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

Lee Jones
2014-02-13T09:58:27Z

> 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@kde.org>
> ---
> 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(-)

<snip>

> /*
> * 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);

It would be good to remove these forward declarations in the future.

If no one volunteers I'll happily do it.

> /*
> * 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);

I thought you were going to do the matching in the MFD driver?

If not, what's the point in the exported 'type' attribute?

> -static struct i2c_driver max6650_driver = {
> +static struct platform_driver max6650_driver = {
> .driver = {
> .name = "max6650",

This should be changed as it now supports max665{0,1} right?

<snip>

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

Ensure all of the regmap stuff is fully tested.

<snip>

> @@ -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);
> +

Where is this then used?

> -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);

What's the point in 'type' in the global container?

It's looking as though you're not going to need it to be global after
all, right?

<snip>

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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