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rtc: ep93xx: Initialize drvdata before registering device

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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 11:46:15 +02:00 committed by John Stultz
parent f4e708ae8e
commit 92d921c5de
1 changed files with 2 additions and 3 deletions
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5
drivers/rtc/rtc-ep93xx.c
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@ -151,6 +151,7 @@ static int __init ep93xx_rtc_probe(struct platform_device *pdev)
return -ENXIO;
pdev->dev.platform_data = ep93xx_rtc;
platform_set_drvdata(pdev, rtc);
rtc = rtc_device_register(pdev->name,
&pdev->dev, &ep93xx_rtc_ops, THIS_MODULE);
@ -159,8 +160,6 @@ static int __init ep93xx_rtc_probe(struct platform_device *pdev)
goto exit;
}
platform_set_drvdata(pdev, rtc);
err = sysfs_create_group(&pdev->dev.kobj, &ep93xx_rtc_sysfs_files);
if (err)
goto fail;
@ -168,9 +167,9 @@ static int __init ep93xx_rtc_probe(struct platform_device *pdev)
return 0;
fail:
platform_set_drvdata(pdev, NULL);
rtc_device_unregister(rtc);
exit:
platform_set_drvdata(pdev, NULL);
pdev->dev.platform_data = NULL;
return err;
}