Hi, Michael:
Michael Walle <mwalle@xxxxxxxxxx> 於 2024年6月6日 週四 下午5:22寫道：
>
> mtk_find_possible_crtcs() assumes that the main path will always have
> the CRTC with id 0, the ext id 1 and the third id 2. This is only true
> if the paths are all available. But paths are optional (see also
> comment in mtk_drm_kms_init()), e.g. the main path might not be enabled
> or available at all. Then the CRTC IDs will shift one up, e.g. ext will
> be 0 and the third path will be 1.
>
> To fix that, dynamically calculate the IDs by the presence of the paths.
>
> While at it, make the return code a signed one and return -ENODEV if no
> path is found and handle the error in the callers.
>
> Fixes: 5aa8e7647676 ("drm/mediatek: dpi/dsi: Change the getting possible_crtc way")
> Suggested-by: Nícolas F. R. A. Prado <nfraprado@xxxxxxxxxxxxx>
> Signed-off-by: Michael Walle <mwalle@xxxxxxxxxx>
> ---
> You can find v4 at [1]. Unfortunately, it was never applied and in the
> meantime there was a change in mtk_find_possible_crtcs(). So I've
> dropped Nícolas Reviewed and Tested-by tags and Angelos Reviewed-by
> tag.
>
> [1] https://lore.kernel.org/r/20230905084922.3908121-2-mwalle@xxxxxxxxxx/
> ---
> drivers/gpu/drm/mediatek/mtk_ddp_comp.c | 105 ++++++++++++++++--------
> drivers/gpu/drm/mediatek/mtk_ddp_comp.h | 2 +-
> drivers/gpu/drm/mediatek/mtk_dpi.c | 5 +-
> drivers/gpu/drm/mediatek/mtk_dsi.c | 5 +-
> 4 files changed, 78 insertions(+), 39 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_ddp_comp.c b/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
> index 17b036411292..9a8c1cace8a0 100644
> --- a/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
> +++ b/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
> @@ -514,29 +514,42 @@ static bool mtk_ddp_comp_find(struct device *dev,
> return false;
> }
>
> -static unsigned int mtk_ddp_comp_find_in_route(struct device *dev,
> - const struct mtk_drm_route *routes,
> - unsigned int num_routes,
> - struct mtk_ddp_comp *ddp_comp)
> +static int mtk_ddp_comp_find_in_route(struct device *dev,
> + const struct mtk_drm_route *routes,
> + unsigned int num_routes,
> + struct mtk_ddp_comp *ddp_comp)
> {
> - int ret;
> unsigned int i;
>
> - if (!routes) {
> - ret = -EINVAL;
> - goto err;
> - }
> + if (!routes)
> + return -EINVAL;
>
> for (i = 0; i < num_routes; i++)
> if (dev == ddp_comp[routes[i].route_ddp].dev)
> return BIT(routes[i].crtc_id);
>
> - ret = -ENODEV;
> -err:
> + return -ENODEV;
> +}
>
> - DRM_INFO("Failed to find comp in ddp table, ret = %d\n", ret);
> +static bool mtk_ddp_path_available(const unsigned int *path,
> + unsigned int path_len,
> + struct device_node **comp_node)
> +{
> + unsigned int i;
>
> - return 0;
> + if (!path || !path_len)
> + return false;
> +
> + for (i = 0U; i < path_len; i++) {
> + /* OVL_ADAPTOR doesn't have a device node */
> + if (path[i] == DDP_COMPONENT_DRM_OVL_ADAPTOR)
> + continue;
> +
> + if (!comp_node[path[i]])
> + return false;
> + }
> +
> + return true;
> }
>
> int mtk_ddp_comp_get_id(struct device_node *node,
> @@ -554,32 +567,52 @@ int mtk_ddp_comp_get_id(struct device_node *node,
> return -EINVAL;
> }
>
> -unsigned int mtk_find_possible_crtcs(struct drm_device *drm, struct device *dev)
> +int mtk_find_possible_crtcs(struct drm_device *drm, struct device *dev)
> {
> struct mtk_drm_private *private = drm->dev_private;
> - unsigned int ret = 0;
> -
> - if (mtk_ddp_comp_find(dev,
> - private->data->main_path,
> - private->data->main_len,
> - private->ddp_comp))
> - ret = BIT(0);
> - else if (mtk_ddp_comp_find(dev,
> - private->data->ext_path,
> - private->data->ext_len,
> - private->ddp_comp))
> - ret = BIT(1);
> - else if (mtk_ddp_comp_find(dev,
> - private->data->third_path,
> - private->data->third_len,
> - private->ddp_comp))
> - ret = BIT(2);
> - else
> - ret = mtk_ddp_comp_find_in_route(dev,
> - private->data->conn_routes,
> - private->data->num_conn_routes,
> - private->ddp_comp);
> + const struct mtk_mmsys_driver_data *data;
> + struct mtk_drm_private *priv_n;
> + int i = 0, j;
> + int ret;
>
> + for (j = 0; j < private->data->mmsys_dev_num; j++) {
> + priv_n = private->all_drm_private[j];
> + data = priv_n->data;
> +
> + if (mtk_ddp_path_available(data->main_path, data->main_len,
> + priv_n->comp_node)) {
> + if (mtk_ddp_comp_find(dev, data->main_path,
> + data->main_len,
> + priv_n->ddp_comp))
> + return BIT(i);
> + i++;
> + }
> +
> + if (mtk_ddp_path_available(data->ext_path, data->ext_len,
> + priv_n->comp_node)) {
> + if (mtk_ddp_comp_find(dev, data->ext_path,
> + data->ext_len,
> + priv_n->ddp_comp))
> + return BIT(i);
> + i++;
> + }
> +
> + if (mtk_ddp_path_available(data->third_path, data->third_len,
> + priv_n->comp_node)) {
> + if (mtk_ddp_comp_find(dev, data->third_path,
> + data->third_len,
> + priv_n->ddp_comp))
> + return BIT(i);
> + i++;
> + }
> + }
> +
> + ret = mtk_ddp_comp_find_in_route(dev,
> + private->data->conn_routes,
> + private->data->num_conn_routes,
> + private->ddp_comp);
> +
> + DRM_INFO("Failed to find comp in ddp table, ret = %d\n", ret);
After checking ret < 0 then print this error message, applied to
mediatek-drm-next [1], thanks.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/chunkuang.hu/linux.git/log/?h=mediatek-drm-next
Regards,
Chun-Kuang.
> return ret;
> }
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_ddp_comp.h b/drivers/gpu/drm/mediatek/mtk_ddp_comp.h
> index 26236691ce4c..e2ea19d5ddcb 100644
> --- a/drivers/gpu/drm/mediatek/mtk_ddp_comp.h
> +++ b/drivers/gpu/drm/mediatek/mtk_ddp_comp.h
> @@ -326,7 +326,7 @@ static inline void mtk_ddp_comp_encoder_index_set(struct mtk_ddp_comp *comp)
>
> int mtk_ddp_comp_get_id(struct device_node *node,
> enum mtk_ddp_comp_type comp_type);
> -unsigned int mtk_find_possible_crtcs(struct drm_device *drm, struct device *dev);
> +int mtk_find_possible_crtcs(struct drm_device *drm, struct device *dev);
> int mtk_ddp_comp_init(struct device_node *comp_node, struct mtk_ddp_comp *comp,
> unsigned int comp_id);
> enum mtk_ddp_comp_type mtk_ddp_comp_get_type(unsigned int comp_id);
> diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c b/drivers/gpu/drm/mediatek/mtk_dpi.c
> index 5c86aa0b75b2..b894be9f1f53 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dpi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dpi.c
> @@ -814,7 +814,10 @@ static int mtk_dpi_bind(struct device *dev, struct device *master, void *data)
> return ret;
> }
>
> - dpi->encoder.possible_crtcs = mtk_find_possible_crtcs(drm_dev, dpi->dev);
> + ret = mtk_find_possible_crtcs(drm_dev, dpi->dev);
> + if (ret < 0)
> + goto err_cleanup;
> + dpi->encoder.possible_crtcs = ret;
>
> ret = drm_bridge_attach(&dpi->encoder, &dpi->bridge, NULL,
> DRM_BRIDGE_ATTACH_NO_CONNECTOR);
> diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
> index 2b0ac859a653..b450b7223aa2 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
> @@ -861,7 +861,10 @@ static int mtk_dsi_encoder_init(struct drm_device *drm, struct mtk_dsi *dsi)
> return ret;
> }
>
> - dsi->encoder.possible_crtcs = mtk_find_possible_crtcs(drm, dsi->host.dev);
> + ret = mtk_find_possible_crtcs(drm, dsi->host.dev);
> + if (ret < 0)
> + goto err_cleanup_encoder;
> + dsi->encoder.possible_crtcs = ret;
>
> ret = drm_bridge_attach(&dsi->encoder, &dsi->bridge, NULL,
> DRM_BRIDGE_ATTACH_NO_CONNECTOR);
> --
> 2.39.2
>
