Re: [PATCH 4/8] drm/bridge: fsl-ldb: Add support for i.MX94

[Frank Li <Frank.li@nxp.com>]

On Wed, Jul 09, 2025 at 03:23:23PM +0300, Laurentiu Palcu wrote:
> Since i.MX94 series LDB controller is compatible, add support for it.

Add support for the LDB controller in the i.MX94 series. Compared to i.MX93,
the i.MX94 LDB uses different register addresses for ldb_ctrl and lvds_ctrl,
and supports a higher maximum clock frequency.

Introduce max_clk_khz in the driver data to handle the frequency difference.

Frank

>
> Signed-off-by: Laurentiu Palcu <laurentiu.palcu@oss.nxp.com>
> ---
>  drivers/gpu/drm/bridge/fsl-ldb.c | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/bridge/fsl-ldb.c b/drivers/gpu/drm/bridge/fsl-ldb.c
> index 665053d0cb79d..4052e1ea9201f 100644
> --- a/drivers/gpu/drm/bridge/fsl-ldb.c
> +++ b/drivers/gpu/drm/bridge/fsl-ldb.c
> @@ -57,6 +57,7 @@ enum fsl_ldb_devtype {
>  	IMX6SX_LDB,
>  	IMX8MP_LDB,
>  	IMX93_LDB,
> +	IMX94_LDB,
>  };
>
>  struct fsl_ldb_devdata {
> @@ -64,21 +65,31 @@ struct fsl_ldb_devdata {
>  	u32 lvds_ctrl;
>  	bool lvds_en_bit;
>  	bool single_ctrl_reg;
> +	u32 max_clk_khz;
>  };
>
>  static const struct fsl_ldb_devdata fsl_ldb_devdata[] = {
>  	[IMX6SX_LDB] = {
>  		.ldb_ctrl = 0x18,
>  		.single_ctrl_reg = true,
> +		.max_clk_khz = 80000,
>  	},
>  	[IMX8MP_LDB] = {
>  		.ldb_ctrl = 0x5c,
>  		.lvds_ctrl = 0x128,
> +		.max_clk_khz = 80000,
>  	},
>  	[IMX93_LDB] = {
>  		.ldb_ctrl = 0x20,
>  		.lvds_ctrl = 0x24,
>  		.lvds_en_bit = true,
> +		.max_clk_khz = 80000,
> +	},
> +	[IMX94_LDB] = {
> +		.ldb_ctrl = 0x04,
> +		.lvds_ctrl = 0x08,
> +		.lvds_en_bit = true,
> +		.max_clk_khz = 165000,
>  	},
>  };
>
> @@ -270,8 +281,9 @@ fsl_ldb_mode_valid(struct drm_bridge *bridge,
>  		   const struct drm_display_mode *mode)
>  {
>  	struct fsl_ldb *fsl_ldb = to_fsl_ldb(bridge);
> +	u32 ch_max_clk_khz = fsl_ldb->devdata->max_clk_khz;
>
> -	if (mode->clock > (fsl_ldb_is_dual(fsl_ldb) ? 160000 : 80000))
> +	if (mode->clock > (fsl_ldb_is_dual(fsl_ldb) ? 2 * ch_max_clk_khz : ch_max_clk_khz))
>  		return MODE_CLOCK_HIGH;
>
>  	return MODE_OK;
> @@ -377,6 +389,8 @@ static const struct of_device_id fsl_ldb_match[] = {
>  	  .data = &fsl_ldb_devdata[IMX8MP_LDB], },
>  	{ .compatible = "fsl,imx93-ldb",
>  	  .data = &fsl_ldb_devdata[IMX93_LDB], },
> +	{ .compatible = "fsl,imx94-ldb",
> +	  .data = &fsl_ldb_devdata[IMX94_LDB], },
>  	{ /* sentinel */ },
>  };
>  MODULE_DEVICE_TABLE(of, fsl_ldb_match);
> --
> 2.46.1
>