tm_sec = bcd2bin(data[REG_TO_OFFSET(MAX31329_SECONDS_REG)] & 0x7f);
+ tm->tm_min = bcd2bin(data[REG_TO_OFFSET(MAX31329_MINUTES_REG)] & 0x7f);
+ tm->tm_hour = bcd2bin(data[REG_TO_OFFSET(MAX31329_HOURS_REG)] & 0x3f);
+ /* Day of the week in linux range is 0~6 while 1~7 in RTC chip */
+ tm->tm_wday = bcd2bin(data[REG_TO_OFFSET(MAX31329_DAY_REG)] & 0x07) - 1;
+ tm->tm_mday = bcd2bin(data[REG_TO_OFFSET(MAX31329_DATE_REG)] & 0x3f);
+ /* linux tm_mon range:0~11, while month range is 1~12 in RTC chip */
+ tm->tm_mon = bcd2bin(data[REG_TO_OFFSET(MAX31329_MONTH_REG)] & 0x1f) - 1;
+
+ century = data[REG_TO_OFFSET(MAX31329_MONTH_REG)] & MAX31329_MONTH_CENTURY;
+ tm->tm_year = bcd2bin(data[REG_TO_OFFSET(MAX31329_YEAR_REG)]) +
+ (century ? 200 : 100);
+
+ return 0;
+}
+
+static int max31329_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct max31329_data *max31329 = dev_get_drvdata(dev);
+ u8 regs[7];
+
+ regs[REG_TO_OFFSET(MAX31329_SECONDS_REG)] = bin2bcd(tm->tm_sec);
+ regs[REG_TO_OFFSET(MAX31329_MINUTES_REG)] = bin2bcd(tm->tm_min);
+ regs[REG_TO_OFFSET(MAX31329_HOURS_REG)] = bin2bcd(tm->tm_hour);
+ regs[REG_TO_OFFSET(MAX31329_DAY_REG)] = bin2bcd(tm->tm_wday + 1);
+ regs[REG_TO_OFFSET(MAX31329_DATE_REG)] = bin2bcd(tm->tm_mday);
+ regs[REG_TO_OFFSET(MAX31329_MONTH_REG)] = bin2bcd(tm->tm_mon + 1);
+
+ if (tm->tm_year >= 200)
+ regs[REG_TO_OFFSET(MAX31329_MONTH_REG)] |= MAX31329_MONTH_CENTURY;
+ regs[REG_TO_OFFSET(MAX31329_YEAR_REG)] = bin2bcd(tm->tm_year % 100);
+
+ return regmap_bulk_write(max31329->regmap, MAX31329_SECONDS_REG, regs,
+ MAX31329_WATCH_SEC_LEN);
+}
+
+static const struct rtc_class_ops max31329_rtc_ops = {
+ .read_time = max31329_read_time,
+ .set_time = max31329_set_time,
+ .read_alarm = max31329_read_alarm,
+ .set_alarm = max31329_set_alarm,
+ .alarm_irq_enable = max31329_alarm_irq_enable,
+};
+
+static irqreturn_t max31329_irq_handler(int irq, void *dev_id)
+{
+ struct device *dev = dev_id;
+ struct max31329_data *max31329 = dev_get_drvdata(dev);
+ unsigned int flags, controls;
+ unsigned long events = 0;
+ int ret;
+
+ ret = regmap_read(max31329->regmap, MAX31329_INT_EN_REG, &controls);
+ if (ret)
+ return IRQ_NONE;
+
+ ret = regmap_read(max31329->regmap, MAX31329_STATUS_REG, &flags);
+ if (ret)
+ return IRQ_NONE;
+
+ if (flags & MAX31329_STATUS_A1F) {
+ flags &= ~MAX31329_STATUS_A1F;
+ controls &= ~MAX31329_INT_EN_A1IE;
+ events = RTC_AF | RTC_IRQF;
+ }
+
+ if (events) {
+ rtc_update_irq(max31329->rtc, 1, events);
+ regmap_write(max31329->regmap, MAX31329_STATUS_REG, flags);
+ regmap_write(max31329->regmap, MAX31329_INT_EN_REG, controls);
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+}
+
+static void max31329_trickle_config(struct device *dev)
+{
+ struct max31329_data *max31329 = dev_get_drvdata(dev);
+ u8 trickle_reg;
+ int ret, i;
+ u32 ohms;
+
+ /* Configure the trickle charger. */
+ ret = device_property_read_u32(dev, "trickle-resistor-ohms", &ohms);
+ if (ret)
+ return;
+
+ trickle_reg = MAX31329_TRICKLE_EN;
+ for (i = 1; i <= ARRAY_SIZE(max31329_trickle_ohms); i++) {
+ if (max31329_trickle_ohms[i - 1] == ohms) {
+ trickle_reg |= i;
+ regmap_write(max31329->regmap, MAX31329_TRICKLE_REG,
+ trickle_reg);
+ }
+ }
+}
+
+static int max31329_nvram_write(void *priv, unsigned int offset, void *val,
+ size_t bytes)
+{
+ struct regmap *max31329_regmap = (struct regmap *)priv;
+
+ return regmap_bulk_write(max31329_regmap,
+ MAX31329_RAM0_START_REG + offset,
+ val, bytes);
+}
+
+static int max31329_nvram_read(void *priv, unsigned int offset, void *val,
+ size_t bytes)
+{
+ struct regmap *max31329_regmap = (struct regmap *)priv;
+
+ return regmap_bulk_read(max31329_regmap,
+ MAX31329_RAM0_START_REG + offset,
+ val, bytes);
+}
+
+#ifdef CONFIG_COMMON_CLK
+#define clkout_hw_to_max31329(hw) container_of(hw, struct max31329_data, clkout_hw)
+
+static int clkout_rates[] = {
+ 1,
+ 4096,
+ 8192,
+ 32768
+};
+
+static unsigned long max31329_clkout_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct max31329_data *max31329 = clkout_hw_to_max31329(hw);
+ int clkout, ret;
+
+ ret = regmap_read(max31329->regmap, MAX31329_RTC_CONFIG2_REG, &clkout);
+ if (ret)
+ return 0;
+
+ return clkout_rates[FIELD_GET(MAX31329_RTC_CFG2_CLKOHZ_MSK, clkout)];
+}
+
+static long max31329_clkout_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
+ if (clkout_rates[i] >= rate)
+ return clkout_rates[i];
+
+ return 0;
+}
+
+static int max31329_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct max31329_data *max31329 = clkout_hw_to_max31329(hw);
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
+ if (rate == clkout_rates[i])
+ return regmap_update_bits(max31329->regmap,
+ MAX31329_RTC_CONFIG2_REG,
+ MAX31329_RTC_CFG2_CLKOHZ_MSK,
+ FIELD_PREP(MAX31329_RTC_CFG2_CLKOHZ_MSK,
+ i));
+ return -EINVAL;
+}
+
+static int max31329_clkout_prepare(struct clk_hw *hw)
+{
+ struct max31329_data *max31329 = clkout_hw_to_max31329(hw);
+
+ return regmap_update_bits(max31329->regmap, MAX31329_RTC_CONFIG2_REG,
+ MAX31329_RTC_CONFIG2_ENCLKO,
+ MAX31329_RTC_CONFIG2_ENCLKO);
+}
+
+static void max31329_clkout_unprepare(struct clk_hw *hw)
+{
+ struct max31329_data *max31329 = clkout_hw_to_max31329(hw);
+
+ regmap_update_bits(max31329->regmap, MAX31329_RTC_CONFIG2_REG,
+ MAX31329_RTC_CONFIG2_ENCLKO,
+ FIELD_PREP(MAX31329_RTC_CONFIG2_ENCLKO, 0));
+}
+
+static int max31329_clkout_is_prepared(struct clk_hw *hw)
+{
+ struct max31329_data *max31329 = clkout_hw_to_max31329(hw);
+ int clkout, ret;
+
+ ret = regmap_read(max31329->regmap, MAX31329_RTC_CONFIG2_REG, &clkout);
+ if (ret)
+ return ret;
+
+ return !!(clkout & MAX31329_RTC_CONFIG2_ENCLKO);
+}
+
+static const struct clk_ops max31329_clkout_ops = {
+ .prepare = max31329_clkout_prepare,
+ .unprepare = max31329_clkout_unprepare,
+ .is_prepared = max31329_clkout_is_prepared,
+ .recalc_rate = max31329_clkout_recalc_rate,
+ .round_rate = max31329_clkout_round_rate,
+ .set_rate = max31329_clkout_set_rate,
+};
+
+static struct clk *max31329_clkout_register_clk(struct max31329_data *max31329,
+ struct i2c_client *client)
+{
+ struct device_node *node = client->dev.of_node;
+ struct clk_init_data init;
+ struct clk *clk;
+
+ init.name = "max31329-clkout";
+ init.ops = &max31329_clkout_ops;
+ init.flags = 0;
+ init.parent_names = NULL;
+ init.num_parents = 0;
+ max31329->clkout_hw.init = &init;
+
+ /* optional override of the clockname */
+ of_property_read_string(node, "clock-output-names", &init.name);
+
+ clk = devm_clk_register(&client->dev, &max31329->clkout_hw);
+ if (!IS_ERR(clk))
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+
+ return clk;
+}
+#endif
+
+static int max31329_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct max31329_data *max31329;
+ int ret;
+ struct nvmem_config nvmem_cfg = {
+ .name = "max31329_nvram",
+ .word_size = 1,
+ .stride = 1,
+ .size = 64,
+ .type = NVMEM_TYPE_BATTERY_BACKED,
+ .reg_read = max31329_nvram_read,
+ .reg_write = max31329_nvram_write,
+ };
+
+ max31329 = devm_kzalloc(&client->dev, sizeof(*max31329), GFP_KERNEL);
+ if (!max31329)
+ return -ENOMEM;
+
+ max31329->regmap = devm_regmap_init_i2c(client, &config);
+ if (IS_ERR(max31329->regmap))
+ return PTR_ERR(max31329->regmap);
+
+ dev_set_drvdata(&client->dev, max31329);
+
+ max31329->rtc = devm_rtc_allocate_device(&client->dev);
+ if (IS_ERR(max31329->rtc))
+ return PTR_ERR(max31329->rtc);
+
+ max31329->rtc->ops = &max31329_rtc_ops;
+ max31329->irq = client->irq;
+ max31329->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
+ max31329->rtc->range_max = RTC_TIMESTAMP_END_2199;
+
+ if (max31329->irq) {
+ ret = devm_request_threaded_irq(&client->dev, max31329->irq,
+ NULL, max31329_irq_handler,
+ IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+ "max31329", &client->dev);
+ if (ret)
+ return ret;
+ } else {
+ clear_bit(RTC_FEATURE_ALARM, max31329->rtc->features);
+ clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, max31329->rtc->features);
+ }
+
+ if (max31329->irq || device_property_read_bool(&client->dev,
+ "wakeup-source"))
+ device_init_wakeup(&client->dev, true);
+
+ ret = devm_rtc_register_device(max31329->rtc);
+ if (ret)
+ return ret;
+
+ max31329_trickle_config(&client->dev);
+
+ nvmem_cfg.priv = max31329->regmap;
+ devm_rtc_nvmem_register(max31329->rtc, &nvmem_cfg);
+
+#ifdef CONFIG_COMMON_CLK
+ max31329_clkout_register_clk(max31329, client);
+#endif
+
+ return 0;
+}
+
+static const __maybe_unused struct of_device_id max31329_of_match[] = {
+ { .compatible = "maxim,max31329", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, max31329_of_match);
+
+static struct i2c_driver max31329_driver = {
+ .driver = {
+ .name = "rtc-max31329",
+ .of_match_table = of_match_ptr(max31329_of_match),
+ },
+ .probe = max31329_probe,
+};
+module_i2c_driver(max31329_driver);
+
+MODULE_AUTHOR("Jagath Jog J <[email protected]>");
+MODULE_DESCRIPTION("Maxim MAX31329 RTC driver");
+MODULE_LICENSE("GPL");
--
2.17.1
Hi Alexandre,
Is there any change needed for this v3 series?
Thanks,
Jagath
On Sat, Sep 24, 2022 at 12:24 AM Jagath Jog J <[email protected]> wrote:
>
> Add driver support for I2C based Maxim max31329 real time clock.
>
> Signed-off-by: Jagath Jog J <[email protected]>
> ---
> MAINTAINERS | 7 +
> drivers/rtc/Kconfig | 10 +
> drivers/rtc/Makefile | 1 +
> drivers/rtc/rtc-max31329.c | 507 +++++++++++++++++++++++++++++++++++++
> 4 files changed, 525 insertions(+)
> create mode 100644 drivers/rtc/rtc-max31329.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 7032fcb0fd0f..d92ddab0958d 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -12478,6 +12478,13 @@ F: include/linux/mfd/max14577*.h
> F: include/linux/mfd/max77686*.h
> F: include/linux/mfd/max77693*.h
>
> +MAXIM MAX31329 RTC DRIVER
> +M: Jagath Jog J <[email protected]>
> +L: [email protected]
> +S: Maintained
> +F: Documentation/devicetree/bindings/rtc/maxim,max31329.yaml
> +F: drivers/rtc/max31329.c
> +
> MAXIRADIO FM RADIO RECEIVER DRIVER
> M: Hans Verkuil <[email protected]>
> L: [email protected]
> diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
> index b8de25118ad0..d02cba94e121 100644
> --- a/drivers/rtc/Kconfig
> +++ b/drivers/rtc/Kconfig
> @@ -393,6 +393,16 @@ config RTC_DRV_NCT3018Y
> This driver can also be built as a module, if so, the module will be
> called "rtc-nct3018y".
>
> +config RTC_DRV_MAX31329
> + tristate "Maxim MAX31329"
> + select REGMAP_I2C
> + help
> + If you say yes here you will get support for the
> + RTC of Maxim MAX31329.
> +
> + This driver can also be build as a module. If so, the module
> + will be called rtc-max31329.
> +
> config RTC_DRV_RK808
> tristate "Rockchip RK805/RK808/RK809/RK817/RK818 RTC"
> depends on MFD_RK808
> diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
> index aab22bc63432..741216d2f9ca 100644
> --- a/drivers/rtc/Makefile
> +++ b/drivers/rtc/Makefile
> @@ -97,6 +97,7 @@ obj-$(CONFIG_RTC_DRV_MAX8907) += rtc-max8907.o
> obj-$(CONFIG_RTC_DRV_MAX8925) += rtc-max8925.o
> obj-$(CONFIG_RTC_DRV_MAX8997) += rtc-max8997.o
> obj-$(CONFIG_RTC_DRV_MAX8998) += rtc-max8998.o
> +obj-$(CONFIG_RTC_DRV_MAX31329) += rtc-max31329.o
> obj-$(CONFIG_RTC_DRV_MESON_VRTC)+= rtc-meson-vrtc.o
> obj-$(CONFIG_RTC_DRV_MC13XXX) += rtc-mc13xxx.o
> obj-$(CONFIG_RTC_DRV_MCP795) += rtc-mcp795.o
> diff --git a/drivers/rtc/rtc-max31329.c b/drivers/rtc/rtc-max31329.c
> new file mode 100644
> index 000000000000..fbbe439a9a3b
> --- /dev/null
> +++ b/drivers/rtc/rtc-max31329.c
> @@ -0,0 +1,507 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * RTC driver for the Maxim MAX31329 Real-Time Clock
> + * Copyright (c) 2022 Jagath Jog J
> + *
> + * Datasheet: https://datasheets.maximintegrated.com/en/ds/MAX31329.pdf
> + *
> + */
> +
> +#include <linux/bcd.h>
> +#include <linux/bitfield.h>
> +#include <linux/clk-provider.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/rtc.h>
> +
> +/* Register map */
> +/* Config registers */
> +#define MAX31329_STATUS_REG 0x00
> +#define MAX31329_STATUS_A1F BIT(0)
> +#define MAX31329_STATUS_OSF BIT(6)
> +#define MAX31329_INT_EN_REG 0x01
> +#define MAX31329_INT_EN_A1IE BIT(0)
> +#define MAX31329_RTC_RESET_REG 0x02
> +#define MAX31329_RTC_CONFIG1_REG 0x03
> +#define MAX31329_RTC_CONFIG2_REG 0x04
> +#define MAX31329_RTC_CONFIG2_ENCLKIN BIT(2)
> +#define MAX31329_RTC_CONFIG2_ENCLKO BIT(7)
> +#define MAX31329_RTC_CFG2_CLKOHZ_MSK GENMASK(6, 5)
> +#define MAX31329_TIMER_CONFIG_REG 0x05
> +
> +/* Watch registers */
> +#define MAX31329_SECONDS_REG 0x06
> +#define MAX31329_MINUTES_REG 0x07
> +#define MAX31329_HOURS_REG 0x08
> +#define MAX31329_HOURS_F24_12 BIT(6)
> +#define MAX31329_HOURS_AM_PM BIT(5)
> +#define MAX31329_DAY_REG 0x09
> +#define MAX31329_DATE_REG 0x0A
> +#define MAX31329_MONTH_REG 0x0B
> +#define MAX31329_MONTH_CENTURY BIT(7)
> +#define MAX31329_YEAR_REG 0x0C
> +#define MAX31329_WATCH_SEC_LEN 0x07
> +#define REG_TO_OFFSET(_REG) ((_REG) - MAX31329_SECONDS_REG)
> +
> +/* Alarm registers */
> +#define MAX31329_ALM1_SEC_REG 0x0D
> +#define MAX31329_ALM1_MIN_REG 0x0E
> +#define MAX31329_ALM1_HRS_REG 0x0F
> +#define MAX31329_ALM1_DAY_DATE_REG 0x10
> +#define MAX31329_ALM1_MON_REG 0x11
> +#define MAX31329_ALM1_YEAR_REG 0x12
> +#define MAX31329_ALM1_SEC_LEN 0x06
> +
> +#define MAX31329_PWR_MGMT_REG 0x18
> +#define MAX31329_TRICKLE_REG 0x19
> +#define MAX31329_TRICKLE_EN BIT(7)
> +#define MAX31329_TRICKLE_DIODE_EN BIT(2)
> +#define MAX31329_D_TRICKLE_OHMS GENMASK(3, 0)
> +
> +/* Ram registers */
> +#define MAX31329_RAM0_START_REG 0x22
> +#define MAX31329_RAM0_END_REG 0x61
> +
> +struct max31329_data {
> + struct regmap *regmap;
> + struct rtc_device *rtc;
> + int irq;
> +#ifdef CONFIG_COMMON_CLK
> + struct clk_hw clkout_hw;
> +#endif
> +};
> +
> +/* resistance in kohms */
> +static u32 max31329_trickle_ohms[] = {
> + 3000,
> + 6000,
> + 11000
> +};
> +
> +static const struct regmap_config config = {
> + .reg_bits = 8,
> + .val_bits = 8,
> + .max_register = MAX31329_RAM0_END_REG,
> +};
> +
> +static int max31329_get_osc_status(struct device *dev)
> +{
> + struct max31329_data *max31329 = dev_get_drvdata(dev);
> + unsigned int status;
> + int ret;
> +
> + ret = regmap_read(max31329->regmap, MAX31329_STATUS_REG, &status);
> + if (ret)
> + return ret;
> +
> + if (status & MAX31329_STATUS_OSF)
> + return -EINVAL;
> +
> + return 0;
> +}
> +
> +static int max31329_alarm_irq_enable(struct device *dev, unsigned int enable)
> +{
> + struct max31329_data *max31329 = dev_get_drvdata(dev);
> +
> + return regmap_update_bits(max31329->regmap, MAX31329_INT_EN_REG,
> + MAX31329_INT_EN_A1IE,
> + enable ? MAX31329_INT_EN_A1IE : 0);
> +}
> +
> +static int max31329_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
> +{
> + struct max31329_data *max31329 = dev_get_drvdata(dev);
> + struct rtc_time *const tm = &alarm->time;
> + unsigned int aie_en, aie_flag;
> + int ret;
> + u8 regs[6];
> +
> + ret = regmap_bulk_read(max31329->regmap, MAX31329_ALM1_SEC_REG, regs,
> + MAX31329_ALM1_SEC_LEN);
> + if (ret)
> + return ret;
> +
> + ret = regmap_read(max31329->regmap, MAX31329_INT_EN_REG, &aie_en);
> + if (ret)
> + return ret;
> +
> + ret = regmap_read(max31329->regmap, MAX31329_STATUS_REG, &aie_flag);
> + if (ret)
> + return ret;
> +
> + tm->tm_sec = bcd2bin(regs[REG_TO_OFFSET(MAX31329_SECONDS_REG)] & 0x7f);
> + tm->tm_min = bcd2bin(regs[REG_TO_OFFSET(MAX31329_MINUTES_REG)] & 0x7f);
> + tm->tm_hour = bcd2bin(regs[REG_TO_OFFSET(MAX31329_HOURS_REG)] & 0x3f);
> + tm->tm_mday = bcd2bin(regs[REG_TO_OFFSET(MAX31329_DATE_REG) - 1] & 0x3f);
> + tm->tm_mon = bcd2bin(regs[REG_TO_OFFSET(MAX31329_MONTH_REG) - 1] &
> + 0x1f) - 1;
> + tm->tm_year = bcd2bin(regs[REG_TO_OFFSET(MAX31329_YEAR_REG) - 1]) + 200;
> +
> + alarm->enabled = FIELD_GET(MAX31329_INT_EN_A1IE, aie_en);
> + alarm->pending = FIELD_GET(MAX31329_STATUS_A1F, aie_flag) &&
> + alarm->enabled;
> +
> + return 0;
> +}
> +
> +static int max31329_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
> +{
> + struct max31329_data *max31329 = dev_get_drvdata(dev);
> + const struct rtc_time *tm = &alrm->time;
> + u8 regs[6], year;
> + int ret;
> +
> + regs[REG_TO_OFFSET(MAX31329_SECONDS_REG)] = bin2bcd(tm->tm_sec) & 0x7F;
> + regs[REG_TO_OFFSET(MAX31329_MINUTES_REG)] = bin2bcd(tm->tm_min) & 0x7f;
> + regs[REG_TO_OFFSET(MAX31329_HOURS_REG)] = bin2bcd(tm->tm_hour) & 0x3f;
> + regs[REG_TO_OFFSET(MAX31329_DATE_REG) - 1] = bin2bcd(tm->tm_mday) & 0x3f;
> + regs[REG_TO_OFFSET(MAX31329_MONTH_REG) - 1] = bin2bcd(tm->tm_mon + 1) & 0x1f;
> +
> + if (tm->tm_year >= 200)
> + return -EINVAL;
> +
> + year = bin2bcd(tm->tm_year - 100);
> + regs[REG_TO_OFFSET(MAX31329_YEAR_REG) - 1] = year;
> +
> + ret = regmap_bulk_write(max31329->regmap, MAX31329_ALM1_SEC_REG, regs,
> + MAX31329_ALM1_SEC_LEN);
> + if (ret)
> + return ret;
> +
> + return max31329_alarm_irq_enable(dev, alrm->enabled);
> +}
> +
> +static int max31329_read_time(struct device *dev, struct rtc_time *tm)
> +{
> + struct max31329_data *max31329 = dev_get_drvdata(dev);
> + u8 data[7], century = 0;
> + int ret;
> +
> + ret = max31329_get_osc_status(dev);
> + if (ret)
> + return ret;
> +
> + ret = regmap_bulk_read(max31329->regmap, MAX31329_SECONDS_REG, data,
> + sizeof(data));
> + if (ret)
> + return ret;
> +
> + tm->tm_sec = bcd2bin(data[REG_TO_OFFSET(MAX31329_SECONDS_REG)] & 0x7f);
> + tm->tm_min = bcd2bin(data[REG_TO_OFFSET(MAX31329_MINUTES_REG)] & 0x7f);
> + tm->tm_hour = bcd2bin(data[REG_TO_OFFSET(MAX31329_HOURS_REG)] & 0x3f);
> + /* Day of the week in linux range is 0~6 while 1~7 in RTC chip */
> + tm->tm_wday = bcd2bin(data[REG_TO_OFFSET(MAX31329_DAY_REG)] & 0x07) - 1;
> + tm->tm_mday = bcd2bin(data[REG_TO_OFFSET(MAX31329_DATE_REG)] & 0x3f);
> + /* linux tm_mon range:0~11, while month range is 1~12 in RTC chip */
> + tm->tm_mon = bcd2bin(data[REG_TO_OFFSET(MAX31329_MONTH_REG)] & 0x1f) - 1;
> +
> + century = data[REG_TO_OFFSET(MAX31329_MONTH_REG)] & MAX31329_MONTH_CENTURY;
> + tm->tm_year = bcd2bin(data[REG_TO_OFFSET(MAX31329_YEAR_REG)]) +
> + (century ? 200 : 100);
> +
> + return 0;
> +}
> +
> +static int max31329_set_time(struct device *dev, struct rtc_time *tm)
> +{
> + struct max31329_data *max31329 = dev_get_drvdata(dev);
> + u8 regs[7];
> +
> + regs[REG_TO_OFFSET(MAX31329_SECONDS_REG)] = bin2bcd(tm->tm_sec);
> + regs[REG_TO_OFFSET(MAX31329_MINUTES_REG)] = bin2bcd(tm->tm_min);
> + regs[REG_TO_OFFSET(MAX31329_HOURS_REG)] = bin2bcd(tm->tm_hour);
> + regs[REG_TO_OFFSET(MAX31329_DAY_REG)] = bin2bcd(tm->tm_wday + 1);
> + regs[REG_TO_OFFSET(MAX31329_DATE_REG)] = bin2bcd(tm->tm_mday);
> + regs[REG_TO_OFFSET(MAX31329_MONTH_REG)] = bin2bcd(tm->tm_mon + 1);
> +
> + if (tm->tm_year >= 200)
> + regs[REG_TO_OFFSET(MAX31329_MONTH_REG)] |= MAX31329_MONTH_CENTURY;
> + regs[REG_TO_OFFSET(MAX31329_YEAR_REG)] = bin2bcd(tm->tm_year % 100);
> +
> + return regmap_bulk_write(max31329->regmap, MAX31329_SECONDS_REG, regs,
> + MAX31329_WATCH_SEC_LEN);
> +}
> +
> +static const struct rtc_class_ops max31329_rtc_ops = {
> + .read_time = max31329_read_time,
> + .set_time = max31329_set_time,
> + .read_alarm = max31329_read_alarm,
> + .set_alarm = max31329_set_alarm,
> + .alarm_irq_enable = max31329_alarm_irq_enable,
> +};
> +
> +static irqreturn_t max31329_irq_handler(int irq, void *dev_id)
> +{
> + struct device *dev = dev_id;
> + struct max31329_data *max31329 = dev_get_drvdata(dev);
> + unsigned int flags, controls;
> + unsigned long events = 0;
> + int ret;
> +
> + ret = regmap_read(max31329->regmap, MAX31329_INT_EN_REG, &controls);
> + if (ret)
> + return IRQ_NONE;
> +
> + ret = regmap_read(max31329->regmap, MAX31329_STATUS_REG, &flags);
> + if (ret)
> + return IRQ_NONE;
> +
> + if (flags & MAX31329_STATUS_A1F) {
> + flags &= ~MAX31329_STATUS_A1F;
> + controls &= ~MAX31329_INT_EN_A1IE;
> + events = RTC_AF | RTC_IRQF;
> + }
> +
> + if (events) {
> + rtc_update_irq(max31329->rtc, 1, events);
> + regmap_write(max31329->regmap, MAX31329_STATUS_REG, flags);
> + regmap_write(max31329->regmap, MAX31329_INT_EN_REG, controls);
> + return IRQ_HANDLED;
> + }
> +
> + return IRQ_NONE;
> +}
> +
> +static void max31329_trickle_config(struct device *dev)
> +{
> + struct max31329_data *max31329 = dev_get_drvdata(dev);
> + u8 trickle_reg;
> + int ret, i;
> + u32 ohms;
> +
> + /* Configure the trickle charger. */
> + ret = device_property_read_u32(dev, "trickle-resistor-ohms", &ohms);
> + if (ret)
> + return;
> +
> + trickle_reg = MAX31329_TRICKLE_EN;
> + for (i = 1; i <= ARRAY_SIZE(max31329_trickle_ohms); i++) {
> + if (max31329_trickle_ohms[i - 1] == ohms) {
> + trickle_reg |= i;
> + regmap_write(max31329->regmap, MAX31329_TRICKLE_REG,
> + trickle_reg);
> + }
> + }
> +}
> +
> +static int max31329_nvram_write(void *priv, unsigned int offset, void *val,
> + size_t bytes)
> +{
> + struct regmap *max31329_regmap = (struct regmap *)priv;
> +
> + return regmap_bulk_write(max31329_regmap,
> + MAX31329_RAM0_START_REG + offset,
> + val, bytes);
> +}
> +
> +static int max31329_nvram_read(void *priv, unsigned int offset, void *val,
> + size_t bytes)
> +{
> + struct regmap *max31329_regmap = (struct regmap *)priv;
> +
> + return regmap_bulk_read(max31329_regmap,
> + MAX31329_RAM0_START_REG + offset,
> + val, bytes);
> +}
> +
> +#ifdef CONFIG_COMMON_CLK
> +#define clkout_hw_to_max31329(hw) container_of(hw, struct max31329_data, clkout_hw)
> +
> +static int clkout_rates[] = {
> + 1,
> + 4096,
> + 8192,
> + 32768
> +};
> +
> +static unsigned long max31329_clkout_recalc_rate(struct clk_hw *hw,
> + unsigned long parent_rate)
> +{
> + struct max31329_data *max31329 = clkout_hw_to_max31329(hw);
> + int clkout, ret;
> +
> + ret = regmap_read(max31329->regmap, MAX31329_RTC_CONFIG2_REG, &clkout);
> + if (ret)
> + return 0;
> +
> + return clkout_rates[FIELD_GET(MAX31329_RTC_CFG2_CLKOHZ_MSK, clkout)];
> +}
> +
> +static long max31329_clkout_round_rate(struct clk_hw *hw, unsigned long rate,
> + unsigned long *prate)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
> + if (clkout_rates[i] >= rate)
> + return clkout_rates[i];
> +
> + return 0;
> +}
> +
> +static int max31329_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
> + unsigned long parent_rate)
> +{
> + struct max31329_data *max31329 = clkout_hw_to_max31329(hw);
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
> + if (rate == clkout_rates[i])
> + return regmap_update_bits(max31329->regmap,
> + MAX31329_RTC_CONFIG2_REG,
> + MAX31329_RTC_CFG2_CLKOHZ_MSK,
> + FIELD_PREP(MAX31329_RTC_CFG2_CLKOHZ_MSK,
> + i));
> + return -EINVAL;
> +}
> +
> +static int max31329_clkout_prepare(struct clk_hw *hw)
> +{
> + struct max31329_data *max31329 = clkout_hw_to_max31329(hw);
> +
> + return regmap_update_bits(max31329->regmap, MAX31329_RTC_CONFIG2_REG,
> + MAX31329_RTC_CONFIG2_ENCLKO,
> + MAX31329_RTC_CONFIG2_ENCLKO);
> +}
> +
> +static void max31329_clkout_unprepare(struct clk_hw *hw)
> +{
> + struct max31329_data *max31329 = clkout_hw_to_max31329(hw);
> +
> + regmap_update_bits(max31329->regmap, MAX31329_RTC_CONFIG2_REG,
> + MAX31329_RTC_CONFIG2_ENCLKO,
> + FIELD_PREP(MAX31329_RTC_CONFIG2_ENCLKO, 0));
> +}
> +
> +static int max31329_clkout_is_prepared(struct clk_hw *hw)
> +{
> + struct max31329_data *max31329 = clkout_hw_to_max31329(hw);
> + int clkout, ret;
> +
> + ret = regmap_read(max31329->regmap, MAX31329_RTC_CONFIG2_REG, &clkout);
> + if (ret)
> + return ret;
> +
> + return !!(clkout & MAX31329_RTC_CONFIG2_ENCLKO);
> +}
> +
> +static const struct clk_ops max31329_clkout_ops = {
> + .prepare = max31329_clkout_prepare,
> + .unprepare = max31329_clkout_unprepare,
> + .is_prepared = max31329_clkout_is_prepared,
> + .recalc_rate = max31329_clkout_recalc_rate,
> + .round_rate = max31329_clkout_round_rate,
> + .set_rate = max31329_clkout_set_rate,
> +};
> +
> +static struct clk *max31329_clkout_register_clk(struct max31329_data *max31329,
> + struct i2c_client *client)
> +{
> + struct device_node *node = client->dev.of_node;
> + struct clk_init_data init;
> + struct clk *clk;
> +
> + init.name = "max31329-clkout";
> + init.ops = &max31329_clkout_ops;
> + init.flags = 0;
> + init.parent_names = NULL;
> + init.num_parents = 0;
> + max31329->clkout_hw.init = &init;
> +
> + /* optional override of the clockname */
> + of_property_read_string(node, "clock-output-names", &init.name);
> +
> + clk = devm_clk_register(&client->dev, &max31329->clkout_hw);
> + if (!IS_ERR(clk))
> + of_clk_add_provider(node, of_clk_src_simple_get, clk);
> +
> + return clk;
> +}
> +#endif
> +
> +static int max31329_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + struct max31329_data *max31329;
> + int ret;
> + struct nvmem_config nvmem_cfg = {
> + .name = "max31329_nvram",
> + .word_size = 1,
> + .stride = 1,
> + .size = 64,
> + .type = NVMEM_TYPE_BATTERY_BACKED,
> + .reg_read = max31329_nvram_read,
> + .reg_write = max31329_nvram_write,
> + };
> +
> + max31329 = devm_kzalloc(&client->dev, sizeof(*max31329), GFP_KERNEL);
> + if (!max31329)
> + return -ENOMEM;
> +
> + max31329->regmap = devm_regmap_init_i2c(client, &config);
> + if (IS_ERR(max31329->regmap))
> + return PTR_ERR(max31329->regmap);
> +
> + dev_set_drvdata(&client->dev, max31329);
> +
> + max31329->rtc = devm_rtc_allocate_device(&client->dev);
> + if (IS_ERR(max31329->rtc))
> + return PTR_ERR(max31329->rtc);
> +
> + max31329->rtc->ops = &max31329_rtc_ops;
> + max31329->irq = client->irq;
> + max31329->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
> + max31329->rtc->range_max = RTC_TIMESTAMP_END_2199;
> +
> + if (max31329->irq) {
> + ret = devm_request_threaded_irq(&client->dev, max31329->irq,
> + NULL, max31329_irq_handler,
> + IRQF_TRIGGER_LOW | IRQF_ONESHOT,
> + "max31329", &client->dev);
> + if (ret)
> + return ret;
> + } else {
> + clear_bit(RTC_FEATURE_ALARM, max31329->rtc->features);
> + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, max31329->rtc->features);
> + }
> +
> + if (max31329->irq || device_property_read_bool(&client->dev,
> + "wakeup-source"))
> + device_init_wakeup(&client->dev, true);
> +
> + ret = devm_rtc_register_device(max31329->rtc);
> + if (ret)
> + return ret;
> +
> + max31329_trickle_config(&client->dev);
> +
> + nvmem_cfg.priv = max31329->regmap;
> + devm_rtc_nvmem_register(max31329->rtc, &nvmem_cfg);
> +
> +#ifdef CONFIG_COMMON_CLK
> + max31329_clkout_register_clk(max31329, client);
> +#endif
> +
> + return 0;
> +}
> +
> +static const __maybe_unused struct of_device_id max31329_of_match[] = {
> + { .compatible = "maxim,max31329", },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, max31329_of_match);
> +
> +static struct i2c_driver max31329_driver = {
> + .driver = {
> + .name = "rtc-max31329",
> + .of_match_table = of_match_ptr(max31329_of_match),
> + },
> + .probe = max31329_probe,
> +};
> +module_i2c_driver(max31329_driver);
> +
> +MODULE_AUTHOR("Jagath Jog J <[email protected]>");
> +MODULE_DESCRIPTION("Maxim MAX31329 RTC driver");
> +MODULE_LICENSE("GPL");
> --
> 2.17.1
>
Hello,
I have a few small comments:
On 24/09/2022 00:23:58+0530, Jagath Jog J wrote:
> +static int max31329_get_osc_status(struct device *dev)
This function should be folded in its only call site, this will reduce
the size of the code.
> +{
> + struct max31329_data *max31329 = dev_get_drvdata(dev);
> + unsigned int status;
> + int ret;
> +
> + ret = regmap_read(max31329->regmap, MAX31329_STATUS_REG, &status);
> + if (ret)
> + return ret;
> +
> + if (status & MAX31329_STATUS_OSF)
> + return -EINVAL;
> +
> + return 0;
> +}
> +
[...]
> +static int max31329_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
> +{
> + struct max31329_data *max31329 = dev_get_drvdata(dev);
> + const struct rtc_time *tm = &alrm->time;
> + u8 regs[6], year;
> + int ret;
> +
> + regs[REG_TO_OFFSET(MAX31329_SECONDS_REG)] = bin2bcd(tm->tm_sec) & 0x7F;
> + regs[REG_TO_OFFSET(MAX31329_MINUTES_REG)] = bin2bcd(tm->tm_min) & 0x7f;
> + regs[REG_TO_OFFSET(MAX31329_HOURS_REG)] = bin2bcd(tm->tm_hour) & 0x3f;
> + regs[REG_TO_OFFSET(MAX31329_DATE_REG) - 1] = bin2bcd(tm->tm_mday) & 0x3f;
> + regs[REG_TO_OFFSET(MAX31329_MONTH_REG) - 1] = bin2bcd(tm->tm_mon + 1) & 0x1f;
> +
> + if (tm->tm_year >= 200)
> + return -EINVAL;
> +
This check is unnecessary.
> + year = bin2bcd(tm->tm_year - 100);
> + regs[REG_TO_OFFSET(MAX31329_YEAR_REG) - 1] = year;
> +
> + ret = regmap_bulk_write(max31329->regmap, MAX31329_ALM1_SEC_REG, regs,
> + MAX31329_ALM1_SEC_LEN);
> + if (ret)
> + return ret;
> +
> + return max31329_alarm_irq_enable(dev, alrm->enabled);
> +}
[...]
> +static int max31329_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
> + unsigned long parent_rate)
> +{
> + struct max31329_data *max31329 = clkout_hw_to_max31329(hw);
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
> + if (rate == clkout_rates[i])
> + return regmap_update_bits(max31329->regmap,
> + MAX31329_RTC_CONFIG2_REG,
> + MAX31329_RTC_CFG2_CLKOHZ_MSK,
> + FIELD_PREP(MAX31329_RTC_CFG2_CLKOHZ_MSK,
> + i));
Doesn't that i fit on the previous line?
> + return -EINVAL;
> +}
> +
> +static int max31329_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
Doesn't that fit on one line?
> +{
> + struct max31329_data *max31329;
> + int ret;
> + struct nvmem_config nvmem_cfg = {
> + .name = "max31329_nvram",
> + .word_size = 1,
> + .stride = 1,
> + .size = 64,
> + .type = NVMEM_TYPE_BATTERY_BACKED,
> + .reg_read = max31329_nvram_read,
> + .reg_write = max31329_nvram_write,
> + };
> +
> + max31329 = devm_kzalloc(&client->dev, sizeof(*max31329), GFP_KERNEL);
> + if (!max31329)
> + return -ENOMEM;
> +
> + max31329->regmap = devm_regmap_init_i2c(client, &config);
> + if (IS_ERR(max31329->regmap))
> + return PTR_ERR(max31329->regmap);
> +
> + dev_set_drvdata(&client->dev, max31329);
> +
> + max31329->rtc = devm_rtc_allocate_device(&client->dev);
> + if (IS_ERR(max31329->rtc))
> + return PTR_ERR(max31329->rtc);
> +
> + max31329->rtc->ops = &max31329_rtc_ops;
> + max31329->irq = client->irq;
> + max31329->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
> + max31329->rtc->range_max = RTC_TIMESTAMP_END_2199;
> +
> + if (max31329->irq) {
> + ret = devm_request_threaded_irq(&client->dev, max31329->irq,
> + NULL, max31329_irq_handler,
> + IRQF_TRIGGER_LOW | IRQF_ONESHOT,
> + "max31329", &client->dev);
> + if (ret)
> + return ret;
> + } else {
> + clear_bit(RTC_FEATURE_ALARM, max31329->rtc->features);
> + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, max31329->rtc->features);
> + }
> +
> + if (max31329->irq || device_property_read_bool(&client->dev,
> + "wakeup-source"))
> + device_init_wakeup(&client->dev, true);
> +
> + ret = devm_rtc_register_device(max31329->rtc);
> + if (ret)
> + return ret;
> +
> + max31329_trickle_config(&client->dev);
> +
> + nvmem_cfg.priv = max31329->regmap;
> + devm_rtc_nvmem_register(max31329->rtc, &nvmem_cfg);
> +
> +#ifdef CONFIG_COMMON_CLK
> + max31329_clkout_register_clk(max31329, client);
> +#endif
> +
> + return 0;
> +}
> +
> +static const __maybe_unused struct of_device_id max31329_of_match[] = {
> + { .compatible = "maxim,max31329", },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, max31329_of_match);
> +
> +static struct i2c_driver max31329_driver = {
> + .driver = {
> + .name = "rtc-max31329",
> + .of_match_table = of_match_ptr(max31329_of_match),
> + },
> + .probe = max31329_probe,
> +};
> +module_i2c_driver(max31329_driver);
> +
> +MODULE_AUTHOR("Jagath Jog J <[email protected]>");
> +MODULE_DESCRIPTION("Maxim MAX31329 RTC driver");
> +MODULE_LICENSE("GPL");
> --
> 2.17.1
>
--
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com