[PATCH 1/2] hid: add suspend/resume hooks for hid drivers

["Bruno Prémont" <bonbons@linux-vserver.org>]

Add suspend/resume hooks for HID drivers so these can do some
additional state adjustment when device gets suspended/resumed.

v3:
  - Pass full message to hid driver's suspend hook
v2:
  - Adds auto_suspend parameter to suspend hook
  - Only calls HID driver's resume hooks when previous code
    did succeed

Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org>
---

Note, I've not added PM parts to bluetooth as I'm not sure how/where
to catch the PM events generated by bluetooth.
It looks like PM on bluetooth side does just some bluetooth housekeeping
and sends an event.
Marcel, do you have some pointers for wiring up these HID suspend hooks
in the bluetooth/hidp code?

 drivers/hid/usbhid/hid-core.c |   24 +++++++++++++++++++++++-
 include/linux/hid.h           |    8 ++++++++
 2 files changed, 31 insertions(+), 1 deletions(-)

diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index 3e7909b..17eb3ec 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -1291,6 +1291,11 @@ static int hid_suspend(struct usb_interface *intf, pm_message_t message)
 		{
 			set_bit(HID_REPORTED_IDLE, &usbhid->iofl);
 			spin_unlock_irq(&usbhid->lock);
+			if (hid->driver && hid->driver->suspend) {
+				status = hid->driver->suspend(hid, message);
+				if (status < 0)
+					return status;
+			}
 		} else {
 			usbhid_mark_busy(usbhid);
 			spin_unlock_irq(&usbhid->lock);
@@ -1298,6 +1303,11 @@ static int hid_suspend(struct usb_interface *intf, pm_message_t message)
 		}
 
 	} else {
+		if (hid->driver && hid->driver->suspend) {
+			status = hid->driver->suspend(hid, message);
+			if (status < 0)
+				return status;
+		}
 		spin_lock_irq(&usbhid->lock);
 		set_bit(HID_REPORTED_IDLE, &usbhid->iofl);
 		spin_unlock_irq(&usbhid->lock);
@@ -1352,6 +1362,11 @@ static int hid_resume(struct usb_interface *intf)
 		hid_io_error(hid);
 	usbhid_restart_queues(usbhid);
 
+	if (status >= 0 && hid->driver && hid->driver->resume) {
+		int ret = hid->driver->resume(hid);
+		if (ret < 0)
+			status = ret;
+	}
 	dev_dbg(&intf->dev, "resume status %d\n", status);
 	return 0;
 }
@@ -1360,9 +1375,16 @@ static int hid_reset_resume(struct usb_interface *intf)
 {
 	struct hid_device *hid = usb_get_intfdata(intf);
 	struct usbhid_device *usbhid = hid->driver_data;
+	int status;
 
 	clear_bit(HID_REPORTED_IDLE, &usbhid->iofl);
-	return hid_post_reset(intf);
+	status = hid_post_reset(intf);
+	if (status >= 0 && hid->driver && hid->driver->reset_resume) {
+		int ret = hid->driver->reset_resume(hid);
+		if (ret < 0)
+			status = ret;
+	}
+	return status;
 }
 
 #endif /* CONFIG_PM */
diff --git a/include/linux/hid.h b/include/linux/hid.h
index b1344ec..069e587 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -589,6 +589,9 @@ struct hid_usage_id {
  * @report_fixup: called before report descriptor parsing (NULL means nop)
  * @input_mapping: invoked on input registering before mapping an usage
  * @input_mapped: invoked on input registering after mapping an usage
+ * @suspend: invoked on suspend (NULL means nop)
+ * @resume: invoked on resume if device was not reset (NULL means nop)
+ * @reset_resume: invoked on resume if device was reset (NULL means nop)
  *
  * raw_event and event should return 0 on no action performed, 1 when no
  * further processing should be done and negative on error
@@ -629,6 +632,11 @@ struct hid_driver {
 	int (*input_mapped)(struct hid_device *hdev,
 			struct hid_input *hidinput, struct hid_field *field,
 			struct hid_usage *usage, unsigned long **bit, int *max);
+#ifdef CONFIG_PM
+	int (*suspend)(struct hid_device *hdev, pm_message_t message);
+	int (*resume)(struct hid_device *hdev);
+	int (*reset_resume)(struct hid_device *hdev);
+#endif
 /* private: */
 	struct device_driver driver;
 };
-- 
1.6.4.4