[PATCH v2 1/2] drm: Improve drm_of_component_probe() to correctly handle ports and remote ports.

[Liviu Dudau]

On Fri, Nov 20, 2015 at 02:22:04PM +0000, Liviu Dudau wrote:
> Rockchip DRM driver cannot use the same compare_of() function to
> match ports and remote ports (aka encoders) as their OF sub-trees
> look different. Add a second compare function to be used when encoders
> are added to the component framework and patch the existing users of
> the function accordingly.
> 
> Signed-off-by: Liviu Dudau <Liviu.Dudau at arm.com>

Russell,

Resurecting this old patch from around Christmas time (bad time for patch review).

Are you happy enough with this version to re-issue the Ack or do you think I still
need to work on it?

Best regards,
Liviu

> ---
>  drivers/gpu/drm/armada/armada_drv.c |  3 ++-
>  drivers/gpu/drm/drm_of.c            | 19 ++++++++++++++-----
>  drivers/gpu/drm/imx/imx-drm-core.c  |  3 ++-
>  include/drm/drm_of.h                |  6 ++++--
>  4 files changed, 22 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/gpu/drm/armada/armada_drv.c b/drivers/gpu/drm/armada/armada_drv.c
> index 77ab93d..3a2a929 100644
> --- a/drivers/gpu/drm/armada/armada_drv.c
> +++ b/drivers/gpu/drm/armada/armada_drv.c
> @@ -274,7 +274,8 @@ static int armada_drm_probe(struct platform_device *pdev)
>  	struct device *dev = &pdev->dev;
>  	int ret;
>  
> -	ret = drm_of_component_probe(dev, compare_dev_name, &armada_master_ops);
> +	ret = drm_of_component_probe(dev, compare_dev_name, compare_dev_name,
> +				     &armada_master_ops);
>  	if (ret != -EINVAL)
>  		return ret;
>  
> diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c
> index 493c05c..34589d3 100644
> --- a/drivers/gpu/drm/drm_of.c
> +++ b/drivers/gpu/drm/drm_of.c
> @@ -77,7 +77,8 @@ EXPORT_SYMBOL(drm_of_find_possible_crtcs);
>   * Returns zero if successful, or one of the standard error codes if it fails.
>   */
>  int drm_of_component_probe(struct device *dev,
> -			   int (*compare_of)(struct device *, void *),
> +			   int (*compare_port)(struct device *, void *),
> +			   int (*compare_encoder)(struct device *, void *),
>  			   const struct component_master_ops *m_ops)
>  {
>  	struct device_node *ep, *port, *remote;
> @@ -101,8 +102,12 @@ int drm_of_component_probe(struct device *dev,
>  			continue;
>  		}
>  
> -		component_match_add(dev, &match, compare_of, port);
> -		of_node_put(port);
> +		component_match_add(dev, &match, compare_port, port);
> +		/*
> +		 * component_match_add keeps a reference to the port
> +		 * variable, so we need to keep the reference count
> +		 * increment from of_parse_phandle()
> +		 */
>  	}
>  
>  	if (i == 0) {
> @@ -140,8 +145,12 @@ int drm_of_component_probe(struct device *dev,
>  				continue;
>  			}
>  
> -			component_match_add(dev, &match, compare_of, remote);
> -			of_node_put(remote);
> +			component_match_add(dev, &match, compare_encoder, remote);
> +			/*
> +			 * component_match_add keeps a reference to the port
> +			 * variable, so we need to keep the reference count
> +			 * increment from of_graph_get_remote_port_parent()
> +			 */
>  		}
>  		of_node_put(port);
>  	}
> diff --git a/drivers/gpu/drm/imx/imx-drm-core.c b/drivers/gpu/drm/imx/imx-drm-core.c
> index 64f16ea..0d36410 100644
> --- a/drivers/gpu/drm/imx/imx-drm-core.c
> +++ b/drivers/gpu/drm/imx/imx-drm-core.c
> @@ -531,7 +531,8 @@ static const struct component_master_ops imx_drm_ops = {
>  
>  static int imx_drm_platform_probe(struct platform_device *pdev)
>  {
> -	int ret = drm_of_component_probe(&pdev->dev, compare_of, &imx_drm_ops);
> +	int ret = drm_of_component_probe(&pdev->dev, compare_of, compare_of,
> +					 &imx_drm_ops);
>  
>  	if (!ret)
>  		ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
> diff --git a/include/drm/drm_of.h b/include/drm/drm_of.h
> index 8544665..1c29e42 100644
> --- a/include/drm/drm_of.h
> +++ b/include/drm/drm_of.h
> @@ -10,7 +10,8 @@ struct device_node;
>  extern uint32_t drm_of_find_possible_crtcs(struct drm_device *dev,
>  					   struct device_node *port);
>  extern int drm_of_component_probe(struct device *dev,
> -				  int (*compare_of)(struct device *, void *),
> +				  int (*compare_port)(struct device *, void *),
> +				  int (*compare_encoder)(struct device *, void *),
>  				  const struct component_master_ops *m_ops);
>  #else
>  static inline uint32_t drm_of_find_possible_crtcs(struct drm_device *dev,
> @@ -21,7 +22,8 @@ static inline uint32_t drm_of_find_possible_crtcs(struct drm_device *dev,
>  
>  static inline int
>  drm_of_component_probe(struct device *dev,
> -		       int (*compare_of)(struct device *, void *),
> +		       int (*compare_port)(struct device *, void *),
> +		       int (*compare_encoder)(struct device *, void *),
>  		       const struct component_master_ops *m_ops)
>  {
>  	return -EINVAL;
> -- 
> 2.6.2
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
====================
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| fix the world,  |
| but they're not |
| giving me the   |
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