LXR linux/arch/arm/mach-pxa/mfp-pxa3xx.c

   1/*
   2 * linux/arch/arm/mach-pxa/mfp.c
   3 *
   4 * PXA3xx Multi-Function Pin Support
   5 *
   6 * Copyright (C) 2007 Marvell Internation Ltd.
   7 *
   8 * 2007-08-21: eric miao <eric.miao@marvell.com>
   9 *             initial version
  10 *
  11 *  This program is free software; you can redistribute it and/or modify
  12 *  it under the terms of the GNU General Public License version 2 as
  13 *  published by the Free Software Foundation.
  14 */
  15
  16#include <linux/module.h>
  17#include <linux/kernel.h>
  18#include <linux/init.h>
  19#include <linux/io.h>
  20#include <linux/sysdev.h>
  21
  22#include <mach/hardware.h>
  23#include <mach/mfp-pxa3xx.h>
  24#include <mach/pxa3xx-regs.h>
  25
  26#ifdef CONFIG_PM
  27/*
  28 * Configure the MFPs appropriately for suspend/resume.
  29 * FIXME: this should probably depend on which system state we're
  30 * entering - for instance, we might not want to place MFP pins in
  31 * a pull-down mode if they're an active low chip select, and we're
  32 * just entering standby.
  33 */
  34static int pxa3xx_mfp_suspend(struct sys_device *d, pm_message_t state)
  35{
  36        mfp_config_lpm();
  37        return 0;
  38}
  39
  40static int pxa3xx_mfp_resume(struct sys_device *d)
  41{
  42        mfp_config_run();
  43
  44        /* clear RDH bit when MFP settings are restored
  45         *
  46         * NOTE: the last 3 bits DxS are write-1-to-clear so carefully
  47         * preserve them here in case they will be referenced later
  48         */
  49        ASCR &= ~(ASCR_RDH | ASCR_D1S | ASCR_D2S | ASCR_D3S);
  50        return 0;
  51}
  52#else
  53#define pxa3xx_mfp_suspend      NULL
  54#define pxa3xx_mfp_resume       NULL
  55#endif
  56
  57struct sysdev_class pxa3xx_mfp_sysclass = {
  58        .name           = "mfp",
  59        .suspend        = pxa3xx_mfp_suspend,
  60        .resume         = pxa3xx_mfp_resume,
  61};
  62
  63static int __init mfp_init_devicefs(void)
  64{
  65        if (cpu_is_pxa3xx())
  66                return sysdev_class_register(&pxa3xx_mfp_sysclass);
  67
  68        return 0;
  69}
  70postcore_initcall(mfp_init_devicefs);
  71