regulator: machine driver interface

This interface is for machine specific code and allows the creation of
voltage/current domains (with constraints) for each regulator. It can
provide regulator constraints that will prevent device damage through
overvoltage or over current caused by buggy client drivers. It also
allows the creation of a regulator tree whereby some regulators are
supplied by others (similar to a clock tree).
Signed-off-by: Liam Girdwood <lg@opensource.wolfsonmicro.com>
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

include/linux/regulator/machine.h

+/*
+ * machine.h -- SoC Regulator support, machine/board driver API.
+ *
+ * Copyright (C) 2007, 2008 Wolfson Microelectronics PLC.
+ *
+ * Author: Liam Girdwood <lg@opensource.wolfsonmicro.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Regulator Machine/Board Interface.
+ */
+
+#ifndef __LINUX_REGULATOR_MACHINE_H_
+#define __LINUX_REGULATOR_MACHINE_H_
+
+#include <linux/regulator/consumer.h>
+#include <linux/suspend.h>
+
+struct regulator;
+
+/*
+ * Regulator operation constraint flags. These flags are used to enable
+ * certain regulator operations and can be OR'ed together.
+ *
+ * VOLTAGE:  Regulator output voltage can be changed by software on this
+ *           board/machine.
+ * CURRENT:  Regulator output current can be changed by software on this
+ *           board/machine.
+ * MODE:     Regulator operating mode can be changed by software on this
+ *           board/machine.
+ * STATUS:   Regulator can be enabled and disabled.
+ * DRMS:     Dynamic Regulator Mode Switching is enabled for this regulator.
+ */
+
+#define REGULATOR_CHANGE_VOLTAGE	0x1
+#define REGULATOR_CHANGE_CURRENT	0x2
+#define REGULATOR_CHANGE_MODE		0x4
+#define REGULATOR_CHANGE_STATUS		0x8
+#define REGULATOR_CHANGE_DRMS		0x10
+
+/**
+ * struct regulator_state - regulator state during low power syatem states
+ *
+ * This describes a regulators state during a system wide low power state.
+ */
+struct regulator_state {
+	int uV;	/* suspend voltage */
+	unsigned int mode; /* suspend regulator operating mode */
+	int enabled; /* is regulator enabled in this suspend state */
+};
+
+/**
+ * struct regulation_constraints - regulator operating constraints.
+ *
+ * This struct describes regulator and board/machine specific constraints.
+ */
+struct regulation_constraints {
+
+	char *name;
+
+	/* voltage output range (inclusive) - for voltage control */
+	int min_uV;
+	int max_uV;
+
+	/* current output range (inclusive) - for current control */
+	int min_uA;
+	int max_uA;
+
+	/* valid regulator operating modes for this machine */
+	unsigned int valid_modes_mask;
+
+	/* valid operations for regulator on this machine */
+	unsigned int valid_ops_mask;
+
+	/* regulator input voltage - only if supply is another regulator */
+	int input_uV;
+
+	/* regulator suspend states for global PMIC STANDBY/HIBERNATE */
+	struct regulator_state state_disk;
+	struct regulator_state state_mem;
+	struct regulator_state state_standby;
+	suspend_state_t initial_state; /* suspend state to set at init */
+
+	/* constriant flags */
+	unsigned always_on:1;	/* regulator never off when system is on */
+	unsigned boot_on:1;	/* bootloader/firmware enabled regulator */
+	unsigned apply_uV:1;	/* apply uV constraint iff min == max */
+};
+
+int regulator_set_supply(const char *regulator, const char *regulator_supply);
+
+const char *regulator_get_supply(const char *regulator);
+
+int regulator_set_machine_constraints(const char *regulator,
+	struct regulation_constraints *constraints);
+
+int regulator_set_device_supply(const char *regulator, struct device *dev,
+				const char *supply);
+
+int regulator_suspend_prepare(suspend_state_t state);
+
+#endif