From 5f54c8a00af20e5cf38c3e5ef2f59b6848a17cd9 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Wed, 4 May 2011 17:31:27 +0200 Subject: 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 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-mxc.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) (limited to 'drivers/rtc/rtc-mxc.c') 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); -- cgit v1.2.3 From 9796cc964daf7f18b4cd84c86975b3bc3804ca5a Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Thu, 26 May 2011 16:25:12 -0700 Subject: drivers/rtc/rtc-mxc.c: remove defines already included in rtc.h [akpm@linux-foundation.org: retain the code comments] Signed-off-by: Wolfram Sang Cc: Vladimir Zapolskiy Cc: Alessandro Zummo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rtc/rtc-mxc.c | 6 ------ include/linux/rtc.h | 8 ++++---- 2 files changed, 4 insertions(+), 10 deletions(-) (limited to 'drivers/rtc/rtc-mxc.c') diff --git a/drivers/rtc/rtc-mxc.c b/drivers/rtc/rtc-mxc.c index d814417bee8c..39e41fbdf08b 100644 --- a/drivers/rtc/rtc-mxc.c +++ b/drivers/rtc/rtc-mxc.c @@ -55,12 +55,6 @@ static const u32 PIE_BIT_DEF[MAX_PIE_NUM][2] = { { MAX_PIE_FREQ, RTC_SAM7_BIT }, }; -/* Those are the bits from a classic RTC we want to mimic */ -#define RTC_IRQF 0x80 /* any of the following 3 is active */ -#define RTC_PF 0x40 /* Periodic interrupt */ -#define RTC_AF 0x20 /* Alarm interrupt */ -#define RTC_UF 0x10 /* Update interrupt for 1Hz RTC */ - #define MXC_RTC_TIME 0 #define MXC_RTC_ALARM 1 diff --git a/include/linux/rtc.h b/include/linux/rtc.h index 877ece45426f..b27ebea25660 100644 --- a/include/linux/rtc.h +++ b/include/linux/rtc.h @@ -92,10 +92,10 @@ struct rtc_pll_info { #define RTC_PLL_SET _IOW('p', 0x12, struct rtc_pll_info) /* Set PLL correction */ /* interrupt flags */ -#define RTC_IRQF 0x80 /* any of the following is active */ -#define RTC_PF 0x40 -#define RTC_AF 0x20 -#define RTC_UF 0x10 +#define RTC_IRQF 0x80 /* Any of the following is active */ +#define RTC_PF 0x40 /* Periodic interrupt */ +#define RTC_AF 0x20 /* Alarm interrupt */ +#define RTC_UF 0x10 /* Update interrupt for 1Hz RTC */ #ifdef __KERNEL__ -- cgit v1.2.3