RTC driver for MAX31335 ±2ppm Automotive Real-Time Clock with Integrated MEMS Resonator. Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx> Signed-off-by: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx> --- changes in v8: - make `nvmem_config` and `clk_init_data` static MAINTAINERS | 8 + drivers/rtc/Kconfig | 13 + drivers/rtc/Makefile | 1 + drivers/rtc/rtc-max31335.c | 706 +++++++++++++++++++++++++++++++++++++ 4 files changed, 728 insertions(+) create mode 100644 drivers/rtc/rtc-max31335.c diff --git a/MAINTAINERS b/MAINTAINERS index 97f51d5ec1cf..0b2a6f95bae7 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12986,6 +12986,14 @@ F: Documentation/devicetree/bindings/hwmon/adi,max31827.yaml F: Documentation/hwmon/max31827.rst F: drivers/hwmon/max31827.c +MAX31335 RTC DRIVER +M: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx> +L: linux-rtc@xxxxxxxxxxxxxxx +S: Supported +W: https://ez.analog.com/linux-software-drivers +F: Documentation/devicetree/bindings/rtc/adi,max31335.yaml +F: drivers/rtc/rtc-max31335.c + MAX6650 HARDWARE MONITOR AND FAN CONTROLLER DRIVER L: linux-hwmon@xxxxxxxxxxxxxxx S: Orphan diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index 3814e0845e77..6ed8cb5c3c9a 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -373,6 +373,19 @@ config RTC_DRV_MAX8997 This driver can also be built as a module. If so, the module will be called rtc-max8997. +config RTC_DRV_MAX31335 + tristate "Analog Devices MAX31335" + depends on I2C + depends on COMMON_CLK + depends on HWMON || HWMON=n + select REGMAP_I2C + help + If you say yes here you get support for the Analog Devices + MAX31335. + + This driver can also be built as a module. If so, the module + will be called rtc-max31335. + config RTC_DRV_MAX77686 tristate "Maxim MAX77686" depends on MFD_MAX77686 || MFD_MAX77620 || MFD_MAX77714 || COMPILE_TEST diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index 7b03c3abfd78..aa3f3bac8e1c 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -88,6 +88,7 @@ obj-$(CONFIG_RTC_DRV_M41T94) += rtc-m41t94.o obj-$(CONFIG_RTC_DRV_M48T35) += rtc-m48t35.o obj-$(CONFIG_RTC_DRV_M48T59) += rtc-m48t59.o obj-$(CONFIG_RTC_DRV_M48T86) += rtc-m48t86.o +obj-$(CONFIG_RTC_DRV_MAX31335) += rtc-max31335.o obj-$(CONFIG_RTC_DRV_MAX6900) += rtc-max6900.o obj-$(CONFIG_RTC_DRV_MAX6902) += rtc-max6902.o obj-$(CONFIG_RTC_DRV_MAX6916) += rtc-max6916.o diff --git a/drivers/rtc/rtc-max31335.c b/drivers/rtc/rtc-max31335.c new file mode 100644 index 000000000000..779f872215a0 --- /dev/null +++ b/drivers/rtc/rtc-max31335.c @@ -0,0 +1,706 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * RTC driver for the MAX31335 + * + * Copyright (C) 2023 Analog Devices + * + * Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx> + * + */ + +#include <asm-generic/unaligned.h> +#include <linux/bcd.h> +#include <linux/bitfield.h> +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/hwmon.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/regmap.h> +#include <linux/rtc.h> +#include <linux/util_macros.h> + +/* MAX31335 Register Map */ +#define MAX31335_STATUS1 0x00 +#define MAX31335_INT_EN1 0x01 +#define MAX31335_STATUS2 0x02 +#define MAX31335_INT_EN2 0x03 +#define MAX31335_RTC_RESET 0x04 +#define MAX31335_RTC_CONFIG 0x05 +#define MAX31335_RTC_CONFIG2 0x06 +#define MAX31335_TIMESTAMP_CONFIG 0x07 +#define MAX31335_TIMER_CONFIG 0x08 +#define MAX31335_SECONDS_1_128 0x09 +#define MAX31335_SECONDS 0x0A +#define MAX31335_MINUTES 0x0B +#define MAX31335_HOURS 0x0C +#define MAX31335_DAY 0x0D +#define MAX31335_DATE 0x0E +#define MAX31335_MONTH 0x0F +#define MAX31335_YEAR 0x0F +#define MAX31335_ALM1_SEC 0x11 +#define MAX31335_ALM1_MIN 0x12 +#define MAX31335_ALM1_HRS 0x13 +#define MAX31335_ALM1_DAY_DATE 0x14 +#define MAX31335_ALM1_MON 0x15 +#define MAX31335_ALM1_YEAR 0x16 +#define MAX31335_ALM2_MIN 0x17 +#define MAX31335_ALM2_HRS 0x18 +#define MAX31335_ALM2_DAY_DATE 0x19 +#define MAX31335_TIMER_COUNT 0x1A +#define MAX31335_TIMER_INIT 0x1B +#define MAX31335_PWR_MGMT 0x1C +#define MAX31335_TRICKLE_REG 0x1D +#define MAX31335_AGING_OFFSET 0x1E +#define MAX31335_TS_CONFIG 0x30 +#define MAX31335_TEMP_ALARM_HIGH_MSB 0x31 +#define MAX31335_TEMP_ALARM_HIGH_LSB 0x32 +#define MAX31335_TEMP_ALARM_LOW_MSB 0x33 +#define MAX31335_TEMP_ALARM_LOW_LSB 0x34 +#define MAX31335_TEMP_DATA_MSB 0x35 +#define MAX31335_TEMP_DATA_LSB 0x36 +#define MAX31335_TS0_SEC_1_128 0x40 +#define MAX31335_TS0_SEC 0x41 +#define MAX31335_TS0_MIN 0x42 +#define MAX31335_TS0_HOUR 0x43 +#define MAX31335_TS0_DATE 0x44 +#define MAX31335_TS0_MONTH 0x45 +#define MAX31335_TS0_YEAR 0x46 +#define MAX31335_TS0_FLAGS 0x47 +#define MAX31335_TS1_SEC_1_128 0x48 +#define MAX31335_TS1_SEC 0x49 +#define MAX31335_TS1_MIN 0x4A +#define MAX31335_TS1_HOUR 0x4B +#define MAX31335_TS1_DATE 0x4C +#define MAX31335_TS1_MONTH 0x4D +#define MAX31335_TS1_YEAR 0x4E +#define MAX31335_TS1_FLAGS 0x4F +#define MAX31335_TS2_SEC_1_128 0x50 +#define MAX31335_TS2_SEC 0x51 +#define MAX31335_TS2_MIN 0x52 +#define MAX31335_TS2_HOUR 0x53 +#define MAX31335_TS2_DATE 0x54 +#define MAX31335_TS2_MONTH 0x55 +#define MAX31335_TS2_YEAR 0x56 +#define MAX31335_TS2_FLAGS 0x57 +#define MAX31335_TS3_SEC_1_128 0x58 +#define MAX31335_TS3_SEC 0x59 +#define MAX31335_TS3_MIN 0x5A +#define MAX31335_TS3_HOUR 0x5B +#define MAX31335_TS3_DATE 0x5C +#define MAX31335_TS3_MONTH 0x5D +#define MAX31335_TS3_YEAR 0x5E +#define MAX31335_TS3_FLAGS 0x5F + +/* MAX31335_STATUS1 Bit Definitions */ +#define MAX31335_STATUS1_PSDECT BIT(7) +#define MAX31335_STATUS1_OSF BIT(6) +#define MAX31335_STATUS1_PFAIL BIT(5) +#define MAX31335_STATUS1_VBATLOW BIT(4) +#define MAX31335_STATUS1_DIF BIT(3) +#define MAX31335_STATUS1_TIF BIT(2) +#define MAX31335_STATUS1_A2F BIT(1) +#define MAX31335_STATUS1_A1F BIT(0) + +/* MAX31335_INT_EN1 Bit Definitions */ +#define MAX31335_INT_EN1_DOSF BIT(6) +#define MAX31335_INT_EN1_PFAILE BIT(5) +#define MAX31335_INT_EN1_VBATLOWE BIT(4) +#define MAX31335_INT_EN1_DIE BIT(3) +#define MAX31335_INT_EN1_TIE BIT(2) +#define MAX31335_INT_EN1_A2IE BIT(1) +#define MAX31335_INT_EN1_A1IE BIT(0) + +/* MAX31335_STATUS2 Bit Definitions */ +#define MAX31335_STATUS2_TEMP_RDY BIT(2) +#define MAX31335_STATUS2_OTF BIT(1) +#define MAX31335_STATUS2_UTF BIT(0) + +/* MAX31335_INT_EN2 Bit Definitions */ +#define MAX31335_INT_EN2_TEMP_RDY_EN BIT(2) +#define MAX31335_INT_EN2_OTIE BIT(1) +#define MAX31335_INT_EN2_UTIE BIT(0) + +/* MAX31335_RTC_RESET Bit Definitions */ +#define MAX31335_RTC_RESET_SWRST BIT(0) + +/* MAX31335_RTC_CONFIG1 Bit Definitions */ +#define MAX31335_RTC_CONFIG1_EN_IO BIT(6) +#define MAX31335_RTC_CONFIG1_A1AC GENMASK(5, 4) +#define MAX31335_RTC_CONFIG1_DIP BIT(3) +#define MAX31335_RTC_CONFIG1_I2C_TIMEOUT BIT(1) +#define MAX31335_RTC_CONFIG1_EN_OSC BIT(0) + +/* MAX31335_RTC_CONFIG2 Bit Definitions */ +#define MAX31335_RTC_CONFIG2_ENCLKO BIT(2) +#define MAX31335_RTC_CONFIG2_CLKO_HZ GENMASK(1, 0) + +/* MAX31335_TIMESTAMP_CONFIG Bit Definitions */ +#define MAX31335_TIMESTAMP_CONFIG_TSVLOW BIT(5) +#define MAX31335_TIMESTAMP_CONFIG_TSPWM BIT(4) +#define MAX31335_TIMESTAMP_CONFIG_TSDIN BIT(3) +#define MAX31335_TIMESTAMP_CONFIG_TSOW BIT(2) +#define MAX31335_TIMESTAMP_CONFIG_TSR BIT(1) +#define MAX31335_TIMESTAMP_CONFIG_TSE BIT(0) + +/* MAX31335_TIMER_CONFIG Bit Definitions */ +#define MAX31335_TIMER_CONFIG_TE BIT(4) +#define MAX31335_TIMER_CONFIG_TPAUSE BIT(3) +#define MAX31335_TIMER_CONFIG_TRPT BIT(2) +#define MAX31335_TIMER_CONFIG_TFS GENMASK(1, 0) + +/* MAX31335_HOURS Bit Definitions */ +#define MAX31335_HOURS_F_24_12 BIT(6) +#define MAX31335_HOURS_HR_20_AM_PM BIT(5) + +/* MAX31335_MONTH Bit Definitions */ +#define MAX31335_MONTH_CENTURY BIT(7) + +/* MAX31335_PWR_MGMT Bit Definitions */ +#define MAX31335_PWR_MGMT_PFVT BIT(0) + +/* MAX31335_TRICKLE_REG Bit Definitions */ +#define MAX31335_TRICKLE_REG_TRICKLE GENMASK(3, 1) +#define MAX31335_TRICKLE_REG_EN_TRICKLE BIT(0) + +/* MAX31335_TS_CONFIG Bit Definitions */ +#define MAX31335_TS_CONFIG_AUTO BIT(4) +#define MAX31335_TS_CONFIG_CONVERT_T BIT(3) +#define MAX31335_TS_CONFIG_TSINT GENMASK(2, 0) + +/* MAX31335_TS_FLAGS Bit Definitions */ +#define MAX31335_TS_FLAGS_VLOWF BIT(3) +#define MAX31335_TS_FLAGS_VBATF BIT(2) +#define MAX31335_TS_FLAGS_VCCF BIT(1) +#define MAX31335_TS_FLAGS_DINF BIT(0) + +/* MAX31335 Miscellaneous Definitions */ +#define MAX31335_TRICKLE_SCHOTTKY_DIODE 1 +#define MAX31335_TRICKLE_STANDARD_DIODE 4 +#define MAX31335_RAM_SIZE 32 +#define MAX31335_TIME_SIZE 0x07 + +#define clk_hw_to_max31335(_hw) container_of(_hw, struct max31335_data, clkout) + +struct max31335_data { + struct regmap *regmap; + struct rtc_device *rtc; + struct clk_hw clkout; +}; + +static const int max31335_clkout_freq[] = { 1, 64, 1024, 32768 }; + +static const u16 max31335_trickle_resistors[] = {3000, 6000, 11000}; + +static bool max31335_volatile_reg(struct device *dev, unsigned int reg) +{ + /* time keeping registers */ + if (reg >= MAX31335_SECONDS && + reg < MAX31335_SECONDS + MAX31335_TIME_SIZE) + return true; + + /* interrupt status register */ + if (reg == MAX31335_INT_EN1_A1IE) + return true; + + /* temperature registers */ + if (reg == MAX31335_TEMP_DATA_MSB || MAX31335_TEMP_DATA_LSB) + return true; + + return false; +} + +static const struct regmap_config regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = 0x5F, + .volatile_reg = max31335_volatile_reg, +}; + +static int max31335_read_time(struct device *dev, struct rtc_time *tm) +{ + struct max31335_data *max31335 = dev_get_drvdata(dev); + u8 date[7]; + int ret; + + ret = regmap_bulk_read(max31335->regmap, MAX31335_SECONDS, date, + sizeof(date)); + if (ret) + return ret; + + tm->tm_sec = bcd2bin(date[0] & 0x7f); + tm->tm_min = bcd2bin(date[1] & 0x7f); + tm->tm_hour = bcd2bin(date[2] & 0x3f); + tm->tm_wday = bcd2bin(date[3] & 0x7) - 1; + tm->tm_mday = bcd2bin(date[4] & 0x3f); + tm->tm_mon = bcd2bin(date[5] & 0x1f) - 1; + tm->tm_year = bcd2bin(date[6]) + 100; + + if (FIELD_GET(MAX31335_MONTH_CENTURY, date[5])) + tm->tm_year += 100; + + return 0; +} + +static int max31335_set_time(struct device *dev, struct rtc_time *tm) +{ + struct max31335_data *max31335 = dev_get_drvdata(dev); + u8 date[7]; + + date[0] = bin2bcd(tm->tm_sec); + date[1] = bin2bcd(tm->tm_min); + date[2] = bin2bcd(tm->tm_hour); + date[3] = bin2bcd(tm->tm_wday + 1); + date[4] = bin2bcd(tm->tm_mday); + date[5] = bin2bcd(tm->tm_mon + 1); + date[6] = bin2bcd(tm->tm_year % 100); + + if (tm->tm_year >= 200) + date[5] |= FIELD_PREP(MAX31335_MONTH_CENTURY, 1); + + return regmap_bulk_write(max31335->regmap, MAX31335_SECONDS, date, + sizeof(date)); +} + +static int max31335_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct max31335_data *max31335 = dev_get_drvdata(dev); + int ret, ctrl, status; + struct rtc_time time; + u8 regs[6]; + + ret = regmap_bulk_read(max31335->regmap, MAX31335_ALM1_SEC, regs, + sizeof(regs)); + if (ret) + return ret; + + alrm->time.tm_sec = bcd2bin(regs[0] & 0x7f); + alrm->time.tm_min = bcd2bin(regs[1] & 0x7f); + alrm->time.tm_hour = bcd2bin(regs[2] & 0x3f); + alrm->time.tm_mday = bcd2bin(regs[3] & 0x3f); + alrm->time.tm_mon = bcd2bin(regs[4] & 0x1f) - 1; + alrm->time.tm_year = bcd2bin(regs[5]) + 100; + + ret = max31335_read_time(dev, &time); + if (ret) + return ret; + + if (time.tm_year >= 200) + alrm->time.tm_year += 100; + + ret = regmap_read(max31335->regmap, MAX31335_INT_EN1, &ctrl); + if (ret) + return ret; + + ret = regmap_read(max31335->regmap, MAX31335_STATUS1, &status); + if (ret) + return ret; + + alrm->enabled = FIELD_GET(MAX31335_INT_EN1_A1IE, ctrl); + alrm->pending = FIELD_GET(MAX31335_STATUS1_A1F, status); + + return 0; +} + +static int max31335_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct max31335_data *max31335 = dev_get_drvdata(dev); + unsigned int reg; + u8 regs[6]; + int ret; + + regs[0] = bin2bcd(alrm->time.tm_sec); + regs[1] = bin2bcd(alrm->time.tm_min); + regs[2] = bin2bcd(alrm->time.tm_hour); + regs[3] = bin2bcd(alrm->time.tm_mday); + regs[4] = bin2bcd(alrm->time.tm_mon + 1); + regs[5] = bin2bcd(alrm->time.tm_year % 100); + + ret = regmap_bulk_write(max31335->regmap, MAX31335_ALM1_SEC, + regs, sizeof(regs)); + if (ret) + return ret; + + reg = FIELD_PREP(MAX31335_INT_EN1_A1IE, alrm->enabled); + ret = regmap_update_bits(max31335->regmap, MAX31335_INT_EN1, + MAX31335_INT_EN1_A1IE, reg); + if (ret) + return ret; + + ret = regmap_update_bits(max31335->regmap, MAX31335_STATUS1, + MAX31335_STATUS1_A1F, 0); + + return 0; +} + +static int max31335_alarm_irq_enable(struct device *dev, unsigned int enabled) +{ + struct max31335_data *max31335 = dev_get_drvdata(dev); + + return regmap_update_bits(max31335->regmap, MAX31335_INT_EN1, + MAX31335_INT_EN1_A1IE, enabled); +} + +static irqreturn_t max31335_handle_irq(int irq, void *dev_id) +{ + struct max31335_data *max31335 = dev_id; + struct mutex *lock = &max31335->rtc->ops_lock; + int ret, status; + + mutex_lock(lock); + + ret = regmap_read(max31335->regmap, MAX31335_STATUS1, &status); + if (ret) + goto exit; + + if (FIELD_GET(MAX31335_STATUS1_A1F, status)) { + ret = regmap_update_bits(max31335->regmap, MAX31335_STATUS1, + MAX31335_STATUS1_A1F, 0); + if (ret) + goto exit; + + rtc_update_irq(max31335->rtc, 1, RTC_AF | RTC_IRQF); + } + +exit: + mutex_unlock(lock); + + return IRQ_HANDLED; +} + +static const struct rtc_class_ops max31335_rtc_ops = { + .read_time = max31335_read_time, + .set_time = max31335_set_time, + .read_alarm = max31335_read_alarm, + .set_alarm = max31335_set_alarm, + .alarm_irq_enable = max31335_alarm_irq_enable, +}; + +static int max31335_trickle_charger_setup(struct device *dev, + struct max31335_data *max31335) +{ + u32 ohms, chargeable; + int i, trickle_cfg; + const char *diode; + + if (device_property_read_u32(dev, "aux-voltage-chargeable", + &chargeable)) + return 0; + + if (device_property_read_u32(dev, "trickle-resistor-ohms", &ohms)) + return 0; + + if (device_property_read_string(dev, "adi,tc-diode", &diode)) + return 0; + + if (!strcmp(diode, "schottky")) + trickle_cfg = MAX31335_TRICKLE_SCHOTTKY_DIODE; + else if (!strcmp(diode, "standard+schottky")) + trickle_cfg = MAX31335_TRICKLE_STANDARD_DIODE; + else + dev_err_probe(dev, -EINVAL, "Invalid tc-diode value: %s\n", + diode); + + for (i = 0; i < ARRAY_SIZE(max31335_trickle_resistors); i++) + if (ohms == max31335_trickle_resistors[i]) + break; + + if (i >= ARRAY_SIZE(max31335_trickle_resistors)) + return 0; + + i = i + trickle_cfg; + + return regmap_write(max31335->regmap, MAX31335_TRICKLE_REG, + FIELD_PREP(MAX31335_TRICKLE_REG_TRICKLE, i) | + FIELD_PREP(MAX31335_TRICKLE_REG_EN_TRICKLE, + chargeable)); +} + +static unsigned long max31335_clkout_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct max31335_data *max31335 = clk_hw_to_max31335(hw); + unsigned int freq_mask; + unsigned int reg; + int ret; + + ret = regmap_read(max31335->regmap, MAX31335_RTC_CONFIG2, ®); + if (ret) + return 0; + + freq_mask = __roundup_pow_of_two(ARRAY_SIZE(max31335_clkout_freq)) - 1; + + return max31335_clkout_freq[reg & freq_mask]; +} + +static long max31335_clkout_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + int index; + + index = find_closest(rate, max31335_clkout_freq, + ARRAY_SIZE(max31335_clkout_freq)); + + return max31335_clkout_freq[index]; +} + +static int max31335_clkout_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct max31335_data *max31335 = clk_hw_to_max31335(hw); + unsigned int freq_mask; + int index; + + index = find_closest(rate, max31335_clkout_freq, + ARRAY_SIZE(max31335_clkout_freq)); + freq_mask = __roundup_pow_of_two(ARRAY_SIZE(max31335_clkout_freq)) - 1; + + return regmap_update_bits(max31335->regmap, MAX31335_RTC_CONFIG2, + freq_mask, index); +} + +static int max31335_clkout_enable(struct clk_hw *hw) +{ + struct max31335_data *max31335 = clk_hw_to_max31335(hw); + + return regmap_set_bits(max31335->regmap, MAX31335_RTC_CONFIG2, + MAX31335_RTC_CONFIG2_ENCLKO); +} + +static void max31335_clkout_disable(struct clk_hw *hw) +{ + struct max31335_data *max31335 = clk_hw_to_max31335(hw); + + regmap_clear_bits(max31335->regmap, MAX31335_RTC_CONFIG2, + MAX31335_RTC_CONFIG2_ENCLKO); +} + +static int max31335_clkout_is_enabled(struct clk_hw *hw) +{ + struct max31335_data *max31335 = clk_hw_to_max31335(hw); + unsigned int reg; + int ret; + + ret = regmap_read(max31335->regmap, MAX31335_RTC_CONFIG2, ®); + if (ret) + return ret; + + return !!(reg & MAX31335_RTC_CONFIG2_ENCLKO); +} + +static const struct clk_ops max31335_clkout_ops = { + .recalc_rate = max31335_clkout_recalc_rate, + .round_rate = max31335_clkout_round_rate, + .set_rate = max31335_clkout_set_rate, + .enable = max31335_clkout_enable, + .disable = max31335_clkout_disable, + .is_enabled = max31335_clkout_is_enabled, +}; + +static struct clk_init_data max31335_clk_init = { + .name = "max31335-clkout", + .ops = &max31335_clkout_ops, +}; + +static int max31335_nvmem_reg_read(void *priv, unsigned int offset, + void *val, size_t bytes) +{ + struct max31335_data *max31335 = priv; + unsigned int reg = MAX31335_TS0_SEC_1_128 + offset; + + return regmap_bulk_read(max31335->regmap, reg, val, bytes); +} + +static int max31335_nvmem_reg_write(void *priv, unsigned int offset, + void *val, size_t bytes) +{ + struct max31335_data *max31335 = priv; + unsigned int reg = MAX31335_TS0_SEC_1_128 + offset; + + return regmap_bulk_write(max31335->regmap, reg, val, bytes); +} + +static struct nvmem_config max31335_nvmem_cfg = { + .reg_read = max31335_nvmem_reg_read, + .reg_write = max31335_nvmem_reg_write, + .word_size = 8, + .size = MAX31335_RAM_SIZE, +}; + +#if IS_REACHABLE(HWMON) +static int max31335_read_temp(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + struct max31335_data *max31335 = dev_get_drvdata(dev); + u8 reg[2]; + s16 temp; + int ret; + + if (type != hwmon_temp || attr != hwmon_temp_input) + return -EOPNOTSUPP; + + ret = regmap_bulk_read(max31335->regmap, MAX31335_TEMP_DATA_MSB, + reg, 2); + if (ret) + return ret; + + temp = get_unaligned_be16(reg); + + *val = (temp / 64) * 250; + + return 0; +} + +static umode_t max31335_is_visible(const void *data, + enum hwmon_sensor_types type, + u32 attr, int channel) +{ + if (type == hwmon_temp && attr == hwmon_temp_input) + return 0444; + + return 0; +} + +static const struct hwmon_channel_info *max31335_info[] = { + HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT), + NULL +}; + +static const struct hwmon_ops max31335_hwmon_ops = { + .is_visible = max31335_is_visible, + .read = max31335_read_temp, +}; + +static const struct hwmon_chip_info max31335_chip_info = { + .ops = &max31335_hwmon_ops, + .info = max31335_info, +}; +#endif + +static int max31335_clkout_register(struct device *dev) +{ + struct max31335_data *max31335 = dev_get_drvdata(dev); + int ret; + + if (!device_property_present(dev, "#clock-cells")) + return regmap_clear_bits(max31335->regmap, MAX31335_RTC_CONFIG2, + MAX31335_RTC_CONFIG2_ENCLKO); + + max31335->clkout.init = &max31335_clk_init; + + ret = devm_clk_hw_register(dev, &max31335->clkout); + if (ret) + return dev_err_probe(dev, ret, "cannot register clock\n"); + + ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get, + &max31335->clkout); + if (ret) + return dev_err_probe(dev, ret, "cannot add hw provider\n"); + + max31335->clkout.clk = devm_clk_get_enabled(dev, NULL); + if (IS_ERR(max31335->clkout.clk)) + return dev_err_probe(dev, PTR_ERR(max31335->clkout.clk), + "cannot enable clkout\n"); + + return 0; +} + +static int max31335_probe(struct i2c_client *client) +{ + struct max31335_data *max31335; +#if IS_REACHABLE(HWMON) + struct device *hwmon; +#endif + int ret; + + max31335 = devm_kzalloc(&client->dev, sizeof(*max31335), GFP_KERNEL); + if (!max31335) + return -ENOMEM; + + max31335->regmap = devm_regmap_init_i2c(client, ®map_config); + if (IS_ERR(max31335->regmap)) + return PTR_ERR(max31335->regmap); + + i2c_set_clientdata(client, max31335); + + max31335->rtc = devm_rtc_allocate_device(&client->dev); + if (IS_ERR(max31335->rtc)) + return PTR_ERR(max31335->rtc); + + max31335->rtc->ops = &max31335_rtc_ops; + max31335->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; + max31335->rtc->range_max = RTC_TIMESTAMP_END_2199; + max31335->rtc->alarm_offset_max = 24 * 60 * 60; + + ret = max31335_clkout_register(&client->dev); + if (ret) + return ret; + + if (client->irq > 0) { + ret = devm_request_threaded_irq(&client->dev, client->irq, + NULL, max31335_handle_irq, + IRQF_ONESHOT, + "max31335", max31335); + if (ret) { + dev_warn(&client->dev, + "unable to request IRQ, alarm max31335 disabled\n"); + client->irq = 0; + } + } + + if (!client->irq) + clear_bit(RTC_FEATURE_ALARM, max31335->rtc->features); + + max31335_nvmem_cfg.priv = max31335; + ret = devm_rtc_nvmem_register(max31335->rtc, &max31335_nvmem_cfg); + if (ret) + dev_err_probe(&client->dev, ret, "cannot register rtc nvmem\n"); + +#if IS_REACHABLE(HWMON) + hwmon = devm_hwmon_device_register_with_info(&client->dev, client->name, + max31335, + &max31335_chip_info, + NULL); + if (IS_ERR(hwmon)) + dev_err_probe(&client->dev, PTR_ERR(hwmon), + "cannot register hwmon device\n"); +#endif + + ret = max31335_trickle_charger_setup(&client->dev, max31335); + if (ret) + return ret; + + return devm_rtc_register_device(max31335->rtc); +} + +static const struct i2c_device_id max31335_id[] = { + { "max31335", 0 }, + { } +}; + +MODULE_DEVICE_TABLE(i2c, max31335_id); + +static const struct of_device_id max31335_of_match[] = { + { .compatible = "adi,max31335" }, + { } +}; + +MODULE_DEVICE_TABLE(of, max31335_of_match); + +static struct i2c_driver max31335_driver = { + .driver = { + .name = "rtc-max31335", + .of_match_table = max31335_of_match, + }, + .probe = max31335_probe, + .id_table = max31335_id, +}; +module_i2c_driver(max31335_driver); + +MODULE_AUTHOR("Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx>"); +MODULE_DESCRIPTION("MAX31335 RTC driver"); +MODULE_LICENSE("GPL"); -- 2.42.0
