[PATCH v23 07/14] drm/mediatek: add display merge async reset control

[CK Hu]

Hi, Nancy:

On Mon, 2022-06-20 at 17:19 +0800, Nancy.Lin wrote:
> Add merge async reset control in mtk_merge_stop. Async hw doesn't do
> self
> reset on each sof signal(start of frame), so need to reset the async
> to
> clear the hw status for the next merge start.

Applied to mediatek-drm-next [1], thanks.

[1] 
https://git.kernel.org/pub/scm/linux/kernel/git/chunkuang.hu/linux.git/log/?h=mediatek-drm-next

Regards,
CK

> 
> Signed-off-by: Nancy.Lin <nancy.lin at mediatek.com>
> Reviewed-by: CK Hu <ck.hu at mediatek.com>
> Reviewed-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno at collabora.com>
> Tested-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno at collabora.com>
> Tested-by: Bo-Chen Chen <rex-bc.chen at mediatek.com>
> ---
>  drivers/gpu/drm/mediatek/mtk_disp_merge.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_merge.c
> b/drivers/gpu/drm/mediatek/mtk_disp_merge.c
> index 2e13d2fb429e..6428b6203ffe 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_merge.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_merge.c
> @@ -8,6 +8,7 @@
>  #include <linux/of_device.h>
>  #include <linux/of_irq.h>
>  #include <linux/platform_device.h>
> +#include <linux/reset.h>
>  #include <linux/soc/mediatek/mtk-cmdq.h>
>  
>  #include "mtk_drm_ddp_comp.h"
> @@ -67,6 +68,7 @@ struct mtk_disp_merge {
>  	struct cmdq_client_reg		cmdq_reg;
>  	bool				fifo_en;
>  	bool				mute_support;
> +	struct reset_control		*reset_ctl;
>  };
>  
>  void mtk_merge_start(struct device *dev)
> @@ -101,6 +103,9 @@ void mtk_merge_stop_cmdq(struct device *dev,
> struct cmdq_pkt *cmdq_pkt)
>  
>  	mtk_ddp_write(cmdq_pkt, 0, &priv->cmdq_reg, priv->regs,
>  		      DISP_REG_MERGE_CTRL);
> +
> +	if (priv->async_clk)
> +		reset_control_reset(priv->reset_ctl);
>  }
>  
>  static void mtk_merge_fifo_setting(struct mtk_disp_merge *priv,
> @@ -264,6 +269,12 @@ static int mtk_disp_merge_probe(struct
> platform_device *pdev)
>  		return PTR_ERR(priv->async_clk);
>  	}
>  
> +	if (priv->async_clk) {
> +		priv->reset_ctl =
> devm_reset_control_get_optional_exclusive(dev, NULL);
> +		if (IS_ERR(priv->reset_ctl))
> +			return PTR_ERR(priv->reset_ctl);
> +	}
> +
>  #if IS_REACHABLE(CONFIG_MTK_CMDQ)
>  	ret = cmdq_dev_get_client_reg(dev, &priv->cmdq_reg, 0);
>  	if (ret)