regulator/mfd: Support for the ROHM BD71847

This adds support for the BD71847 which touches both MFD and regulator.
There's a few other bits and pieces included as some dependency patches
had already been applied so would've required rebasing.

For example ROHM BD71837 and ROHM BD71847 Power management ICs have
regulators which provide multiple linear ranges. Ranges can be
selected by individual non contagious bit in vsel register. Add
regmap helper functions for selecting ranges.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

Don't give up voltage mapping if first range with suitable min/max uV
does not provide the wanted voltage.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

Add a helper function regulator_set_pull_down_regmap to allow regmap
based regulators to easily enable pull down.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

Add a helper function regulator_set_soft_start_regmap to allow regmap
based regulators to easily enable soft start.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

The handling of bypass_val_on that was added in
regulator_get_bypass_regmap is done unconditionally however
several drivers don't define a value for bypass_val_on. This
results in those drivers reporting bypass being enabled when
it is not. In regulator_set_bypass_regmap we use bypass_mask
if bypass_val_on is zero. This patch adds similar handling in
regulator_get_bypass_regmap.

Fixes: commit dd1a571daee7 ("regulator: helpers: Ensure bypass register field matches ON value")
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

When checking bypass state for a regulator, we check to see if any bits
in the bypass mask are set. For most cases this is fine because there is
typically, only a single bit used to determine if the regulator is in
bypass. However, for some regulators, such as LDO6 on AS3722, the bypass
state is indicate by a value rather than a single bit. Therefore, when
checking the bypass state, check that the bypass field matches the ON
value.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

Add helper function to set the state of active-discharge of
regulator using regmap. The HW regulator driver can directly
use this by providing the necessary information in the regulator
descriptor.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

The function name in kernel-doc for regulator_map_voltage_linear_range()
was wrong.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

This patch extends the regulator helpers to account for device that use
multiple bits for control when using regmap enable/disable/bypass ops.

The actual regulator helpers wrongly assume that the regulator control
is always performed using single bits, using in the regulator_desc
struct only two parameters *_reg and *_mask defining register and mask
for control.

This patch extends this struct and introduces the helpers to take into
account devices where control is performed using multiple bits and
specific multi-bit values are used for enabling/disabling/bypassing the
regulator.

Signed-off-by: Carlo Caione <carlo@caione.org>
Signed-off-by: Mark Brown <broonie@linaro.org>