hwmon: (adt7x10) Convert to use regmap

Using regmap lets us use the regmap subsystem for SPI vs. I2C register
accesses. It lets us hide access differences in backend code and lets
the common code just access registers without knowing their size.
We can also use regmap for register caching.

Tested-by: Cosmin Tanislav <cosmin.tanislav@analog.com>
Reviewed-by: Cosmin Tanislav <cosmin.tanislav@analog.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

1 files changed, 81 insertions, 144 deletions

diff --git a/drivers/hwmon/adt7x10.c b/drivers/hwmon/adt7x10.c
index e9d33aa78a19..05dd48b707b4 100644
--- a/drivers/hwmon/adt7x10.c
+++ b/drivers/hwmon/adt7x10.c
@@ -18,6 +18,7 @@
 #include <linux/mutex.h>
 #include <linux/delay.h>
 #include <linux/interrupt.h>
+#include <linux/regmap.h>
 
 #include "adt7x10.h"
 
@@ -53,46 +54,15 @@
 
 /* Each client has this additional data */
 struct adt7x10_data {
-	const struct adt7x10_ops *ops;
+	struct regmap		*regmap;
 	const char		*name;
 	struct device		*hwmon_dev;
 	struct mutex		update_lock;
 	u8			config;
 	u8			oldconfig;
-	bool			valid;		/* true if registers valid */
-	unsigned long		last_updated;	/* In jiffies */
-	s16			temp[4];	/* Register values,
-						   0 = input
-						   1 = high
-						   2 = low
-						   3 = critical */
-	u8			hyst;		/* hysteresis offset */
+	bool			valid;		/* true if temperature valid */
 };
 
-static int adt7x10_read_byte(struct device *dev, u8 reg)
-{
-	struct adt7x10_data *d = dev_get_drvdata(dev);
-	return d->ops->read_byte(dev, reg);
-}
-
-static int adt7x10_write_byte(struct device *dev, u8 reg, u8 data)
-{
-	struct adt7x10_data *d = dev_get_drvdata(dev);
-	return d->ops->write_byte(dev, reg, data);
-}
-
-static int adt7x10_read_word(struct device *dev, u8 reg)
-{
-	struct adt7x10_data *d = dev_get_drvdata(dev);
-	return d->ops->read_word(dev, reg);
-}
-
-static int adt7x10_write_word(struct device *dev, u8 reg, u16 data)
-{
-	struct adt7x10_data *d = dev_get_drvdata(dev);
-	return d->ops->write_word(dev, reg, data);
-}
-
 static const u8 ADT7X10_REG_TEMP[4] = {
 	ADT7X10_TEMPERATURE,		/* input */
 	ADT7X10_T_ALARM_HIGH,		/* high */
@@ -103,10 +73,12 @@ static const u8 ADT7X10_REG_TEMP[4] = {
 static irqreturn_t adt7x10_irq_handler(int irq, void *private)
 {
 	struct device *dev = private;
-	int status;
+	struct adt7x10_data *d = dev_get_drvdata(dev);
+	unsigned int status;
+	int ret;
 
-	status = adt7x10_read_byte(dev, ADT7X10_STATUS);
-	if (status < 0)
+	ret = regmap_read(d->regmap, ADT7X10_STATUS, &status);
+	if (ret < 0)
 		return IRQ_HANDLED;
 
 	if (status & ADT7X10_STAT_T_HIGH)
@@ -119,14 +91,15 @@ static irqreturn_t adt7x10_irq_handler(int irq, void *private)
 	return IRQ_HANDLED;
 }
 
-static int adt7x10_temp_ready(struct device *dev)
+static int adt7x10_temp_ready(struct regmap *regmap)
 {
-	int i, status;
+	unsigned int status;
+	int i, ret;
 
 	for (i = 0; i < 6; i++) {
-		status = adt7x10_read_byte(dev, ADT7X10_STATUS);
-		if (status < 0)
-			return status;
+		ret = regmap_read(regmap, ADT7X10_STATUS, &status);
+		if (ret < 0)
+			return ret;
 		if (!(status & ADT7X10_STAT_NOT_RDY))
 			return 0;
 		msleep(60);
@@ -134,71 +107,10 @@ static int adt7x10_temp_ready(struct device *dev)
 	return -ETIMEDOUT;
 }
 
-static int adt7x10_update_temp(struct device *dev)
-{
-	struct adt7x10_data *data = dev_get_drvdata(dev);
-	int ret = 0;
-
-	mutex_lock(&data->update_lock);
-
-	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
-	    || !data->valid) {
-		int temp;
-
-		dev_dbg(dev, "Starting update\n");
-
-		ret = adt7x10_temp_ready(dev); /* check for new value */
-		if (ret)
-			goto abort;
-
-		temp = adt7x10_read_word(dev, ADT7X10_REG_TEMP[0]);
-		if (temp < 0) {
-			ret = temp;
-			dev_dbg(dev, "Failed to read value: reg %d, error %d\n",
-				ADT7X10_REG_TEMP[0], ret);
-			goto abort;
-		}
-		data->temp[0] = temp;
-		data->last_updated = jiffies;
-		data->valid = true;
-	}
-
-abort:
-	mutex_unlock(&data->update_lock);
-	return ret;
-}
-
-static int adt7x10_fill_cache(struct device *dev)
-{
-	struct adt7x10_data *data = dev_get_drvdata(dev);
-	int ret;
-	int i;
-
-	for (i = 1; i < ARRAY_SIZE(data->temp); i++) {
-		ret = adt7x10_read_word(dev, ADT7X10_REG_TEMP[i]);
-		if (ret < 0) {
-			dev_dbg(dev, "Failed to read value: reg %d, error %d\n",
-				ADT7X10_REG_TEMP[i], ret);
-			return ret;
-		}
-		data->temp[i] = ret;
-	}
-
-	ret = adt7x10_read_byte(dev, ADT7X10_T_HYST);
-	if (ret < 0) {
-		dev_dbg(dev, "Failed to read value: reg %d, error %d\n",
-				ADT7X10_T_HYST, ret);
-		return ret;
-	}
-	data->hyst = ret;
-
-	return 0;
-}
-
 static s16 ADT7X10_TEMP_TO_REG(long temp)
 {
 	return DIV_ROUND_CLOSEST(clamp_val(temp, ADT7X10_TEMP_MIN,
-					       ADT7X10_TEMP_MAX) * 128, 1000);
+					   ADT7X10_TEMP_MAX) * 128, 1000);
 }
 
 static int ADT7X10_REG_TO_TEMP(struct adt7x10_data *data, s16 reg)
@@ -222,18 +134,26 @@ static ssize_t adt7x10_temp_show(struct device *dev,
 {
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
 	struct adt7x10_data *data = dev_get_drvdata(dev);
+	unsigned int val;
+	int ret;
 
-
-	if (attr->index == 0) {
-		int ret;
-
-		ret = adt7x10_update_temp(dev);
-		if (ret)
+	mutex_lock(&data->update_lock);
+	if (attr->index == 0 && !data->valid) {
+		/* wait for valid temperature */
+		ret = adt7x10_temp_ready(data->regmap);
+		if (ret) {
+			mutex_unlock(&data->update_lock);
 			return ret;
+		}
+		data->valid = true;
 	}
+	mutex_unlock(&data->update_lock);
 
-	return sprintf(buf, "%d\n", ADT7X10_REG_TO_TEMP(data,
-		       data->temp[attr->index]));
+	ret = regmap_read(data->regmap, ADT7X10_REG_TEMP[attr->index], &val);
+	if (ret)
+		return ret;
+
+	return sprintf(buf, "%d\n", ADT7X10_REG_TO_TEMP(data, val));
 }
 
 static ssize_t adt7x10_temp_store(struct device *dev,
@@ -251,12 +171,10 @@ static ssize_t adt7x10_temp_store(struct device *dev,
 		return ret;
 
 	mutex_lock(&data->update_lock);
-	data->temp[nr] = ADT7X10_TEMP_TO_REG(temp);
-	ret = adt7x10_write_word(dev, ADT7X10_REG_TEMP[nr], data->temp[nr]);
-	if (ret)
-		count = ret;
+	ret = regmap_write(data->regmap, ADT7X10_REG_TEMP[nr],
+			   ADT7X10_TEMP_TO_REG(temp));
 	mutex_unlock(&data->update_lock);
-	return count;
+	return ret ? : count;
 }
 
 static ssize_t adt7x10_t_hyst_show(struct device *dev,
@@ -265,9 +183,21 @@ static ssize_t adt7x10_t_hyst_show(struct device *dev,
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
 	struct adt7x10_data *data = dev_get_drvdata(dev);
 	int nr = attr->index;
-	int hyst;
+	int hyst, temp, ret;
+
+	mutex_lock(&data->update_lock);
+	ret = regmap_read(data->regmap, ADT7X10_T_HYST, &hyst);
+	if (ret) {
+		mutex_unlock(&data->update_lock);
+		return ret;
+	}
+
+	ret = regmap_read(data->regmap, ADT7X10_REG_TEMP[nr], &temp);
+	mutex_unlock(&data->update_lock);
+	if (ret)
+		return ret;
 
-	hyst = (data->hyst & ADT7X10_T_HYST_MASK) * 1000;
+	hyst = (hyst & ADT7X10_T_HYST_MASK) * 1000;
 
 	/*
 	 * hysteresis is stored as a 4 bit offset in the device, convert it
@@ -275,8 +205,8 @@ static ssize_t adt7x10_t_hyst_show(struct device *dev,
 	 */
 	if (nr == 2)	/* min has positive offset, others have negative */
 		hyst = -hyst;
-	return sprintf(buf, "%d\n",
-		       ADT7X10_REG_TO_TEMP(data, data->temp[nr]) - hyst);
+
+	return sprintf(buf, "%d\n", ADT7X10_REG_TO_TEMP(data, temp) - hyst);
 }
 
 static ssize_t adt7x10_t_hyst_store(struct device *dev,
@@ -284,35 +214,45 @@ static ssize_t adt7x10_t_hyst_store(struct device *dev,
 				    const char *buf, size_t count)
 {
 	struct adt7x10_data *data = dev_get_drvdata(dev);
+	unsigned int regval;
 	int limit, ret;
 	long hyst;
 
 	ret = kstrtol(buf, 10, &hyst);
 	if (ret)
 		return ret;
+
+	mutex_lock(&data->update_lock);
+
 	/* convert absolute hysteresis value to a 4 bit delta value */
-	limit = ADT7X10_REG_TO_TEMP(data, data->temp[1]);
-	hyst = clamp_val(hyst, ADT7X10_TEMP_MIN, ADT7X10_TEMP_MAX);
-	data->hyst = clamp_val(DIV_ROUND_CLOSEST(limit - hyst, 1000),
-				   0, ADT7X10_T_HYST_MASK);
-	ret = adt7x10_write_byte(dev, ADT7X10_T_HYST, data->hyst);
-	if (ret)
-		return ret;
+	ret = regmap_read(data->regmap, ADT7X10_T_ALARM_HIGH, &regval);
+	if (ret < 0)
+		goto abort;
 
-	return count;
+	limit = ADT7X10_REG_TO_TEMP(data, regval);
+
+	hyst = clamp_val(hyst, ADT7X10_TEMP_MIN, ADT7X10_TEMP_MAX);
+	regval = clamp_val(DIV_ROUND_CLOSEST(limit - hyst, 1000), 0,
+			   ADT7X10_T_HYST_MASK);
+	ret = regmap_write(data->regmap, ADT7X10_T_HYST, regval);
+abort:
+	mutex_unlock(&data->update_lock);
+	return ret ? : count;
 }
 
 static ssize_t adt7x10_alarm_show(struct device *dev,
 				  struct device_attribute *da, char *buf)
 {
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	struct adt7x10_data *data = dev_get_drvdata(dev);
+	unsigned int status;
 	int ret;
 
-	ret = adt7x10_read_byte(dev, ADT7X10_STATUS);
+	ret = regmap_read(data->regmap, ADT7X10_STATUS, &status);
 	if (ret < 0)
 		return ret;
 
-	return sprintf(buf, "%d\n", !!(ret & attr->index));
+	return sprintf(buf, "%d\n", !!(status & attr->index));
 }
 
 static ssize_t name_show(struct device *dev, struct device_attribute *da,
@@ -357,28 +297,29 @@ static const struct attribute_group adt7x10_group = {
 };
 
 int adt7x10_probe(struct device *dev, const char *name, int irq,
-		  const struct adt7x10_ops *ops)
+		  struct regmap *regmap)
 {
 	struct adt7x10_data *data;
+	unsigned int config;
 	int ret;
 
 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;
 
-	data->ops = ops;
+	data->regmap = regmap;
 	data->name = name;
 
 	dev_set_drvdata(dev, data);
 	mutex_init(&data->update_lock);
 
 	/* configure as specified */
-	ret = adt7x10_read_byte(dev, ADT7X10_CONFIG);
+	ret = regmap_read(regmap, ADT7X10_CONFIG, &config);
 	if (ret < 0) {
 		dev_dbg(dev, "Can't read config? %d\n", ret);
 		return ret;
 	}
-	data->oldconfig = ret;
+	data->oldconfig = config;
 
 	/*
 	 * Set to 16 bit resolution, continous conversion and comparator mode.
@@ -389,16 +330,12 @@ int adt7x10_probe(struct device *dev, const char *name, int irq,
 	data->config |= ADT7X10_FULL | ADT7X10_RESOLUTION | ADT7X10_EVENT_MODE;
 
 	if (data->config != data->oldconfig) {
-		ret = adt7x10_write_byte(dev, ADT7X10_CONFIG, data->config);
+		ret = regmap_write(regmap, ADT7X10_CONFIG, data->config);
 		if (ret)
 			return ret;
 	}
 	dev_dbg(dev, "Config %02x\n", data->config);
 
-	ret = adt7x10_fill_cache(dev);
-	if (ret)
-		goto exit_restore;
-
 	/* Register sysfs hooks */
 	ret = sysfs_create_group(&dev->kobj, &adt7x10_group);
 	if (ret)
@@ -439,7 +376,7 @@ exit_remove_name:
 exit_remove:
 	sysfs_remove_group(&dev->kobj, &adt7x10_group);
 exit_restore:
-	adt7x10_write_byte(dev, ADT7X10_CONFIG, data->oldconfig);
+	regmap_write(regmap, ADT7X10_CONFIG, data->oldconfig);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(adt7x10_probe);
@@ -456,7 +393,7 @@ void adt7x10_remove(struct device *dev, int irq)
 		device_remove_file(dev, &dev_attr_name);
 	sysfs_remove_group(&dev->kobj, &adt7x10_group);
 	if (data->oldconfig != data->config)
-		adt7x10_write_byte(dev, ADT7X10_CONFIG, data->oldconfig);
+		regmap_write(data->regmap, ADT7X10_CONFIG, data->oldconfig);
 }
 EXPORT_SYMBOL_GPL(adt7x10_remove);
 
@@ -466,15 +403,15 @@ static int adt7x10_suspend(struct device *dev)
 {
 	struct adt7x10_data *data = dev_get_drvdata(dev);
 
-	return adt7x10_write_byte(dev, ADT7X10_CONFIG,
-		data->config | ADT7X10_PD);
+	return regmap_write(data->regmap, ADT7X10_CONFIG,
+			    data->config | ADT7X10_PD);
 }
 
 static int adt7x10_resume(struct device *dev)
 {
 	struct adt7x10_data *data = dev_get_drvdata(dev);
 
-	return adt7x10_write_byte(dev, ADT7X10_CONFIG, data->config);
+	return regmap_write(data->regmap, ADT7X10_CONFIG, data->config);
 }
 
 SIMPLE_DEV_PM_OPS(adt7x10_dev_pm_ops, adt7x10_suspend, adt7x10_resume);