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

   1 /*
   2  * Support for 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/module.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/pm.h>
  18 #include <linux/mfd/core.h>
  19
  20 #include <asm/io.h>
  21 #include <asm/olpc.h>
  22
  23 #define DRV_NAME "olpc-xo1"
  24
  25 /* PMC registers (PMS block) */
  26 #define PM_SCLK         0x10
  27 #define PM_IN_SLPCTL    0x20
  28 #define PM_WKXD         0x34
  29 #define PM_WKD          0x30
  30 #define PM_SSC          0x54
  31
  32 /* PM registers (ACPI block) */
  33 #define PM1_CNT         0x08
  34 #define PM_GPE0_STS     0x18
  35
  36 static unsigned long acpi_base;
  37 static unsigned long pms_base;
  38
  39 static void xo1_power_off(void)
  40 {
  41         printk(KERN_INFO "OLPC XO-1 power off sequence...\n");
  42
  43         /* Enable all of these controls with 0 delay */
  44         outl(0x40000000, pms_base + PM_SCLK);
  45         outl(0x40000000, pms_base + PM_IN_SLPCTL);
  46         outl(0x40000000, pms_base + PM_WKXD);
  47         outl(0x40000000, pms_base + PM_WKD);
  48
  49         /* Clear status bits (possibly unnecessary) */
  50         outl(0x0002ffff, pms_base  + PM_SSC);
  51         outl(0xffffffff, acpi_base + PM_GPE0_STS);
  52
  53         /* Write SLP_EN bit to start the machinery */
  54         outl(0x00002000, acpi_base + PM1_CNT);
  55 }
  56
  57 static int __devinit olpc_xo1_probe(struct platform_device *pdev)
  58 {
  59         struct resource *res;
  60         int err;
  61
  62         /* don't run on non-XOs */
  63         if (!machine_is_olpc())
  64                 return -ENODEV;
  65
  66         err = mfd_cell_enable(pdev);
  67         if (err)
  68                 return err;
  69
  70         res = platform_get_resource(pdev, IORESOURCE_IO, 0);
  71         if (!res) {
  72                 dev_err(&pdev->dev, "can't fetch device resource info\n");
  73                 return -EIO;
  74         }
  75         if (strcmp(pdev->name, "cs5535-pms") == 0)
  76                 pms_base = res->start;
  77         else if (strcmp(pdev->name, "olpc-xo1-pm-acpi") == 0)
  78                 acpi_base = res->start;
  79
  80         /* If we have both addresses, we can override the poweroff hook */
  81         if (pms_base && acpi_base) {
  82                 pm_power_off = xo1_power_off;
  83                 printk(KERN_INFO "OLPC XO-1 support registered\n");
  84         }
  85
  86         return 0;
  87 }
  88
  89 static int __devexit olpc_xo1_remove(struct platform_device *pdev)
  90 {
  91         mfd_cell_disable(pdev);
  92
  93         if (strcmp(pdev->name, "cs5535-pms") == 0)
  94                 pms_base = 0;
  95         else if (strcmp(pdev->name, "olpc-xo1-pm-acpi") == 0)
  96                 acpi_base = 0;
  97
  98         pm_power_off = NULL;
  99         return 0;
 100 }
 101
 102 static struct platform_driver cs5535_pms_drv = {
 103         .driver = {
 104                 .name = "cs5535-pms",
 105                 .owner = THIS_MODULE,
 106         },
 107         .probe = olpc_xo1_probe,
 108         .remove = __devexit_p(olpc_xo1_remove),
 109 };
 110
 111 static struct platform_driver cs5535_acpi_drv = {
 112         .driver = {
 113                 .name = "olpc-xo1-pm-acpi",
 114                 .owner = THIS_MODULE,
 115         },
 116         .probe = olpc_xo1_probe,
 117         .remove = __devexit_p(olpc_xo1_remove),
 118 };
 119
 120 static int __init olpc_xo1_init(void)
 121 {
 122         int r;
 123
 124         r = platform_driver_register(&cs5535_pms_drv);
 125         if (r)
 126                 return r;
 127
 128         r = platform_driver_register(&cs5535_acpi_drv);
 129         if (r)
 130                 platform_driver_unregister(&cs5535_pms_drv);
 131
 132         return r;
 133 }
 134
 135 static void __exit olpc_xo1_exit(void)
 136 {
 137         platform_driver_unregister(&cs5535_acpi_drv);
 138         platform_driver_unregister(&cs5535_pms_drv);
 139 }
 140
 141 MODULE_AUTHOR("Daniel Drake <dsd@laptop.org>");
 142 MODULE_LICENSE("GPL");
 143 MODULE_ALIAS("platform:cs5535-pms");
 144
 145 module_init(olpc_xo1_init);
 146 module_exit(olpc_xo1_exit);