1 files changed, 269 insertions, 0 deletions

diff --git a/drivers/video/backlight/l4f00242t03.c b/drivers/video/backlight/l4f00242t03.c
new file mode 100644
index 000000000..5fa2649c9
--- /dev/null
+++ b/drivers/video/backlight/l4f00242t03.c
@@ -0,0 +1,269 @@
+/*
+ * l4f00242t03.c -- support for Epson L4F00242T03 LCD
+ *
+ * Copyright 2007-2009 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * Copyright (c) 2009 Alberto Panizzo <maramaopercheseimorto@gmail.com>
+ *	Inspired by Marek Vasut work in l4f00242t03.c
+ *
+ * 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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/gpio.h>
+#include <linux/lcd.h>
+#include <linux/slab.h>
+#include <linux/regulator/consumer.h>
+
+#include <linux/spi/spi.h>
+#include <linux/spi/l4f00242t03.h>
+
+struct l4f00242t03_priv {
+	struct spi_device	*spi;
+	struct lcd_device	*ld;
+	int lcd_state;
+	struct regulator *io_reg;
+	struct regulator *core_reg;
+};
+
+static void l4f00242t03_reset(unsigned int gpio)
+{
+	pr_debug("l4f00242t03_reset.\n");
+	gpio_set_value(gpio, 1);
+	mdelay(100);
+	gpio_set_value(gpio, 0);
+	mdelay(10);	/* tRES >= 100us */
+	gpio_set_value(gpio, 1);
+	mdelay(20);
+}
+
+#define param(x) ((x) | 0x100)
+
+static void l4f00242t03_lcd_init(struct spi_device *spi)
+{
+	struct l4f00242t03_pdata *pdata = dev_get_platdata(&spi->dev);
+	struct l4f00242t03_priv *priv = spi_get_drvdata(spi);
+	const u16 cmd[] = { 0x36, param(0), 0x3A, param(0x60) };
+	int ret;
+
+	dev_dbg(&spi->dev, "initializing LCD\n");
+
+	ret = regulator_set_voltage(priv->io_reg, 1800000, 1800000);
+	if (ret) {
+		dev_err(&spi->dev, "failed to set the IO regulator voltage.\n");
+		return;
+	}
+	ret = regulator_enable(priv->io_reg);
+	if (ret) {
+		dev_err(&spi->dev, "failed to enable the IO regulator.\n");
+		return;
+	}
+
+	ret = regulator_set_voltage(priv->core_reg, 2800000, 2800000);
+	if (ret) {
+		dev_err(&spi->dev, "failed to set the core regulator voltage.\n");
+		regulator_disable(priv->io_reg);
+		return;
+	}
+	ret = regulator_enable(priv->core_reg);
+	if (ret) {
+		dev_err(&spi->dev, "failed to enable the core regulator.\n");
+		regulator_disable(priv->io_reg);
+		return;
+	}
+
+	l4f00242t03_reset(pdata->reset_gpio);
+
+	gpio_set_value(pdata->data_enable_gpio, 1);
+	msleep(60);
+	spi_write(spi, (const u8 *)cmd, ARRAY_SIZE(cmd) * sizeof(u16));
+}
+
+static void l4f00242t03_lcd_powerdown(struct spi_device *spi)
+{
+	struct l4f00242t03_pdata *pdata = dev_get_platdata(&spi->dev);
+	struct l4f00242t03_priv *priv = spi_get_drvdata(spi);
+
+	dev_dbg(&spi->dev, "Powering down LCD\n");
+
+	gpio_set_value(pdata->data_enable_gpio, 0);
+
+	regulator_disable(priv->io_reg);
+	regulator_disable(priv->core_reg);
+}
+
+static int l4f00242t03_lcd_power_get(struct lcd_device *ld)
+{
+	struct l4f00242t03_priv *priv = lcd_get_data(ld);
+
+	return priv->lcd_state;
+}
+
+static int l4f00242t03_lcd_power_set(struct lcd_device *ld, int power)
+{
+	struct l4f00242t03_priv *priv = lcd_get_data(ld);
+	struct spi_device *spi = priv->spi;
+
+	const u16 slpout = 0x11;
+	const u16 dison = 0x29;
+
+	const u16 slpin = 0x10;
+	const u16 disoff = 0x28;
+
+	if (power <= FB_BLANK_NORMAL) {
+		if (priv->lcd_state <= FB_BLANK_NORMAL) {
+			/* Do nothing, the LCD is running */
+		} else if (priv->lcd_state < FB_BLANK_POWERDOWN) {
+			dev_dbg(&spi->dev, "Resuming LCD\n");
+
+			spi_write(spi, (const u8 *)&slpout, sizeof(u16));
+			msleep(60);
+			spi_write(spi, (const u8 *)&dison, sizeof(u16));
+		} else {
+			/* priv->lcd_state == FB_BLANK_POWERDOWN */
+			l4f00242t03_lcd_init(spi);
+			priv->lcd_state = FB_BLANK_VSYNC_SUSPEND;
+			l4f00242t03_lcd_power_set(priv->ld, power);
+		}
+	} else if (power < FB_BLANK_POWERDOWN) {
+		if (priv->lcd_state <= FB_BLANK_NORMAL) {
+			/* Send the display in standby */
+			dev_dbg(&spi->dev, "Standby the LCD\n");
+
+			spi_write(spi, (const u8 *)&disoff, sizeof(u16));
+			msleep(60);
+			spi_write(spi, (const u8 *)&slpin, sizeof(u16));
+		} else if (priv->lcd_state < FB_BLANK_POWERDOWN) {
+			/* Do nothing, the LCD is already in standby */
+		} else {
+			/* priv->lcd_state == FB_BLANK_POWERDOWN */
+			l4f00242t03_lcd_init(spi);
+			priv->lcd_state = FB_BLANK_UNBLANK;
+			l4f00242t03_lcd_power_set(ld, power);
+		}
+	} else {
+		/* power == FB_BLANK_POWERDOWN */
+		if (priv->lcd_state != FB_BLANK_POWERDOWN) {
+			/* Clear the screen before shutting down */
+			spi_write(spi, (const u8 *)&disoff, sizeof(u16));
+			msleep(60);
+			l4f00242t03_lcd_powerdown(spi);
+		}
+	}
+
+	priv->lcd_state = power;
+
+	return 0;
+}
+
+static struct lcd_ops l4f_ops = {
+	.set_power	= l4f00242t03_lcd_power_set,
+	.get_power	= l4f00242t03_lcd_power_get,
+};
+
+static int l4f00242t03_probe(struct spi_device *spi)
+{
+	struct l4f00242t03_priv *priv;
+	struct l4f00242t03_pdata *pdata = dev_get_platdata(&spi->dev);
+	int ret;
+
+	if (pdata == NULL) {
+		dev_err(&spi->dev, "Uninitialized platform data.\n");
+		return -EINVAL;
+	}
+
+	priv = devm_kzalloc(&spi->dev, sizeof(struct l4f00242t03_priv),
+				GFP_KERNEL);
+	if (priv == NULL)
+		return -ENOMEM;
+
+	spi_set_drvdata(spi, priv);
+	spi->bits_per_word = 9;
+	spi_setup(spi);
+
+	priv->spi = spi;
+
+	ret = devm_gpio_request_one(&spi->dev, pdata->reset_gpio,
+			GPIOF_OUT_INIT_HIGH, "lcd l4f00242t03 reset");
+	if (ret) {
+		dev_err(&spi->dev,
+			"Unable to get the lcd l4f00242t03 reset gpio.\n");
+		return ret;
+	}
+
+	ret = devm_gpio_request_one(&spi->dev, pdata->data_enable_gpio,
+			GPIOF_OUT_INIT_LOW, "lcd l4f00242t03 data enable");
+	if (ret) {
+		dev_err(&spi->dev,
+			"Unable to get the lcd l4f00242t03 data en gpio.\n");
+		return ret;
+	}
+
+	priv->io_reg = devm_regulator_get(&spi->dev, "vdd");
+	if (IS_ERR(priv->io_reg)) {
+		dev_err(&spi->dev, "%s: Unable to get the IO regulator\n",
+		       __func__);
+		return PTR_ERR(priv->io_reg);
+	}
+
+	priv->core_reg = devm_regulator_get(&spi->dev, "vcore");
+	if (IS_ERR(priv->core_reg)) {
+		dev_err(&spi->dev, "%s: Unable to get the core regulator\n",
+		       __func__);
+		return PTR_ERR(priv->core_reg);
+	}
+
+	priv->ld = devm_lcd_device_register(&spi->dev, "l4f00242t03", &spi->dev,
+					priv, &l4f_ops);
+	if (IS_ERR(priv->ld))
+		return PTR_ERR(priv->ld);
+
+	/* Init the LCD */
+	l4f00242t03_lcd_init(spi);
+	priv->lcd_state = FB_BLANK_VSYNC_SUSPEND;
+	l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_UNBLANK);
+
+	dev_info(&spi->dev, "Epson l4f00242t03 lcd probed.\n");
+
+	return 0;
+}
+
+static int l4f00242t03_remove(struct spi_device *spi)
+{
+	struct l4f00242t03_priv *priv = spi_get_drvdata(spi);
+
+	l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN);
+	return 0;
+}
+
+static void l4f00242t03_shutdown(struct spi_device *spi)
+{
+	struct l4f00242t03_priv *priv = spi_get_drvdata(spi);
+
+	if (priv)
+		l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN);
+
+}
+
+static struct spi_driver l4f00242t03_driver = {
+	.driver = {
+		.name	= "l4f00242t03",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= l4f00242t03_probe,
+	.remove		= l4f00242t03_remove,
+	.shutdown	= l4f00242t03_shutdown,
+};
+
+module_spi_driver(l4f00242t03_driver);
+
+MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto@gmail.com>");
+MODULE_DESCRIPTION("EPSON L4F00242T03 LCD");
+MODULE_LICENSE("GPL v2");