LXR linux/drivers/video/backlight/jornada720

   1/*
   2 *
   3 * LCD driver for HP Jornada 700 series (710/720/728)
   4 * Copyright (C) 2006-2009 Kristoffer Ericson <kristoffer.ericson@gmail.com>
   5 *
   6 * This program is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public License version
   8 * 2 or any later version as published by the Free Software Foundation.
   9 *
  10 */
  11
  12#include <linux/device.h>
  13#include <linux/fb.h>
  14#include <linux/kernel.h>
  15#include <linux/lcd.h>
  16#include <linux/module.h>
  17#include <linux/platform_device.h>
  18#include <linux/delay.h>
  19
  20#include <mach/jornada720.h>
  21#include <mach/hardware.h>
  22
  23#include <video/s1d13xxxfb.h>
  24
  25#define LCD_MAX_CONTRAST        0xff
  26#define LCD_DEF_CONTRAST        0x80
  27
  28static int jornada_lcd_get_power(struct lcd_device *ld)
  29{
  30        /* LDD2 in PPC = LCD POWER */
  31        if (PPSR & PPC_LDD2)
  32                return FB_BLANK_UNBLANK;        /* PW ON */
  33        else
  34                return FB_BLANK_POWERDOWN;      /* PW OFF */
  35}
  36
  37static int jornada_lcd_get_contrast(struct lcd_device *ld)
  38{
  39        int ret;
  40
  41        if (jornada_lcd_get_power(ld) != FB_BLANK_UNBLANK)
  42                return 0;
  43
  44        jornada_ssp_start();
  45
  46        if (jornada_ssp_byte(GETCONTRAST) != TXDUMMY) {
  47                dev_err(&ld->dev, "get contrast failed\n");
  48                jornada_ssp_end();
  49                return -ETIMEDOUT;
  50        } else {
  51                ret = jornada_ssp_byte(TXDUMMY);
  52                jornada_ssp_end();
  53                return ret;
  54        }
  55}
  56
  57static int jornada_lcd_set_contrast(struct lcd_device *ld, int value)
  58{
  59        int ret;
  60
  61        jornada_ssp_start();
  62
  63        /* start by sending our set contrast cmd to mcu */
  64        ret = jornada_ssp_byte(SETCONTRAST);
  65
  66        /* push the new value */
  67        if (jornada_ssp_byte(value) != TXDUMMY) {
  68                dev_err(&ld->dev, "set contrast failed\n");
  69                jornada_ssp_end();
  70                return -ETIMEDOUT;
  71        }
  72
  73        /* if we get here we can assume everything went well */
  74        jornada_ssp_end();
  75
  76        return 0;
  77}
  78
  79static int jornada_lcd_set_power(struct lcd_device *ld, int power)
  80{
  81        if (power != FB_BLANK_UNBLANK) {
  82                PPSR &= ~PPC_LDD2;
  83                PPDR |= PPC_LDD2;
  84        } else {
  85                PPSR |= PPC_LDD2;
  86        }
  87
  88        return 0;
  89}
  90
  91static struct lcd_ops jornada_lcd_props = {
  92        .get_contrast = jornada_lcd_get_contrast,
  93        .set_contrast = jornada_lcd_set_contrast,
  94        .get_power = jornada_lcd_get_power,
  95        .set_power = jornada_lcd_set_power,
  96};
  97
  98static int jornada_lcd_probe(struct platform_device *pdev)
  99{
 100        struct lcd_device *lcd_device;
 101        int ret;
 102
 103        lcd_device = lcd_device_register(S1D_DEVICENAME, &pdev->dev, NULL, &jornada_lcd_props);
 104
 105        if (IS_ERR(lcd_device)) {
 106                ret = PTR_ERR(lcd_device);
 107                dev_err(&pdev->dev, "failed to register device\n");
 108                return ret;
 109        }
 110
 111        platform_set_drvdata(pdev, lcd_device);
 112
 113        /* lets set our default values */
 114        jornada_lcd_set_contrast(lcd_device, LCD_DEF_CONTRAST);
 115        jornada_lcd_set_power(lcd_device, FB_BLANK_UNBLANK);
 116        /* give it some time to startup */
 117        msleep(100);
 118
 119        return 0;
 120}
 121
 122static int jornada_lcd_remove(struct platform_device *pdev)
 123{
 124        struct lcd_device *lcd_device = platform_get_drvdata(pdev);
 125
 126        lcd_device_unregister(lcd_device);
 127
 128        return 0;
 129}
 130
 131static struct platform_driver jornada_lcd_driver = {
 132        .probe  = jornada_lcd_probe,
 133        .remove = jornada_lcd_remove,
 134        .driver = {
 135                .name   = "jornada_lcd",
 136        },
 137};
 138
 139module_platform_driver(jornada_lcd_driver);
 140
 141MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@gmail.com>");
 142MODULE_DESCRIPTION("HP Jornada 710/720/728 LCD driver");
 143MODULE_LICENSE("GPL");
 144