[PATCH] rtc: fx error case

Ensure RTC driver doesn't use its timer when it doesn't get to set it up
(as it cannot currently prevent other of its functions to be called from
outside when not built as a module - probably this should also be
addressed).
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/char/rtc.c

@@ -958,6 +958,7 @@ static int __init rtc_init(void)
 		}
 	}
 #endif
+	rtc_has_irq = 0;
 	printk(KERN_ERR "rtc_init: no PC rtc found\n");
 	return -EIO;
 
@@ -972,6 +973,7 @@ static int __init rtc_init(void)
 	 * PCI Slot 2 INTA# (and some INTx# in Slot 1).
 	 */
 	if (request_irq(rtc_irq, rtc_interrupt, IRQF_SHARED, "rtc", (void *)&rtc_port)) {
+		rtc_has_irq = 0;
 		printk(KERN_ERR "rtc: cannot register IRQ %d\n", rtc_irq);
 		return -EIO;
 	}
@@ -982,6 +984,9 @@ static int __init rtc_init(void)
 	else
 		r = request_mem_region(RTC_PORT(0), RTC_IO_EXTENT, "rtc");
 	if (!r) {
+#ifdef RTC_IRQ
+		rtc_has_irq = 0;
+#endif
 		printk(KERN_ERR "rtc: I/O resource %lx is not free.\n",
 		       (long)(RTC_PORT(0)));
 		return -EIO;
@@ -996,6 +1001,7 @@ static int __init rtc_init(void)
 
 	if(request_irq(RTC_IRQ, rtc_int_handler_ptr, IRQF_DISABLED, "rtc", NULL)) {
 		/* Yeah right, seeing as irq 8 doesn't even hit the bus. */
+		rtc_has_irq = 0;
 		printk(KERN_ERR "rtc: IRQ %d is not free.\n", RTC_IRQ);
 		if (RTC_IOMAPPED)
 			release_region(RTC_PORT(0), RTC_IO_EXTENT);
@@ -1012,6 +1018,7 @@ static int __init rtc_init(void)
 	if (misc_register(&rtc_dev)) {
 #ifdef RTC_IRQ
 		free_irq(RTC_IRQ, NULL);
+		rtc_has_irq = 0;
 #endif
 		release_region(RTC_PORT(0), RTC_IO_EXTENT);
 		return -ENODEV;
@@ -1021,6 +1028,7 @@ static int __init rtc_init(void)
 	if (!ent) {
 #ifdef RTC_IRQ
 		free_irq(RTC_IRQ, NULL);
+		rtc_has_irq = 0;
 #endif
 		release_region(RTC_PORT(0), RTC_IO_EXTENT);
 		misc_deregister(&rtc_dev);