From 62d1760180c84cba68cc83696fa0bde0593007bd Mon Sep 17 00:00:00 2001 From: MyungJoo Ham Date: Thu, 25 Aug 2011 15:59:24 -0700 Subject: [PATCH] drivers/rtc/rtc-s3c.c: allow multiple open / allow no-ioctl-open'ed rtc to have irq. The previous rtc-s3c had two issues related with its IRQ. 1. Users cannot open rtc multiple times because an open operation calls request_irq on the same IRQ. (e.g., two user processes wants to open and read RTC time from rtc-s3c at the same time) 2. If alarm is set and no one has the rtc opened with filesystem (either the alarm is set by kernel/boot-loader or user set an alarm and closed rtc dev file), the pending bit is not cleared and no further interrupt is invoked. When the alarm is used by the system itself such as a resume from suspend-to-RAM or other Low-power modes/idle, this is a critical issue. This patch mitigates these issues by calling request_irq at probe and free_irq at remove. Signed-off-by: MyungJoo Ham Signed-off-by: Kyungmin Park Acked-by: Kukjin Kim Cc: Alessandro Zummo Cc: Changhwan Youn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rtc/rtc-s3c.c | 67 ++++++++++++++++--------------------------- 1 file changed, 25 insertions(+), 42 deletions(-) diff --git a/drivers/rtc/rtc-s3c.c b/drivers/rtc/rtc-s3c.c index 067207afc086..4e7c04e773e0 100644 --- a/drivers/rtc/rtc-s3c.c +++ b/drivers/rtc/rtc-s3c.c @@ -319,49 +319,7 @@ static int s3c_rtc_proc(struct device *dev, struct seq_file *seq) return 0; } -static int s3c_rtc_open(struct device *dev) -{ - struct platform_device *pdev = to_platform_device(dev); - struct rtc_device *rtc_dev = platform_get_drvdata(pdev); - int ret; - - ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq, - IRQF_DISABLED, "s3c2410-rtc alarm", rtc_dev); - - if (ret) { - dev_err(dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret); - return ret; - } - - ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq, - IRQF_DISABLED, "s3c2410-rtc tick", rtc_dev); - - if (ret) { - dev_err(dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret); - goto tick_err; - } - - return ret; - - tick_err: - free_irq(s3c_rtc_alarmno, rtc_dev); - return ret; -} - -static void s3c_rtc_release(struct device *dev) -{ - struct platform_device *pdev = to_platform_device(dev); - struct rtc_device *rtc_dev = platform_get_drvdata(pdev); - - /* do not clear AIE here, it may be needed for wake */ - - free_irq(s3c_rtc_alarmno, rtc_dev); - free_irq(s3c_rtc_tickno, rtc_dev); -} - static const struct rtc_class_ops s3c_rtcops = { - .open = s3c_rtc_open, - .release = s3c_rtc_release, .read_time = s3c_rtc_gettime, .set_time = s3c_rtc_settime, .read_alarm = s3c_rtc_getalarm, @@ -425,6 +383,9 @@ static int __devexit s3c_rtc_remove(struct platform_device *dev) { struct rtc_device *rtc = platform_get_drvdata(dev); + free_irq(s3c_rtc_alarmno, rtc); + free_irq(s3c_rtc_tickno, rtc); + platform_set_drvdata(dev, NULL); rtc_device_unregister(rtc); @@ -548,10 +509,32 @@ static int __devinit s3c_rtc_probe(struct platform_device *pdev) s3c_rtc_setfreq(&pdev->dev, 1); + ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq, + IRQF_DISABLED, "s3c2410-rtc alarm", rtc); + if (ret) { + dev_err(&pdev->dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret); + goto err_alarm_irq; + } + + ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq, + IRQF_DISABLED, "s3c2410-rtc tick", rtc); + if (ret) { + dev_err(&pdev->dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret); + free_irq(s3c_rtc_alarmno, rtc); + goto err_tick_irq; + } + clk_disable(rtc_clk); return 0; + err_tick_irq: + free_irq(s3c_rtc_alarmno, rtc); + + err_alarm_irq: + platform_set_drvdata(pdev, NULL); + rtc_device_unregister(rtc); + err_nortc: s3c_rtc_enable(pdev, 0); clk_disable(rtc_clk);