jornada720_lcd.c

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/*
 *
 * LCD driver for HP Jornada 700 series (710/720/728)
 * Copyright (C) 2006-2009 Kristoffer Ericson <[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 or any later version as published by the Free Software Foundation.
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/device.h>
#include <linux/fb.h>
#include <linux/kernel.h>
#include <linux/lcd.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/delay.h>

#include <mach/jornada720.h>
#include <mach/hardware.h>

#include <video/s1d13xxxfb.h>

#define LCD_MAX_CONTRAST    0xff
#define LCD_DEF_CONTRAST    0x80

static int jornada_lcd_get_power(struct lcd_device *dev)
{
    /* LDD2 in PPC = LCD POWER */
    if (PPSR & PPC_LDD2)
        return FB_BLANK_UNBLANK;    /* PW ON */
    else
        return FB_BLANK_POWERDOWN;  /* PW OFF */
}

static int jornada_lcd_get_contrast(struct lcd_device *dev)
{
    int ret;

    if (jornada_lcd_get_power(dev) != FB_BLANK_UNBLANK)
        return 0;

    jornada_ssp_start();

    if (jornada_ssp_byte(GETCONTRAST) != TXDUMMY) {
        pr_err("get contrast failed\n");
        jornada_ssp_end();
        return -ETIMEDOUT;
    } else {
        ret = jornada_ssp_byte(TXDUMMY);
        jornada_ssp_end();
        return ret;
    }
}

static int jornada_lcd_set_contrast(struct lcd_device *dev, int value)
{
    int ret;

    jornada_ssp_start();

    /* start by sending our set contrast cmd to mcu */
    ret = jornada_ssp_byte(SETCONTRAST);

    /* push the new value */
    if (jornada_ssp_byte(value) != TXDUMMY) {
        pr_err("set contrast failed\n");
        jornada_ssp_end();
        return -ETIMEDOUT;
    }

    /* if we get here we can assume everything went well */
    jornada_ssp_end();

    return 0;
}

static int jornada_lcd_set_power(struct lcd_device *dev, int power)
{
    if (power != FB_BLANK_UNBLANK) {
        PPSR &= ~PPC_LDD2;
        PPDR |= PPC_LDD2;
    } else
        PPSR |= PPC_LDD2;

    return 0;
}

static struct lcd_ops jornada_lcd_props = {
    .get_contrast = jornada_lcd_get_contrast,
    .set_contrast = jornada_lcd_set_contrast,
    .get_power = jornada_lcd_get_power,
    .set_power = jornada_lcd_set_power,
};

static int jornada_lcd_probe(struct platform_device *pdev)
{
    struct lcd_device *lcd_device;
    int ret;

    lcd_device = lcd_device_register(S1D_DEVICENAME, &pdev->dev, NULL, &jornada_lcd_props);

    if (IS_ERR(lcd_device)) {
        ret = PTR_ERR(lcd_device);
        pr_err("failed to register device\n");
        return ret;
    }

    platform_set_drvdata(pdev, lcd_device);

    /* lets set our default values */
    jornada_lcd_set_contrast(lcd_device, LCD_DEF_CONTRAST);
    jornada_lcd_set_power(lcd_device, FB_BLANK_UNBLANK);
    /* give it some time to startup */
    msleep(100);

    return 0;
}

static int jornada_lcd_remove(struct platform_device *pdev)
{
    struct lcd_device *lcd_device = platform_get_drvdata(pdev);

    lcd_device_unregister(lcd_device);

    return 0;
}

static struct platform_driver jornada_lcd_driver = {
    .probe  = jornada_lcd_probe,
    .remove = jornada_lcd_remove,
    .driver = {
        .name   = "jornada_lcd",
    },
};

module_platform_driver(jornada_lcd_driver);

MODULE_AUTHOR("Kristoffer Ericson <[email protected]>");
MODULE_DESCRIPTION("HP Jornada 710/720/728 LCD driver");
MODULE_LICENSE("GPL");