target/linux/xburst/files-2.6.32/arch/mips/jz4740/pm.c

   1 /*
   2  *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
   3  *      JZ4740 SoC power management support
   4  *
   5  *  This program is free software; you can redistribute  it and/or modify it
   6  *  under  the terms of  the GNU General  Public License as published by the
   7  *  Free Software Foundation;  either version 2 of the  License, or (at your
   8  *  option) any later version.
   9  *
  10  *  You should have received a copy of the  GNU General Public License along
  11  *  with this program; if not, write  to the Free Software Foundation, Inc.,
  12  *  675 Mass Ave, Cambridge, MA 02139, USA.
  13  *
  14  */
  15
  16 #include <linux/init.h>
  17 #include <linux/pm.h>
  18 #include <linux/delay.h>
  19 #include <linux/suspend.h>
  20 #include <asm/mach-jz4740/regs.h>
  21
  22 extern void jz4740_intc_suspend(void);
  23 extern void jz4740_intc_resume(void);
  24
  25 static int jz_pm_enter(suspend_state_t state)
  26 {
  27         unsigned long nfcsr = REG_EMC_NFCSR;
  28         uint32_t scr = REG_CPM_SCR;
  29
  30         /* Disable nand flash */
  31         REG_EMC_NFCSR = ~0xff;
  32
  33         udelay(100);
  34
  35         /*stop udc and usb*/
  36         REG_CPM_SCR &= ~( 1<<6 | 1<<7);
  37         REG_CPM_SCR |= 0<<6 | 1<<7;
  38
  39         jz4740_intc_suspend();
  40
  41         /* Enter SLEEP mode */
  42         REG_CPM_LCR &= ~CPM_LCR_LPM_MASK;
  43         REG_CPM_LCR |= CPM_LCR_LPM_SLEEP;
  44         __asm__(".set\tmips3\n\t"
  45                 "wait\n\t"
  46                 ".set\tmips0");
  47
  48         /* Restore to IDLE mode */
  49         REG_CPM_LCR &= ~CPM_LCR_LPM_MASK;
  50         REG_CPM_LCR |= CPM_LCR_LPM_IDLE;
  51
  52         /* Restore nand flash control register */
  53         REG_EMC_NFCSR = nfcsr;
  54
  55         jz4740_intc_resume();
  56
  57         /* Restore sleep control register */
  58         REG_CPM_SCR = scr;
  59
  60         return 0;
  61 }
  62
  63 static struct platform_suspend_ops jz_pm_ops = {
  64         .valid          = suspend_valid_only_mem,
  65         .enter          = jz_pm_enter,
  66 };
  67
  68 /*
  69  * Initialize power interface
  70  */
  71 int __init jz_pm_init(void)
  72 {
  73         suspend_set_ops(&jz_pm_ops);
  74         return 0;
  75
  76 }
  77 late_initcall(jz_pm_init);