arch/arm/common/sharpsl_param.c

   1 /*
   2  * Hardware parameter area specific to Sharp SL series devices
   3  *
   4  * Copyright (c) 2005 Richard Purdie
   5  *
   6  * Based on Sharp's 2.4 kernel patches
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  *
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/string.h>
  16 #include <asm/mach/sharpsl_param.h>
  17
  18 /*
  19  * Certain hardware parameters determined at the time of device manufacture,
  20  * typically including LCD parameters are loaded by the bootloader at the
  21  * address PARAM_BASE. As the kernel will overwrite them, we need to store
  22  * them early in the boot process, then pass them to the appropriate drivers.
  23  * Not all devices use all paramaters but the format is common to all.
  24  */
  25 #ifdef ARCH_SA1100
  26 #define PARAM_BASE      0xe8ffc000
  27 #else
  28 #define PARAM_BASE      0xa0000a00
  29 #endif
  30 #define MAGIC_CHG(a,b,c,d) ( ( d << 24 ) | ( c << 16 )  | ( b << 8 ) | a )
  31
  32 #define COMADJ_MAGIC    MAGIC_CHG('C','M','A','D')
  33 #define UUID_MAGIC      MAGIC_CHG('U','U','I','D')
  34 #define TOUCH_MAGIC     MAGIC_CHG('T','U','C','H')
  35 #define AD_MAGIC        MAGIC_CHG('B','V','A','D')
  36 #define PHAD_MAGIC      MAGIC_CHG('P','H','A','D')
  37
  38 struct sharpsl_param_info sharpsl_param;
  39
  40 void sharpsl_save_param(void)
  41 {
  42         memcpy(&sharpsl_param, (void *)PARAM_BASE, sizeof(struct sharpsl_param_info));
  43
  44         if (sharpsl_param.comadj_keyword != COMADJ_MAGIC)
  45                 sharpsl_param.comadj=-1;
  46
  47         if (sharpsl_param.phad_keyword != PHAD_MAGIC)
  48                 sharpsl_param.phadadj=-1;
  49
  50         if (sharpsl_param.uuid_keyword != UUID_MAGIC)
  51                 sharpsl_param.uuid[0]=-1;
  52
  53         if (sharpsl_param.touch_keyword != TOUCH_MAGIC)
  54                 sharpsl_param.touch_xp=-1;
  55
  56         if (sharpsl_param.adadj_keyword != AD_MAGIC)
  57                 sharpsl_param.adadj=-1;
  58 }
  59
  60