Convert to use with_info API to simplify the code and make it easier
to maintain. This also reduces code size by approximately 20%.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
 drivers/hwmon/amc6821.c | 743 +++++++++++++++++++++-------------------
 1 file changed, 386 insertions(+), 357 deletions(-)

diff --git a/drivers/hwmon/amc6821.c b/drivers/hwmon/amc6821.c
index 6ffab4288134..14d59aa4254b 100644
--- a/drivers/hwmon/amc6821.c
+++ b/drivers/hwmon/amc6821.c
@@ -6,6 +6,9 @@
  *
  * Based on max6650.c:
  * Copyright (C) 2007 Hans J. Koch <hjk@hansjkoch.de>
+ *
+ * Conversion to regmap and with_info API:
+ * Copyright (C) 2024 Guenter Roeck <linux@roeck-us.net>
  */
 
 #include <linux/bits.h>
@@ -106,28 +109,6 @@ module_param(init, int, 0444);
 #define AMC6821_STAT2_L_THERM		BIT(6)
 #define AMC6821_STAT2_THERM_IN		BIT(7)
 
-enum {IDX_TEMP1_INPUT = 0, IDX_TEMP1_MIN, IDX_TEMP1_MAX,
-	IDX_TEMP1_CRIT, IDX_TEMP2_INPUT, IDX_TEMP2_MIN,
-	IDX_TEMP2_MAX, IDX_TEMP2_CRIT,
-	TEMP_IDX_LEN, };
-
-static const u8 temp_reg[] = {AMC6821_REG_LTEMP_HI,
-			AMC6821_REG_LTEMP_LIMIT_MIN,
-			AMC6821_REG_LTEMP_LIMIT_MAX,
-			AMC6821_REG_LTEMP_CRIT,
-			AMC6821_REG_RTEMP_HI,
-			AMC6821_REG_RTEMP_LIMIT_MIN,
-			AMC6821_REG_RTEMP_LIMIT_MAX,
-			AMC6821_REG_RTEMP_CRIT, };
-
-enum {IDX_FAN1_INPUT = 0, IDX_FAN1_MIN, IDX_FAN1_MAX, IDX_FAN1_TARGET,
-	FAN1_IDX_LEN, };
-
-static const u8 fan_reg_low[] = {AMC6821_REG_TDATA_LOW,
-			AMC6821_REG_TACH_LLIMITL,
-			AMC6821_REG_TACH_HLIMITL,
-			AMC6821_REG_TACH_SETTINGL, };
-
 /*
  * Client data (each client gets its own)
  */
@@ -188,232 +169,323 @@ static int amc6821_init_auto_point_data(struct amc6821_data *data)
 	return 0;
 }
 
-static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
-			 char *buf)
+static int amc6821_temp_read_values(struct regmap *regmap, u32 attr, int channel, long *val)
 {
-	struct amc6821_data *data = dev_get_drvdata(dev);
-	int ix = to_sensor_dev_attr(devattr)->index;
+	int reg, err;
 	u32 regval;
-	int err;
 
-	err = regmap_read(data->regmap, temp_reg[ix], &regval);
-	if (err)
-		return err;
-
-	return sysfs_emit(buf, "%d\n", (int8_t)regval * 1000);
-}
-
-static ssize_t temp_store(struct device *dev, struct device_attribute *attr,
-			  const char *buf, size_t count)
-{
-	struct amc6821_data *data = dev_get_drvdata(dev);
-	int ix = to_sensor_dev_attr(attr)->index;
-	long val;
-	int err;
-
-	int ret = kstrtol(buf, 10, &val);
-	if (ret)
-		return ret;
-	val = clamp_val(val / 1000, -128, 127);
-
-	err = regmap_write(data->regmap, temp_reg[ix], val);
-	if (err)
-		return err;
-
-	return count;
-}
-
-static ssize_t temp_alarm_show(struct device *dev,
-			       struct device_attribute *devattr, char *buf)
-{
-	struct amc6821_data *data = dev_get_drvdata(dev);
-	int ix = to_sensor_dev_attr(devattr)->index;
-	u32 regval, mask, reg;
-	int err;
-
-	switch (ix) {
-	case IDX_TEMP1_MIN:
-		reg = AMC6821_REG_STAT1;
-		mask = AMC6821_STAT1_LTL;
+	switch (attr) {
+	case hwmon_temp_input:
+		reg = channel ? AMC6821_REG_RTEMP_HI : AMC6821_REG_LTEMP_HI;
 		break;
-	case IDX_TEMP1_MAX:
-		reg = AMC6821_REG_STAT1;
-		mask = AMC6821_STAT1_LTH;
+	case hwmon_temp_min:
+		reg = channel ? AMC6821_REG_RTEMP_LIMIT_MIN : AMC6821_REG_LTEMP_LIMIT_MIN;
 		break;
-	case IDX_TEMP1_CRIT:
-		reg = AMC6821_REG_STAT2;
-		mask = AMC6821_STAT2_LTC;
+	case hwmon_temp_max:
+		reg = channel ? AMC6821_REG_RTEMP_LIMIT_MAX : AMC6821_REG_LTEMP_LIMIT_MAX;
 		break;
-	case IDX_TEMP2_MIN:
-		reg = AMC6821_REG_STAT1;
-		mask = AMC6821_STAT1_RTL;
-		break;
-	case IDX_TEMP2_MAX:
-		reg = AMC6821_REG_STAT1;
-		mask = AMC6821_STAT1_RTH;
-		break;
-	case IDX_TEMP2_CRIT:
-		reg = AMC6821_REG_STAT2;
-		mask = AMC6821_STAT2_RTC;
+	case hwmon_temp_crit:
+		reg = channel ? AMC6821_REG_RTEMP_CRIT : AMC6821_REG_LTEMP_CRIT;
 		break;
 	default:
-		dev_dbg(dev, "Unknown attr->index (%d).\n", ix);
-		return -EINVAL;
+		return -EOPNOTSUPP;
 	}
-	err = regmap_read(data->regmap, reg, &regval);
+	err = regmap_read(regmap, reg, &regval);
 	if (err)
 		return err;
-	return sysfs_emit(buf, "%d\n", !!(regval & mask));
+	*val = (int8_t)regval * 1000;
+	return 0;
 }
 
-static ssize_t temp2_fault_show(struct device *dev,
-				struct device_attribute *devattr, char *buf)
+static int amc6821_read_alarms(struct regmap *regmap, enum hwmon_sensor_types type,
+			       u32 attr, int channel, long *val)
 {
-	struct amc6821_data *data = dev_get_drvdata(dev);
+	int reg, mask, err;
 	u32 regval;
-	int err;
 
-	err = regmap_read(data->regmap, AMC6821_REG_STAT1, &regval);
-	if (err)
-		return err;
-
-	return sysfs_emit(buf, "%d\n", !!(regval & AMC6821_STAT1_RTF));
-}
-
-static ssize_t pwm1_show(struct device *dev, struct device_attribute *devattr,
-			 char *buf)
-{
-	struct amc6821_data *data = dev_get_drvdata(dev);
-	u32 regval;
-	int err;
-
-	err = regmap_read(data->regmap, AMC6821_REG_DCY, &regval);
-	if (err)
-		return err;
-
-	return sysfs_emit(buf, "%d\n", regval);
-}
-
-static ssize_t pwm1_store(struct device *dev,
-			  struct device_attribute *devattr, const char *buf,
-			  size_t count)
-{
-	struct amc6821_data *data = dev_get_drvdata(dev);
-	long val;
-	int ret = kstrtol(buf, 10, &val);
-	if (ret)
-		return ret;
-
-	if (val < 0 || val > 255)
-		return -EINVAL;
-
-	ret = regmap_write(data->regmap, AMC6821_REG_DCY, val);
-	if (ret)
-		return ret;
-
-	return count;
-}
-
-static ssize_t pwm1_enable_show(struct device *dev,
-				struct device_attribute *devattr, char *buf)
-{
-	struct amc6821_data *data = dev_get_drvdata(dev);
-	int err;
-	u32 val;
-
-	err = regmap_read(data->regmap, AMC6821_REG_CONF1, &val);
-	if (err)
-		return err;
-	switch (val & (AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1)) {
-	case 0:
-		val = 1;	/* manual */
+	switch (type) {
+	case hwmon_temp:
+		switch (attr) {
+		case hwmon_temp_min_alarm:
+			reg = AMC6821_REG_STAT1;
+			mask = channel ? AMC6821_STAT1_RTL : AMC6821_STAT1_LTL;
+			break;
+		case hwmon_temp_max_alarm:
+			reg = AMC6821_REG_STAT1;
+			mask = channel ? AMC6821_STAT1_RTH : AMC6821_STAT1_LTH;
+			break;
+		case hwmon_temp_crit_alarm:
+			reg = AMC6821_REG_STAT2;
+			mask = channel ? AMC6821_STAT2_RTC : AMC6821_STAT2_LTC;
+			break;
+		case hwmon_temp_fault:
+			reg = AMC6821_REG_STAT1;
+			mask = AMC6821_STAT1_RTF;
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
 		break;
-	case AMC6821_CONF1_FDRC0:
-		val = 4;	/* target rpm (fan1_target) controlled */
-		break;
-	case AMC6821_CONF1_FDRC1:
-		val = 2;	/* remote temp controlled */
+	case hwmon_fan:
+		switch (attr) {
+		case hwmon_fan_fault:
+			reg = AMC6821_REG_STAT1;
+			mask = AMC6821_STAT1_FANS;
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
 		break;
 	default:
-		val = 3;	/* max(local, remote) temp controlled */
-		break;
+		return -EOPNOTSUPP;
 	}
-	return sysfs_emit(buf, "%d\n", val);
+	err = regmap_read(regmap, reg, &regval);
+	if (err)
+		return err;
+	*val = !!(regval & mask);
+	return 0;
 }
 
-static ssize_t pwm1_enable_store(struct device *dev,
-				 struct device_attribute *attr,
-				 const char *buf, size_t count)
+static int amc6821_temp_read(struct device *dev, u32 attr, int channel, long *val)
 {
 	struct amc6821_data *data = dev_get_drvdata(dev);
-	long val;
+
+	switch (attr) {
+	case hwmon_temp_input:
+	case hwmon_temp_min:
+	case hwmon_temp_max:
+	case hwmon_temp_crit:
+		return amc6821_temp_read_values(data->regmap, attr, channel, val);
+	case hwmon_temp_min_alarm:
+	case hwmon_temp_max_alarm:
+	case hwmon_temp_crit_alarm:
+	case hwmon_temp_fault:
+		return amc6821_read_alarms(data->regmap, hwmon_temp, attr, channel, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int amc6821_temp_write(struct device *dev, u32 attr, int channel, long val)
+{
+	struct amc6821_data *data = dev_get_drvdata(dev);
+	int reg;
+
+	val = DIV_ROUND_CLOSEST(clamp_val(val, -128000, 127000), 1000);
+
+	switch (attr) {
+	case hwmon_temp_min:
+		reg = channel ? AMC6821_REG_RTEMP_LIMIT_MIN : AMC6821_REG_LTEMP_LIMIT_MIN;
+		break;
+	case hwmon_temp_max:
+		reg = channel ? AMC6821_REG_RTEMP_LIMIT_MAX : AMC6821_REG_LTEMP_LIMIT_MAX;
+		break;
+	case hwmon_temp_crit:
+		reg = channel ? AMC6821_REG_RTEMP_CRIT : AMC6821_REG_LTEMP_CRIT;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+	return regmap_write(data->regmap, reg, val);
+}
+
+static int amc6821_pwm_read(struct device *dev, u32 attr, long *val)
+{
+	struct amc6821_data *data = dev_get_drvdata(dev);
+	struct regmap *regmap = data->regmap;
+	u32 regval;
+	int err;
+
+	switch (attr) {
+	case hwmon_pwm_enable:
+		err = regmap_read(regmap, AMC6821_REG_CONF1, &regval);
+		if (err)
+			return err;
+		switch (regval & (AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1)) {
+		case 0:
+			*val = 1;	/* manual */
+			break;
+		case AMC6821_CONF1_FDRC0:
+			*val = 4;	/* target rpm (fan1_target) controlled */
+			break;
+		case AMC6821_CONF1_FDRC1:
+			*val = 2;	/* remote temp controlled */
+			break;
+		default:
+			*val = 3;	/* max(local, remote) temp controlled */
+			break;
+		}
+		return 0;
+	case hwmon_pwm_auto_channels_temp:
+		err = regmap_read(regmap, AMC6821_REG_CONF1, &regval);
+		if (err)
+			return err;
+		switch (regval & (AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1)) {
+		case 0:
+		case AMC6821_CONF1_FDRC0:
+			*val = 0;	/* manual or target rpm controlled */
+			break;
+		case AMC6821_CONF1_FDRC1:
+			*val = 2;	/* remote temp controlled */
+			break;
+		default:
+			*val = 3;	/* max(local, remote) temp controlled */
+			break;
+		}
+		return 0;
+	case hwmon_pwm_input:
+		err = regmap_read(regmap, AMC6821_REG_DCY, &regval);
+		if (err)
+			return err;
+		*val = regval;
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int amc6821_pwm_write(struct device *dev, u32 attr, long val)
+{
+	struct amc6821_data *data = dev_get_drvdata(dev);
+	struct regmap *regmap = data->regmap;
 	u32 mask;
-	int err;
 
-	err = kstrtol(buf, 10, &val);
-	if (err)
-		return err;
-
-	switch (val) {
-	case 1:
-		mask = 0;
-		break;
-	case 2:
-		mask = AMC6821_CONF1_FDRC1;
-		break;
-	case 3:
-		mask = AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1;
-		break;
-	case 4:
-		mask = AMC6821_CONF1_FDRC0;
-		break;
+	switch (attr) {
+	case hwmon_pwm_enable:
+		switch (val) {
+		case 1:
+			mask = 0;
+			break;
+		case 2:
+			mask = AMC6821_CONF1_FDRC1;
+			break;
+		case 3:
+			mask = AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1;
+			break;
+		case 4:
+			mask = AMC6821_CONF1_FDRC0;
+			break;
+		default:
+			return -EINVAL;
+		}
+		return regmap_update_bits(regmap, AMC6821_REG_CONF1,
+					  AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1,
+					  mask);
+	case hwmon_pwm_input:
+		if (val < 0 || val > 255)
+			return -EINVAL;
+		return regmap_write(regmap, AMC6821_REG_DCY, val);
 	default:
-		return -EINVAL;
+		return -EOPNOTSUPP;
 	}
-
-	err = regmap_update_bits(data->regmap, AMC6821_REG_CONF1,
-				 AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1,
-				 mask);
-	if (err < 0)
-		return err;
-
-	return count;
 }
 
-static ssize_t pwm1_auto_channels_temp_show(struct device *dev,
-					    struct device_attribute *devattr,
-					    char *buf)
+static int amc6821_fan_read_rpm(struct regmap *regmap, u32 attr, long *val)
 {
-	struct amc6821_data *data = dev_get_drvdata(dev);
-	u32 val;
-	int err;
+	int reg, err;
+	u8 regs[2];
+	u32 regval;
 
-	err = regmap_read(data->regmap, AMC6821_REG_CONF1, &val);
-	if (err)
-		return err;
-	switch (val & (AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1)) {
-	case 0:
-	case AMC6821_CONF1_FDRC0:
-		val = 0;	/* manual or target rpm controlled */
+	switch (attr) {
+	case hwmon_fan_input:
+		reg = AMC6821_REG_TDATA_LOW;
 		break;
-	case AMC6821_CONF1_FDRC1:
-		val = 2;	/* remote temp controlled */
+	case hwmon_fan_min:
+		reg = AMC6821_REG_TACH_LLIMITL;
+		break;
+	case hwmon_fan_max:
+		reg = AMC6821_REG_TACH_HLIMITL;
+		break;
+	case hwmon_fan_target:
+		reg = AMC6821_REG_TACH_SETTINGL;
 		break;
 	default:
-		val = 3;	/* max(local, remote) temp controlled */
-		break;
+		return -EOPNOTSUPP;
 	}
 
-	return sprintf(buf, "%d\n", val);
+	err = regmap_bulk_read(regmap, reg, regs, 2);
+	if (err)
+		return err;
+
+	regval = (regs[1] << 8) | regs[0];
+	*val = 6000000 / (regval ? : 1);
+
+	return 0;
+}
+
+static int amc6821_fan_read(struct device *dev, u32 attr, long *val)
+{
+	struct amc6821_data *data = dev_get_drvdata(dev);
+	struct regmap *regmap = data->regmap;
+	u32 regval;
+	int err;
+
+	switch (attr) {
+	case hwmon_fan_input:
+	case hwmon_fan_min:
+	case hwmon_fan_max:
+	case hwmon_fan_target:
+		return amc6821_fan_read_rpm(regmap, attr, val);
+	case hwmon_fan_fault:
+		return amc6821_read_alarms(regmap, hwmon_fan, attr, 0, val);
+	case hwmon_fan_pulses:
+		err = regmap_read(regmap, AMC6821_REG_CONF4, &regval);
+		if (err)
+			return err;
+		*val = (regval & AMC6821_CONF4_PSPR) ? 4 : 2;
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int amc6821_fan_write(struct device *dev, u32 attr, long val)
+{
+	struct amc6821_data *data = dev_get_drvdata(dev);
+	struct regmap *regmap = data->regmap;
+	u8 regs[2];
+	int reg;
+
+	if (attr == hwmon_fan_pulses) {
+		if (val != 2 && val != 4)
+			return -EINVAL;
+		return regmap_update_bits(regmap, AMC6821_REG_CONF4,
+					 AMC6821_CONF4_PSPR,
+					 val == 4 ? AMC6821_CONF4_PSPR : 0);
+	}
+
+	if (val < 0)
+		return -EINVAL;
+
+	val = clamp_val(6000000 / (val ? : 1), 0, 0xffff);
+
+	switch (attr) {
+	case hwmon_fan_min:
+		reg = AMC6821_REG_TACH_LLIMITL;
+		break;
+	case hwmon_fan_max:
+		reg = AMC6821_REG_TACH_HLIMITL;
+		break;
+	case hwmon_fan_target:
+		reg = AMC6821_REG_TACH_SETTINGL;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	regs[0] = val & 0xff;
+	regs[1] = val >> 8;
+
+	return regmap_bulk_write(data->regmap, reg, regs, 2);
 }
 
 static ssize_t temp_auto_point_temp_show(struct device *dev,
 					 struct device_attribute *devattr,
 					 char *buf)
 {
+	struct amc6821_data *data = dev_get_drvdata(dev);
 	int ix = to_sensor_dev_attr_2(devattr)->index;
 	int nr = to_sensor_dev_attr_2(devattr)->nr;
-	struct amc6821_data *data = dev_get_drvdata(dev);
 
 	switch (nr) {
 	case 1:
@@ -423,7 +495,6 @@ static ssize_t temp_auto_point_temp_show(struct device *dev,
 		return sprintf(buf, "%d\n",
 			data->temp2_auto_point_temp[ix] * 1000);
 	default:
-		dev_dbg(dev, "Unknown attr->nr (%d).\n", nr);
 		return -EINVAL;
 	}
 }
@@ -579,130 +650,9 @@ static ssize_t pwm1_auto_point_pwm_store(struct device *dev,
 	return count;
 }
 
-static ssize_t fan_show(struct device *dev, struct device_attribute *devattr,
-			char *buf)
-{
-	struct amc6821_data *data = dev_get_drvdata(dev);
-	int ix = to_sensor_dev_attr(devattr)->index;
-	u32 regval;
-	u8 regs[2];
-	int err;
-
-	err = regmap_bulk_read(data->regmap, fan_reg_low[ix], regs, 2);
-	if (err)
-		return err;
-	regval = (regs[1] << 8) | regs[0];
-
-	return sysfs_emit(buf, "%d\n", 6000000 / (regval ? : 1));
-}
-
-static ssize_t fan1_fault_show(struct device *dev,
-			       struct device_attribute *devattr, char *buf)
-{
-	struct amc6821_data *data = dev_get_drvdata(dev);
-	u32 regval;
-	int err;
-
-	err = regmap_read(data->regmap, AMC6821_REG_STAT1, &regval);
-	if (err)
-		return err;
-
-	return sysfs_emit(buf, "%d\n", !!(regval & AMC6821_STAT1_FANS));
-}
-
-static ssize_t fan_store(struct device *dev, struct device_attribute *attr,
-			 const char *buf, size_t count)
-{
-	struct amc6821_data *data = dev_get_drvdata(dev);
-	int ix = to_sensor_dev_attr(attr)->index;
-	u8 regs[2];
-	long val;
-	int err;
-
-	err = kstrtol(buf, 10, &val);
-	if (err)
-		return err;
-
-	val = val < 1 ? 0xFFFF : 6000000 / val;
-	val = clamp_val(val, 0, 0xFFFF);
-
-	regs[0] = val & 0xff;
-	regs[1] = val >> 8;
-
-	err = regmap_bulk_write(data->regmap, fan_reg_low[ix], regs, 2);
-	if (err)
-		return err;
-
-	return count;
-}
-
-static ssize_t fan1_pulses_show(struct device *dev,
-				struct device_attribute *devattr, char *buf)
-{
-	struct amc6821_data *data = dev_get_drvdata(dev);
-	u32 regval;
-	int err;
-
-	err = regmap_read(data->regmap, AMC6821_REG_CONF4, &regval);
-	if (err)
-		return err;
-
-	return sysfs_emit(buf, "%d\n", (regval & AMC6821_CONF4_PSPR) ? 4 : 2);
-}
-
-static ssize_t fan1_pulses_store(struct device *dev,
-				 struct device_attribute *attr, const char *buf,
-				 size_t count)
-{
-	struct amc6821_data *data = dev_get_drvdata(dev);
-	long val;
-	int err;
-
-	err = kstrtol(buf, 10, &val);
-	if (err)
-		return err;
-
-	if (val != 2 && val != 4)
-		return -EINVAL;
-
-	err = regmap_update_bits(data->regmap, AMC6821_REG_CONF4,
-				 AMC6821_CONF4_PSPR,
-				 val == 4 ? AMC6821_CONF4_PSPR : 0);
-	if (err)
-		return err;
-
-	return count;
-}
-
-static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, IDX_TEMP1_INPUT);
-static SENSOR_DEVICE_ATTR_RW(temp1_min, temp, IDX_TEMP1_MIN);
-static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, IDX_TEMP1_MAX);
-static SENSOR_DEVICE_ATTR_RW(temp1_crit, temp, IDX_TEMP1_CRIT);
-static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, temp_alarm, IDX_TEMP1_MIN);
-static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, temp_alarm, IDX_TEMP1_MAX);
-static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, temp_alarm, IDX_TEMP1_CRIT);
-static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, IDX_TEMP2_INPUT);
-static SENSOR_DEVICE_ATTR_RW(temp2_min, temp, IDX_TEMP2_MIN);
-static SENSOR_DEVICE_ATTR_RW(temp2_max, temp, IDX_TEMP2_MAX);
-static SENSOR_DEVICE_ATTR_RW(temp2_crit, temp, IDX_TEMP2_CRIT);
-static SENSOR_DEVICE_ATTR_RO(temp2_fault, temp2_fault, 0);
-static SENSOR_DEVICE_ATTR_RO(temp2_min_alarm, temp_alarm, IDX_TEMP2_MIN);
-static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, temp_alarm, IDX_TEMP2_MAX);
-static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, temp_alarm, IDX_TEMP2_CRIT);
-static SENSOR_DEVICE_ATTR_RO(fan1_input, fan, IDX_FAN1_INPUT);
-static SENSOR_DEVICE_ATTR_RW(fan1_min, fan, IDX_FAN1_MIN);
-static SENSOR_DEVICE_ATTR_RW(fan1_max, fan, IDX_FAN1_MAX);
-static SENSOR_DEVICE_ATTR_RW(fan1_target, fan, IDX_FAN1_TARGET);
-static SENSOR_DEVICE_ATTR_RO(fan1_fault, fan1_fault, 0);
-static SENSOR_DEVICE_ATTR_RW(fan1_pulses, fan1_pulses, 0);
-
-static SENSOR_DEVICE_ATTR_RW(pwm1, pwm1, 0);
-static SENSOR_DEVICE_ATTR_RW(pwm1_enable, pwm1_enable, 0);
 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point1_pwm, pwm1_auto_point_pwm, 0);
 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point2_pwm, pwm1_auto_point_pwm, 1);
 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point3_pwm, pwm1_auto_point_pwm, 2);
-static SENSOR_DEVICE_ATTR_RO(pwm1_auto_channels_temp, pwm1_auto_channels_temp,
-			     0);
 static SENSOR_DEVICE_ATTR_2_RO(temp1_auto_point1_temp, temp_auto_point_temp,
 			       1, 0);
 static SENSOR_DEVICE_ATTR_2_RW(temp1_auto_point2_temp, temp_auto_point_temp,
@@ -718,30 +668,6 @@ static SENSOR_DEVICE_ATTR_2_RW(temp2_auto_point3_temp, temp_auto_point_temp,
 			       2, 2);
 
 static struct attribute *amc6821_attrs[] = {
-	&sensor_dev_attr_temp1_input.dev_attr.attr,
-	&sensor_dev_attr_temp1_min.dev_attr.attr,
-	&sensor_dev_attr_temp1_max.dev_attr.attr,
-	&sensor_dev_attr_temp1_crit.dev_attr.attr,
-	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
-	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
-	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
-	&sensor_dev_attr_temp2_input.dev_attr.attr,
-	&sensor_dev_attr_temp2_min.dev_attr.attr,
-	&sensor_dev_attr_temp2_max.dev_attr.attr,
-	&sensor_dev_attr_temp2_crit.dev_attr.attr,
-	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
-	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
-	&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
-	&sensor_dev_attr_temp2_fault.dev_attr.attr,
-	&sensor_dev_attr_fan1_input.dev_attr.attr,
-	&sensor_dev_attr_fan1_min.dev_attr.attr,
-	&sensor_dev_attr_fan1_max.dev_attr.attr,
-	&sensor_dev_attr_fan1_target.dev_attr.attr,
-	&sensor_dev_attr_fan1_fault.dev_attr.attr,
-	&sensor_dev_attr_fan1_pulses.dev_attr.attr,
-	&sensor_dev_attr_pwm1.dev_attr.attr,
-	&sensor_dev_attr_pwm1_enable.dev_attr.attr,
-	&sensor_dev_attr_pwm1_auto_channels_temp.dev_attr.attr,
 	&sensor_dev_attr_pwm1_auto_point1_pwm.dev_attr.attr,
 	&sensor_dev_attr_pwm1_auto_point2_pwm.dev_attr.attr,
 	&sensor_dev_attr_pwm1_auto_point3_pwm.dev_attr.attr,
@@ -753,13 +679,117 @@ static struct attribute *amc6821_attrs[] = {
 	&sensor_dev_attr_temp2_auto_point3_temp.dev_attr.attr,
 	NULL
 };
-
 ATTRIBUTE_GROUPS(amc6821);
 
+static int amc6821_read(struct device *dev, enum hwmon_sensor_types type,
+			u32 attr, int channel, long *val)
+{
+	switch (type) {
+	case hwmon_temp:
+		return amc6821_temp_read(dev, attr, channel, val);
+	case hwmon_fan:
+		return amc6821_fan_read(dev, attr, val);
+	case hwmon_pwm:
+		return amc6821_pwm_read(dev, attr, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int amc6821_write(struct device *dev, enum hwmon_sensor_types type,
+			 u32 attr, int channel, long val)
+{
+	switch (type) {
+	case hwmon_temp:
+		return amc6821_temp_write(dev, attr, channel, val);
+	case hwmon_fan:
+		return amc6821_fan_write(dev, attr, val);
+	case hwmon_pwm:
+		return amc6821_pwm_write(dev, attr, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static umode_t amc6821_is_visible(const void *data,
+				  enum hwmon_sensor_types type,
+				  u32 attr, int channel)
+{
+	switch (type) {
+	case hwmon_temp:
+		switch (attr) {
+		case hwmon_temp_input:
+		case hwmon_temp_min_alarm:
+		case hwmon_temp_max_alarm:
+		case hwmon_temp_crit_alarm:
+		case hwmon_temp_fault:
+			return 0444;
+		case hwmon_temp_min:
+		case hwmon_temp_max:
+		case hwmon_temp_crit:
+			return 0644;
+		default:
+			return 0;
+		}
+	case hwmon_fan:
+		switch (attr) {
+		case hwmon_fan_input:
+		case hwmon_fan_fault:
+			return 0444;
+		case hwmon_fan_pulses:
+		case hwmon_fan_min:
+		case hwmon_fan_max:
+		case hwmon_fan_target:
+			return 0644;
+		default:
+			return 0;
+		}
+	case hwmon_pwm:
+		switch (attr) {
+		case hwmon_pwm_enable:
+		case hwmon_pwm_input:
+			return 0644;
+		case hwmon_pwm_auto_channels_temp:
+			return 0444;
+		default:
+			return 0;
+		}
+	default:
+		return 0;
+	}
+}
+
+static const struct hwmon_channel_info * const amc6821_info[] = {
+	HWMON_CHANNEL_INFO(temp,
+			   HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
+			   HWMON_T_CRIT | HWMON_T_MIN_ALARM |
+			   HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM,
+			   HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
+			   HWMON_T_CRIT | HWMON_T_MIN_ALARM |
+			   HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM |
+			   HWMON_T_FAULT),
+	HWMON_CHANNEL_INFO(fan,
+			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_MAX |
+			   HWMON_F_TARGET | HWMON_F_PULSES | HWMON_F_FAULT),
+	HWMON_CHANNEL_INFO(pwm,
+			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE |
+			   HWMON_PWM_AUTO_CHANNELS_TEMP),
+	NULL
+};
+
+static const struct hwmon_ops amc6821_hwmon_ops = {
+	.is_visible = amc6821_is_visible,
+	.read = amc6821_read,
+	.write = amc6821_write,
+};
+
+static const struct hwmon_chip_info amc6821_chip_info = {
+	.ops = &amc6821_hwmon_ops,
+	.info = amc6821_info,
+};
+
 /* Return 0 if detection is successful, -ENODEV otherwise */
-static int amc6821_detect(
-		struct i2c_client *client,
-		struct i2c_board_info *info)
+static int amc6821_detect(struct i2c_client *client, struct i2c_board_info *info)
 {
 	struct i2c_adapter *adapter = client->adapter;
 	int address = client->addr;
@@ -872,7 +902,6 @@ static int amc6821_probe(struct i2c_client *client)
 	if (!data)
 		return -ENOMEM;
 
-
 	regmap = devm_regmap_init_i2c(client, &amc6821_regmap_config);
 	if (IS_ERR(regmap))
 		return dev_err_probe(dev, PTR_ERR(regmap),
@@ -883,9 +912,9 @@ static int amc6821_probe(struct i2c_client *client)
 	if (err)
 		return err;
 
-	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
-							   data,
-							   amc6821_groups);
+	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
+							 data, &amc6821_chip_info,
+							 amc6821_groups);
 	return PTR_ERR_OR_ZERO(hwmon_dev);
 }
 
-- 
2.39.2

Hi Guenter,

On 6/28/24 5:13 PM, Guenter Roeck wrote:
> Convert to use with_info API to simplify the code and make it easier
> to maintain. This also reduces code size by approximately 20%.
> 
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> ---
>   drivers/hwmon/amc6821.c | 743 +++++++++++++++++++++-------------------
>   1 file changed, 386 insertions(+), 357 deletions(-)
> 
> diff --git a/drivers/hwmon/amc6821.c b/drivers/hwmon/amc6821.c
> index 6ffab4288134..14d59aa4254b 100644
> --- a/drivers/hwmon/amc6821.c
> +++ b/drivers/hwmon/amc6821.c
> @@ -6,6 +6,9 @@
>    *
>    * Based on max6650.c:
>    * Copyright (C) 2007 Hans J. Koch <hjk@hansjkoch.de>
> + *
> + * Conversion to regmap and with_info API:
> + * Copyright (C) 2024 Guenter Roeck <linux@roeck-us.net>
>    */
>   
>   #include <linux/bits.h>
> @@ -106,28 +109,6 @@ module_param(init, int, 0444);
>   #define AMC6821_STAT2_L_THERM		BIT(6)
>   #define AMC6821_STAT2_THERM_IN		BIT(7)
>   
> -enum {IDX_TEMP1_INPUT = 0, IDX_TEMP1_MIN, IDX_TEMP1_MAX,
> -	IDX_TEMP1_CRIT, IDX_TEMP2_INPUT, IDX_TEMP2_MIN,
> -	IDX_TEMP2_MAX, IDX_TEMP2_CRIT,
> -	TEMP_IDX_LEN, };
> -
> -static const u8 temp_reg[] = {AMC6821_REG_LTEMP_HI,
> -			AMC6821_REG_LTEMP_LIMIT_MIN,
> -			AMC6821_REG_LTEMP_LIMIT_MAX,
> -			AMC6821_REG_LTEMP_CRIT,
> -			AMC6821_REG_RTEMP_HI,
> -			AMC6821_REG_RTEMP_LIMIT_MIN,
> -			AMC6821_REG_RTEMP_LIMIT_MAX,
> -			AMC6821_REG_RTEMP_CRIT, };
> -
> -enum {IDX_FAN1_INPUT = 0, IDX_FAN1_MIN, IDX_FAN1_MAX, IDX_FAN1_TARGET,
> -	FAN1_IDX_LEN, };
> -
> -static const u8 fan_reg_low[] = {AMC6821_REG_TDATA_LOW,
> -			AMC6821_REG_TACH_LLIMITL,
> -			AMC6821_REG_TACH_HLIMITL,
> -			AMC6821_REG_TACH_SETTINGL, };
> -
>   /*
>    * Client data (each client gets its own)
>    */
> @@ -188,232 +169,323 @@ static int amc6821_init_auto_point_data(struct amc6821_data *data)
>   	return 0;
>   }
>   
> -static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
> -			 char *buf)
> +static int amc6821_temp_read_values(struct regmap *regmap, u32 attr, int channel, long *val)
>   {
> -	struct amc6821_data *data = dev_get_drvdata(dev);
> -	int ix = to_sensor_dev_attr(devattr)->index;
> +	int reg, err;
>   	u32 regval;
> -	int err;
>   
> -	err = regmap_read(data->regmap, temp_reg[ix], &regval);
> -	if (err)
> -		return err;
> -
> -	return sysfs_emit(buf, "%d\n", (int8_t)regval * 1000);
> -}
> -
> -static ssize_t temp_store(struct device *dev, struct device_attribute *attr,
> -			  const char *buf, size_t count)
> -{
> -	struct amc6821_data *data = dev_get_drvdata(dev);
> -	int ix = to_sensor_dev_attr(attr)->index;
> -	long val;
> -	int err;
> -
> -	int ret = kstrtol(buf, 10, &val);
> -	if (ret)
> -		return ret;
> -	val = clamp_val(val / 1000, -128, 127);
> -
> -	err = regmap_write(data->regmap, temp_reg[ix], val);
> -	if (err)
> -		return err;
> -
> -	return count;
> -}
> -
> -static ssize_t temp_alarm_show(struct device *dev,
> -			       struct device_attribute *devattr, char *buf)
> -{
> -	struct amc6821_data *data = dev_get_drvdata(dev);
> -	int ix = to_sensor_dev_attr(devattr)->index;
> -	u32 regval, mask, reg;
> -	int err;
> -
> -	switch (ix) {
> -	case IDX_TEMP1_MIN:
> -		reg = AMC6821_REG_STAT1;
> -		mask = AMC6821_STAT1_LTL;
> +	switch (attr) {
> +	case hwmon_temp_input:
> +		reg = channel ? AMC6821_REG_RTEMP_HI : AMC6821_REG_LTEMP_HI;
>   		break;
> -	case IDX_TEMP1_MAX:
> -		reg = AMC6821_REG_STAT1;
> -		mask = AMC6821_STAT1_LTH;
> +	case hwmon_temp_min:
> +		reg = channel ? AMC6821_REG_RTEMP_LIMIT_MIN : AMC6821_REG_LTEMP_LIMIT_MIN;
>   		break;
> -	case IDX_TEMP1_CRIT:
> -		reg = AMC6821_REG_STAT2;
> -		mask = AMC6821_STAT2_LTC;
> +	case hwmon_temp_max:
> +		reg = channel ? AMC6821_REG_RTEMP_LIMIT_MAX : AMC6821_REG_LTEMP_LIMIT_MAX;
>   		break;
> -	case IDX_TEMP2_MIN:
> -		reg = AMC6821_REG_STAT1;
> -		mask = AMC6821_STAT1_RTL;
> -		break;
> -	case IDX_TEMP2_MAX:
> -		reg = AMC6821_REG_STAT1;
> -		mask = AMC6821_STAT1_RTH;
> -		break;
> -	case IDX_TEMP2_CRIT:
> -		reg = AMC6821_REG_STAT2;
> -		mask = AMC6821_STAT2_RTC;
> +	case hwmon_temp_crit:
> +		reg = channel ? AMC6821_REG_RTEMP_CRIT : AMC6821_REG_LTEMP_CRIT;
>   		break;
>   	default:
> -		dev_dbg(dev, "Unknown attr->index (%d).\n", ix);
> -		return -EINVAL;
> +		return -EOPNOTSUPP;
>   	}
> -	err = regmap_read(data->regmap, reg, &regval);
> +	err = regmap_read(regmap, reg, &regval);
>   	if (err)
>   		return err;
> -	return sysfs_emit(buf, "%d\n", !!(regval & mask));
> +	*val = (int8_t)regval * 1000;

The discussed signed_extended32() in another patch would need to make it 
here too.

> +	return 0;
>   }
>   
> -static ssize_t temp2_fault_show(struct device *dev,
> -				struct device_attribute *devattr, char *buf)
> +static int amc6821_read_alarms(struct regmap *regmap, enum hwmon_sensor_types type,
> +			       u32 attr, int channel, long *val)
>   {
> -	struct amc6821_data *data = dev_get_drvdata(dev);
> +	int reg, mask, err;
>   	u32 regval;
> -	int err;
>   
> -	err = regmap_read(data->regmap, AMC6821_REG_STAT1, &regval);
> -	if (err)
> -		return err;
> -
> -	return sysfs_emit(buf, "%d\n", !!(regval & AMC6821_STAT1_RTF));
> -}
> -
> -static ssize_t pwm1_show(struct device *dev, struct device_attribute *devattr,
> -			 char *buf)
> -{
> -	struct amc6821_data *data = dev_get_drvdata(dev);
> -	u32 regval;
> -	int err;
> -
> -	err = regmap_read(data->regmap, AMC6821_REG_DCY, &regval);
> -	if (err)
> -		return err;
> -
> -	return sysfs_emit(buf, "%d\n", regval);
> -}
> -
> -static ssize_t pwm1_store(struct device *dev,
> -			  struct device_attribute *devattr, const char *buf,
> -			  size_t count)
> -{
> -	struct amc6821_data *data = dev_get_drvdata(dev);
> -	long val;
> -	int ret = kstrtol(buf, 10, &val);
> -	if (ret)
> -		return ret;
> -
> -	if (val < 0 || val > 255)
> -		return -EINVAL;
> -
> -	ret = regmap_write(data->regmap, AMC6821_REG_DCY, val);
> -	if (ret)
> -		return ret;
> -
> -	return count;
> -}
> -
> -static ssize_t pwm1_enable_show(struct device *dev,
> -				struct device_attribute *devattr, char *buf)
> -{
> -	struct amc6821_data *data = dev_get_drvdata(dev);
> -	int err;
> -	u32 val;
> -
> -	err = regmap_read(data->regmap, AMC6821_REG_CONF1, &val);
> -	if (err)
> -		return err;
> -	switch (val & (AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1)) {
> -	case 0:
> -		val = 1;	/* manual */
> +	switch (type) {
> +	case hwmon_temp:
> +		switch (attr) {
> +		case hwmon_temp_min_alarm:
> +			reg = AMC6821_REG_STAT1;
> +			mask = channel ? AMC6821_STAT1_RTL : AMC6821_STAT1_LTL;
> +			break;
> +		case hwmon_temp_max_alarm:
> +			reg = AMC6821_REG_STAT1;
> +			mask = channel ? AMC6821_STAT1_RTH : AMC6821_STAT1_LTH;
> +			break;
> +		case hwmon_temp_crit_alarm:
> +			reg = AMC6821_REG_STAT2;
> +			mask = channel ? AMC6821_STAT2_RTC : AMC6821_STAT2_LTC;
> +			break;
> +		case hwmon_temp_fault:
> +			reg = AMC6821_REG_STAT1;
> +			mask = AMC6821_STAT1_RTF;
> +			break;
> +		default:
> +			return -EOPNOTSUPP;
> +		}
>   		break;
> -	case AMC6821_CONF1_FDRC0:
> -		val = 4;	/* target rpm (fan1_target) controlled */
> -		break;
> -	case AMC6821_CONF1_FDRC1:
> -		val = 2;	/* remote temp controlled */
> +	case hwmon_fan:
> +		switch (attr) {
> +		case hwmon_fan_fault:
> +			reg = AMC6821_REG_STAT1;
> +			mask = AMC6821_STAT1_FANS;
> +			break;
> +		default:
> +			return -EOPNOTSUPP;
> +		}
>   		break;
>   	default:
> -		val = 3;	/* max(local, remote) temp controlled */
> -		break;
> +		return -EOPNOTSUPP;
>   	}
> -	return sysfs_emit(buf, "%d\n", val);
> +	err = regmap_read(regmap, reg, &regval);
> +	if (err)
> +		return err;
> +	*val = !!(regval & mask);
> +	return 0;
>   }
>   
> -static ssize_t pwm1_enable_store(struct device *dev,
> -				 struct device_attribute *attr,
> -				 const char *buf, size_t count)
> +static int amc6821_temp_read(struct device *dev, u32 attr, int channel, long *val)
>   {
>   	struct amc6821_data *data = dev_get_drvdata(dev);
> -	long val;
> +
> +	switch (attr) {
> +	case hwmon_temp_input:
> +	case hwmon_temp_min:
> +	case hwmon_temp_max:
> +	case hwmon_temp_crit:
> +		return amc6821_temp_read_values(data->regmap, attr, channel, val);
> +	case hwmon_temp_min_alarm:
> +	case hwmon_temp_max_alarm:
> +	case hwmon_temp_crit_alarm:
> +	case hwmon_temp_fault:
> +		return amc6821_read_alarms(data->regmap, hwmon_temp, attr, channel, val);
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +}
> +
> +static int amc6821_temp_write(struct device *dev, u32 attr, int channel, long val)
> +{
> +	struct amc6821_data *data = dev_get_drvdata(dev);
> +	int reg;
> +
> +	val = DIV_ROUND_CLOSEST(clamp_val(val, -128000, 127000), 1000);
> +
> +	switch (attr) {
> +	case hwmon_temp_min:
> +		reg = channel ? AMC6821_REG_RTEMP_LIMIT_MIN : AMC6821_REG_LTEMP_LIMIT_MIN;
> +		break;
> +	case hwmon_temp_max:
> +		reg = channel ? AMC6821_REG_RTEMP_LIMIT_MAX : AMC6821_REG_LTEMP_LIMIT_MAX;
> +		break;
> +	case hwmon_temp_crit:
> +		reg = channel ? AMC6821_REG_RTEMP_CRIT : AMC6821_REG_LTEMP_CRIT;
> +		break;
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +	return regmap_write(data->regmap, reg, val);
> +}
> +
> +static int amc6821_pwm_read(struct device *dev, u32 attr, long *val)
> +{
> +	struct amc6821_data *data = dev_get_drvdata(dev);
> +	struct regmap *regmap = data->regmap;
> +	u32 regval;
> +	int err;
> +
> +	switch (attr) {
> +	case hwmon_pwm_enable:
> +		err = regmap_read(regmap, AMC6821_REG_CONF1, &regval);
> +		if (err)
> +			return err;
> +		switch (regval & (AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1)) {
> +		case 0:
> +			*val = 1;	/* manual */
> +			break;
> +		case AMC6821_CONF1_FDRC0:
> +			*val = 4;	/* target rpm (fan1_target) controlled */
> +			break;
> +		case AMC6821_CONF1_FDRC1:
> +			*val = 2;	/* remote temp controlled */
> +			break;
> +		default:
> +			*val = 3;	/* max(local, remote) temp controlled */
> +			break;
> +		}
> +		return 0;
> +	case hwmon_pwm_auto_channels_temp:
> +		err = regmap_read(regmap, AMC6821_REG_CONF1, &regval);
> +		if (err)
> +			return err;
> +		switch (regval & (AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1)) {
> +		case 0:
> +		case AMC6821_CONF1_FDRC0:
> +			*val = 0;	/* manual or target rpm controlled */
> +			break;
> +		case AMC6821_CONF1_FDRC1:
> +			*val = 2;	/* remote temp controlled */
> +			break;
> +		default:
> +			*val = 3;	/* max(local, remote) temp controlled */
> +			break;
> +		}
> +		return 0;
> +	case hwmon_pwm_input:
> +		err = regmap_read(regmap, AMC6821_REG_DCY, &regval);
> +		if (err)
> +			return err;
> +		*val = regval;
> +		return 0;
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +}
> +
> +static int amc6821_pwm_write(struct device *dev, u32 attr, long val)
> +{
> +	struct amc6821_data *data = dev_get_drvdata(dev);
> +	struct regmap *regmap = data->regmap;
>   	u32 mask;
> -	int err;
>   
> -	err = kstrtol(buf, 10, &val);
> -	if (err)
> -		return err;
> -
> -	switch (val) {
> -	case 1:
> -		mask = 0;
> -		break;
> -	case 2:
> -		mask = AMC6821_CONF1_FDRC1;
> -		break;
> -	case 3:
> -		mask = AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1;
> -		break;
> -	case 4:
> -		mask = AMC6821_CONF1_FDRC0;
> -		break;
> +	switch (attr) {
> +	case hwmon_pwm_enable:
> +		switch (val) {
> +		case 1:
> +			mask = 0;
> +			break;
> +		case 2:
> +			mask = AMC6821_CONF1_FDRC1;
> +			break;
> +		case 3:
> +			mask = AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1;
> +			break;
> +		case 4:
> +			mask = AMC6821_CONF1_FDRC0;
> +			break;
> +		default:
> +			return -EINVAL;
> +		}
> +		return regmap_update_bits(regmap, AMC6821_REG_CONF1,
> +					  AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1,
> +					  mask);
> +	case hwmon_pwm_input:
> +		if (val < 0 || val > 255)
> +			return -EINVAL;
> +		return regmap_write(regmap, AMC6821_REG_DCY, val);
>   	default:
> -		return -EINVAL;
> +		return -EOPNOTSUPP;
>   	}
> -
> -	err = regmap_update_bits(data->regmap, AMC6821_REG_CONF1,
> -				 AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1,
> -				 mask);
> -	if (err < 0)
> -		return err;
> -
> -	return count;
>   }
>   
> -static ssize_t pwm1_auto_channels_temp_show(struct device *dev,
> -					    struct device_attribute *devattr,
> -					    char *buf)
> +static int amc6821_fan_read_rpm(struct regmap *regmap, u32 attr, long *val)
>   {
> -	struct amc6821_data *data = dev_get_drvdata(dev);
> -	u32 val;
> -	int err;
> +	int reg, err;
> +	u8 regs[2];
> +	u32 regval;
>   
> -	err = regmap_read(data->regmap, AMC6821_REG_CONF1, &val);
> -	if (err)
> -		return err;
> -	switch (val & (AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1)) {
> -	case 0:
> -	case AMC6821_CONF1_FDRC0:
> -		val = 0;	/* manual or target rpm controlled */
> +	switch (attr) {
> +	case hwmon_fan_input:
> +		reg = AMC6821_REG_TDATA_LOW;
>   		break;
> -	case AMC6821_CONF1_FDRC1:
> -		val = 2;	/* remote temp controlled */
> +	case hwmon_fan_min:
> +		reg = AMC6821_REG_TACH_LLIMITL;
> +		break;
> +	case hwmon_fan_max:
> +		reg = AMC6821_REG_TACH_HLIMITL;
> +		break;
> +	case hwmon_fan_target:
> +		reg = AMC6821_REG_TACH_SETTINGL;
>   		break;
>   	default:
> -		val = 3;	/* max(local, remote) temp controlled */
> -		break;
> +		return -EOPNOTSUPP;
>   	}
>   
> -	return sprintf(buf, "%d\n", val);
> +	err = regmap_bulk_read(regmap, reg, regs, 2);
> +	if (err)
> +		return err;
> +
> +	regval = (regs[1] << 8) | regs[0];
> +	*val = 6000000 / (regval ? : 1);
> +

Just putting a "bookmark" here since we're having a discussion about 
this logic in another thread for another patch.

Also... missing 0 here between the question mark and the colon?

> +	return 0;
> +}
> +
> +static int amc6821_fan_read(struct device *dev, u32 attr, long *val)
> +{
> +	struct amc6821_data *data = dev_get_drvdata(dev);
> +	struct regmap *regmap = data->regmap;
> +	u32 regval;
> +	int err;
> +
> +	switch (attr) {
> +	case hwmon_fan_input:
> +	case hwmon_fan_min:
> +	case hwmon_fan_max:
> +	case hwmon_fan_target:
> +		return amc6821_fan_read_rpm(regmap, attr, val);
> +	case hwmon_fan_fault:
> +		return amc6821_read_alarms(regmap, hwmon_fan, attr, 0, val);
> +	case hwmon_fan_pulses:
> +		err = regmap_read(regmap, AMC6821_REG_CONF4, &regval);
> +		if (err)
> +			return err;
> +		*val = (regval & AMC6821_CONF4_PSPR) ? 4 : 2;
> +		return 0;
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +}
> +
> +static int amc6821_fan_write(struct device *dev, u32 attr, long val)
> +{
> +	struct amc6821_data *data = dev_get_drvdata(dev);
> +	struct regmap *regmap = data->regmap;
> +	u8 regs[2];
> +	int reg;
> +
> +	if (attr == hwmon_fan_pulses) {
> +		if (val != 2 && val != 4)
> +			return -EINVAL;
> +		return regmap_update_bits(regmap, AMC6821_REG_CONF4,
> +					 AMC6821_CONF4_PSPR,
> +					 val == 4 ? AMC6821_CONF4_PSPR : 0);
> +	}
> +
> +	if (val < 0)
> +		return -EINVAL;
> +
> +	val = clamp_val(6000000 / (val ? : 1), 0, 0xffff);
> +

And another "bookmark" here.

> +	switch (attr) {
> +	case hwmon_fan_min:
> +		reg = AMC6821_REG_TACH_LLIMITL;
> +		break;
> +	case hwmon_fan_max:
> +		reg = AMC6821_REG_TACH_HLIMITL;
> +		break;
> +	case hwmon_fan_target:
> +		reg = AMC6821_REG_TACH_SETTINGL;
> +		break;
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +
> +	regs[0] = val & 0xff;
> +	regs[1] = val >> 8;
> +
> +	return regmap_bulk_write(data->regmap, reg, regs, 2);
>   }
>   
>   static ssize_t temp_auto_point_temp_show(struct device *dev,
>   					 struct device_attribute *devattr,
>   					 char *buf)
>   {
> +	struct amc6821_data *data = dev_get_drvdata(dev);
>   	int ix = to_sensor_dev_attr_2(devattr)->index;
>   	int nr = to_sensor_dev_attr_2(devattr)->nr;
> -	struct amc6821_data *data = dev_get_drvdata(dev);
>   

Should be squashed with the appropriate commit?

>   	switch (nr) {
>   	case 1:
> @@ -423,7 +495,6 @@ static ssize_t temp_auto_point_temp_show(struct device *dev,
>   		return sprintf(buf, "%d\n",
>   			data->temp2_auto_point_temp[ix] * 1000);
>   	default:
> -		dev_dbg(dev, "Unknown attr->nr (%d).\n", nr);

Not sure this is related? Maybe a separate commit?

>   		return -EINVAL;
>   	}
>   }
> @@ -579,130 +650,9 @@ static ssize_t pwm1_auto_point_pwm_store(struct device *dev,
>   	return count;
>   }
>   
> -static ssize_t fan_show(struct device *dev, struct device_attribute *devattr,
> -			char *buf)
> -{
> -	struct amc6821_data *data = dev_get_drvdata(dev);
> -	int ix = to_sensor_dev_attr(devattr)->index;
> -	u32 regval;
> -	u8 regs[2];
> -	int err;
> -
> -	err = regmap_bulk_read(data->regmap, fan_reg_low[ix], regs, 2);
> -	if (err)
> -		return err;
> -	regval = (regs[1] << 8) | regs[0];
> -
> -	return sysfs_emit(buf, "%d\n", 6000000 / (regval ? : 1));
> -}
> -
> -static ssize_t fan1_fault_show(struct device *dev,
> -			       struct device_attribute *devattr, char *buf)
> -{
> -	struct amc6821_data *data = dev_get_drvdata(dev);
> -	u32 regval;
> -	int err;
> -
> -	err = regmap_read(data->regmap, AMC6821_REG_STAT1, &regval);
> -	if (err)
> -		return err;
> -
> -	return sysfs_emit(buf, "%d\n", !!(regval & AMC6821_STAT1_FANS));
> -}
> -
> -static ssize_t fan_store(struct device *dev, struct device_attribute *attr,
> -			 const char *buf, size_t count)
> -{
> -	struct amc6821_data *data = dev_get_drvdata(dev);
> -	int ix = to_sensor_dev_attr(attr)->index;
> -	u8 regs[2];
> -	long val;
> -	int err;
> -
> -	err = kstrtol(buf, 10, &val);
> -	if (err)
> -		return err;
> -
> -	val = val < 1 ? 0xFFFF : 6000000 / val;
> -	val = clamp_val(val, 0, 0xFFFF);
> -
> -	regs[0] = val & 0xff;
> -	regs[1] = val >> 8;
> -
> -	err = regmap_bulk_write(data->regmap, fan_reg_low[ix], regs, 2);
> -	if (err)
> -		return err;
> -
> -	return count;
> -}
> -
> -static ssize_t fan1_pulses_show(struct device *dev,
> -				struct device_attribute *devattr, char *buf)
> -{
> -	struct amc6821_data *data = dev_get_drvdata(dev);
> -	u32 regval;
> -	int err;
> -
> -	err = regmap_read(data->regmap, AMC6821_REG_CONF4, &regval);
> -	if (err)
> -		return err;
> -
> -	return sysfs_emit(buf, "%d\n", (regval & AMC6821_CONF4_PSPR) ? 4 : 2);
> -}
> -
> -static ssize_t fan1_pulses_store(struct device *dev,
> -				 struct device_attribute *attr, const char *buf,
> -				 size_t count)
> -{
> -	struct amc6821_data *data = dev_get_drvdata(dev);
> -	long val;
> -	int err;
> -
> -	err = kstrtol(buf, 10, &val);
> -	if (err)
> -		return err;
> -
> -	if (val != 2 && val != 4)
> -		return -EINVAL;
> -
> -	err = regmap_update_bits(data->regmap, AMC6821_REG_CONF4,
> -				 AMC6821_CONF4_PSPR,
> -				 val == 4 ? AMC6821_CONF4_PSPR : 0);
> -	if (err)
> -		return err;
> -
> -	return count;
> -}
> -
> -static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, IDX_TEMP1_INPUT);
> -static SENSOR_DEVICE_ATTR_RW(temp1_min, temp, IDX_TEMP1_MIN);
> -static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, IDX_TEMP1_MAX);
> -static SENSOR_DEVICE_ATTR_RW(temp1_crit, temp, IDX_TEMP1_CRIT);
> -static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, temp_alarm, IDX_TEMP1_MIN);
> -static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, temp_alarm, IDX_TEMP1_MAX);
> -static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, temp_alarm, IDX_TEMP1_CRIT);
> -static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, IDX_TEMP2_INPUT);
> -static SENSOR_DEVICE_ATTR_RW(temp2_min, temp, IDX_TEMP2_MIN);
> -static SENSOR_DEVICE_ATTR_RW(temp2_max, temp, IDX_TEMP2_MAX);
> -static SENSOR_DEVICE_ATTR_RW(temp2_crit, temp, IDX_TEMP2_CRIT);
> -static SENSOR_DEVICE_ATTR_RO(temp2_fault, temp2_fault, 0);
> -static SENSOR_DEVICE_ATTR_RO(temp2_min_alarm, temp_alarm, IDX_TEMP2_MIN);
> -static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, temp_alarm, IDX_TEMP2_MAX);
> -static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, temp_alarm, IDX_TEMP2_CRIT);
> -static SENSOR_DEVICE_ATTR_RO(fan1_input, fan, IDX_FAN1_INPUT);
> -static SENSOR_DEVICE_ATTR_RW(fan1_min, fan, IDX_FAN1_MIN);
> -static SENSOR_DEVICE_ATTR_RW(fan1_max, fan, IDX_FAN1_MAX);
> -static SENSOR_DEVICE_ATTR_RW(fan1_target, fan, IDX_FAN1_TARGET);
> -static SENSOR_DEVICE_ATTR_RO(fan1_fault, fan1_fault, 0);
> -static SENSOR_DEVICE_ATTR_RW(fan1_pulses, fan1_pulses, 0);
> -
> -static SENSOR_DEVICE_ATTR_RW(pwm1, pwm1, 0);
> -static SENSOR_DEVICE_ATTR_RW(pwm1_enable, pwm1_enable, 0);
>   static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point1_pwm, pwm1_auto_point_pwm, 0);
>   static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point2_pwm, pwm1_auto_point_pwm, 1);
>   static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point3_pwm, pwm1_auto_point_pwm, 2);
> -static SENSOR_DEVICE_ATTR_RO(pwm1_auto_channels_temp, pwm1_auto_channels_temp,
> -			     0);
>   static SENSOR_DEVICE_ATTR_2_RO(temp1_auto_point1_temp, temp_auto_point_temp,
>   			       1, 0);
>   static SENSOR_DEVICE_ATTR_2_RW(temp1_auto_point2_temp, temp_auto_point_temp,
> @@ -718,30 +668,6 @@ static SENSOR_DEVICE_ATTR_2_RW(temp2_auto_point3_temp, temp_auto_point_temp,
>   			       2, 2);
>   
>   static struct attribute *amc6821_attrs[] = {
> -	&sensor_dev_attr_temp1_input.dev_attr.attr,
> -	&sensor_dev_attr_temp1_min.dev_attr.attr,
> -	&sensor_dev_attr_temp1_max.dev_attr.attr,
> -	&sensor_dev_attr_temp1_crit.dev_attr.attr,
> -	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
> -	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
> -	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
> -	&sensor_dev_attr_temp2_input.dev_attr.attr,
> -	&sensor_dev_attr_temp2_min.dev_attr.attr,
> -	&sensor_dev_attr_temp2_max.dev_attr.attr,
> -	&sensor_dev_attr_temp2_crit.dev_attr.attr,
> -	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
> -	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
> -	&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
> -	&sensor_dev_attr_temp2_fault.dev_attr.attr,
> -	&sensor_dev_attr_fan1_input.dev_attr.attr,
> -	&sensor_dev_attr_fan1_min.dev_attr.attr,
> -	&sensor_dev_attr_fan1_max.dev_attr.attr,
> -	&sensor_dev_attr_fan1_target.dev_attr.attr,
> -	&sensor_dev_attr_fan1_fault.dev_attr.attr,
> -	&sensor_dev_attr_fan1_pulses.dev_attr.attr,
> -	&sensor_dev_attr_pwm1.dev_attr.attr,
> -	&sensor_dev_attr_pwm1_enable.dev_attr.attr,
> -	&sensor_dev_attr_pwm1_auto_channels_temp.dev_attr.attr,
>   	&sensor_dev_attr_pwm1_auto_point1_pwm.dev_attr.attr,
>   	&sensor_dev_attr_pwm1_auto_point2_pwm.dev_attr.attr,
>   	&sensor_dev_attr_pwm1_auto_point3_pwm.dev_attr.attr,
> @@ -753,13 +679,117 @@ static struct attribute *amc6821_attrs[] = {
>   	&sensor_dev_attr_temp2_auto_point3_temp.dev_attr.attr,
>   	NULL
>   };
> -
>   ATTRIBUTE_GROUPS(amc6821);
>   
> +static int amc6821_read(struct device *dev, enum hwmon_sensor_types type,
> +			u32 attr, int channel, long *val)
> +{
> +	switch (type) {
> +	case hwmon_temp:
> +		return amc6821_temp_read(dev, attr, channel, val);
> +	case hwmon_fan:
> +		return amc6821_fan_read(dev, attr, val);
> +	case hwmon_pwm:
> +		return amc6821_pwm_read(dev, attr, val);
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +}
> +
> +static int amc6821_write(struct device *dev, enum hwmon_sensor_types type,
> +			 u32 attr, int channel, long val)
> +{
> +	switch (type) {
> +	case hwmon_temp:
> +		return amc6821_temp_write(dev, attr, channel, val);
> +	case hwmon_fan:
> +		return amc6821_fan_write(dev, attr, val);
> +	case hwmon_pwm:
> +		return amc6821_pwm_write(dev, attr, val);
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +}
> +
> +static umode_t amc6821_is_visible(const void *data,
> +				  enum hwmon_sensor_types type,
> +				  u32 attr, int channel)
> +{
> +	switch (type) {
> +	case hwmon_temp:
> +		switch (attr) {
> +		case hwmon_temp_input:
> +		case hwmon_temp_min_alarm:
> +		case hwmon_temp_max_alarm:
> +		case hwmon_temp_crit_alarm:
> +		case hwmon_temp_fault:
> +			return 0444;
> +		case hwmon_temp_min:
> +		case hwmon_temp_max:
> +		case hwmon_temp_crit:
> +			return 0644;
> +		default:
> +			return 0;
> +		}
> +	case hwmon_fan:
> +		switch (attr) {
> +		case hwmon_fan_input:
> +		case hwmon_fan_fault:
> +			return 0444;
> +		case hwmon_fan_pulses:
> +		case hwmon_fan_min:
> +		case hwmon_fan_max:
> +		case hwmon_fan_target:
> +			return 0644;
> +		default:
> +			return 0;
> +		}
> +	case hwmon_pwm:
> +		switch (attr) {
> +		case hwmon_pwm_enable:
> +		case hwmon_pwm_input:
> +			return 0644;
> +		case hwmon_pwm_auto_channels_temp:
> +			return 0444;
> +		default:
> +			return 0;
> +		}
> +	default:
> +		return 0;
> +	}
> +}
> +
> +static const struct hwmon_channel_info * const amc6821_info[] = {
> +	HWMON_CHANNEL_INFO(temp,
> +			   HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
> +			   HWMON_T_CRIT | HWMON_T_MIN_ALARM |
> +			   HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM,
> +			   HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
> +			   HWMON_T_CRIT | HWMON_T_MIN_ALARM |
> +			   HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM |
> +			   HWMON_T_FAULT),
> +	HWMON_CHANNEL_INFO(fan,
> +			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_MAX |
> +			   HWMON_F_TARGET | HWMON_F_PULSES | HWMON_F_FAULT),
> +	HWMON_CHANNEL_INFO(pwm,
> +			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE |
> +			   HWMON_PWM_AUTO_CHANNELS_TEMP),
> +	NULL
> +};
> +
> +static const struct hwmon_ops amc6821_hwmon_ops = {
> +	.is_visible = amc6821_is_visible,
> +	.read = amc6821_read,
> +	.write = amc6821_write,
> +};
> +
> +static const struct hwmon_chip_info amc6821_chip_info = {
> +	.ops = &amc6821_hwmon_ops,
> +	.info = amc6821_info,
> +};
> +
>   /* Return 0 if detection is successful, -ENODEV otherwise */
> -static int amc6821_detect(
> -		struct i2c_client *client,
> -		struct i2c_board_info *info)
> +static int amc6821_detect(struct i2c_client *client, struct i2c_board_info *info)
>   {
>   	struct i2c_adapter *adapter = client->adapter;
>   	int address = client->addr;
> @@ -872,7 +902,6 @@ static int amc6821_probe(struct i2c_client *client)
>   	if (!data)
>   		return -ENOMEM;
>   
> -

Should be squashed with the previous commit.

Nice clean-up albeit very difficult to review in patch form, not sure 
there's anything we can do about it though. Maybe migrating one 
attribute at a time, but I would myself not be very happy if I was asked 
to do it :)

Cheers,
Quentin

Hi uentin,

On 7/1/24 10:46, Quentin Schulz wrote:

>>           return err;
>> -    return sysfs_emit(buf, "%d\n", !!(regval & mask));
>> +    *val = (int8_t)regval * 1000;
> 
> The discussed signed_extended32() in another patch would need to make it here too.
> 
Yes. Thanks for the reminder, I had missed that one.

>> -    return sprintf(buf, "%d\n", val);
>> +    err = regmap_bulk_read(regmap, reg, regs, 2);
>> +    if (err)
>> +        return err;
>> +
>> +    regval = (regs[1] << 8) | regs[0];
>> +    *val = 6000000 / (regval ? : 1);
>> +
> 
> Just putting a "bookmark" here since we're having a discussion about this logic in another thread for another patch.
> 
> Also... missing 0 here between the question mark and the colon?
> 
It translates to
	 *val = 6000000 / (regval ? regval : 1);
which is what I had wanted (divide by regval if regval != 0,
otherwise divide by 1 [i.e., return 6000000]).

I have it now as
	*val = regval ? 6000000 / regval : 0;

>> +static int amc6821_fan_write(struct device *dev, u32 attr, long val)
>> +{
>> +    struct amc6821_data *data = dev_get_drvdata(dev);
>> +    struct regmap *regmap = data->regmap;
>> +    u8 regs[2];
>> +    int reg;
>> +
>> +    if (attr == hwmon_fan_pulses) {
>> +        if (val != 2 && val != 4)
>> +            return -EINVAL;
>> +        return regmap_update_bits(regmap, AMC6821_REG_CONF4,
>> +                     AMC6821_CONF4_PSPR,
>> +                     val == 4 ? AMC6821_CONF4_PSPR : 0);
>> +    }
>> +
>> +    if (val < 0)
>> +        return -EINVAL;
>> +
>> +    val = clamp_val(6000000 / (val ? : 1), 0, 0xffff);
>> +
> 
> And another "bookmark" here.
> 

That is now
	val = val ? 6000000 / clamp_val(val, 1, 6000000) : 0;
         val = clamp_val(val, 0, 0xffff);

'val' is checked earlier and must be > 0 for the minimum
and target fan speed.
	
>> +    switch (attr) {
>> +    case hwmon_fan_min:
>> +        reg = AMC6821_REG_TACH_LLIMITL;
>> +        break;
>> +    case hwmon_fan_max:
>> +        reg = AMC6821_REG_TACH_HLIMITL;
>> +        break;
>> +    case hwmon_fan_target:
>> +        reg = AMC6821_REG_TACH_SETTINGL;
>> +        break;
>> +    default:
>> +        return -EOPNOTSUPP;
>> +    }
>> +
>> +    regs[0] = val & 0xff;
>> +    regs[1] = val >> 8;
>> +
>> +    return regmap_bulk_write(data->regmap, reg, regs, 2);
>>   }
>>   static ssize_t temp_auto_point_temp_show(struct device *dev,
>>                        struct device_attribute *devattr,
>>                        char *buf)
>>   {
>> +    struct amc6821_data *data = dev_get_drvdata(dev);
>>       int ix = to_sensor_dev_attr_2(devattr)->index;
>>       int nr = to_sensor_dev_attr_2(devattr)->nr;
>> -    struct amc6821_data *data = dev_get_drvdata(dev);
> 
> Should be squashed with the appropriate commit?
> 

Yes, the previous one.

>>       switch (nr) {
>>       case 1:
>> @@ -423,7 +495,6 @@ static ssize_t temp_auto_point_temp_show(struct device *dev,
>>           return sprintf(buf, "%d\n",
>>               data->temp2_auto_point_temp[ix] * 1000);
>>       default:
>> -        dev_dbg(dev, "Unknown attr->nr (%d).\n", nr);
> 
> Not sure this is related? Maybe a separate commit?
> 

It should have been part of the previous commit, where it is explained ("remove
spurious debug messages which would only be seen as result of a bug in the code")

>> @@ -872,7 +902,6 @@ static int amc6821_probe(struct i2c_client *client)
>>       if (!data)
>>           return -ENOMEM;
>> -
> 
> Should be squashed with the previous commit.
> 
Ok.

> Nice clean-up albeit very difficult to review in patch form, not sure there's anything we can do about it though. Maybe migrating one attribute at a time, but I would myself not be very happy if I was asked to do it :)
> 

Yes, that is always the problem with the conversion to the with_info API.
I don't think it would make much sense to try to split it further.

Thanks a lot for the detailed review!

Guenter