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| author | Jiri Kosina <jkosina@suse.cz> | 2010-12-22 18:57:02 +0100 |
|---|---|---|
| committer | Jiri Kosina <jkosina@suse.cz> | 2010-12-22 18:57:02 +0100 |
| commit | 4b7bd364700d9ac8372eff48832062b936d0793b (patch) | |
| tree | 0dbf78c95456a0b02d07fcd473281f04a87e266d /Documentation/gpio.txt | |
| parent | c0d8768af260e2cbb4bf659ae6094a262c86b085 (diff) | |
| parent | 90a8a73c06cc32b609a880d48449d7083327e11a (diff) | |
Merge branch 'master' into for-next
Conflicts:
MAINTAINERS
arch/arm/mach-omap2/pm24xx.c
drivers/scsi/bfa/bfa_fcpim.c
Needed to update to apply fixes for which the old branch was too
outdated.
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 9633da01ff4..792faa3c06c 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. |