regulator: Use bitfield values for range selectors

Right now the regulator helpers expect raw register values for the range
selectors. This is different from the voltage selectors, which are
normalized as bitfield values. This leads to a bit of confusion. Also,
raw values are harder to copy from datasheets or match up with them,
as datasheets will typically have bitfield values.

Make the helpers expect bitfield values, and convert existing users. The
field in regulator_desc is renamed to |linear_range_selectors_bitfield|.
This is intended to cause drivers added in the same merge window and
out-of-tree drivers using the incorrect variable and values to break,
preventing incorrect values being used on actual hardware and potentially
producing magic smoke.

Also include bitops.h explicitly for ffs(), and reorder the header include
statements. While at it, also replace module.h with export.h, since the
only use is EXPORT_SYMBOL_GPL.

Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20230714081408.274567-1-wenst@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: rohm-regulator: add helper for restricted voltage setting

Few ROHM PMICs have regulators where voltage setting can be done only
when regulator is disabled. Add helper for those PMICs.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Link: https://lore.kernel.org/r/6f51871e9fea611d133b5dd2560f4a7ee1ede9cd.1637233864.git.matti.vaittinen@fi.rohmeurope.com
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: rohm-regulator: Support SNVS HW state.

The ROHM BD71815 supports setting voltage levels/regulator status
for HW-states "RUN", "SUSPEND", "LPSR" and "SNVS". Add DT parsing
helper also for SNVS state.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

regulator: rohm-regulator: linear voltage support

The helper for obtaining HW-state based DVS voltage levels currently only
works for regulators using linear-ranges. Extend support to regulators with
simple linear mappings and add also proper error path if pickable-ranges
regulators call this.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

regulator: bd718x7, bd71828, Fix dvs voltage levels

The ROHM BD718x7 and BD71828 drivers support setting HW state
specific voltages from device-tree. This is used also by various
in-tree DTS files.

These drivers do incorrectly try to compose bit-map using enum
values. By a chance this works for first two valid levels having
values 1 and 2 - but setting values for the rest of the levels
do indicate capability of setting values for first levels as
well. Luckily the regulators which support setting values for
SUSPEND/LPSR do usually also support setting values for RUN
and IDLE too - thus this has not been such a fatal issue.

Fix this by defining the old enum values as bits and fixing the
parsing code. This allows keeping existing IC specific drivers
intact and only slightly changing the rohm-regulator.c

Fixes: 21b72156ede8b ("regulator: bd718x7: Split driver to common and bd718x7 specific parts")
Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210212080023.GA880728@localhost.localdomain
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: bd718x7: Split driver to common and bd718x7 specific parts

Few ROHM PMICs allow setting the voltage states for different system states
like RUN, IDLE, SUSPEND and LPSR. States are then changed via SoC specific
mechanisms. bd718x7 driver implemented device-tree parsing functions for
these state specific voltages. The parsing functions can be re-used by
other ROHM chip drivers like bd71828. Split the generic functions from
bd718x7-regulator.c to rohm-regulator.c and export them for other modules
to use.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>