Revert "HID: Handle driver-specific device descriptor in core"

DO NOT INTEGRATE

Bug 1466757

This reverts commit 37ad3e3e97d734e74e071bf5e8796b22e16814e4.

Change-Id: I709cd76ccc70aee7d768ace2463b85049cc420f3
Signed-off-by: Kenneth Kwak <kkwak@nvidia.com>
Reviewed-on: http://git-master/r/428074
Reviewed-by: Peter Kim <pekim@nvidia.com>
Tested-by: Peter Kim <pekim@nvidia.com>

2 files changed, 32 insertions, 94 deletions

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 521df4d07491..ebb649103fcd 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -546,11 +546,12 @@ static void hid_free_report(struct hid_report *report)
 }
 
 /*
- * Close report. This function returns the device
- * state to the point prior to hid_open_report().
+ * Free a device structure, all reports, and all fields.
  */
-static void hid_close_report(struct hid_device *device)
+
+static void hid_device_release(struct device *dev)
 {
+	struct hid_device *device = container_of(dev, struct hid_device, dev);
 	unsigned i, j;
 
 	for (i = 0; i < HID_REPORT_TYPES; i++) {
@@ -561,34 +562,11 @@ static void hid_close_report(struct hid_device *device)
 			if (report)
 				hid_free_report(report);
 		}
-		memset(report_enum, 0, sizeof(*report_enum));
-		INIT_LIST_HEAD(&report_enum->report_list);
 	}
 
 	kfree(device->rdesc);
-	device->rdesc = NULL;
-	device->rsize = 0;
-
 	kfree(device->collection);
-	device->collection = NULL;
-	device->collection_size = 0;
-	device->maxcollection = 0;
-	device->maxapplication = 0;
-
-	device->status &= ~HID_STAT_PARSED;
-}
-
-/*
- * Free a device structure, all reports, and all fields.
- */
-
-static void hid_device_release(struct device *dev)
-{
-	struct hid_device *hid = container_of(dev, struct hid_device, dev);
-
-	hid_close_report(hid);
-	kfree(hid->dev_rdesc);
-	kfree(hid);
+	kfree(device);
 }
 
 /*
@@ -665,37 +643,15 @@ static u8 *fetch_item(__u8 *start, __u8 *end, struct hid_item *item)
  * @start: report start
  * @size: report size
  *
- * Allocate the device report as read by the bus driver. This function should
- * only be called from parse() in ll drivers.
- */
-int hid_parse_report(struct hid_device *hid, __u8 *start, unsigned size)
-{
-	hid->dev_rdesc = kmemdup(start, size, GFP_KERNEL);
-	if (!hid->dev_rdesc)
-		return -ENOMEM;
-	hid->dev_rsize = size;
-	return 0;
-}
-EXPORT_SYMBOL_GPL(hid_parse_report);
-
-/**
- * hid_open_report - open a driver-specific device report
- *
- * @device: hid device
- *
  * Parse a report description into a hid_device structure. Reports are
  * enumerated, fields are attached to these reports.
  * 0 returned on success, otherwise nonzero error value.
- *
- * This function (or the equivalent hid_parse() macro) should only be
- * called from probe() in drivers, before starting the device.
  */
-int hid_open_report(struct hid_device *device)
+int hid_parse_report(struct hid_device *device, __u8 *start,
+		unsigned size)
 {
 	struct hid_parser *parser;
 	struct hid_item item;
-	unsigned int size;
-	__u8 *start;
 	__u8 *end;
 	int ret;
 	static int (*dispatch_type[])(struct hid_parser *parser,
@@ -706,14 +662,6 @@ int hid_open_report(struct hid_device *device)
 		hid_parser_reserved
 	};
 
-	if (WARN_ON(device->status & HID_STAT_PARSED))
-		return -EBUSY;
-
-	start = device->dev_rdesc;
-	if (WARN_ON(!start))
-		return -ENODEV;
-	size = device->dev_rsize;
-
 	if (device->driver->report_fixup)
 		start = device->driver->report_fixup(device, start, &size);
 
@@ -731,15 +679,6 @@ int hid_open_report(struct hid_device *device)
 	parser->device = device;
 
 	end = start + size;
-
-	device->collection = kcalloc(HID_DEFAULT_NUM_COLLECTIONS,
-				     sizeof(struct hid_collection), GFP_KERNEL);
-	if (!device->collection) {
-		ret = -ENOMEM;
-		goto err;
-	}
-	device->collection_size = HID_DEFAULT_NUM_COLLECTIONS;
-
 	ret = -EINVAL;
 	while ((start = fetch_item(start, end, &item)) != NULL) {
 
@@ -765,7 +704,6 @@ int hid_open_report(struct hid_device *device)
 				goto err;
 			}
 			vfree(parser);
-			device->status |= HID_STAT_PARSED;
 			return 0;
 		}
 	}
@@ -773,10 +711,9 @@ int hid_open_report(struct hid_device *device)
 	hid_err(device, "item fetching failed at offset %d\n", (int)(end - start));
 err:
 	vfree(parser);
-	hid_close_report(device);
 	return ret;
 }
-EXPORT_SYMBOL_GPL(hid_open_report);
+EXPORT_SYMBOL_GPL(hid_parse_report);
 
 /*
  * Convert a signed n-bit integer to signed 32-bit integer. Common
@@ -1790,14 +1727,12 @@ static int hid_device_probe(struct device *dev)
 		if (hdrv->probe) {
 			ret = hdrv->probe(hdev, id);
 		} else { /* default probe */
-			ret = hid_open_report(hdev);
+			ret = hid_parse(hdev);
 			if (!ret)
 				ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
 		}
-		if (ret) {
-			hid_close_report(hdev);
+		if (ret)
 			hdev->driver = NULL;
-		}
 	}
 unlock:
 	up(&hdev->driver_lock);
@@ -1818,7 +1753,6 @@ static int hid_device_remove(struct device *dev)
 			hdrv->remove(hdev);
 		else /* default remove */
 			hid_hw_stop(hdev);
-		hid_close_report(hdev);
 		hdev->driver = NULL;
 	}
 
@@ -2155,16 +2089,6 @@ int hid_add_device(struct hid_device *hdev)
             && (hid_ignore(hdev) || (hdev->quirks & HID_QUIRK_IGNORE)))
 		return -ENODEV;
 
-	/*
-	 * Read the device report descriptor once and use as template
-	 * for the driver-specific modifications.
-	 */
-	ret = hdev->ll_driver->parse(hdev);
-	if (ret)
-		return ret;
-	if (!hdev->dev_rdesc)
-		return -ENODEV;
-
 	/* XXX hack, any other cleaner solution after the driver core
 	 * is converted to allow more than 20 bytes as the device name? */
 	dev_set_name(&hdev->dev, "%04X:%04X:%04X.%04X", hdev->bus,
@@ -2193,6 +2117,7 @@ EXPORT_SYMBOL_GPL(hid_add_device);
 struct hid_device *hid_allocate_device(void)
 {
 	struct hid_device *hdev;
+	unsigned int i;
 	int ret = -ENOMEM;
 
 	hdev = kzalloc(sizeof(*hdev), GFP_KERNEL);
@@ -2203,13 +2128,23 @@ struct hid_device *hid_allocate_device(void)
 	hdev->dev.release = hid_device_release;
 	hdev->dev.bus = &hid_bus_type;
 
-	hid_close_report(hdev);
+	hdev->collection = kcalloc(HID_DEFAULT_NUM_COLLECTIONS,
+			sizeof(struct hid_collection), GFP_KERNEL);
+	if (hdev->collection == NULL)
+		goto err;
+	hdev->collection_size = HID_DEFAULT_NUM_COLLECTIONS;
+
+	for (i = 0; i < HID_REPORT_TYPES; i++)
+		INIT_LIST_HEAD(&hdev->report_enum[i].report_list);
 
 	init_waitqueue_head(&hdev->debug_wait);
 	INIT_LIST_HEAD(&hdev->debug_list);
 	sema_init(&hdev->driver_lock, 1);
 
 	return hdev;
+err:
+	put_device(&hdev->dev);
+	return ERR_PTR(ret);
 }
 EXPORT_SYMBOL_GPL(hid_allocate_device);
 
@@ -2220,9 +2155,6 @@ static void hid_remove_device(struct hid_device *hdev)
 		hid_debug_unregister(hdev);
 		hdev->status &= ~HID_STAT_ADDED;
 	}
-	kfree(hdev->dev_rdesc);
-	hdev->dev_rdesc = NULL;
-	hdev->dev_rsize = 0;
 }
 
 /**
diff --git a/include/linux/hid.h b/include/linux/hid.h
index f1d71d5ce106..944e21cfc4d6 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -467,8 +467,6 @@ struct hid_driver;
 struct hid_ll_driver;
 
 struct hid_device {							/* device report descriptor */
-	__u8 *dev_rdesc;
-	unsigned dev_rsize;
 	__u8 *rdesc;
 	unsigned rsize;
 	struct hid_collection *collection;				/* List of HID collections */
@@ -747,7 +745,6 @@ void hid_output_report(struct hid_report *report, __u8 *data);
 struct hid_device *hid_allocate_device(void);
 struct hid_report *hid_register_report(struct hid_device *device, unsigned type, unsigned id);
 int hid_parse_report(struct hid_device *hid, __u8 *start, unsigned size);
-int hid_open_report(struct hid_device *device);
 int hid_check_keys_pressed(struct hid_device *hid);
 int hid_connect(struct hid_device *hid, unsigned int connect_mask);
 void hid_disconnect(struct hid_device *hid);
@@ -818,7 +815,16 @@ static inline void hid_map_usage_clear(struct hid_input *hidinput,
  */
 static inline int __must_check hid_parse(struct hid_device *hdev)
 {
-	return hid_open_report(hdev);
+	int ret;
+
+	if (hdev->status & HID_STAT_PARSED)
+		return 0;
+
+	ret = hdev->ll_driver->parse(hdev);
+	if (!ret)
+		hdev->status |= HID_STAT_PARSED;
+
+	return ret;
 }
 
 /**