rtc: pxa: fix possible race condition

pxa_rtc_open() registers the interrupt handler which will access the RTC
registers. However, pxa_rtc_open() is called before the register range is
ioremapped. Instead, call it after devm_ioremap().

Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
diff --git a/drivers/rtc/rtc-pxa.c b/drivers/rtc/rtc-pxa.c
index fe4985b..47304f5 100644
--- a/drivers/rtc/rtc-pxa.c
+++ b/drivers/rtc/rtc-pxa.c
@@ -348,7 +348,7 @@ static int __init pxa_rtc_probe(struct platform_device *pdev)
 		dev_err(dev, "No alarm IRQ resource defined\n");
 		return -ENXIO;
 	}
-	pxa_rtc_open(dev);
+
 	pxa_rtc->base = devm_ioremap(dev, pxa_rtc->ress->start,
 				resource_size(pxa_rtc->ress));
 	if (!pxa_rtc->base) {
@@ -356,6 +356,8 @@ static int __init pxa_rtc_probe(struct platform_device *pdev)
 		return -ENOMEM;
 	}
 
+	pxa_rtc_open(dev);
+
 	sa1100_rtc->rcnr = pxa_rtc->base + 0x0;
 	sa1100_rtc->rtsr = pxa_rtc->base + 0x8;
 	sa1100_rtc->rtar = pxa_rtc->base + 0x4;