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| author | Ben Hutchings <bhutchings@solarflare.com> | 2008-12-23 03:08:29 +0000 |
|---|---|---|
| committer | Jesse Barnes <jbarnes@virtuousgeek.org> | 2009-01-07 11:13:23 -0800 |
| commit | 6a479079c07211bf348ac8a79754f26bea258f26 (patch) | |
| tree | 1587c0ed9446c7d0d6ab8a38d1524132e2faae35 /Documentation/PCI | |
| parent | b8d9cb2a2226118fd71f657c80b06b670a653022 (diff) | |
| download | kernel-common-6a479079c07211bf348ac8a79754f26bea258f26.tar.gz kernel-common-6a479079c07211bf348ac8a79754f26bea258f26.tar.bz2 kernel-common-6a479079c07211bf348ac8a79754f26bea258f26.zip | |
PCI: Add pci_clear_master() as opposite of pci_set_master()
During an online device reset it may be useful to disable bus-mastering.
pci_disable_device() does that, and far more besides, so is not suitable
for an online reset.
Add pci_clear_master() which does just this.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Diffstat (limited to 'Documentation/PCI')
| -rw-r--r-- | Documentation/PCI/pci.txt | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/Documentation/PCI/pci.txt b/Documentation/PCI/pci.txt index fd4907a2968c..7f6de6ea5b47 100644 --- a/Documentation/PCI/pci.txt +++ b/Documentation/PCI/pci.txt @@ -294,7 +294,8 @@ NOTE: pci_enable_device() can fail! Check the return value. pci_set_master() will enable DMA by setting the bus master bit in the PCI_COMMAND register. It also fixes the latency timer value if -it's set to something bogus by the BIOS. +it's set to something bogus by the BIOS. pci_clear_master() will +disable DMA by clearing the bus master bit. If the PCI device can use the PCI Memory-Write-Invalidate transaction, call pci_set_mwi(). This enables the PCI_COMMAND bit for Mem-Wr-Inval |