corgi_lcd.c

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/*
 *  LCD/Backlight Driver for Sharp Zaurus Handhelds (various models)
 *
 *  Copyright (c) 2004-2006 Richard Purdie
 *
 *  Based on Sharp's 2.4 Backlight Driver
 *
 *  Copyright (c) 2008 Marvell International Ltd.
 *      Converted to SPI device based LCD/Backlight device driver
 *      by Eric Miao <[email protected]>
 *
 *  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/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/fb.h>
#include <linux/lcd.h>
#include <linux/spi/spi.h>
#include <linux/spi/corgi_lcd.h>
#include <linux/slab.h>
#include <asm/mach/sharpsl_param.h>

#define POWER_IS_ON(pwr)    ((pwr) <= FB_BLANK_NORMAL)

/* Register Addresses */
#define RESCTL_ADRS     0x00
#define PHACTRL_ADRS    0x01
#define DUTYCTRL_ADRS   0x02
#define POWERREG0_ADRS  0x03
#define POWERREG1_ADRS  0x04
#define GPOR3_ADRS      0x05
#define PICTRL_ADRS     0x06
#define POLCTRL_ADRS    0x07

/* Register Bit Definitions */
#define RESCTL_QVGA     0x01
#define RESCTL_VGA      0x00

#define POWER1_VW_ON    0x01  /* VW Supply FET ON */
#define POWER1_GVSS_ON  0x02  /* GVSS(-8V) Power Supply ON */
#define POWER1_VDD_ON   0x04  /* VDD(8V),SVSS(-4V) Power Supply ON */

#define POWER1_VW_OFF   0x00  /* VW Supply FET OFF */
#define POWER1_GVSS_OFF 0x00  /* GVSS(-8V) Power Supply OFF */
#define POWER1_VDD_OFF  0x00  /* VDD(8V),SVSS(-4V) Power Supply OFF */

#define POWER0_COM_DCLK 0x01  /* COM Voltage DC Bias DAC Serial Data Clock */
#define POWER0_COM_DOUT 0x02  /* COM Voltage DC Bias DAC Serial Data Out */
#define POWER0_DAC_ON   0x04  /* DAC Power Supply ON */
#define POWER0_COM_ON   0x08  /* COM Power Supply ON */
#define POWER0_VCC5_ON  0x10  /* VCC5 Power Supply ON */

#define POWER0_DAC_OFF  0x00  /* DAC Power Supply OFF */
#define POWER0_COM_OFF  0x00  /* COM Power Supply OFF */
#define POWER0_VCC5_OFF 0x00  /* VCC5 Power Supply OFF */

#define PICTRL_INIT_STATE      0x01
#define PICTRL_INIOFF          0x02
#define PICTRL_POWER_DOWN      0x04
#define PICTRL_COM_SIGNAL_OFF  0x08
#define PICTRL_DAC_SIGNAL_OFF  0x10

#define POLCTRL_SYNC_POL_FALL  0x01
#define POLCTRL_EN_POL_FALL    0x02
#define POLCTRL_DATA_POL_FALL  0x04
#define POLCTRL_SYNC_ACT_H     0x08
#define POLCTRL_EN_ACT_L       0x10

#define POLCTRL_SYNC_POL_RISE  0x00
#define POLCTRL_EN_POL_RISE    0x00
#define POLCTRL_DATA_POL_RISE  0x00
#define POLCTRL_SYNC_ACT_L     0x00
#define POLCTRL_EN_ACT_H       0x00

#define PHACTRL_PHASE_MANUAL   0x01
#define DEFAULT_PHAD_QVGA     (9)
#define DEFAULT_COMADJ        (125)

struct corgi_lcd {
    struct spi_device   *spi_dev;
    struct lcd_device   *lcd_dev;
    struct backlight_device *bl_dev;

    int limit_mask;
    int intensity;
    int power;
    int mode;
    char    buf[2];

    int gpio_backlight_on;
    int gpio_backlight_cont;
    int gpio_backlight_cont_inverted;

    void (*kick_battery)(void);
};

static int corgi_ssp_lcdtg_send(struct corgi_lcd *lcd, int reg, uint8_t val);

static struct corgi_lcd *the_corgi_lcd;
static unsigned long corgibl_flags;
#define CORGIBL_SUSPENDED     0x01
#define CORGIBL_BATTLOW       0x02

/*
 * This is only a pseudo I2C interface. We can't use the standard kernel
 * routines as the interface is write only. We just assume the data is acked...
 */
static void lcdtg_ssp_i2c_send(struct corgi_lcd *lcd, uint8_t data)
{
    corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS, data);
    udelay(10);
}

static void lcdtg_i2c_send_bit(struct corgi_lcd *lcd, uint8_t data)
{
    lcdtg_ssp_i2c_send(lcd, data);
    lcdtg_ssp_i2c_send(lcd, data | POWER0_COM_DCLK);
    lcdtg_ssp_i2c_send(lcd, data);
}

static void lcdtg_i2c_send_start(struct corgi_lcd *lcd, uint8_t base)
{
    lcdtg_ssp_i2c_send(lcd, base | POWER0_COM_DCLK | POWER0_COM_DOUT);
    lcdtg_ssp_i2c_send(lcd, base | POWER0_COM_DCLK);
    lcdtg_ssp_i2c_send(lcd, base);
}

static void lcdtg_i2c_send_stop(struct corgi_lcd *lcd, uint8_t base)
{
    lcdtg_ssp_i2c_send(lcd, base);
    lcdtg_ssp_i2c_send(lcd, base | POWER0_COM_DCLK);
    lcdtg_ssp_i2c_send(lcd, base | POWER0_COM_DCLK | POWER0_COM_DOUT);
}

static void lcdtg_i2c_send_byte(struct corgi_lcd *lcd,
                uint8_t base, uint8_t data)
{
    int i;
    for (i = 0; i < 8; i++) {
        if (data & 0x80)
            lcdtg_i2c_send_bit(lcd, base | POWER0_COM_DOUT);
        else
            lcdtg_i2c_send_bit(lcd, base);
        data <<= 1;
    }
}

static void lcdtg_i2c_wait_ack(struct corgi_lcd *lcd, uint8_t base)
{
    lcdtg_i2c_send_bit(lcd, base);
}

static void lcdtg_set_common_voltage(struct corgi_lcd *lcd,
                     uint8_t base_data, uint8_t data)
{
    /* Set Common Voltage to M62332FP via I2C */
    lcdtg_i2c_send_start(lcd, base_data);
    lcdtg_i2c_send_byte(lcd, base_data, 0x9c);
    lcdtg_i2c_wait_ack(lcd, base_data);
    lcdtg_i2c_send_byte(lcd, base_data, 0x00);
    lcdtg_i2c_wait_ack(lcd, base_data);
    lcdtg_i2c_send_byte(lcd, base_data, data);
    lcdtg_i2c_wait_ack(lcd, base_data);
    lcdtg_i2c_send_stop(lcd, base_data);
}

static int corgi_ssp_lcdtg_send(struct corgi_lcd *lcd, int adrs, uint8_t data)
{
    struct spi_message msg;
    struct spi_transfer xfer = {
        .len        = 1,
        .cs_change  = 1,
        .tx_buf     = lcd->buf,
    };

    lcd->buf[0] = ((adrs & 0x07) << 5) | (data & 0x1f);
    spi_message_init(&msg);
    spi_message_add_tail(&xfer, &msg);

    return spi_sync(lcd->spi_dev, &msg);
}

/* Set Phase Adjust */
static void lcdtg_set_phadadj(struct corgi_lcd *lcd, int mode)
{
    int adj;

    switch(mode) {
    case CORGI_LCD_MODE_VGA:
        /* Setting for VGA */
        adj = sharpsl_param.phadadj;
        adj = (adj < 0) ? PHACTRL_PHASE_MANUAL :
                  PHACTRL_PHASE_MANUAL | ((adj & 0xf) << 1);
        break;
    case CORGI_LCD_MODE_QVGA:
    default:
        /* Setting for QVGA */
        adj = (DEFAULT_PHAD_QVGA << 1) | PHACTRL_PHASE_MANUAL;
        break;
    }

    corgi_ssp_lcdtg_send(lcd, PHACTRL_ADRS, adj);
}

static void corgi_lcd_power_on(struct corgi_lcd *lcd)
{
    int comadj;

    /* Initialize Internal Logic & Port */
    corgi_ssp_lcdtg_send(lcd, PICTRL_ADRS,
            PICTRL_POWER_DOWN | PICTRL_INIOFF |
            PICTRL_INIT_STATE | PICTRL_COM_SIGNAL_OFF |
            PICTRL_DAC_SIGNAL_OFF);

    corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS,
            POWER0_COM_DCLK | POWER0_COM_DOUT | POWER0_DAC_OFF |
            POWER0_COM_OFF | POWER0_VCC5_OFF);

    corgi_ssp_lcdtg_send(lcd, POWERREG1_ADRS,
            POWER1_VW_OFF | POWER1_GVSS_OFF | POWER1_VDD_OFF);

    /* VDD(+8V), SVSS(-4V) ON */
    corgi_ssp_lcdtg_send(lcd, POWERREG1_ADRS,
            POWER1_VW_OFF | POWER1_GVSS_OFF | POWER1_VDD_ON);
    mdelay(3);

    /* DAC ON */
    corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS,
            POWER0_COM_DCLK | POWER0_COM_DOUT | POWER0_DAC_ON |
            POWER0_COM_OFF | POWER0_VCC5_OFF);

    /* INIB = H, INI = L  */
    /* PICTL[0] = H , PICTL[1] = PICTL[2] = PICTL[4] = L */
    corgi_ssp_lcdtg_send(lcd, PICTRL_ADRS,
            PICTRL_INIT_STATE | PICTRL_COM_SIGNAL_OFF);

    /* Set Common Voltage */
    comadj = sharpsl_param.comadj;
    if (comadj < 0)
        comadj = DEFAULT_COMADJ;

    lcdtg_set_common_voltage(lcd, POWER0_DAC_ON | POWER0_COM_OFF |
                 POWER0_VCC5_OFF, comadj);

    /* VCC5 ON, DAC ON */
    corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS,
            POWER0_COM_DCLK | POWER0_COM_DOUT | POWER0_DAC_ON |
            POWER0_COM_OFF | POWER0_VCC5_ON);

    /* GVSS(-8V) ON, VDD ON */
    corgi_ssp_lcdtg_send(lcd, POWERREG1_ADRS,
            POWER1_VW_OFF | POWER1_GVSS_ON | POWER1_VDD_ON);
    mdelay(2);

    /* COM SIGNAL ON (PICTL[3] = L) */
    corgi_ssp_lcdtg_send(lcd, PICTRL_ADRS, PICTRL_INIT_STATE);

    /* COM ON, DAC ON, VCC5_ON */
    corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS,
            POWER0_COM_DCLK | POWER0_COM_DOUT | POWER0_DAC_ON |
            POWER0_COM_ON | POWER0_VCC5_ON);

    /* VW ON, GVSS ON, VDD ON */
    corgi_ssp_lcdtg_send(lcd, POWERREG1_ADRS,
            POWER1_VW_ON | POWER1_GVSS_ON | POWER1_VDD_ON);

    /* Signals output enable */
    corgi_ssp_lcdtg_send(lcd, PICTRL_ADRS, 0);

    /* Set Phase Adjust */
    lcdtg_set_phadadj(lcd, lcd->mode);

    /* Initialize for Input Signals from ATI */
    corgi_ssp_lcdtg_send(lcd, POLCTRL_ADRS,
            POLCTRL_SYNC_POL_RISE | POLCTRL_EN_POL_RISE |
            POLCTRL_DATA_POL_RISE | POLCTRL_SYNC_ACT_L |
            POLCTRL_EN_ACT_H);
    udelay(1000);

    switch (lcd->mode) {
    case CORGI_LCD_MODE_VGA:
        corgi_ssp_lcdtg_send(lcd, RESCTL_ADRS, RESCTL_VGA);
        break;
    case CORGI_LCD_MODE_QVGA:
    default:
        corgi_ssp_lcdtg_send(lcd, RESCTL_ADRS, RESCTL_QVGA);
        break;
    }
}

static void corgi_lcd_power_off(struct corgi_lcd *lcd)
{
    /* 60Hz x 2 frame = 16.7msec x 2 = 33.4 msec */
    msleep(34);

    /* (1)VW OFF */
    corgi_ssp_lcdtg_send(lcd, POWERREG1_ADRS,
            POWER1_VW_OFF | POWER1_GVSS_ON | POWER1_VDD_ON);

    /* (2)COM OFF */
    corgi_ssp_lcdtg_send(lcd, PICTRL_ADRS, PICTRL_COM_SIGNAL_OFF);
    corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS,
            POWER0_DAC_ON | POWER0_COM_OFF | POWER0_VCC5_ON);

    /* (3)Set Common Voltage Bias 0V */
    lcdtg_set_common_voltage(lcd, POWER0_DAC_ON | POWER0_COM_OFF |
            POWER0_VCC5_ON, 0);

    /* (4)GVSS OFF */
    corgi_ssp_lcdtg_send(lcd, POWERREG1_ADRS,
            POWER1_VW_OFF | POWER1_GVSS_OFF | POWER1_VDD_ON);

    /* (5)VCC5 OFF */
    corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS,
            POWER0_DAC_ON | POWER0_COM_OFF | POWER0_VCC5_OFF);

    /* (6)Set PDWN, INIOFF, DACOFF */
    corgi_ssp_lcdtg_send(lcd, PICTRL_ADRS,
            PICTRL_INIOFF | PICTRL_DAC_SIGNAL_OFF |
            PICTRL_POWER_DOWN | PICTRL_COM_SIGNAL_OFF);

    /* (7)DAC OFF */
    corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS,
            POWER0_DAC_OFF | POWER0_COM_OFF | POWER0_VCC5_OFF);

    /* (8)VDD OFF */
    corgi_ssp_lcdtg_send(lcd, POWERREG1_ADRS,
            POWER1_VW_OFF | POWER1_GVSS_OFF | POWER1_VDD_OFF);
}

static int corgi_lcd_set_mode(struct lcd_device *ld, struct fb_videomode *m)
{
    struct corgi_lcd *lcd = dev_get_drvdata(&ld->dev);
    int mode = CORGI_LCD_MODE_QVGA;

    if (m->xres == 640 || m->xres == 480)
        mode = CORGI_LCD_MODE_VGA;

    if (lcd->mode == mode)
        return 0;

    lcdtg_set_phadadj(lcd, mode);

    switch (mode) {
    case CORGI_LCD_MODE_VGA:
        corgi_ssp_lcdtg_send(lcd, RESCTL_ADRS, RESCTL_VGA);
        break;
    case CORGI_LCD_MODE_QVGA:
    default:
        corgi_ssp_lcdtg_send(lcd, RESCTL_ADRS, RESCTL_QVGA);
        break;
    }

    lcd->mode = mode;
    return 0;
}

static int corgi_lcd_set_power(struct lcd_device *ld, int power)
{
    struct corgi_lcd *lcd = dev_get_drvdata(&ld->dev);

    if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power))
        corgi_lcd_power_on(lcd);

    if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power))
        corgi_lcd_power_off(lcd);

    lcd->power = power;
    return 0;
}

static int corgi_lcd_get_power(struct lcd_device *ld)
{
    struct corgi_lcd *lcd = dev_get_drvdata(&ld->dev);

    return lcd->power;
}

static struct lcd_ops corgi_lcd_ops = {
    .get_power  = corgi_lcd_get_power,
    .set_power  = corgi_lcd_set_power,
    .set_mode   = corgi_lcd_set_mode,
};

static int corgi_bl_get_intensity(struct backlight_device *bd)
{
    struct corgi_lcd *lcd = dev_get_drvdata(&bd->dev);

    return lcd->intensity;
}

static int corgi_bl_set_intensity(struct corgi_lcd *lcd, int intensity)
{
    int cont;

    if (intensity > 0x10)
        intensity += 0x10;

    corgi_ssp_lcdtg_send(lcd, DUTYCTRL_ADRS, intensity);

    /* Bit 5 via GPIO_BACKLIGHT_CONT */
    cont = !!(intensity & 0x20) ^ lcd->gpio_backlight_cont_inverted;

    if (gpio_is_valid(lcd->gpio_backlight_cont))
        gpio_set_value(lcd->gpio_backlight_cont, cont);

    if (gpio_is_valid(lcd->gpio_backlight_on))
        gpio_set_value(lcd->gpio_backlight_on, intensity);

    if (lcd->kick_battery)
        lcd->kick_battery();

    lcd->intensity = intensity;
    return 0;
}

static int corgi_bl_update_status(struct backlight_device *bd)
{
    struct corgi_lcd *lcd = dev_get_drvdata(&bd->dev);
    int intensity = bd->props.brightness;

    if (bd->props.power != FB_BLANK_UNBLANK)
        intensity = 0;

    if (bd->props.fb_blank != FB_BLANK_UNBLANK)
        intensity = 0;

    if (corgibl_flags & CORGIBL_SUSPENDED)
        intensity = 0;

    if ((corgibl_flags & CORGIBL_BATTLOW) && intensity > lcd->limit_mask)
        intensity = lcd->limit_mask;

    return corgi_bl_set_intensity(lcd, intensity);
}

void corgi_lcd_limit_intensity(int limit)
{
    if (limit)
        corgibl_flags |= CORGIBL_BATTLOW;
    else
        corgibl_flags &= ~CORGIBL_BATTLOW;

    backlight_update_status(the_corgi_lcd->bl_dev);
}
EXPORT_SYMBOL(corgi_lcd_limit_intensity);

static const struct backlight_ops corgi_bl_ops = {
    .get_brightness = corgi_bl_get_intensity,
    .update_status  = corgi_bl_update_status,
};

#ifdef CONFIG_PM
static int corgi_lcd_suspend(struct spi_device *spi, pm_message_t state)
{
    struct corgi_lcd *lcd = dev_get_drvdata(&spi->dev);

    corgibl_flags |= CORGIBL_SUSPENDED;
    corgi_bl_set_intensity(lcd, 0);
    corgi_lcd_set_power(lcd->lcd_dev, FB_BLANK_POWERDOWN);
    return 0;
}

static int corgi_lcd_resume(struct spi_device *spi)
{
    struct corgi_lcd *lcd = dev_get_drvdata(&spi->dev);

    corgibl_flags &= ~CORGIBL_SUSPENDED;
    corgi_lcd_set_power(lcd->lcd_dev, FB_BLANK_UNBLANK);
    backlight_update_status(lcd->bl_dev);
    return 0;
}
#else
#define corgi_lcd_suspend   NULL
#define corgi_lcd_resume    NULL
#endif

static int setup_gpio_backlight(struct corgi_lcd *lcd,
                struct corgi_lcd_platform_data *pdata)
{
    struct spi_device *spi = lcd->spi_dev;
    int err;

    lcd->gpio_backlight_on = -1;
    lcd->gpio_backlight_cont = -1;

    if (gpio_is_valid(pdata->gpio_backlight_on)) {
        err = devm_gpio_request(&spi->dev, pdata->gpio_backlight_on,
                    "BL_ON");
        if (err) {
            dev_err(&spi->dev, "failed to request GPIO%d for "
                "backlight_on\n", pdata->gpio_backlight_on);
            return err;
        }

        lcd->gpio_backlight_on = pdata->gpio_backlight_on;
        gpio_direction_output(lcd->gpio_backlight_on, 0);
    }

    if (gpio_is_valid(pdata->gpio_backlight_cont)) {
        err = devm_gpio_request(&spi->dev, pdata->gpio_backlight_cont,
                    "BL_CONT");
        if (err) {
            dev_err(&spi->dev, "failed to request GPIO%d for "
                "backlight_cont\n", pdata->gpio_backlight_cont);
            return err;
        }

        lcd->gpio_backlight_cont = pdata->gpio_backlight_cont;

        /* spitz and akita use both GPIOs for backlight, and
         * have inverted polarity of GPIO_BACKLIGHT_CONT
         */
        if (gpio_is_valid(lcd->gpio_backlight_on)) {
            lcd->gpio_backlight_cont_inverted = 1;
            gpio_direction_output(lcd->gpio_backlight_cont, 1);
        } else {
            lcd->gpio_backlight_cont_inverted = 0;
            gpio_direction_output(lcd->gpio_backlight_cont, 0);
        }
    }
    return 0;
}

static int __devinit corgi_lcd_probe(struct spi_device *spi)
{
    struct backlight_properties props;
    struct corgi_lcd_platform_data *pdata = spi->dev.platform_data;
    struct corgi_lcd *lcd;
    int ret = 0;

    if (pdata == NULL) {
        dev_err(&spi->dev, "platform data not available\n");
        return -EINVAL;
    }

    lcd = devm_kzalloc(&spi->dev, sizeof(struct corgi_lcd), GFP_KERNEL);
    if (!lcd) {
        dev_err(&spi->dev, "failed to allocate memory\n");
        return -ENOMEM;
    }

    lcd->spi_dev = spi;

    lcd->lcd_dev = lcd_device_register("corgi_lcd", &spi->dev,
                    lcd, &corgi_lcd_ops);
    if (IS_ERR(lcd->lcd_dev))
        return PTR_ERR(lcd->lcd_dev);

    lcd->power = FB_BLANK_POWERDOWN;
    lcd->mode = (pdata) ? pdata->init_mode : CORGI_LCD_MODE_VGA;

    memset(&props, 0, sizeof(struct backlight_properties));
    props.type = BACKLIGHT_RAW;
    props.max_brightness = pdata->max_intensity;
    lcd->bl_dev = backlight_device_register("corgi_bl", &spi->dev, lcd,
                        &corgi_bl_ops, &props);
    if (IS_ERR(lcd->bl_dev)) {
        ret = PTR_ERR(lcd->bl_dev);
        goto err_unregister_lcd;
    }
    lcd->bl_dev->props.brightness = pdata->default_intensity;
    lcd->bl_dev->props.power = FB_BLANK_UNBLANK;

    ret = setup_gpio_backlight(lcd, pdata);
    if (ret)
        goto err_unregister_bl;

    lcd->kick_battery = pdata->kick_battery;

    dev_set_drvdata(&spi->dev, lcd);
    corgi_lcd_set_power(lcd->lcd_dev, FB_BLANK_UNBLANK);
    backlight_update_status(lcd->bl_dev);

    lcd->limit_mask = pdata->limit_mask;
    the_corgi_lcd = lcd;
    return 0;

err_unregister_bl:
    backlight_device_unregister(lcd->bl_dev);
err_unregister_lcd:
    lcd_device_unregister(lcd->lcd_dev);
    return ret;
}

static int __devexit corgi_lcd_remove(struct spi_device *spi)
{
    struct corgi_lcd *lcd = dev_get_drvdata(&spi->dev);

    lcd->bl_dev->props.power = FB_BLANK_UNBLANK;
    lcd->bl_dev->props.brightness = 0;
    backlight_update_status(lcd->bl_dev);
    backlight_device_unregister(lcd->bl_dev);

    corgi_lcd_set_power(lcd->lcd_dev, FB_BLANK_POWERDOWN);
    lcd_device_unregister(lcd->lcd_dev);

    return 0;
}

static struct spi_driver corgi_lcd_driver = {
    .driver     = {
        .name   = "corgi-lcd",
        .owner  = THIS_MODULE,
    },
    .probe      = corgi_lcd_probe,
    .remove     = __devexit_p(corgi_lcd_remove),
    .suspend    = corgi_lcd_suspend,
    .resume     = corgi_lcd_resume,
};

module_spi_driver(corgi_lcd_driver);

MODULE_DESCRIPTION("LCD and backlight driver for SHARP C7x0/Cxx00");
MODULE_AUTHOR("Eric Miao <[email protected]>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("spi:corgi-lcd");