rtc: bunch of drivers: fix 'no irq' case handing

This patch fixes a bunch of irq checking misuses.  Most drivers were
getting irq via platform_get_irq(), which returns -ENXIO or r->start.

rtc-cmos.c is special.  It is using PNP and platform bindings.  Hopefully
nobody is using PNP IRQ 0 for RTC.  So the changes should be safe.

rtc-sh.c is using platform_get_irq, but was storing a result into an
unsigned type, then was checking for < 0.  This is fixed now.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 7 insertions, 8 deletions

diff --git a/drivers/rtc/rtc-stk17ta8.c b/drivers/rtc/rtc-stk17ta8.c
index f4cd46e15af..dc0b6224ad9 100644
--- a/drivers/rtc/rtc-stk17ta8.c
+++ b/drivers/rtc/rtc-stk17ta8.c
@@ -170,7 +170,7 @@ static int stk17ta8_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 	struct platform_device *pdev = to_platform_device(dev);
 	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
 
-	if (pdata->irq < 0)
+	if (pdata->irq <= 0)
 		return -EINVAL;
 	pdata->alrm_mday = alrm->time.tm_mday;
 	pdata->alrm_hour = alrm->time.tm_hour;
@@ -187,7 +187,7 @@ static int stk17ta8_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 	struct platform_device *pdev = to_platform_device(dev);
 	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
 
-	if (pdata->irq < 0)
+	if (pdata->irq <= 0)
 		return -EINVAL;
 	alrm->time.tm_mday = pdata->alrm_mday < 0 ? 0 : pdata->alrm_mday;
 	alrm->time.tm_hour = pdata->alrm_hour < 0 ? 0 : pdata->alrm_hour;
@@ -221,7 +221,7 @@ static int stk17ta8_rtc_ioctl(struct device *dev, unsigned int cmd,
 	struct platform_device *pdev = to_platform_device(dev);
 	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
 
-	if (pdata->irq < 0)
+	if (pdata->irq <= 0)
 		return -ENOIOCTLCMD; /* fall back into rtc-dev's emulation */
 	switch (cmd) {
 	case RTC_AIE_OFF:
@@ -303,7 +303,6 @@ static int __init stk17ta8_rtc_probe(struct platform_device *pdev)
 	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
 	if (!pdata)
 		return -ENOMEM;
-	pdata->irq = -1;
 	if (!request_mem_region(res->start, RTC_REG_SIZE, pdev->name)) {
 		ret = -EBUSY;
 		goto out;
@@ -329,13 +328,13 @@ static int __init stk17ta8_rtc_probe(struct platform_device *pdev)
 	if (readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_PF)
 		dev_warn(&pdev->dev, "voltage-low detected.\n");
 
-	if (pdata->irq >= 0) {
+	if (pdata->irq > 0) {
 		writeb(0, ioaddr + RTC_INTERRUPTS);
 		if (request_irq(pdata->irq, stk17ta8_rtc_interrupt,
 				IRQF_DISABLED | IRQF_SHARED,
 				pdev->name, pdev) < 0) {
 			dev_warn(&pdev->dev, "interrupt not available.\n");
-			pdata->irq = -1;
+			pdata->irq = 0;
 		}
 	}
 
@@ -355,7 +354,7 @@ static int __init stk17ta8_rtc_probe(struct platform_device *pdev)
  out:
 	if (pdata->rtc)
 		rtc_device_unregister(pdata->rtc);
-	if (pdata->irq >= 0)
+	if (pdata->irq > 0)
 		free_irq(pdata->irq, pdev);
 	if (ioaddr)
 		iounmap(ioaddr);
@@ -371,7 +370,7 @@ static int __devexit stk17ta8_rtc_remove(struct platform_device *pdev)
 
 	sysfs_remove_bin_file(&pdev->dev.kobj, &stk17ta8_nvram_attr);
 	rtc_device_unregister(pdata->rtc);
-	if (pdata->irq >= 0) {
+	if (pdata->irq > 0) {
 		writeb(0, pdata->ioaddr + RTC_INTERRUPTS);
 		free_irq(pdata->irq, pdev);
 	}