path: root/Documentation/ABI/testing
diff options
authorBruno Prémont <bonbons@linux-vserver.org>2010-03-30 22:34:30 +0200
committerJiri Kosina <jkosina@suse.cz>2010-03-31 11:21:29 +0200
commitb8c21cf697d165999cc21a90e6caa73690ac6190 (patch)
tree795001ad27187193af60ca856a19790c9c29e122 /Documentation/ABI/testing
parent236db47c2b3b69464d50c695ab2ddd516cf64520 (diff)
HID: add framebuffer support to PicoLCD device
Add framebuffer support to PicoLCD device with use of deferred-io. Only changed areas of framebuffer get sent to device in order to save USB bandwidth and especially resources on PicoLCD device or allow higher refresh rate for a small area. Changed tiles are determined while updating shadow framebuffer. Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'Documentation/ABI/testing')
1 files changed, 17 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-driver-hid-picolcd b/Documentation/ABI/testing/sysfs-driver-hid-picolcd
index 6fb4f21469f..14f52d70621 100644
--- a/Documentation/ABI/testing/sysfs-driver-hid-picolcd
+++ b/Documentation/ABI/testing/sysfs-driver-hid-picolcd
@@ -15,3 +15,20 @@ Description: Make it possible to switch the PicoLCD device between LCD
disconnected and reconnects after above delay (default value
is 5 seconds though this default should not be relied on).
+What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/fb_update_rate
+Date: March 2010
+Contact: Bruno Prémont <bonbons@linux-vserver.org>
+Description: Make it possible to adjust defio refresh rate.
+ Reading: returns list of available refresh rates (expressed in Hz),
+ the active refresh rate being enclosed in brackets ('[' and ']')
+ Writing: accepts new refresh rate expressed in integer Hz
+ within permitted rates.
+ Note: As device can barely do 2 complete refreshes a second
+ it only makes sense to adjust this value if only one or two
+ tiles get changed and it's not appropriate to expect the application
+ to flush it's tiny changes explicitely at higher than default rate.