[U-Boot] [PATCH v4 2/2] regulator: bd718x7: support ROHM BD71837 and BD71847 PMICs

[Simon Glass]

> BD71837 and BD71847 is PMIC intended for powering single-core,
> dual-core, and quad-core SoC’s such as NXP-i.MX 8M. BD71847
> is used for example on NXP imx8mm EVK.
>
> Add regulator driver for ROHM BD71837 and BD71847 PMICs.
> BD71837 contains 8 bucks and 7 LDOS. BD71847 is reduced
> version containing 6 bucks and 6 LDOs. Voltages for DVS
> bucks (1-4 on BD71837, 1 and 2 on BD71847) can be adjusted
> when regulators are enabled. For other bucks and LDOs we may
> have over- or undershooting if voltage is adjusted when
> regulator is enabled. Thus this is prevented by default.
>
> BD718x7 has a quirk which may leave power output disabled
> after reset if enable/disable state was controlled by SW.
> Thus the SW control is only allowed for BD71837  bucks
> 3 and 4 by default. The impact of this limitation must be
> evaluated board-by board and restrictions may need to be
> modified. (Linux driver get's these limitations from DT and we
> may want to implement same on u-Boot driver).
>
> Signed-off-by: Matti Vaittinen <matti.vaittinen at fi.rohmeurope.com>
> ---
> Changelog v3 => v4:
> - prefer u8 over uint8_t
> - prefer types with natural alignment over u8 on function arguments
> - remove inclusion of errno.h from drivers/power/regulator/bd71837.c
>
>  drivers/power/pmic/bd71837.c      |  32 +-
>  drivers/power/regulator/Kconfig   |  17 ++
>  drivers/power/regulator/Makefile  |   1 +
>  drivers/power/regulator/bd71837.c | 468 ++++++++++++++++++++++++++++++
>  include/power/bd71837.h           | 147 ++++++----
>  5 files changed, 607 insertions(+), 58 deletions(-)
>  create mode 100644 drivers/power/regulator/bd71837.c

Reviewed-by: Simon Glass <sjg at chromium.org>