Merge branch 'tracking-samslt-bl' into merge-linux-linaro

3 files changed, 234 insertions, 0 deletions

diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index 2979292650d6..588adc357583 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -86,6 +86,13 @@ config LCD_PLATFORM
 	  This driver provides a platform-device registered LCD power
 	  control interface.
 
+config LCD_PWRCTRL
+	tristate "LCD panel power control"
+	help
+	  Say y here, if you have a lcd panel that allows reset and vcc to be
+	  controlled by the host system, and which does not use a serial command
+	  interface (such as i2c or spi) or memory-mapped-io interface.
+
 config LCD_TOSA
 	tristate "Sharp SL-6000 LCD Driver"
 	depends on I2C && SPI && MACH_TOSA
diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
index a2ac9cfbaf6b..915650e01038 100644
--- a/drivers/video/backlight/Makefile
+++ b/drivers/video/backlight/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_LCD_LMS283GF05)	   += lms283gf05.o
 obj-$(CONFIG_LCD_LTV350QV)	   += ltv350qv.o
 obj-$(CONFIG_LCD_ILI9320)	   += ili9320.o
 obj-$(CONFIG_LCD_PLATFORM)	   += platform_lcd.o
+obj-$(CONFIG_LCD_PWRCTRL)	   += lcd_pwrctrl.o
 obj-$(CONFIG_LCD_VGG2432A4)	   += vgg2432a4.o
 obj-$(CONFIG_LCD_TDO24M)	   += tdo24m.o
 obj-$(CONFIG_LCD_TOSA)		   += tosa_lcd.o
diff --git a/drivers/video/backlight/lcd_pwrctrl.c b/drivers/video/backlight/lcd_pwrctrl.c
new file mode 100644
index 000000000000..917d842523c8
--- /dev/null
+++ b/drivers/video/backlight/lcd_pwrctrl.c
@@ -0,0 +1,226 @@
+/*
+ * Simple lcd panel power control driver.
+ *
+ * Copyright (c) 2011-2012 Samsung Electronics Co., Ltd.
+ * Copyright (c) 2011-2012 Linaro Ltd.
+ *
+ * This driver is for controlling power for raster type lcd panels that requires
+ * its nRESET interface line to be connected and controlled by a GPIO of the
+ * host system and the Vcc line controlled by a voltage regulator.  This
+ * excludes support for lcd panels that use a serial command interface or direct
+ * memory mapped IO interface.
+ *
+ * The nRESET interface line of the panel should be connected to a gpio of the
+ * host system. The Vcc pin is controlled using a external volatage regulator.
+ * Panel backlight is not controlled by this driver.
+ *
+ * This driver is derived from platform-lcd.c which was written by
+ * Ben Dooks <ben@simtec.co.uk>
+ *
+ * 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/module.h>
+#include <linux/platform_device.h>
+#include <linux/fb.h>
+#include <linux/lcd.h>
+#include <linux/gpio.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/regulator/consumer.h>
+#include <video/lcd_pwrctrl.h>
+
+struct lcd_pwrctrl {
+	struct device		*dev;
+	struct lcd_device	*lcd;
+	struct lcd_pwrctrl_data	*pdata;
+	struct regulator	*regulator;
+	unsigned int		power;
+	bool			suspended;
+	bool			pwr_en;
+};
+
+static int lcd_pwrctrl_get_power(struct lcd_device *lcd)
+{
+	struct lcd_pwrctrl *lp = lcd_get_data(lcd);
+	return lp->power;
+}
+
+static int lcd_pwrctrl_set_power(struct lcd_device *lcd, int power)
+{
+	struct lcd_pwrctrl *lp = lcd_get_data(lcd);
+	struct lcd_pwrctrl_data *pd = lp->pdata;
+	bool lcd_enable;
+	int lcd_reset, ret = 0;
+
+	lcd_enable = (power == FB_BLANK_POWERDOWN || lp->suspended) ? 0 : 1;
+	lcd_reset = (pd->invert) ? !lcd_enable : lcd_enable;
+
+	if (lp->pwr_en == lcd_enable)
+		return 0;
+
+	if (!IS_ERR_OR_NULL(lp->regulator)) {
+		if (lcd_enable) {
+			if (regulator_enable(lp->regulator)) {
+				dev_info(lp->dev, "regulator enable failed\n");
+				ret = -EPERM;
+			}
+		} else {
+			if (regulator_disable(lp->regulator)) {
+				dev_info(lp->dev, "regulator disable failed\n");
+				ret = -EPERM;
+			}
+		}
+	}
+
+	gpio_direction_output(lp->pdata->gpio, lcd_reset);
+	lp->power = power;
+	lp->pwr_en = lcd_enable;
+	return ret;
+}
+
+static int lcd_pwrctrl_check_fb(struct lcd_device *lcd, struct fb_info *info)
+{
+	struct lcd_pwrctrl *lp = lcd_get_data(lcd);
+	return lp->dev->parent == info->device;
+}
+
+static struct lcd_ops lcd_pwrctrl_ops = {
+	.get_power	= lcd_pwrctrl_get_power,
+	.set_power	= lcd_pwrctrl_set_power,
+	.check_fb	= lcd_pwrctrl_check_fb,
+};
+
+#ifdef CONFIG_OF
+static void __devinit lcd_pwrctrl_parse_dt(struct device *dev,
+					struct lcd_pwrctrl_data *pdata)
+{
+	struct device_node *np = dev->of_node;
+
+	pdata->gpio = of_get_named_gpio(np, "lcd-reset-gpio", 0);
+	if (of_get_property(np, "lcd-reset-active-high", NULL))
+		pdata->invert = true;
+}
+#endif
+
+static int __devinit lcd_pwrctrl_probe(struct platform_device *pdev)
+{
+	struct lcd_pwrctrl *lp;
+	struct lcd_pwrctrl_data *pdata = pdev->dev.platform_data;
+	struct device *dev = &pdev->dev;
+	int err;
+
+#ifdef CONFIG_OF
+	if (dev->of_node) {
+		pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+		if (!pdata) {
+			dev_err(dev, "memory allocation for pdata failed\n");
+			return -ENOMEM;
+		}
+		lcd_pwrctrl_parse_dt(dev, pdata);
+	}
+#endif
+
+	if (!pdata) {
+		dev_err(dev, "platform data not available\n");
+		return -EINVAL;
+	}
+
+	lp = devm_kzalloc(dev, sizeof(struct lcd_pwrctrl), GFP_KERNEL);
+	if (!lp) {
+		dev_err(dev, "memory allocation failed for private data\n");
+		return -ENOMEM;
+	}
+
+	err = gpio_request(pdata->gpio, "LCD-nRESET");
+	if (err) {
+		dev_err(dev, "gpio [%d] request failed\n", pdata->gpio);
+		return err;
+	}
+
+	/*
+	 * If power to lcd and/or lcd interface is controlled using a regulator,
+	 * get the handle to the regulator for later use during power switching.
+	 */
+	lp->regulator = devm_regulator_get(dev, "vcc-lcd");
+	if (IS_ERR(lp->regulator))
+		dev_info(dev, "could not find regulator\n");
+
+	lp->dev = dev;
+	lp->pdata = pdata;
+	lp->lcd = lcd_device_register(dev_name(dev), dev, lp, &lcd_pwrctrl_ops);
+	if (IS_ERR(lp->lcd)) {
+		dev_err(dev, "cannot register lcd device\n");
+		gpio_free(pdata->gpio);
+		return PTR_ERR(lp->lcd);
+	}
+
+	platform_set_drvdata(pdev, lp);
+	lcd_pwrctrl_set_power(lp->lcd, FB_BLANK_NORMAL);
+	return 0;
+}
+
+static int __devexit lcd_pwrctrl_remove(struct platform_device *pdev)
+{
+	struct lcd_pwrctrl *lp = platform_get_drvdata(pdev);
+	lcd_device_unregister(lp->lcd);
+	gpio_free(lp->pdata->gpio);
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int lcd_pwrctrl_suspend(struct device *dev)
+{
+	struct lcd_pwrctrl *lp = dev_get_drvdata(dev);
+
+	lp->suspended = true;
+	lcd_pwrctrl_set_power(lp->lcd, FB_BLANK_POWERDOWN);
+	return 0;
+}
+
+static int lcd_pwrctrl_resume(struct device *dev)
+{
+	struct lcd_pwrctrl *lp = dev_get_drvdata(dev);
+
+	lp->suspended = false;
+	lcd_pwrctrl_set_power(lp->lcd, FB_BLANK_UNBLANK);
+	return 0;
+}
+
+static const struct dev_pm_ops lcd_pwrctrl_dev_pm_ops = {
+	.suspend	= lcd_pwrctrl_suspend,
+	.resume		= lcd_pwrctrl_resume,
+};
+
+#define LCD_PWRCTRL_DEV_PM_OPS	(&lcd_pwrctrl_dev_pm_ops)
+#else
+#define LCD_PWRCTRL_DEV_PM_OPS	NULL
+#endif /* CONFIG_PM */
+
+#ifdef CONFIG_OF
+static const struct of_device_id lcd_pwrctrl_match[] = {
+	{ .compatible = "lcd-powercontrol", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, lcd_pwrctrl_match);
+#endif
+
+static struct platform_driver lcd_pwrctrl_driver = {
+	.driver		= {
+		.name	= "lcd-pwrctrl",
+		.owner	= THIS_MODULE,
+		.pm	= LCD_PWRCTRL_DEV_PM_OPS,
+		.of_match_table	= of_match_ptr(lcd_pwrctrl_match),
+	},
+	.probe		= lcd_pwrctrl_probe,
+	.remove		= lcd_pwrctrl_remove,
+};
+
+module_platform_driver(lcd_pwrctrl_driver);
+
+MODULE_AUTHOR("Thomas Abraham <thomas.ab@samsung.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:lcd-pwrctrl");