Re: [PATCH v2 2/2] drm/bridge: fsl-ldb: Add i.MX6SX support

[neil.armstrong@linaro.org]

On 30/03/2023 12:42, Fabio Estevam wrote:
> From: Fabio Estevam <festevam@denx.de>
> 
> i.MX6SX has a single LVDS port and share a similar LDB_CTRL register layout
> with i.MX8MP and i.MX93.
> 
> There is no LVDS CTRL register on the i.MX6SX, so only write to
> this register on the appropriate SoCs.
> 
> Add support for the i.MX6SX LDB.
> 
> Tested on a imx6sx-sdb board with a Hannstar HSD100PXN1 LVDS panel
> and also on a custom i.MX6SX-based board.
> 
> Signed-off-by: Fabio Estevam <festevam@denx.de>
> ---
> Changes since v1:
> - None
> 
>   drivers/gpu/drm/bridge/fsl-ldb.c | 14 +++++++++++++-
>   1 file changed, 13 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/bridge/fsl-ldb.c b/drivers/gpu/drm/bridge/fsl-ldb.c
> index 450b352914f4..f8e5d8ab98e3 100644
> --- a/drivers/gpu/drm/bridge/fsl-ldb.c
> +++ b/drivers/gpu/drm/bridge/fsl-ldb.c
> @@ -56,6 +56,7 @@
>   #define LVDS_CTRL_VBG_ADJ_MASK			GENMASK(19, 17)
>   
>   enum fsl_ldb_devtype {
> +	IMX6SX_LDB,
>   	IMX8MP_LDB,
>   	IMX93_LDB,
>   };
> @@ -64,9 +65,14 @@ struct fsl_ldb_devdata {
>   	u32 ldb_ctrl;
>   	u32 lvds_ctrl;
>   	bool lvds_en_bit;
> +	bool not_lvds_ctrl;
>   };
>   
>   static const struct fsl_ldb_devdata fsl_ldb_devdata[] = {
> +	[IMX6SX_LDB] = {
> +		.ldb_ctrl = 0x18,
> +		.not_lvds_ctrl = true,
> +	},
>   	[IMX8MP_LDB] = {
>   		.ldb_ctrl = 0x5c,
>   		.lvds_ctrl = 0x128,
> @@ -202,6 +208,9 @@ static void fsl_ldb_atomic_enable(struct drm_bridge *bridge,
>   
>   	regmap_write(fsl_ldb->regmap, fsl_ldb->devdata->ldb_ctrl, reg);
>   
> +	if (fsl_ldb->devdata->not_lvds_ctrl)
> +		return;
> +
>   	/* Program LVDS_CTRL */
>   	reg = LVDS_CTRL_CC_ADJ(2) | LVDS_CTRL_PRE_EMPH_EN |
>   	      LVDS_CTRL_PRE_EMPH_ADJ(3) | LVDS_CTRL_VBG_EN;
> @@ -228,7 +237,8 @@ static void fsl_ldb_atomic_disable(struct drm_bridge *bridge,
>   		regmap_write(fsl_ldb->regmap, fsl_ldb->devdata->lvds_ctrl,
>   			     LVDS_CTRL_LVDS_EN);
>   	else
> -		regmap_write(fsl_ldb->regmap, fsl_ldb->devdata->lvds_ctrl, 0);
> +		if (!fsl_ldb->devdata->not_lvds_ctrl)
> +			regmap_write(fsl_ldb->regmap, fsl_ldb->devdata->lvds_ctrl, 0);
>   	regmap_write(fsl_ldb->regmap, fsl_ldb->devdata->ldb_ctrl, 0);
>   
>   	clk_disable_unprepare(fsl_ldb->clk);
> @@ -355,6 +365,8 @@ static void fsl_ldb_remove(struct platform_device *pdev)
>   }
>   
>   static const struct of_device_id fsl_ldb_match[] = {
> +	{ .compatible = "fsl,imx6sx-ldb",
> +	  .data = &fsl_ldb_devdata[IMX6SX_LDB], },
>   	{ .compatible = "fsl,imx8mp-ldb",
>   	  .data = &fsl_ldb_devdata[IMX8MP_LDB], },
>   	{ .compatible = "fsl,imx93-ldb",

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>