panel-tpo-td043mtea1.c

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/*
 * LCD panel driver for TPO TD043MTEA1
 *
 * Author: Gražvydas Ignotas <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/delay.h>
#include <linux/spi/spi.h>
#include <linux/regulator/consumer.h>
#include <linux/gpio.h>
#include <linux/err.h>
#include <linux/slab.h>

#include <video/omapdss.h>

#define TPO_R02_MODE(x)     ((x) & 7)
#define TPO_R02_MODE_800x480    7
#define TPO_R02_NCLK_RISING BIT(3)
#define TPO_R02_HSYNC_HIGH  BIT(4)
#define TPO_R02_VSYNC_HIGH  BIT(5)

#define TPO_R03_NSTANDBY    BIT(0)
#define TPO_R03_EN_CP_CLK   BIT(1)
#define TPO_R03_EN_VGL_PUMP BIT(2)
#define TPO_R03_EN_PWM      BIT(3)
#define TPO_R03_DRIVING_CAP_100 BIT(4)
#define TPO_R03_EN_PRE_CHARGE   BIT(6)
#define TPO_R03_SOFTWARE_CTL    BIT(7)

#define TPO_R04_NFLIP_H     BIT(0)
#define TPO_R04_NFLIP_V     BIT(1)
#define TPO_R04_CP_CLK_FREQ_1H  BIT(2)
#define TPO_R04_VGL_FREQ_1H BIT(4)

#define TPO_R03_VAL_NORMAL (TPO_R03_NSTANDBY | TPO_R03_EN_CP_CLK | \
            TPO_R03_EN_VGL_PUMP |  TPO_R03_EN_PWM | \
            TPO_R03_DRIVING_CAP_100 | TPO_R03_EN_PRE_CHARGE | \
            TPO_R03_SOFTWARE_CTL)

#define TPO_R03_VAL_STANDBY (TPO_R03_DRIVING_CAP_100 | \
            TPO_R03_EN_PRE_CHARGE | TPO_R03_SOFTWARE_CTL)

static const u16 tpo_td043_def_gamma[12] = {
    105, 315, 381, 431, 490, 537, 579, 686, 780, 837, 880, 1023
};

struct tpo_td043_device {
    struct spi_device *spi;
    struct regulator *vcc_reg;
    int nreset_gpio;
    u16 gamma[12];
    u32 mode;
    u32 hmirror:1;
    u32 vmirror:1;
    u32 powered_on:1;
    u32 spi_suspended:1;
    u32 power_on_resume:1;
};

static int tpo_td043_write(struct spi_device *spi, u8 addr, u8 data)
{
    struct spi_message  m;
    struct spi_transfer xfer;
    u16         w;
    int         r;

    spi_message_init(&m);

    memset(&xfer, 0, sizeof(xfer));

    w = ((u16)addr << 10) | (1 << 8) | data;
    xfer.tx_buf = &w;
    xfer.bits_per_word = 16;
    xfer.len = 2;
    spi_message_add_tail(&xfer, &m);

    r = spi_sync(spi, &m);
    if (r < 0)
        dev_warn(&spi->dev, "failed to write to LCD reg (%d)\n", r);
    return r;
}

static void tpo_td043_write_gamma(struct spi_device *spi, u16 gamma[12])
{
    u8 i, val;

    /* gamma bits [9:8] */
    for (val = i = 0; i < 4; i++)
        val |= (gamma[i] & 0x300) >> ((i + 1) * 2);
    tpo_td043_write(spi, 0x11, val);

    for (val = i = 0; i < 4; i++)
        val |= (gamma[i+4] & 0x300) >> ((i + 1) * 2);
    tpo_td043_write(spi, 0x12, val);

    for (val = i = 0; i < 4; i++)
        val |= (gamma[i+8] & 0x300) >> ((i + 1) * 2);
    tpo_td043_write(spi, 0x13, val);

    /* gamma bits [7:0] */
    for (val = i = 0; i < 12; i++)
        tpo_td043_write(spi, 0x14 + i, gamma[i] & 0xff);
}

static int tpo_td043_write_mirror(struct spi_device *spi, bool h, bool v)
{
    u8 reg4 = TPO_R04_NFLIP_H | TPO_R04_NFLIP_V | \
        TPO_R04_CP_CLK_FREQ_1H | TPO_R04_VGL_FREQ_1H;
    if (h)
        reg4 &= ~TPO_R04_NFLIP_H;
    if (v)
        reg4 &= ~TPO_R04_NFLIP_V;

    return tpo_td043_write(spi, 4, reg4);
}

static int tpo_td043_set_hmirror(struct omap_dss_device *dssdev, bool enable)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(&dssdev->dev);

    tpo_td043->hmirror = enable;
    return tpo_td043_write_mirror(tpo_td043->spi, tpo_td043->hmirror,
            tpo_td043->vmirror);
}

static bool tpo_td043_get_hmirror(struct omap_dss_device *dssdev)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(&dssdev->dev);

    return tpo_td043->hmirror;
}

static ssize_t tpo_td043_vmirror_show(struct device *dev,
    struct device_attribute *attr, char *buf)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(dev);

    return snprintf(buf, PAGE_SIZE, "%d\n", tpo_td043->vmirror);
}

static ssize_t tpo_td043_vmirror_store(struct device *dev,
    struct device_attribute *attr, const char *buf, size_t count)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(dev);
    int val;
    int ret;

    ret = kstrtoint(buf, 0, &val);
    if (ret < 0)
        return ret;

    val = !!val;

    ret = tpo_td043_write_mirror(tpo_td043->spi, tpo_td043->hmirror, val);
    if (ret < 0)
        return ret;

    tpo_td043->vmirror = val;

    return count;
}

static ssize_t tpo_td043_mode_show(struct device *dev,
    struct device_attribute *attr, char *buf)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(dev);

    return snprintf(buf, PAGE_SIZE, "%d\n", tpo_td043->mode);
}

static ssize_t tpo_td043_mode_store(struct device *dev,
    struct device_attribute *attr, const char *buf, size_t count)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(dev);
    long val;
    int ret;

    ret = kstrtol(buf, 0, &val);
    if (ret != 0 || val & ~7)
        return -EINVAL;

    tpo_td043->mode = val;

    val |= TPO_R02_NCLK_RISING;
    tpo_td043_write(tpo_td043->spi, 2, val);

    return count;
}

static ssize_t tpo_td043_gamma_show(struct device *dev,
    struct device_attribute *attr, char *buf)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(dev);
    ssize_t len = 0;
    int ret;
    int i;

    for (i = 0; i < ARRAY_SIZE(tpo_td043->gamma); i++) {
        ret = snprintf(buf + len, PAGE_SIZE - len, "%u ",
                tpo_td043->gamma[i]);
        if (ret < 0)
            return ret;
        len += ret;
    }
    buf[len - 1] = '\n';

    return len;
}

static ssize_t tpo_td043_gamma_store(struct device *dev,
    struct device_attribute *attr, const char *buf, size_t count)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(dev);
    unsigned int g[12];
    int ret;
    int i;

    ret = sscanf(buf, "%u %u %u %u %u %u %u %u %u %u %u %u",
            &g[0], &g[1], &g[2], &g[3], &g[4], &g[5],
            &g[6], &g[7], &g[8], &g[9], &g[10], &g[11]);

    if (ret != 12)
        return -EINVAL;

    for (i = 0; i < 12; i++)
        tpo_td043->gamma[i] = g[i];

    tpo_td043_write_gamma(tpo_td043->spi, tpo_td043->gamma);

    return count;
}

static DEVICE_ATTR(vmirror, S_IRUGO | S_IWUSR,
        tpo_td043_vmirror_show, tpo_td043_vmirror_store);
static DEVICE_ATTR(mode, S_IRUGO | S_IWUSR,
        tpo_td043_mode_show, tpo_td043_mode_store);
static DEVICE_ATTR(gamma, S_IRUGO | S_IWUSR,
        tpo_td043_gamma_show, tpo_td043_gamma_store);

static struct attribute *tpo_td043_attrs[] = {
    &dev_attr_vmirror.attr,
    &dev_attr_mode.attr,
    &dev_attr_gamma.attr,
    NULL,
};

static struct attribute_group tpo_td043_attr_group = {
    .attrs = tpo_td043_attrs,
};

static const struct omap_video_timings tpo_td043_timings = {
    .x_res      = 800,
    .y_res      = 480,

    .pixel_clock    = 36000,

    .hsw        = 1,
    .hfp        = 68,
    .hbp        = 214,

    .vsw        = 1,
    .vfp        = 39,
    .vbp        = 34,

    .vsync_level    = OMAPDSS_SIG_ACTIVE_LOW,
    .hsync_level    = OMAPDSS_SIG_ACTIVE_LOW,
    .data_pclk_edge = OMAPDSS_DRIVE_SIG_FALLING_EDGE,
    .de_level   = OMAPDSS_SIG_ACTIVE_HIGH,
    .sync_pclk_edge = OMAPDSS_DRIVE_SIG_OPPOSITE_EDGES,
};

static int tpo_td043_power_on(struct tpo_td043_device *tpo_td043)
{
    int nreset_gpio = tpo_td043->nreset_gpio;
    int r;

    if (tpo_td043->powered_on)
        return 0;

    r = regulator_enable(tpo_td043->vcc_reg);
    if (r != 0)
        return r;

    /* wait for panel to stabilize */
    msleep(160);

    if (gpio_is_valid(nreset_gpio))
        gpio_set_value(nreset_gpio, 1);

    tpo_td043_write(tpo_td043->spi, 2,
            TPO_R02_MODE(tpo_td043->mode) | TPO_R02_NCLK_RISING);
    tpo_td043_write(tpo_td043->spi, 3, TPO_R03_VAL_NORMAL);
    tpo_td043_write(tpo_td043->spi, 0x20, 0xf0);
    tpo_td043_write(tpo_td043->spi, 0x21, 0xf0);
    tpo_td043_write_mirror(tpo_td043->spi, tpo_td043->hmirror,
            tpo_td043->vmirror);
    tpo_td043_write_gamma(tpo_td043->spi, tpo_td043->gamma);

    tpo_td043->powered_on = 1;
    return 0;
}

static void tpo_td043_power_off(struct tpo_td043_device *tpo_td043)
{
    int nreset_gpio = tpo_td043->nreset_gpio;

    if (!tpo_td043->powered_on)
        return;

    tpo_td043_write(tpo_td043->spi, 3,
            TPO_R03_VAL_STANDBY | TPO_R03_EN_PWM);

    if (gpio_is_valid(nreset_gpio))
        gpio_set_value(nreset_gpio, 0);

    /* wait for at least 2 vsyncs before cutting off power */
    msleep(50);

    tpo_td043_write(tpo_td043->spi, 3, TPO_R03_VAL_STANDBY);

    regulator_disable(tpo_td043->vcc_reg);

    tpo_td043->powered_on = 0;
}

static int tpo_td043_enable_dss(struct omap_dss_device *dssdev)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(&dssdev->dev);
    int r;

    if (dssdev->state == OMAP_DSS_DISPLAY_ACTIVE)
        return 0;

    omapdss_dpi_set_timings(dssdev, &dssdev->panel.timings);
    omapdss_dpi_set_data_lines(dssdev, dssdev->phy.dpi.data_lines);

    r = omapdss_dpi_display_enable(dssdev);
    if (r)
        goto err0;

    if (dssdev->platform_enable) {
        r = dssdev->platform_enable(dssdev);
        if (r)
            goto err1;
    }

    /*
     * If we are resuming from system suspend, SPI clocks might not be
     * enabled yet, so we'll program the LCD from SPI PM resume callback.
     */
    if (!tpo_td043->spi_suspended) {
        r = tpo_td043_power_on(tpo_td043);
        if (r)
            goto err1;
    }

    dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;

    return 0;
err1:
    omapdss_dpi_display_disable(dssdev);
err0:
    return r;
}

static void tpo_td043_disable_dss(struct omap_dss_device *dssdev)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(&dssdev->dev);

    if (dssdev->state != OMAP_DSS_DISPLAY_ACTIVE)
        return;

    if (dssdev->platform_disable)
        dssdev->platform_disable(dssdev);

    omapdss_dpi_display_disable(dssdev);

    if (!tpo_td043->spi_suspended)
        tpo_td043_power_off(tpo_td043);
}

static int tpo_td043_enable(struct omap_dss_device *dssdev)
{
    dev_dbg(&dssdev->dev, "enable\n");

    return tpo_td043_enable_dss(dssdev);
}

static void tpo_td043_disable(struct omap_dss_device *dssdev)
{
    dev_dbg(&dssdev->dev, "disable\n");

    tpo_td043_disable_dss(dssdev);

    dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
}

static int tpo_td043_suspend(struct omap_dss_device *dssdev)
{
    dev_dbg(&dssdev->dev, "suspend\n");

    tpo_td043_disable_dss(dssdev);

    dssdev->state = OMAP_DSS_DISPLAY_SUSPENDED;

    return 0;
}

static int tpo_td043_resume(struct omap_dss_device *dssdev)
{
    dev_dbg(&dssdev->dev, "resume\n");

    return tpo_td043_enable_dss(dssdev);
}

static int tpo_td043_probe(struct omap_dss_device *dssdev)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(&dssdev->dev);
    int nreset_gpio = dssdev->reset_gpio;
    int ret = 0;

    dev_dbg(&dssdev->dev, "probe\n");

    if (tpo_td043 == NULL) {
        dev_err(&dssdev->dev, "missing tpo_td043_device\n");
        return -ENODEV;
    }

    dssdev->panel.timings = tpo_td043_timings;
    dssdev->ctrl.pixel_size = 24;

    tpo_td043->mode = TPO_R02_MODE_800x480;
    memcpy(tpo_td043->gamma, tpo_td043_def_gamma, sizeof(tpo_td043->gamma));

    tpo_td043->vcc_reg = regulator_get(&dssdev->dev, "vcc");
    if (IS_ERR(tpo_td043->vcc_reg)) {
        dev_err(&dssdev->dev, "failed to get LCD VCC regulator\n");
        ret = PTR_ERR(tpo_td043->vcc_reg);
        goto fail_regulator;
    }

    if (gpio_is_valid(nreset_gpio)) {
        ret = gpio_request_one(nreset_gpio, GPIOF_OUT_INIT_LOW,
                    "lcd reset");
        if (ret < 0) {
            dev_err(&dssdev->dev, "couldn't request reset GPIO\n");
            goto fail_gpio_req;
        }
    }

    ret = sysfs_create_group(&dssdev->dev.kobj, &tpo_td043_attr_group);
    if (ret)
        dev_warn(&dssdev->dev, "failed to create sysfs files\n");

    return 0;

fail_gpio_req:
    regulator_put(tpo_td043->vcc_reg);
fail_regulator:
    kfree(tpo_td043);
    return ret;
}

static void tpo_td043_remove(struct omap_dss_device *dssdev)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(&dssdev->dev);
    int nreset_gpio = dssdev->reset_gpio;

    dev_dbg(&dssdev->dev, "remove\n");

    sysfs_remove_group(&dssdev->dev.kobj, &tpo_td043_attr_group);
    regulator_put(tpo_td043->vcc_reg);
    if (gpio_is_valid(nreset_gpio))
        gpio_free(nreset_gpio);
}

static void tpo_td043_set_timings(struct omap_dss_device *dssdev,
        struct omap_video_timings *timings)
{
    omapdss_dpi_set_timings(dssdev, timings);

    dssdev->panel.timings = *timings;
}

static int tpo_td043_check_timings(struct omap_dss_device *dssdev,
        struct omap_video_timings *timings)
{
    return dpi_check_timings(dssdev, timings);
}

static struct omap_dss_driver tpo_td043_driver = {
    .probe      = tpo_td043_probe,
    .remove     = tpo_td043_remove,

    .enable     = tpo_td043_enable,
    .disable    = tpo_td043_disable,
    .suspend    = tpo_td043_suspend,
    .resume     = tpo_td043_resume,
    .set_mirror = tpo_td043_set_hmirror,
    .get_mirror = tpo_td043_get_hmirror,

    .set_timings    = tpo_td043_set_timings,
    .check_timings  = tpo_td043_check_timings,

    .driver         = {
        .name   = "tpo_td043mtea1_panel",
        .owner  = THIS_MODULE,
    },
};

static int tpo_td043_spi_probe(struct spi_device *spi)
{
    struct omap_dss_device *dssdev = spi->dev.platform_data;
    struct tpo_td043_device *tpo_td043;
    int ret;

    if (dssdev == NULL) {
        dev_err(&spi->dev, "missing dssdev\n");
        return -ENODEV;
    }

    spi->bits_per_word = 16;
    spi->mode = SPI_MODE_0;

    ret = spi_setup(spi);
    if (ret < 0) {
        dev_err(&spi->dev, "spi_setup failed: %d\n", ret);
        return ret;
    }

    tpo_td043 = kzalloc(sizeof(*tpo_td043), GFP_KERNEL);
    if (tpo_td043 == NULL)
        return -ENOMEM;

    tpo_td043->spi = spi;
    tpo_td043->nreset_gpio = dssdev->reset_gpio;
    dev_set_drvdata(&spi->dev, tpo_td043);
    dev_set_drvdata(&dssdev->dev, tpo_td043);

    omap_dss_register_driver(&tpo_td043_driver);

    return 0;
}

static int __devexit tpo_td043_spi_remove(struct spi_device *spi)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(&spi->dev);

    omap_dss_unregister_driver(&tpo_td043_driver);
    kfree(tpo_td043);

    return 0;
}

#ifdef CONFIG_PM_SLEEP
static int tpo_td043_spi_suspend(struct device *dev)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(dev);

    dev_dbg(dev, "tpo_td043_spi_suspend, tpo %p\n", tpo_td043);

    tpo_td043->power_on_resume = tpo_td043->powered_on;
    tpo_td043_power_off(tpo_td043);
    tpo_td043->spi_suspended = 1;

    return 0;
}

static int tpo_td043_spi_resume(struct device *dev)
{
    struct tpo_td043_device *tpo_td043 = dev_get_drvdata(dev);
    int ret;

    dev_dbg(dev, "tpo_td043_spi_resume\n");

    if (tpo_td043->power_on_resume) {
        ret = tpo_td043_power_on(tpo_td043);
        if (ret)
            return ret;
    }
    tpo_td043->spi_suspended = 0;

    return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(tpo_td043_spi_pm,
    tpo_td043_spi_suspend, tpo_td043_spi_resume);

static struct spi_driver tpo_td043_spi_driver = {
    .driver = {
        .name   = "tpo_td043mtea1_panel_spi",
        .owner  = THIS_MODULE,
        .pm = &tpo_td043_spi_pm,
    },
    .probe  = tpo_td043_spi_probe,
    .remove = __devexit_p(tpo_td043_spi_remove),
};

module_spi_driver(tpo_td043_spi_driver);

MODULE_AUTHOR("Gražvydas Ignotas <[email protected]>");
MODULE_DESCRIPTION("TPO TD043MTEA1 LCD Driver");
MODULE_LICENSE("GPL");