[PATCH v1 16/16] drm/panel: simple: use drm_panel infrastructure

[Sam Ravnborg <sam@xxxxxxxxxxxx>]

Use drm_panel infrastrucute:
- drm_panel has guards for calling disable/enable twice
- drm_panel has backlight support

To use the drm_panel infrastructure use the drm_panel_*
variants for prepare/enable/disable/unprepare.

Signed-off-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
Cc: Thierry Reding <thierry.reding@xxxxxxxxx>
Cc: Sam Ravnborg <sam@xxxxxxxxxxxx>
---
 drivers/gpu/drm/panel/panel-simple.c | 73 +++++-----------------------
 1 file changed, 11 insertions(+), 62 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
index bff7578f84dd..c7eed34f2c9c 100644
--- a/drivers/gpu/drm/panel/panel-simple.c
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -21,7 +21,6 @@
  * DEALINGS IN THE SOFTWARE.
  */
 
-#include <linux/backlight.h>
 #include <linux/delay.h>
 #include <linux/gpio/consumer.h>
 #include <linux/module.h>
@@ -98,13 +97,10 @@ struct panel_desc {
 
 struct panel_simple {
 	struct drm_panel base;
-	bool prepared;
-	bool enabled;
 	bool no_hpd;
 
 	const struct panel_desc *desc;
 
-	struct backlight_device *backlight;
 	struct regulator *supply;
 	struct i2c_adapter *ddc;
 
@@ -232,20 +228,9 @@ static int panel_simple_disable(struct drm_panel *panel)
 {
 	struct panel_simple *p = to_panel_simple(panel);
 
-	if (!p->enabled)
-		return 0;
-
-	if (p->backlight) {
-		p->backlight->props.power = FB_BLANK_POWERDOWN;
-		p->backlight->props.state |= BL_CORE_FBBLANK;
-		backlight_update_status(p->backlight);
-	}
-
 	if (p->desc->delay.disable)
 		msleep(p->desc->delay.disable);
 
-	p->enabled = false;
-
 	return 0;
 }
 
@@ -253,9 +238,6 @@ static int panel_simple_unprepare(struct drm_panel *panel)
 {
 	struct panel_simple *p = to_panel_simple(panel);
 
-	if (!p->prepared)
-		return 0;
-
 	gpiod_set_value_cansleep(p->enable_gpio, 0);
 
 	regulator_disable(p->supply);
@@ -263,8 +245,6 @@ static int panel_simple_unprepare(struct drm_panel *panel)
 	if (p->desc->delay.unprepare)
 		msleep(p->desc->delay.unprepare);
 
-	p->prepared = false;
-
 	return 0;
 }
 
@@ -274,9 +254,6 @@ static int panel_simple_prepare(struct drm_panel *panel)
 	unsigned int delay;
 	int err;
 
-	if (p->prepared)
-		return 0;
-
 	err = regulator_enable(p->supply);
 	if (err < 0) {
 		dev_err(panel->dev, "failed to enable supply: %d\n", err);
@@ -291,8 +268,6 @@ static int panel_simple_prepare(struct drm_panel *panel)
 	if (delay)
 		msleep(delay);
 
-	p->prepared = true;
-
 	return 0;
 }
 
@@ -300,20 +275,9 @@ static int panel_simple_enable(struct drm_panel *panel)
 {
 	struct panel_simple *p = to_panel_simple(panel);
 
-	if (p->enabled)
-		return 0;
-
 	if (p->desc->delay.enable)
 		msleep(p->desc->delay.enable);
 
-	if (p->backlight) {
-		p->backlight->props.state &= ~BL_CORE_FBBLANK;
-		p->backlight->props.power = FB_BLANK_UNBLANK;
-		backlight_update_status(p->backlight);
-	}
-
-	p->enabled = true;
-
 	return 0;
 }
 
@@ -413,7 +377,7 @@ static void panel_simple_parse_panel_timing_node(struct device *dev,
 
 static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
 {
-	struct device_node *backlight, *ddc;
+	struct device_node *ddc;
 	struct panel_simple *panel;
 	struct display_timing dt;
 	int err;
@@ -422,8 +386,6 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
 	if (!panel)
 		return -ENOMEM;
 
-	panel->enabled = false;
-	panel->prepared = false;
 	panel->desc = desc;
 
 	panel->no_hpd = of_property_read_bool(dev->of_node, "no-hpd");
@@ -441,24 +403,13 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
 		return err;
 	}
 
-	backlight = of_parse_phandle(dev->of_node, "backlight", 0);
-	if (backlight) {
-		panel->backlight = of_find_backlight_by_node(backlight);
-		of_node_put(backlight);
-
-		if (!panel->backlight)
-			return -EPROBE_DEFER;
-	}
-
 	ddc = of_parse_phandle(dev->of_node, "ddc-i2c-bus", 0);
 	if (ddc) {
 		panel->ddc = of_find_i2c_adapter_by_node(ddc);
 		of_node_put(ddc);
 
-		if (!panel->ddc) {
-			err = -EPROBE_DEFER;
-			goto free_backlight;
-		}
+		if (!panel->ddc)
+			return -EPROBE_DEFER;
 	}
 
 	if (!of_get_display_timing(dev->of_node, "panel-timing", &dt))
@@ -468,6 +419,10 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
 	panel->base.dev = dev;
 	panel->base.funcs = &panel_simple_funcs;
 
+	err = drm_panel_of_backlight(&panel->base);
+	if (err)
+		goto free_ddc;
+
 	err = drm_panel_add(&panel->base);
 	if (err < 0)
 		goto free_ddc;
@@ -479,9 +434,6 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
 free_ddc:
 	if (panel->ddc)
 		put_device(&panel->ddc->dev);
-free_backlight:
-	if (panel->backlight)
-		put_device(&panel->backlight->dev);
 
 	return err;
 }
@@ -492,15 +444,12 @@ static int panel_simple_remove(struct device *dev)
 
 	drm_panel_remove(&panel->base);
 
-	panel_simple_disable(&panel->base);
-	panel_simple_unprepare(&panel->base);
+	drm_panel_disable(&panel->base);
+	drm_panel_unprepare(&panel->base);
 
 	if (panel->ddc)
 		put_device(&panel->ddc->dev);
 
-	if (panel->backlight)
-		put_device(&panel->backlight->dev);
-
 	return 0;
 }
 
@@ -508,8 +457,8 @@ static void panel_simple_shutdown(struct device *dev)
 {
 	struct panel_simple *panel = dev_get_drvdata(dev);
 
-	panel_simple_disable(&panel->base);
-	panel_simple_unprepare(&panel->base);
+	drm_panel_disable(&panel->base);
+	drm_panel_unprepare(&panel->base);
 }
 
 static const struct drm_display_mode ampire_am_480272h3tmqw_t01h_mode = {
-- 
2.20.1