[RFC][PATCH 2/3] drm/modes: Make width-mm/height-mm mandatory in of_get_drm_panel_display_mode()

[Laurent Pinchart]

Hi Marek,

Thank you for the patch.

On Fri, Apr 01, 2022 at 06:37:54PM +0200, Marek Vasut wrote:
> Make the width-mm/height-mm panel properties mandatory in
> of_get_drm_panel_display_mode(), print error message and
> return -ve in case these DT properties are not present.
> This is needed to correctly report panel dimensions.

Can we guarantee this won't cause a regression ?

> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Christoph Niedermaier <cniedermaier at dh-electronics.com>
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> Cc: Dmitry Osipenko <digetx at gmail.com>
> Cc: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> Cc: Noralf Trønnes <noralf at tronnes.org>
> Cc: Rob Herring <robh+dt at kernel.org>
> Cc: Robert Foss <robert.foss at linaro.org>
> Cc: Sam Ravnborg <sam at ravnborg.org>
> Cc: Thomas Zimmermann <tzimmermann at suse.de>
> Cc: devicetree at vger.kernel.org
> To: dri-devel at lists.freedesktop.org
> ---
>  drivers/gpu/drm/drm_modes.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
> index 3f819c7a021b..45dc2d5c3ea6 100644
> --- a/drivers/gpu/drm/drm_modes.c
> +++ b/drivers/gpu/drm/drm_modes.c
> @@ -761,12 +761,16 @@ int of_get_drm_panel_display_mode(struct device_node *np,
>  		drm_bus_flags_from_videomode(&vm, bus_flags);
>  
>  	ret = of_property_read_u32(np, "width-mm", &width_mm);
> -	if (ret && ret != -EINVAL)
> +	if (ret < 0) {
> +		pr_err("%pOF: invalid or missing width-mm DT property\n", np);
>  		return ret;
> +	}
>  
>  	ret = of_property_read_u32(np, "height-mm", &height_mm);
> -	if (ret && ret != -EINVAL)
> +	if (ret < 0) {
> +		pr_err("%pOF: invalid or missing height-mm DT property\n", np);
>  		return ret;
> +	}
>  
>  	dmode->width_mm = width_mm;
>  	dmode->height_mm = height_mm;

-- 
Regards,

Laurent Pinchart