Re: [PATCH 3/3] drm/mediatek: dsi: Add dsi cmdq_ctl to send panel initial code

[Matthias Brugger]

On 13/04/2023 08:09, xinlei.lee@xxxxxxxxxxxx wrote:
> From: Xinlei Lee <xinlei.lee@xxxxxxxxxxxx>
>
> For mt8188, add dsi cmdq reg control to send long packets to panel initialization.
>
> Signed-off-by: Xinlei Lee <xinlei.lee@xxxxxxxxxxxx>
> Signed-off-by: Jitao Shi <jitao.shi@xxxxxxxxxxxx>
> ---
>   drivers/gpu/drm/mediatek/mtk_dsi.c | 12 ++++++++++++
>   1 file changed, 12 insertions(+)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
> index 500a3054282d..cbfe5df4647c 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
> @@ -86,6 +86,7 @@
>   
>   #define DSI_CMDQ_SIZE		0x60
>   #define CMDQ_SIZE			0x3f
> +#define CMDQ_SIZE_SEL			BIT(15)
>   
>   #define DSI_HSTX_CKL_WC		0x64
>   
> @@ -178,6 +179,7 @@ struct mtk_dsi_driver_data {
>   	const u32 reg_cmdq_off;
>   	bool has_shadow_ctl;
>   	bool has_size_ctl;
> +	bool cmdq_long_packet_ctl;
>   };
>   
>   struct mtk_dsi {
> @@ -965,6 +967,11 @@ static u32 mtk_dsi_recv_cnt(u8 type, u8 *read_data)
>   	return 0;
>   }
>   
> +static void mtk_dsi_cmd_packet_ctl(struct mtk_dsi *dsi)
> +{
> +	mtk_dsi_mask(dsi, DSI_CMDQ_SIZE, CMDQ_SIZE_SEL, CMDQ_SIZE_SEL);
> +}
> +
>   static void mtk_dsi_cmdq(struct mtk_dsi *dsi, const struct mipi_dsi_msg *msg)
>   {
>   	const char *tx_buf = msg->tx_buf;
> @@ -996,6 +1003,8 @@ static void mtk_dsi_cmdq(struct mtk_dsi *dsi, const struct mipi_dsi_msg *msg)
>   
>   	mtk_dsi_mask(dsi, reg_cmdq_off, cmdq_mask, reg_val);
>   	mtk_dsi_mask(dsi, DSI_CMDQ_SIZE, CMDQ_SIZE, cmdq_size);
> +	if (dsi->driver_data->cmdq_long_packet_ctl)
> +		mtk_dsi_cmd_packet_ctl(dsi);

Why don't you put the onliner
mtk_dsi_mask(dsi, DSI_CMDQ_SIZE, CMDQ_SIZE_SEL, CMDQ_SIZE_SEL);
directly here. Please help me understand why adding another indirection is 
usefull here.

Best regards,
Matthias

>   }
>   
>   static ssize_t mtk_dsi_host_send_cmd(struct mtk_dsi *dsi,
> @@ -1200,18 +1209,21 @@ static const struct mtk_dsi_driver_data mt8183_dsi_driver_data = {
>   	.reg_cmdq_off = 0x200,
>   	.has_shadow_ctl = true,
>   	.has_size_ctl = true,
> +	.cmdq_long_packet_ctl = false,
>   };
>   
>   static const struct mtk_dsi_driver_data mt8186_dsi_driver_data = {
>   	.reg_cmdq_off = 0xd00,
>   	.has_shadow_ctl = true,
>   	.has_size_ctl = true,
> +	.cmdq_long_packet_ctl = false,
>   };
>   
>   static const struct mtk_dsi_driver_data mt8188_dsi_driver_data = {
>   	.reg_cmdq_off = 0xd00,
>   	.has_shadow_ctl = true,
>   	.has_size_ctl = true,
> +	.cmdq_long_packet_ctl = true,
>   };
>   
>   static const struct of_device_id mtk_dsi_of_match[] = {