Re: [PATCH v3 4/4] drm/bridge: ti-sn65dsi83: Add vcc supply regulator support

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Alexander,

Thank you for the patch.

On Tue, Oct 19, 2021 at 08:52:39AM +0200, Alexander Stein wrote:
> VCC needs to be enabled before releasing the enable GPIO.
> 
> Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
> Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> ---
>  drivers/gpu/drm/bridge/ti-sn65dsi83.c | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi83.c b/drivers/gpu/drm/bridge/ti-sn65dsi83.c
> index 9072342566f3..c55c45d5d29a 100644
> --- a/drivers/gpu/drm/bridge/ti-sn65dsi83.c
> +++ b/drivers/gpu/drm/bridge/ti-sn65dsi83.c
> @@ -33,6 +33,7 @@
>  #include <linux/of_device.h>
>  #include <linux/of_graph.h>
>  #include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
>  
>  #include <drm/drm_atomic_helper.h>
>  #include <drm/drm_bridge.h>
> @@ -143,6 +144,7 @@ struct sn65dsi83 {
>  	struct mipi_dsi_device		*dsi;
>  	struct drm_bridge		*panel_bridge;
>  	struct gpio_desc		*enable_gpio;
> +	struct regulator		*vcc;
>  	int				dsi_lanes;
>  	bool				lvds_dual_link;
>  	bool				lvds_dual_link_even_odd_swap;
> @@ -292,6 +294,11 @@ static void sn65dsi83_atomic_pre_enable(struct drm_bridge *bridge,
>  					struct drm_bridge_state *old_bridge_state)
>  {
>  	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
> +	int ret;
> +
> +	ret = regulator_enable(ctx->vcc);
> +	if (ret)
> +		dev_err(ctx->dev, "Failed to enable vcc: %i\n", ret);
>  
>  	/*
>  	 * Reset the chip, pull EN line low for t_reset=10ms,
> @@ -536,9 +543,14 @@ static void sn65dsi83_atomic_post_disable(struct drm_bridge *bridge,
>  					  struct drm_bridge_state *old_bridge_state)
>  {
>  	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
> +	int ret;
>  
>  	/* Put the chip in reset, pull EN line low. */
>  	gpiod_set_value(ctx->enable_gpio, 0);
> +
> +	ret = regulator_disable(ctx->vcc);
> +	if (ret)
> +		dev_err(ctx->dev, "Failed to disable vcc: %i\n", ret);
>  }
>  
>  static enum drm_mode_status
> @@ -647,6 +659,12 @@ static int sn65dsi83_parse_dt(struct sn65dsi83 *ctx, enum sn65dsi83_model model)
>  
>  	ctx->panel_bridge = panel_bridge;
>  
> +	ctx->vcc = devm_regulator_get(dev, "vcc");
> +	if (IS_ERR(ctx->vcc))
> +		return dev_err_probe(dev, PTR_ERR(ctx->vcc),
> +				     "Failed to get supply 'vcc': %pe\n",
> +				     ctx->vcc);
> +
>  	return 0;
>  }
>  

-- 
Regards,

Laurent Pinchart