PCI PM: Add function for checking PME status of devices

Add function pci_check_pme_status() that will check the PME status
bit of given device and clear it along with the PME enable bit.  It
will be necessary for PCI run-time power management.

Based on a patch from Shaohua Li <shaohua.li@intel.com>

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 2010-02-17 23:36:58 +01:00 коммит произвёл Jesse Barnes
Родитель 6d3be84aab
Коммит 58ff463396
2 изменённых файлов: 36 добавлений и 0 удалений

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@ -1194,6 +1194,41 @@ int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
return pcibios_set_pcie_reset_state(dev, state);
}
/**
* pci_check_pme_status - Check if given device has generated PME.
* @dev: Device to check.
*
* Check the PME status of the device and if set, clear it and clear PME enable
* (if set). Return 'true' if PME status and PME enable were both set or
* 'false' otherwise.
*/
bool pci_check_pme_status(struct pci_dev *dev)
{
int pmcsr_pos;
u16 pmcsr;
bool ret = false;
if (!dev->pm_cap)
return false;
pmcsr_pos = dev->pm_cap + PCI_PM_CTRL;
pci_read_config_word(dev, pmcsr_pos, &pmcsr);
if (!(pmcsr & PCI_PM_CTRL_PME_STATUS))
return false;
/* Clear PME status. */
pmcsr |= PCI_PM_CTRL_PME_STATUS;
if (pmcsr & PCI_PM_CTRL_PME_ENABLE) {
/* Disable PME to avoid interrupt flood. */
pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
ret = true;
}
pci_write_config_word(dev, pmcsr_pos, pmcsr);
return ret;
}
/**
* pci_pme_capable - check the capability of PCI device to generate PME#
* @dev: PCI device to handle.

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@ -49,6 +49,7 @@ struct pci_platform_pm_ops {
extern int pci_set_platform_pm(struct pci_platform_pm_ops *ops);
extern void pci_update_current_state(struct pci_dev *dev, pci_power_t state);
extern void pci_disable_enabled_device(struct pci_dev *dev);
extern bool pci_check_pme_status(struct pci_dev *dev);
extern void pci_pm_init(struct pci_dev *dev);
extern void platform_pci_wakeup_init(struct pci_dev *dev);
extern void pci_allocate_cap_save_buffers(struct pci_dev *dev);