[PATCH v2] hwmon (max6639): Use regmap

From: Naresh Solanki
Date: Tue Apr 30 2024 - 17:05:51 EST

Add regmap support & remove local caching.

Signed-off-by: Naresh Solanki <naresh.solanki@xxxxxxxxxxxxx>
---
drivers/hwmon/Kconfig | 1 +
drivers/hwmon/max6639.c | 310 ++++++++++++++++++++--------------------
2 files changed, 154 insertions(+), 157 deletions(-)

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index bafc0058c728..e14ae18a973b 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1233,6 +1233,7 @@ config SENSORS_MAX6621
config SENSORS_MAX6639
tristate "Maxim MAX6639 sensor chip"
depends on I2C
+ select REGMAP_I2C
help
If you say yes here you get support for the MAX6639
sensor chips.
diff --git a/drivers/hwmon/max6639.c b/drivers/hwmon/max6639.c
index 5dd0349e8bd0..b12d2098e259 100644
--- a/drivers/hwmon/max6639.c
+++ b/drivers/hwmon/max6639.c
@@ -20,6 +20,7 @@
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/platform_data/max6639.h>
+#include <linux/regmap.h>

/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
@@ -57,6 +58,8 @@ static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };

#define MAX6639_FAN_CONFIG3_THERM_FULL_SPEED 0x40

+#define MAX6639_NDEV 2
+
static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 };

#define FAN_FROM_REG(val, rpm_range) ((val) == 0 || (val) == 255 ? \
@@ -67,22 +70,11 @@ static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 };
* Client data (each client gets its own)
*/
struct max6639_data {
- struct i2c_client *client;
+ struct regmap *regmap;
struct mutex update_lock;
- bool valid; /* true if following fields are valid */
- unsigned long last_updated; /* In jiffies */
-
- /* Register values sampled regularly */
- u16 temp[2]; /* Temperature, in 1/8 C, 0..255 C */
- bool temp_fault[2]; /* Detected temperature diode failure */
- u8 fan[2]; /* Register value: TACH count for fans >=30 */
- u8 status; /* Detected channel alarms and fan failures */

/* Register values only written to */
- u8 pwm[2]; /* Register value: Duty cycle 0..120 */
- u8 temp_therm[2]; /* THERM Temperature, 0..255 C (->_max) */
- u8 temp_alert[2]; /* ALERT Temperature, 0..255 C (->_crit) */
- u8 temp_ot[2]; /* OT Temperature, 0..255 C (->_emergency) */
+ u8 pwm[MAX6639_NDEV]; /* Register value: Duty cycle 0..120 */

/* Register values initialized only once */
u8 ppr; /* Pulses per rotation 0..3 for 1..4 ppr */
@@ -92,90 +84,58 @@ struct max6639_data {
struct regulator *reg;
};

-static struct max6639_data *max6639_update_device(struct device *dev)
-{
- struct max6639_data *data = dev_get_drvdata(dev);
- struct i2c_client *client = data->client;
- struct max6639_data *ret = data;
- int i;
- int status_reg;
-
- mutex_lock(&data->update_lock);
-
- if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) {
- int res;
-
- dev_dbg(&client->dev, "Starting max6639 update\n");
-
- status_reg = i2c_smbus_read_byte_data(client,
- MAX6639_REG_STATUS);
- if (status_reg < 0) {
- ret = ERR_PTR(status_reg);
- goto abort;
- }
-
- data->status = status_reg;
-
- for (i = 0; i < 2; i++) {
- res = i2c_smbus_read_byte_data(client,
- MAX6639_REG_FAN_CNT(i));
- if (res < 0) {
- ret = ERR_PTR(res);
- goto abort;
- }
- data->fan[i] = res;
-
- res = i2c_smbus_read_byte_data(client,
- MAX6639_REG_TEMP_EXT(i));
- if (res < 0) {
- ret = ERR_PTR(res);
- goto abort;
- }
- data->temp[i] = res >> 5;
- data->temp_fault[i] = res & 0x01;
-
- res = i2c_smbus_read_byte_data(client,
- MAX6639_REG_TEMP(i));
- if (res < 0) {
- ret = ERR_PTR(res);
- goto abort;
- }
- data->temp[i] |= res << 3;
- }
-
- data->last_updated = jiffies;
- data->valid = true;
- }
-abort:
- mutex_unlock(&data->update_lock);
-
- return ret;
-}
-
static ssize_t temp_input_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
long temp;
- struct max6639_data *data = max6639_update_device(dev);
+ struct max6639_data *data = dev_get_drvdata(dev);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+ unsigned int val;
+ int res;

if (IS_ERR(data))
return PTR_ERR(data);

- temp = data->temp[attr->index] * 125;
+ mutex_lock(&data->update_lock);
+ res = regmap_read(data->regmap, MAX6639_REG_TEMP_EXT(attr->index), &val);
+ if (res < 0)
+ goto exit;
+
+ temp = val >> 5;
+ res = regmap_read(data->regmap, MAX6639_REG_TEMP(attr->index), &val);
+ if (res < 0)
+ goto exit;
+
+ temp |= val << 3;
+ temp *= 125;
+
+exit:
+ mutex_unlock(&data->update_lock);
+ if (res < 0)
+ return res;
+
return sprintf(buf, "%ld\n", temp);
}

static ssize_t temp_fault_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
- struct max6639_data *data = max6639_update_device(dev);
+ struct max6639_data *data = dev_get_drvdata(dev);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+ unsigned int val;
+ int res;

if (IS_ERR(data))
return PTR_ERR(data);

- return sprintf(buf, "%d\n", data->temp_fault[attr->index]);
+ mutex_lock(&data->update_lock);
+ res = regmap_read(data->regmap, MAX6639_REG_TEMP_EXT(attr->index), &val);
+ mutex_unlock(&data->update_lock);
+
+ if (res < 0)
+ return res;
+
+ return sprintf(buf, "%d\n", val & 1);
}

static ssize_t temp_max_show(struct device *dev,
@@ -183,8 +143,17 @@ static ssize_t temp_max_show(struct device *dev,
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
struct max6639_data *data = dev_get_drvdata(dev);
+ unsigned int val;
+ int res;

- return sprintf(buf, "%d\n", (data->temp_therm[attr->index] * 1000));
+ mutex_lock(&data->update_lock);
+ res = regmap_read(data->regmap, MAX6639_REG_THERM_LIMIT(attr->index), &val);
+ mutex_unlock(&data->update_lock);
+
+ if (res < 0)
+ return res;
+
+ return sprintf(buf, "%d\n", (val * 1000));
}

static ssize_t temp_max_store(struct device *dev,
@@ -193,7 +162,6 @@ static ssize_t temp_max_store(struct device *dev,
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
struct max6639_data *data = dev_get_drvdata(dev);
- struct i2c_client *client = data->client;
unsigned long val;
int res;

@@ -202,10 +170,8 @@ static ssize_t temp_max_store(struct device *dev,
return res;

mutex_lock(&data->update_lock);
- data->temp_therm[attr->index] = TEMP_LIMIT_TO_REG(val);
- i2c_smbus_write_byte_data(client,
- MAX6639_REG_THERM_LIMIT(attr->index),
- data->temp_therm[attr->index]);
+ regmap_write(data->regmap, MAX6639_REG_THERM_LIMIT(attr->index),
+ TEMP_LIMIT_TO_REG(val));
mutex_unlock(&data->update_lock);
return count;
}
@@ -215,8 +181,17 @@ static ssize_t temp_crit_show(struct device *dev,
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
struct max6639_data *data = dev_get_drvdata(dev);
+ unsigned int val;
+ int res;
+
+ mutex_lock(&data->update_lock);
+ res = regmap_read(data->regmap, MAX6639_REG_ALERT_LIMIT(attr->index), &val);
+ mutex_unlock(&data->update_lock);

- return sprintf(buf, "%d\n", (data->temp_alert[attr->index] * 1000));
+ if (res < 0)
+ return res;
+
+ return sprintf(buf, "%d\n", (val * 1000));
}

static ssize_t temp_crit_store(struct device *dev,
@@ -225,7 +200,6 @@ static ssize_t temp_crit_store(struct device *dev,
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
struct max6639_data *data = dev_get_drvdata(dev);
- struct i2c_client *client = data->client;
unsigned long val;
int res;

@@ -234,10 +208,8 @@ static ssize_t temp_crit_store(struct device *dev,
return res;

mutex_lock(&data->update_lock);
- data->temp_alert[attr->index] = TEMP_LIMIT_TO_REG(val);
- i2c_smbus_write_byte_data(client,
- MAX6639_REG_ALERT_LIMIT(attr->index),
- data->temp_alert[attr->index]);
+ regmap_write(data->regmap, MAX6639_REG_ALERT_LIMIT(attr->index),
+ TEMP_LIMIT_TO_REG(val));
mutex_unlock(&data->update_lock);
return count;
}
@@ -248,8 +220,17 @@ static ssize_t temp_emergency_show(struct device *dev,
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
struct max6639_data *data = dev_get_drvdata(dev);
+ unsigned int val;
+ int res;

- return sprintf(buf, "%d\n", (data->temp_ot[attr->index] * 1000));
+ mutex_lock(&data->update_lock);
+ res = regmap_read(data->regmap, MAX6639_REG_OT_LIMIT(attr->index), &val);
+ mutex_unlock(&data->update_lock);
+
+ if (res < 0)
+ return res;
+
+ return sprintf(buf, "%d\n", (val * 1000));
}

static ssize_t temp_emergency_store(struct device *dev,
@@ -258,7 +239,6 @@ static ssize_t temp_emergency_store(struct device *dev,
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
struct max6639_data *data = dev_get_drvdata(dev);
- struct i2c_client *client = data->client;
unsigned long val;
int res;

@@ -267,10 +247,7 @@ static ssize_t temp_emergency_store(struct device *dev,
return res;

mutex_lock(&data->update_lock);
- data->temp_ot[attr->index] = TEMP_LIMIT_TO_REG(val);
- i2c_smbus_write_byte_data(client,
- MAX6639_REG_OT_LIMIT(attr->index),
- data->temp_ot[attr->index]);
+ regmap_write(data->regmap, MAX6639_REG_OT_LIMIT(attr->index), TEMP_LIMIT_TO_REG(val));
mutex_unlock(&data->update_lock);
return count;
}
@@ -290,7 +267,6 @@ static ssize_t pwm_store(struct device *dev,
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
struct max6639_data *data = dev_get_drvdata(dev);
- struct i2c_client *client = data->client;
unsigned long val;
int res;

@@ -299,12 +275,9 @@ static ssize_t pwm_store(struct device *dev,
return res;

val = clamp_val(val, 0, 255);
-
- mutex_lock(&data->update_lock);
data->pwm[attr->index] = (u8)(val * 120 / 255);
- i2c_smbus_write_byte_data(client,
- MAX6639_REG_TARGTDUTY(attr->index),
- data->pwm[attr->index]);
+ mutex_lock(&data->update_lock);
+ regmap_write(data->regmap, MAX6639_REG_TARGTDUTY(attr->index), data->pwm[attr->index]);
mutex_unlock(&data->update_lock);
return count;
}
@@ -312,26 +285,35 @@ static ssize_t pwm_store(struct device *dev,
static ssize_t fan_input_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
- struct max6639_data *data = max6639_update_device(dev);
+ struct max6639_data *data = dev_get_drvdata(dev);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+ unsigned int val;
+ int res;

if (IS_ERR(data))
return PTR_ERR(data);

- return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[attr->index],
- data->rpm_range));
+ res = regmap_read(data->regmap, MAX6639_REG_FAN_CNT(attr->index), &val);
+ if (res < 0)
+ return res;
+
+ return sprintf(buf, "%d\n", FAN_FROM_REG(val, data->rpm_range));
}

static ssize_t alarm_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
- struct max6639_data *data = max6639_update_device(dev);
+ struct max6639_data *data = dev_get_drvdata(dev);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+ unsigned int val;
+ int res;

if (IS_ERR(data))
return PTR_ERR(data);

- return sprintf(buf, "%d\n", !!(data->status & (1 << attr->index)));
+ res = regmap_read(data->regmap, MAX6639_REG_STATUS, &val);
+
+ return sprintf(buf, "%d\n", !!(val & (1 << attr->index)));
}

static SENSOR_DEVICE_ATTR_RO(temp1_input, temp_input, 0);
@@ -401,6 +383,11 @@ static int rpm_range_to_reg(int range)
return 1; /* default: 4000 RPM */
}

+static int max6639_set_ppr(struct max6639_data *data, u8 channel, u8 ppr)
+{
+ return regmap_write(data->regmap, MAX6639_REG_FAN_PPR(channel), ppr << 6);
+}
+
static int max6639_init_client(struct i2c_client *client,
struct max6639_data *data)
{
@@ -408,49 +395,43 @@ static int max6639_init_client(struct i2c_client *client,
dev_get_platdata(&client->dev);
int i;
int rpm_range = 1; /* default: 4000 RPM */
- int err;
+ int err, ppr;

/* Reset chip to default values, see below for GCONFIG setup */
- err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
- MAX6639_GCONFIG_POR);
+ err = regmap_write(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_POR);
if (err)
goto exit;

/* Fans pulse per revolution is 2 by default */
if (max6639_info && max6639_info->ppr > 0 &&
max6639_info->ppr < 5)
- data->ppr = max6639_info->ppr;
+ ppr = max6639_info->ppr;
else
- data->ppr = 2;
- data->ppr -= 1;
+ ppr = 2;
+ ppr -= 1;

if (max6639_info)
rpm_range = rpm_range_to_reg(max6639_info->rpm_range);
data->rpm_range = rpm_range;

- for (i = 0; i < 2; i++) {
+ for (i = 0; i < MAX6639_NDEV; i++) {

/* Set Fan pulse per revolution */
- err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_FAN_PPR(i),
- data->ppr << 6);
+ err = max6639_set_ppr(data, i, ppr);
if (err)
goto exit;

/* Fans config PWM, RPM */
- err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_FAN_CONFIG1(i),
- MAX6639_FAN_CONFIG1_PWM | rpm_range);
+ err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG1(i),
+ MAX6639_FAN_CONFIG1_PWM | rpm_range);
if (err)
goto exit;

/* Fans PWM polarity high by default */
if (max6639_info && max6639_info->pwm_polarity == 0)
- err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_FAN_CONFIG2a(i), 0x00);
+ err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG2a(i), 0x00);
else
- err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_FAN_CONFIG2a(i), 0x02);
+ err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG2a(i), 0x02);
if (err)
goto exit;

@@ -458,42 +439,31 @@ static int max6639_init_client(struct i2c_client *client,
* /THERM full speed enable,
* PWM frequency 25kHz, see also GCONFIG below
*/
- err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_FAN_CONFIG3(i),
- MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03);
+ err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG3(i),
+ MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03);
if (err)
goto exit;

/* Max. temp. 80C/90C/100C */
- data->temp_therm[i] = 80;
- data->temp_alert[i] = 90;
- data->temp_ot[i] = 100;
- err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_THERM_LIMIT(i),
- data->temp_therm[i]);
+ err = regmap_write(data->regmap, MAX6639_REG_THERM_LIMIT(i), 80);
if (err)
goto exit;
- err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_ALERT_LIMIT(i),
- data->temp_alert[i]);
+ err = regmap_write(data->regmap, MAX6639_REG_ALERT_LIMIT(i), 90);
if (err)
goto exit;
- err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_OT_LIMIT(i), data->temp_ot[i]);
+ err = regmap_write(data->regmap, MAX6639_REG_OT_LIMIT(i), 100);
if (err)
goto exit;

/* PWM 120/120 (i.e. 100%) */
- data->pwm[i] = 120;
- err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_TARGTDUTY(i), data->pwm[i]);
+ err = regmap_write(data->regmap, MAX6639_REG_TARGTDUTY(i), 120);
if (err)
goto exit;
}
/* Start monitoring */
- err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
- MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL |
- MAX6639_GCONFIG_PWM_FREQ_HI);
+ err = regmap_write(data->regmap, MAX6639_REG_GCONFIG,
+ MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL |
+ MAX6639_GCONFIG_PWM_FREQ_HI);
exit:
return err;
}
@@ -524,6 +494,30 @@ static void max6639_regulator_disable(void *data)
regulator_disable(data);
}

+static bool max6639_regmap_is_volatile(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case MAX6639_REG_TEMP(0):
+ case MAX6639_REG_TEMP_EXT(0):
+ case MAX6639_REG_TEMP(1):
+ case MAX6639_REG_TEMP_EXT(1):
+ case MAX6639_REG_STATUS:
+ case MAX6639_REG_FAN_CNT(0):
+ case MAX6639_REG_FAN_CNT(1):
+ return true;
+ default:
+ return false;
+ }
+}
+
+static const struct regmap_config max6639_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = MAX6639_REG_DEVREV,
+ .cache_type = REGCACHE_MAPLE,
+ .volatile_reg = max6639_regmap_is_volatile,
+};
+
static int max6639_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
@@ -535,7 +529,11 @@ static int max6639_probe(struct i2c_client *client)
if (!data)
return -ENOMEM;

- data->client = client;
+ data->regmap = devm_regmap_init_i2c(client, &max6639_regmap_config);
+ if (IS_ERR(data->regmap))
+ return dev_err_probe(dev,
+ PTR_ERR(data->regmap),
+ "regmap initialization failed\n");

data->reg = devm_regulator_get_optional(dev, "fan");
if (IS_ERR(data->reg)) {
@@ -573,25 +571,24 @@ static int max6639_probe(struct i2c_client *client)

static int max6639_suspend(struct device *dev)
{
- struct i2c_client *client = to_i2c_client(dev);
struct max6639_data *data = dev_get_drvdata(dev);
- int ret = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG);
+ int ret, err;

- if (ret < 0)
- return ret;
+ err = regmap_read(data->regmap, MAX6639_REG_GCONFIG, &ret);
+
+ if (err < 0)
+ return err;

if (data->reg)
regulator_disable(data->reg);

- return i2c_smbus_write_byte_data(client,
- MAX6639_REG_GCONFIG, ret | MAX6639_GCONFIG_STANDBY);
+ return regmap_write(data->regmap, MAX6639_REG_GCONFIG, ret | MAX6639_GCONFIG_STANDBY);
}

static int max6639_resume(struct device *dev)
{
- struct i2c_client *client = to_i2c_client(dev);
struct max6639_data *data = dev_get_drvdata(dev);
- int ret;
+ int ret, err;

if (data->reg) {
ret = regulator_enable(data->reg);
@@ -601,12 +598,11 @@ static int max6639_resume(struct device *dev)
}
}

- ret = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG);
- if (ret < 0)
- return ret;
+ err = regmap_read(data->regmap, MAX6639_REG_GCONFIG, &ret);
+ if (err < 0)
+ return err;

- return i2c_smbus_write_byte_data(client,
- MAX6639_REG_GCONFIG, ret & ~MAX6639_GCONFIG_STANDBY);
+ return regmap_write(data->regmap, MAX6639_REG_GCONFIG, ret & ~MAX6639_GCONFIG_STANDBY);
}

static const struct i2c_device_id max6639_id[] = {

base-commit: 8b3aa2c488653fa1e127cf6e11499a8cbbaccad0
--
2.42.0