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author | Chris Wilson <chris@chris-wilson.co.uk> | 2010-11-22 08:51:36 +0000 |
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committer | Chris Wilson <chris@chris-wilson.co.uk> | 2010-11-22 08:51:36 +0000 |
commit | e624ae8e0d4243e71daedce7570e91290438eaca (patch) | |
tree | e2b9804379a6aab3d2471898d257fe5590feb70c /Documentation/gpio.txt | |
parent | c4a1d9e4dc5d5313cfec2cc0c9d630efe8a6f287 (diff) | |
parent | 4ab0fbd3a29067e1540f05093ae4ed07645d18c8 (diff) | |
download | talos-op-linux-e624ae8e0d4243e71daedce7570e91290438eaca.tar.gz talos-op-linux-e624ae8e0d4243e71daedce7570e91290438eaca.zip |
Merge branch 'drm-intel-fixes' into drm-intel-next
Conflicts:
drivers/gpu/drm/i915/i915_gem.c
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 9633da01ff46..792faa3c06cf 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. |