// SPDX-License-Identifier: GPL-2.0-only
/*
 *  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 <eric.miao@marvell.com>
 */

#include <linux/backlight.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.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) <= LCD_POWER_REDUCED)

/* 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];

        struct gpio_desc *backlight_on;
        struct gpio_desc *backlight_cont;

        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      = 0,
                .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, u32 xres, u32 yres)
{
        struct corgi_lcd *lcd = lcd_get_data(ld);
        int mode = CORGI_LCD_MODE_QVGA;

        if (xres == 640 || 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 = lcd_get_data(ld);

        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 = lcd_get_data(ld);

        return lcd->power;
}

static const 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 = bl_get_data(bd);

        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);

        if (lcd->backlight_cont)
                gpiod_set_value_cansleep(lcd->backlight_cont, cont);

        if (lcd->backlight_on)
                gpiod_set_value_cansleep(lcd->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 = bl_get_data(bd);
        int intensity = backlight_get_brightness(bd);

        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_SLEEP
static int corgi_lcd_suspend(struct device *dev)
{
        struct corgi_lcd *lcd = dev_get_drvdata(dev);

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

static int corgi_lcd_resume(struct device *dev)
{
        struct corgi_lcd *lcd = dev_get_drvdata(dev);

        corgibl_flags &= ~CORGIBL_SUSPENDED;
        corgi_lcd_set_power(lcd->lcd_dev, LCD_POWER_ON);
        backlight_update_status(lcd->bl_dev);
        return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(corgi_lcd_pm_ops, corgi_lcd_suspend, corgi_lcd_resume);

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

        lcd->backlight_on = devm_gpiod_get_optional(&spi->dev,
                                                    "BL_ON", GPIOD_OUT_LOW);
        if (IS_ERR(lcd->backlight_on))
                return PTR_ERR(lcd->backlight_on);

        lcd->backlight_cont = devm_gpiod_get_optional(&spi->dev, "BL_CONT",
                                                      GPIOD_OUT_LOW);
        if (IS_ERR(lcd->backlight_cont))
                return PTR_ERR(lcd->backlight_cont);

        return 0;
}

static int corgi_lcd_probe(struct spi_device *spi)
{
        struct backlight_properties props;
        struct corgi_lcd_platform_data *pdata = dev_get_platdata(&spi->dev);
        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)
                return -ENOMEM;

        lcd->spi_dev = spi;

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

        lcd->power = LCD_POWER_OFF;
        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 = devm_backlight_device_register(&spi->dev, "corgi_bl",
                                                &spi->dev, lcd, &corgi_bl_ops,
                                                &props);
        if (IS_ERR(lcd->bl_dev))
                return PTR_ERR(lcd->bl_dev);

        lcd->bl_dev->props.brightness = pdata->default_intensity;
        lcd->bl_dev->props.power = BACKLIGHT_POWER_ON;

        ret = setup_gpio_backlight(lcd, pdata);
        if (ret)
                return ret;

        lcd->kick_battery = pdata->kick_battery;

        spi_set_drvdata(spi, lcd);
        corgi_lcd_set_power(lcd->lcd_dev, LCD_POWER_ON);
        backlight_update_status(lcd->bl_dev);

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

static void corgi_lcd_remove(struct spi_device *spi)
{
        struct corgi_lcd *lcd = spi_get_drvdata(spi);

        lcd->bl_dev->props.power = BACKLIGHT_POWER_ON;
        lcd->bl_dev->props.brightness = 0;
        backlight_update_status(lcd->bl_dev);
        corgi_lcd_set_power(lcd->lcd_dev, LCD_POWER_OFF);
}

static struct spi_driver corgi_lcd_driver = {
        .driver         = {
                .name   = "corgi-lcd",
                .pm     = &corgi_lcd_pm_ops,
        },
        .probe          = corgi_lcd_probe,
        .remove         = corgi_lcd_remove,
};

module_spi_driver(corgi_lcd_driver);

MODULE_DESCRIPTION("LCD and backlight driver for SHARP C7x0/Cxx00");
MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("spi:corgi-lcd");