arch/x86/platform/olpc/olpc-xo1-pm.c

   1 /*
   2  * Support for power management features of the OLPC XO-1 laptop
   3  *
   4  * Copyright (C) 2010 Andres Salomon <dilinger@queued.net>
   5  * Copyright (C) 2010 One Laptop per Child
   6  * Copyright (C) 2006 Red Hat, Inc.
   7  * Copyright (C) 2006 Advanced Micro Devices, Inc.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  */
  14
  15 #include <linux/cs5535.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/export.h>
  18 #include <linux/pm.h>
  19 #include <linux/mfd/core.h>
  20 #include <linux/suspend.h>
  21
  22 #include <asm/io.h>
  23 #include <asm/olpc.h>
  24
  25 #define DRV_NAME "olpc-xo1-pm"
  26
  27 static unsigned long acpi_base;
  28 static unsigned long pms_base;
  29
  30 static u16 wakeup_mask = CS5536_PM_PWRBTN;
  31
  32 static struct {
  33         unsigned long address;
  34         unsigned short segment;
  35 } ofw_bios_entry = { 0xF0000 + PAGE_OFFSET, __KERNEL_CS };
  36
  37 /* Set bits in the wakeup mask */
  38 void olpc_xo1_pm_wakeup_set(u16 value)
  39 {
  40         wakeup_mask |= value;
  41 }
  42 EXPORT_SYMBOL_GPL(olpc_xo1_pm_wakeup_set);
  43
  44 /* Clear bits in the wakeup mask */
  45 void olpc_xo1_pm_wakeup_clear(u16 value)
  46 {
  47         wakeup_mask &= ~value;
  48 }
  49 EXPORT_SYMBOL_GPL(olpc_xo1_pm_wakeup_clear);
  50
  51 static int xo1_power_state_enter(suspend_state_t pm_state)
  52 {
  53         unsigned long saved_sci_mask;
  54         int r;
  55
  56         /* Only STR is supported */
  57         if (pm_state != PM_SUSPEND_MEM)
  58                 return -EINVAL;
  59
  60         r = olpc_ec_cmd(EC_SET_SCI_INHIBIT, NULL, 0, NULL, 0);
  61         if (r)
  62                 return r;
  63
  64         /*
  65          * Save SCI mask (this gets lost since PM1_EN is used as a mask for
  66          * wakeup events, which is not necessarily the same event set)
  67          */
  68         saved_sci_mask = inl(acpi_base + CS5536_PM1_STS);
  69         saved_sci_mask &= 0xffff0000;
  70
  71         /* Save CPU state */
  72         do_olpc_suspend_lowlevel();
  73
  74         /* Resume path starts here */
  75
  76         /* Restore SCI mask (using dword access to CS5536_PM1_EN) */
  77         outl(saved_sci_mask, acpi_base + CS5536_PM1_STS);
  78
  79         /* Tell the EC to stop inhibiting SCIs */
  80         olpc_ec_cmd(EC_SET_SCI_INHIBIT_RELEASE, NULL, 0, NULL, 0);
  81
  82         /*
  83          * Tell the wireless module to restart USB communication.
  84          * Must be done twice.
  85          */
  86         olpc_ec_cmd(EC_WAKE_UP_WLAN, NULL, 0, NULL, 0);
  87         olpc_ec_cmd(EC_WAKE_UP_WLAN, NULL, 0, NULL, 0);
  88
  89         return 0;
  90 }
  91
  92 asmlinkage int xo1_do_sleep(u8 sleep_state)
  93 {
  94         void *pgd_addr = __va(read_cr3());
  95
  96         /* Program wakeup mask (using dword access to CS5536_PM1_EN) */
  97         outl(wakeup_mask << 16, acpi_base + CS5536_PM1_STS);
  98
  99         __asm__("movl %0,%%eax" : : "r" (pgd_addr));
 100         __asm__("call *(%%edi); cld"
 101                 : : "D" (&ofw_bios_entry));
 102         __asm__("movb $0x34, %al\n\t"
 103                 "outb %al, $0x70\n\t"
 104                 "movb $0x30, %al\n\t"
 105                 "outb %al, $0x71\n\t");
 106         return 0;
 107 }
 108
 109 static void xo1_power_off(void)
 110 {
 111         printk(KERN_INFO "OLPC XO-1 power off sequence...\n");
 112
 113         /* Enable all of these controls with 0 delay */
 114         outl(0x40000000, pms_base + CS5536_PM_SCLK);
 115         outl(0x40000000, pms_base + CS5536_PM_IN_SLPCTL);
 116         outl(0x40000000, pms_base + CS5536_PM_WKXD);
 117         outl(0x40000000, pms_base + CS5536_PM_WKD);
 118
 119         /* Clear status bits (possibly unnecessary) */
 120         outl(0x0002ffff, pms_base  + CS5536_PM_SSC);
 121         outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS);
 122
 123         /* Write SLP_EN bit to start the machinery */
 124         outl(0x00002000, acpi_base + CS5536_PM1_CNT);
 125 }
 126
 127 static int xo1_power_state_valid(suspend_state_t pm_state)
 128 {
 129         /* suspend-to-RAM only */
 130         return pm_state == PM_SUSPEND_MEM;
 131 }
 132
 133 static const struct platform_suspend_ops xo1_suspend_ops = {
 134         .valid = xo1_power_state_valid,
 135         .enter = xo1_power_state_enter,
 136 };
 137
 138 static int __devinit xo1_pm_probe(struct platform_device *pdev)
 139 {
 140         struct resource *res;
 141         int err;
 142
 143         /* don't run on non-XOs */
 144         if (!machine_is_olpc())
 145                 return -ENODEV;
 146
 147         err = mfd_cell_enable(pdev);
 148         if (err)
 149                 return err;
 150
 151         res = platform_get_resource(pdev, IORESOURCE_IO, 0);
 152         if (!res) {
 153                 dev_err(&pdev->dev, "can't fetch device resource info\n");
 154                 return -EIO;
 155         }
 156         if (strcmp(pdev->name, "cs5535-pms") == 0)
 157                 pms_base = res->start;
 158         else if (strcmp(pdev->name, "olpc-xo1-pm-acpi") == 0)
 159                 acpi_base = res->start;
 160
 161         /* If we have both addresses, we can override the poweroff hook */
 162         if (pms_base && acpi_base) {
 163                 suspend_set_ops(&xo1_suspend_ops);
 164                 pm_power_off = xo1_power_off;
 165                 printk(KERN_INFO "OLPC XO-1 support registered\n");
 166         }
 167
 168         return 0;
 169 }
 170
 171 static int __devexit xo1_pm_remove(struct platform_device *pdev)
 172 {
 173         mfd_cell_disable(pdev);
 174
 175         if (strcmp(pdev->name, "cs5535-pms") == 0)
 176                 pms_base = 0;
 177         else if (strcmp(pdev->name, "olpc-xo1-pm-acpi") == 0)
 178                 acpi_base = 0;
 179
 180         pm_power_off = NULL;
 181         return 0;
 182 }
 183
 184 static struct platform_driver cs5535_pms_driver = {
 185         .driver = {
 186                 .name = "cs5535-pms",
 187                 .owner = THIS_MODULE,
 188         },
 189         .probe = xo1_pm_probe,
 190         .remove = __devexit_p(xo1_pm_remove),
 191 };
 192
 193 static struct platform_driver cs5535_acpi_driver = {
 194         .driver = {
 195                 .name = "olpc-xo1-pm-acpi",
 196                 .owner = THIS_MODULE,
 197         },
 198         .probe = xo1_pm_probe,
 199         .remove = __devexit_p(xo1_pm_remove),
 200 };
 201
 202 static int __init xo1_pm_init(void)
 203 {
 204         int r;
 205
 206         r = platform_driver_register(&cs5535_pms_driver);
 207         if (r)
 208                 return r;
 209
 210         r = platform_driver_register(&cs5535_acpi_driver);
 211         if (r)
 212                 platform_driver_unregister(&cs5535_pms_driver);
 213
 214         return r;
 215 }
 216 arch_initcall(xo1_pm_init);