drivers/video/backlight/jornada720_lcd.c

   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
  28 static int jornada_lcd_get_power(struct lcd_device *ld)
  29 {
  30         return PPSR & PPC_LDD2 ? FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN;
  31 }
  32
  33 static int jornada_lcd_get_contrast(struct lcd_device *ld)
  34 {
  35         int ret;
  36
  37         if (jornada_lcd_get_power(ld) != FB_BLANK_UNBLANK)
  38                 return 0;
  39
  40         jornada_ssp_start();
  41
  42         if (jornada_ssp_byte(GETCONTRAST) == TXDUMMY) {
  43                 ret = jornada_ssp_byte(TXDUMMY);
  44                 goto success;
  45         }
  46
  47         dev_err(&ld->dev, "failed to set contrast\n");
  48         ret = -ETIMEDOUT;
  49
  50 success:
  51         jornada_ssp_end();
  52         return ret;
  53 }
  54
  55 static int jornada_lcd_set_contrast(struct lcd_device *ld, int value)
  56 {
  57         int ret = 0;
  58
  59         jornada_ssp_start();
  60
  61         /* start by sending our set contrast cmd to mcu */
  62         if (jornada_ssp_byte(SETCONTRAST) == TXDUMMY) {
  63                 /* if successful push the new value */
  64                 if (jornada_ssp_byte(value) == TXDUMMY)
  65                         goto success;
  66         }
  67
  68         dev_err(&ld->dev, "failed to set contrast\n");
  69         ret = -ETIMEDOUT;
  70
  71 success:
  72         jornada_ssp_end();
  73         return ret;
  74 }
  75
  76 static int jornada_lcd_set_power(struct lcd_device *ld, int power)
  77 {
  78         if (power != FB_BLANK_UNBLANK) {
  79                 PPSR &= ~PPC_LDD2;
  80                 PPDR |= PPC_LDD2;
  81         } else {
  82                 PPSR |= PPC_LDD2;
  83         }
  84
  85         return 0;
  86 }
  87
  88 static struct lcd_ops jornada_lcd_props = {
  89         .get_contrast = jornada_lcd_get_contrast,
  90         .set_contrast = jornada_lcd_set_contrast,
  91         .get_power = jornada_lcd_get_power,
  92         .set_power = jornada_lcd_set_power,
  93 };
  94
  95 static int jornada_lcd_probe(struct platform_device *pdev)
  96 {
  97         struct lcd_device *lcd_device;
  98         int ret;
  99
 100         lcd_device = devm_lcd_device_register(&pdev->dev, S1D_DEVICENAME,
 101                                         &pdev->dev, NULL, &jornada_lcd_props);
 102
 103         if (IS_ERR(lcd_device)) {
 104                 ret = PTR_ERR(lcd_device);
 105                 dev_err(&pdev->dev, "failed to register device\n");
 106                 return ret;
 107         }
 108
 109         platform_set_drvdata(pdev, lcd_device);
 110
 111         /* lets set our default values */
 112         jornada_lcd_set_contrast(lcd_device, LCD_DEF_CONTRAST);
 113         jornada_lcd_set_power(lcd_device, FB_BLANK_UNBLANK);
 114         /* give it some time to startup */
 115         msleep(100);
 116
 117         return 0;
 118 }
 119
 120 static struct platform_driver jornada_lcd_driver = {
 121         .probe  = jornada_lcd_probe,
 122         .driver = {
 123                 .name   = "jornada_lcd",
 124         },
 125 };
 126
 127 module_platform_driver(jornada_lcd_driver);
 128
 129 MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@gmail.com>");
 130 MODULE_DESCRIPTION("HP Jornada 710/720/728 LCD driver");
 131 MODULE_LICENSE("GPL");