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regulator: bd718x7: Clarify comment by moving it

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The BD718x7 needs to disable voltage monitoring for a duration of
certain voltage changes.

The comment explaining use of msleep(1) instead of a more accurate
delay(), was placed to a function which disabled the protection. The
actual sleeping is done in a different place of the code, after the
voltage has been changed.

Browsing through the comment and code after the years made me to scratch
my head for a second. I may have figured why me and so many fellow
developers are slowly getting bald.

Clarify things a bit and move the comment about required delay directly
above the sleep. Leave only a small comment explaining why the protection
is disabled to the spot where the logic for disabling is.

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Link: https://patch.msgid.link/a90cb77e66a253f4055bbb99672dc81c7457de66.1749533040.git.mazziesaccount@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Matti Vaittinen 2025-06-10 08:32:06 +03:00 committed by Mark Brown
parent d6fa0ca959
commit 55d9fd9819
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GPG Key ID: 24D68B725D5487D0
1 changed files with 14 additions and 13 deletions
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27
drivers/regulator/bd718x7-regulator.c
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@ -134,9 +134,19 @@ static void voltage_change_done(struct regulator_dev *rdev, unsigned int sel,
if (*mask) {
/*
* Let's allow scheduling as we use I2C anyways. We just need to
* guarantee minimum of 1ms sleep - it shouldn't matter if we
* exceed it due to the scheduling.
* We had fault detection disabled for the duration of the
* voltage change.
*
* According to HW colleagues the maximum time it takes is
* 1000us. I assume that on systems with light load this
* might be less - and we could probably use DT to give
* system specific delay value if performance matters.
*
* Well, knowing we use I2C here and can add scheduling delays
* I don't think it is worth the hassle and I just add fixed
* 1ms sleep here (and allow scheduling). If this turns out to
* be a problem we can change it to delay and make the delay
* time configurable.
*/
msleep(1);
@ -173,16 +183,7 @@ static int voltage_change_prepare(struct regulator_dev *rdev, unsigned int sel,
/*
* If we increase LDO voltage when LDO is enabled we need to
* disable the power-good detection until voltage has reached
* the new level. According to HW colleagues the maximum time
* it takes is 1000us. I assume that on systems with light load
* this might be less - and we could probably use DT to give
* system specific delay value if performance matters.
*
* Well, knowing we use I2C here and can add scheduling delays
* I don't think it is worth the hassle and I just add fixed
* 1ms sleep here (and allow scheduling). If this turns out to
* be a problem we can change it to delay and make the delay
* time configurable.
* the new level.
*/
if (new > now) {
int tmp;