[PATCH v2 2/4] drm: panel: s6d16d0: Move DSI commands to enable/disable

[Linus Walleij <linus.walleij@linaro.org>]

Due to semantic changes in the bridge core, panels cannot send
any DSI commands in the prepare/unprepare callbacks: there is
no guarantee that the DSI transmitter is available at this
point.

Cc: Aradhya Bhatia <a-bhatia1@ti.com>
Fixes: c9b1150a68d9 ("drm/atomic-helper: Re-order bridge chain pre-enable and post-disable")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
 drivers/gpu/drm/panel/panel-samsung-s6d16d0.c | 35 ++++++++++++---------------
 1 file changed, 16 insertions(+), 19 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-samsung-s6d16d0.c b/drivers/gpu/drm/panel/panel-samsung-s6d16d0.c
index ba1a02000bb9..0b343e627500 100644
--- a/drivers/gpu/drm/panel/panel-samsung-s6d16d0.c
+++ b/drivers/gpu/drm/panel/panel-samsung-s6d16d0.c
@@ -48,15 +48,6 @@ static inline struct s6d16d0 *panel_to_s6d16d0(struct drm_panel *panel)
 static int s6d16d0_unprepare(struct drm_panel *panel)
 {
 	struct s6d16d0 *s6 = panel_to_s6d16d0(panel);
-	struct mipi_dsi_device *dsi = to_mipi_dsi_device(s6->dev);
-	int ret;
-
-	/* Enter sleep mode */
-	ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
-	if (ret) {
-		dev_err(s6->dev, "failed to enter sleep mode (%d)\n", ret);
-		return ret;
-	}
 
 	/* Assert RESET */
 	gpiod_set_value_cansleep(s6->reset_gpio, 1);
@@ -68,7 +59,6 @@ static int s6d16d0_unprepare(struct drm_panel *panel)
 static int s6d16d0_prepare(struct drm_panel *panel)
 {
 	struct s6d16d0 *s6 = panel_to_s6d16d0(panel);
-	struct mipi_dsi_device *dsi = to_mipi_dsi_device(s6->dev);
 	int ret;
 
 	ret = regulator_enable(s6->supply);
@@ -84,6 +74,15 @@ static int s6d16d0_prepare(struct drm_panel *panel)
 	gpiod_set_value_cansleep(s6->reset_gpio, 0);
 	msleep(120);
 
+	return 0;
+}
+
+static int s6d16d0_enable(struct drm_panel *panel)
+{
+	struct s6d16d0 *s6 = panel_to_s6d16d0(panel);
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(s6->dev);
+	int ret;
+
 	/* Enabe tearing mode: send TE (tearing effect) at VBLANK */
 	ret = mipi_dsi_dcs_set_tear_on(dsi,
 				       MIPI_DSI_DCS_TEAR_MODE_VBLANK);
@@ -98,15 +97,6 @@ static int s6d16d0_prepare(struct drm_panel *panel)
 		return ret;
 	}
 
-	return 0;
-}
-
-static int s6d16d0_enable(struct drm_panel *panel)
-{
-	struct s6d16d0 *s6 = panel_to_s6d16d0(panel);
-	struct mipi_dsi_device *dsi = to_mipi_dsi_device(s6->dev);
-	int ret;
-
 	ret = mipi_dsi_dcs_set_display_on(dsi);
 	if (ret) {
 		dev_err(s6->dev, "failed to turn display on (%d)\n", ret);
@@ -128,6 +118,13 @@ static int s6d16d0_disable(struct drm_panel *panel)
 		return ret;
 	}
 
+	/* Enter sleep mode */
+	ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
+	if (ret) {
+		dev_err(s6->dev, "failed to enter sleep mode (%d)\n", ret);
+		return ret;
+	}
+
 	return 0;
 }
 

-- 
2.51.0