From: Peter Popovec <popovec@fei.tuke.sk>
Date: Wed, 22 Oct 2008 09:22:01 +0000 (+0200)
Subject: Check for timer resolution before start
X-Git-Url: http://zub.fei.tuke.sk/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c17147292dba706cda92a6835e11cbf25e847da0;p=walkera0701-joystick

Check for timer resolution before start
---

diff --git a/walkera0701.c b/walkera0701.c
index adb0d14..ec8c344 100644
--- a/walkera0701.c
+++ b/walkera0701.c
@@ -311,6 +311,12 @@ static int walkera0701_connect(int parport)
 
 static int __init walkera0701_init(void)
 {
+	struct timespec tp;
+	hrtimer_get_res(CLOCK_MONOTONIC, &tp);
+	if (tp.tv_sec != 0 || tp.tv_nsec > (BIN0_PULSE / 2)) {
+		printk(KERN_ERR "walkera0701: timer resolution out of range\n");
+		return (EFAULT);
+	}
 	hrtimer_init(&walkera0701_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 	walkera0701_timer.function = walkera0701_timer_handler;
 	return walkera0701_connect(walkera0701_pp_no);