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-rw-r--r--Documentation/power/regulator/machine.txt140
-rw-r--r--Documentation/power/regulator/regulator.txt8
-rw-r--r--Documentation/power/s2ram.txt18
3 files changed, 88 insertions, 78 deletions
diff --git a/Documentation/power/regulator/machine.txt b/Documentation/power/regulator/machine.txt
index c9a35665cf7..ce3487d99ab 100644
--- a/Documentation/power/regulator/machine.txt
+++ b/Documentation/power/regulator/machine.txt
@@ -2,17 +2,8 @@ Regulator Machine Driver Interface
===================================
The regulator machine driver interface is intended for board/machine specific
-initialisation code to configure the regulator subsystem. Typical things that
-machine drivers would do are :-
+initialisation code to configure the regulator subsystem.
- 1. Regulator -> Device mapping.
- 2. Regulator supply configuration.
- 3. Power Domain constraint setting.
-
-
-
-1. Regulator -> device mapping
-==============================
Consider the following machine :-
Regulator-1 -+-> Regulator-2 --> [Consumer A @ 1.8 - 2.0V]
@@ -21,81 +12,82 @@ Consider the following machine :-
The drivers for consumers A & B must be mapped to the correct regulator in
order to control their power supply. This mapping can be achieved in machine
-initialisation code by calling :-
+initialisation code by creating a struct regulator_consumer_supply for
+each regulator.
+
+struct regulator_consumer_supply {
+ struct device *dev; /* consumer */
+ const char *supply; /* consumer supply - e.g. "vcc" */
+};
-int regulator_set_device_supply(const char *regulator, struct device *dev,
- const char *supply);
+e.g. for the machine above
-and is shown with the following code :-
+static struct regulator_consumer_supply regulator1_consumers[] = {
+{
+ .dev = &platform_consumerB_device.dev,
+ .supply = "Vcc",
+},};
-regulator_set_device_supply("Regulator-1", devB, "Vcc");
-regulator_set_device_supply("Regulator-2", devA, "Vcc");
+static struct regulator_consumer_supply regulator2_consumers[] = {
+{
+ .dev = &platform_consumerA_device.dev,
+ .supply = "Vcc",
+},};
This maps Regulator-1 to the 'Vcc' supply for Consumer B and maps Regulator-2
to the 'Vcc' supply for Consumer A.
-
-2. Regulator supply configuration.
-==================================
-Consider the following machine (again) :-
-
- Regulator-1 -+-> Regulator-2 --> [Consumer A @ 1.8 - 2.0V]
- |
- +-> [Consumer B @ 3.3V]
+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 regulator :-
+
+static struct regulator_init_data regulator1_data = {
+ .constraints = {
+ .min_uV = 3300000,
+ .max_uV = 3300000,
+ .valid_modes_mask = REGULATOR_MODE_NORMAL,
+ },
+ .num_consumer_supplies = ARRAY_SIZE(regulator1_consumers),
+ .consumer_supplies = regulator1_consumers,
+};
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 it's
-supply (Regulator-2).
-
-This relationship can be register with the core via :-
-
-int regulator_set_supply(const char *regulator, const char *regulator_supply);
-
-In this example we would use the following code :-
-
-regulator_set_supply("Regulator-2", "Regulator-1");
-
-Relationships can be queried by calling :-
-
-const char *regulator_get_supply(const char *regulator);
-
-
-3. Power Domain constraint setting.
-===================================
-Each power domain within a system has physical constraints on voltage and
-current. This must be defined in software so that the power domain is always
-operated within specifications.
-
-Consider the following machine (again) :-
-
- Regulator-1 -+-> Regulator-2 --> [Consumer A @ 1.8 - 2.0V]
- |
- +-> [Consumer B @ 3.3V]
-
-This gives us two regulators and two power domains:
-
- Domain 1: Regulator-2, Consumer B.
- Domain 2: Consumer A.
-
-Constraints can be registered by calling :-
-
-int regulator_set_platform_constraints(const char *regulator,
- struct regulation_constraints *constraints);
-
-The example is defined as follows :-
-
-struct regulation_constraints domain_1 = {
- .min_uV = 3300000,
- .max_uV = 3300000,
- .valid_modes_mask = REGULATOR_MODE_NORMAL,
+supply (Regulator-2). The supply regulator is set by the supply_regulator_dev
+field below:-
+
+static struct regulator_init_data regulator2_data = {
+ .supply_regulator_dev = &platform_regulator1_device.dev,
+ .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,
};
-struct regulation_constraints domain_2 = {
- .min_uV = 1800000,
- .max_uV = 2000000,
- .valid_ops_mask = REGULATOR_CHANGE_VOLTAGE,
- .valid_modes_mask = REGULATOR_MODE_NORMAL,
+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(&wm8350_regulator_devices[0]);
-regulator_set_platform_constraints("Regulator-1", &domain_1);
-regulator_set_platform_constraints("Regulator-2", &domain_2);
+/* register regulator 2 device */
+platform_device_register(&wm8350_regulator_devices[1]);
diff --git a/Documentation/power/regulator/regulator.txt b/Documentation/power/regulator/regulator.txt
index a6905014359..4200accb9bb 100644
--- a/Documentation/power/regulator/regulator.txt
+++ b/Documentation/power/regulator/regulator.txt
@@ -10,11 +10,11 @@ Registration
Drivers can register a regulator by calling :-
-struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
- void *reg_data);
+struct regulator_dev *regulator_register(struct device *dev,
+ struct regulator_desc *regulator_desc);
-This will register the regulators capabilities and operations the regulator
-core. The core does not touch reg_data (private to regulator driver).
+This will register the regulators capabilities and operations to the regulator
+core.
Regulators can be unregistered by calling :-
diff --git a/Documentation/power/s2ram.txt b/Documentation/power/s2ram.txt
index b05f512130e..2ebdc6091ce 100644
--- a/Documentation/power/s2ram.txt
+++ b/Documentation/power/s2ram.txt
@@ -54,3 +54,21 @@ used to run with "radeonfb" (it's an ATI Radeon mobility). It turns out
that "radeonfb" simply cannot resume that device - it tries to set the
PLL's, and it just _hangs_. Using the regular VGA console and letting X
resume it instead works fine.
+
+NOTE
+====
+pm_trace uses the system's Real Time Clock (RTC) to save the magic number.
+Reason for this is that the RTC is the only reliably available piece of
+hardware during resume operations where a value can be set that will
+survive a reboot.
+
+Consequence is that after a resume (even if it is successful) your system
+clock will have a value corresponding to the magic mumber instead of the
+correct date/time! It is therefore advisable to use a program like ntp-date
+or rdate to reset the correct date/time from an external time source when
+using this trace option.
+
+As the clock keeps ticking it is also essential that the reboot is done
+quickly after the resume failure. The trace option does not use the seconds
+or the low order bits of the minutes of the RTC, but a too long delay will
+corrupt the magic value.