[PATCHv2 08/22] drm/bridge: tc358767: split stream enable/disable

[Laurent Pinchart]

Hi Tomi,

Thank you for the patch.

On Tue, Mar 26, 2019 at 12:31:32PM +0200, Tomi Valkeinen wrote:
> It is nicer to have enable/disable functions instead of set(bool enable)
> style function.

When the two functions have nothing in common, yes.

> Split tc_main_link_stream into tc_stream_enable and tc_stream_disable.

Should you keep the tc_main_link_ prefix ? I suppose it is implied in a
way, as the stream is carried over the main link.

> Signed-off-by: Tomi Valkeinen <tomi.valkeinen at ti.com>
> ---
>  drivers/gpu/drm/bridge/tc358767.c | 81 +++++++++++++++++--------------
>  1 file changed, 45 insertions(+), 36 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
> index 86b272422281..bfc673bd5986 100644
> --- a/drivers/gpu/drm/bridge/tc358767.c
> +++ b/drivers/gpu/drm/bridge/tc358767.c
> @@ -1013,47 +1013,56 @@ static int tc_main_link_setup(struct tc_data *tc)
>  	return ret;
>  }
>  
> -static int tc_main_link_stream(struct tc_data *tc, int state)
> +static int tc_stream_enable(struct tc_data *tc)
>  {
>  	int ret;
>  	u32 value;
>  
> -	dev_dbg(tc->dev, "stream: %d\n", state);
> +	dev_dbg(tc->dev, "stream enable\n");

Maybe "enable video stream\n" (and similarly for the tc_stream_disable()
function) ?

>  
> -	if (state) {
> -		ret = tc_set_video_mode(tc, tc->mode);
> -		if (ret)
> -			goto err;
> +	ret = tc_set_video_mode(tc, tc->mode);
> +	if (ret)
> +		goto err;

Let's return ret directly and remove the err label.

With these issues addressed,

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

>  
> -		/* Set M/N */
> -		ret = tc_stream_clock_calc(tc);
> -		if (ret)
> -			goto err;
> +	/* Set M/N */
> +	ret = tc_stream_clock_calc(tc);
> +	if (ret)
> +		goto err;
>  
> -		value = VID_MN_GEN | DP_EN;
> -		if (tc->link.base.capabilities & DP_LINK_CAP_ENHANCED_FRAMING)
> -			value |= EF_EN;
> -		tc_write(DP0CTL, value);
> -		/*
> -		 * VID_EN assertion should be delayed by at least N * LSCLK
> -		 * cycles from the time VID_MN_GEN is enabled in order to
> -		 * generate stable values for VID_M. LSCLK is 270 MHz or
> -		 * 162 MHz, VID_N is set to 32768 in  tc_stream_clock_calc(),
> -		 * so a delay of at least 203 us should suffice.
> -		 */
> -		usleep_range(500, 1000);
> -		value |= VID_EN;
> -		tc_write(DP0CTL, value);
> -		/* Set input interface */
> -		value = DP0_AUDSRC_NO_INPUT;
> -		if (tc_test_pattern)
> -			value |= DP0_VIDSRC_COLOR_BAR;
> -		else
> -			value |= DP0_VIDSRC_DPI_RX;
> -		tc_write(SYSCTRL, value);
> -	} else {
> -		tc_write(DP0CTL, 0);
> -	}
> +	value = VID_MN_GEN | DP_EN;
> +	if (tc->link.base.capabilities & DP_LINK_CAP_ENHANCED_FRAMING)
> +		value |= EF_EN;
> +	tc_write(DP0CTL, value);
> +	/*
> +	 * VID_EN assertion should be delayed by at least N * LSCLK
> +	 * cycles from the time VID_MN_GEN is enabled in order to
> +	 * generate stable values for VID_M. LSCLK is 270 MHz or
> +	 * 162 MHz, VID_N is set to 32768 in  tc_stream_clock_calc(),
> +	 * so a delay of at least 203 us should suffice.
> +	 */
> +	usleep_range(500, 1000);
> +	value |= VID_EN;
> +	tc_write(DP0CTL, value);
> +	/* Set input interface */
> +	value = DP0_AUDSRC_NO_INPUT;
> +	if (tc_test_pattern)
> +		value |= DP0_VIDSRC_COLOR_BAR;
> +	else
> +		value |= DP0_VIDSRC_DPI_RX;
> +	tc_write(SYSCTRL, value);
> +
> +	return 0;
> +err:
> +	return ret;
> +}
> +
> +static int tc_stream_disable(struct tc_data *tc)
> +{
> +	int ret;
> +
> +	dev_dbg(tc->dev, "stream disable\n");
> +
> +	tc_write(DP0CTL, 0);
>  
>  	return 0;
>  err:
> @@ -1078,7 +1087,7 @@ static void tc_bridge_enable(struct drm_bridge *bridge)
>  		return;
>  	}
>  
> -	ret = tc_main_link_stream(tc, 1);
> +	ret = tc_stream_enable(tc);
>  	if (ret < 0) {
>  		dev_err(tc->dev, "main link stream start error: %d\n", ret);
>  		return;
> @@ -1094,7 +1103,7 @@ static void tc_bridge_disable(struct drm_bridge *bridge)
>  
>  	drm_panel_disable(tc->panel);
>  
> -	ret = tc_main_link_stream(tc, 0);
> +	ret = tc_stream_disable(tc);
>  	if (ret < 0)
>  		dev_err(tc->dev, "main link stream stop error: %d\n", ret);
>  }

-- 
Regards,

Laurent Pinchart