Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx
[linux-2.6-block.git] / drivers / pci / pci-acpi.c
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1da177e4
LT
1/*
2 * File: pci-acpi.c
a406d9e6 3 * Purpose: Provide PCI support in ACPI
1da177e4 4 *
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5 * Copyright (C) 2005 David Shaohua Li <shaohua.li@intel.com>
6 * Copyright (C) 2004 Tom Long Nguyen <tom.l.nguyen@intel.com>
7 * Copyright (C) 2004 Intel Corp.
1da177e4
LT
8 */
9
10#include <linux/delay.h>
11#include <linux/init.h>
12#include <linux/pci.h>
13#include <linux/module.h>
5fde244d 14#include <linux/pci-aspm.h>
1da177e4 15#include <acpi/acpi.h>
1da177e4
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16#include <acpi/acpi_bus.h>
17
18#include <linux/pci-acpi.h>
0f64474b 19#include "pci.h"
1da177e4 20
0f64474b
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21/*
22 * _SxD returns the D-state with the highest power
23 * (lowest D-state number) supported in the S-state "x".
24 *
25 * If the devices does not have a _PRW
26 * (Power Resources for Wake) supporting system wakeup from "x"
27 * then the OS is free to choose a lower power (higher number
28 * D-state) than the return value from _SxD.
29 *
30 * But if _PRW is enabled at S-state "x", the OS
31 * must not choose a power lower than _SxD --
32 * unless the device has an _SxW method specifying
33 * the lowest power (highest D-state number) the device
34 * may enter while still able to wake the system.
35 *
36 * ie. depending on global OS policy:
37 *
38 * if (_PRW at S-state x)
39 * choose from highest power _SxD to lowest power _SxW
40 * else // no _PRW at S-state x
41 * choose highest power _SxD or any lower power
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42 */
43
8d2bdf49 44static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
0f64474b 45{
ab826ca4 46 int acpi_state;
0f64474b 47
06166780 48 acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL);
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SL
49 if (acpi_state < 0)
50 return PCI_POWER_ERROR;
51
52 switch (acpi_state) {
53 case ACPI_STATE_D0:
54 return PCI_D0;
55 case ACPI_STATE_D1:
56 return PCI_D1;
57 case ACPI_STATE_D2:
58 return PCI_D2;
59 case ACPI_STATE_D3:
60 return PCI_D3hot;
61 }
62 return PCI_POWER_ERROR;
0f64474b 63}
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RW
64
65static bool acpi_pci_power_manageable(struct pci_dev *dev)
66{
67 acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
68
69 return handle ? acpi_bus_power_manageable(handle) : false;
70}
0f64474b 71
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72static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
73{
74 acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
10b3dcae 75 acpi_handle tmp;
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76 static const u8 state_conv[] = {
77 [PCI_D0] = ACPI_STATE_D0,
78 [PCI_D1] = ACPI_STATE_D1,
79 [PCI_D2] = ACPI_STATE_D2,
80 [PCI_D3hot] = ACPI_STATE_D3,
81 [PCI_D3cold] = ACPI_STATE_D3
b913100d 82 };
44e4e66e 83 int error = -EINVAL;
b913100d 84
10b3dcae 85 /* If the ACPI device has _EJ0, ignore the device */
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86 if (!handle || ACPI_SUCCESS(acpi_get_handle(handle, "_EJ0", &tmp)))
87 return -ENODEV;
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88
89 switch (state) {
90 case PCI_D0:
91 case PCI_D1:
92 case PCI_D2:
93 case PCI_D3hot:
94 case PCI_D3cold:
44e4e66e 95 error = acpi_bus_set_power(handle, state_conv[state]);
583c377f 96 }
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97
98 if (!error)
99 dev_printk(KERN_INFO, &dev->dev,
100 "power state changed by ACPI to D%d\n", state);
101
102 return error;
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103}
104
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105static bool acpi_pci_can_wakeup(struct pci_dev *dev)
106{
107 acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
108
109 return handle ? acpi_bus_can_wakeup(handle) : false;
110}
111
112static int acpi_pci_sleep_wake(struct pci_dev *dev, bool enable)
113{
114 int error = acpi_pm_device_sleep_wake(&dev->dev, enable);
115
116 if (!error)
117 dev_printk(KERN_INFO, &dev->dev,
118 "wake-up capability %s by ACPI\n",
119 enable ? "enabled" : "disabled");
120 return error;
121}
122
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123static struct pci_platform_pm_ops acpi_pci_platform_pm = {
124 .is_manageable = acpi_pci_power_manageable,
125 .set_state = acpi_pci_set_power_state,
126 .choose_state = acpi_pci_choose_state,
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127 .can_wakeup = acpi_pci_can_wakeup,
128 .sleep_wake = acpi_pci_sleep_wake,
961d9120 129};
b913100d 130
84df749f 131/* ACPI bus type */
9c273b95 132static int acpi_pci_find_device(struct device *dev, acpi_handle *handle)
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133{
134 struct pci_dev * pci_dev;
135 acpi_integer addr;
136
137 pci_dev = to_pci_dev(dev);
138 /* Please ref to ACPI spec for the syntax of _ADR */
139 addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
140 *handle = acpi_get_child(DEVICE_ACPI_HANDLE(dev->parent), addr);
141 if (!*handle)
142 return -ENODEV;
143 return 0;
144}
145
9c273b95 146static int acpi_pci_find_root_bridge(struct device *dev, acpi_handle *handle)
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147{
148 int num;
149 unsigned int seg, bus;
150
151 /*
152 * The string should be the same as root bridge's name
153 * Please look at 'pci_scan_bus_parented'
154 */
1a927133 155 num = sscanf(dev_name(dev), "pci%04x:%02x", &seg, &bus);
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156 if (num != 2)
157 return -ENODEV;
158 *handle = acpi_get_pci_rootbridge_handle(seg, bus);
159 if (!*handle)
160 return -ENODEV;
161 return 0;
162}
163
9c273b95 164static struct acpi_bus_type acpi_pci_bus = {
84df749f 165 .bus = &pci_bus_type,
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166 .find_device = acpi_pci_find_device,
167 .find_bridge = acpi_pci_find_root_bridge,
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168};
169
9c273b95 170static int __init acpi_pci_init(void)
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171{
172 int ret;
173
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174 if (acpi_gbl_FADT.boot_flags & BAF_MSI_NOT_SUPPORTED) {
175 printk(KERN_INFO"ACPI FADT declares the system doesn't support MSI, so disable it\n");
176 pci_no_msi();
177 }
5fde244d
SL
178
179 if (acpi_gbl_FADT.boot_flags & BAF_PCIE_ASPM_CONTROL) {
180 printk(KERN_INFO"ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
181 pcie_no_aspm();
182 }
183
9c273b95 184 ret = register_acpi_bus_type(&acpi_pci_bus);
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185 if (ret)
186 return 0;
961d9120 187 pci_set_platform_pm(&acpi_pci_platform_pm);
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188 return 0;
189}
9c273b95 190arch_initcall(acpi_pci_init);