Re: [PATCH v2 2/4] hwmon: (adt7470) Convert to use regmap

Guenter Roeck
2021-08-27T21:17:50Z

On Thu, Aug 26, 2021 at 02:41:19PM +1200, Chris Packham wrote:
> Convert the adt7470 to using regmap which allows better error handling.
>
> Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>

Applied.

Thanks,
Guenter

> ---
> Change in v2:
> - split regmap and devm_hwmon_device_register_with_info into separate
> patches to aid review
>
> drivers/hwmon/adt7470.c | 430 +++++++++++++++++++++++-----------------
> 1 file changed, 249 insertions(+), 181 deletions(-)
>
> diff --git a/drivers/hwmon/adt7470.c b/drivers/hwmon/adt7470.c
> index 3358ec58b977..ad3e46667be8 100644
> --- a/drivers/hwmon/adt7470.c
> +++ b/drivers/hwmon/adt7470.c
> @@ -18,6 +18,7 @@
> #include <linux/delay.h>
> #include <linux/log2.h>
> #include <linux/kthread.h>
> +#include <linux/regmap.h>
> #include <linux/slab.h>
> #include <linux/util_macros.h>
>
> @@ -35,7 +36,10 @@ static const unsigned short normal_i2c[] = { 0x2C, 0x2E, 0x2F, I2C_CLIENT_END };
> #define ADT7470_REG_PWM_MAX_BASE_ADDR 0x38
> #define ADT7470_REG_PWM_MAX_MAX_ADDR 0x3B
> #define ADT7470_REG_CFG 0x40
> +#define ADT7470_STRT_MASK 0x01
> +#define ADT7470_TEST_MASK 0x02
> #define ADT7470_FSPD_MASK 0x04
> +#define ADT7470_T05_STB_MASK 0x80
> #define ADT7470_REG_ALARM1 0x41
> #define ADT7470_R1T_ALARM 0x01
> #define ADT7470_R2T_ALARM 0x02
> @@ -137,7 +141,7 @@ static const unsigned short normal_i2c[] = { 0x2C, 0x2E, 0x2F, I2C_CLIENT_END };
> #define ADT7470_FREQ_SHIFT 4
>
> struct adt7470_data {
> - struct i2c_client *client;
> + struct regmap *regmap;
> struct mutex lock;
> char sensors_valid;
> char limits_valid;
> @@ -171,52 +175,76 @@ struct adt7470_data {
> * 16-bit registers on the ADT7470 are low-byte first. The data sheet says
> * that the low byte must be read before the high byte.
> */
> -static inline int adt7470_read_word_data(struct i2c_client *client, u8 reg)
> +static inline int adt7470_read_word_data(struct adt7470_data *data, unsigned int reg,
> + unsigned int *val)
> {
> - u16 foo;
> + u8 regval[2];
> + int err;
>
> - foo = i2c_smbus_read_byte_data(client, reg);
> - foo |= ((u16)i2c_smbus_read_byte_data(client, reg + 1) << 8);
> - return foo;
> + err = regmap_bulk_read(data->regmap, reg, &regval, 2);
> + if (err < 0)
> + return err;
> +
> + *val = regval[0] | (regval[1] << 8);
> +
> + return 0;
> }
>
> -static inline int adt7470_write_word_data(struct i2c_client *client, u8 reg,
> - u16 value)
> +static inline int adt7470_write_word_data(struct adt7470_data *data, unsigned int reg,
> + unsigned int val)
> {
> - return i2c_smbus_write_byte_data(client, reg, value & 0xFF)
> - || i2c_smbus_write_byte_data(client, reg + 1, value >> 8);
> + u8 regval[2];
> +
> + regval[0] = val & 0xFF;
> + regval[1] = val >> 8;
> +
> + return regmap_bulk_write(data->regmap, reg, &regval, 2);
> }
>
> /* Probe for temperature sensors. Assumes lock is held */
> -static int adt7470_read_temperatures(struct i2c_client *client,
> - struct adt7470_data *data)
> +static int adt7470_read_temperatures(struct adt7470_data *data)
> {
> unsigned long res;
> + unsigned int pwm_cfg[2];
> + int err;
> int i;
> - u8 cfg, pwm[4], pwm_cfg[2];
> + u8 pwm[ADT7470_FAN_COUNT];
>
> /* save pwm[1-4] config register */
> - pwm_cfg[0] = i2c_smbus_read_byte_data(client, ADT7470_REG_PWM_CFG(0));
> - pwm_cfg[1] = i2c_smbus_read_byte_data(client, ADT7470_REG_PWM_CFG(2));
> + err = regmap_read(data->regmap, ADT7470_REG_PWM_CFG(0), &pwm_cfg[0]);
> + if (err < 0)
> + return err;
> + err = regmap_read(data->regmap, ADT7470_REG_PWM_CFG(2), &pwm_cfg[1]);
> + if (err < 0)
> + return err;
>
> /* set manual pwm to whatever it is set to now */
> - for (i = 0; i < ADT7470_FAN_COUNT; i++)
> - pwm[i] = i2c_smbus_read_byte_data(client, ADT7470_REG_PWM(i));
> + err = regmap_bulk_read(data->regmap, ADT7470_REG_PWM(0), &pwm[0],
> + ADT7470_PWM_COUNT);
> + if (err < 0)
> + return err;
>
> /* put pwm in manual mode */
> - i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_CFG(0),
> - pwm_cfg[0] & ~(ADT7470_PWM_AUTO_MASK));
> - i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_CFG(2),
> - pwm_cfg[1] & ~(ADT7470_PWM_AUTO_MASK));
> + err = regmap_update_bits(data->regmap, ADT7470_REG_PWM_CFG(0),
> + ADT7470_PWM_AUTO_MASK, 0);
> + if (err < 0)
> + return err;
> + err = regmap_update_bits(data->regmap, ADT7470_REG_PWM_CFG(2),
> + ADT7470_PWM_AUTO_MASK, 0);
> + if (err < 0)
> + return err;
>
> /* write pwm control to whatever it was */
> - for (i = 0; i < ADT7470_FAN_COUNT; i++)
> - i2c_smbus_write_byte_data(client, ADT7470_REG_PWM(i), pwm[i]);
> + err = regmap_bulk_write(data->regmap, ADT7470_REG_PWM(0), &pwm[0],
> + ADT7470_PWM_COUNT);
> + if (err < 0)
> + return err;
>
> /* start reading temperature sensors */
> - cfg = i2c_smbus_read_byte_data(client, ADT7470_REG_CFG);
> - cfg |= 0x80;
> - i2c_smbus_write_byte_data(client, ADT7470_REG_CFG, cfg);
> + err = regmap_update_bits(data->regmap, ADT7470_REG_CFG,
> + ADT7470_T05_STB_MASK, ADT7470_T05_STB_MASK);
> + if (err < 0)
> + return err;
>
> /* Delay is 200ms * number of temp sensors. */
> res = msleep_interruptible((data->num_temp_sensors >= 0 ?
> @@ -224,26 +252,31 @@ static int adt7470_read_temperatures(struct i2c_client *client,
> TEMP_COLLECTION_TIME));
>
> /* done reading temperature sensors */
> - cfg = i2c_smbus_read_byte_data(client, ADT7470_REG_CFG);
> - cfg &= ~0x80;
> - i2c_smbus_write_byte_data(client, ADT7470_REG_CFG, cfg);
> + err = regmap_update_bits(data->regmap, ADT7470_REG_CFG,
> + ADT7470_T05_STB_MASK, 0);
> + if (err < 0)
> + return err;
>
> /* restore pwm[1-4] config registers */
> - i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_CFG(0), pwm_cfg[0]);
> - i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_CFG(2), pwm_cfg[1]);
> + err = regmap_write(data->regmap, ADT7470_REG_PWM_CFG(0), pwm_cfg[0]);
> + if (err < 0)
> + return err;
> + err = regmap_write(data->regmap, ADT7470_REG_PWM_CFG(2), pwm_cfg[1]);
> + if (err < 0)
> + return err;
>
> - if (res) {
> - pr_err("ha ha, interrupted\n");
> + if (res)
> return -EAGAIN;
> - }
>
> /* Only count fans if we have to */
> if (data->num_temp_sensors >= 0)
> return 0;
>
> + err = regmap_bulk_read(data->regmap, ADT7470_TEMP_REG(0), &data->temp[0],
> + ADT7470_TEMP_COUNT);
> + if (err < 0)
> + return err;
> for (i = 0; i < ADT7470_TEMP_COUNT; i++) {
> - data->temp[i] = i2c_smbus_read_byte_data(client,
> - ADT7470_TEMP_REG(i));
> if (data->temp[i])
> data->num_temp_sensors = i + 1;
> }
> @@ -258,7 +291,7 @@ static int adt7470_update_thread(void *p)
>
> while (!kthread_should_stop()) {
> mutex_lock(&data->lock);
> - adt7470_read_temperatures(client, data);
> + adt7470_read_temperatures(data);
> mutex_unlock(&data->lock);
>
> set_current_state(TASK_INTERRUPTIBLE);
> @@ -273,89 +306,116 @@ static int adt7470_update_thread(void *p)
>
> static int adt7470_update_sensors(struct adt7470_data *data)
> {
> - struct i2c_client *client = data->client;
> - u8 cfg;
> + unsigned int val;
> + int err;
> int i;
>
> if (!data->temperatures_probed)
> - adt7470_read_temperatures(client, data);
> + err = adt7470_read_temperatures(data);
> else
> - for (i = 0; i < ADT7470_TEMP_COUNT; i++)
> - data->temp[i] = i2c_smbus_read_byte_data(client,
> - ADT7470_TEMP_REG(i));
> + err = regmap_bulk_read(data->regmap, ADT7470_TEMP_REG(0), &data->temp[0],
> + ADT7470_TEMP_COUNT);
> + if (err < 0)
> + return err;
>
> - for (i = 0; i < ADT7470_FAN_COUNT; i++)
> - data->fan[i] = adt7470_read_word_data(client,
> - ADT7470_REG_FAN(i));
> -
> - for (i = 0; i < ADT7470_PWM_COUNT; i++) {
> - int reg;
> - int reg_mask;
> -
> - data->pwm[i] = i2c_smbus_read_byte_data(client,
> - ADT7470_REG_PWM(i));
> -
> - if (i % 2)
> - reg_mask = ADT7470_PWM2_AUTO_MASK;
> - else
> - reg_mask = ADT7470_PWM1_AUTO_MASK;
> -
> - reg = ADT7470_REG_PWM_CFG(i);
> - if (i2c_smbus_read_byte_data(client, reg) & reg_mask)
> - data->pwm_automatic[i] = 1;
> - else
> - data->pwm_automatic[i] = 0;
> -
> - reg = ADT7470_REG_PWM_AUTO_TEMP(i);
> - cfg = i2c_smbus_read_byte_data(client, reg);
> - if (!(i % 2))
> - data->pwm_auto_temp[i] = cfg >> 4;
> - else
> - data->pwm_auto_temp[i] = cfg & 0xF;
> + for (i = 0; i < ADT7470_FAN_COUNT; i++) {
> + err = adt7470_read_word_data(data, ADT7470_REG_FAN(i), &val);
> + if (err < 0)
> + return err;
> + data->fan[i] = val;
> }
>
> - if (i2c_smbus_read_byte_data(client, ADT7470_REG_CFG) &
> - ADT7470_FSPD_MASK)
> - data->force_pwm_max = 1;
> - else
> - data->force_pwm_max = 0;
> + err = regmap_bulk_read(data->regmap, ADT7470_REG_PWM(0), &data->pwm[0], ADT7470_PWM_COUNT);
> + if (err < 0)
> + return err;
>
> - data->alarm = i2c_smbus_read_byte_data(client, ADT7470_REG_ALARM1);
> - if (data->alarm & ADT7470_OOL_ALARM)
> - data->alarm |= ALARM2(i2c_smbus_read_byte_data(client,
> - ADT7470_REG_ALARM2));
> - data->alarms_mask = adt7470_read_word_data(client,
> - ADT7470_REG_ALARM1_MASK);
> + for (i = 0; i < ADT7470_PWM_COUNT; i++) {
> + unsigned int mask;
> +
> + if (i % 2)
> + mask = ADT7470_PWM2_AUTO_MASK;
> + else
> + mask = ADT7470_PWM1_AUTO_MASK;
> +
> + err = regmap_read(data->regmap, ADT7470_REG_PWM_CFG(i), &val);
> + if (err < 0)
> + return err;
> + data->pwm_automatic[i] = !!(val & mask);
> +
> + err = regmap_read(data->regmap, ADT7470_REG_PWM_AUTO_TEMP(i), &val);
> + if (err < 0)
> + return err;
> + if (!(i % 2))
> + data->pwm_auto_temp[i] = val >> 4;
> + else
> + data->pwm_auto_temp[i] = val & 0xF;
> + }
> +
> + err = regmap_read(data->regmap, ADT7470_REG_CFG, &val);
> + if (err < 0)
> + return err;
> + data->force_pwm_max = !!(val & ADT7470_FSPD_MASK);
> +
> + err = regmap_read(data->regmap, ADT7470_REG_ALARM1, &val);
> + if (err < 0)
> + return err;
> + data->alarm = val;
> + if (data->alarm & ADT7470_OOL_ALARM) {
> + err = regmap_read(data->regmap, ADT7470_REG_ALARM2, &val);
> + if (err < 0)
> + return err;
> + data->alarm |= ALARM2(val);
> + }
> +
> + err = adt7470_read_word_data(data, ADT7470_REG_ALARM1_MASK, &val);
> + if (err < 0)
> + return err;
> + data->alarms_mask = val;
>
> return 0;
> }
>
> static int adt7470_update_limits(struct adt7470_data *data)
> {
> - struct i2c_client *client = data->client;
> + unsigned int val;
> + int err;
> int i;
>
> for (i = 0; i < ADT7470_TEMP_COUNT; i++) {
> - data->temp_min[i] = i2c_smbus_read_byte_data(client,
> - ADT7470_TEMP_MIN_REG(i));
> - data->temp_max[i] = i2c_smbus_read_byte_data(client,
> - ADT7470_TEMP_MAX_REG(i));
> + err = regmap_read(data->regmap, ADT7470_TEMP_MIN_REG(i), &val);
> + if (err < 0)
> + return err;
> + data->temp_min[i] = (s8)val;
> + err = regmap_read(data->regmap, ADT7470_TEMP_MAX_REG(i), &val);
> + if (err < 0)
> + return err;
> + data->temp_max[i] = (s8)val;
> }
>
> for (i = 0; i < ADT7470_FAN_COUNT; i++) {
> - data->fan_min[i] = adt7470_read_word_data(client,
> - ADT7470_REG_FAN_MIN(i));
> - data->fan_max[i] = adt7470_read_word_data(client,
> - ADT7470_REG_FAN_MAX(i));
> + err = adt7470_read_word_data(data, ADT7470_REG_FAN_MIN(i), &val);
> + if (err < 0)
> + return err;
> + data->fan_min[i] = val;
> + err = adt7470_read_word_data(data, ADT7470_REG_FAN_MAX(i), &val);
> + if (err < 0)
> + return err;
> + data->fan_max[i] = val;
> }
>
> for (i = 0; i < ADT7470_PWM_COUNT; i++) {
> - data->pwm_max[i] = i2c_smbus_read_byte_data(client,
> - ADT7470_REG_PWM_MAX(i));
> - data->pwm_min[i] = i2c_smbus_read_byte_data(client,
> - ADT7470_REG_PWM_MIN(i));
> - data->pwm_tmin[i] = i2c_smbus_read_byte_data(client,
> - ADT7470_REG_PWM_TMIN(i));
> + err = regmap_read(data->regmap, ADT7470_REG_PWM_MAX(i), &val);
> + if (err < 0)
> + return err;
> + data->pwm_max[i] = val;
> + err = regmap_read(data->regmap, ADT7470_REG_PWM_MIN(i), &val);
> + if (err < 0)
> + return err;
> + data->pwm_min[i] = val;
> + err = regmap_read(data->regmap, ADT7470_REG_PWM_TMIN(i), &val);
> + if (err < 0)
> + return err;
> + data->pwm_tmin[i] = (s8)val;
> }
>
> return 0;
> @@ -491,8 +551,8 @@ static ssize_t temp_min_store(struct device *dev,
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> struct adt7470_data *data = dev_get_drvdata(dev);
> - struct i2c_client *client = data->client;
> long temp;
> + int err;
>
> if (kstrtol(buf, 10, &temp))
> return -EINVAL;
> @@ -502,11 +562,11 @@ static ssize_t temp_min_store(struct device *dev,
>
> mutex_lock(&data->lock);
> data->temp_min[attr->index] = temp;
> - i2c_smbus_write_byte_data(client, ADT7470_TEMP_MIN_REG(attr->index),
> + err = regmap_write(data->regmap, ADT7470_TEMP_MIN_REG(attr->index),
> temp);
> mutex_unlock(&data->lock);
>
> - return count;
> + return err < 0 ? err : count;
> }
>
> static ssize_t temp_max_show(struct device *dev,
> @@ -527,8 +587,8 @@ static ssize_t temp_max_store(struct device *dev,
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> struct adt7470_data *data = dev_get_drvdata(dev);
> - struct i2c_client *client = data->client;
> long temp;
> + int err;
>
> if (kstrtol(buf, 10, &temp))
> return -EINVAL;
> @@ -538,11 +598,10 @@ static ssize_t temp_max_store(struct device *dev,
>
> mutex_lock(&data->lock);
> data->temp_max[attr->index] = temp;
> - i2c_smbus_write_byte_data(client, ADT7470_TEMP_MAX_REG(attr->index),
> - temp);
> + err = regmap_write(data->regmap, ADT7470_TEMP_MAX_REG(attr->index), temp);
> mutex_unlock(&data->lock);
>
> - return count;
> + return err < 0 ? err : count;
> }
>
> static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
> @@ -575,6 +634,7 @@ static ssize_t alarm_mask_store(struct device *dev,
> {
> struct adt7470_data *data = dev_get_drvdata(dev);
> long mask;
> + int err;
>
> if (kstrtoul(buf, 0, &mask))
> return -EINVAL;
> @@ -584,10 +644,10 @@ static ssize_t alarm_mask_store(struct device *dev,
>
> mutex_lock(&data->lock);
> data->alarms_mask = mask;
> - adt7470_write_word_data(data->client, ADT7470_REG_ALARM1_MASK, mask);
> + err = adt7470_write_word_data(data, ADT7470_REG_ALARM1_MASK, mask);
> mutex_unlock(&data->lock);
>
> - return count;
> + return err < 0 ? err : count;
> }
>
> static ssize_t fan_max_show(struct device *dev,
> @@ -612,8 +672,8 @@ static ssize_t fan_max_store(struct device *dev,
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> struct adt7470_data *data = dev_get_drvdata(dev);
> - struct i2c_client *client = data->client;
> long temp;
> + int err;
>
> if (kstrtol(buf, 10, &temp) || !temp)
> return -EINVAL;
> @@ -623,10 +683,10 @@ static ssize_t fan_max_store(struct device *dev,
>
> mutex_lock(&data->lock);
> data->fan_max[attr->index] = temp;
> - adt7470_write_word_data(client, ADT7470_REG_FAN_MAX(attr->index), temp);
> + err = adt7470_write_word_data(data, ADT7470_REG_FAN_MAX(attr->index), temp);
> mutex_unlock(&data->lock);
>
> - return count;
> + return err < 0 ? err : count;
> }
>
> static ssize_t fan_min_show(struct device *dev,
> @@ -651,8 +711,8 @@ static ssize_t fan_min_store(struct device *dev,
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> struct adt7470_data *data = dev_get_drvdata(dev);
> - struct i2c_client *client = data->client;
> long temp;
> + int err;
>
> if (kstrtol(buf, 10, &temp) || !temp)
> return -EINVAL;
> @@ -662,10 +722,10 @@ static ssize_t fan_min_store(struct device *dev,
>
> mutex_lock(&data->lock);
> data->fan_min[attr->index] = temp;
> - adt7470_write_word_data(client, ADT7470_REG_FAN_MIN(attr->index), temp);
> + err = adt7470_write_word_data(data, ADT7470_REG_FAN_MIN(attr->index), temp);
> mutex_unlock(&data->lock);
>
> - return count;
> + return err < 0 ? err : count;
> }
>
> static ssize_t fan_show(struct device *dev, struct device_attribute *devattr,
> @@ -700,24 +760,20 @@ static ssize_t force_pwm_max_store(struct device *dev,
> const char *buf, size_t count)
> {
> struct adt7470_data *data = dev_get_drvdata(dev);
> - struct i2c_client *client = data->client;
> long temp;
> - u8 reg;
> + int err;
>
> if (kstrtol(buf, 10, &temp))
> return -EINVAL;
>
> mutex_lock(&data->lock);
> data->force_pwm_max = temp;
> - reg = i2c_smbus_read_byte_data(client, ADT7470_REG_CFG);
> - if (temp)
> - reg |= ADT7470_FSPD_MASK;
> - else
> - reg &= ~ADT7470_FSPD_MASK;
> - i2c_smbus_write_byte_data(client, ADT7470_REG_CFG, reg);
> + err = regmap_update_bits(data->regmap, ADT7470_REG_CFG,
> + ADT7470_FSPD_MASK,
> + temp ? ADT7470_FSPD_MASK : 0);
> mutex_unlock(&data->lock);
>
> - return count;
> + return err < 0 ? err : count;
> }
>
> static ssize_t pwm_show(struct device *dev, struct device_attribute *devattr,
> @@ -737,8 +793,8 @@ static ssize_t pwm_store(struct device *dev, struct device_attribute *devattr,
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> struct adt7470_data *data = dev_get_drvdata(dev);
> - struct i2c_client *client = data->client;
> long temp;
> + int err;
>
> if (kstrtol(buf, 10, &temp))
> return -EINVAL;
> @@ -747,10 +803,10 @@ static ssize_t pwm_store(struct device *dev, struct device_attribute *devattr,
>
> mutex_lock(&data->lock);
> data->pwm[attr->index] = temp;
> - i2c_smbus_write_byte_data(client, ADT7470_REG_PWM(attr->index), temp);
> + err = regmap_write(data->regmap, ADT7470_REG_PWM(attr->index), temp);
> mutex_unlock(&data->lock);
>
> - return count;
> + return err < 0 ? err : count;
> }
>
> /* These are the valid PWM frequencies to the nearest Hz */
> @@ -762,13 +818,20 @@ static ssize_t pwm1_freq_show(struct device *dev,
> struct device_attribute *devattr, char *buf)
> {
> struct adt7470_data *data = adt7470_update_device(dev);
> - unsigned char cfg_reg_1;
> - unsigned char cfg_reg_2;
> + unsigned int cfg_reg_1, cfg_reg_2;
> int index;
> + int err;
> +
> + if (IS_ERR(data))
> + return PTR_ERR(data);
>
> mutex_lock(&data->lock);
> - cfg_reg_1 = i2c_smbus_read_byte_data(data->client, ADT7470_REG_CFG);
> - cfg_reg_2 = i2c_smbus_read_byte_data(data->client, ADT7470_REG_CFG_2);
> + err = regmap_read(data->regmap, ADT7470_REG_CFG, &cfg_reg_1);
> + if (err < 0)
> + goto out;
> + err = regmap_read(data->regmap, ADT7470_REG_CFG_2, &cfg_reg_2);
> + if (err < 0)
> + goto out;
> mutex_unlock(&data->lock);
>
> index = (cfg_reg_2 & ADT7470_FREQ_MASK) >> ADT7470_FREQ_SHIFT;
> @@ -778,6 +841,10 @@ static ssize_t pwm1_freq_show(struct device *dev,
> index = ARRAY_SIZE(adt7470_freq_map) - 1;
>
> return scnprintf(buf, PAGE_SIZE, "%d\n", adt7470_freq_map[index]);
> +
> +out:
> + mutex_unlock(&data->lock);
> + return err;
> }
>
> static ssize_t pwm1_freq_store(struct device *dev,
> @@ -785,11 +852,10 @@ static ssize_t pwm1_freq_store(struct device *dev,
> const char *buf, size_t count)
> {
> struct adt7470_data *data = dev_get_drvdata(dev);
> - struct i2c_client *client = data->client;
> long freq;
> int index;
> int low_freq = ADT7470_CFG_LF;
> - unsigned char val;
> + int err;
>
> if (kstrtol(buf, 10, &freq))
> return -EINVAL;
> @@ -805,16 +871,19 @@ static ssize_t pwm1_freq_store(struct device *dev,
>
> mutex_lock(&data->lock);
> /* Configuration Register 1 */
> - val = i2c_smbus_read_byte_data(client, ADT7470_REG_CFG);
> - i2c_smbus_write_byte_data(client, ADT7470_REG_CFG,
> - (val & ~ADT7470_CFG_LF) | low_freq);
> + err = regmap_update_bits(data->regmap, ADT7470_REG_CFG,
> + ADT7470_CFG_LF, low_freq);
> + if (err < 0)
> + goto out;
> +
> /* Configuration Register 2 */
> - val = i2c_smbus_read_byte_data(client, ADT7470_REG_CFG_2);
> - i2c_smbus_write_byte_data(client, ADT7470_REG_CFG_2,
> - (val & ~ADT7470_FREQ_MASK) | (index << ADT7470_FREQ_SHIFT));
> + err = regmap_update_bits(data->regmap, ADT7470_REG_CFG_2,
> + ADT7470_FREQ_MASK,
> + index << ADT7470_FREQ_SHIFT);
> +out:
> mutex_unlock(&data->lock);
>
> - return count;
> + return err < 0 ? err : count;
> }
>
> static ssize_t pwm_max_show(struct device *dev,
> @@ -835,8 +904,8 @@ static ssize_t pwm_max_store(struct device *dev,
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> struct adt7470_data *data = dev_get_drvdata(dev);
> - struct i2c_client *client = data->client;
> long temp;
> + int err;
>
> if (kstrtol(buf, 10, &temp))
> return -EINVAL;
> @@ -845,11 +914,11 @@ static ssize_t pwm_max_store(struct device *dev,
>
> mutex_lock(&data->lock);
> data->pwm_max[attr->index] = temp;
> - i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_MAX(attr->index),
> - temp);
> + err = regmap_write(data->regmap, ADT7470_REG_PWM_MAX(attr->index),
> + temp);
> mutex_unlock(&data->lock);
>
> - return count;
> + return err < 0 ? err : count;
> }
>
> static ssize_t pwm_min_show(struct device *dev,
> @@ -870,8 +939,8 @@ static ssize_t pwm_min_store(struct device *dev,
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> struct adt7470_data *data = dev_get_drvdata(dev);
> - struct i2c_client *client = data->client;
> long temp;
> + int err;
>
> if (kstrtol(buf, 10, &temp))
> return -EINVAL;
> @@ -880,11 +949,11 @@ static ssize_t pwm_min_store(struct device *dev,
>
> mutex_lock(&data->lock);
> data->pwm_min[attr->index] = temp;
> - i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_MIN(attr->index),
> - temp);
> + err = regmap_write(data->regmap, ADT7470_REG_PWM_MIN(attr->index),
> + temp);
> mutex_unlock(&data->lock);
>
> - return count;
> + return err < 0 ? err : count;
> }
>
> static ssize_t pwm_tmax_show(struct device *dev,
> @@ -918,8 +987,8 @@ static ssize_t pwm_tmin_store(struct device *dev,
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> struct adt7470_data *data = dev_get_drvdata(dev);
> - struct i2c_client *client = data->client;
> long temp;
> + int err;
>
> if (kstrtol(buf, 10, &temp))
> return -EINVAL;
> @@ -929,11 +998,11 @@ static ssize_t pwm_tmin_store(struct device *dev,
>
> mutex_lock(&data->lock);
> data->pwm_tmin[attr->index] = temp;
> - i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_TMIN(attr->index),
> - temp);
> + err = regmap_write(data->regmap, ADT7470_REG_PWM_TMIN(attr->index),
> + temp);
> mutex_unlock(&data->lock);
>
> - return count;
> + return err < 0 ? err : count;
> }
>
> static ssize_t pwm_auto_show(struct device *dev,
> @@ -954,11 +1023,9 @@ static ssize_t pwm_auto_store(struct device *dev,
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> struct adt7470_data *data = dev_get_drvdata(dev);
> - struct i2c_client *client = data->client;
> - int pwm_auto_reg = ADT7470_REG_PWM_CFG(attr->index);
> int pwm_auto_reg_mask;
> long temp;
> - u8 reg;
> + int err;
>
> if (kstrtol(buf, 10, &temp))
> return -EINVAL;
> @@ -974,15 +1041,12 @@ static ssize_t pwm_auto_store(struct device *dev,
>
> mutex_lock(&data->lock);
> data->pwm_automatic[attr->index] = temp;
> - reg = i2c_smbus_read_byte_data(client, pwm_auto_reg);
> - if (temp)
> - reg |= pwm_auto_reg_mask;
> - else
> - reg &= ~pwm_auto_reg_mask;
> - i2c_smbus_write_byte_data(client, pwm_auto_reg, reg);
> + err = regmap_update_bits(data->regmap, ADT7470_REG_PWM_CFG(attr->index),
> + pwm_auto_reg_mask,
> + temp ? pwm_auto_reg_mask : 0);
> mutex_unlock(&data->lock);
>
> - return count;
> + return err < 0 ? err : count;
> }
>
> static ssize_t pwm_auto_temp_show(struct device *dev,
> @@ -1017,10 +1081,10 @@ static ssize_t pwm_auto_temp_store(struct device *dev,
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> struct adt7470_data *data = dev_get_drvdata(dev);
> - struct i2c_client *client = data->client;
> int pwm_auto_reg = ADT7470_REG_PWM_AUTO_TEMP(attr->index);
> + unsigned int mask, val;
> long temp;
> - u8 reg;
> + int err;
>
> if (kstrtol(buf, 10, &temp))
> return -EINVAL;
> @@ -1031,20 +1095,19 @@ static ssize_t pwm_auto_temp_store(struct device *dev,
>
> mutex_lock(&data->lock);
> data->pwm_automatic[attr->index] = temp;
> - reg = i2c_smbus_read_byte_data(client, pwm_auto_reg);
>
> if (!(attr->index % 2)) {
> - reg &= 0xF;
> - reg |= (temp << 4) & 0xF0;
> + mask = 0xF0;
> + val = (temp << 4) & 0xF0;
> } else {
> - reg &= 0xF0;
> - reg |= temp & 0xF;
> + mask = 0x0F;
> + val = temp & 0x0F;
> }
>
> - i2c_smbus_write_byte_data(client, pwm_auto_reg, reg);
> + err = regmap_update_bits(data->regmap, pwm_auto_reg, mask, val);
> mutex_unlock(&data->lock);
>
> - return count;
> + return err < 0 ? err : count;
> }
>
> static ssize_t alarm_show(struct device *dev,
> @@ -1053,6 +1116,9 @@ static ssize_t alarm_show(struct device *dev,
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> struct adt7470_data *data = adt7470_update_device(dev);
>
> + if (IS_ERR(data))
> + return PTR_ERR(data);
> +
> if (data->alarm & attr->index)
> return sprintf(buf, "1\n");
> else
> @@ -1288,23 +1354,19 @@ static int adt7470_detect(struct i2c_client *client,
> return 0;
> }
>
> -static void adt7470_init_client(struct i2c_client *client)
> -{
> - int reg = i2c_smbus_read_byte_data(client, ADT7470_REG_CFG);
> -
> - if (reg < 0) {
> - dev_err(&client->dev, "cannot read configuration register\n");
> - } else {
> - /* start monitoring (and do a self-test) */
> - i2c_smbus_write_byte_data(client, ADT7470_REG_CFG, reg | 3);
> - }
> -}
> +static const struct regmap_config adt7470_regmap_config = {
> + .reg_bits = 8,
> + .val_bits = 8,
> + .use_single_read = true,
> + .use_single_write = true,
> +};
>
> static int adt7470_probe(struct i2c_client *client)
> {
> struct device *dev = &client->dev;
> struct adt7470_data *data;
> struct device *hwmon_dev;
> + int err;
>
> data = devm_kzalloc(dev, sizeof(struct adt7470_data), GFP_KERNEL);
> if (!data)
> @@ -1312,15 +1374,21 @@ static int adt7470_probe(struct i2c_client *client)
>
> data->num_temp_sensors = -1;
> data->auto_update_interval = AUTO_UPDATE_INTERVAL;
> + data->regmap = devm_regmap_init_i2c(client, &adt7470_regmap_config);
> + if (IS_ERR(data->regmap))
> + return PTR_ERR(data->regmap);
>
> i2c_set_clientdata(client, data);
> - data->client = client;
> mutex_init(&data->lock);
>
> dev_info(&client->dev, "%s chip found\n", client->name);
>
> /* Initialize the ADT7470 chip */
> - adt7470_init_client(client);
> + err = regmap_update_bits(data->regmap, ADT7470_REG_CFG,
> + ADT7470_STRT_MASK | ADT7470_TEST_MASK,
> + ADT7470_STRT_MASK | ADT7470_TEST_MASK);
> + if (err < 0)
> + return err;
>
> /* Register sysfs hooks */
> hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,