[PATCH 3/3] rtc: rtc-s3c: allow multiple open / allow no-ioctl-open'ed rtc to have irq.

[Changhwan Youn]

AbwBwAGUAbgAgAC8AIAB
	hAGwAbABvAHcAIABuAG8ALQBpAG8AYwB0AGwALQBvAHAAZQBuACcAZQBkACAAcgB0AGMAIAB0AG8AIABoAGEAdgBlACAAaQByAHEALgA=
x-cr-puzzleid: {71A23705-5400-4E21-9C23-2B1E96E33A68}

MyungJoo Ham wrote:
> 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 issue by calling request_irq at probe and
> free_irq at remove.
> 
> Signed-off-by: MyungJoo Ham <myungjoo.ham at samsung.com>
> Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
> ---
>  drivers/rtc/rtc-s3c.c |   63
++++++++++++++-------------------------------
> ---
>  1 files changed, 19 insertions(+), 44 deletions(-)
> 
> diff --git a/drivers/rtc/rtc-s3c.c b/drivers/rtc/rtc-s3c.c
> index be85ea5..8d2807f 100644
> --- a/drivers/rtc/rtc-s3c.c
> +++ b/drivers/rtc/rtc-s3c.c
> @@ -320,50 +320,7 @@ 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,
> @@ -427,6 +384,9 @@ 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);
> 
> @@ -553,8 +513,23 @@ static int __devinit s3c_rtc_probe(struct
> platform_device *pdev)
> 
>  	clk_disable(rtc_clk);
> 
> -	return 0;
> +	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);
> +		return ret;
> +	}
> +
> +	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);
> +	}
> +
> +	return ret;

You need proper error handlings.

Regards,
Changhwan

>   err_nortc:
>  	s3c_rtc_enable(pdev, 0);
>  	clk_disable(rtc_clk);
> --
> 1.7.4.1
> 
> --
> You received this message because you are subscribed to "rtc-linux".
> Membership options at http://groups.google.com/group/rtc-linux .
> Please read http://groups.google.com/group/rtc-linux/web/checklist
> before submitting a driver.