summaryrefslogtreecommitdiffstats
path: root/drivers/rtc
diff options
context:
space:
mode:
authorWolfram Sang <w.sang@pengutronix.de>2011-05-04 17:31:27 +0200
committerJohn Stultz <john.stultz@linaro.org>2011-05-06 17:40:10 -0700
commit5f54c8a00af20e5cf38c3e5ef2f59b6848a17cd9 (patch)
tree3fd5d20a1581314cfefe788bc5e9e74d57e1be3b /drivers/rtc
parent5895198c56d131cc696556a45f7ff0ea99ac297b (diff)
downloadlinux-5f54c8a00af20e5cf38c3e5ef2f59b6848a17cd9.tar.bz2
rtc: mxc: 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>
Diffstat (limited to 'drivers/rtc')
-rw-r--r--drivers/rtc/rtc-mxc.c19
1 files changed, 11 insertions, 8 deletions
diff --git a/drivers/rtc/rtc-mxc.c b/drivers/rtc/rtc-mxc.c
index 826ab64a8fa9..d814417bee8c 100644
--- a/drivers/rtc/rtc-mxc.c
+++ b/drivers/rtc/rtc-mxc.c
@@ -418,14 +418,6 @@ static int __init mxc_rtc_probe(struct platform_device *pdev)
goto exit_put_clk;
}
- rtc = rtc_device_register(pdev->name, &pdev->dev, &mxc_rtc_ops,
- THIS_MODULE);
- if (IS_ERR(rtc)) {
- ret = PTR_ERR(rtc);
- goto exit_put_clk;
- }
-
- pdata->rtc = rtc;
platform_set_drvdata(pdev, pdata);
/* Configure and enable the RTC */
@@ -438,8 +430,19 @@ static int __init mxc_rtc_probe(struct platform_device *pdev)
pdata->irq = -1;
}
+ rtc = rtc_device_register(pdev->name, &pdev->dev, &mxc_rtc_ops,
+ THIS_MODULE);
+ if (IS_ERR(rtc)) {
+ ret = PTR_ERR(rtc);
+ goto exit_clr_drvdata;
+ }
+
+ pdata->rtc = rtc;
+
return 0;
+exit_clr_drvdata:
+ platform_set_drvdata(pdev, NULL);
exit_put_clk:
clk_disable(pdata->clk);
clk_put(pdata->clk);