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Re: [PATCH v2 03/10] rtc: max77686: Use usleep_range() instead of msleep()

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On Friday 22 January 2016 05:35 PM, Javier Martinez Canillas wrote:
> Hello Laxman,
>
> On 01/22/2016 06:41 AM, Laxman Dewangan wrote:
>>
>> On Friday 22 January 2016 01:53 AM, Javier Martinez Canillas wrote:
>>>       RTC_SEC = 0,
>>> @@ -130,7 +130,8 @@ static int max77686_rtc_update(struct 
>>> max77686_rtc_info *info,
>>>                   __func__, ret, data);
>>>       else {
>>>           /* Minimum 16ms delay required before RTC update. */
>>> -        msleep(MAX77686_RTC_UPDATE_DELAY);
>>> +        usleep_range(MAX77686_RTC_UPDATE_DELAY,
>>> +                 MAX77686_RTC_UPDATE_DELAY * 2);
>>>       }
>>>
>>
>> Instead of making usleep_range(16000, 32000), can we make small range as
>> usleep_range(16000, 17000)?
>>
>
> Yes, I also didn't know how to make the delay smaller. If I do for 
> example
>
> usleep_range(delay, delay + 10000), then the 10000 delta would be too big
> for max77802 (50 times the minimum required 200 delay).
>
> So I used delay * 2 for two reasons:
>
> 1) That way is generic enough and can work for any delay
>
> 2) My understanding is that most of times the delay should be precise and
>    is not that bad if sometimes the delay is the worst case (2 * X) since
>    after all the delay is the minimum required.
>
> I also see that usleep_range(X, X * 2) is a used pattern across the 
> kernel.

OK, fine to me here.

Acked-by: Laxman Dewangan <ldewangan@nvidia.com>

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[PATCH v2 00/10] rtc: max77686: Extend driver and add max77802 support Javier Martinez Canillas <javier@osg.samsung.com> - 2016-01-21 21:30 +0100
  [PATCH v2 01/10] rtc: max77686: Fix max77686_rtc_read_alarm() return value Javier Martinez Canillas <javier@osg.samsung.com> - 2016-01-21 21:30 +0100
    Re: [PATCH v2 01/10] rtc: max77686: Fix max77686_rtc_read_alarm()  return value Krzysztof Kozlowski <k.kozlowski@samsung.com> - 2016-01-22 02:00 +0100
    Re: [PATCH v2 01/10] rtc: max77686: Fix max77686_rtc_read_alarm()  return value Laxman Dewangan <ldewangan@nvidia.com> - 2016-01-22 10:50 +0100
  [PATCH v2 02/10] rtc: max77686: Use ARRAY_SIZE() instead of current array length Javier Martinez Canillas <javier@osg.samsung.com> - 2016-01-21 21:30 +0100
    Re: [PATCH v2 02/10] rtc: max77686: Use ARRAY_SIZE() instead of  current array length Krzysztof Kozlowski <k.kozlowski@samsung.com> - 2016-01-22 02:00 +0100
    Re: [PATCH v2 02/10] rtc: max77686: Use ARRAY_SIZE() instead of current  array length Laxman Dewangan <ldewangan@nvidia.com> - 2016-01-22 11:00 +0100
      Re: [PATCH v2 02/10] rtc: max77686: Use ARRAY_SIZE() instead of  current array length Javier Martinez Canillas <javier@osg.samsung.com> - 2016-01-22 12:50 +0100
  [PATCH v2 07/10] rtc: max77686: Use dev_warn() instead of pr_warn() Javier Martinez Canillas <javier@osg.samsung.com> - 2016-01-21 21:30 +0100
  [PATCH v2 03/10] rtc: max77686: Use usleep_range() instead of msleep() Javier Martinez Canillas <javier@osg.samsung.com> - 2016-01-21 21:30 +0100
    Re: [PATCH v2 03/10] rtc: max77686: Use usleep_range() instead of  msleep() Krzysztof Kozlowski <k.kozlowski@samsung.com> - 2016-01-22 02:10 +0100
    Re: [PATCH v2 03/10] rtc: max77686: Use usleep_range() instead of  msleep() Laxman Dewangan <ldewangan@nvidia.com> - 2016-01-22 11:00 +0100
      Re: [PATCH v2 03/10] rtc: max77686: Use usleep_range() instead of  msleep() Javier Martinez Canillas <javier@osg.samsung.com> - 2016-01-22 13:10 +0100
        Re: [PATCH v2 03/10] rtc: max77686: Use usleep_range() instead of  msleep() Laxman Dewangan <ldewangan@nvidia.com> - 2016-01-25 12:30 +0100
  [PATCH v2 10/10] ARM: multi_v7_defconfig: Remove MAX77802 RTC Kconfig symbol Javier Martinez Canillas <javier@osg.samsung.com> - 2016-01-21 21:30 +0100
    Re: [PATCH v2 10/10] ARM: multi_v7_defconfig: Remove MAX77802 RTC  Kconfig symbol Laxman Dewangan <ldewangan@nvidia.com> - 2016-01-22 11:10 +0100
      Re: [PATCH v2 10/10] ARM: multi_v7_defconfig: Remove MAX77802 RTC  Kconfig symbol Javier Martinez Canillas <javier@osg.samsung.com> - 2016-01-22 13:10 +0100
  [PATCH v2 09/10] ARM: exynos_defconfig: Remove MAX77802 RTC Kconfig symbol Javier Martinez Canillas <javier@osg.samsung.com> - 2016-01-21 21:30 +0100
  Re: [PATCH v2 00/10] rtc: max77686: Extend driver and add max77802  support Alexandre Belloni <alexandre.belloni@free-electrons.com> - 2016-01-25 17:30 +0100
    Re: [PATCH v2 00/10] rtc: max77686: Extend driver and add max77802  support Javier Martinez Canillas <javier@osg.samsung.com> - 2016-01-26 00:50 +0100

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