Commit dcbd5dcc authored by Dmitry Baryshkov's avatar Dmitry Baryshkov
Browse files

drm/panel: make prepare/enable and disable/unprepare calls return void 



Now there are no users of the return value of the drm_panel_prepare(),
drm_panel_unprepare(), drm_panel_enable() and drm_panel_disable() calls.
Usually these calls are performed from the atomic callbacks, where it is
impossible to return an error. Stop returning error codes and return
void instead.

Reviewed-by: default avatarNeil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20250401-panel-return-void-v1-7-93e1be33dc8d@oss.qualcomm.com


Signed-off-by: default avatarDmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
parent 58a71d2b

drivers/gpu/drm/drm_panel.c

+20 −34
Original line number Diff line number Diff line
@@ -106,21 +106,21 @@ EXPORT_SYMBOL(drm_panel_remove); 
 *

 * Calling this function will enable power and deassert any reset signals to

 * the panel. After this has completed it is possible to communicate with any

 * integrated circuitry via a command bus.

 *

 * Return: 0 on success or a negative error code on failure.

 * integrated circuitry via a command bus. This function cannot fail (as it is

 * called from the pre_enable call chain). There will always be a call to

 * drm_panel_disable() afterwards.

 */

int drm_panel_prepare(struct drm_panel *panel)

void drm_panel_prepare(struct drm_panel *panel)

{

	struct drm_panel_follower *follower;

	int ret;



	if (!panel)

		return -EINVAL;

		return;



	if (panel->prepared) {

		dev_warn(panel->dev, "Skipping prepare of already prepared panel\n");

		return 0;

		return;

	}



	mutex_lock(&panel->follower_lock);
@@ -139,11 +139,8 @@ int drm_panel_prepare(struct drm_panel *panel) 
				 follower->funcs->panel_prepared, ret);

	}



	ret = 0;

exit:

	mutex_unlock(&panel->follower_lock);



	return ret;

}

EXPORT_SYMBOL(drm_panel_prepare);
@@ -155,16 +152,14 @@ EXPORT_SYMBOL(drm_panel_prepare); 
 * reset, turn off power supplies, ...). After this function has completed, it

 * is usually no longer possible to communicate with the panel until another

 * call to drm_panel_prepare().

 *

 * Return: 0 on success or a negative error code on failure.

 */

int drm_panel_unprepare(struct drm_panel *panel)

void drm_panel_unprepare(struct drm_panel *panel)

{

	struct drm_panel_follower *follower;

	int ret;



	if (!panel)

		return -EINVAL;

		return;



	/*

	 * If you are seeing the warning below it likely means one of two things:
@@ -177,7 +172,7 @@ int drm_panel_unprepare(struct drm_panel *panel) 
	 */

	if (!panel->prepared) {

		dev_warn(panel->dev, "Skipping unprepare of already unprepared panel\n");

		return 0;

		return;

	}



	mutex_lock(&panel->follower_lock);
@@ -196,11 +191,8 @@ int drm_panel_unprepare(struct drm_panel *panel) 
	}

	panel->prepared = false;



	ret = 0;

exit:

	mutex_unlock(&panel->follower_lock);



	return ret;

}

EXPORT_SYMBOL(drm_panel_unprepare);
@@ -210,26 +202,26 @@ EXPORT_SYMBOL(drm_panel_unprepare); 
 *

 * Calling this function will cause the panel display drivers to be turned on

 * and the backlight to be enabled. Content will be visible on screen after

 * this call completes.

 *

 * Return: 0 on success or a negative error code on failure.

 * this call completes. This function cannot fail (as it is called from the

 * enable call chain). There will always be a call to drm_panel_disable()

 * afterwards.

 */

int drm_panel_enable(struct drm_panel *panel)

void drm_panel_enable(struct drm_panel *panel)

{

	int ret;



	if (!panel)

		return -EINVAL;

		return;



	if (panel->enabled) {

		dev_warn(panel->dev, "Skipping enable of already enabled panel\n");

		return 0;

		return;

	}



	if (panel->funcs && panel->funcs->enable) {

		ret = panel->funcs->enable(panel);

		if (ret < 0)

			return ret;

			return;

	}

	panel->enabled = true;
@@ -237,8 +229,6 @@ int drm_panel_enable(struct drm_panel *panel) 
	if (ret < 0)

		DRM_DEV_INFO(panel->dev, "failed to enable backlight: %d\n",

			     ret);



	return 0;

}

EXPORT_SYMBOL(drm_panel_enable);
@@ -249,15 +239,13 @@ EXPORT_SYMBOL(drm_panel_enable); 
 * This will typically turn off the panel's backlight or disable the display

 * drivers. For smart panels it should still be possible to communicate with

 * the integrated circuitry via any command bus after this call.

 *

 * Return: 0 on success or a negative error code on failure.

 */

int drm_panel_disable(struct drm_panel *panel)

void drm_panel_disable(struct drm_panel *panel)

{

	int ret;



	if (!panel)

		return -EINVAL;

		return;



	/*

	 * If you are seeing the warning below it likely means one of two things:
@@ -270,7 +258,7 @@ int drm_panel_disable(struct drm_panel *panel) 
	 */

	if (!panel->enabled) {

		dev_warn(panel->dev, "Skipping disable of already disabled panel\n");

		return 0;

		return;

	}



	ret = backlight_disable(panel->backlight);
@@ -281,11 +269,9 @@ int drm_panel_disable(struct drm_panel *panel) 
	if (panel->funcs && panel->funcs->disable) {

		ret = panel->funcs->disable(panel);

		if (ret < 0)

			return ret;

			return;

	}

	panel->enabled = false;



	return 0;

}

EXPORT_SYMBOL(drm_panel_disable);

drivers/gpu/drm/panel/panel-newvision-nv3051d.c

+2 −7
Original line number Diff line number Diff line
@@ -413,15 +413,10 @@ static int panel_nv3051d_probe(struct mipi_dsi_device *dsi) 
static void panel_nv3051d_shutdown(struct mipi_dsi_device *dsi)

{

	struct panel_nv3051d *ctx = mipi_dsi_get_drvdata(dsi);

	int ret;



	ret = drm_panel_unprepare(&ctx->panel);

	if (ret < 0)

		dev_err(&dsi->dev, "Failed to unprepare panel: %d\n", ret);

	drm_panel_unprepare(&ctx->panel);



	ret = drm_panel_disable(&ctx->panel);

	if (ret < 0)

		dev_err(&dsi->dev, "Failed to disable panel: %d\n", ret);

	drm_panel_disable(&ctx->panel);

}



static void panel_nv3051d_remove(struct mipi_dsi_device *dsi)

include/drm/drm_panel.h

+4 −4
Original line number Diff line number Diff line
@@ -316,11 +316,11 @@ void drm_panel_put(struct drm_panel *panel); 
void drm_panel_add(struct drm_panel *panel);

void drm_panel_remove(struct drm_panel *panel);



int drm_panel_prepare(struct drm_panel *panel);

int drm_panel_unprepare(struct drm_panel *panel);

void drm_panel_prepare(struct drm_panel *panel);

void drm_panel_unprepare(struct drm_panel *panel);



int drm_panel_enable(struct drm_panel *panel);

int drm_panel_disable(struct drm_panel *panel);

void drm_panel_enable(struct drm_panel *panel);

void drm_panel_disable(struct drm_panel *panel);



int drm_panel_get_modes(struct drm_panel *panel, struct drm_connector *connector);