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author | J. Bruce Fields <bfields@redhat.com> | 2010-12-17 13:29:07 -0500 |
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committer | J. Bruce Fields <bfields@redhat.com> | 2010-12-17 13:29:07 -0500 |
commit | ec66ee3797e5848356cf593c6ec7aabf30a00cf1 (patch) | |
tree | 7ed5c84cc914644ffa1cd1b6a2b45db53fc224e8 /Documentation/gpio.txt | |
parent | 1205065764f2eda3216ebe213143f69891ee3460 (diff) | |
parent | b0c3844d8af6b9f3f18f31e1b0502fbefa2166be (diff) | |
download | op-kernel-dev-ec66ee3797e5848356cf593c6ec7aabf30a00cf1.zip op-kernel-dev-ec66ee3797e5848356cf593c6ec7aabf30a00cf1.tar.gz |
Merge commit 'v2.6.37-rc6' into for-2.6.38
Diffstat (limited to 'Documentation/gpio.txt')
-rw-r--r-- | Documentation/gpio.txt | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/Documentation/gpio.txt b/Documentation/gpio.txt index 9633da0..792faa3 100644 --- a/Documentation/gpio.txt +++ b/Documentation/gpio.txt @@ -617,6 +617,16 @@ and have the following read/write attributes: is configured as an output, this value may be written; any nonzero value is treated as high. + If the pin can be configured as interrupt-generating interrupt + and if it has been configured to generate interrupts (see the + description of "edge"), you can poll(2) on that file and + poll(2) will return whenever the interrupt was triggered. If + you use poll(2), set the events POLLPRI and POLLERR. If you + use select(2), set the file descriptor in exceptfds. After + poll(2) returns, either lseek(2) to the beginning of the sysfs + file and read the new value or close the file and re-open it + to read the value. + "edge" ... reads as either "none", "rising", "falling", or "both". Write these strings to select the signal edge(s) that will make poll(2) on the "value" file return. |