Re: [PATCH 1/2] drm: add plane support

[Chris Wilson <chris@chris-wilson.co.uk>]

On Tue,  8 Nov 2011 09:38:52 -0800, Jesse Barnes <jbarnes@virtuousgeek.org> wrote:
> Planes are a bit like half-CRTCs.  They have a location and fb, but
> don't drive outputs directly.  Add support for handling them to the core
> KMS code.
> 
> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
> Reviewed-by: Rob Clark <rob.clark@linaro.org>
> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
> ---
>  drivers/gpu/drm/drm_crtc.c |  251 +++++++++++++++++++++++++++++++++++++++++++-
>  drivers/gpu/drm/drm_drv.c  |    3 +
>  include/drm/drm.h          |    3 +
>  include/drm/drm_crtc.h     |   75 +++++++++++++-
>  include/drm/drm_mode.h     |   33 ++++++
>  5 files changed, 362 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
> index fe738f0..fac8043 100644
> --- a/drivers/gpu/drm/drm_crtc.c
> +++ b/drivers/gpu/drm/drm_crtc.c
> @@ -321,6 +321,7 @@ void drm_framebuffer_cleanup(struct drm_framebuffer *fb)
>  {
>  	struct drm_device *dev = fb->dev;
>  	struct drm_crtc *crtc;
> +	struct drm_plane *plane;
>  	struct drm_mode_set set;
>  	int ret;
>  
> @@ -337,6 +338,15 @@ void drm_framebuffer_cleanup(struct drm_framebuffer *fb)
>  		}
>  	}
>  
> +	list_for_each_entry(plane, &dev->mode_config.plane_list, head) {
> +		if (plane->fb == fb) {
> +			/* should turn off the crtc */
> +			ret = plane->funcs->disable_plane(plane);
> +			if (ret)
> +				DRM_ERROR("failed to disable plane with busy fb\n");
> +		}
> +	}
> +
>  	drm_mode_object_put(dev, &fb->base);
>  	list_del(&fb->head);
>  	dev->mode_config.num_fb--;
> @@ -535,6 +545,48 @@ void drm_encoder_cleanup(struct drm_encoder *encoder)
>  }
>  EXPORT_SYMBOL(drm_encoder_cleanup);
>  
> +void drm_plane_init(struct drm_device *dev, struct drm_plane *plane,
> +		    unsigned long possible_crtcs,
> +		    const struct drm_plane_funcs *funcs,
> +		    uint32_t *formats, uint32_t format_count)
> +{
> +	mutex_lock(&dev->mode_config.mutex);
> +
> +	plane->dev = dev;
> +	drm_mode_object_get(dev, &plane->base, DRM_MODE_OBJECT_PLANE);
> +	plane->funcs = funcs;
> +	plane->format_types = kmalloc(sizeof(uint32_t) * format_count,
> +				      GFP_KERNEL);
> +	if (!plane->format_types) {
> +		DRM_DEBUG_KMS("out of memory when allocating plane\n");
> +		drm_mode_object_put(dev, &plane->base);
> +		return;
This can fail, report it back to the caller so that he can tear down his
allocations and propagate onwards. Kthxbye.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre