[PATCH v8 03/11] ata: zpodd: identify and init ZPODD devices

[Aaron Lu <aaron.lu@intel.com>]

If the ODD supports device attention and the platform can runtime
power off it through ACPI, it means this ODD together with this platform
is ZPODD capable. For this case, zpodd_init is called and a new
structure is allocated for the device to store ZPODD related stuffs.

And the zpodd_dev_enabled function is used to test if ZPODD is currently
enabled for this ODD.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
---
 drivers/ata/libata-acpi.c | 32 ++++++++++++++++++++++++++++++++
 drivers/ata/sata_zpodd.c  | 23 +++++++++++++++++++++++
 drivers/ata/sata_zpodd.h  | 24 ++++++++++++++++++++++++
 3 files changed, 79 insertions(+)

diff --git a/drivers/ata/libata-acpi.c b/drivers/ata/libata-acpi.c
index fd9ecf7..53b2f10 100644
--- a/drivers/ata/libata-acpi.c
+++ b/drivers/ata/libata-acpi.c
@@ -19,6 +19,7 @@
 #include <linux/pm_runtime.h>
 #include <scsi/scsi_device.h>
 #include "libata.h"
+#include "sata_zpodd.h"
 
 #include <acpi/acpi_bus.h>
 
@@ -1051,14 +1052,45 @@ static void ata_acpi_unregister_power_resource(struct ata_device *dev)
 	acpi_power_resource_unregister_device(device, handle);
 }
 
+static bool ata_acpi_device_poweroff(struct ata_device *ata_dev)
+{
+	acpi_handle handle;
+	acpi_status status;
+	struct acpi_device_power_state *states;
+	struct acpi_device *acpi_dev;
+
+	handle = DEVICE_ACPI_HANDLE(&ata_dev->sdev->sdev_gendev);
+	if (!handle)
+		return false;
+
+	status = acpi_bus_get_device(handle, &acpi_dev);
+	if (ACPI_FAILURE(status))
+		return false;
+
+	/*
+	 * If firmware has _PS3 or _PR3 for this device,
+	 * it means this device can be runtime powered off
+	 */
+	states = acpi_dev->power.states;
+	if (states[ACPI_STATE_D3_HOT].flags.valid ||
+	    states[ACPI_STATE_D3_COLD].flags.explicit_set)
+		return true;
+	else
+		return false;
+}
+
 void ata_acpi_bind(struct ata_device *dev)
 {
 	ata_acpi_add_pm_notifier(dev);
 	ata_acpi_register_power_resource(dev);
+	if (dev->flags & ATA_DFLAG_DA && ata_acpi_device_poweroff(dev))
+		zpodd_init(dev);
 }
 
 void ata_acpi_unbind(struct ata_device *dev)
 {
+	if (zpodd_dev_enabled(dev))
+		zpodd_deinit(dev);
 	ata_acpi_remove_pm_notifier(dev);
 	ata_acpi_unregister_power_resource(dev);
 }
diff --git a/drivers/ata/sata_zpodd.c b/drivers/ata/sata_zpodd.c
index e69de29..b37db2f 100644
--- a/drivers/ata/sata_zpodd.c
+++ b/drivers/ata/sata_zpodd.c
@@ -0,0 +1,23 @@
+#include <linux/libata.h>
+
+struct zpodd {
+	struct ata_device *dev;
+};
+
+
+void zpodd_init(struct ata_device *dev)
+{
+	struct zpodd *zpodd;
+	zpodd = kzalloc(sizeof(struct zpodd), GFP_KERNEL);
+	if (!zpodd)
+		return;
+
+	zpodd->dev = dev;
+	dev->private_data = zpodd;
+}
+
+void zpodd_deinit(struct ata_device *dev)
+{
+	kfree(dev->private_data);
+	dev->private_data = NULL;
+}
diff --git a/drivers/ata/sata_zpodd.h b/drivers/ata/sata_zpodd.h
index e69de29..e320c6f 100644
--- a/drivers/ata/sata_zpodd.h
+++ b/drivers/ata/sata_zpodd.h
@@ -0,0 +1,24 @@
+#ifndef __SATA_ZPODD_H__
+#define __SATA_ZPODD_H__
+
+#include <linux/libata.h>
+
+#ifdef CONFIG_SATA_ZPODD
+void zpodd_init(struct ata_device *);
+void zpodd_deinit(struct ata_device *);
+
+static bool zpodd_dev_enabled(struct ata_device *dev)
+{
+	if (dev->flags & ATA_DFLAG_DA && dev->private_data)
+		return true;
+	else
+		return false;
+}
+
+#else
+static inline void zpodd_init(struct ata_device *dev) {}
+static inline void zpodd_deinit(struct ata_device *dev) {}
+static inline bool zpodd_dev_enabled(struct ata_device *dev) { return false; }
+#endif
+
+#endif
-- 
1.7.12.4