On 09/05/2014 16:16, Boris BREZILLON wrote:
> Currently, the only way to add new panel descriptions to the simple panel
> driver is to add new entries in the platform_of_match table.
>
> Add support for panel description retrieval from the DT.
>
> Signed-off-by: Boris BREZILLON <boris.brezillon at free-electrons.com>
> ---
> drivers/gpu/drm/panel/Kconfig | 1 +
> drivers/gpu/drm/panel/panel-simple.c | 70
> ++++++++++++++++++++++++++++++++++++
> 2 files changed, 71 insertions(+)
>
> diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
> index 4ec874d..4fe3d48 100644
> --- a/drivers/gpu/drm/panel/Kconfig
> +++ b/drivers/gpu/drm/panel/Kconfig
> @@ -1,6 +1,7 @@
> config DRM_PANEL
> bool
> depends on DRM
> + select VIDEOMODE_HELPERS
> help
> Panel registration and lookup framework.
>
> diff --git a/drivers/gpu/drm/panel/panel-simple.c
> b/drivers/gpu/drm/panel/panel-simple.c
> index 309f29e..fcf648d 100644
> --- a/drivers/gpu/drm/panel/panel-simple.c
> +++ b/drivers/gpu/drm/panel/panel-simple.c
> @@ -33,6 +33,10 @@
> #include <drm/drm_mipi_dsi.h>
> #include <drm/drm_panel.h>
>
> +#include <video/display_timing.h>
> +#include <video/of_display_timing.h>
> +#include <video/videomode.h>
> +
> struct panel_desc {
> const struct drm_display_mode *modes;
> unsigned int num_modes;
> @@ -168,6 +172,61 @@ static const struct drm_panel_funcs panel_simple_funcs =
> {
> .get_modes = panel_simple_get_modes,
> };
>
> +static struct panel_desc *of_panel_desc_init(struct device *dev)
> +{
> + struct display_timings *timings;
> + struct panel_desc *desc;
> + u32 width, height;
> + int err;
> + int i;
> +
> + err = of_property_read_u32(dev->of_node, "width", &width);
> + if (err)
> + return ERR_PTR(err);
> +
> + err = of_property_read_u32(dev->of_node, "height", &height);
> + if (err)
> + return ERR_PTR(err);
> +
> + desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
> + if (!desc)
> + return ERR_PTR(-ENOMEM);
> +
> + timings = of_get_display_timings(dev->of_node);
> + if (timings) {
> + struct drm_display_mode *modes =
> + devm_kzalloc(dev,
> + timings->num_timings *
> + sizeof(*desc->modes),
> + GFP_KERNEL);
> +
> + if (!modes)
> + return ERR_PTR(-ENOMEM);
> +
> + for (i = 0; i < timings->num_timings; i++) {
> + struct videomode vm;
> +
> + if (videomode_from_timings(timings, &vm, i))
> + break;
> +
> + drm_display_mode_from_videomode(&vm, modes + i);
> +
> + modes[i].type = DRM_MODE_TYPE_DRIVER;
> +
> + if (timings->native_mode == i)
> + modes[i].type |= DRM_MODE_TYPE_PREFERRED;
> + desc->num_modes++;
> + }
Oops, I forgot to add:
desc->modes = modes;
> +
> + kfree(timings);
> + }
> +
> + desc->size.width = width;
> + desc->size.height = height;
> +
> + return desc;
> +}
> +
> static int panel_simple_probe(struct device *dev, const struct panel_desc
> *desc)
> {
> struct device_node *backlight, *ddc;
> @@ -178,6 +237,17 @@ static int panel_simple_probe(struct device *dev, const
> struct panel_desc *desc)
> if (!panel)
> return -ENOMEM;
>
> + if (!desc) {
> + desc = of_panel_desc_init(dev);
> + /*
> + * Do not fail on DT panel desc retrieval error because
> + * some systems do not need a panel description to work
> + * properly.
> + */
> + if (IS_ERR(desc))
> + desc = NULL;
> + }
> +
> panel->enabled = false;
> panel->desc = desc;
>
--
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
