tosa_lcd.c

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/*
 *  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/slab.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;
    bool is_vga;
};

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;
    int value = TG_REG0_COLOR | TG_REG0_UD | TG_REG0_LR;

    if (data->is_vga)
        value |= TG_REG0_VQV;

    tosa_tg_send(spi, TG_PNLCTL, value);

    /* 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 int tosa_lcd_set_mode(struct lcd_device *lcd, struct fb_videomode *mode)
{
    struct tosa_lcd_data *data = lcd_get_data(lcd);

    if (mode->xres == 320 || mode->yres == 320)
        data->is_vga = false;
    else
        data->is_vga = true;

    if (POWER_IS_ON(data->lcd_power))
        tosa_lcd_tg_on(data);

    return 0;
}

static struct lcd_ops tosa_lcd_ops = {
    .set_power = tosa_lcd_set_power,
    .get_power = tosa_lcd_get_power,
    .set_mode = tosa_lcd_set_mode,
};

static int __devinit tosa_lcd_probe(struct spi_device *spi)
{
    int ret;
    struct tosa_lcd_data *data;

    data = devm_kzalloc(&spi->dev, sizeof(struct tosa_lcd_data),
                GFP_KERNEL);
    if (!data)
        return -ENOMEM;

    data->is_vga = true; /* default to VGA mode */

    /*
     * bits_per_word cannot be configured in platform data
     */
    spi->bits_per_word = 8;

    ret = spi_setup(spi);
    if (ret < 0)
        return ret;

    data->spi = spi;
    dev_set_drvdata(&spi->dev, data);

    ret = devm_gpio_request(&spi->dev, 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_tg;

    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_tg:
    dev_set_drvdata(&spi->dev, NULL);
    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);

    dev_set_drvdata(&spi->dev, NULL);

    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_resume 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,
};

module_spi_driver(tosa_lcd_driver);

MODULE_AUTHOR("Dmitry Baryshkov");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("LCD/Backlight control for Sharp SL-6000 PDA");
MODULE_ALIAS("spi:tosa-lcd");