libata-acpi: add ata port runtime D3Cold support

ATA port may support runtime D3Cold state, for example, Zero-power ODD case.
This patch adds wakeup notifier and enable/disable run_wake during
supend/resume.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 74 insertions, 4 deletions

diff --git a/drivers/ata/libata-acpi.c b/drivers/ata/libata-acpi.c
index bb20fd597eb1..e01807a1ef31 100644
--- a/drivers/ata/libata-acpi.c
+++ b/drivers/ata/libata-acpi.c
@@ -16,6 +16,7 @@
 #include <linux/libata.h>
 #include <linux/pci.h>
 #include <linux/slab.h>
+#include <linux/pm_runtime.h>
 #include <scsi/scsi_device.h>
 #include "libata.h"
 
@@ -853,6 +854,7 @@ void ata_acpi_set_state(struct ata_port *ap, pm_message_t state)
 {
         struct ata_device *dev;
         acpi_handle handle;
+        int acpi_state;
 
         /* channel first and then drives for power on and vica versa
            for power off */
@@ -862,10 +864,23 @@ void ata_acpi_set_state(struct ata_port *ap, pm_message_t state)
 
         ata_for_each_dev(dev, &ap->link, ENABLED) {
                 handle = ata_dev_acpi_handle(dev);
-                if (handle)
-                        acpi_bus_set_power(handle,
-                                state.event == PM_EVENT_ON ?
-                                        ACPI_STATE_D0 : ACPI_STATE_D3);
+                if (!handle)
+                        continue;
+
+                if (state.event != PM_EVENT_ON) {
+                        acpi_state = acpi_pm_device_sleep_state(
+                                &dev->sdev->sdev_gendev, NULL);
+                        if (acpi_state > 0)
+                                acpi_bus_set_power(handle, acpi_state);
+                        /* TBD: need to check if it's runtime pm request */
+                        acpi_pm_device_run_wake(
+                                &dev->sdev->sdev_gendev, true);
+                } else {
+                        /* Ditto */
+                        acpi_pm_device_run_wake(
+                                &dev->sdev->sdev_gendev, false);
+                        acpi_bus_set_power(handle, ACPI_STATE_D0);
+                }
         }
 
         handle = ata_ap_acpi_handle(ap);
@@ -965,6 +980,61 @@ void ata_acpi_on_disable(struct ata_device *dev)
         ata_acpi_clear_gtf(dev);
 }
 
+static void ata_acpi_wake_dev(acpi_handle handle, u32 event, void *context)
+{
+        struct ata_device *ata_dev = context;
+
+        if (event == ACPI_NOTIFY_DEVICE_WAKE && ata_dev &&
+                        pm_runtime_suspended(&ata_dev->sdev->sdev_gendev))
+                scsi_autopm_get_device(ata_dev->sdev);
+}
+
+static void ata_acpi_add_pm_notifier(struct ata_device *dev)
+{
+        struct acpi_device *acpi_dev;
+        acpi_handle handle;
+        acpi_status status;
+
+        handle = ata_dev_acpi_handle(dev);
+        if (!handle)
+                return;
+
+        status = acpi_bus_get_device(handle, &acpi_dev);
+        if (ACPI_SUCCESS(status)) {
+                acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
+                        ata_acpi_wake_dev, dev);
+                device_set_run_wake(&dev->sdev->sdev_gendev, true);
+        }
+}
+
+static void ata_acpi_remove_pm_notifier(struct ata_device *dev)
+{
+        struct acpi_device *acpi_dev;
+        acpi_handle handle;
+        acpi_status status;
+
+        handle = ata_dev_acpi_handle(dev);
+        if (!handle)
+                return;
+
+        status = acpi_bus_get_device(handle, &acpi_dev);
+        if (ACPI_SUCCESS(status)) {
+                device_set_run_wake(&dev->sdev->sdev_gendev, false);
+                acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
+                        ata_acpi_wake_dev);
+        }
+}
+
+void ata_acpi_bind(struct ata_device *dev)
+{
+        ata_acpi_add_pm_notifier(dev);
+}
+
+void ata_acpi_unbind(struct ata_device *dev)
+{
+        ata_acpi_remove_pm_notifier(dev);
+}
+
 static int compat_pci_ata(struct ata_port *ap)
 {
         struct device *dev = ap->tdev.parent;