[PATCH] drm/bridge/synopsys: dsi: add support for non-continuous HS clock

[Neil Armstrong]

On 01/07/2020 21:42, Yannick Fertre wrote:
> From: Antonio Borneo <antonio.borneo at st.com>
> 
> Current code enables the HS clock when video mode is started or to
> send out a HS command, and disables the HS clock to send out a LP
> command. This is not what DSI spec specify.
> 
> Enable HS clock either in command and in video mode.
> Set automatic HS clock management for panels and devices that
> support non-continuous HS clock.
> 
> Signed-off-by: Antonio Borneo <antonio.borneo at st.com>
> ---
>  drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> index d580b2aa4ce9..979acaa90d00 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> @@ -365,7 +365,6 @@ static void dw_mipi_message_config(struct dw_mipi_dsi *dsi,
>  	if (lpm)
>  		val |= CMD_MODE_ALL_LP;
>  
> -	dsi_write(dsi, DSI_LPCLK_CTRL, lpm ? 0 : PHY_TXREQUESTCLKHS);
>  	dsi_write(dsi, DSI_CMD_MODE_CFG, val);
>  }
>  
> @@ -541,16 +540,22 @@ static void dw_mipi_dsi_video_mode_config(struct dw_mipi_dsi *dsi)
>  static void dw_mipi_dsi_set_mode(struct dw_mipi_dsi *dsi,
>  				 unsigned long mode_flags)
>  {
> +	u32 val;
> +
>  	dsi_write(dsi, DSI_PWR_UP, RESET);
>  
>  	if (mode_flags & MIPI_DSI_MODE_VIDEO) {
>  		dsi_write(dsi, DSI_MODE_CFG, ENABLE_VIDEO_MODE);
>  		dw_mipi_dsi_video_mode_config(dsi);
> -		dsi_write(dsi, DSI_LPCLK_CTRL, PHY_TXREQUESTCLKHS);
>  	} else {
>  		dsi_write(dsi, DSI_MODE_CFG, ENABLE_CMD_MODE);
>  	}
>  
> +	val = PHY_TXREQUESTCLKHS;
> +	if (dsi->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)
> +		val |= AUTO_CLKLANE_CTRL;
> +	dsi_write(dsi, DSI_LPCLK_CTRL, val);
> +
>  	dsi_write(dsi, DSI_PWR_UP, POWERUP);
>  }
>  
> 

Tested on Amlogic AXG (v1.21a)

Acked-by: Neil Armstrong <narmstrong at baylibre.com>

Applying to drm-misc-next

Thanks !
Neil