HID: Add input_register callback.

Add input_register callback which gets called after
hid_configure_usage is called for all the reports
and before the input device is registered. This allows
individual drivers to do extra work like input mapping just
before device registration.

Based on discussions with David Herrmann <dh.herrmann@googlemail.com>

Change-Id: Idab6fb4f7b1e5e569bd0410967288717e9d34c98
Signed-off-by: Jaikumar Ganesh <jaikumarg@android.com>

Changed to add return code to input_configured instead of
adding input_register

Signed-off-by: Arve Hjønnevåg <arve@android.com>

3 files changed, 18 insertions, 10 deletions

diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index 012880a2228c..90c718f6eded 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -1338,8 +1338,9 @@ int hidinput_connect(struct hid_device *hid, unsigned int force)
 				 * UGCI) cram a lot of unrelated inputs into the
 				 * same interface. */
 				hidinput->report = report;
-				if (drv->input_configured)
-					drv->input_configured(hid, hidinput);
+				if (drv->input_configured &&
+				    drv->input_configured(hid, hidinput))
+					goto out_cleanup;
 				if (input_register_device(hidinput->input))
 					goto out_cleanup;
 				hidinput = NULL;
@@ -1360,8 +1361,9 @@ int hidinput_connect(struct hid_device *hid, unsigned int force)
 	}
 
 	if (hidinput) {
-		if (drv->input_configured)
-			drv->input_configured(hid, hidinput);
+		if (drv->input_configured &&
+		    drv->input_configured(hid, hidinput))
+			goto out_cleanup;
 		if (input_register_device(hidinput->input))
 			goto out_cleanup;
 	}
diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index e45436b742d9..fb9ac1266719 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -782,12 +782,13 @@ static void mt_touch_report(struct hid_device *hid, struct hid_report *report)
 		mt_sync_frame(td, report->field[0]->hidinput->input);
 }
 
-static void mt_touch_input_configured(struct hid_device *hdev,
+static int mt_touch_input_configured(struct hid_device *hdev,
 					struct hid_input *hi)
 {
 	struct mt_device *td = hid_get_drvdata(hdev);
 	struct mt_class *cls = &td->mtclass;
 	struct input_dev *input = hi->input;
+	int ret;
 
 	if (!td->maxcontacts)
 		td->maxcontacts = MT_DEFAULT_MAXCONTACT;
@@ -802,9 +803,12 @@ static void mt_touch_input_configured(struct hid_device *hdev,
 	if (cls->quirks & MT_QUIRK_NOT_SEEN_MEANS_UP)
 		td->mt_flags |= INPUT_MT_DROP_UNUSED;
 
-	input_mt_init_slots(input, td->maxcontacts, td->mt_flags);
+	ret = input_mt_init_slots(input, td->maxcontacts, td->mt_flags);
+	if (ret)
+		return ret;
 
 	td->mt_flags = 0;
+	return 0;
 }
 
 static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi,
@@ -937,19 +941,21 @@ static void mt_post_parse(struct mt_device *td)
 		cls->quirks &= ~MT_QUIRK_CONTACT_CNT_ACCURATE;
 }
 
-static void mt_input_configured(struct hid_device *hdev, struct hid_input *hi)
+static int mt_input_configured(struct hid_device *hdev, struct hid_input *hi)
 {
 	struct mt_device *td = hid_get_drvdata(hdev);
 	char *name = kstrdup(hdev->name, GFP_KERNEL);
+	int ret = 0;
 
 	if (name)
 		hi->input->name = name;
 
 	if (hi->report->id == td->mt_report_id)
-		mt_touch_input_configured(hdev, hi);
+		ret = mt_touch_input_configured(hdev, hi);
 
 	if (hi->report->id == td->pen_report_id)
 		mt_pen_input_configured(hdev, hi);
+	return ret;
 }
 
 static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 4f8aa4733fb6..40e9c9d76d1e 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -649,8 +649,8 @@ 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);
-	void (*input_configured)(struct hid_device *hdev,
-				 struct hid_input *hidinput);
+	int (*input_configured)(struct hid_device *hdev,
+				struct hid_input *hidinput);
 	void (*feature_mapping)(struct hid_device *hdev,
 			struct hid_field *field,
 			struct hid_usage *usage);