rtc: update documentation wrt irq_set_freq

Document the proper use of the irq_set_freq function.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mike Frysinger 2008-02-06 01:38:56 -08:00 committed by Linus Torvalds
parent fcd8db002f
commit 8a0ba4e017

View File

@ -182,8 +182,8 @@ driver returns ENOIOCTLCMD. Some common examples:
since the frequency is stored in the irq_freq member of the rtc_device
structure. Your driver needs to initialize the irq_freq member during
init. Make sure you check the requested frequency is in range of your
hardware in the irq_set_freq function. If you cannot actually change
the frequency, just return -ENOTTY.
hardware in the irq_set_freq function. If it isn't, return -EINVAL. If
you cannot actually change the frequency, do not define irq_set_freq.
If all else fails, check out the rtc-test.c driver!