Some regulators might need to verify that they have indeed been enabled after the enable() call is made and enable_time delay has passed.
This is implemented by repeatedly checking is_enabled() upto poll_enabled_time, waiting for the already calculated enable delay in each iteration. Signed-off-by: Sumit Semwal <[email protected]> --- drivers/regulator/core.c | 28 ++++++++++++++++++++++++++++ include/linux/regulator/driver.h | 5 +++++ 2 files changed, 33 insertions(+) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 7486f6e4e613..06199f182114 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -2409,6 +2409,34 @@ static int _regulator_do_enable(struct regulator_dev *rdev) _regulator_enable_delay(delay); + /* If set, poll upto poll_enabled_time uS to see if the regulator + * actually got enabled. + * For each iteration, wait for the enable_time delay calculated + * above already. + * If the regulator isn't enabled after poll_enabled_time has + * expired, return -ETIMEDOUT. + */ + if (rdev->desc->poll_enabled_time) { + unsigned int time_remaining = rdev->desc->poll_enabled_time; + + while (time_remaining > 0) { + /* We've already waited for enable_time above; + * so we can start with immediate check of the + * status of the regulator. + */ + if (rdev->desc->ops->is_enabled(rdev)) + break; + + _regulator_enable_delay(delay); + time_remaining -= delay; + } + + if (time_remaining <= 0) { + rdev_err(rdev, "Enabled check failed.\n"); + return -ETIMEDOUT; + } + } + trace_regulator_enable_complete(rdev_get_name(rdev)); return 0; diff --git a/include/linux/regulator/driver.h b/include/linux/regulator/driver.h index 29d920516e0b..bb50e943010f 100644 --- a/include/linux/regulator/driver.h +++ b/include/linux/regulator/driver.h @@ -322,6 +322,9 @@ enum regulator_type { * @enable_time: Time taken for initial enable of regulator (in uS). * @off_on_delay: guard time (in uS), before re-enabling a regulator * + * @poll_enabled_time: Maximum time (in uS) to poll if the regulator is + * actually enabled, after enable() call + * * @of_map_mode: Maps a hardware mode defined in a DeviceTree to a standard mode */ struct regulator_desc { @@ -389,6 +392,8 @@ struct regulator_desc { unsigned int off_on_delay; + unsigned int poll_enabled_time; + unsigned int (*of_map_mode)(unsigned int mode); }; -- 2.26.2
