From patchwork Sat May 7 01:20:45 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [02/11] rtc: davinci: Initialize drvdata before registering device Date: Fri, 06 May 2011 15:20:45 -0000 From: John Stultz X-Patchwork-Id: 94456 Message-Id: <1304731254-3238-3-git-send-email-john.stultz@linaro.org> To: lkml Cc: Wolfram Sang , Alessandro Zummo , Thomas Gleixner , rtc-linux@googlegroups.com, John Stultz From: Wolfram Sang 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 CC: Thomas Gleixner CC: rtc-linux@googlegroups.com Signed-off-by: Wolfram Sang [fixed up commit log -jstultz] Signed-off-by: John Stultz --- drivers/rtc/rtc-davinci.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) 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 @@ 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);