regulator: da91xx: Allow caching of buck registers when no GPIO input control is...

André Svensson <andre.svensson@axis.com> says:

This series introduces a boolean DT property, dlg,no-gpio-control, for
the DA91xx regulators. Use this property to indicate that GPIO control
is not configured with the functions DVC/RELOAD/EN, allowing buck
registers to be cached.

The DA9121 driver checks dlg,no-gpio-control and updates regmap_config's
volatile_table if the property is present. Buck registers are removed
from the volatile_table if the property is present, enabling caching of
the registers, which removes I2C reads when performing an I2C write to
the buck registers.

Link: https://patch.msgid.link/20260320-no-gpio-control-v2-0-dbc938e462cb@axis.com
Signed-off-by: Mark Brown <broonie@kernel.org>