[Intel-gfx] [RFC PATCH 03/10] drm/i915/dsi: refactor dsi get hw state readout

[Ville Syrjälä]

On Tue, Mar 15, 2016 at 09:51:11PM +0200, Jani Nikula wrote:
> Make the code easier to read and update. No functional changes.
> 
> Signed-off-by: Jani Nikula <jani.nikula at intel.com>

The logic looks intact
Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

> ---
>  drivers/gpu/drm/i915/intel_dsi.c | 37 +++++++++++++++++++------------------
>  1 file changed, 19 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
> index 01b8e9f4c272..6574b9ac3698 100644
> --- a/drivers/gpu/drm/i915/intel_dsi.c
> +++ b/drivers/gpu/drm/i915/intel_dsi.c
> @@ -667,7 +667,7 @@ static bool intel_dsi_get_hw_state(struct intel_encoder *encoder,
>  	struct drm_device *dev = encoder->base.dev;
>  	enum intel_display_power_domain power_domain;
>  	enum port port;
> -	bool ret;
> +	bool active = false;
>  
>  	DRM_DEBUG_KMS("\n");
>  
> @@ -675,38 +675,39 @@ static bool intel_dsi_get_hw_state(struct intel_encoder *encoder,
>  	if (!intel_display_power_get_if_enabled(dev_priv, power_domain))
>  		return false;
>  
> -	ret = false;
> -
>  	/* XXX: this only works for one DSI output */
>  	for_each_dsi_port(port, intel_dsi->ports) {
>  		i915_reg_t ctrl_reg = IS_BROXTON(dev) ?
>  			BXT_MIPI_PORT_CTRL(port) : MIPI_PORT_CTRL(port);
> -		u32 dpi_enabled, func;
> -
> -		func = I915_READ(MIPI_DSI_FUNC_PRG(port));
> -		dpi_enabled = I915_READ(ctrl_reg) & DPI_ENABLE;
> +		bool enabled = I915_READ(ctrl_reg) & DPI_ENABLE;
>  
>  		/* Due to some hardware limitations on BYT, MIPI Port C DPI
>  		 * Enable bit does not get set. To check whether DSI Port C
>  		 * was enabled in BIOS, check the Pipe B enable bit
>  		 */
>  		if (IS_VALLEYVIEW(dev) && port == PORT_C)
> -			dpi_enabled = I915_READ(PIPECONF(PIPE_B)) &
> -							PIPECONF_ENABLE;
> +			enabled = I915_READ(PIPECONF(PIPE_B)) & PIPECONF_ENABLE;
>  
> -		if (dpi_enabled || (func & CMD_MODE_DATA_WIDTH_MASK)) {
> -			if (I915_READ(MIPI_DEVICE_READY(port)) & DEVICE_READY) {
> -				*pipe = port == PORT_A ? PIPE_A : PIPE_B;
> -				ret = true;
> -
> -				goto out;
> -			}
> +		/* Try command mode if video mode not enabled */
> +		if (!enabled) {
> +			u32 tmp = I915_READ(MIPI_DSI_FUNC_PRG(port));
> +			enabled = tmp & CMD_MODE_DATA_WIDTH_MASK;
>  		}
> +
> +		if (!enabled)
> +			continue;
> +
> +		if (!(I915_READ(MIPI_DEVICE_READY(port)) & DEVICE_READY))
> +			continue;
> +
> +		*pipe = port == PORT_A ? PIPE_A : PIPE_B;
> +		active = true;
> +		break;
>  	}
> -out:
> +
>  	intel_display_power_put(dev_priv, power_domain);
>  
> -	return ret;
> +	return active;
>  }
>  
>  static void intel_dsi_get_config(struct intel_encoder *encoder,
> -- 
> 2.1.4

-- 
Ville Syrjälä
Intel OTC