diff options
Diffstat (limited to 'drivers/pci/pci.c')
| -rw-r--r-- | drivers/pci/pci.c | 169 |
1 files changed, 124 insertions, 45 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 20e28077b96..a6b1b6f96ab 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -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 @@ -1036,6 +1048,56 @@ int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state 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 * @state: PCI state from which device will issue wakeup events @@ -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; - - /* 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. - */ + int error = 0; + bool pme_done = false; - status = call_platform_enable_wakeup(&dev->dev, enable); - - /* find PCI PM capability in list */ - pm = pci_find_capability(dev, PCI_CAP_ID_PM); + if (!device_may_wakeup(&dev->dev)) + return -EINVAL; - /* 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. + /* + * 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. */ - if (!pm) - return enable ? status : 0; - /* Check device's ability to generate PME# */ - pci_read_config_word(dev,pm+PCI_PM_PMC,&value); + if (!enable && platform_pci_can_wakeup(dev)) + error = platform_pci_sleep_wake(dev, false); - 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; + 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; } - pci_read_config_word(dev, pm + PCI_PM_CTRL, &value); + if (enable && platform_pci_can_wakeup(dev)) + error = platform_pci_sleep_wake(dev, true); - /* Clear PME_Status by writing 1 to it and enable PME# */ - value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE; + return pme_done ? 0 : 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); + } } int |