[PATCH v6 1/6] drm: bridge: tc358764: Use drm panel_bridge API

[Marek Szyprowski]

On 03.03.2022 17:36, Jagan Teki wrote:
> Replace the manual panel handling code by a drm panel_bridge via
> devm_drm_of_get_bridge().
>
> Adding panel_bridge handling,
>
> - Drops drm_connector and related operations as drm_bridge_attach
>    creates connector during attachment.
>
> - Drops panel pointer and panel healpers.
>
> This simplifies the driver and allows all components in the display
> pipeline to be treated as bridges.
>
> Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>

Acked-by: Marek Szyprowski <m.szyprowski at samsung.com>

Tested-by: Marek Szyprowski <m.szyprowski at samsung.com>

> ---
> Changes for v6:
> - none
> Changes for v2:
> - s/panel_bridge/next_bridge
> - drop unneeded headers
>
>   drivers/gpu/drm/bridge/tc358764.c | 104 ++----------------------------
>   1 file changed, 6 insertions(+), 98 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/tc358764.c b/drivers/gpu/drm/bridge/tc358764.c
> index c1e35bdf9232..dca41ed32f8a 100644
> --- a/drivers/gpu/drm/bridge/tc358764.c
> +++ b/drivers/gpu/drm/bridge/tc358764.c
> @@ -16,14 +16,9 @@
>   #include <video/mipi_display.h>
>   
>   #include <drm/drm_atomic_helper.h>
> -#include <drm/drm_bridge.h>
> -#include <drm/drm_crtc.h>
> -#include <drm/drm_fb_helper.h>
>   #include <drm/drm_mipi_dsi.h>
>   #include <drm/drm_of.h>
> -#include <drm/drm_panel.h>
>   #include <drm/drm_print.h>
> -#include <drm/drm_probe_helper.h>
>   
>   #define FLD_MASK(start, end)    (((1 << ((start) - (end) + 1)) - 1) << (end))
>   #define FLD_VAL(val, start, end) (((val) << (end)) & FLD_MASK(start, end))
> @@ -153,10 +148,9 @@ static const char * const tc358764_supplies[] = {
>   struct tc358764 {
>   	struct device *dev;
>   	struct drm_bridge bridge;
> -	struct drm_connector connector;
> +	struct drm_bridge *next_bridge;
>   	struct regulator_bulk_data supplies[ARRAY_SIZE(tc358764_supplies)];
>   	struct gpio_desc *gpio_reset;
> -	struct drm_panel *panel;
>   	int error;
>   };
>   
> @@ -210,12 +204,6 @@ static inline struct tc358764 *bridge_to_tc358764(struct drm_bridge *bridge)
>   	return container_of(bridge, struct tc358764, bridge);
>   }
>   
> -static inline
> -struct tc358764 *connector_to_tc358764(struct drm_connector *connector)
> -{
> -	return container_of(connector, struct tc358764, connector);
> -}
> -
>   static int tc358764_init(struct tc358764 *ctx)
>   {
>   	u32 v = 0;
> @@ -278,43 +266,11 @@ static void tc358764_reset(struct tc358764 *ctx)
>   	usleep_range(1000, 2000);
>   }
>   
> -static int tc358764_get_modes(struct drm_connector *connector)
> -{
> -	struct tc358764 *ctx = connector_to_tc358764(connector);
> -
> -	return drm_panel_get_modes(ctx->panel, connector);
> -}
> -
> -static const
> -struct drm_connector_helper_funcs tc358764_connector_helper_funcs = {
> -	.get_modes = tc358764_get_modes,
> -};
> -
> -static const struct drm_connector_funcs tc358764_connector_funcs = {
> -	.fill_modes = drm_helper_probe_single_connector_modes,
> -	.destroy = drm_connector_cleanup,
> -	.reset = drm_atomic_helper_connector_reset,
> -	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
> -	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
> -};
> -
> -static void tc358764_disable(struct drm_bridge *bridge)
> -{
> -	struct tc358764 *ctx = bridge_to_tc358764(bridge);
> -	int ret = drm_panel_disable(bridge_to_tc358764(bridge)->panel);
> -
> -	if (ret < 0)
> -		dev_err(ctx->dev, "error disabling panel (%d)\n", ret);
> -}
> -
>   static void tc358764_post_disable(struct drm_bridge *bridge)
>   {
>   	struct tc358764 *ctx = bridge_to_tc358764(bridge);
>   	int ret;
>   
> -	ret = drm_panel_unprepare(ctx->panel);
> -	if (ret < 0)
> -		dev_err(ctx->dev, "error unpreparing panel (%d)\n", ret);
>   	tc358764_reset(ctx);
>   	usleep_range(10000, 15000);
>   	ret = regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
> @@ -335,72 +291,25 @@ static void tc358764_pre_enable(struct drm_bridge *bridge)
>   	ret = tc358764_init(ctx);
>   	if (ret < 0)
>   		dev_err(ctx->dev, "error initializing bridge (%d)\n", ret);
> -	ret = drm_panel_prepare(ctx->panel);
> -	if (ret < 0)
> -		dev_err(ctx->dev, "error preparing panel (%d)\n", ret);
> -}
> -
> -static void tc358764_enable(struct drm_bridge *bridge)
> -{
> -	struct tc358764 *ctx = bridge_to_tc358764(bridge);
> -	int ret = drm_panel_enable(ctx->panel);
> -
> -	if (ret < 0)
> -		dev_err(ctx->dev, "error enabling panel (%d)\n", ret);
>   }
>   
>   static int tc358764_attach(struct drm_bridge *bridge,
>   			   enum drm_bridge_attach_flags flags)
> -{
> -	struct tc358764 *ctx = bridge_to_tc358764(bridge);
> -	struct drm_device *drm = bridge->dev;
> -	int ret;
> -
> -	if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
> -		DRM_ERROR("Fix bridge driver to make connector optional!");
> -		return -EINVAL;
> -	}
> -
> -	ctx->connector.polled = DRM_CONNECTOR_POLL_HPD;
> -	ret = drm_connector_init(drm, &ctx->connector,
> -				 &tc358764_connector_funcs,
> -				 DRM_MODE_CONNECTOR_LVDS);
> -	if (ret) {
> -		DRM_ERROR("Failed to initialize connector\n");
> -		return ret;
> -	}
> -
> -	drm_connector_helper_add(&ctx->connector,
> -				 &tc358764_connector_helper_funcs);
> -	drm_connector_attach_encoder(&ctx->connector, bridge->encoder);
> -	ctx->connector.funcs->reset(&ctx->connector);
> -	drm_connector_register(&ctx->connector);
> -
> -	return 0;
> -}
> -
> -static void tc358764_detach(struct drm_bridge *bridge)
>   {
>   	struct tc358764 *ctx = bridge_to_tc358764(bridge);
>   
> -	drm_connector_unregister(&ctx->connector);
> -	ctx->panel = NULL;
> -	drm_connector_put(&ctx->connector);
> +	return drm_bridge_attach(bridge->encoder, ctx->next_bridge, bridge, flags);
>   }
>   
>   static const struct drm_bridge_funcs tc358764_bridge_funcs = {
> -	.disable = tc358764_disable,
>   	.post_disable = tc358764_post_disable,
> -	.enable = tc358764_enable,
>   	.pre_enable = tc358764_pre_enable,
>   	.attach = tc358764_attach,
> -	.detach = tc358764_detach,
>   };
>   
>   static int tc358764_parse_dt(struct tc358764 *ctx)
>   {
>   	struct device *dev = ctx->dev;
> -	int ret;
>   
>   	ctx->gpio_reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
>   	if (IS_ERR(ctx->gpio_reset)) {
> @@ -408,12 +317,11 @@ static int tc358764_parse_dt(struct tc358764 *ctx)
>   		return PTR_ERR(ctx->gpio_reset);
>   	}
>   
> -	ret = drm_of_find_panel_or_bridge(ctx->dev->of_node, 1, 0, &ctx->panel,
> -					  NULL);
> -	if (ret && ret != -EPROBE_DEFER)
> -		dev_err(dev, "cannot find panel (%d)\n", ret);
> +	ctx->next_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 1, 0);
> +	if (IS_ERR(ctx->next_bridge))
> +		return PTR_ERR(ctx->next_bridge);
>   
> -	return ret;
> +	return 0;
>   }
>   
>   static int tc358764_configure_regulators(struct tc358764 *ctx)

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland