1 files changed, 15 insertions, 6 deletions
diff --git a/Documentation/filesystems/sysfs-pci.txt b/Documentation/filesystems/sysfs-pci.txt
index 988a62fae11f..7ba2baa165ff 100644
--- a/Documentation/filesystems/sysfs-pci.txt
+++ b/Documentation/filesystems/sysfs-pci.txt
@@ -1,4 +1,5 @@
 Accessing PCI device resources through sysfs
+--------------------------------------------
 sysfs, usually mounted at /sys, provides access to PCI resources on platforms
 that support it.  For example, a given bus might look like this:
@@ -47,14 +48,21 @@ files, each with their own function.
  binary - file contains binary data
  cpumask - file contains a cpumask type
-The read only files are informational, writes to them will be ignored.
+The read only files are informational, writes to them will be ignored, with
-Writable files can be used to perform actions on the device (e.g. changing
+the exception of the 'rom' file.  Writable files can be used to perform
-config space, detaching a device).  mmapable files are available via an
+actions on the device (e.g. changing config space, detaching a device).
-mmap of the file at offset 0 and can be used to do actual device programming
+mmapable files are available via an mmap of the file at offset 0 and can be
-from userspace.  Note that some platforms don't support mmapping of certain
+used to do actual device programming from userspace.  Note that some platforms
-resources, so be sure to check the return value from any attempted mmap.
+don't support mmapping of certain resources, so be sure to check the return
+value from any attempted mmap.
+The 'rom' file is special in that it provides read-only access to the device's
+ROM file, if available.  It's disabled by default, however, so applications
+should write the string "1" to the file to enable it before attempting a read
+call, and disable it following the access by writing "0" to the file.
 Accessing legacy resources through sysfs
+----------------------------------------
 Legacy I/O port and ISA memory resources are also provided in sysfs if the
 underlying platform supports them.  They're located in the PCI class heirarchy,
@@ -75,6 +83,7 @@ simply dereference the returned pointer (after checking for errors of course)
 to access legacy memory space.
 Supporting PCI access on new platforms
+--------------------------------------
 In order to support PCI resource mapping as described above, Linux platform
 code must define HAVE_PCI_MMAP and provide a pci_mmap_page_range function.

diff --git a/Documentation/filesystems/sysfs-pci.txt b/Documentation/filesystems/sysfs-pci.txt index 988a62fae11f..7ba2baa165ff 100644 --- a/Documentation/filesystems/sysfs-pci.txt +++ b/Documentation/filesystems/sysfs-pci.txt
@@ -1,4 +1,5 @@
1	Accessing PCI device resources through sysfs	1	Accessing PCI device resources through sysfs
		2	--------------------------------------------
2		3
3	sysfs, usually mounted at /sys, provides access to PCI resources on platforms	4	sysfs, usually mounted at /sys, provides access to PCI resources on platforms
4	that support it. For example, a given bus might look like this:	5	that support it. For example, a given bus might look like this:
@@ -47,14 +48,21 @@ files, each with their own function.
47	binary - file contains binary data	48	binary - file contains binary data
48	cpumask - file contains a cpumask type	49	cpumask - file contains a cpumask type
49		50
50	The read only files are informational, writes to them will be ignored.	51	The read only files are informational, writes to them will be ignored, with
51	Writable files can be used to perform actions on the device (e.g. changing	52	the exception of the 'rom' file. Writable files can be used to perform
52	config space, detaching a device). mmapable files are available via an	53	actions on the device (e.g. changing config space, detaching a device).
53	mmap of the file at offset 0 and can be used to do actual device programming	54	mmapable files are available via an mmap of the file at offset 0 and can be
54	from userspace. Note that some platforms don't support mmapping of certain	55	used to do actual device programming from userspace. Note that some platforms
55	resources, so be sure to check the return value from any attempted mmap.	56	don't support mmapping of certain resources, so be sure to check the return
		57	value from any attempted mmap.
		58
		59	The 'rom' file is special in that it provides read-only access to the device's
		60	ROM file, if available. It's disabled by default, however, so applications
		61	should write the string "1" to the file to enable it before attempting a read
		62	call, and disable it following the access by writing "0" to the file.
56		63
57	Accessing legacy resources through sysfs	64	Accessing legacy resources through sysfs
		65	----------------------------------------
58		66
59	Legacy I/O port and ISA memory resources are also provided in sysfs if the	67	Legacy I/O port and ISA memory resources are also provided in sysfs if the
60	underlying platform supports them. They're located in the PCI class heirarchy,	68	underlying platform supports them. They're located in the PCI class heirarchy,
@@ -75,6 +83,7 @@ simply dereference the returned pointer (after checking for errors of course)
75	to access legacy memory space.	83	to access legacy memory space.
76		84
77	Supporting PCI access on new platforms	85	Supporting PCI access on new platforms
		86	--------------------------------------
78		87
79	In order to support PCI resource mapping as described above, Linux platform	88	In order to support PCI resource mapping as described above, Linux platform
80	code must define HAVE_PCI_MMAP and provide a pci_mmap_page_range function.	89	code must define HAVE_PCI_MMAP and provide a pci_mmap_page_range function.