In order to support the "enable GPIO" available in many panel devices, this commit adds a proper devicetree binding.
By providing an enable GPIO in the devicetree, the driver can now turn off and on the panel device, and/or the backlight device. Both the backlight and the GPIO are optional properties.
Tested-by: Darren Etheridge detheridge@ti.com Signed-off-by: Ezequiel Garcia ezequiel@vanguardiasur.com.ar --- .../devicetree/bindings/drm/tilcdc/panel.txt | 2 ++ drivers/gpu/drm/tilcdc/tilcdc_panel.c | 37 +++++++++++++++++++--- 2 files changed, 34 insertions(+), 5 deletions(-)
diff --git a/Documentation/devicetree/bindings/drm/tilcdc/panel.txt b/Documentation/devicetree/bindings/drm/tilcdc/panel.txt index 10a06e8..4ab9e23 100644 --- a/Documentation/devicetree/bindings/drm/tilcdc/panel.txt +++ b/Documentation/devicetree/bindings/drm/tilcdc/panel.txt @@ -20,6 +20,7 @@ Required properties:
Optional properties: - backlight: phandle of the backlight device attached to the panel +- enable-gpios: GPIO pin to enable or disable the panel
Recommended properties: - pinctrl-names, pinctrl-0: the pincontrol settings to configure @@ -33,6 +34,7 @@ Example: pinctrl-names = "default"; pinctrl-0 = <&bone_lcd3_cape_lcd_pins>; backlight = <&backlight>; + enable-gpios = <&gpio3 19 0>;
panel-info { ac-bias = <255>; diff --git a/drivers/gpu/drm/tilcdc/tilcdc_panel.c b/drivers/gpu/drm/tilcdc/tilcdc_panel.c index f2a5b23..7a03158 100644 --- a/drivers/gpu/drm/tilcdc/tilcdc_panel.c +++ b/drivers/gpu/drm/tilcdc/tilcdc_panel.c @@ -18,6 +18,7 @@ #include <linux/pinctrl/pinmux.h> #include <linux/pinctrl/consumer.h> #include <linux/backlight.h> +#include <linux/gpio/consumer.h> #include <video/display_timing.h> #include <video/of_display_timing.h> #include <video/videomode.h> @@ -29,6 +30,7 @@ struct panel_module { struct tilcdc_panel_info *info; struct display_timings *timings; struct backlight_device *backlight; + struct gpio_desc *enable_gpio; }; #define to_panel_module(x) container_of(x, struct panel_module, base)
@@ -55,13 +57,17 @@ static void panel_encoder_dpms(struct drm_encoder *encoder, int mode) { struct panel_encoder *panel_encoder = to_panel_encoder(encoder); struct backlight_device *backlight = panel_encoder->mod->backlight; + struct gpio_desc *gpio = panel_encoder->mod->enable_gpio;
- if (!backlight) - return; + if (backlight) { + backlight->props.power = mode == DRM_MODE_DPMS_ON ? + FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN; + backlight_update_status(backlight); + }
- backlight->props.power = mode == DRM_MODE_DPMS_ON - ? FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN; - backlight_update_status(backlight); + if (gpio) + gpiod_set_value_cansleep(gpio, + mode == DRM_MODE_DPMS_ON ? 1 : 0); }
static bool panel_encoder_mode_fixup(struct drm_encoder *encoder, @@ -369,6 +375,25 @@ static int panel_probe(struct platform_device *pdev) dev_info(&pdev->dev, "found backlight\n"); }
+ panel_mod->enable_gpio = devm_gpiod_get(&pdev->dev, "enable"); + if (IS_ERR(panel_mod->enable_gpio)) { + ret = PTR_ERR(panel_mod->enable_gpio); + if (ret != -ENOENT) { + dev_err(&pdev->dev, "failed to request enable GPIO\n"); + goto fail_backlight; + } + + /* Optional GPIO is not here, continue silently. */ + panel_mod->enable_gpio = NULL; + } else { + ret = gpiod_direction_output(panel_mod->enable_gpio, 0); + if (ret < 0) { + dev_err(&pdev->dev, "failed to setup GPIO\n"); + goto fail_backlight; + } + dev_info(&pdev->dev, "found enable GPIO\n"); + } + mod = &panel_mod->base; pdev->dev.platform_data = mod;
@@ -401,6 +426,8 @@ fail_timings:
fail_free: tilcdc_module_cleanup(mod); + +fail_backlight: if (panel_mod->backlight) put_device(&panel_mod->backlight->dev); return ret;