Re: [PATCH 2/7] ACPI / PM: Move device power state selection routine to device_pm.c

From: Rafael J. Wysocki
Date: Tue Nov 06 2012 - 07:58:42 EST


On Tuesday, November 06, 2012 12:56:07 PM Aaron Lu wrote:
> This patch doesn't apply...
>
> I'm trying on Linus' master branch, HEAD is v3.7-rc4, and I've merged
> your pm-qos branch on top of v3.7-rc4.

Well, it applies for me.

You can use the linux-next branch of my tree instead. It may contain
some fixes made after this patch had been sent.

Thanks,
Rafael


> On Mon, Oct 29, 2012 at 10:09:09AM +0100, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> >
> > The ACPI function for choosing device power state is now located
> > in drivers/acpi/sleep.c, but drivers/acpi/device_pm.c is a more
> > logical place for it, so move it there.
> >
> > However, instead of moving the function entirely, move its core only
> > under a different name and with a different list of arguments, so
> > that it is more flexible, and leave a wrapper around it in the
> > original location.
> >
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> > ---
> > drivers/acpi/device_pm.c | 107 +++++++++++++++++++++++++++++++++++++++++++++++
> > drivers/acpi/sleep.c | 88 +-------------------------------------
> > include/acpi/acpi_bus.h | 15 ++++++
> > 3 files changed, 124 insertions(+), 86 deletions(-)
> >
> > Index: linux/drivers/acpi/device_pm.c
> > ===================================================================
> > --- linux.orig/drivers/acpi/device_pm.c
> > +++ linux/drivers/acpi/device_pm.c
> > @@ -23,7 +23,9 @@
> > */
> >
> > #include <linux/device.h>
> > +#include <linux/export.h>
> > #include <linux/mutex.h>
> > +#include <linux/pm_qos.h>
> >
> > #include <acpi/acpi.h>
> > #include <acpi/acpi_bus.h>
> > @@ -89,3 +91,108 @@ acpi_status acpi_remove_pm_notifier(stru
> > mutex_unlock(&acpi_pm_notifier_lock);
> > return status;
> > }
> > +
> > +/**
> > + * acpi_device_power_state - Get preferred power state of ACPI device.
> > + * @dev: Device whose preferred target power state to return.
> > + * @adev: ACPI device node corresponding to @dev.
> > + * @target_state: System state to match the resultant device state.
> > + * @d_max_in: Deepest low-power state to take into consideration.
> > + * @d_min_p: Location to store the upper limit of the allowed states range.
> > + * Return value: Preferred power state of the device on success, -ENODEV
> > + * (if there's no 'struct acpi_device' for @dev) or -EINVAL on failure
> > + *
> > + * Find the lowest power (highest number) ACPI device power state that the
> > + * device can be in while the system is in the state represented by
> > + * @target_state. If @d_min_p is set, the highest power (lowest number) device
> > + * power state that @dev can be in for the given system sleep state is stored
> > + * at the location pointed to by it.
> > + *
> > + * Callers must ensure that @dev and @adev are valid pointers and that @adev
> > + * actually corresponds to @dev before using this function.
> > + */
> > +int acpi_device_power_state(struct device *dev, struct acpi_device *adev,
> > + u32 target_state, int d_max_in, int *d_min_p)
> > +{
> > + char acpi_method[] = "_SxD";
> > + unsigned long long d_min, d_max;
> > + bool wakeup = false;
> > +
> > + if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3)
> > + return -EINVAL;
> > +
> > + if (d_max_in > ACPI_STATE_D3_HOT) {
> > + enum pm_qos_flags_status stat;
> > +
> > + stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
> > + if (stat == PM_QOS_FLAGS_ALL)
> > + d_max_in = ACPI_STATE_D3_HOT;
> > + }
> > +
> > + acpi_method[2] = '0' + target_state;
> > + /*
> > + * If the sleep state is S0, the lowest limit from ACPI is D3,
> > + * but if the device has _S0W, we will use the value from _S0W
> > + * as the lowest limit from ACPI. Finally, we will constrain
> > + * the lowest limit with the specified one.
> > + */
> > + d_min = ACPI_STATE_D0;
> > + d_max = ACPI_STATE_D3;
> > +
> > + /*
> > + * If present, _SxD methods return the minimum D-state (highest power
> > + * state) we can use for the corresponding S-states. Otherwise, the
> > + * minimum D-state is D0 (ACPI 3.x).
> > + *
> > + * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
> > + * provided -- that's our fault recovery, we ignore retval.
> > + */
> > + if (target_state > ACPI_STATE_S0) {
> > + acpi_evaluate_integer(adev->handle, acpi_method, NULL, &d_min);
> > + wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
> > + && adev->wakeup.sleep_state >= target_state;
> > + } else if (dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) !=
> > + PM_QOS_FLAGS_NONE) {
> > + wakeup = adev->wakeup.flags.valid;
> > + }
> > +
> > + /*
> > + * If _PRW says we can wake up the system from the target sleep state,
> > + * the D-state returned by _SxD is sufficient for that (we assume a
> > + * wakeup-aware driver if wake is set). Still, if _SxW exists
> > + * (ACPI 3.x), it should return the maximum (lowest power) D-state that
> > + * can wake the system. _S0W may be valid, too.
> > + */
> > + if (wakeup) {
> > + acpi_status status;
> > +
> > + acpi_method[3] = 'W';
> > + status = acpi_evaluate_integer(adev->handle, acpi_method, NULL,
> > + &d_max);
> > + if (ACPI_FAILURE(status)) {
> > + if (target_state != ACPI_STATE_S0 ||
> > + status != AE_NOT_FOUND)
> > + d_max = d_min;
> > + } else if (d_max < d_min) {
> > + /* Warn the user of the broken DSDT */
> > + printk(KERN_WARNING "ACPI: Wrong value from %s\n",
> > + acpi_method);
> > + /* Sanitize it */
> > + d_min = d_max;
> > + }
> > + }
> > +
> > + if (d_max_in < d_min)
> > + return -EINVAL;
> > + if (d_min_p)
> > + *d_min_p = d_min;
> > + /* constrain d_max with specified lowest limit (max number) */
> > + if (d_max > d_max_in) {
> > + for (d_max = d_max_in; d_max > d_min; d_max--) {
> > + if (adev->power.states[d_max].flags.valid)
> > + break;
> > + }
> > + }
> > + return d_max;
> > +}
> > +EXPORT_SYMBOL_GPL(acpi_device_power_state);
> > Index: linux/drivers/acpi/sleep.c
> > ===================================================================
> > --- linux.orig/drivers/acpi/sleep.c
> > +++ linux/drivers/acpi/sleep.c
> > @@ -19,7 +19,6 @@
> > #include <linux/acpi.h>
> > #include <linux/module.h>
> > #include <linux/pm_runtime.h>
> > -#include <linux/pm_qos.h>
> >
> > #include <asm/io.h>
> >
> > @@ -706,101 +705,20 @@ int acpi_suspend(u32 acpi_state)
> > * Return value: Preferred power state of the device on success, -ENODEV
> > * (if there's no 'struct acpi_device' for @dev) or -EINVAL on failure
> > *
> > - * Find the lowest power (highest number) ACPI device power state that the
> > - * device can be in while the system is in the sleep state represented
> > - * by %acpi_target_sleep_state. If @d_min_p is set, the highest power (lowest
> > - * number) device power state that @dev can be in for the given system sleep
> > - * state is stored at the location pointed to by it.
> > - *
> > * The caller must ensure that @dev is valid before using this function.
> > */
> > int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
> > {
> > acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
> > struct acpi_device *adev;
> > - char acpi_method[] = "_SxD";
> > - unsigned long long d_min, d_max;
> > - bool wakeup = false;
> >
> > - if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3)
> > - return -EINVAL;
> > if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
> > - printk(KERN_DEBUG "ACPI handle has no context!\n");
> > + dev_dbg(dev, "ACPI handle without context in %s!\n", __func__);
> > return -ENODEV;
> > }
> > - if (d_max_in > ACPI_STATE_D3_HOT) {
> > - enum pm_qos_flags_status stat;
> > -
> > - stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
> > - if (stat == PM_QOS_FLAGS_ALL)
> > - d_max_in = ACPI_STATE_D3_HOT;
> > - }
> > -
> > - acpi_method[2] = '0' + acpi_target_sleep_state;
> > - /*
> > - * If the sleep state is S0, the lowest limit from ACPI is D3,
> > - * but if the device has _S0W, we will use the value from _S0W
> > - * as the lowest limit from ACPI. Finally, we will constrain
> > - * the lowest limit with the specified one.
> > - */
> > - d_min = ACPI_STATE_D0;
> > - d_max = ACPI_STATE_D3;
> >
> > - /*
> > - * If present, _SxD methods return the minimum D-state (highest power
> > - * state) we can use for the corresponding S-states. Otherwise, the
> > - * minimum D-state is D0 (ACPI 3.x).
> > - *
> > - * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
> > - * provided -- that's our fault recovery, we ignore retval.
> > - */
> > - if (acpi_target_sleep_state > ACPI_STATE_S0) {
> > - acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);
> > - wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
> > - && adev->wakeup.sleep_state >= acpi_target_sleep_state;
> > - } else if (dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) !=
> > - PM_QOS_FLAGS_NONE) {
> > - wakeup = adev->wakeup.flags.valid;
> > - }
> > -
> > - /*
> > - * If _PRW says we can wake up the system from the target sleep state,
> > - * the D-state returned by _SxD is sufficient for that (we assume a
> > - * wakeup-aware driver if wake is set). Still, if _SxW exists
> > - * (ACPI 3.x), it should return the maximum (lowest power) D-state that
> > - * can wake the system. _S0W may be valid, too.
> > - */
> > - if (wakeup) {
> > - acpi_status status;
> > -
> > - acpi_method[3] = 'W';
> > - status = acpi_evaluate_integer(handle, acpi_method, NULL,
> > - &d_max);
> > - if (ACPI_FAILURE(status)) {
> > - if (acpi_target_sleep_state != ACPI_STATE_S0 ||
> > - status != AE_NOT_FOUND)
> > - d_max = d_min;
> > - } else if (d_max < d_min) {
> > - /* Warn the user of the broken DSDT */
> > - printk(KERN_WARNING "ACPI: Wrong value from %s\n",
> > - acpi_method);
> > - /* Sanitize it */
> > - d_min = d_max;
> > - }
> > - }
> > -
> > - if (d_max_in < d_min)
> > - return -EINVAL;
> > - if (d_min_p)
> > - *d_min_p = d_min;
> > - /* constrain d_max with specified lowest limit (max number) */
> > - if (d_max > d_max_in) {
> > - for (d_max = d_max_in; d_max > d_min; d_max--) {
> > - if (adev->power.states[d_max].flags.valid)
> > - break;
> > - }
> > - }
> > - return d_max;
> > + return acpi_device_power_state(dev, adev, acpi_target_sleep_state,
> > + d_max_in, d_min_p);
> > }
> > EXPORT_SYMBOL(acpi_pm_device_sleep_state);
> > #endif /* CONFIG_PM */
> > Index: linux/include/acpi/acpi_bus.h
> > ===================================================================
> > --- linux.orig/include/acpi/acpi_bus.h
> > +++ linux/include/acpi/acpi_bus.h
> > @@ -419,6 +419,8 @@ acpi_status acpi_add_pm_notifier(struct
> > acpi_notify_handler handler, void *context);
> > acpi_status acpi_remove_pm_notifier(struct acpi_device *adev,
> > acpi_notify_handler handler);
> > +int acpi_device_power_state(struct device *dev, struct acpi_device *adev,
> > + u32 target_state, int d_max_in, int *d_min_p);
> > int acpi_pm_device_sleep_state(struct device *, int *, int);
> > #else
> > static inline acpi_status acpi_add_pm_notifier(struct acpi_device *adev,
> > @@ -432,12 +434,23 @@ static inline acpi_status acpi_remove_pm
> > {
> > return AE_SUPPORT;
> > }
> > -static inline int acpi_pm_device_sleep_state(struct device *d, int *p, int m)
> > +static inline int __acpi_device_power_state(int m, int *p)
> > {
> > if (p)
> > *p = ACPI_STATE_D0;
> > return (m >= ACPI_STATE_D0 && m <= ACPI_STATE_D3) ? m : ACPI_STATE_D0;
> > }
> > +static inline int acpi_device_power_state(struct device *dev,
> > + struct acpi_device *adev,
> > + u32 target_state, int d_max_in,
> > + int *d_min_p)
> > +{
> > + return __acpi_device_power_state(d_max_in, d_min_p);
> > +}
> > +static inline int acpi_pm_device_sleep_state(struct device *d, int *p, int m)
> > +{
> > + return __acpi_device_power_state(m, p);
> > +}
> > #endif
> >
> > #ifdef CONFIG_PM_RUNTIME
> >
> --
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--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
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