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

[MyungJoo Ham]

On Mon, Jul 4, 2011 at 12:40 PM, Changhwan Youn <chaos.youn at samsung.com> wrote:
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>        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>
[]
>>
>> -     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

Ah.. ok, I'll let them go through the error handling code like other errors do.

Thanks.


- MyungJoo

>
>>   err_nortc:
>>       s3c_rtc_enable(pdev, 0);
>>       clk_disable(rtc_clk);
>> --
>> 1.7.4.1
>>
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>> before submitting a driver.
>
>



-- 
MyungJoo Ham, Ph.D.
Mobile Software Platform Lab,
Digital Media and Communications (DMC) Business
Samsung Electronics
cell: 82-10-6714-2858