Re: [PATCH] drm/panel: novatek,nt39016: Remove 'dev' field in priv struct

[Sam Ravnborg]

Hi Paul.

On Wed, Aug 19, 2020 at 08:14:12PM +0200, Paul Cercueil wrote:
> There is already a 'struct device' pointer in the drm_panel structure,
> that we can access easily from our priv structure, so there's no need
> for a separate 'dev' field there.
> 
> This also allows drm_panel_of_backlight() to work properly, as it
> requires the drm_panel.dev field to be initialized.
> 
> Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/panel/panel-novatek-nt39016.c | 11 +++++------
>  1 file changed, 5 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panel/panel-novatek-nt39016.c b/drivers/gpu/drm/panel/panel-novatek-nt39016.c
> index 39f7be679da5..292ad1d58313 100644
> --- a/drivers/gpu/drm/panel/panel-novatek-nt39016.c
> +++ b/drivers/gpu/drm/panel/panel-novatek-nt39016.c
> @@ -56,7 +56,6 @@ struct nt39016_panel_info {
>  
>  struct nt39016 {
>  	struct drm_panel drm_panel;
> -	struct device *dev;
>  	struct regmap *map;
>  	struct regulator *supply;
>  	const struct nt39016_panel_info *panel_info;
> @@ -124,7 +123,7 @@ static int nt39016_prepare(struct drm_panel *drm_panel)
>  
>  	err = regulator_enable(panel->supply);
>  	if (err) {
> -		dev_err(panel->dev, "Failed to enable power supply: %d\n", err);
> +		dev_err(drm_panel->dev, "Failed to enable power supply: %d\n", err);
>  		return err;
>  	}
>  
> @@ -143,7 +142,7 @@ static int nt39016_prepare(struct drm_panel *drm_panel)
>  	err = regmap_multi_reg_write(panel->map, nt39016_panel_regs,
>  				     ARRAY_SIZE(nt39016_panel_regs));
>  	if (err) {
> -		dev_err(panel->dev, "Failed to init registers: %d\n", err);
> +		dev_err(drm_panel->dev, "Failed to init registers: %d\n", err);
>  		goto err_disable_regulator;
>  	}
>  
> @@ -173,7 +172,7 @@ static int nt39016_enable(struct drm_panel *drm_panel)
>  	ret = regmap_write(panel->map, NT39016_REG_SYSTEM,
>  			   NT39016_SYSTEM_RESET_N | NT39016_SYSTEM_STANDBY);
>  	if (ret) {
> -		dev_err(panel->dev, "Unable to enable panel: %d\n", ret);
> +		dev_err(drm_panel->dev, "Unable to enable panel: %d\n", ret);
>  		return ret;
>  	}
>  
> @@ -193,7 +192,7 @@ static int nt39016_disable(struct drm_panel *drm_panel)
>  	err = regmap_write(panel->map, NT39016_REG_SYSTEM,
>  			   NT39016_SYSTEM_RESET_N);
>  	if (err) {
> -		dev_err(panel->dev, "Unable to disable panel: %d\n", err);
> +		dev_err(drm_panel->dev, "Unable to disable panel: %d\n", err);
>  		return err;
>  	}
>  
> @@ -252,7 +251,7 @@ static int nt39016_probe(struct spi_device *spi)
>  	if (!panel)
>  		return -ENOMEM;
>  
> -	panel->dev = dev;
> +	panel->drm_panel.dev = dev;
This is wrong. You need to fix when drm_panel_of_backlight is called.
>From drm_panel.c:
* drm_panel_of_backlight() must be called after the call to drm_panel_init().

Then the assignment can go away.

	Sam

>  	spi_set_drvdata(spi, panel);
>  
>  	panel->panel_info = of_device_get_match_data(dev);
> -- 
> 2.28.0