PNPACPI: Add support for remote wakeup

This patch (as1354) adds remote-wakeup support to the pnpacpi driver.
The new can_wakeup method also allows other PNP protocol drivers
(pnpbios or iaspnp) to add wakeup support, but I don't know enough
about how they work to actually do it.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reviewed-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

2 files changed, 26 insertions, 0 deletions

diff --git a/drivers/pnp/core.c b/drivers/pnp/core.c
index 5dba90995d9e..88b3cde52596 100644
--- a/drivers/pnp/core.c
+++ b/drivers/pnp/core.c
@@ -164,6 +164,9 @@ int __pnp_add_device(struct pnp_dev *dev)
         list_add_tail(&dev->global_list, &pnp_global);
         list_add_tail(&dev->protocol_list, &dev->protocol->devices);
         spin_unlock(&pnp_lock);
+        if (dev->protocol->can_wakeup)
+                device_set_wakeup_capable(&dev->dev,
+                                dev->protocol->can_wakeup(dev));
         return device_register(&dev->dev);
 }
 
diff --git a/drivers/pnp/pnpacpi/core.c b/drivers/pnp/pnpacpi/core.c
index f7ff628b7d94..dc4e32e031e9 100644
--- a/drivers/pnp/pnpacpi/core.c
+++ b/drivers/pnp/pnpacpi/core.c
@@ -122,17 +122,37 @@ static int pnpacpi_disable_resources(struct pnp_dev *dev)
 }
 
 #ifdef CONFIG_ACPI_SLEEP
+static bool pnpacpi_can_wakeup(struct pnp_dev *dev)
+{
+        struct acpi_device *acpi_dev = dev->data;
+        acpi_handle handle = acpi_dev->handle;
+
+        return acpi_bus_can_wakeup(handle);
+}
+
 static int pnpacpi_suspend(struct pnp_dev *dev, pm_message_t state)
 {
         struct acpi_device *acpi_dev = dev->data;
         acpi_handle handle = acpi_dev->handle;
         int power_state;
 
+        if (device_can_wakeup(&dev->dev)) {
+                int rc = acpi_pm_device_sleep_wake(&dev->dev,
+                                device_may_wakeup(&dev->dev));
+
+                if (rc)
+                        return rc;
+        }
         power_state = acpi_pm_device_sleep_state(&dev->dev, NULL);
         if (power_state < 0)
                 power_state = (state.event == PM_EVENT_ON) ?
                                 ACPI_STATE_D0 : ACPI_STATE_D3;
 
+        /* acpi_bus_set_power() often fails (keyboard port can't be
+         * powered-down?), and in any case, our return value is ignored
+         * by pnp_bus_suspend().  Hence we don't revert the wakeup
+         * setting if the set_power fails.
+         */
         return acpi_bus_set_power(handle, power_state);
 }
 
@@ -141,6 +161,8 @@ static int pnpacpi_resume(struct pnp_dev *dev)
         struct acpi_device *acpi_dev = dev->data;
         acpi_handle handle = acpi_dev->handle;
 
+        if (device_may_wakeup(&dev->dev))
+                acpi_pm_device_sleep_wake(&dev->dev, false);
         return acpi_bus_set_power(handle, ACPI_STATE_D0);
 }
 #endif
@@ -151,6 +173,7 @@ struct pnp_protocol pnpacpi_protocol = {
         .set     = pnpacpi_set_resources,
         .disable = pnpacpi_disable_resources,
 #ifdef CONFIG_ACPI_SLEEP
+        .can_wakeup = pnpacpi_can_wakeup,
         .suspend = pnpacpi_suspend,
         .resume = pnpacpi_resume,
 #endif