From 76cde7e495904064d612cf3eb4bf6d9e76ff8191 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 1 Sep 2014 13:49:16 +0200 Subject: PCI / PM: Make PCIe PME interrupts wake up from suspend-to-idle To make PCIe PME interrupts wake up the system from suspend to idle, make the PME driver use enable_irq_wake() on the IRQ during system suspend (if there are any wakeup devices below the given PCIe port) without disabling PME interrupts. This way, an interrupt will still trigger if a wakeup event happens and the system will be woken up (or system suspend in progress will be aborted) by means of the new mechanics introduced previously. This change allows Wake-on-LAN to be used for wakeup from suspend-to-idle on my MSI Wind tesbed netbook. Signed-off-by: Rafael J. Wysocki --- drivers/pci/pcie/pme.c | 61 +++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 51 insertions(+), 10 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/pcie/pme.c b/drivers/pci/pcie/pme.c index 82e06a86cd77..a9f9c46e5022 100644 --- a/drivers/pci/pcie/pme.c +++ b/drivers/pci/pcie/pme.c @@ -41,11 +41,17 @@ static int __init pcie_pme_setup(char *str) } __setup("pcie_pme=", pcie_pme_setup); +enum pme_suspend_level { + PME_SUSPEND_NONE = 0, + PME_SUSPEND_WAKEUP, + PME_SUSPEND_NOIRQ, +}; + struct pcie_pme_service_data { spinlock_t lock; struct pcie_device *srv; struct work_struct work; - bool noirq; /* Don't enable the PME interrupt used by this service. */ + enum pme_suspend_level suspend_level; }; /** @@ -223,7 +229,7 @@ static void pcie_pme_work_fn(struct work_struct *work) spin_lock_irq(&data->lock); for (;;) { - if (data->noirq) + if (data->suspend_level != PME_SUSPEND_NONE) break; pcie_capability_read_dword(port, PCI_EXP_RTSTA, &rtsta); @@ -250,7 +256,7 @@ static void pcie_pme_work_fn(struct work_struct *work) spin_lock_irq(&data->lock); } - if (!data->noirq) + if (data->suspend_level == PME_SUSPEND_NONE) pcie_pme_interrupt_enable(port, true); spin_unlock_irq(&data->lock); @@ -367,6 +373,21 @@ static int pcie_pme_probe(struct pcie_device *srv) return ret; } +static bool pcie_pme_check_wakeup(struct pci_bus *bus) +{ + struct pci_dev *dev; + + if (!bus) + return false; + + list_for_each_entry(dev, &bus->devices, bus_list) + if (device_may_wakeup(&dev->dev) + || pcie_pme_check_wakeup(dev->subordinate)) + return true; + + return false; +} + /** * pcie_pme_suspend - Suspend PCIe PME service device. * @srv: PCIe service device to suspend. @@ -375,11 +396,26 @@ static int pcie_pme_suspend(struct pcie_device *srv) { struct pcie_pme_service_data *data = get_service_data(srv); struct pci_dev *port = srv->port; + bool wakeup; + if (device_may_wakeup(&port->dev)) { + wakeup = true; + } else { + down_read(&pci_bus_sem); + wakeup = pcie_pme_check_wakeup(port->subordinate); + up_read(&pci_bus_sem); + } spin_lock_irq(&data->lock); - pcie_pme_interrupt_enable(port, false); - pcie_clear_root_pme_status(port); - data->noirq = true; + if (wakeup) { + enable_irq_wake(srv->irq); + data->suspend_level = PME_SUSPEND_WAKEUP; + } else { + struct pci_dev *port = srv->port; + + pcie_pme_interrupt_enable(port, false); + pcie_clear_root_pme_status(port); + data->suspend_level = PME_SUSPEND_NOIRQ; + } spin_unlock_irq(&data->lock); synchronize_irq(srv->irq); @@ -394,12 +430,17 @@ static int pcie_pme_suspend(struct pcie_device *srv) static int pcie_pme_resume(struct pcie_device *srv) { struct pcie_pme_service_data *data = get_service_data(srv); - struct pci_dev *port = srv->port; spin_lock_irq(&data->lock); - data->noirq = false; - pcie_clear_root_pme_status(port); - pcie_pme_interrupt_enable(port, true); + if (data->suspend_level == PME_SUSPEND_NOIRQ) { + struct pci_dev *port = srv->port; + + pcie_clear_root_pme_status(port); + pcie_pme_interrupt_enable(port, true); + } else { + disable_irq_wake(srv->irq); + } + data->suspend_level = PME_SUSPEND_NONE; spin_unlock_irq(&data->lock); return 0; -- cgit v1.2.3