lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

PCI ACPI: Rework PCI handling of wake-up

Browse Source 
* Introduce function acpi_pm_device_sleep_wake() for enabling and
  disabling the system wake-up capability of devices that are power
  manageable by ACPI.

* Introduce function acpi_bus_can_wakeup() allowing other (dependent)
  subsystems to check if ACPI is able to enable the system wake-up
  capability of given device.

* Introduce callback .sleep_wake() in struct pci_platform_pm_ops and
  for the ACPI PCI 'driver' make it use acpi_pm_device_sleep_wake().

* Introduce callback .can_wakeup() in struct pci_platform_pm_ops and
  for the ACPI 'driver' make it use acpi_bus_can_wakeup().

* Move the PME# handlig code out of pci_enable_wake() and split it
  into two functions, pci_pme_capable() and pci_pme_active(),
  allowing the caller to check if given device is capable of
  generating PME# from given power state and to enable/disable the
  device's PME# functionality, respectively.

* Modify pci_enable_wake() to use the new ACPI callbacks and the new
  PME#-related functions.

* Drop the generic .platform_enable_wakeup() callback that is not
  used any more.

* Introduce device_set_wakeup_capable() that will set the
  power.can_wakeup flag of given device.

* Rework PCI device PM initialization so that, if given device is
  capable of generating wake-up events, either natively through the
  PME# mechanism, or with the help of the platform, its
  power.can_wakeup flag is set and its power.should_wakeup flag is
  unset as appropriate.

* Make ACPI set the power.can_wakeup flag for devices found to be
  wake-up capable by it.

* Make the ACPI wake-up code enable/disable GPEs for devices that
  have the wakeup.flags.prepared flag set (which means that their
  wake-up power has been enabled).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
Rafael J. Wysocki
2008-07-07 03:34:48 +02:00
committed by Jesse Barnes
parent 0af4b8c4fb
commit eb9d0fe40e
11 changed files with 208 additions and 116 deletions
Download Patch File Download Diff File Expand all files Collapse all files

169
drivers/pci/pci.c
View File

@@ -380,7 +380,8 @@ static struct pci_platform_pm_ops *pci_platform_pm;
int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
{
if (!ops->is_manageable || !ops->set_state || !ops->choose_state)
if (!ops->is_manageable || !ops->set_state || !ops->choose_state
|| !ops->sleep_wake || !ops->can_wakeup)
return -EINVAL;
pci_platform_pm = ops;
return 0;
@@ -403,6 +404,17 @@ static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
}
static inline bool platform_pci_can_wakeup(struct pci_dev *dev)
{
return pci_platform_pm ? pci_platform_pm->can_wakeup(dev) : false;
}
static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
{
return pci_platform_pm ?
pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
}
/**
* pci_raw_set_power_state - Use PCI PM registers to set the power state of
* given PCI device
@@ -1035,6 +1047,56 @@ int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
return pcibios_set_pcie_reset_state(dev, state);
}
/**
* pci_pme_capable - check the capability of PCI device to generate PME#
* @dev: PCI device to handle.
* @pm: PCI PM capability offset of the device.
* @state: PCI state from which device will issue PME#.
*/
static bool pci_pme_capable(struct pci_dev *dev, int pm, pci_power_t state)
{
u16 pmc;
if (!pm)
return false;
/* Check device's ability to generate PME# from given state */
pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
pmc &= PCI_PM_CAP_PME_MASK;
pmc >>= ffs(PCI_PM_CAP_PME_MASK) - 1; /* First bit of mask */
return !!(pmc & (1 << state));
}
/**
* pci_pme_active - enable or disable PCI device's PME# function
* @dev: PCI device to handle.
* @pm: PCI PM capability offset of the device.
* @enable: 'true' to enable PME# generation; 'false' to disable it.
*
* The caller must verify that the device is capable of generating PME# before
* calling this function with @enable equal to 'true'.
*/
static void pci_pme_active(struct pci_dev *dev, int pm, bool enable)
{
u16 pmcsr;
if (!pm)
return;
pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr);
/* Clear PME_Status by writing 1 to it and enable PME# */
pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
if (!enable)
pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
pci_write_config_word(dev, pm + PCI_PM_CTRL, pmcsr);
dev_printk(KERN_INFO, &dev->dev, "PME# %s\n",
enable ? "enabled" : "disabled");
}
/**
* pci_enable_wake - enable PCI device as wakeup event source
* @dev: PCI device affected
@@ -1046,66 +1108,83 @@ int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
* called automatically by this routine.
*
* Devices with legacy power management (no standard PCI PM capabilities)
* always require such platform hooks. Depending on the platform, devices
* supporting the standard PCI PME# signal may require such platform hooks;
* they always update bits in config space to allow PME# generation.
* always require such platform hooks.
*
* -EIO is returned if the device can't ever be a wakeup event source.
* -EINVAL is returned if the device can't generate wakeup events from
* the specified PCI state. Returns zero if the operation is successful.
* RETURN VALUE:
* 0 is returned on success
* -EINVAL is returned if device is not supposed to wake up the system
* Error code depending on the platform is returned if both the platform and
* the native mechanism fail to enable the generation of wake-up events
*/
int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
{
int pm;
int status;
u16 value;
int error = 0;
bool pme_done = false;
/* Note that drivers should verify device_may_wakeup(&dev->dev)
* before calling this function. Platform code should report
* errors when drivers try to enable wakeup on devices that
* can't issue wakeups, or on which wakeups were disabled by
* userspace updating the /sys/devices.../power/wakeup file.
if (!device_may_wakeup(&dev->dev))
return -EINVAL;
/*
* According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
* Anderson we should be doing PME# wake enable followed by ACPI wake
* enable. To disable wake-up we call the platform first, for symmetry.
*/
status = call_platform_enable_wakeup(&dev->dev, enable);
if (!enable && platform_pci_can_wakeup(dev))
error = platform_pci_sleep_wake(dev, false);
pm = pci_find_capability(dev, PCI_CAP_ID_PM);
if (!enable || pci_pme_capable(dev, pm, state)) {
pci_pme_active(dev, pm, enable);
pme_done = true;
}
if (enable && platform_pci_can_wakeup(dev))
error = platform_pci_sleep_wake(dev, true);
return pme_done ? 0 : error;
}
/**
* pci_pm_init - Initialize PM functions of given PCI device
* @dev: PCI device to handle.
*/
void pci_pm_init(struct pci_dev *dev)
{
int pm;
u16 pmc;
/* find PCI PM capability in list */
pm = pci_find_capability(dev, PCI_CAP_ID_PM);
/* If device doesn't support PM Capabilities, but caller wants to
* disable wake events, it's a NOP. Otherwise fail unless the
* platform hooks handled this legacy device already.
*/
if (!pm)
return enable ? status : 0;
return;
/* Check device's ability to generate PME# */
pci_read_config_word(dev,pm+PCI_PM_PMC,&value);
pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
value &= PCI_PM_CAP_PME_MASK;
value >>= ffs(PCI_PM_CAP_PME_MASK) - 1; /* First bit of mask */
/* Check if it can generate PME# from requested state. */
if (!value || !(value & (1 << state))) {
/* if it can't, revert what the platform hook changed,
* always reporting the base "EINVAL, can't PME#" error
*/
if (enable)
call_platform_enable_wakeup(&dev->dev, 0);
return enable ? -EINVAL : 0;
if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
pmc & PCI_PM_CAP_VER_MASK);
return;
}
pci_read_config_word(dev, pm + PCI_PM_CTRL, &value);
/* Clear PME_Status by writing 1 to it and enable PME# */
value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
if (!enable)
value &= ~PCI_PM_CTRL_PME_ENABLE;
pci_write_config_word(dev, pm + PCI_PM_CTRL, value);
return 0;
if (pmc & PCI_PM_CAP_PME_MASK) {
dev_printk(KERN_INFO, &dev->dev,
"PME# supported from%s%s%s%s%s\n",
(pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
(pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
(pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
(pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
(pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
/*
* Make device's PM flags reflect the wake-up capability, but
* let the user space enable it to wake up the system as needed.
*/
device_set_wakeup_capable(&dev->dev, true);
device_set_wakeup_enable(&dev->dev, false);
/* Disable the PME# generation functionality */
pci_pme_active(dev, pm, false);
}
}
int