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+==================================
+Regulator Machine Driver Interface
+==================================
+
+The regulator machine driver interface is intended for board/machine specific
+initialisation code to configure the regulator subsystem.
+
+Consider the following machine::
+
+ Regulator-1 -+-> Regulator-2 --> [Consumer A @ 1.8 - 2.0V]
+ |
+ +-> [Consumer B @ 3.3V]
+
+The drivers for consumers A & B must be mapped to the correct regulator in
+order to control their power supplies. This mapping can be achieved in machine
+initialisation code by creating a struct regulator_consumer_supply for
+each regulator::
+
+ struct regulator_consumer_supply {
+ const char *dev_name; /* consumer dev_name() */
+ const char *supply; /* consumer supply - e.g. "vcc" */
+ };
+
+e.g. for the machine above::
+
+ static struct regulator_consumer_supply regulator1_consumers[] = {
+ REGULATOR_SUPPLY("Vcc", "consumer B"),
+ };
+
+ static struct regulator_consumer_supply regulator2_consumers[] = {
+ REGULATOR_SUPPLY("Vcc", "consumer A"),
+ };
+
+This maps Regulator-1 to the 'Vcc' supply for Consumer B and maps Regulator-2
+to the 'Vcc' supply for Consumer A.
+
+Constraints can now be registered by defining a struct regulator_init_data
+for each regulator power domain. This structure also maps the consumers
+to their supply regulators::
+
+ static struct regulator_init_data regulator1_data = {
+ .constraints = {
+ .name = "Regulator-1",
+ .min_uV = 3300000,
+ .max_uV = 3300000,
+ .valid_modes_mask = REGULATOR_MODE_NORMAL,
+ },
+ .num_consumer_supplies = ARRAY_SIZE(regulator1_consumers),
+ .consumer_supplies = regulator1_consumers,
+ };
+
+The name field should be set to something that is usefully descriptive
+for the board for configuration of supplies for other regulators and
+for use in logging and other diagnostic output. Normally the name
+used for the supply rail in the schematic is a good choice. If no
+name is provided then the subsystem will choose one.
+
+Regulator-1 supplies power to Regulator-2. This relationship must be registered
+with the core so that Regulator-1 is also enabled when Consumer A enables its
+supply (Regulator-2). The supply regulator is set by the supply_regulator
+field below and co::
+
+ static struct regulator_init_data regulator2_data = {
+ .supply_regulator = "Regulator-1",
+ .constraints = {
+ .min_uV = 1800000,
+ .max_uV = 2000000,
+ .valid_ops_mask = REGULATOR_CHANGE_VOLTAGE,
+ .valid_modes_mask = REGULATOR_MODE_NORMAL,
+ },
+ .num_consumer_supplies = ARRAY_SIZE(regulator2_consumers),
+ .consumer_supplies = regulator2_consumers,
+ };
+
+Finally the regulator devices must be registered in the usual manner::
+
+ static struct platform_device regulator_devices[] = {
+ {
+ .name = "regulator",
+ .id = DCDC_1,
+ .dev = {
+ .platform_data = &regulator1_data,
+ },
+ },
+ {
+ .name = "regulator",
+ .id = DCDC_2,
+ .dev = {
+ .platform_data = &regulator2_data,
+ },
+ },
+ };
+ /* register regulator 1 device */
+ platform_device_register(&regulator_devices[0]);
+
+ /* register regulator 2 device */
+ platform_device_register(&regulator_devices[1]);