[Intel-gfx] [v9 01/12] drm/i915/display: Add HDR Capability detection for LSPCON

[Ville Syrjälä]

On Tue, Nov 03, 2020 at 08:58:23PM +0530, Uma Shankar wrote:
> LSPCON firmware exposes HDR capability through LPCON_CAPABILITIES
> DPCD register. LSPCON implementations capable of supporting
> HDR set HDR_CAPABILITY bit in LSPCON_CAPABILITIES to 1. This patch
> reads the same, detects the HDR capability and adds this to
> intel_lspcon struct.
> 
> v2: Addressed Jani Nikula's review comment and fixed the HDR
>     capability detection logic
> 
> v3: Deferred HDR detection from lspcon_init (Ville)
> 
> Signed-off-by: Uma Shankar <uma.shankar at intel.com>
> ---
>  .../drm/i915/display/intel_display_types.h    |  1 +
>  drivers/gpu/drm/i915/display/intel_lspcon.c   | 28 +++++++++++++++++++
>  drivers/gpu/drm/i915/display/intel_lspcon.h   |  1 +
>  3 files changed, 30 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
> index f6f0626649e0..25b2db337174 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> @@ -1417,6 +1417,7 @@ struct intel_lspcon {
>  	bool active;
>  	enum drm_lspcon_mode mode;
>  	enum lspcon_vendor vendor;
> +	bool hdr_supported;

Can be packed next to the other bool.

>  };
>  
>  struct intel_digital_port {
> diff --git a/drivers/gpu/drm/i915/display/intel_lspcon.c b/drivers/gpu/drm/i915/display/intel_lspcon.c
> index e37d45e531df..076b21885a30 100644
> --- a/drivers/gpu/drm/i915/display/intel_lspcon.c
> +++ b/drivers/gpu/drm/i915/display/intel_lspcon.c
> @@ -35,6 +35,8 @@
>  #define LSPCON_VENDOR_PARADE_OUI 0x001CF8
>  #define LSPCON_VENDOR_MCA_OUI 0x0060AD
>  
> +#define DPCD_MCA_LSPCON_HDR_STATUS	0x70003
> +
>  /* AUX addresses to write MCA AVI IF */
>  #define LSPCON_MCA_AVI_IF_WRITE_OFFSET 0x5C0
>  #define LSPCON_MCA_AVI_IF_CTRL 0x5DF
> @@ -104,6 +106,32 @@ static bool lspcon_detect_vendor(struct intel_lspcon *lspcon)
>  	return true;
>  }
>  
> +void lspcon_detect_hdr_capability(struct intel_lspcon *lspcon)
> +{
> +	struct intel_digital_port *dig_port =
> +		container_of(lspcon, struct intel_digital_port, lspcon);
> +	struct drm_device *dev = dig_port->base.base.dev;
> +	struct intel_dp *dp = lspcon_to_intel_dp(lspcon);
> +	u8 hdr_caps;
> +	int ret;
> +
> +	/* Enable HDR for MCA based LSPCON devices */
> +	if (lspcon->vendor == LSPCON_VENDOR_MCA)
> +		ret = drm_dp_dpcd_read(&dp->aux, DPCD_MCA_LSPCON_HDR_STATUS,
> +				       &hdr_caps, 1);
> +	else
> +		return;
> +
> +	if (ret < 0) {
> +		drm_dbg_kms(dev, "hdr capability detection failed\n");

"hdr" vs. "HDR" elsewhere.

> +		lspcon->hdr_supported = false;
> +		return;

Pointless return?

> +	} else if (hdr_caps & 0x1) {
> +		drm_dbg_kms(dev, "lspcon capable of HDR\n");

"lspcon" vs. "LSPCON"

No idea about the magic dpcd reg, but otherwise seems sane enough.
Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

> +		lspcon->hdr_supported = true;
> +	}
> +}
> +
>  static enum drm_lspcon_mode lspcon_get_current_mode(struct intel_lspcon *lspcon)
>  {
>  	enum drm_lspcon_mode current_mode;
> diff --git a/drivers/gpu/drm/i915/display/intel_lspcon.h b/drivers/gpu/drm/i915/display/intel_lspcon.h
> index b03dcb7076d8..a19b3564c635 100644
> --- a/drivers/gpu/drm/i915/display/intel_lspcon.h
> +++ b/drivers/gpu/drm/i915/display/intel_lspcon.h
> @@ -15,6 +15,7 @@ struct intel_digital_port;
>  struct intel_encoder;
>  struct intel_lspcon;
>  
> +void lspcon_detect_hdr_capability(struct intel_lspcon *lspcon);
>  void lspcon_resume(struct intel_digital_port *dig_port);
>  void lspcon_wait_pcon_mode(struct intel_lspcon *lspcon);
>  void lspcon_write_infoframe(struct intel_encoder *encoder,
> -- 
> 2.26.2

-- 
Ville Syrjälä
Intel