[RFC PATCH] hwmon: (max6650) Convert to be a platform driver

From: Laszlo Papp
Date: Thu Feb 13 2014 - 03:51:09 EST


The MFD driver has now been added, so this driver is now being adopted to be a
subdevice driver on top of it. This means, the i2c driver usage is being
converted to platform driver usage all around.

Signed-off-by: Laszlo Papp <lpapp@xxxxxxx>
---
This patch has been compile tested only and will be tested with real hardware,
but early reviews to catch any trivial issues would be welcome.
drivers/hwmon/Kconfig | 2 +-
drivers/hwmon/max6650.c | 155 ++++++++++++++++++++++++------------------------
2 files changed, 79 insertions(+), 78 deletions(-)

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 5ce43d8..48be395 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -926,7 +926,7 @@ config SENSORS_MAX6642

config SENSORS_MAX6650
tristate "Maxim MAX6650 sensor chip"
- depends on I2C
+ depends on MFD_MAX665X
help
If you say yes here you get support for the MAX6650 / MAX6651
sensor chips.
diff --git a/drivers/hwmon/max6650.c b/drivers/hwmon/max6650.c
index 0cafc39..7dbd60d 100644
--- a/drivers/hwmon/max6650.c
+++ b/drivers/hwmon/max6650.c
@@ -39,6 +39,9 @@
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
+#include <linux/platform_device.h>
+
+#include <linux/mfd/max665x-private.h>

/*
* Insmod parameters
@@ -105,24 +108,23 @@ module_param(clock, int, S_IRUGO);

#define DIV_FROM_REG(reg) (1 << (reg & 7))

-static int max6650_probe(struct i2c_client *client,
- const struct i2c_device_id *id);
-static int max6650_init_client(struct i2c_client *client);
-static int max6650_remove(struct i2c_client *client);
+static int max6650_probe(struct platform_device *pdev);
+static int max6650_init_client(struct platform_device *pdev);
+static int max6650_remove(struct platform_device *pdev);
static struct max6650_data *max6650_update_device(struct device *dev);

/*
* Driver data (common to all clients)
*/

-static const struct i2c_device_id max6650_id[] = {
+static const struct platform_device_id max6650_id[] = {
{ "max6650", 1 },
{ "max6651", 4 },
{ }
};
-MODULE_DEVICE_TABLE(i2c, max6650_id);
+MODULE_DEVICE_TABLE(platform, max6650_id);

-static struct i2c_driver max6650_driver = {
+static struct platform_driver max6650_driver = {
.driver = {
.name = "max6650",
},
@@ -137,18 +139,19 @@ static struct i2c_driver max6650_driver = {

struct max6650_data {
struct device *hwmon_dev;
+ struct max665x_dev *iodev;
struct mutex update_lock;
int nr_fans;
char valid; /* zero until following fields are valid */
unsigned long last_updated; /* in jiffies */

/* register values */
- u8 speed;
- u8 config;
- u8 tach[4];
- u8 count;
- u8 dac;
- u8 alarm;
+ int speed;
+ int config;
+ int tach[4];
+ int count;
+ int dac;
+ int alarm;
};

static ssize_t get_fan(struct device *dev, struct device_attribute *devattr,
@@ -235,8 +238,7 @@ static ssize_t get_target(struct device *dev, struct device_attribute *devattr,
static ssize_t set_target(struct device *dev, struct device_attribute *devattr,
const char *buf, size_t count)
{
- struct i2c_client *client = to_i2c_client(dev);
- struct max6650_data *data = i2c_get_clientdata(client);
+ struct max6650_data *data = dev_get_drvdata(dev);
int kscale, ktach;
unsigned long rpm;
int err;
@@ -264,7 +266,7 @@ static ssize_t set_target(struct device *dev, struct device_attribute *devattr,
ktach = 255;
data->speed = ktach;

- i2c_smbus_write_byte_data(client, MAX6650_REG_SPEED, data->speed);
+ regmap_write(data->iodev->map, MAX6650_REG_SPEED, data->speed);

mutex_unlock(&data->update_lock);

@@ -304,8 +306,7 @@ static ssize_t get_pwm(struct device *dev, struct device_attribute *devattr,
static ssize_t set_pwm(struct device *dev, struct device_attribute *devattr,
const char *buf, size_t count)
{
- struct i2c_client *client = to_i2c_client(dev);
- struct max6650_data *data = i2c_get_clientdata(client);
+ struct max6650_data *data = dev_get_drvdata(dev);
unsigned long pwm;
int err;

@@ -322,7 +323,7 @@ static ssize_t set_pwm(struct device *dev, struct device_attribute *devattr,
else
data->dac = 76 - (76 * pwm)/255;

- i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac);
+ regmap_write(data->iodev->map, MAX6650_REG_DAC, data->dac);

mutex_unlock(&data->update_lock);

@@ -350,8 +351,7 @@ static ssize_t get_enable(struct device *dev, struct device_attribute *devattr,
static ssize_t set_enable(struct device *dev, struct device_attribute *devattr,
const char *buf, size_t count)
{
- struct i2c_client *client = to_i2c_client(dev);
- struct max6650_data *data = i2c_get_clientdata(client);
+ struct max6650_data *data = dev_get_drvdata(dev);
int max6650_modes[3] = {0, 3, 2};
unsigned long mode;
int err;
@@ -365,11 +365,11 @@ static ssize_t set_enable(struct device *dev, struct device_attribute *devattr,

mutex_lock(&data->update_lock);

- data->config = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG);
+ regmap_read(data->iodev->map, MAX6650_REG_CONFIG, &data->config);
data->config = (data->config & ~MAX6650_CFG_MODE_MASK)
| (max6650_modes[mode] << 4);

- i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, data->config);
+ regmap_write(data->iodev->map, MAX6650_REG_CONFIG, data->config);

mutex_unlock(&data->update_lock);

@@ -400,8 +400,7 @@ static ssize_t get_div(struct device *dev, struct device_attribute *devattr,
static ssize_t set_div(struct device *dev, struct device_attribute *devattr,
const char *buf, size_t count)
{
- struct i2c_client *client = to_i2c_client(dev);
- struct max6650_data *data = i2c_get_clientdata(client);
+ struct max6650_data *data = dev_get_drvdata(dev);
unsigned long div;
int err;

@@ -428,7 +427,7 @@ static ssize_t set_div(struct device *dev, struct device_attribute *devattr,
return -EINVAL;
}

- i2c_smbus_write_byte_data(client, MAX6650_REG_COUNT, data->count);
+ regmap_write(data->iodev->map, MAX6650_REG_COUNT, data->count);
mutex_unlock(&data->update_lock);

return count;
@@ -445,16 +444,15 @@ static ssize_t get_alarm(struct device *dev, struct device_attribute *devattr,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
- struct max6650_data *data = max6650_update_device(dev);
- struct i2c_client *client = to_i2c_client(dev);
+ struct max6650_data *data = dev_get_drvdata(dev);
int alarm = 0;

if (data->alarm & attr->index) {
mutex_lock(&data->update_lock);
- alarm = 1;
data->alarm &= ~attr->index;
- data->alarm |= i2c_smbus_read_byte_data(client,
- MAX6650_REG_ALARM);
+ regmap_read(data->iodev->map, MAX6650_REG_ALARM, &alarm);
+ data->alarm |= alarm;
+ alarm = 1;
mutex_unlock(&data->update_lock);
}

@@ -484,10 +482,12 @@ static umode_t max6650_attrs_visible(struct kobject *kobj, struct attribute *a,
int n)
{
struct device *dev = container_of(kobj, struct device, kobj);
- struct i2c_client *client = to_i2c_client(dev);
- u8 alarm_en = i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM_EN);
+ struct max6650_data *data = dev_get_drvdata(dev);
+ int alarm_en;
struct device_attribute *devattr;

+ regmap_read(data->iodev->map, MAX6650_REG_ALARM_EN, &alarm_en);
+
/*
* Hide the alarms that have not been enabled by the firmware
*/
@@ -539,74 +539,76 @@ static const struct attribute_group max6651_attr_grp = {
* Real code
*/

-static int max6650_probe(struct i2c_client *client,
- const struct i2c_device_id *id)
+static int max6650_probe(struct platform_device *pdev)
{
+ struct max665x_dev *max665x = dev_get_drvdata(pdev->dev.parent);
struct max6650_data *data;
+ const struct platform_device_id *id = platform_get_device_id(pdev);
int err;

- data = devm_kzalloc(&client->dev, sizeof(struct max6650_data),
+ data = devm_kzalloc(&pdev->dev, sizeof(struct max6650_data),
GFP_KERNEL);
if (!data) {
- dev_err(&client->dev, "out of memory.\n");
+ dev_err(&pdev->dev, "out of memory.\n");
return -ENOMEM;
}

- i2c_set_clientdata(client, data);
+ data->iodev = max665x;
+ platform_set_drvdata(pdev, data);
mutex_init(&data->update_lock);
data->nr_fans = id->driver_data;

/*
* Initialize the max6650 chip
*/
- err = max6650_init_client(client);
+ err = max6650_init_client(pdev);
if (err)
return err;

- err = sysfs_create_group(&client->dev.kobj, &max6650_attr_grp);
+ err = sysfs_create_group(&pdev->dev.kobj, &max6650_attr_grp);
if (err)
return err;
/* 3 additional fan inputs for the MAX6651 */
if (data->nr_fans == 4) {
- err = sysfs_create_group(&client->dev.kobj, &max6651_attr_grp);
+ err = sysfs_create_group(&pdev->dev.kobj, &max6651_attr_grp);
if (err)
goto err_remove;
}

- data->hwmon_dev = hwmon_device_register(&client->dev);
+ data->hwmon_dev = hwmon_device_register(&pdev->dev);
if (!IS_ERR(data->hwmon_dev))
return 0;

err = PTR_ERR(data->hwmon_dev);
- dev_err(&client->dev, "error registering hwmon device.\n");
+ dev_err(&pdev->dev, "error registering hwmon device.\n");
if (data->nr_fans == 4)
- sysfs_remove_group(&client->dev.kobj, &max6651_attr_grp);
+ sysfs_remove_group(&pdev->dev.kobj, &max6651_attr_grp);
err_remove:
- sysfs_remove_group(&client->dev.kobj, &max6650_attr_grp);
+ sysfs_remove_group(&pdev->dev.kobj, &max6650_attr_grp);
return err;
}

-static int max6650_remove(struct i2c_client *client)
+static int max6650_remove(struct platform_device *pdev)
{
- struct max6650_data *data = i2c_get_clientdata(client);
+ struct max6650_data *data = platform_get_drvdata(pdev);

hwmon_device_unregister(data->hwmon_dev);
if (data->nr_fans == 4)
- sysfs_remove_group(&client->dev.kobj, &max6651_attr_grp);
- sysfs_remove_group(&client->dev.kobj, &max6650_attr_grp);
+ sysfs_remove_group(&pdev->dev.kobj, &max6651_attr_grp);
+ sysfs_remove_group(&pdev->dev.kobj, &max6650_attr_grp);
return 0;
}

-static int max6650_init_client(struct i2c_client *client)
+static int max6650_init_client(struct platform_device *pdev)
{
- struct max6650_data *data = i2c_get_clientdata(client);
+ struct max6650_data *data = platform_get_drvdata(pdev);
int config;
int err = -EIO;

- config = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG);
+ regmap_read(data->iodev->map, MAX6650_REG_CONFIG, &config);

if (config < 0) {
- dev_err(&client->dev, "Error reading config, aborting.\n");
+ dev_err(&pdev->dev, "Error reading config, aborting.\n");
return err;
}

@@ -620,11 +622,11 @@ static int max6650_init_client(struct i2c_client *client)
config |= MAX6650_CFG_V12;
break;
default:
- dev_err(&client->dev, "illegal value for fan_voltage (%d)\n",
+ dev_err(&pdev->dev, "illegal value for fan_voltage (%d)\n",
fan_voltage);
}

- dev_info(&client->dev, "Fan voltage is set to %dV.\n",
+ dev_info(&pdev->dev, "Fan voltage is set to %dV.\n",
(config & MAX6650_CFG_V12) ? 12 : 5);

switch (prescaler) {
@@ -650,11 +652,11 @@ static int max6650_init_client(struct i2c_client *client)
| MAX6650_CFG_PRESCALER_16;
break;
default:
- dev_err(&client->dev, "illegal value for prescaler (%d)\n",
+ dev_err(&pdev->dev, "illegal value for prescaler (%d)\n",
prescaler);
}

- dev_info(&client->dev, "Prescaler is set to %d.\n",
+ dev_info(&pdev->dev, "Prescaler is set to %d.\n",
1 << (config & MAX6650_CFG_PRESCALER_MASK));

/*
@@ -664,22 +666,22 @@ static int max6650_init_client(struct i2c_client *client)
*/

if ((config & MAX6650_CFG_MODE_MASK) == MAX6650_CFG_MODE_OFF) {
- dev_dbg(&client->dev, "Change mode to open loop, full off.\n");
+ dev_dbg(&pdev->dev, "Change mode to open loop, full off.\n");
config = (config & ~MAX6650_CFG_MODE_MASK)
| MAX6650_CFG_MODE_OPEN_LOOP;
- if (i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, 255)) {
- dev_err(&client->dev, "DAC write error, aborting.\n");
+ if (regmap_write(data->iodev->map, MAX6650_REG_DAC, 255) < 0) {
+ dev_err(&pdev->dev, "DAC write error, aborting.\n");
return err;
}
}

- if (i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, config)) {
- dev_err(&client->dev, "Config write error, aborting.\n");
+ if (regmap_write(data->iodev->map, MAX6650_REG_CONFIG, config) < 0) {
+ dev_err(&pdev->dev, "Config write error, aborting.\n");
return err;
}

data->config = config;
- data->count = i2c_smbus_read_byte_data(client, MAX6650_REG_COUNT);
+ regmap_read(data->iodev->map, MAX6650_REG_COUNT, &data->count);

return 0;
}
@@ -694,31 +696,30 @@ static const u8 tach_reg[] = {
static struct max6650_data *max6650_update_device(struct device *dev)
{
int i;
- struct i2c_client *client = to_i2c_client(dev);
- struct max6650_data *data = i2c_get_clientdata(client);
+ struct max6650_data *data = dev_get_drvdata(dev);
+ int alarm;

mutex_lock(&data->update_lock);

if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
- data->speed = i2c_smbus_read_byte_data(client,
- MAX6650_REG_SPEED);
- data->config = i2c_smbus_read_byte_data(client,
- MAX6650_REG_CONFIG);
+ regmap_read(data->iodev->map, MAX6650_REG_SPEED, &data->speed);
+ regmap_read(data->iodev->map, MAX6650_REG_CONFIG,
+ &data->config);
for (i = 0; i < data->nr_fans; i++) {
- data->tach[i] = i2c_smbus_read_byte_data(client,
- tach_reg[i]);
+ regmap_read(data->iodev->map, tach_reg[i],
+ &data->tach[i]);
}
- data->count = i2c_smbus_read_byte_data(client,
- MAX6650_REG_COUNT);
- data->dac = i2c_smbus_read_byte_data(client, MAX6650_REG_DAC);
+ regmap_read(data->iodev->map, MAX6650_REG_COUNT,
+ &data->count);
+ regmap_read(data->iodev->map, MAX6650_REG_DAC, &data->dac);

/*
* Alarms are cleared on read in case the condition that
* caused the alarm is removed. Keep the value latched here
* for providing the register through different alarm files.
*/
- data->alarm |= i2c_smbus_read_byte_data(client,
- MAX6650_REG_ALARM);
+ regmap_read(data->iodev->map, MAX6650_REG_ALARM, &alarm);
+ data->alarm |= alarm;

data->last_updated = jiffies;
data->valid = 1;
@@ -729,7 +730,7 @@ static struct max6650_data *max6650_update_device(struct device *dev)
return data;
}

-module_i2c_driver(max6650_driver);
+module_platform_driver(max6650_driver);

MODULE_AUTHOR("Hans J. Koch");
MODULE_DESCRIPTION("MAX6650 sensor driver");
--
1.8.5.4

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