Messages in this thread | | | Date | Mon, 3 Dec 2012 13:35:38 +0800 | Subject | Re: [PATCH 1/4] rtc: sa1100: enable/disable rtc when probe/remove the device | From | Haojian Zhuang <> |
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On Mon, Dec 3, 2012 at 10:53 AM, Chao Xie <xiechao.mail@gmail.com> wrote: > On Mon, Dec 3, 2012 at 9:39 AM, Chao Xie <xiechao.mail@gmail.com> wrote: >> On Fri, Nov 30, 2012 at 3:04 PM, Haojian Zhuang >> <haojian.zhuang@gmail.com> wrote: >>> On Thu, Nov 29, 2012 at 6:25 PM, Russell King - ARM Linux >>> <linux@arm.linux.org.uk> wrote: >>>> On Wed, Nov 28, 2012 at 09:21:07PM -0500, Chao Xie wrote: >>>>> The original sa1100_rtc_open/sa1100_rtc_release will be called >>>>> when the /dev/rtc0 is opened or closed. >>>>> In fact, these two functions will enable/disable the clock, and >>>>> register/unregister the irqs. >>>>> User application will use /dev/rtc0 to read the rtc time or set >>>>> the alarm. The rtc should still run indepent of open/close the >>>>> rtc device. >>>>> So only enable clock and register the irqs when probe the device, >>>>> and disable clock and unregister the irqs when remove the device. >>>> >>>> NAK. I don't think you properly understand what's going on here if you >>>> think moving the entire open and release functions into the probe and >>>> remove functions is the right thing to do. >>> >>> Since PXA27x & PXA3xx supports dual rtc device at the same time, >>> user could choose use either of rtc at run time. Then clk & irq are setup >>> in open(). >>> >>> Chao, >>> So you shouldn't remove them into probe(). >> >> How can user to choose one RTC? >> The user API, for example "date" will open the device, get the time >> and then close the device. >> WHen set a alarm, it is the same routine. open->set->close. >> The open routine will enable clock and register irq, close will >> disable the clock and unregister irq. It means that if only open is >> invoked, rtc begins to work, and after close is invoked rtc stops >> working. It means that the user can not get correct time and can not >> get right alarm. > > hi > I want to correct what i said. For the irq register/unregister i think > can be done at open/release. But for clock enable/disable, i do not > think so. If clock is disabled, as i think RTC will not work. User API > still use open->get_time->close for "date" command. It means that RTC > will not return correct date to user.
I didn't get your point. Do you mean that RTC can't work without your patch?
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