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Diffstat (limited to 'kernel/drivers/video/backlight/l4f00242t03.c')
-rw-r--r--kernel/drivers/video/backlight/l4f00242t03.c269
1 files changed, 269 insertions, 0 deletions
diff --git a/kernel/drivers/video/backlight/l4f00242t03.c b/kernel/drivers/video/backlight/l4f00242t03.c
new file mode 100644
index 000000000..5fa2649c9
--- /dev/null
+++ b/kernel/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");