1 files changed, 86 insertions, 128 deletions

diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c
index 4d28150..96862c6 100644
--- a/drivers/hwmon/ina2xx.c
+++ b/drivers/hwmon/ina2xx.c
@@ -37,6 +37,7 @@
 #include <linux/of.h>
 #include <linux/delay.h>
 #include <linux/util_macros.h>
+#include <linux/regmap.h>
 
 #include <linux/platform_data/ina2xx.h>
 
@@ -84,6 +85,11 @@
  */
 #define INA226_TOTAL_CONV_TIME_DEFAULT	2200
 
+static struct regmap_config ina2xx_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 16,
+};
+
 enum ina2xx_ids { ina219, ina226 };
 
 struct ina2xx_config {
@@ -97,20 +103,14 @@ struct ina2xx_config {
 };
 
 struct ina2xx_data {
-	struct i2c_client *client;
 	const struct ina2xx_config *config;
 
 	long rshunt;
-	u16 curr_config;
-
-	struct mutex update_lock;
-	bool valid;
-	unsigned long last_updated;
-	int update_interval; /* in jiffies */
+	struct mutex config_lock;
+	struct regmap *regmap;
 
 	int kind;
 	const struct attribute_group *groups[INA2XX_MAX_ATTRIBUTE_GROUPS];
-	u16 regs[INA2XX_MAX_REGISTERS];
 };
 
 static const struct ina2xx_config ina2xx_config[] = {
@@ -153,7 +153,11 @@ static int ina226_reg_to_interval(u16 config)
 	return DIV_ROUND_CLOSEST(avg * INA226_TOTAL_CONV_TIME_DEFAULT, 1000);
 }
 
-static u16 ina226_interval_to_reg(int interval, u16 config)
+/*
+ * Return the new, shifted AVG field value of CONFIG register,
+ * to use with regmap_update_bits
+ */
+static u16 ina226_interval_to_reg(int interval)
 {
 	int avg, avg_bits;
 
@@ -162,15 +166,7 @@ static u16 ina226_interval_to_reg(int interval, u16 config)
 	avg_bits = find_closest(avg, ina226_avg_tab,
 				ARRAY_SIZE(ina226_avg_tab));
 
-	return (config & ~INA226_AVG_RD_MASK) | INA226_SHIFT_AVG(avg_bits);
-}
-
-static void ina226_set_update_interval(struct ina2xx_data *data)
-{
-	int ms;
-
-	ms = ina226_reg_to_interval(data->curr_config);
-	data->update_interval = msecs_to_jiffies(ms);
+	return INA226_SHIFT_AVG(avg_bits);
 }
 
 static int ina2xx_calibrate(struct ina2xx_data *data)
@@ -178,8 +174,7 @@ static int ina2xx_calibrate(struct ina2xx_data *data)
 	u16 val = DIV_ROUND_CLOSEST(data->config->calibration_factor,
 				    data->rshunt);
 
-	return i2c_smbus_write_word_swapped(data->client,
-					    INA2XX_CALIBRATION, val);
+	return regmap_write(data->regmap, INA2XX_CALIBRATION, val);
 }
 
 /*
@@ -187,12 +182,8 @@ static int ina2xx_calibrate(struct ina2xx_data *data)
  */
 static int ina2xx_init(struct ina2xx_data *data)
 {
-	struct i2c_client *client = data->client;
-	int ret;
-
-	/* device configuration */
-	ret = i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
-					   data->curr_config);
+	int ret = regmap_write(data->regmap, INA2XX_CONFIG,
+			       data->config->config_default);
 	if (ret < 0)
 		return ret;
 
@@ -203,47 +194,52 @@ static int ina2xx_init(struct ina2xx_data *data)
 	return ina2xx_calibrate(data);
 }
 
-static int ina2xx_do_update(struct device *dev)
+static int ina2xx_read_reg(struct device *dev, int reg, unsigned int *regval)
 {
 	struct ina2xx_data *data = dev_get_drvdata(dev);
-	struct i2c_client *client = data->client;
-	int i, rv, retry;
+	int ret, retry;
 
-	dev_dbg(&client->dev, "Starting ina2xx update\n");
+	dev_dbg(dev, "Starting register %d read\n", reg);
 
 	for (retry = 5; retry; retry--) {
-		/* Read all registers */
-		for (i = 0; i < data->config->registers; i++) {
-			rv = i2c_smbus_read_word_swapped(client, i);
-			if (rv < 0)
-				return rv;
-			data->regs[i] = rv;
-		}
+
+		ret = regmap_read(data->regmap, reg, regval);
+		if (ret < 0)
+			return ret;
+
+		dev_dbg(dev, "read %d, val = 0x%04x\n", reg, *regval);
 
 		/*
 		 * If the current value in the calibration register is 0, the
 		 * power and current registers will also remain at 0. In case
 		 * the chip has been reset let's check the calibration
 		 * register and reinitialize if needed.
+		 * We do that extra read of the calibration register if there
+		 * is some hint of a chip reset.
 		 */
-		if (data->regs[INA2XX_CALIBRATION] == 0) {
-			dev_warn(dev, "chip not calibrated, reinitializing\n");
-
-			rv = ina2xx_init(data);
-			if (rv < 0)
-				return rv;
-
-			/*
-			 * Let's make sure the power and current registers
-			 * have been updated before trying again.
-			 */
-			msleep(INA2XX_MAX_DELAY);
-			continue;
+		if (*regval == 0) {
+			unsigned int cal;
+
+			ret = regmap_read(data->regmap, INA2XX_CALIBRATION,
+					  &cal);
+			if (ret < 0)
+				return ret;
+
+			if (cal == 0) {
+				dev_warn(dev, "chip not calibrated, reinitializing\n");
+
+				ret = ina2xx_init(data);
+				if (ret < 0)
+					return ret;
+				/*
+				 * Let's make sure the power and current
+				 * registers have been updated before trying
+				 * again.
+				 */
+				msleep(INA2XX_MAX_DELAY);
+				continue;
+			}
 		}
-
-		data->last_updated = jiffies;
-		data->valid = 1;
-
 		return 0;
 	}
 
@@ -256,51 +252,31 @@ static int ina2xx_do_update(struct device *dev)
 	return -ENODEV;
 }
 
-static struct ina2xx_data *ina2xx_update_device(struct device *dev)
-{
-	struct ina2xx_data *data = dev_get_drvdata(dev);
-	struct ina2xx_data *ret = data;
-	unsigned long after;
-	int rv;
-
-	mutex_lock(&data->update_lock);
-
-	after = data->last_updated + data->update_interval;
-	if (time_after(jiffies, after) || !data->valid) {
-		rv = ina2xx_do_update(dev);
-		if (rv < 0)
-			ret = ERR_PTR(rv);
-	}
-
-	mutex_unlock(&data->update_lock);
-	return ret;
-}
-
-static int ina2xx_get_value(struct ina2xx_data *data, u8 reg)
+static int ina2xx_get_value(struct ina2xx_data *data, u8 reg,
+			    unsigned int regval)
 {
 	int val;
 
 	switch (reg) {
 	case INA2XX_SHUNT_VOLTAGE:
 		/* signed register */
-		val = DIV_ROUND_CLOSEST((s16)data->regs[reg],
-					data->config->shunt_div);
+		val = DIV_ROUND_CLOSEST((s16)regval, data->config->shunt_div);
 		break;
 	case INA2XX_BUS_VOLTAGE:
-		val = (data->regs[reg] >> data->config->bus_voltage_shift)
+		val = (regval >> data->config->bus_voltage_shift)
 		  * data->config->bus_voltage_lsb;
 		val = DIV_ROUND_CLOSEST(val, 1000);
 		break;
 	case INA2XX_POWER:
-		val = data->regs[reg] * data->config->power_lsb;
+		val = regval * data->config->power_lsb;
 		break;
 	case INA2XX_CURRENT:
 		/* signed register, LSB=1mA (selected), in mA */
-		val = (s16)data->regs[reg];
+		val = (s16)regval;
 		break;
 	case INA2XX_CALIBRATION:
 		val = DIV_ROUND_CLOSEST(data->config->calibration_factor,
-					data->regs[reg]);
+					regval);
 		break;
 	default:
 		/* programmer goofed */
@@ -316,25 +292,25 @@ static ssize_t ina2xx_show_value(struct device *dev,
 				 struct device_attribute *da, char *buf)
 {
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
-	struct ina2xx_data *data = ina2xx_update_device(dev);
+	struct ina2xx_data *data = dev_get_drvdata(dev);
+	unsigned int regval;
 
-	if (IS_ERR(data))
-		return PTR_ERR(data);
+	int err = ina2xx_read_reg(dev, attr->index, &regval);
+
+	if (err < 0)
+		return err;
 
 	return snprintf(buf, PAGE_SIZE, "%d\n",
-			ina2xx_get_value(data, attr->index));
+			ina2xx_get_value(data, attr->index, regval));
 }
 
 static ssize_t ina2xx_set_shunt(struct device *dev,
 				struct device_attribute *da,
 				const char *buf, size_t count)
 {
-	struct ina2xx_data *data = ina2xx_update_device(dev);
 	unsigned long val;
 	int status;
-
-	if (IS_ERR(data))
-		return PTR_ERR(data);
+	struct ina2xx_data *data = dev_get_drvdata(dev);
 
 	status = kstrtoul(buf, 10, &val);
 	if (status < 0)
@@ -345,10 +321,10 @@ static ssize_t ina2xx_set_shunt(struct device *dev,
 	    val > data->config->calibration_factor)
 		return -EINVAL;
 
-	mutex_lock(&data->update_lock);
+	mutex_lock(&data->config_lock);
 	data->rshunt = val;
 	status = ina2xx_calibrate(data);
-	mutex_unlock(&data->update_lock);
+	mutex_unlock(&data->config_lock);
 	if (status < 0)
 		return status;
 
@@ -370,17 +346,9 @@ static ssize_t ina226_set_interval(struct device *dev,
 	if (val > INT_MAX || val == 0)
 		return -EINVAL;
 
-	mutex_lock(&data->update_lock);
-	data->curr_config = ina226_interval_to_reg(val,
-						   data->regs[INA2XX_CONFIG]);
-	status = i2c_smbus_write_word_swapped(data->client,
-					      INA2XX_CONFIG,
-					      data->curr_config);
-
-	ina226_set_update_interval(data);
-	/* Make sure the next access re-reads all registers. */
-	data->valid = 0;
-	mutex_unlock(&data->update_lock);
+	status = regmap_update_bits(data->regmap, INA2XX_CONFIG,
+				    INA226_AVG_RD_MASK,
+				    ina226_interval_to_reg(val));
 	if (status < 0)
 		return status;
 
@@ -390,18 +358,15 @@ static ssize_t ina226_set_interval(struct device *dev,
 static ssize_t ina226_show_interval(struct device *dev,
 				    struct device_attribute *da, char *buf)
 {
-	struct ina2xx_data *data = ina2xx_update_device(dev);
+	struct ina2xx_data *data = dev_get_drvdata(dev);
+	int status;
+	unsigned int regval;
 
-	if (IS_ERR(data))
-		return PTR_ERR(data);
+	status = regmap_read(data->regmap, INA2XX_CONFIG, &regval);
+	if (status)
+		return status;
 
-	/*
-	 * We don't use data->update_interval here as we want to display
-	 * the actual interval used by the chip and jiffies_to_msecs()
-	 * doesn't seem to be accurate enough.
-	 */
-	return snprintf(buf, PAGE_SIZE, "%d\n",
-			ina226_reg_to_interval(data->regs[INA2XX_CONFIG]));
+	return snprintf(buf, PAGE_SIZE, "%d\n", ina226_reg_to_interval(regval));
 }
 
 /* shunt voltage */
@@ -455,7 +420,6 @@ static const struct attribute_group ina226_group = {
 static int ina2xx_probe(struct i2c_client *client,
 			const struct i2c_device_id *id)
 {
-	struct i2c_adapter *adapter = client->adapter;
 	struct ina2xx_platform_data *pdata;
 	struct device *dev = &client->dev;
 	struct ina2xx_data *data;
@@ -463,9 +427,6 @@ static int ina2xx_probe(struct i2c_client *client,
 	u32 val;
 	int ret, group = 0;
 
-	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
-		return -ENODEV;
-
 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;
@@ -483,29 +444,26 @@ static int ina2xx_probe(struct i2c_client *client,
 	/* set the device type */
 	data->kind = id->driver_data;
 	data->config = &ina2xx_config[data->kind];
-	data->curr_config = data->config->config_default;
-	data->client = client;
-
-	/*
-	 * Ina226 has a variable update_interval. For ina219 we
-	 * use a constant value.
-	 */
-	if (data->kind == ina226)
-		ina226_set_update_interval(data);
-	else
-		data->update_interval = HZ / INA2XX_CONVERSION_RATE;
 
 	if (data->rshunt <= 0 ||
 	    data->rshunt > data->config->calibration_factor)
 		return -ENODEV;
 
+	ina2xx_regmap_config.max_register = data->config->registers;
+
+	data->regmap = devm_regmap_init_i2c(client, &ina2xx_regmap_config);
+	if (IS_ERR(data->regmap)) {
+		dev_err(dev, "failed to allocate register map\n");
+		return PTR_ERR(data->regmap);
+	}
+
 	ret = ina2xx_init(data);
 	if (ret < 0) {
 		dev_err(dev, "error configuring the device: %d\n", ret);
 		return -ENODEV;
 	}
 
-	mutex_init(&data->update_lock);
+	mutex_init(&data->config_lock);
 
 	data->groups[group++] = &ina2xx_group;
 	if (data->kind == ina226)