[PATCH v2 02/18] drm/panel: lvds: Add support for the power-supply property

Maxime Ripard
2017-11-27T15:41:26Z

A significant number of panels need to power up a regulator in order to
operate properly. Add support for the power-supply property to enable and
disable such a regulator whenever needed.

Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
---
drivers/gpu/drm/panel/panel-lvds.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)

diff --git a/drivers/gpu/drm/panel/panel-lvds.c b/drivers/gpu/drm/panel/panel-lvds.c
index e2d57c01200b..57e38a9e7ab4 100644
--- a/drivers/gpu/drm/panel/panel-lvds.c
+++ b/drivers/gpu/drm/panel/panel-lvds.c
@@ -17,6 +17,7 @@
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
#include <linux/slab.h>

#include <drm/drmP.h>
@@ -39,6 +40,7 @@ struct panel_lvds {
bool data_mirror;

struct backlight_device *backlight;
+ struct regulator *supply;

struct gpio_desc *enable_gpio;
struct gpio_desc *reset_gpio;
@@ -69,6 +71,9 @@ static int panel_lvds_unprepare(struct drm_panel *panel)
if (lvds->enable_gpio)
gpiod_set_value_cansleep(lvds->enable_gpio, 0);

+ if (lvds->supply)
+ regulator_disable(lvds->supply);
+
return 0;
}

@@ -76,6 +81,17 @@ static int panel_lvds_prepare(struct drm_panel *panel)
{
struct panel_lvds *lvds = to_panel_lvds(panel);

+ if (lvds->supply) {
+ int err;
+
+ err = regulator_enable(lvds->supply);
+ if (err < 0) {
+ dev_err(lvds->dev, "failed to enable supply: %d\n",
+ err);
+ return err;
+ }
+ }
+
if (lvds->enable_gpio)
gpiod_set_value_cansleep(lvds->enable_gpio, 1);

@@ -196,6 +212,13 @@ static int panel_lvds_probe(struct platform_device *pdev)
if (ret < 0)
return ret;

+ lvds->supply = devm_regulator_get_optional(lvds->dev, "power");
+ if (IS_ERR(lvds->supply)) {
+ ret = PTR_ERR(lvds->supply);
+ dev_err(lvds->dev, "failed to request regulator: %d\n", ret);
+ return ret;
+ }
+
/* Get GPIOs and backlight controller. */
lvds->enable_gpio = devm_gpiod_get_optional(lvds->dev, "enable",
GPIOD_OUT_LOW);
--
git-series 0.9.1