regulator: mp8859: Implement set_current_limit()

The mp8859 implements support for current limiting, provide support for
configuring this via the driver. The datasheet recommends that if the
device has hit the current limit then any changes should be implemented
via a ramp so we do so in the driver.

Tested-by: Markus Reichl <m.reichl@fivetechno.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://msgid.link/r/20240225-regulator-mp8859-v1-8-68ee2c839ded@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: mp8859: Report slew rate

The MP8859 implements voltage changes at the rate of 1mV/us, tell the core
about this so that it can provide appropriate delays on voltage changes.

Tested-by: Markus Reichl <m.reichl@fivetechno.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://msgid.link/r/20240225-regulator-mp8859-v1-7-68ee2c839ded@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: mp8859: Support status and error readback

The MP8859 can report if it is in regulation and detect over temperature
conditions, report this information via the relevant regulator API
calls.

Tested-by: Markus Reichl <m.reichl@fivetechno.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://msgid.link/r/20240225-regulator-mp8859-v1-6-68ee2c839ded@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: mp8859: Support active discharge control

The MP8859 can actively discharge the output when disabled, add support for
controlling this feature.

Tested-by: Markus Reichl <m.reichl@fivetechno.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://msgid.link/r/20240225-regulator-mp8859-v1-5-68ee2c839ded@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: mp8859: Support mode operations

The MP8859 provides mode control, implement the relevant regulator API
operations.

Tested-by: Markus Reichl <m.reichl@fivetechno.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://msgid.link/r/20240225-regulator-mp8859-v1-4-68ee2c839ded@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: mp8859: Support enable control

The MP8859 provides a software enable control, support it in the
regulator driver.

Tested-by: Markus Reichl <m.reichl@fivetechno.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://msgid.link/r/20240225-regulator-mp8859-v1-3-68ee2c839ded@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: mp8859: Validate and log device identifier information

Ensure that we are talking to a device which reports the expected ID
register information and log the OTP and revision information for
diagnostic purposes.

Tested-by: Markus Reichl <m.reichl@fivetechno.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://msgid.link/r/20240225-regulator-mp8859-v1-2-68ee2c839ded@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: mp8859: Specify register accessibility and enable caching

Avoid needless accesses to the hardware by caching register values that
we know, marking status registers as volatile as appropriate.

Tested-by: Markus Reichl <m.reichl@fivetechno.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://msgid.link/r/20240225-regulator-mp8859-v1-1-68ee2c839ded@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Switch i2c drivers back to use .probe()

After commit b8a1a4cd5a98 ("i2c: Provide a temporary .probe_new()
call-back type"), all drivers being converted to .probe_new() and then
03c835f498b5 ("i2c: Switch .probe() to not take an id parameter") convert
back to (the new) .probe() to be able to eventually drop .probe_new() from
struct i2c_driver.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de
Link: https://lore.kernel.org/r/20230505220218.1239542-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org

regulator: Set PROBE_PREFER_ASYNCHRONOUS for drivers between 5.4 and 5.10

This follows on the change ("regulator: Set PROBE_PREFER_ASYNCHRONOUS
for drivers that existed in 4.14") but changes regulators didn't exist
in Linux 5.4 but did exist in Linux 5.10.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20230316125351.4.I01f21c98901641a009890590ddc1354c0f294e5e@changeid
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: mp8859: Mark OF related data as maybe unused

The driver can be compile tested with !CONFIG_OF making certain data
unused:

drivers/regulator/mp8859.c:132:34: error: ‘mp8859_dt_id’ defined but not used [-Werror=unused-const-variable=]

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230310214553.275450-3-krzysztof.kozlowski@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: use linear_ranges helper

Change the regulator helpers to use common linear_ranges code.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Link: https://lore.kernel.org/r/64f01d5e381b8631a271616b7790f9d5640974fb.1588944082.git.matti.vaittinen@fi.rohmeurope.com
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: mp8859: add supply entry

Add vin_supply to the regulator description to support a nice
regulator tree.

Signed-off-by: Markus Reichl <m.reichl@fivetechno.de>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/20200203110034.1448-1-m.reichl@fivetechno.de
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: mp8859: tidy up white space in probe

These two lines are indented an extra tab.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200110055252.rvelu4ysvoxsbmlg@kili.mountain
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: mp8859: add driver

The MP8859 from Monolithic Power Systems is a single output DC/DC
converter. The voltage can be controlled via I2C.

Signed-off-by: Markus Reichl <m.reichl@fivetechno.de>
Link: https://lore.kernel.org/r/20200106211633.2882-2-m.reichl@fivetechno.de
Signed-off-by: Mark Brown <broonie@kernel.org>