Please remove unnecessary under lines as below.On Wednesday, April 16, 2014 11:33 PM, Ajay Kumar wrote:
>
> This patch adds a simple driver to handle all the LCD and LED
> powerup/down routines needed to support eDP/eDP-LVDS panels
> supported on exynos boards.
>
> Most of the eDP/LVDS panels need this sequence for powerup:
> -- LCD unit powerup/LCD_EN
> -- video data on
> -- LED unit powerup/BL_EN
>
> The LCD and LED units are usually powered up via regulators,
> and almost on all boards, we will have a BL_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@samsung.com>
> ---
> .../devicetree/bindings/panel/exynos-dp-panel.txt | 32 ++++
> drivers/gpu/drm/panel/Kconfig | 9 +
> drivers/gpu/drm/panel/Makefile | 1 +
> drivers/gpu/drm/panel/panel-exynos-dp.c | 213 +++++++++++++++++++++
> 4 files changed, 255 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/panel/exynos-dp-panel.txt
> create mode 100644 drivers/gpu/drm/panel/panel-exynos-dp.c
>
> diff --git a/Documentation/devicetree/bindings/panel/exynos-dp-panel.txt
> b/Documentation/devicetree/bindings/panel/exynos-dp-panel.txt
> new file mode 100644
> index 0000000..a1428d2
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/panel/exynos-dp-panel.txt
> @@ -0,0 +1,32 @@
> +exynos_DP_panel/DP_to_LVDS_panel
Exynos DP panel/DP to LVDS panel
'bck' means 'backlight'? Then, just use 'backlight_fet'.
> +==================================
> +
> +Required properties:
> + - compatible: "samsung,exynos-dp-panel"
> +
> +Optional properties:
> + -samsung,lcd-en-gpio:
> + eDP panel LCD poweron GPIO.
> + Indicates which GPIO needs to be powered up as output
> + to powerup/enable the switch to the LCD panel.
> + -samsung,led-en-gpio:
> + eDP panel LED enable GPIO.
> + Indicates which GPIO needs to be powered up as output
> + to enable the backlight.
> + -samsung,power-up-delay:
> + eDP panel powerup delay value in ms.
> + Delay in ms needed for the eDP panel to properly
> + powerup after giving powerup signals to the panel.
> + -samsung,power-down-delay:
> + eDP panel powerdown delay value in ms.
> + Delay in ms needed for the eDP panel to properly
> + powerdown after giving powerdown signals to the panel.
> +
> +Example:
> +
> + dp-panel {
> + compatible = "samsung,exynos-dp-panel";
> + samsung,led-en-gpio = <&gpx3 0 1>;
> + samsung,power-up-delay = <40>;
> + samsung,power-down-delay = <50>;
> + };
> diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
> index 4ec874d..ea9d5ac 100644
> --- a/drivers/gpu/drm/panel/Kconfig
> +++ b/drivers/gpu/drm/panel/Kconfig
> @@ -30,4 +30,13 @@ config DRM_PANEL_S6E8AA0
> select DRM_MIPI_DSI
> select VIDEOMODE_HELPERS
>
> +config DRM_PANEL_EXYNOS_DP
> + tristate "support for DP panels"
> + depends on OF && DRM_PANEL && DRM_EXYNOS_DP
> + help
> + DRM panel driver for DP panels and 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..30311a4 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_EXYNOS_DP) += panel-exynos-dp.o
> diff --git a/drivers/gpu/drm/panel/panel-exynos-dp.c b/drivers/gpu/drm/panel/panel-exynos-dp.c
> new file mode 100644
> index 0000000..e85a7b2
> --- /dev/null
> +++ b/drivers/gpu/drm/panel/panel-exynos-dp.c
> @@ -0,0 +1,213 @@
> +/*
> + * Exynos DP panel driver
> + *
> + * Copyright (c) 2014 Samsung Electronics Co., Ltd
> + *
> + * Ajay Kumar <ajaykumar.rs@samsung.com>
> + *
> + * 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/component.h>
> +#include <linux/gpio.h>
> +#include <linux/module.h>
> +#include <linux/of_gpio.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +#include <linux/regulator/consumer.h>
> +
> +#include <drm/drmP.h>
> +#include <drm/drm_crtc.h>
> +#include <drm/drm_panel.h>
> +
> +struct panel_exynos_dp {
> + struct drm_panel base;
> + struct regulator *bck_fet;
> + struct regulator *lcd_fet;
Also, I cannot understand the meaning of 'fet'.
What's the meaning of the 'fet'?
panel_exynos_dp_pre_enable() always returns '0'.> + int led_en_gpio;
> + int lcd_en_gpio;
> + int power_up_delay;
> + int power_down_delay;
> + bool enabled;
> +};
> +
> +static inline struct panel_exynos_dp *to_panel(struct drm_panel *panel)
> +{
> + return container_of(panel, struct panel_exynos_dp, base);
> +}
> +
> +static int panel_exynos_dp_disable(struct drm_panel *panel)
> +{
> + struct panel_exynos_dp *dp_panel = to_panel(panel);
> + bool enable_delay = false;
> +
> + if (!dp_panel->enabled)
> + return 0;
> +
> + if (gpio_is_valid(dp_panel->led_en_gpio))
> + gpio_set_value(dp_panel->led_en_gpio, 0);
> +
> + if (!IS_ERR_OR_NULL(dp_panel->bck_fet))
> + regulator_disable(dp_panel->bck_fet);
> +
> + if (gpio_is_valid(dp_panel->lcd_en_gpio)) {
> + gpio_set_value(dp_panel->lcd_en_gpio, 0);
> + enable_delay = true;
> + }
> +
> + if (!IS_ERR_OR_NULL(dp_panel->lcd_fet)) {
> + regulator_disable(dp_panel->lcd_fet);
> + enable_delay = true;
> + }
> +
> + if (enable_delay)
> + msleep(dp_panel->power_down_delay);
> +
> + dp_panel->enabled = false;
> +
> + return 0;
> +}
> +
> +static int panel_exynos_dp_pre_enable(struct drm_panel *panel)
These are two ways. Either one will be better.
1. Make return values meaningful. In other words, add the case
returning error values.
2. Change the return type to 'void'
> +{
> + struct panel_exynos_dp *dp_panel = to_panel(panel);
> + bool enable_delay = false;
> +
> + if (dp_panel->enabled)
> + return 0;
> +
> + if (!IS_ERR_OR_NULL(dp_panel->lcd_fet)) {
> + if (regulator_enable(dp_panel->lcd_fet))
> + DRM_ERROR("Failed to enable LCD fet\n");
> + enable_delay = true;
> + }
> +
> + if (gpio_is_valid(dp_panel->lcd_en_gpio)) {
> + gpio_set_value(dp_panel->lcd_en_gpio, 1);
> + enable_delay = true;
> + }
> +
> + if (enable_delay)
> + msleep(dp_panel->power_up_delay);
> +
> + return 0;
> +}
> +
> +static int panel_exynos_dp_enable(struct drm_panel *panel)
> +{
> + struct panel_exynos_dp *dp_panel = to_panel(panel);
> +
> + if (dp_panel->enabled)
> + return 0;
> +
> + if (!IS_ERR_OR_NULL(dp_panel->bck_fet))
> + if (regulator_enable(dp_panel->bck_fet))
> + DRM_ERROR("Failed to enable LED fet\n");
> +
> + if (gpio_is_valid(dp_panel->led_en_gpio))
> + gpio_set_value(dp_panel->led_en_gpio, 1);
> +
> + dp_panel->enabled = true;
> +
> + return 0;
> +}
> +
> +static const struct drm_panel_funcs panel_exynos_dp_funcs = {
> + .disable = panel_exynos_dp_disable,
> + .pre_enable = panel_exynos_dp_pre_enable,
> + .enable = panel_exynos_dp_enable,
> +};
> +
> +static int panel_exynos_dp_probe(struct platform_device *pdev)
> +{
> + struct panel_exynos_dp *dp_panel;
> + struct device *dev = &pdev->dev;
> + int ret;
> +
> + dp_panel = devm_kzalloc(dev, sizeof(*dp_panel), GFP_KERNEL);
> + if (!dp_panel)
> + return -ENOMEM;
> +
> + dp_panel->enabled = false;
> +
> + dp_panel->lcd_en_gpio = of_get_named_gpio(dev->of_node,
> + "samsung,lcd-en-gpio", 0);
> + dp_panel->led_en_gpio = of_get_named_gpio(dev->of_node,
> + "samsung,led-en-gpio", 0);
> +
> + of_property_read_u32(dev->of_node, "samsung,power-up-delay",
> + &dp_panel->power_up_delay);
> + of_property_read_u32(dev->of_node, "samsung,power-down-delay",
> + &dp_panel->power_down_delay);
> +
> + dp_panel->lcd_fet = devm_regulator_get(dev, "lcd_vdd");
> + if (IS_ERR(dp_panel->lcd_fet))
> + return PTR_ERR(dp_panel->lcd_fet);
> +
> + dp_panel->bck_fet = devm_regulator_get(dev, "vcd_led");
> + if (IS_ERR(dp_panel->bck_fet))
> + return PTR_ERR(dp_panel->bck_fet);
> +
> + if (gpio_is_valid(dp_panel->lcd_en_gpio)) {
> + ret = devm_gpio_request_one(dev, dp_panel->lcd_en_gpio,
> + GPIOF_OUT_INIT_LOW, "lcd_en_gpio");
> + if (ret) {
> + DRM_ERROR("failed to get lcd-en gpio [%d]\n", ret);
> + return ret;
> + }
> + } else {
> + dp_panel->lcd_en_gpio = -ENODEV;
> + }
> +
> + if (gpio_is_valid(dp_panel->led_en_gpio)) {
> + ret = devm_gpio_request_one(dev, dp_panel->led_en_gpio,
> + GPIOF_OUT_INIT_LOW, "led_en_gpio");
> + if (ret) {
> + DRM_ERROR("failed to get led-en gpio [%d]\n", ret);
> + return ret;
> + }
> + } else {
> + dp_panel->led_en_gpio = -ENODEV;
> + }
> +
> + drm_panel_init(&dp_panel->base);
> + dp_panel->base.dev = dev;
> + dp_panel->base.funcs = &panel_exynos_dp_funcs;
> +
> + ret = drm_panel_add(&dp_panel->base);
> + if (ret < 0)
> + return ret;
> +
> + dev_set_drvdata(dev, dp_panel);
> +
> + return 0;
> +}
> +
> +static int panel_exynos_dp_remove(struct platform_device *pdev)
> +{
> + struct panel_exynos_dp *dp_panel = dev_get_drvdata(&pdev->dev);
> +
> + drm_panel_detach(&dp_panel->base);
> + drm_panel_remove(&dp_panel->base);
> +
> + panel_exynos_dp_disable(&dp_panel->base);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id exynos_dp_panel_dt_match[] = {
> + { .compatible = "samsung,exynos-dp-panel" },
> + {},
> +};
> +
> +struct platform_driver exynos_dp_panel_driver = {
> + .driver = {
> + .name = "exynos-dp-panel",
> + .owner = THIS_MODULE,
> + .of_match_table = exynos_dp_panel_dt_match,
> + },
> + .probe = panel_exynos_dp_probe,
> + .remove = panel_exynos_dp_remove,
> +};
> --
> 1.8.1.2