On Fri, 2008-06-27 at 06:28 +0800, Rafael J. Wysocki wrote:
> +
> +/**
> * pci_enable_wake - enable PCI device as wakeup event source
> * @dev: PCI device affected
> * @state: PCI state from which device will issue wakeup events
> @@ -1046,66 +1108,84 @@ int pci_set_pcie_reset_state(struct pci_
> * 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.
> - *
> - * -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.
> + * always require such platform hooks.
> + *
> + * 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;
>
> - /* 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;
>
> - status = call_platform_enable_wakeup(&dev->dev, enable);
> + if (enable && platform_pci_can_wakeup(dev)) {
> + error = platform_pci_sleep_wake(dev, true);
> + if (!error)
> + /*
> + * The platform claims to have handled the
> device and
> + * we have to trust it to avoid double wake-up
> events.
> + */
> + return 0;
> + }
>
> - /* 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;
> -
> - /* Check device's ability to generate PME# */
> - pci_read_config_word(dev,pm+PCI_PM_PMC,&value);
> -
> - 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 || pci_pme_capable(dev, pm, state)) {
> + pci_pme_active(dev, pm, enable);
> if (enable)
> - call_platform_enable_wakeup(&dev->dev, 0);
> - return enable ? -EINVAL : 0;
> + return 0;
> }
>
> - pci_read_config_word(dev, pm + PCI_PM_CTRL, &value);
> + if (!enable && platform_pci_can_wakeup(dev))
> + error = platform_pci_sleep_wake(dev, false);
>
> - /* Clear PME_Status by writing 1 to it and enable PME# */
> - value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
> + return error;
> +}
>
> - if (!enable)
> - value &= ~PCI_PM_CTRL_PME_ENABLE;
> +/**
> + * 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;
>
> - pci_write_config_word(dev, pm + PCI_PM_CTRL, value);
> + /* find PCI PM capability in list */
> + pm = pci_find_capability(dev, PCI_CAP_ID_PM);
> + if (!pm)
> + return;
> + /* Check device's ability to generate PME# */
> + pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
>
> - return 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;
> + }
> +
> + 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);
> + }
> }
It appears a lot of drivers will call device_init_wakeup(dev, 1)
regardless if userspace enable wakeup for the device. Will you fix the
drivers?
Thanks,
Shaohua
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