[Intel-gfx] [RFC Patch 3/3] DRM/I915: Use the child device to decide whether the given DP should be intialized

[Jesse Barnes]

Same comments from the HDMI patch apply here.

On Fri,  7 Aug 2009 10:55:19 +0800
yakui.zhao at intel.com wrote:

> From: Zhao Yakui <yakui.zhao at intel.com>
> 
> Use the child device array to decide whether the given DP output
> should be initialized. If the given DP port can't be found in child
> device array, it is not present and won't be initialized.
> 
> Signed-off-by: Zhao Yakui <yakui.zhao at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_dp.c |   46
> ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 46
> insertions(+)
> 
> Index: linux-2.6/drivers/gpu/drm/i915/intel_dp.c
> ===================================================================
> --- linux-2.6.orig/drivers/gpu/drm/i915/intel_dp.c	2009-08-07
> 10:46:25.000000000 +0800 +++
> linux-2.6/drivers/gpu/drm/i915/intel_dp.c	2009-08-07
> 10:49:15.000000000 +0800 @@ -35,6 +35,11 @@ #include "i915_drv.h"
>  #include "intel_dp.h"
>  
> +#define INT_DP_CLASS	0x68C6
> +#define PORT_IDPB	0x7
> +#define PORT_IDPC	0x8
> +#define PORT_IDPD	0x9
> +
>  #define DP_LINK_STATUS_SIZE	6
>  #define DP_LINK_CHECK_TIMEOUT	(10 * 1000)
>  
> @@ -1227,7 +1232,44 @@
>  	if (dp_priv->dpms_mode == DRM_MODE_DPMS_ON)
>  		intel_dp_check_link_status(intel_output);
>  }
> +/*
> + * Enumerate the child dev array parsed from VBT to check whether
> + * the given DP is present.
> + * If it is present, return 1.
> + * If it is not present, return false.
> + * If no child dev is parsed from VBT, it assumes that the given
> + * DP is present.
> + */
> +int dp_is_present_in_vbt(struct drm_device *dev, int dp_reg)
> +{
> +	struct drm_i915_private *dev_priv = dev->dev_private;
> +	struct child_device_config *p_child;
> +	int i, dp_port, ret;
> +
> +	if (!dev_priv->child_dev_num)
> +		return 1;
>  
> +	if (dp_reg == DP_B)
> +		dp_port = PORT_IDPB;
> +	else if (dp_reg == DP_C)
> +		dp_port = PORT_IDPC;
> +	else
> +		dp_port = PORT_IDPD;
> +
> +	ret = 0;
> +	for (i = 0; i < dev_priv->child_dev_num; i++) {
> +		p_child = dev_priv->child_dev + i;
> +		/*
> +		 * If the device type is not HDMI, continue.
> +		 */
> +		if (p_child->device_type != INT_DP_CLASS)
> +			continue;
> +		/* Find the DP port */
> +		if (p_child->dvo_port == dp_port)
> +			ret = 1;
> +	}
> +	return ret;
> +}
>  void
>  intel_dp_init(struct drm_device *dev, int output_reg)
>  {
> @@ -1237,6 +1279,10 @@
>  	struct intel_dp_priv *dp_priv;
>  	const char *name = NULL;
>  
> +	if (!dp_is_present_in_vbt(dev, output_reg)) {
> +		DRM_DEBUG("DP is not present. Ignore it\n");
> +		return;
> +	}
>  	intel_output = kcalloc(sizeof(struct intel_output) + 
>  			       sizeof(struct intel_dp_priv), 1,
> GFP_KERNEL); if (!intel_output)
> 


-- 
Jesse Barnes, Intel Open Source Technology Center