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kernel os linux

regulator: bd718x7: Clarify comment by moving it

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>

authored by

Matti Vaittinen and committed by
Mark Brown
55d9fd98 d6fa0ca9

+14 -13
+14 -13
drivers/regulator/bd718x7-regulator.c
··· 134 134 135 135 if (*mask) { 136 136 /* 137 - * Let's allow scheduling as we use I2C anyways. We just need to 138 - * guarantee minimum of 1ms sleep - it shouldn't matter if we 139 - * exceed it due to the scheduling. 137 + * We had fault detection disabled for the duration of the 138 + * voltage change. 139 + * 140 + * According to HW colleagues the maximum time it takes is 141 + * 1000us. I assume that on systems with light load this 142 + * might be less - and we could probably use DT to give 143 + * system specific delay value if performance matters. 144 + * 145 + * Well, knowing we use I2C here and can add scheduling delays 146 + * I don't think it is worth the hassle and I just add fixed 147 + * 1ms sleep here (and allow scheduling). If this turns out to 148 + * be a problem we can change it to delay and make the delay 149 + * time configurable. 140 150 */ 141 151 msleep(1); 142 152 ··· 183 173 /* 184 174 * If we increase LDO voltage when LDO is enabled we need to 185 175 * disable the power-good detection until voltage has reached 186 - * the new level. According to HW colleagues the maximum time 187 - * it takes is 1000us. I assume that on systems with light load 188 - * this might be less - and we could probably use DT to give 189 - * system specific delay value if performance matters. 190 - * 191 - * Well, knowing we use I2C here and can add scheduling delays 192 - * I don't think it is worth the hassle and I just add fixed 193 - * 1ms sleep here (and allow scheduling). If this turns out to 194 - * be a problem we can change it to delay and make the delay 195 - * time configurable. 176 + * the new level. 196 177 */ 197 178 if (new > now) { 198 179 int tmp;