drm/mipi-dsi: Make remove callback return void

All implementations return 0 and the return value of mipi_dsi_drv_remove()
is ignored anyhow.

So change the prototype of the remove function to return no value. This
way driver authors are not tempted to assume that passing an error to
the upper layer is a good idea. All drivers are adapted accordingly.
There is no intended change of behaviour.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220708094922.1408248-4-u.kleine-koenig@pengutronix.de

50 files changed, 53 insertions, 146 deletions

diff --git a/drivers/gpu/drm/bridge/chipone-icn6211.c b/drivers/gpu/drm/bridge/chipone-icn6211.c
index 481c86b2406e..b07d2d16c3cf 100644
--- a/drivers/gpu/drm/bridge/chipone-icn6211.c
+++ b/drivers/gpu/drm/bridge/chipone-icn6211.c
@@ -735,14 +735,12 @@ static int chipone_i2c_probe(struct i2c_client *client,
 	return chipone_dsi_host_attach(icn);
 }
 
-static int chipone_dsi_remove(struct mipi_dsi_device *dsi)
+static void chipone_dsi_remove(struct mipi_dsi_device *dsi)
 {
 	struct chipone *icn = mipi_dsi_get_drvdata(dsi);
 
 	mipi_dsi_detach(dsi);
 	drm_bridge_remove(&icn->bridge);
-
-	return 0;
 }
 
 static const struct of_device_id chipone_of_match[] = {
diff --git a/drivers/gpu/drm/bridge/tc358762.c b/drivers/gpu/drm/bridge/tc358762.c
index 40439da4db49..7f4fce1aa998 100644
--- a/drivers/gpu/drm/bridge/tc358762.c
+++ b/drivers/gpu/drm/bridge/tc358762.c
@@ -241,14 +241,12 @@ static int tc358762_probe(struct mipi_dsi_device *dsi)
 	return ret;
 }
 
-static int tc358762_remove(struct mipi_dsi_device *dsi)
+static void tc358762_remove(struct mipi_dsi_device *dsi)
 {
 	struct tc358762 *ctx = mipi_dsi_get_drvdata(dsi);
 
 	mipi_dsi_detach(dsi);
 	drm_bridge_remove(&ctx->bridge);
-
-	return 0;
 }
 
 static const struct of_device_id tc358762_of_match[] = {
diff --git a/drivers/gpu/drm/bridge/tc358764.c b/drivers/gpu/drm/bridge/tc358764.c
index fdfb14aca926..53259c12d777 100644
--- a/drivers/gpu/drm/bridge/tc358764.c
+++ b/drivers/gpu/drm/bridge/tc358764.c
@@ -381,14 +381,12 @@ static int tc358764_probe(struct mipi_dsi_device *dsi)
 	return ret;
 }
 
-static int tc358764_remove(struct mipi_dsi_device *dsi)
+static void tc358764_remove(struct mipi_dsi_device *dsi)
 {
 	struct tc358764 *ctx = mipi_dsi_get_drvdata(dsi);
 
 	mipi_dsi_detach(dsi);
 	drm_bridge_remove(&ctx->bridge);
-
-	return 0;
 }
 
 static const struct of_device_id tc358764_of_match[] = {
diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c
index c40bde96cfdf..2e25804d6ffa 100644
--- a/drivers/gpu/drm/drm_mipi_dsi.c
+++ b/drivers/gpu/drm/drm_mipi_dsi.c
@@ -1236,7 +1236,9 @@ static int mipi_dsi_drv_remove(struct device *dev)
 	struct mipi_dsi_driver *drv = to_mipi_dsi_driver(dev->driver);
 	struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
 
-	return drv->remove(dsi);
+	drv->remove(dsi);
+
+	return 0;
 }
 
 static void mipi_dsi_drv_shutdown(struct device *dev)
diff --git a/drivers/gpu/drm/panel/panel-asus-z00t-tm5p5-n35596.c b/drivers/gpu/drm/panel/panel-asus-z00t-tm5p5-n35596.c
index 174ff434bd71..b3235781e6ba 100644
--- a/drivers/gpu/drm/panel/panel-asus-z00t-tm5p5-n35596.c
+++ b/drivers/gpu/drm/panel/panel-asus-z00t-tm5p5-n35596.c
@@ -321,7 +321,7 @@ static int tm5p5_nt35596_probe(struct mipi_dsi_device *dsi)
 	return 0;
 }
 
-static int tm5p5_nt35596_remove(struct mipi_dsi_device *dsi)
+static void tm5p5_nt35596_remove(struct mipi_dsi_device *dsi)
 {
 	struct tm5p5_nt35596 *ctx = mipi_dsi_get_drvdata(dsi);
 	int ret;
@@ -332,8 +332,6 @@ static int tm5p5_nt35596_remove(struct mipi_dsi_device *dsi)
 			"Failed to detach from DSI host: %d\n", ret);
 
 	drm_panel_remove(&ctx->panel);
-
-	return 0;
 }
 
 static const struct of_device_id tm5p5_nt35596_of_match[] = {
diff --git a/drivers/gpu/drm/panel/panel-boe-bf060y8m-aj0.c b/drivers/gpu/drm/panel/panel-boe-bf060y8m-aj0.c
index ef00cd67dc40..ad58840eda41 100644
--- a/drivers/gpu/drm/panel/panel-boe-bf060y8m-aj0.c
+++ b/drivers/gpu/drm/panel/panel-boe-bf060y8m-aj0.c
@@ -410,7 +410,7 @@ static int boe_bf060y8m_aj0_probe(struct mipi_dsi_device *dsi)
 	return 0;
 }
 
-static int boe_bf060y8m_aj0_remove(struct mipi_dsi_device *dsi)
+static void boe_bf060y8m_aj0_remove(struct mipi_dsi_device *dsi)
 {
 	struct boe_bf060y8m_aj0 *boe = mipi_dsi_get_drvdata(dsi);
 	int ret;
@@ -420,8 +420,6 @@ static int boe_bf060y8m_aj0_remove(struct mipi_dsi_device *dsi)
 		dev_err(&dsi->dev, "Failed to detach from DSI host: %d\n", ret);
 
 	drm_panel_remove(&boe->panel);
-
-	return 0;
 }
 
 static const struct of_device_id boe_bf060y8m_aj0_of_match[] = {
diff --git a/drivers/gpu/drm/panel/panel-boe-himax8279d.c b/drivers/gpu/drm/panel/panel-boe-himax8279d.c
index 42854bd37fd5..d879b3b14c48 100644
--- a/drivers/gpu/drm/panel/panel-boe-himax8279d.c
+++ b/drivers/gpu/drm/panel/panel-boe-himax8279d.c
@@ -919,7 +919,7 @@ static int panel_probe(struct mipi_dsi_device *dsi)
 	return err;
 }
 
-static int panel_remove(struct mipi_dsi_device *dsi)
+static void panel_remove(struct mipi_dsi_device *dsi)
 {
 	struct panel_info *pinfo = mipi_dsi_get_drvdata(dsi);
 	int err;
@@ -937,8 +937,6 @@ static int panel_remove(struct mipi_dsi_device *dsi)
 		dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", err);
 
 	drm_panel_remove(&pinfo->base);
-
-	return 0;
 }
 
 static void panel_shutdown(struct mipi_dsi_device *dsi)
diff --git a/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c b/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c
index 07f722f33fc5..857a2f0420d7 100644
--- a/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c
+++ b/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c
@@ -1622,7 +1622,7 @@ static void boe_panel_shutdown(struct mipi_dsi_device *dsi)
 	drm_panel_unprepare(&boe->base);
 }
 
-static int boe_panel_remove(struct mipi_dsi_device *dsi)
+static void boe_panel_remove(struct mipi_dsi_device *dsi)
 {
 	struct boe_panel *boe = mipi_dsi_get_drvdata(dsi);
 	int ret;
@@ -1635,8 +1635,6 @@ static int boe_panel_remove(struct mipi_dsi_device *dsi)
 
 	if (boe->base.dev)
 		drm_panel_remove(&boe->base);
-
-	return 0;
 }
 
 static const struct of_device_id boe_of_match[] = {
diff --git a/drivers/gpu/drm/panel/panel-dsi-cm.c b/drivers/gpu/drm/panel/panel-dsi-cm.c
index b0213a518f9d..ba17bcc4461c 100644
--- a/drivers/gpu/drm/panel/panel-dsi-cm.c
+++ b/drivers/gpu/drm/panel/panel-dsi-cm.c
@@ -579,7 +579,7 @@ err_bl:
 	return r;
 }
 
-static int dsicm_remove(struct mipi_dsi_device *dsi)
+static void dsicm_remove(struct mipi_dsi_device *dsi)
 {
 	struct panel_drv_data *ddata = mipi_dsi_get_drvdata(dsi);
 
@@ -593,8 +593,6 @@ static int dsicm_remove(struct mipi_dsi_device *dsi)
 
 	if (ddata->extbldev)
 		put_device(&ddata->extbldev->dev);
-
-	return 0;
 }
 
 static const struct dsic_panel_data taal_data = {
diff --git a/drivers/gpu/drm/panel/panel-ebbg-ft8719.c b/drivers/gpu/drm/panel/panel-ebbg-ft8719.c
index 386f8321b930..e85d63a176d0 100644
--- a/drivers/gpu/drm/panel/panel-ebbg-ft8719.c
+++ b/drivers/gpu/drm/panel/panel-ebbg-ft8719.c
@@ -250,7 +250,7 @@ static int ebbg_ft8719_probe(struct mipi_dsi_device *dsi)
 	return 0;
 }
 
-static int ebbg_ft8719_remove(struct mipi_dsi_device *dsi)
+static void ebbg_ft8719_remove(struct mipi_dsi_device *dsi)
 {
 	struct ebbg_ft8719 *ctx = mipi_dsi_get_drvdata(dsi);
 	int ret;
@@ -260,8 +260,6 @@ static int ebbg_ft8719_remove(struct mipi_dsi_device *dsi)
 		dev_err(&dsi->dev, "Failed to detach from DSI host: %d\n", ret);
 
 	drm_panel_remove(&ctx->panel);
-
-	return 0;
 }
 
 static const struct of_device_id ebbg_ft8719_of_match[] = {
diff --git a/drivers/gpu/drm/panel/panel-elida-kd35t133.c b/drivers/gpu/drm/panel/panel-elida-kd35t133.c
index 01dd555a7f26..eee714cf3f49 100644
--- a/drivers/gpu/drm/panel/panel-elida-kd35t133.c
+++ b/drivers/gpu/drm/panel/panel-elida-kd35t133.c
@@ -321,7 +321,7 @@ static void kd35t133_shutdown(struct mipi_dsi_device *dsi)
 		dev_err(&dsi->dev, "Failed to disable panel: %d\n", ret);
 }
 
-static int kd35t133_remove(struct mipi_dsi_device *dsi)
+static void kd35t133_remove(struct mipi_dsi_device *dsi)
 {
 	struct kd35t133 *ctx = mipi_dsi_get_drvdata(dsi);
 	int ret;
@@ -333,8 +333,6 @@ static int kd35t133_remove(struct mipi_dsi_device *dsi)
 		dev_err(&dsi->dev, "Failed to detach from DSI host: %d\n", ret);
 
 	drm_panel_remove(&ctx->panel);
-
-	return 0;
 }
 
 static const struct of_device_id kd35t133_of_match[] = {
diff --git a/drivers/gpu/drm/panel/panel-feixin-k101-im2ba02.c b/drivers/gpu/drm/panel/panel-feixin-k101-im2ba02.c
index cb0bb3076099..76572c922983 100644
--- a/drivers/gpu/drm/panel/panel-feixin-k101-im2ba02.c
+++ b/drivers/gpu/drm/panel/panel-feixin-k101-im2ba02.c
@@ -486,14 +486,12 @@ static int k101_im2ba02_dsi_probe(struct mipi_dsi_device *dsi)
 	return 0;
 }
 
-static int k101_im2ba02_dsi_remove(struct mipi_dsi_device *dsi)
+static void k101_im2ba02_dsi_remove(struct mipi_dsi_device *dsi)
 {
 	struct k101_im2ba02 *ctx = mipi_dsi_get_drvdata(dsi);
 
 	mipi_dsi_detach(dsi);
 	drm_panel_remove(&ctx->panel);
-
-	return 0;
 }
 
 static const struct of_device_id k101_im2ba02_of_match[] = {
diff --git a/drivers/gpu/drm/panel/panel-feiyang-fy07024di26a30d.c b/drivers/gpu/drm/panel/panel-feiyang-fy07024di26a30d.c
index ee61d60eceae..df493da50afe 100644
--- a/drivers/gpu/drm/panel/panel-feiyang-fy07024di26a30d.c
+++ b/drivers/gpu/drm/panel/panel-feiyang-fy07024di26a30d.c
@@ -233,14 +233,12 @@ static int feiyang_dsi_probe(struct mipi_dsi_device *dsi)
 	return 0;
 }
 
-static int feiyang_dsi_remove(struct mipi_dsi_device *dsi)
+static void feiyang_dsi_remove(struct mipi_dsi_device *dsi)
 {
 	struct feiyang *ctx = mipi_dsi_get_drvdata(dsi);
 
 	mipi_dsi_detach(dsi);
 	drm_panel_remove(&ctx->panel);
-
-	return 0;
 }
 
 static const struct of_device_id feiyang_of_match[] = {
diff --git a/drivers/gpu/drm/panel/panel-ilitek-ili9881c.c b/drivers/gpu/drm/panel/panel-ilitek-ili9881c.c
index 596861269774..cbb68caa36f2 100644
--- a/drivers/gpu/drm/panel/panel-ilitek-ili9881c.c
+++ b/drivers/gpu/drm/panel/panel-ilitek-ili9881c.c
@@ -923,14 +923,12 @@ static int ili9881c_dsi_probe(struct mipi_dsi_device *dsi)
 	return mipi_dsi_attach(dsi);
 }
 
-static int ili9881c_dsi_remove(struct mipi_dsi_device *dsi)
+static void ili9881c_dsi_remove(struct mipi_dsi_device *dsi)
 {
 	struct ili9881c *ctx = mipi_dsi_get_drvdata(dsi);
 
 	mipi_dsi_detach(dsi);
 	drm_panel_remove(&ctx->panel);
-
-	return 0;
 }
 
 static const struct ili9881c_desc lhr050h41_desc = {
diff --git a/drivers/gpu/drm/panel/panel-innolux-p079zca.c b/drivers/gpu/drm/panel/panel-innolux-p079zca.c
index f194b62e290c..9992d0d4c0e5 100644
--- a/drivers/gpu/drm/panel/panel-innolux-p079zca.c
+++ b/drivers/gpu/drm/panel/panel-innolux-p079zca.c
@@ -506,7 +506,7 @@ static int innolux_panel_probe(struct mipi_dsi_device *dsi)
 	return 0;
 }
 
-static int innolux_panel_remove(struct mipi_dsi_device *dsi)
+static void innolux_panel_remove(struct mipi_dsi_device *dsi)
 {
 	struct innolux_panel *innolux = mipi_dsi_get_drvdata(dsi);
 	int err;
@@ -524,8 +524,6 @@ static int innolux_panel_remove(struct mipi_dsi_device *dsi)
 		dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", err);
 
 	innolux_panel_del(innolux);
-
-	return 0;
 }
 
 static void innolux_panel_shutdown(struct mipi_dsi_device *dsi)
diff --git a/drivers/gpu/drm/panel/panel-jdi-fhd-r63452.c b/drivers/gpu/drm/panel/panel-jdi-fhd-r63452.c
index 31eafbc38ec0..d8765b2294fb 100644
--- a/drivers/gpu/drm/panel/panel-jdi-fhd-r63452.c
+++ b/drivers/gpu/drm/panel/panel-jdi-fhd-r63452.c
@@ -288,7 +288,7 @@ static int jdi_fhd_r63452_probe(struct mipi_dsi_device *dsi)
 	return 0;
 }
 
-static int jdi_fhd_r63452_remove(struct mipi_dsi_device *dsi)
+static void jdi_fhd_r63452_remove(struct mipi_dsi_device *dsi)
 {
 	struct jdi_fhd_r63452 *ctx = mipi_dsi_get_drvdata(dsi);
 	int ret;
@@ -298,8 +298,6 @@ static int jdi_fhd_r63452_remove(struct mipi_dsi_device *dsi)
 		dev_err(&dsi->dev, "Failed to detach from DSI host: %d\n", ret);
 
 	drm_panel_remove(&ctx->panel);
-
-	return 0;
 }
 
 static const struct of_device_id jdi_fhd_r63452_of_match[] = {
diff --git a/drivers/gpu/drm/panel/panel-jdi-lt070me05000.c b/drivers/gpu/drm/panel/panel-jdi-lt070me05000.c
index 3c86ad262d5e..8f4f137a2af6 100644
--- a/drivers/gpu/drm/panel/panel-jdi-lt070me05000.c
+++ b/drivers/gpu/drm/panel/panel-jdi-lt070me05000.c
@@ -482,7 +482,7 @@ static int jdi_panel_probe(struct mipi_dsi_device *dsi)
 	return 0;
 }
 
-static int jdi_panel_remove(struct mipi_dsi_device *dsi)
+static void jdi_panel_remove(struct mipi_dsi_device *dsi)
 {
 	struct jdi_panel *jdi = mipi_dsi_get_drvdata(dsi);
 	int ret;
@@ -497,8 +497,6 @@ static int jdi_panel_remove(struct mipi_dsi_device *dsi)
 			ret);
 
 	jdi_panel_del(jdi);
-
-	return 0;
 }
 
 static void jdi_panel_shutdown(struct mipi_dsi_device *dsi)
diff --git a/drivers/gpu/drm/panel/panel-khadas-ts050.c b/drivers/gpu/drm/panel/panel-khadas-ts050.c
index a3ec4cbdbf7a..1ab1ebe30882 100644
--- a/drivers/gpu/drm/panel/panel-khadas-ts050.c
+++ b/drivers/gpu/drm/panel/panel-khadas-ts050.c
@@ -830,7 +830,7 @@ static int khadas_ts050_panel_probe(struct mipi_dsi_device *dsi)
 	return err;
 }
 
-static int khadas_ts050_panel_remove(struct mipi_dsi_device *dsi)
+static void khadas_ts050_panel_remove(struct mipi_dsi_device *dsi)
 {
 	struct khadas_ts050_panel *khadas_ts050 = mipi_dsi_get_drvdata(dsi);
 	int err;
@@ -842,8 +842,6 @@ static int khadas_ts050_panel_remove(struct mipi_dsi_device *dsi)
 	drm_panel_remove(&khadas_ts050->base);
 	drm_panel_disable(&khadas_ts050->base);
 	drm_panel_unprepare(&khadas_ts050->base);
-
-	return 0;
 }
 
 static void khadas_ts050_panel_shutdown(struct mipi_dsi_device *dsi)
diff --git a/drivers/gpu/drm/panel/panel-kingdisplay-kd097d04.c b/drivers/gpu/drm/panel/panel-kingdisplay-kd097d04.c
index daccb1fd5fda..17f8d80cf2b3 100644
--- a/drivers/gpu/drm/panel/panel-kingdisplay-kd097d04.c
+++ b/drivers/gpu/drm/panel/panel-kingdisplay-kd097d04.c
@@ -415,7 +415,7 @@ static int kingdisplay_panel_probe(struct mipi_dsi_device *dsi)
 	return 0;
 }
 
-static int kingdisplay_panel_remove(struct mipi_dsi_device *dsi)
+static void kingdisplay_panel_remove(struct mipi_dsi_device *dsi)
 {
 	struct kingdisplay_panel *kingdisplay = mipi_dsi_get_drvdata(dsi);
 	int err;
@@ -433,8 +433,6 @@ static int kingdisplay_panel_remove(struct mipi_dsi_device *dsi)
 		dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", err);
 
 	kingdisplay_panel_del(kingdisplay);
-
-	return 0;
 }
 
 static void kingdisplay_panel_shutdown(struct mipi_dsi_device *dsi)
diff --git a/drivers/gpu/drm/panel/panel-leadtek-ltk050h3146w.c b/drivers/gpu/drm/panel/panel-leadtek-ltk050h3146w.c
index a5a414920430..5619f186d28c 100644
--- a/drivers/gpu/drm/panel/panel-leadtek-ltk050h3146w.c
+++ b/drivers/gpu/drm/panel/panel-leadtek-ltk050h3146w.c
@@ -628,7 +628,7 @@ static void ltk050h3146w_shutdown(struct mipi_dsi_device *dsi)
 		dev_err(&dsi->dev, "Failed to disable panel: %d\n", ret);
 }
 
-static int ltk050h3146w_remove(struct mipi_dsi_device *dsi)
+static void ltk050h3146w_remove(struct mipi_dsi_device *dsi)
 {
 	struct ltk050h3146w *ctx = mipi_dsi_get_drvdata(dsi);
 	int ret;
@@ -640,8 +640,6 @@ static int ltk050h3146w_remove(struct mipi_dsi_device *dsi)
 		dev_err(&dsi->dev, "Failed to detach from DSI host: %d\n", ret);
 
 	drm_panel_remove(&ctx->panel);
-
-	return 0;
 }
 
 static const struct of_device_id ltk050h3146w_of_match[] = {
diff --git a/drivers/gpu/drm/panel/panel-leadtek-ltk500hd1829.c b/drivers/gpu/drm/panel/panel-leadtek-ltk500hd1829.c
index 21e48923836d..39e408c9f762 100644
--- a/drivers/gpu/drm/panel/panel-leadtek-ltk500hd1829.c
+++ b/drivers/gpu/drm/panel/panel-leadtek-ltk500hd1829.c
@@ -477,7 +477,7 @@ static void ltk500hd1829_shutdown(struct mipi_dsi_device *dsi)
 		dev_err(&dsi->dev, "Failed to disable panel: %d\n", ret);
 }
 
-static int ltk500hd1829_remove(struct mipi_dsi_device *dsi)
+static void ltk500hd1829_remove(struct mipi_dsi_device *dsi)
 {
 	struct ltk500hd1829 *ctx = mipi_dsi_get_drvdata(dsi);
 	int ret;
@@ -489,8 +489,6 @@ static int ltk500hd1829_remove(struct mipi_dsi_device *dsi)
 		dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", ret);
 
 	drm_panel_remove(&ctx->panel);
-
-	return 0;
 }
 
 static const struct of_device_id ltk500hd1829_of_match[] = {
diff --git a/drivers/gpu/drm/panel/panel-mantix-mlaf057we51.c b/drivers/gpu/drm/panel/panel-mantix-mlaf057we51.c
index 31daae1da9c9..772e3b6acece 100644
--- a/drivers/gpu/drm/panel/panel-mantix-mlaf057we51.c
+++ b/drivers/gpu/drm/panel/panel-mantix-mlaf057we51.c
@@ -336,7 +336,7 @@ static void mantix_shutdown(struct mipi_dsi_device *dsi)
 	drm_panel_disable(&ctx->panel);
 }
 
-static int mantix_remove(struct mipi_dsi_device *dsi)
+static void mantix_remove(struct mipi_dsi_device *dsi)
 {
 	struct mantix *ctx = mipi_dsi_get_drvdata(dsi);
 
@@ -344,8 +344,6 @@ static int mantix_remove(struct mipi_dsi_device *dsi)
 
 	mipi_dsi_detach(dsi);
 	drm_panel_remove(&ctx->panel);
-
-	return 0;
 }
 
 static const struct of_device_id mantix_of_match[] = {
diff --git a/drivers/gpu/drm/panel/panel-novatek-nt35510.c b/drivers/gpu/drm/panel/panel-novatek-nt35510.c
index 1b3e0154bfb8..c613ad967ba6 100644
--- a/drivers/gpu/drm/panel/panel-novatek-nt35510.c
+++ b/drivers/gpu/drm/panel/panel-novatek-nt35510.c
@@ -966,7 +966,7 @@ static int nt35510_probe(struct mipi_dsi_device *dsi)
 	return 0;
 }
 
-static int nt35510_remove(struct mipi_dsi_device *dsi)
+static void nt35510_remove(struct mipi_dsi_device *dsi)
 {
 	struct nt35510 *nt = mipi_dsi_get_drvdata(dsi);
 	int ret;
@@ -978,8 +978,6 @@ static int nt35510_remove(struct mipi_dsi_device *dsi)
 		dev_err(&dsi->dev, "Failed to power off\n");
 
 	drm_panel_remove(&nt->panel);
-
-	return 0;
 }
 
 /*
diff --git a/drivers/gpu/drm/panel/panel-novatek-nt35560.c b/drivers/gpu/drm/panel/panel-novatek-nt35560.c
index 1b6042321ea1..cc7f96d70826 100644
--- a/drivers/gpu/drm/panel/panel-novatek-nt35560.c
+++ b/drivers/gpu/drm/panel/panel-novatek-nt35560.c
@@ -523,14 +523,12 @@ static int nt35560_probe(struct mipi_dsi_device *dsi)
 	return 0;
 }
 
-static int nt35560_remove(struct mipi_dsi_device *dsi)
+static void nt35560_remove(struct mipi_dsi_device *dsi)
 {
 	struct nt35560 *nt = mipi_dsi_get_drvdata(dsi);
 
 	mipi_dsi_detach(dsi);
 	drm_panel_remove(&nt->panel);
-
-	return 0;
 }
 
 static const struct of_device_id nt35560_of_match[] = {
diff --git a/drivers/gpu/drm/panel/panel-novatek-nt35950.c b/drivers/gpu/drm/panel/panel-novatek-nt35950.c
index 288c7fa83ecc..3a844917da07 100644
--- a/drivers/gpu/drm/panel/panel-novatek-nt35950.c
+++ b/drivers/gpu/drm/panel/panel-novatek-nt35950.c
@@ -620,7 +620,7 @@ static int nt35950_probe(struct mipi_dsi_device *dsi)
 	return 0;
 }
 
-static int nt35950_remove(struct mipi_dsi_device *dsi)
+static void nt35950_remove(struct mipi_dsi_device *dsi)
 {
 	struct nt35950 *nt