rtc: davinci: Initialize drvdata before registering device

Commit f44f7f96a2 ("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>
This commit is contained in:
Wolfram Sang 2011-05-05 11:46:14 +02:00 committed by John Stultz
parent 5f54c8a00a
commit f4e708ae8e

View File

@ -524,6 +524,8 @@ static int __init davinci_rtc_probe(struct platform_device *pdev)
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 @@ static int __init davinci_rtc_probe(struct platform_device *pdev)
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 @@ static int __init davinci_rtc_probe(struct platform_device *pdev)
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);