backlight: add support for Sharp SL-6000 LCD and backlight drivers

On Sharp SL-6000 lcd/backlight is a bit complex, so add two drivers
one for lcd-driving chip, other one for dac regulating the backlight
LEDS.

Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>

1 files changed, 280 insertions, 0 deletions

diff --git a/drivers/video/backlight/tosa_lcd.c b/drivers/video/backlight/tosa_lcd.c
new file mode 100644
index 000000000000..57a26649f1a5
--- /dev/null
+++ b/drivers/video/backlight/tosa_lcd.c
@@ -0,0 +1,280 @@
+/*
+ *  LCD / Backlight control code for Sharp SL-6000x (tosa)
+ *
+ *  Copyright (c) 2005		Dirk Opfer
+ *  Copyright (c) 2007,2008	Dmitry Baryshkov
+ *
+ *  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/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/spi/spi.h>
+#include <linux/i2c.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <linux/lcd.h>
+#include <linux/fb.h>
+
+#include <asm/mach/sharpsl_param.h>
+
+#include <mach/tosa.h>
+
+#define POWER_IS_ON(pwr)	((pwr) <= FB_BLANK_NORMAL)
+
+#define TG_REG0_VQV	0x0001
+#define TG_REG0_COLOR	0x0002
+#define TG_REG0_UD	0x0004
+#define TG_REG0_LR	0x0008
+
+#define	DAC_BASE	0x4e
+
+struct tosa_lcd_data {
+	struct spi_device *spi;
+	struct lcd_device *lcd;
+	struct i2c_client *i2c;
+
+	int lcd_power;
+};
+
+static int tosa_tg_send(struct spi_device *spi, int adrs, uint8_t data)
+{
+	u8 buf[1];
+	struct spi_message msg;
+	struct spi_transfer xfer = {
+		.len		= 1,
+		.cs_change	= 1,
+		.tx_buf		= buf,
+	};
+
+	buf[0] = ((adrs & 0x07) << 5) | (data & 0x1f);
+	spi_message_init(&msg);
+	spi_message_add_tail(&xfer, &msg);
+
+	return spi_sync(spi, &msg);
+}
+
+int tosa_bl_enable(struct spi_device *spi, int enable)
+{
+	/* bl_enable GP04=1 otherwise GP04=0*/
+	return tosa_tg_send(spi, TG_GPODR2, enable? 0x01 : 0x00);
+}
+EXPORT_SYMBOL(tosa_bl_enable);
+
+static void tosa_lcd_tg_init(struct tosa_lcd_data *data)
+{
+	/* TG on */
+	gpio_set_value(TOSA_GPIO_TG_ON, 0);
+
+	mdelay(60);
+
+	/* delayed 0clk TCTL signal for VGA */
+	tosa_tg_send(data->spi, TG_TPOSCTL, 0x00);
+	/* GPOS0=powercontrol, GPOS1=GPIO, GPOS2=TCTL */
+	tosa_tg_send(data->spi, TG_GPOSR, 0x02);
+}
+
+static void tosa_lcd_tg_on(struct tosa_lcd_data *data)
+{
+	struct spi_device *spi = data->spi;
+	const int value = TG_REG0_COLOR | TG_REG0_UD | TG_REG0_LR;
+	tosa_tg_send(spi, TG_PNLCTL, value | TG_REG0_VQV); /* this depends on mode */
+
+	/* TG LCD pannel power up */
+	tosa_tg_send(spi, TG_PINICTL,0x4);
+	mdelay(50);
+
+	/* TG LCD GVSS */
+	tosa_tg_send(spi, TG_PINICTL,0x0);
+
+	if (!data->i2c) {
+		/* after the pannel is powered up the first time, we can access the i2c bus */
+		/* so probe for the DAC */
+		struct i2c_adapter *adap = i2c_get_adapter(0);
+		struct i2c_board_info info = {
+			.type	= "tosa-bl",
+			.addr	= DAC_BASE,
+			.platform_data = data->spi,
+		};
+		data->i2c = i2c_new_device(adap, &info);
+	}
+}
+
+static void tosa_lcd_tg_off(struct tosa_lcd_data *data)
+{
+	struct spi_device *spi = data->spi;
+
+	/* TG LCD VHSA off */
+	tosa_tg_send(spi, TG_PINICTL,0x4);
+	mdelay(50);
+
+	/* TG LCD signal off */
+	tosa_tg_send(spi, TG_PINICTL,0x6);
+	mdelay(50);
+
+	/* TG Off */
+	gpio_set_value(TOSA_GPIO_TG_ON, 1);
+	mdelay(100);
+}
+
+int tosa_lcd_set_power(struct lcd_device *lcd, int power)
+{
+	struct tosa_lcd_data *data = lcd_get_data(lcd);
+
+	if (POWER_IS_ON(power) && !POWER_IS_ON(data->lcd_power))
+		tosa_lcd_tg_on(data);
+
+	if (!POWER_IS_ON(power) && POWER_IS_ON(data->lcd_power))
+		tosa_lcd_tg_off(data);
+
+	data->lcd_power = power;
+	return 0;
+}
+
+static int tosa_lcd_get_power(struct lcd_device *lcd)
+{
+	struct tosa_lcd_data *data = lcd_get_data(lcd);
+
+	return data->lcd_power;
+}
+
+static struct lcd_ops tosa_lcd_ops = {
+	.set_power = tosa_lcd_set_power,
+	.get_power = tosa_lcd_get_power,
+};
+
+static int __devinit tosa_lcd_probe(struct spi_device *spi)
+{
+	int ret;
+	struct tosa_lcd_data *data;
+
+	data = kzalloc(sizeof(struct tosa_lcd_data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	/*
+	 * bits_per_word cannot be configured in platform data
+	 */
+	spi->bits_per_word = 8;
+
+	ret = spi_setup(spi);
+	if (ret < 0)
+		goto err_spi;
+
+	data->spi = spi;
+	dev_set_drvdata(&spi->dev, data);
+
+	ret = gpio_request(TOSA_GPIO_TG_ON, "tg #pwr");
+	if (ret < 0)
+		goto err_gpio_tg;
+
+	mdelay(60);
+
+	ret = gpio_direction_output(TOSA_GPIO_TG_ON, 0);
+	if (ret < 0)
+		goto err_gpio_dir;
+
+	mdelay(60);
+	tosa_lcd_tg_init(data);
+
+	tosa_lcd_tg_on(data);
+
+	data->lcd = lcd_device_register("tosa-lcd", &spi->dev, data,
+			&tosa_lcd_ops);
+
+	if (IS_ERR(data->lcd)) {
+		ret = PTR_ERR(data->lcd);
+		data->lcd = NULL;
+		goto err_register;
+	}
+
+	return 0;
+
+err_register:
+	tosa_lcd_tg_off(data);
+err_gpio_dir:
+	gpio_free(TOSA_GPIO_TG_ON);
+err_gpio_tg:
+	dev_set_drvdata(&spi->dev, NULL);
+err_spi:
+	kfree(data);
+	return ret;
+}
+
+static int __devexit tosa_lcd_remove(struct spi_device *spi)
+{
+	struct tosa_lcd_data *data = dev_get_drvdata(&spi->dev);
+
+	lcd_device_unregister(data->lcd);
+
+	if (data->i2c)
+		i2c_unregister_device(data->i2c);
+
+	tosa_lcd_tg_off(data);
+
+	gpio_free(TOSA_GPIO_TG_ON);
+	dev_set_drvdata(&spi->dev, NULL);
+	kfree(data);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int tosa_lcd_suspend(struct spi_device *spi, pm_message_t state)
+{
+	struct tosa_lcd_data *data = dev_get_drvdata(&spi->dev);
+
+	tosa_lcd_tg_off(data);
+
+	return 0;
+}
+
+static int tosa_lcd_resume(struct spi_device *spi)
+{
+	struct tosa_lcd_data *data = dev_get_drvdata(&spi->dev);
+
+	tosa_lcd_tg_init(data);
+	if (POWER_IS_ON(data->lcd_power))
+		tosa_lcd_tg_on(data);
+	else
+		tosa_lcd_tg_off(data);
+
+	return 0;
+}
+#else
+#define tosa_lcd_suspend	NULL
+#define tosa_lcd_reume NULL
+#endif
+
+static struct spi_driver tosa_lcd_driver = {
+	.driver = {
+		.name		= "tosa-lcd",
+		.owner		= THIS_MODULE,
+	},
+	.probe		= tosa_lcd_probe,
+	.remove		= __devexit_p(tosa_lcd_remove),
+	.suspend	= tosa_lcd_suspend,
+	.resume		= tosa_lcd_resume,
+};
+
+static int __init tosa_lcd_init(void)
+{
+	return spi_register_driver(&tosa_lcd_driver);
+}
+
+static void __exit tosa_lcd_exit(void)
+{
+	spi_unregister_driver(&tosa_lcd_driver);
+}
+
+module_init(tosa_lcd_init);
+module_exit(tosa_lcd_exit);
+
+MODULE_AUTHOR("Dmitry Baryshkov");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("LCD/Backlight control for Sharp SL-6000 PDA");
+