[PATCH] backlight: bd6107: Convert to use GPIO descriptor

[Laurent Pinchart]

Hi Linus,

Thank you for the patch.

On Mon, Dec 02, 2019 at 11:30:28AM +0100, Linus Walleij wrote:
> The Rohm BD6107 driver can pass a fixed GPIO line using the old
> GPIO API using platform data. As there are no in-tree users of this
> platform data since 2013, we can convert this to use a GPIO descriptor
> and require any out-of-tree consumers to pass the GPIO using
> a machine descriptor table instead.

Or better, converting to DT :-)

> Cc: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> Signed-off-by: Linus Walleij <linus.walleij at linaro.org>

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

How about going one step further and removing platform data support in a
second patch ?

> ---
>  drivers/video/backlight/bd6107.c     | 24 ++++++++++++++++--------
>  include/linux/platform_data/bd6107.h |  1 -
>  2 files changed, 16 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/video/backlight/bd6107.c b/drivers/video/backlight/bd6107.c
> index d344fb03cb86..d5d5fb457e78 100644
> --- a/drivers/video/backlight/bd6107.c
> +++ b/drivers/video/backlight/bd6107.c
> @@ -11,7 +11,7 @@
>  #include <linux/delay.h>
>  #include <linux/err.h>
>  #include <linux/fb.h>
> -#include <linux/gpio.h>
> +#include <linux/gpio/consumer.h>
>  #include <linux/i2c.h>
>  #include <linux/module.h>
>  #include <linux/platform_data/bd6107.h>
> @@ -71,6 +71,7 @@ struct bd6107 {
>  	struct i2c_client *client;
>  	struct backlight_device *backlight;
>  	struct bd6107_platform_data *pdata;
> +	struct gpio_desc *reset;
>  };
>  
>  static int bd6107_write(struct bd6107 *bd, u8 reg, u8 data)
> @@ -94,9 +95,10 @@ static int bd6107_backlight_update_status(struct backlight_device *backlight)
>  		bd6107_write(bd, BD6107_MAINCNT1, brightness);
>  		bd6107_write(bd, BD6107_LEDCNT1, BD6107_LEDCNT1_LEDONOFF1);
>  	} else {
> -		gpio_set_value(bd->pdata->reset, 0);
> +		/* Assert the reset line (gpiolib will handle active low) */
> +		gpiod_set_value(bd->reset, 1);
>  		msleep(24);
> -		gpio_set_value(bd->pdata->reset, 1);
> +		gpiod_set_value(bd->reset, 0);
>  	}
>  
>  	return 0;
> @@ -125,8 +127,8 @@ static int bd6107_probe(struct i2c_client *client,
>  	struct bd6107 *bd;
>  	int ret;
>  
> -	if (pdata == NULL || !pdata->reset) {
> -		dev_err(&client->dev, "No reset GPIO in platform data\n");
> +	if (pdata == NULL) {
> +		dev_err(&client->dev, "No platform data\n");
>  		return -EINVAL;
>  	}
>  
> @@ -144,10 +146,16 @@ static int bd6107_probe(struct i2c_client *client,
>  	bd->client = client;
>  	bd->pdata = pdata;
>  
> -	ret = devm_gpio_request_one(&client->dev, pdata->reset,
> -				    GPIOF_DIR_OUT | GPIOF_INIT_LOW, "reset");
> -	if (ret < 0) {
> +	/*
> +	 * Request the reset GPIO line with GPIOD_OUT_HIGH meaning asserted,
> +	 * so in the machine descriptor table (or other hardware description),
> +	 * the line should be flagged as active low so this will assert
> +	 * the reset.
> +	 */
> +	bd->reset = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_HIGH);
> +	if (IS_ERR(bd->reset)) {
>  		dev_err(&client->dev, "unable to request reset GPIO\n");
> +		ret = PTR_ERR(bd->reset);
>  		return ret;
>  	}
>  
> diff --git a/include/linux/platform_data/bd6107.h b/include/linux/platform_data/bd6107.h
> index 3bd019037eb3..54a06a4d2618 100644
> --- a/include/linux/platform_data/bd6107.h
> +++ b/include/linux/platform_data/bd6107.h
> @@ -9,7 +9,6 @@ struct device;
>  
>  struct bd6107_platform_data {
>  	struct device *fbdev;
> -	int reset;			/* Reset GPIO */
>  	unsigned int def_value;
>  };
>  

-- 
Regards,

Laurent Pinchart