diff options
| author | Rolf Eike Beer <eike-kernel@sf-tec.de> | 2007-07-19 17:48:44 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2007-08-22 14:48:40 -0700 |
| commit | 5ca24814247fa4c039b893bf80fc05d0e5d41b00 (patch) | |
| tree | fb1d19e094e5337e4a33d97ad487ce36c631d104 | |
| parent | 4e68fc97b17470365a65bc569523dd9012730e44 (diff) | |
| download | linux-5ca24814247fa4c039b893bf80fc05d0e5d41b00.tar.bz2 | |
PCI: Document pci_iomap()
This useful interface is hardly mentioned anywhere in the in-tree
documentation.
Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Tejun Heo <htejun@gmail.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | Documentation/DocBook/deviceiobook.tmpl | 3 | ||||
| -rw-r--r-- | include/asm-i386/io.h | 3 | ||||
| -rw-r--r-- | lib/iomap.c | 15 |
3 files changed, 19 insertions, 2 deletions
diff --git a/Documentation/DocBook/deviceiobook.tmpl b/Documentation/DocBook/deviceiobook.tmpl index 90ed23df1f68..c917de681ccd 100644 --- a/Documentation/DocBook/deviceiobook.tmpl +++ b/Documentation/DocBook/deviceiobook.tmpl @@ -316,7 +316,8 @@ CPU B: spin_unlock_irqrestore(&dev_lock, flags) <chapter id="pubfunctions"> <title>Public Functions Provided</title> -!Einclude/asm-i386/io.h +!Iinclude/asm-i386/io.h +!Elib/iomap.c </chapter> </book> diff --git a/include/asm-i386/io.h b/include/asm-i386/io.h index 7b65b5b00034..e8e0bd641120 100644 --- a/include/asm-i386/io.h +++ b/include/asm-i386/io.h @@ -112,6 +112,9 @@ extern void __iomem * __ioremap(unsigned long offset, unsigned long size, unsign * writew/writel functions and the other mmio helpers. The returned * address is not guaranteed to be usable directly as a virtual * address. + * + * If the area you are trying to map is a PCI BAR you should have a + * look at pci_iomap(). */ static inline void __iomem * ioremap(unsigned long offset, unsigned long size) diff --git a/lib/iomap.c b/lib/iomap.c index a57d262a5ed9..864f2ec1966e 100644 --- a/lib/iomap.c +++ b/lib/iomap.c @@ -240,7 +240,20 @@ void ioport_unmap(void __iomem *addr) EXPORT_SYMBOL(ioport_map); EXPORT_SYMBOL(ioport_unmap); -/* Create a virtual mapping cookie for a PCI BAR (memory or IO) */ +/** + * pci_iomap - create a virtual mapping cookie for a PCI BAR + * @dev: PCI device that owns the BAR + * @bar: BAR number + * @maxlen: length of the memory to map + * + * Using this function you will get a __iomem address to your device BAR. + * You can access it using ioread*() and iowrite*(). These functions hide + * the details if this is a MMIO or PIO address space and will just do what + * you expect from them in the correct way. + * + * @maxlen specifies the maximum length to map. If you want to get access to + * the complete BAR without checking for its length first, pass %0 here. + * */ void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) { unsigned long start = pci_resource_start(dev, bar); |