rtc: davinci: Initialize drvdata before registering device
Commit f44f7f96a20 ("RTC: Initialize kernel state from RTC") uncovered
an issue in a number of RTC drivers, where the drivers call
rtc_device_register before initializing the device or platform drvdata.
This frequently results in null pointer dereferences when the
rtc_device_register immediately makes use of the rtc device, calling
rtc_read_alarm.
The solution is to ensure the drvdata is initialized prior to registering
the rtc device.
CC: Alessandro Zummo <a.zummo@towertech.it>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: rtc-linux@googlegroups.com
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
[fixed up commit log -jstultz]
Signed-off-by: John Stultz <john.stultz@linaro.org>
diff --git a/drivers/rtc/rtc-davinci.c b/drivers/rtc/rtc-davinci.c
index 8d46838..755e1fe 100644
--- a/drivers/rtc/rtc-davinci.c
+++ b/drivers/rtc/rtc-davinci.c
@@ -524,6 +524,8 @@
goto fail2;
}
+ platform_set_drvdata(pdev, davinci_rtc);
+
davinci_rtc->rtc = rtc_device_register(pdev->name, &pdev->dev,
&davinci_rtc_ops, THIS_MODULE);
if (IS_ERR(davinci_rtc->rtc)) {
@@ -553,8 +555,6 @@
rtcss_write(davinci_rtc, PRTCSS_RTC_CCTRL_CAEN, PRTCSS_RTC_CCTRL);
- platform_set_drvdata(pdev, davinci_rtc);
-
device_init_wakeup(&pdev->dev, 0);
return 0;
@@ -562,6 +562,7 @@
fail4:
rtc_device_unregister(davinci_rtc->rtc);
fail3:
+ platform_set_drvdata(pdev, NULL);
iounmap(davinci_rtc->base);
fail2:
release_mem_region(davinci_rtc->pbase, davinci_rtc->base_size);
