Re: [PATCH 0/13] Updated V4 - Regulator Framework

Liam Girdwood
2008-05-11T14:39:35Z

On Fri, 2008-05-09 at 20:44 +0100, Liam Girdwood wrote:
> On Fri, 2008-05-09 at 06:37 +0200, Harald Welte wrote:
> > On Thu, May 08, 2008 at 09:51:27PM +0100, Liam Girdwood wrote:
> > > > Do you think it would be worth to export something like this in the
> > > > generic API, too? It's probably quite hard, since there are devices
> > > > that actually use the PCF506xx STANDBY state during suspend-to-ram, but
> > > > other devices leave the PCF506xx in the ON state and just disable the
> > > > individual regulators using I2C register writes.
> > >

I've now finished the first draft of the system wide suspend state
changes. This fits in well for WM8350 suspend configuration, could you
give it a quick look over wrt pcf506xx family.

Changes :-

o ﻿regulator_suspend_prepare() added to set all the PMIC regulator
states before the system enters suspend. This would be called by your
platform/machine specific suspend code.
o added sysfs entries for mem, disk and standby regulator config.
o added fields for each suspend state in struct ﻿regulation_constraints
to define each regulator suspend state.
o added operations to struct ﻿regulator_ops to support regulator
suspend state configuration in regulator drivers.

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index f698f84..db259e8 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -17,11 +17,12 @@
#include <linux/device.h>
#include <linux/err.h>
#include <linux/mutex.h>
+#include <linux/suspend.h>
#include <linux/regulator/consumer.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>

-#define REGULATOR_VERSION "0.4"
+#define REGULATOR_VERSION "0.5"

static DEFINE_MUTEX(regulator_list_mutex);
static LIST_HEAD(regulator_list);
@@ -358,6 +359,126 @@ static ssize_t regulator_type_show(struct device *dev,
return sprintf(buf, "unknown\n");
}

+static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct regulator_dev *rdev = to_rdev(dev);
+
+ if (!rdev->constraints)
+ return sprintf(buf, "not defined\n");
+ return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
+}
+
+static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct regulator_dev *rdev = to_rdev(dev);
+
+ if (!rdev->constraints)
+ return sprintf(buf, "not defined\n");
+ return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
+}
+
+static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct regulator_dev *rdev = to_rdev(dev);
+
+ if (!rdev->constraints)
+ return sprintf(buf, "not defined\n");
+ return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
+}
+
+static ssize_t suspend_opmode_show(struct regulator_dev *rdev,
+ unsigned int mode, char *buf)
+{
+ switch (mode) {
+ case REGULATOR_MODE_FAST:
+ return sprintf(buf, "fast\n");
+ case REGULATOR_MODE_NORMAL:
+ return sprintf(buf, "normal\n");
+ case REGULATOR_MODE_IDLE:
+ return sprintf(buf, "idle\n");
+ case REGULATOR_MODE_STANDBY:
+ return sprintf(buf, "standby\n");
+ }
+ return sprintf(buf, "unknown\n");
+}
+
+static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct regulator_dev *rdev = to_rdev(dev);
+
+ if (!rdev->constraints)
+ return sprintf(buf, "not defined\n");
+ return suspend_opmode_show(rdev,
+ rdev->constraints->state_mem.mode, buf);
+}
+
+static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct regulator_dev *rdev = to_rdev(dev);
+
+ if (!rdev->constraints)
+ return sprintf(buf, "not defined\n");
+ return suspend_opmode_show(rdev,
+ rdev->constraints->state_disk.mode, buf);
+}
+
+static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct regulator_dev *rdev = to_rdev(dev);
+
+ if (!rdev->constraints)
+ return sprintf(buf, "not defined\n");
+ return suspend_opmode_show(rdev,
+ rdev->constraints->state_standby.mode, buf);
+}
+
+static ssize_t regulator_suspend_mem_state_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct regulator_dev *rdev = to_rdev(dev);
+
+ if (!rdev->constraints)
+ return sprintf(buf, "not defined\n");
+
+ if (rdev->constraints->state_mem.enabled)
+ return sprintf(buf, "enabled\n");
+ else
+ return sprintf(buf, "disabled\n");
+}
+
+static ssize_t regulator_suspend_disk_state_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct regulator_dev *rdev = to_rdev(dev);
+
+ if (!rdev->constraints)
+ return sprintf(buf, "not defined\n");
+
+ if (rdev->constraints->state_disk.enabled)
+ return sprintf(buf, "enabled\n");
+ else
+ return sprintf(buf, "disabled\n");
+}
+
+static ssize_t regulator_suspend_standby_state_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct regulator_dev *rdev = to_rdev(dev);
+
+ if (!rdev->constraints)
+ return sprintf(buf, "not defined\n");
+
+ if (rdev->constraints->state_standby.enabled)
+ return sprintf(buf, "enabled\n");
+ else
+ return sprintf(buf, "disabled\n");
+}
static struct device_attribute regulator_dev_attrs[] = {
__ATTR(microvolts, 0444, regulator_uV_show, NULL),
__ATTR(microamps, 0444, regulator_uA_show, NULL),
@@ -370,6 +491,24 @@ static struct device_attribute regulator_dev_attrs[] = {
__ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL),
__ATTR(num_users, 0444, regulator_num_users_show, NULL),
__ATTR(type, 0444, regulator_type_show, NULL),
+ __ATTR(suspend_mem_microvolts, 0444,
+ regulator_suspend_mem_uV_show, NULL),
+ __ATTR(suspend_disk_microvolts, 0444,
+ regulator_suspend_disk_uV_show, NULL),
+ __ATTR(suspend_standby_microvolts, 0444,
+ regulator_suspend_standby_uV_show, NULL),
+ __ATTR(suspend_mem_mode, 0444,
+ regulator_suspend_mem_mode_show, NULL),
+ __ATTR(suspend_disk_mode, 0444,
+ regulator_suspend_disk_mode_show, NULL),
+ __ATTR(suspend_standby_mode, 0444,
+ regulator_suspend_standby_mode_show, NULL),
+ __ATTR(suspend_mem_state, 0444,
+ regulator_suspend_mem_state_show, NULL),
+ __ATTR(suspend_disk_state, 0444,
+ regulator_suspend_disk_state_show, NULL),
+ __ATTR(suspend_standby_state, 0444,
+ regulator_suspend_standby_state_show, NULL),
__ATTR_NULL,
};

@@ -425,6 +564,65 @@ static void drms_uA_update(struct regulator_dev *rdev)
rdev->desc->ops->set_mode(rdev, mode);
}

+static int suspend_set_state(struct regulator_dev *rdev,
+ struct regulator_state *rstate)
+{
+ int ret = 0;
+
+ /* enable & disable are mandatory for suspend control */
+ if (!rdev->desc->ops->set_suspend_enable ||
+ !rdev->desc->ops->set_suspend_disable)
+ return -EINVAL;
+
+ if (rstate->enabled)
+ ret = rdev->desc->ops->set_suspend_enable(rdev);
+ else
+ ret = rdev->desc->ops->set_suspend_disable(rdev);
+ if (ret < 0) {
+ printk(KERN_ERR "%s: failed to enabled/disable\n", __func__);
+ return ret;
+ }
+
+ if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
+ ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
+ if (ret < 0) {
+ printk(KERN_ERR "%s: failed to set voltage\n",
+ __func__);
+ return ret;
+ }
+ }
+
+ if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
+ ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
+ if (ret < 0) {
+ printk(KERN_ERR "%s: failed to set mode\n", __func__);
+ return ret;
+ }
+ }
+ return ret;
+}
+
+/* locks held by caller */
+static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
+{
+ if (!rdev->constraints)
+ return -EINVAL;
+
+ switch (state) {
+ case PM_SUSPEND_STANDBY:
+ return suspend_set_state(rdev,
+ &rdev->constraints->state_standby);
+ case PM_SUSPEND_MEM:
+ return suspend_set_state(rdev,
+ &rdev->constraints->state_mem);
+ case PM_SUSPEND_MAX:
+ return suspend_set_state(rdev,
+ &rdev->constraints->state_disk);
+ default:
+ return -EINVAL;
+ }
+}
+
static void print_constraints(struct regulator_dev *rdev)
{
struct regulation_constraints *constraints = rdev->constraints;
@@ -923,7 +1121,7 @@ int regulator_get_voltage(struct regulator *regulator)
EXPORT_SYMBOL_GPL(regulator_get_voltage);

/**
- * regulator_set_current_limit - set regulator output current for a current sink
+ * regulator_set_current_limit - set regulator output current limit
* @regulator: regulator source
* @min_uA: Minimuum supported current in uA
* @max_uA: Maximum supported current in uA
@@ -1567,6 +1765,10 @@ found:
if (rdev->constraints->boot_on)
rdev->use_count = 1;

+ /* do we need to setup our suspend state */
+ if (constraints->initial_state)
+ ret = suspend_prepare(rdev, constraints->initial_state);
+
print_constraints(rdev);
mutex_unlock(&rdev->mutex);

@@ -1612,6 +1814,41 @@ int regulator_set_device_supply(const char *regulator, struct device *dev,
EXPORT_SYMBOL_GPL(regulator_set_device_supply);

/**
+ * regulator_suspend_prepare: prepare regulators for system wide suspend
+ * @state: system suspend state
+ *
+ * Configure each regulator with it's suspend operating parameters for state.
+ * This will usually be called by machine suspend code prior to supending.
+ */
+int regulator_suspend_prepare(suspend_state_t state)
+{
+ struct regulator_dev *rdev;
+ int ret = 0;
+
+ /* ON is handled by regulator active state */
+ if (state == PM_SUSPEND_ON)
+ return -EINVAL;
+
+ mutex_lock(&regulator_list_mutex);
+ list_for_each_entry(rdev, &regulator_list, list) {
+
+ mutex_lock(&rdev->mutex);
+ ret = suspend_prepare(rdev, state);
+ mutex_unlock(&rdev->mutex);
+
+ if (ret < 0) {
+ printk(KERN_ERR "%s: failed to prepare %s\n",
+ __func__, rdev->desc->name);
+ goto out;
+ }
+ }
+out:
+ mutex_unlock(&regulator_list_mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
+
+/**
* rdev_get_drvdata - get rdev regulator driver data
* @regulator: regulator
*
diff --git a/include/linux/regulator/driver.h b/include/linux/regulator/driver.h
index 1c02362..1d712c7 100644
--- a/include/linux/regulator/driver.h
+++ b/include/linux/regulator/driver.h
@@ -49,6 +49,19 @@ struct regulator_ops {
/* get most efficient regulator operating mode for load */
unsigned int (*get_optimum_mode) (struct regulator_dev *, int input_uV,
int output_uV, int load_uA);
+
+ /* the operations below are for configuration of regulator state when
+ * it's parent PMIC enters a global STANBY/HIBERNATE state */
+
+ /* set regulator suspend voltage */
+ int (*set_suspend_voltage) (struct regulator_dev *, int uV);
+
+ /* enable/disable regulator in suspend state */
+ int (*set_suspend_enable) (struct regulator_dev *);
+ int (*set_suspend_disable) (struct regulator_dev *);
+
+ /* set regulator suspend operating mode (defined in regulator.h) */
+ int (*set_suspend_mode) (struct regulator_dev *, unsigned int mode);
};

/*
diff --git a/include/linux/regulator/machine.h b/include/linux/regulator/machine.h
index 69b492c..d3479a8 100644
--- a/include/linux/regulator/machine.h
+++ b/include/linux/regulator/machine.h
@@ -39,6 +39,18 @@ struct regulator;
#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.
*
@@ -65,6 +77,12 @@ struct regulation_constraints {
/* 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 */
u32 always_on:1; /* regulator never off when system is on */
u32 boot_on:1; /* bootloader/firmware enabled regulator */
@@ -81,4 +99,6 @@ int regulator_set_machine_constraints(const char *regulator,
int regulator_set_device_supply(const char *regulator, struct device *dev,
const char *supply);

+int regulator_suspend_prepare(suspend_state_t state);
+
#endif
diff --git a/Documentation/ABI/testing/sysfs-class-regulator b/Documentation/ABI/testing/sysfs-class-regulator
index 4655927..79a4a75 100644
--- a/Documentation/ABI/testing/sysfs-class-regulator
+++ b/Documentation/ABI/testing/sysfs-class-regulator
@@ -185,3 +185,131 @@ Contact: Liam Girdwood <lg@opensource.wolfsonmicro.com>
Description:
Some regulator directories will contain a link called parent.
This points to the parent or supply regulator if one exists.
+
+What: /sys/class/regulator/.../suspend_mem_microvolts
+Date: May 2008
+KernelVersion: 2.6.26
+Contact: Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+ Each regulator directory will contain a field called
+ suspend_mem_microvolts. This holds the regulator output
+ voltage setting for this domain measured in microvolts when
+ the system is suspended to memory.
+
+ NOTE: this will return the string 'not defined' if
+ the power domain has no suspend to memory voltage defined by
+ platform code.
+
+What: /sys/class/regulator/.../suspend_disk_microvolts
+Date: May 2008
+KernelVersion: 2.6.26
+Contact: Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+ Each regulator directory will contain a field called
+ suspend_disk_microvolts. This holds the regulator output
+ voltage setting for this domain measured in microvolts when
+ the system is suspended to disk.
+
+ NOTE: this will return the string 'not defined' if
+ the power domain has no suspend to disk voltage defined by
+ platform code.
+
+What: /sys/class/regulator/.../suspend_standby_microvolts
+Date: May 2008
+KernelVersion: 2.6.26
+Contact: Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+ Each regulator directory will contain a field called
+ suspend_standby_microvolts. This holds the regulator output
+ voltage setting for this domain measured in microvolts when
+ the system is suspended to standby.
+
+ NOTE: this will return the string 'not defined' if
+ the power domain has no suspend to standby voltage defined by
+ platform code.
+
+What: /sys/class/regulator/.../suspend_mem_mode
+Date: May 2008
+KernelVersion: 2.6.26
+Contact: Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+ Each regulator directory will contain a field called
+ suspend_mem_mode. This holds the regulator operating mode
+ setting for this domain when the system is suspended to
+ memory.
+
+ NOTE: this will return the string 'not defined' if
+ the power domain has no suspend to memory mode defined by
+ platform code.
+
+What: /sys/class/regulator/.../suspend_disk_mode
+Date: May 2008
+KernelVersion: 2.6.26
+Contact: Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+ Each regulator directory will contain a field called
+ suspend_disk_mode. This holds the regulator operating mode
+ setting for this domain when the system is suspended to disk.
+
+ NOTE: this will return the string 'not defined' if
+ the power domain has no suspend to disk mode defined by
+ platform code.
+
+What: /sys/class/regulator/.../suspend_standby_mode
+Date: May 2008
+KernelVersion: 2.6.26
+Contact: Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+ Each regulator directory will contain a field called
+ suspend_standby_mode. This holds the regulator operating mode
+ setting for this domain when the system is suspended to
+ standby.
+
+ NOTE: this will return the string 'not defined' if
+ the power domain has no suspend to standby mode defined by
+ platform code.
+
+What: /sys/class/regulator/.../suspend_mem_state
+Date: May 2008
+KernelVersion: 2.6.26
+Contact: Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+ Each regulator directory will contain a field called
+ suspend_mem_state. This holds the regulator operating state
+ when suspended to memory.
+
+ This will be one of the following strings:
+
+ 'enabled'
+ 'disabled'
+ 'not defined'
+
+What: /sys/class/regulator/.../suspend_disk_state
+Date: May 2008
+KernelVersion: 2.6.26
+Contact: Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+ Each regulator directory will contain a field called
+ suspend_disk_state. This holds the regulator operating state
+ when suspended to disk.
+
+ This will be one of the following strings:
+
+ 'enabled'
+ 'disabled'
+ 'not defined'
+
+What: /sys/class/regulator/.../suspend_standby_state
+Date: May 2008
+KernelVersion: 2.6.26
+Contact: Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+ Each regulator directory will contain a field called
+ suspend_standby_state. This holds the regulator operating
+ state when suspended to standby.
+
+ This will be one of the following strings:
+
+ 'enabled'
+ 'disabled'
+ 'not defined'