diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-02-07 13:46:30 -0500 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-02-07 13:46:30 -0500 |
commit | e83102cab0fd95d4508361b061146c978b3abd60 (patch) | |
tree | d1452292bf5d55da6a072d36d507d2e918ee2180 /Documentation | |
parent | 7f9a50a5b89b87f8e754f59ae9968da28be618a5 (diff) | |
parent | 5294e256717923f4a3297bb8b802f5e0625763f3 (diff) |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI PM: make the PM core more careful with drivers using the new PM framework
PCI PM: Read power state from device after trying to change it on resume
PCI PM: Do not disable and enable bridges during suspend-resume
PCI: PCIe portdrv: Simplify suspend and resume
PCI PM: Fix saving of device state in pci_legacy_suspend
PCI PM: Check if the state has been saved before trying to restore it
PCI PM: Fix handling of devices without drivers
PCI: return error on failure to read PCI ROMs
PCI: properly clean up ASPM link state on device remove
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/filesystems/sysfs-pci.txt | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/Documentation/filesystems/sysfs-pci.txt b/Documentation/filesystems/sysfs-pci.txt index 68ef48839c04..9f8740ca3f3b 100644 --- a/Documentation/filesystems/sysfs-pci.txt +++ b/Documentation/filesystems/sysfs-pci.txt | |||
@@ -9,6 +9,7 @@ that support it. For example, a given bus might look like this: | |||
9 | | |-- class | 9 | | |-- class |
10 | | |-- config | 10 | | |-- config |
11 | | |-- device | 11 | | |-- device |
12 | | |-- enable | ||
12 | | |-- irq | 13 | | |-- irq |
13 | | |-- local_cpus | 14 | | |-- local_cpus |
14 | | |-- resource | 15 | | |-- resource |
@@ -32,6 +33,7 @@ files, each with their own function. | |||
32 | class PCI class (ascii, ro) | 33 | class PCI class (ascii, ro) |
33 | config PCI config space (binary, rw) | 34 | config PCI config space (binary, rw) |
34 | device PCI device (ascii, ro) | 35 | device PCI device (ascii, ro) |
36 | enable Whether the device is enabled (ascii, rw) | ||
35 | irq IRQ number (ascii, ro) | 37 | irq IRQ number (ascii, ro) |
36 | local_cpus nearby CPU mask (cpumask, ro) | 38 | local_cpus nearby CPU mask (cpumask, ro) |
37 | resource PCI resource host addresses (ascii, ro) | 39 | resource PCI resource host addresses (ascii, ro) |
@@ -57,10 +59,19 @@ used to do actual device programming from userspace. Note that some platforms | |||
57 | don't support mmapping of certain resources, so be sure to check the return | 59 | don't support mmapping of certain resources, so be sure to check the return |
58 | value from any attempted mmap. | 60 | value from any attempted mmap. |
59 | 61 | ||
62 | The 'enable' file provides a counter that indicates how many times the device | ||
63 | has been enabled. If the 'enable' file currently returns '4', and a '1' is | ||
64 | echoed into it, it will then return '5'. Echoing a '0' into it will decrease | ||
65 | the count. Even when it returns to 0, though, some of the initialisation | ||
66 | may not be reversed. | ||
67 | |||
60 | The 'rom' file is special in that it provides read-only access to the device's | 68 | The 'rom' file is special in that it provides read-only access to the device's |
61 | ROM file, if available. It's disabled by default, however, so applications | 69 | ROM file, if available. It's disabled by default, however, so applications |
62 | should write the string "1" to the file to enable it before attempting a read | 70 | should write the string "1" to the file to enable it before attempting a read |
63 | call, and disable it following the access by writing "0" to the file. | 71 | call, and disable it following the access by writing "0" to the file. Note |
72 | that the device must be enabled for a rom read to return data succesfully. | ||
73 | In the event a driver is not bound to the device, it can be enabled using the | ||
74 | 'enable' file, documented above. | ||
64 | 75 | ||
65 | Accessing legacy resources through sysfs | 76 | Accessing legacy resources through sysfs |
66 | ---------------------------------------- | 77 | ---------------------------------------- |