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rtc: max77686: Use usleep_range() instead of msleep() 

Documentation/timers/timers-howto.txt suggest to use usleep_range()
instead of msleep() for small msec (1ms - 20ms) since msleep() will
often sleep for 20ms for any value in that range.

This is fine in this case since 16ms is the _minimum_ delay required
by max77686 for an RTC update but by using usleep_range() instead of
msleep(), the driver can support other RTC IP blocks with a shorter
minimum delay (i.e: in the range of usecs instead of msecs).

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Andi Shyti <andi.shyti@samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
This commit is contained in:
Javier Martinez Canillas 2016-01-27 00:36:39 -03:00 committed by Alexandre Belloni
parent 862f9453bd
commit 5981804b83
1 changed files with 3 additions and 2 deletions
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5
drivers/rtc/rtc-max77686.c
View File

@ -41,7 +41,7 @@
#define ALARM_ENABLE_SHIFT 7
#define ALARM_ENABLE_MASK (1 << ALARM_ENABLE_SHIFT)
#define MAX77686_RTC_UPDATE_DELAY 16
#define MAX77686_RTC_UPDATE_DELAY 16000
enum {
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);
}
return ret;