Re: [PATCH v1] hwmon: (lm75) Add support for Nuvoton NCT7715

Signed-off-by: Sheng-Yuan Huang <redacted>
---
  .../devicetree/bindings/hwmon/lm75.yaml       |  1 +
  Documentation/hwmon/lm75.rst                  |  6 ++
  drivers/hwmon/lm75.c                          | 57 ++++++++++++++++++-
  3 files changed, 62 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/hwmon/lm75.yaml b/Documentation/devicetree/bindings/hwmon/lm75.yaml
index b48bf3fd721f..832a8c5d83e9 100644
--- a/Documentation/devicetree/bindings/hwmon/lm75.yaml
+++ b/Documentation/devicetree/bindings/hwmon/lm75.yaml

@@ -31,6 +31,7 @@ properties:
        - nxp,p3t1750
        - nxp,p3t1755
        - nxp,pct2075
+      - nuvoton,nct7715
        - st,stds75
        - st,stlm75
        - microchip,tcn75

diff --git a/Documentation/hwmon/lm75.rst b/Documentation/hwmon/lm75.rst
index ca46754e028b..fac0b8f29ddc 100644
--- a/Documentation/hwmon/lm75.rst
+++ b/Documentation/hwmon/lm75.rst

@@ -150,6 +150,12 @@ Supported chips:
  
                 https://ams.com/documents/20143/36005/AS6200_DS000449_4-00.pdf
  
+  * Nuvoton NCT7715
+
+    Prefix: 'nct7715'
+
+    Addresses scanned: none
+
  Author: Frodo Looijaard <frodol@dds.nl>
  
  Description

diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
index 2d2d752aeac9..0b55f6b7c68d 100644
--- a/drivers/hwmon/lm75.c
+++ b/drivers/hwmon/lm75.c

@@ -39,6 +39,7 @@ enum lm75_type {		/* keep sorted in alphabetical order */
  	max6626,
  	max31725,
  	mcp980x,
+	nct7715,
  	p3t1750,
  	p3t1755,
  	pct2075,

@@ -107,6 +108,15 @@ static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
  #define LM75_REG_MAX		0x03
  #define PCT2075_REG_IDLE	0x04
  
+#define NCT7715_CONFIG_RESOLUTION_12_BIT	GENMASK(14, 13)
+#define NCT7715_CONFIG_SHUTDOWN			BIT(8)
+#define NCT7715_CONFIG_CONVERSION_RATE_MASK	GENMASK(7, 6)
+#define NCT7715_CONFIG_EXTENDED_MODE		BIT(4)
+#define NCT7715_CONFIG_RATE_0_25HZ		0
+#define NCT7715_CONFIG_RATE_1HZ			BIT(6)
+#define NCT7715_CONFIG_RATE_4HZ			BIT(7)
+#define NCT7715_CONFIG_RATE_8HZ			GENMASK(7, 6)
+
  struct lm75_data {
  	const char *label;
  	struct regmap			*regmap;

@@ -122,6 +132,10 @@ struct lm75_data {
  /*-----------------------------------------------------------------------*/
  
  static const u8 lm75_sample_set_masks[] = { 0 << 5, 1 << 5, 2 << 5, 3 << 5 };
+static const u16 nct7715_sample_set_masks[] = {
+	NCT7715_CONFIG_RATE_8HZ, NCT7715_CONFIG_RATE_4HZ,
+	NCT7715_CONFIG_RATE_1HZ, NCT7715_CONFIG_RATE_0_25HZ
+};
  
  #define LM75_ALERT_POLARITY_HIGH_8_BIT	(BIT(2))
  #define LM75_ALERT_POLARITY_HIGH_16_BIT	(BIT(2) << 8)

@@ -259,6 +273,15 @@ static const struct lm75_params device_params[] = {
  		.sample_times = (unsigned int []){ 30, 60, 120, 240 },
  		.resolutions = (u8 []) {9, 10, 11, 12 },
  	},
+	[nct7715] = {
+		.config_reg_16bits = true,
+		.set_mask = NCT7715_CONFIG_RESOLUTION_12_BIT,
+		.clr_mask = NCT7715_CONFIG_EXTENDED_MODE,
+		.default_resolution = 12,
+		.default_sample_time = 250,
+		.num_sample_times = 4,
+		.sample_times = (unsigned int []){ 125, 250, 1000, 4000 },
+	},
  	[tmp100] = {
  		.set_mask = 3 << 5,	/* 12-bit mode */
  		.clr_mask = 1 << 7,	/* not one-shot mode */

@@ -354,6 +377,11 @@ static inline long lm75_reg_to_mc(s16 temp, u8 resolution)
  static inline int lm75_write_config(struct lm75_data *data, u16 set_mask,
  				    u16 clr_mask)
  {
+	if (data->kind == nct7715)
+		return regmap_update_bits(data->regmap, LM75_REG_CONF,
+					  clr_mask | set_mask | NCT7715_CONFIG_SHUTDOWN,
+					  set_mask);
+
  	return regmap_update_bits(data->regmap, LM75_REG_CONF,
  				  clr_mask | set_mask | LM75_SHUTDOWN, set_mask);
  }

@@ -486,6 +514,13 @@ static int lm75_update_interval(struct device *dev, long val)
  		if (data->params->resolutions)
  			data->resolution = data->params->resolutions[index];
  		break;
+	case nct7715:
+		err = lm75_write_config(data, nct7715_sample_set_masks[index],
+					NCT7715_CONFIG_CONVERSION_RATE_MASK);
+		if (err)
+			return err;
+		data->sample_time = data->params->sample_times[index];
+		break;
  	case tmp112:
  	case as6200:
  		err = regmap_update_bits(data->regmap, LM75_REG_CONF,

@@ -609,6 +644,8 @@ static int lm75_i2c_reg_read(void *context, unsigned int reg, unsigned int *val)
  	if (reg == LM75_REG_CONF) {
  		if (!data->params->config_reg_16bits)
  			ret = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
+		else if (data->kind == nct7715)
+			ret = i2c_smbus_read_word_swapped(client, LM75_REG_CONF);
  		else
  			ret = i2c_smbus_read_word_data(client, LM75_REG_CONF);
  	} else {

@@ -628,8 +665,11 @@ static int lm75_i2c_reg_write(void *context, unsigned int reg, unsigned int val)
  	if (reg == PCT2075_REG_IDLE ||
  	    (reg == LM75_REG_CONF && !data->params->config_reg_16bits))
  		return i2c_smbus_write_byte_data(client, reg, val);
-	else if (reg == LM75_REG_CONF)
+	else if (reg == LM75_REG_CONF) {
+		if (data->kind == nct7715)
+			return i2c_smbus_write_word_swapped(client, reg, val);