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");
+