aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/kernel/olpc-xo1.c
blob: f5442c03abc34dd47b58e4742df180516aa6a7be (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
/*
 * Support for features of the OLPC XO-1 laptop
 *
 * Copyright (C) 2010 One Laptop per Child
 * Copyright (C) 2006 Red Hat, Inc.
 * Copyright (C) 2006 Advanced Micro Devices, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/pci.h>
#include <linux/pci_ids.h>
#include <linux/platform_device.h>
#include <linux/pm.h>

#include <asm/io.h>
#include <asm/olpc.h>

#define DRV_NAME "olpc-xo1"

#define PMS_BAR		4
#define ACPI_BAR	5

/* PMC registers (PMS block) */
#define PM_SCLK		0x10
#define PM_IN_SLPCTL	0x20
#define PM_WKXD		0x34
#define PM_WKD		0x30
#define PM_SSC		0x54

/* PM registers (ACPI block) */
#define PM1_CNT		0x08
#define PM_GPE0_STS	0x18

static unsigned long acpi_base;
static unsigned long pms_base;

static void xo1_power_off(void)
{
	printk(KERN_INFO "OLPC XO-1 power off sequence...\n");

	/* Enable all of these controls with 0 delay */
	outl(0x40000000, pms_base + PM_SCLK);
	outl(0x40000000, pms_base + PM_IN_SLPCTL);
	outl(0x40000000, pms_base + PM_WKXD);
	outl(0x40000000, pms_base + PM_WKD);

	/* Clear status bits (possibly unnecessary) */
	outl(0x0002ffff, pms_base  + PM_SSC);
	outl(0xffffffff, acpi_base + PM_GPE0_STS);

	/* Write SLP_EN bit to start the machinery */
	outl(0x00002000, acpi_base + PM1_CNT);
}

/* Read the base addresses from the PCI BAR info */
static int __devinit setup_bases(struct pci_dev *pdev)
{
	int r;

	r = pci_enable_device_io(pdev);
	if (r) {
		dev_err(&pdev->dev, "can't enable device IO\n");
		return r;
	}

	r = pci_request_region(pdev, ACPI_BAR, DRV_NAME);
	if (r) {
		dev_err(&pdev->dev, "can't alloc PCI BAR #%d\n", ACPI_BAR);
		return r;
	}

	r = pci_request_region(pdev, PMS_BAR, DRV_NAME);
	if (r) {
		dev_err(&pdev->dev, "can't alloc PCI BAR #%d\n", PMS_BAR);
		pci_release_region(pdev, ACPI_BAR);
		return r;
	}

	acpi_base = pci_resource_start(pdev, ACPI_BAR);
	pms_base = pci_resource_start(pdev, PMS_BAR);

	return 0;
}

static int __devinit olpc_xo1_probe(struct platform_device *pdev)
{
	struct pci_dev *pcidev;
	int r;

	pcidev = pci_get_device(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA,
				NULL);
	if (!pdev)
		return -ENODEV;

	r = setup_bases(pcidev);
	if (r)
		return r;

	pm_power_off = xo1_power_off;

	printk(KERN_INFO "OLPC XO-1 support registered\n");
	return 0;
}

static int __devexit olpc_xo1_remove(struct platform_device *pdev)
{
	pm_power_off = NULL;
	return 0;
}

static struct platform_driver olpc_xo1_driver = {
	.driver = {
		.name = DRV_NAME,
		.owner = THIS_MODULE,
	},
	.probe = olpc_xo1_probe,
	.remove = __devexit_p(olpc_xo1_remove),
};

static int __init olpc_xo1_init(void)
{
	return platform_driver_register(&olpc_xo1_driver);
}

static void __exit olpc_xo1_exit(void)
{
	platform_driver_unregister(&olpc_xo1_driver);
}

MODULE_AUTHOR("Daniel Drake <dsd@laptop.org>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:olpc-xo1");

module_init(olpc_xo1_init);
module_exit(olpc_xo1_exit);