This patch adds a simple driver to handle all the LCD and LED powerup/down routines needed to support eDP/LVDS panels. The LCD and LED units are usually powered up via regulators, and almost on all boards, we will have a BACKLIGHT_EN pin to enable/ disable the backlight. Sometimes, we can have LCD_EN switches as well. The routines in this driver can be used to control panel power sequence on such boards. Signed-off-by: Ajay Kumar <ajaykumar.rs@xxxxxxxxxxx> Signed-off-by: Rahul Sharma <Rahul.Sharma@xxxxxxxxxxx> --- drivers/gpu/drm/panel/Kconfig | 10 ++ drivers/gpu/drm/panel/Makefile | 1 + drivers/gpu/drm/panel/panel-lvds.c | 268 ++++++++++++++++++++++++++++++++++++ 3 files changed, 279 insertions(+) create mode 100644 drivers/gpu/drm/panel/panel-lvds.c diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig index 4ec874d..8fe7ee5 100644 --- a/drivers/gpu/drm/panel/Kconfig +++ b/drivers/gpu/drm/panel/Kconfig @@ -30,4 +30,14 @@ config DRM_PANEL_S6E8AA0 select DRM_MIPI_DSI select VIDEOMODE_HELPERS +config DRM_PANEL_EDP_LVDS + tristate "support for eDP/LVDS panels" + depends on OF && DRM_PANEL + select VIDEOMODE_HELPERS + help + DRM panel driver for direct eDP panels or LVDS connected + via DP bridges, that need at most a regulator for LCD unit, + a regulator for LED unit and/or enable GPIOs for LCD or LED units. + Delay values can also be specified to support powerup and + powerdown process. endmenu diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile index 8b92921..eaafa01 100644 --- a/drivers/gpu/drm/panel/Makefile +++ b/drivers/gpu/drm/panel/Makefile @@ -1,3 +1,4 @@ obj-$(CONFIG_DRM_PANEL_SIMPLE) += panel-simple.o obj-$(CONFIG_DRM_PANEL_LD9040) += panel-ld9040.o obj-$(CONFIG_DRM_PANEL_S6E8AA0) += panel-s6e8aa0.o +obj-$(CONFIG_DRM_PANEL_EDP_LVDS) += panel-lvds.o diff --git a/drivers/gpu/drm/panel/panel-lvds.c b/drivers/gpu/drm/panel/panel-lvds.c new file mode 100644 index 0000000..ce20587 --- /dev/null +++ b/drivers/gpu/drm/panel/panel-lvds.c @@ -0,0 +1,268 @@ +/* + * panel driver for lvds and eDP panels + * + * Copyright (c) 2014 Samsung Electronics Co., Ltd + * + * Ajay Kumar <ajaykumar.rs@xxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/gpio/consumer.h> +#include <linux/module.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/regulator/consumer.h> + +#include <video/of_videomode.h> +#include <video/videomode.h> + +#include <drm/drmP.h> +#include <drm/drm_crtc.h> +#include <drm/drm_panel.h> + +struct panel_lvds { + struct drm_panel base; + struct regulator *backlight_fet; + struct regulator *lcd_fet; + struct gpio_desc *lcd_en_gpio; + struct gpio_desc *led_en_gpio; + struct videomode vm; + int width_mm; + int height_mm; + bool backlight_fet_enabled; + bool lcd_fet_enabled; + int panel_prepare_delay; + int panel_enable_delay; + int panel_disable_delay; + int panel_unprepare_delay; +}; + +static inline struct panel_lvds *to_panel(struct drm_panel *panel) +{ + return container_of(panel, struct panel_lvds, base); +} + +static int panel_lvds_prepare(struct drm_panel *panel) +{ + struct panel_lvds *lvds_panel = to_panel(panel); + + if (!lvds_panel->lcd_fet_enabled) { + if (regulator_enable(lvds_panel->lcd_fet)) { + DRM_ERROR("failed to enable LCD fet\n"); + return -EAGAIN; + } + lvds_panel->lcd_fet_enabled = true; + } + + if (lvds_panel->lcd_en_gpio) + gpiod_set_value(lvds_panel->lcd_en_gpio, 1); + + msleep(lvds_panel->panel_prepare_delay); + + return 0; +} + +static int panel_lvds_enable(struct drm_panel *panel) +{ + struct panel_lvds *lvds_panel = to_panel(panel); + + if (!lvds_panel->backlight_fet_enabled) { + if (regulator_enable(lvds_panel->backlight_fet)) { + DRM_ERROR("failed to enable LED fet\n"); + return -EAGAIN; + } + lvds_panel->backlight_fet_enabled = true; + } + + msleep(lvds_panel->panel_enable_delay); + + if (lvds_panel->led_en_gpio) + gpiod_set_value(lvds_panel->led_en_gpio, 1); + + return 0; +} + +static int panel_lvds_disable(struct drm_panel *panel) +{ + struct panel_lvds *lvds_panel = to_panel(panel); + + if (lvds_panel->led_en_gpio) + gpiod_set_value(lvds_panel->led_en_gpio, 0); + + if (lvds_panel->backlight_fet_enabled) { + regulator_disable(lvds_panel->backlight_fet); + lvds_panel->backlight_fet_enabled = false; + } + + msleep(lvds_panel->panel_disable_delay); + + return 0; +} + +static int panel_lvds_unprepare(struct drm_panel *panel) +{ + struct panel_lvds *lvds_panel = to_panel(panel); + + if (lvds_panel->lcd_en_gpio) + gpiod_set_value(lvds_panel->lcd_en_gpio, 0); + + if (lvds_panel->lcd_fet_enabled) { + regulator_disable(lvds_panel->lcd_fet); + lvds_panel->lcd_fet_enabled = false; + } + + msleep(lvds_panel->panel_unprepare_delay); + + return 0; +} + +static int panel_lvds_get_modes(struct drm_panel *panel) +{ + struct drm_connector *connector = panel->connector; + struct panel_lvds *lvds_panel = to_panel(panel); + struct drm_display_mode *mode; + + mode = drm_mode_create(connector->dev); + if (!mode) { + DRM_ERROR("failed to create a new display mode.\n"); + return 0; + } + + drm_display_mode_from_videomode(&lvds_panel->vm, mode); + mode->width_mm = lvds_panel->width_mm; + mode->height_mm = lvds_panel->height_mm; + connector->display_info.width_mm = mode->width_mm; + connector->display_info.height_mm = mode->height_mm; + + mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED; + drm_mode_set_name(mode); + drm_mode_probed_add(connector, mode); + + return 1; +} + +static const struct drm_panel_funcs panel_lvds_funcs = { + .unprepare = panel_lvds_unprepare, + .disable = panel_lvds_disable, + .prepare = panel_lvds_prepare, + .enable = panel_lvds_enable, + .get_modes = panel_lvds_get_modes, +}; + +static int panel_lvds_probe(struct platform_device *pdev) +{ + struct panel_lvds *panel; + struct device *dev = &pdev->dev; + struct device_node *node = dev->of_node; + int ret; + + panel = devm_kzalloc(dev, sizeof(*panel), GFP_KERNEL); + if (!panel) + return -ENOMEM; + + ret = of_get_videomode(node, &panel->vm, 0); + if (ret) { + DRM_ERROR("failed: of_get_videomode() : %d\n", ret); + return ret; + } + + panel->lcd_fet = devm_regulator_get(dev, "lcd"); + if (IS_ERR(panel->lcd_fet)) + return -EPROBE_DEFER; + + panel->backlight_fet = devm_regulator_get(dev, "backlight"); + if (IS_ERR(panel->backlight_fet)) + return -EPROBE_DEFER; + + of_property_read_u32(node, "panel-width-mm", &panel->width_mm); + of_property_read_u32(node, "panel-height-mm", &panel->height_mm); + + of_property_read_u32(node, "panel-prepare-delay", + &panel->panel_prepare_delay); + of_property_read_u32(node, "panel-enable-delay", + &panel->panel_enable_delay); + of_property_read_u32(node, "panel-disable-delay", + &panel->panel_disable_delay); + of_property_read_u32(node, "panel-unprepare-delay", + &panel->panel_unprepare_delay); + + panel->lcd_en_gpio = devm_gpiod_get(dev, "lcd-enable"); + if (IS_ERR(panel->lcd_en_gpio)) { + ret = PTR_ERR(panel->lcd_en_gpio); + if (ret != -ENOENT) { + dev_err(dev, "failed to request GPIO: %d\n", ret); + return ret; + } + panel->lcd_en_gpio = NULL; + } else { + ret = gpiod_direction_output(panel->lcd_en_gpio, 0); + if (ret < 0) { + dev_err(dev, "failed to setup GPIO: %d\n", ret); + return ret; + } + } + + panel->led_en_gpio = devm_gpiod_get(dev, "backlight-enable"); + if (IS_ERR(panel->led_en_gpio)) { + ret = PTR_ERR(panel->led_en_gpio); + if (ret != -ENOENT) { + dev_err(dev, "failed to request GPIO: %d\n", ret); + return ret; + } + panel->led_en_gpio = NULL; + } else { + ret = gpiod_direction_output(panel->led_en_gpio, 0); + if (ret < 0) { + dev_err(dev, "failed to setup GPIO: %d\n", ret); + return ret; + } + } + + drm_panel_init(&panel->base); + panel->base.dev = dev; + panel->base.funcs = &panel_lvds_funcs; + + ret = drm_panel_add(&panel->base); + if (ret < 0) + return ret; + + dev_set_drvdata(dev, panel); + + return 0; +} + +static int panel_lvds_remove(struct platform_device *pdev) +{ + struct panel_lvds *panel = dev_get_drvdata(&pdev->dev); + + panel_lvds_disable(&panel->base); + panel_lvds_unprepare(&panel->base); + + drm_panel_remove(&panel->base); + + return 0; +} + +static const struct of_device_id lvds_panel_dt_match[] = { + { .compatible = "panel-lvds" }, + {}, +}; +MODULE_DEVICE_TABLE(of, lvds_panel_dt_match); + +struct platform_driver lvds_panel_driver = { + .driver = { + .name = "panel_lvds", + .owner = THIS_MODULE, + .of_match_table = lvds_panel_dt_match, + }, + .probe = panel_lvds_probe, + .remove = panel_lvds_remove, +}; +module_platform_driver(lvds_panel_driver); + +MODULE_AUTHOR("Ajay Kumar <ajaykumar.rs@xxxxxxxxxxx>"); +MODULE_DESCRIPTION("lvds/eDP panel driver"); +MODULE_LICENSE("GPL v2"); -- 1.7.9.5 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel