drm/panel: Remove drm_panel_detach() calls from all panel drivers

Remove all drm_panel_detach() calls from all panel drivers and update
the kerneldoc for drm_panel_detach().

Setting the connector and drm to NULL when the DRM panel device is going
away hardly serves any purpose. Usually the whole memory structure is
freed right after the remove call. However, calling the detach function
from the master DRM device, and setting the connector pointer to NULL,
has the logic of marking the panel again as available for another DRM
master to attach. The usual situation would be the same DRM master
device binding again.

Signed-off-by: Jyri Sarha <jsarha@ti.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/464b8d330d6b4c94cfb5aad2ca9ea7eb2c52d934.1524727888.git.jsarha@ti.com

10 files changed, 6 insertions, 9 deletions

diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
index 308d442a531b..71e407574276 100644
--- a/drivers/gpu/drm/drm_panel.c
+++ b/drivers/gpu/drm/drm_panel.c
@@ -94,6 +94,9 @@ EXPORT_SYMBOL(drm_panel_remove);
  *
  * An error is returned if the panel is already attached to another connector.
  *
+ * When unloading, the driver should detach from the panel by calling
+ * drm_panel_detach().
+ *
  * Return: 0 on success or a negative error code on failure.
  */
 int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector)
@@ -115,6 +118,9 @@ EXPORT_SYMBOL(drm_panel_attach);
  * Detaches a panel from the connector it is attached to. If a panel is not
  * attached to any connector this is effectively a no-op.
  *
+ * This function should not be called by the panel device itself. It
+ * is only for the drm device that called drm_panel_attach().
+ *
  * Return: 0 on success or a negative error code on failure.
  */
 int drm_panel_detach(struct drm_panel *panel)
diff --git a/drivers/gpu/drm/panel/panel-innolux-p079zca.c b/drivers/gpu/drm/panel/panel-innolux-p079zca.c
index 57df39b5c589..bb53e0850764 100644
--- a/drivers/gpu/drm/panel/panel-innolux-p079zca.c
+++ b/drivers/gpu/drm/panel/panel-innolux-p079zca.c
@@ -292,7 +292,6 @@ static int innolux_panel_remove(struct mipi_dsi_device *dsi)
 		DRM_DEV_ERROR(&dsi->dev, "failed to detach from DSI host: %d\n",
 			      err);
 
-	drm_panel_detach(&innolux->base);
 	innolux_panel_del(innolux);
 
 	return 0;
diff --git a/drivers/gpu/drm/panel/panel-jdi-lt070me05000.c b/drivers/gpu/drm/panel/panel-jdi-lt070me05000.c
index 0a94ab79a6c0..99caa7835e7b 100644
--- a/drivers/gpu/drm/panel/panel-jdi-lt070me05000.c
+++ b/drivers/gpu/drm/panel/panel-jdi-lt070me05000.c
@@ -500,7 +500,6 @@ static int jdi_panel_remove(struct mipi_dsi_device *dsi)
 		dev_err(&dsi->dev, "failed to detach from DSI host: %d\n",
 			ret);
 
-	drm_panel_detach(&jdi->base);
 	jdi_panel_del(jdi);
 
 	return 0;
diff --git a/drivers/gpu/drm/panel/panel-lvds.c b/drivers/gpu/drm/panel/panel-lvds.c
index 5185819c5b79..8a1687887ae9 100644
--- a/drivers/gpu/drm/panel/panel-lvds.c
+++ b/drivers/gpu/drm/panel/panel-lvds.c
@@ -282,7 +282,6 @@ static int panel_lvds_remove(struct platform_device *pdev)
 {
 	struct panel_lvds *lvds = dev_get_drvdata(&pdev->dev);
 
-	drm_panel_detach(&lvds->panel);
 	drm_panel_remove(&lvds->panel);
 
 	panel_lvds_disable(&lvds->panel);
diff --git a/drivers/gpu/drm/panel/panel-panasonic-vvx10f034n00.c b/drivers/gpu/drm/panel/panel-panasonic-vvx10f034n00.c
index 74a806121f80..cb4dfb98be0f 100644
--- a/drivers/gpu/drm/panel/panel-panasonic-vvx10f034n00.c
+++ b/drivers/gpu/drm/panel/panel-panasonic-vvx10f034n00.c
@@ -299,7 +299,6 @@ static int wuxga_nt_panel_remove(struct mipi_dsi_device *dsi)
 	if (ret < 0)
 		dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", ret);
 
-	drm_panel_detach(&wuxga_nt->base);
 	wuxga_nt_panel_del(wuxga_nt);
 
 	return 0;
diff --git a/drivers/gpu/drm/panel/panel-seiko-43wvf1g.c b/drivers/gpu/drm/panel/panel-seiko-43wvf1g.c
index 71c09ed436ae..75f925390551 100644
--- a/drivers/gpu/drm/panel/panel-seiko-43wvf1g.c
+++ b/drivers/gpu/drm/panel/panel-seiko-43wvf1g.c
@@ -292,7 +292,6 @@ static int seiko_panel_remove(struct platform_device *pdev)
 {
 	struct seiko_panel *panel = dev_get_drvdata(&pdev->dev);
 
-	drm_panel_detach(&panel->base);
 	drm_panel_remove(&panel->base);
 
 	seiko_panel_disable(&panel->base);
diff --git a/drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c b/drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c
index 6bf8730f1a21..02fc0f5423d4 100644
--- a/drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c
+++ b/drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c
@@ -418,7 +418,6 @@ static int sharp_panel_remove(struct mipi_dsi_device *dsi)
 	if (err < 0)
 		dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", err);
 
-	drm_panel_detach(&sharp->base);
 	sharp_panel_del(sharp);
 
 	return 0;
diff --git a/drivers/gpu/drm/panel/panel-sharp-ls043t1le01.c b/drivers/gpu/drm/panel/panel-sharp-ls043t1le01.c
index 494aa9b1628a..e5cae0050f52 100644
--- a/drivers/gpu/drm/panel/panel-sharp-ls043t1le01.c
+++ b/drivers/gpu/drm/panel/panel-sharp-ls043t1le01.c
@@ -327,7 +327,6 @@ static int sharp_nt_panel_remove(struct mipi_dsi_device *dsi)
 	if (ret < 0)
 		dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", ret);
 
-	drm_panel_detach(&sharp_nt->base);
 	sharp_nt_panel_del(sharp_nt);
 
 	return 0;
diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
index cbf1ab404ee7..062b6b416b89 100644
--- a/drivers/gpu/drm/panel/panel-simple.c
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -364,7 +364,6 @@ static int panel_simple_remove(struct device *dev)
 {
 	struct panel_simple *panel = dev_get_drvdata(dev);
 
-	drm_panel_detach(&panel->base);
 	drm_panel_remove(&panel->base);
 
 	panel_simple_disable(&panel->base);
diff --git a/drivers/gpu/drm/panel/panel-sitronix-st7789v.c b/drivers/gpu/drm/panel/panel-sitronix-st7789v.c
index 358c64ef1922..74284e5afc5d 100644
--- a/drivers/gpu/drm/panel/panel-sitronix-st7789v.c
+++ b/drivers/gpu/drm/panel/panel-sitronix-st7789v.c
@@ -419,7 +419,6 @@ static int st7789v_remove(struct spi_device *spi)
 {
 	struct st7789v *ctx = spi_get_drvdata(spi);
 
-	drm_panel_detach(&ctx->panel);
 	drm_panel_remove(&ctx->panel);
 
 	if (ctx->backlight)