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path: root/drivers/hwmon/max31827.c
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Diffstat (limited to 'drivers/hwmon/max31827.c')
-rw-r--r--drivers/hwmon/max31827.c85
1 files changed, 32 insertions, 53 deletions
diff --git a/drivers/hwmon/max31827.c b/drivers/hwmon/max31827.c
index f8a13b30f100..9b2e56c040df 100644
--- a/drivers/hwmon/max31827.c
+++ b/drivers/hwmon/max31827.c
@@ -10,7 +10,6 @@
#include <linux/delay.h>
#include <linux/hwmon.h>
#include <linux/i2c.h>
-#include <linux/mutex.h>
#include <linux/of_device.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
@@ -24,6 +23,7 @@
#define MAX31827_CONFIGURATION_1SHOT_MASK BIT(0)
#define MAX31827_CONFIGURATION_CNV_RATE_MASK GENMASK(3, 1)
+#define MAX31827_CONFIGURATION_PEC_EN_MASK BIT(4)
#define MAX31827_CONFIGURATION_TIMEOUT_MASK BIT(5)
#define MAX31827_CONFIGURATION_RESOLUTION_MASK GENMASK(7, 6)
#define MAX31827_CONFIGURATION_ALRM_POL_MASK BIT(8)
@@ -46,6 +46,11 @@
#define MAX31827_M_DGR_TO_16_BIT(x) (((x) << 4) / 1000)
#define MAX31827_DEVICE_ENABLE(x) ((x) ? 0xA : 0x0)
+/*
+ * The enum passed in the .data pointer of struct of_device_id must
+ * start with a value != 0 since that is a requirement for using
+ * device_get_match_data().
+ */
enum chips { max31827 = 1, max31828, max31829 };
enum max31827_cnv {
@@ -93,7 +98,6 @@ struct max31827_state {
/*
* Prevent simultaneous access to the i2c client.
*/
- struct mutex lock;
struct regmap *regmap;
bool enable;
unsigned int resolution;
@@ -117,30 +121,23 @@ static int shutdown_write(struct max31827_state *st, unsigned int reg,
* Before the Temperature Threshold Alarm, Alarm Hysteresis Threshold
* and Resolution bits from Configuration register are changed over I2C,
* the part must be in shutdown mode.
- *
- * Mutex is used to ensure, that some other process doesn't change the
- * configuration register.
*/
- mutex_lock(&st->lock);
-
if (!st->enable) {
if (!mask)
- ret = regmap_write(st->regmap, reg, val);
- else
- ret = regmap_update_bits(st->regmap, reg, mask, val);
- goto unlock;
+ return regmap_write(st->regmap, reg, val);
+ return regmap_update_bits(st->regmap, reg, mask, val);
}
ret = regmap_read(st->regmap, MAX31827_CONFIGURATION_REG, &cfg);
if (ret)
- goto unlock;
+ return ret;
cnv_rate = MAX31827_CONFIGURATION_CNV_RATE_MASK & cfg;
cfg = cfg & ~(MAX31827_CONFIGURATION_1SHOT_MASK |
MAX31827_CONFIGURATION_CNV_RATE_MASK);
ret = regmap_write(st->regmap, MAX31827_CONFIGURATION_REG, cfg);
if (ret)
- goto unlock;
+ return ret;
if (!mask)
ret = regmap_write(st->regmap, reg, val);
@@ -148,15 +145,11 @@ static int shutdown_write(struct max31827_state *st, unsigned int reg,
ret = regmap_update_bits(st->regmap, reg, mask, val);
if (ret)
- goto unlock;
-
- ret = regmap_update_bits(st->regmap, MAX31827_CONFIGURATION_REG,
- MAX31827_CONFIGURATION_CNV_RATE_MASK,
- cnv_rate);
+ return ret;
-unlock:
- mutex_unlock(&st->lock);
- return ret;
+ return regmap_update_bits(st->regmap, MAX31827_CONFIGURATION_REG,
+ MAX31827_CONFIGURATION_CNV_RATE_MASK,
+ cnv_rate);
}
static int write_alarm_val(struct max31827_state *st, unsigned int reg,
@@ -217,23 +210,13 @@ static int max31827_read(struct device *dev, enum hwmon_sensor_types type,
break;
case hwmon_temp_input:
- mutex_lock(&st->lock);
-
if (!st->enable) {
- /*
- * This operation requires mutex protection,
- * because the chip configuration should not
- * be changed during the conversion process.
- */
-
ret = regmap_update_bits(st->regmap,
MAX31827_CONFIGURATION_REG,
MAX31827_CONFIGURATION_1SHOT_MASK,
1);
- if (ret) {
- mutex_unlock(&st->lock);
+ if (ret)
return ret;
- }
msleep(max31827_conv_times[st->resolution]);
}
@@ -248,8 +231,6 @@ static int max31827_read(struct device *dev, enum hwmon_sensor_types type,
ret = regmap_read(st->regmap, MAX31827_T_REG, &uval);
- mutex_unlock(&st->lock);
-
if (ret)
break;
@@ -346,7 +327,6 @@ static int max31827_write(struct device *dev, enum hwmon_sensor_types type,
if (val >> 1)
return -EINVAL;
- mutex_lock(&st->lock);
/**
* The chip should not be enabled while a conversion is
* performed. Neither should the chip be enabled when
@@ -355,15 +335,11 @@ static int max31827_write(struct device *dev, enum hwmon_sensor_types type,
st->enable = val;
- ret = regmap_update_bits(st->regmap,
- MAX31827_CONFIGURATION_REG,
- MAX31827_CONFIGURATION_1SHOT_MASK |
- MAX31827_CONFIGURATION_CNV_RATE_MASK,
- MAX31827_DEVICE_ENABLE(val));
-
- mutex_unlock(&st->lock);
-
- return ret;
+ return regmap_update_bits(st->regmap,
+ MAX31827_CONFIGURATION_REG,
+ MAX31827_CONFIGURATION_1SHOT_MASK |
+ MAX31827_CONFIGURATION_CNV_RATE_MASK,
+ MAX31827_DEVICE_ENABLE(val));
case hwmon_temp_max:
return write_alarm_val(st, MAX31827_TH_REG, val);
@@ -382,7 +358,8 @@ static int max31827_write(struct device *dev, enum hwmon_sensor_types type,
}
case hwmon_chip:
- if (attr == hwmon_chip_update_interval) {
+ switch (attr) {
+ case hwmon_chip_update_interval:
if (!st->enable)
return -EINVAL;
@@ -410,14 +387,18 @@ static int max31827_write(struct device *dev, enum hwmon_sensor_types type,
return ret;
st->update_interval = val;
- }
- break;
+ return 0;
+ case hwmon_chip_pec:
+ return regmap_update_bits(st->regmap, MAX31827_CONFIGURATION_REG,
+ MAX31827_CONFIGURATION_PEC_EN_MASK,
+ val ? MAX31827_CONFIGURATION_PEC_EN_MASK : 0);
+ default:
+ return -EOPNOTSUPP;
+ }
default:
return -EOPNOTSUPP;
}
-
- return 0;
}
static ssize_t temp1_resolution_show(struct device *dev,
@@ -434,7 +415,7 @@ static ssize_t temp1_resolution_show(struct device *dev,
val = FIELD_GET(MAX31827_CONFIGURATION_RESOLUTION_MASK, val);
- return scnprintf(buf, PAGE_SIZE, "%u\n", max31827_resolutions[val]);
+ return sysfs_emit(buf, "%u\n", max31827_resolutions[val]);
}
static ssize_t temp1_resolution_store(struct device *dev,
@@ -583,7 +564,7 @@ static const struct hwmon_channel_info *max31827_info[] = {
HWMON_T_MIN_HYST | HWMON_T_MIN_ALARM |
HWMON_T_MAX | HWMON_T_MAX_HYST |
HWMON_T_MAX_ALARM),
- HWMON_CHANNEL_INFO(chip, HWMON_C_UPDATE_INTERVAL),
+ HWMON_CHANNEL_INFO(chip, HWMON_C_UPDATE_INTERVAL | HWMON_C_PEC),
NULL,
};
@@ -612,8 +593,6 @@ static int max31827_probe(struct i2c_client *client)
if (!st)
return -ENOMEM;
- mutex_init(&st->lock);
-
st->regmap = devm_regmap_init_i2c(client, &max31827_regmap);
if (IS_ERR(st->regmap))
return dev_err_probe(dev, PTR_ERR(st->regmap),
generated by cgit (git 2.34.1) at 2025-12-25 05:45:18 +0000