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 <rafael.j.wysocki@intel.com>
This commit is contained in:
Rafael J. Wysocki 2014-09-01 13:49:16 +02:00
parent 5613570b13
commit 76cde7e495
1 changed files with 51 additions and 10 deletions

View File

@ -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;