diff options
| -rw-r--r-- | drivers/regulator/core.c | 38 |
1 files changed, 33 insertions, 5 deletions
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index ad154247bb90..5075ed1e94a6 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1740,11 +1740,39 @@ static int _regulator_do_enable(struct regulator_dev *rdev) * together. */ trace_regulator_enable_delay(rdev_get_name(rdev)); - if (delay >= 1000) { - mdelay(delay / 1000); - udelay(delay % 1000); - } else if (delay) { - udelay(delay); + /* + * Delay for the requested amount of time as per the guidelines in: + * + * Documentation/timers/timers-howto.txt + * + * The assumption here is that regulators will never be enabled in + * atomic context and therefore sleeping functions can be used. + */ + if (delay) { + unsigned int ms = delay / 1000; + unsigned int us = delay % 1000; + + if (ms > 0) { + /* + * For small enough values, handle super-millisecond + * delays in the usleep_range() call below. + */ + if (ms < 20) + us += ms * 1000; + else + msleep(ms); + } + + /* + * Give the scheduler some room to coalesce with any other + * wakeup sources. For delays shorter than 10 us, don't even + * bother setting up high-resolution timers and just busy- + * loop. + */ + if (us >= 10) + usleep_range(us, us + 100); + else + udelay(us); } trace_regulator_enable_complete(rdev_get_name(rdev)); |