HID: make debugging output runtime-configurable

There have been many reports recently about broken HID devices, the
diagnosis of which required users to recompile their kernels in order
to be able to provide debugging output needed for coding a quirk for
a particular device.

This patch makes CONFIG_HID_DEBUG default y if !EMBEDDED and makes it
possible to control debugging output produced by HID code by supplying
'debug=1' module parameter.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 47 insertions, 46 deletions

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 6ec04e79f685..317cf8a7b63c 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -40,6 +40,13 @@
 #define DRIVER_DESC "HID core driver"
 #define DRIVER_LICENSE "GPL"
 
+#ifdef CONFIG_HID_DEBUG
+int hid_debug = 0;
+module_param_named(debug, hid_debug, bool, 0600);
+MODULE_PARM_DESC(debug, "Turn HID debugging mode on and off");
+EXPORT_SYMBOL_GPL(hid_debug);
+#endif
+
 /*
  * Register a new report for a device.
  */
@@ -78,7 +85,7 @@ static struct hid_field *hid_register_field(struct hid_report *report, unsigned
 	struct hid_field *field;
 
 	if (report->maxfield == HID_MAX_FIELDS) {
-		dbg("too many fields in report");
+		dbg_hid("too many fields in report\n");
 		return NULL;
 	}
 
@@ -106,7 +113,7 @@ static int open_collection(struct hid_parser *parser, unsigned type)
 	usage = parser->local.usage[0];
 
 	if (parser->collection_stack_ptr == HID_COLLECTION_STACK_SIZE) {
-		dbg("collection stack overflow");
+		dbg_hid("collection stack overflow\n");
 		return -1;
 	}
 
@@ -114,7 +121,7 @@ static int open_collection(struct hid_parser *parser, unsigned type)
 		collection = kmalloc(sizeof(struct hid_collection) *
 				parser->device->collection_size * 2, GFP_KERNEL);
 		if (collection == NULL) {
-			dbg("failed to reallocate collection array");
+			dbg_hid("failed to reallocate collection array\n");
 			return -1;
 		}
 		memcpy(collection, parser->device->collection,
@@ -150,7 +157,7 @@ static int open_collection(struct hid_parser *parser, unsigned type)
 static int close_collection(struct hid_parser *parser)
 {
 	if (!parser->collection_stack_ptr) {
-		dbg("collection stack underflow");
+		dbg_hid("collection stack underflow\n");
 		return -1;
 	}
 	parser->collection_stack_ptr--;
@@ -178,7 +185,7 @@ static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type)
 static int hid_add_usage(struct hid_parser *parser, unsigned usage)
 {
 	if (parser->local.usage_index >= HID_MAX_USAGES) {
-		dbg("usage index exceeded");
+		dbg_hid("usage index exceeded\n");
 		return -1;
 	}
 	parser->local.usage[parser->local.usage_index] = usage;
@@ -202,12 +209,12 @@ static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsign
 	int i;
 
 	if (!(report = hid_register_report(parser->device, report_type, parser->global.report_id))) {
-		dbg("hid_register_report failed");
+		dbg_hid("hid_register_report failed\n");
 		return -1;
 	}
 
 	if (parser->global.logical_maximum < parser->global.logical_minimum) {
-		dbg("logical range invalid %d %d", parser->global.logical_minimum, parser->global.logical_maximum);
+		dbg_hid("logical range invalid %d %d\n", parser->global.logical_minimum, parser->global.logical_maximum);
 		return -1;
 	}
 
@@ -287,7 +294,7 @@ static int hid_parser_global(struct hid_parser *parser, struct hid_item *item)
 		case HID_GLOBAL_ITEM_TAG_PUSH:
 
 			if (parser->global_stack_ptr == HID_GLOBAL_STACK_SIZE) {
-				dbg("global enviroment stack overflow");
+				dbg_hid("global enviroment stack overflow\n");
 				return -1;
 			}
 
@@ -298,7 +305,7 @@ static int hid_parser_global(struct hid_parser *parser, struct hid_item *item)
 		case HID_GLOBAL_ITEM_TAG_POP:
 
 			if (!parser->global_stack_ptr) {
-				dbg("global enviroment stack underflow");
+				dbg_hid("global enviroment stack underflow\n");
 				return -1;
 			}
 
@@ -342,27 +349,27 @@ static int hid_parser_global(struct hid_parser *parser, struct hid_item *item)
 
 		case HID_GLOBAL_ITEM_TAG_REPORT_SIZE:
 			if ((parser->global.report_size = item_udata(item)) > 32) {
-				dbg("invalid report_size %d", parser->global.report_size);
+				dbg_hid("invalid report_size %d\n", parser->global.report_size);
 				return -1;
 			}
 			return 0;
 
 		case HID_GLOBAL_ITEM_TAG_REPORT_COUNT:
 			if ((parser->global.report_count = item_udata(item)) > HID_MAX_USAGES) {
-				dbg("invalid report_count %d", parser->global.report_count);
+				dbg_hid("invalid report_count %d\n", parser->global.report_count);
 				return -1;
 			}
 			return 0;
 
 		case HID_GLOBAL_ITEM_TAG_REPORT_ID:
 			if ((parser->global.report_id = item_udata(item)) == 0) {
-				dbg("report_id 0 is invalid");
+				dbg_hid("report_id 0 is invalid\n");
 				return -1;
 			}
 			return 0;
 
 		default:
-			dbg("unknown global tag 0x%x", item->tag);
+			dbg_hid("unknown global tag 0x%x\n", item->tag);
 			return -1;
 	}
 }
@@ -377,7 +384,7 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
 	unsigned n;
 
 	if (item->size == 0) {
-		dbg("item data expected for local item");
+		dbg_hid("item data expected for local item\n");
 		return -1;
 	}
 
@@ -395,14 +402,14 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
 				 * items and the first delimiter set.
 				 */
 				if (parser->local.delimiter_depth != 0) {
-					dbg("nested delimiters");
+					dbg_hid("nested delimiters\n");
 					return -1;
 				}
 				parser->local.delimiter_depth++;
 				parser->local.delimiter_branch++;
 			} else {
 				if (parser->local.delimiter_depth < 1) {
-					dbg("bogus close delimiter");
+					dbg_hid("bogus close delimiter\n");
 					return -1;
 				}
 				parser->local.delimiter_depth--;
@@ -412,7 +419,7 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
 		case HID_LOCAL_ITEM_TAG_USAGE:
 
 			if (parser->local.delimiter_branch > 1) {
-				dbg("alternative usage ignored");
+				dbg_hid("alternative usage ignored\n");
 				return 0;
 			}
 
@@ -424,7 +431,7 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
 		case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM:
 
 			if (parser->local.delimiter_branch > 1) {
-				dbg("alternative usage ignored");
+				dbg_hid("alternative usage ignored\n");
 				return 0;
 			}
 
@@ -437,7 +444,7 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
 		case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM:
 
 			if (parser->local.delimiter_branch > 1) {
-				dbg("alternative usage ignored");
+				dbg_hid("alternative usage ignored\n");
 				return 0;
 			}
 
@@ -446,14 +453,14 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
 
 			for (n = parser->local.usage_minimum; n <= data; n++)
 				if (hid_add_usage(parser, n)) {
-					dbg("hid_add_usage failed\n");
+					dbg_hid("hid_add_usage failed\n");
 					return -1;
 				}
 			return 0;
 
 		default:
 
-			dbg("unknown local item tag 0x%x", item->tag);
+			dbg_hid("unknown local item tag 0x%x\n", item->tag);
 			return 0;
 	}
 	return 0;
@@ -487,7 +494,7 @@ static int hid_parser_main(struct hid_parser *parser, struct hid_item *item)
 			ret = hid_add_field(parser, HID_FEATURE_REPORT, data);
 			break;
 		default:
-			dbg("unknown main item tag 0x%x", item->tag);
+			dbg_hid("unknown main item tag 0x%x\n", item->tag);
 			ret = 0;
 	}
 
@@ -502,7 +509,7 @@ static int hid_parser_main(struct hid_parser *parser, struct hid_item *item)
 
 static int hid_parser_reserved(struct hid_parser *parser, struct hid_item *item)
 {
-	dbg("reserved item type, tag 0x%x", item->tag);
+	dbg_hid("reserved item type, tag 0x%x\n", item->tag);
 	return 0;
 }
 
@@ -667,14 +674,14 @@ struct hid_device *hid_parse_report(__u8 *start, unsigned size)
 	while ((start = fetch_item(start, end, &item)) != NULL) {
 
 		if (item.format != HID_ITEM_FORMAT_SHORT) {
-			dbg("unexpected long global item");
+			dbg_hid("unexpected long global item\n");
 			hid_free_device(device);
 			vfree(parser);
 			return NULL;
 		}
 
 		if (dispatch_type[item.type](parser, &item)) {
-			dbg("item %u %u %u %u parsing failed\n",
+			dbg_hid("item %u %u %u %u parsing failed\n",
 				item.format, (unsigned)item.size, (unsigned)item.type, (unsigned)item.tag);
 			hid_free_device(device);
 			vfree(parser);
@@ -683,13 +690,13 @@ struct hid_device *hid_parse_report(__u8 *start, unsigned size)
 
 		if (start == end) {
 			if (parser->collection_stack_ptr) {
-				dbg("unbalanced collection at end of report description");
+				dbg_hid("unbalanced collection at end of report description\n");
 				hid_free_device(device);
 				vfree(parser);
 				return NULL;
 			}
 			if (parser->local.delimiter_depth) {
-				dbg("unbalanced delimiter at end of report description");
+				dbg_hid("unbalanced delimiter at end of report description\n");
 				hid_free_device(device);
 				vfree(parser);
 				return NULL;
@@ -699,7 +706,7 @@ struct hid_device *hid_parse_report(__u8 *start, unsigned size)
 		}
 	}
 
-	dbg("item fetching failed at offset %d\n", (int)(end - start));
+	dbg_hid("item fetching failed at offset %d\n", (int)(end - start));
 	hid_free_device(device);
 	vfree(parser);
 	return NULL;
@@ -915,13 +922,13 @@ int hid_set_field(struct hid_field *field, unsigned offset, __s32 value)
 	hid_dump_input(field->usage + offset, value);
 
 	if (offset >= field->report_count) {
-		dbg("offset (%d) exceeds report_count (%d)", offset, field->report_count);
+		dbg_hid("offset (%d) exceeds report_count (%d)\n", offset, field->report_count);
 		hid_dump_field(field, 8);
 		return -1;
 	}
 	if (field->logical_minimum < 0) {
 		if (value != snto32(s32ton(value, size), size)) {
-			dbg("value %d is out of range", value);
+			dbg_hid("value %d is out of range\n", value);
 			return -1;
 		}
 	}
@@ -934,19 +941,17 @@ int hid_input_report(struct hid_device *hid, int type, u8 *data, int size, int i
 {
 	struct hid_report_enum *report_enum = hid->report_enum + type;
 	struct hid_report *report;
-	int n, rsize;
+	int n, rsize, i;
 
 	if (!hid)
 		return -ENODEV;
 
 	if (!size) {
-		dbg("empty report");
+		dbg_hid("empty report\n");
 		return -1;
 	}
 
-#ifdef CONFIG_HID_DEBUG
-	printk(KERN_DEBUG __FILE__ ": report (size %u) (%snumbered)\n", size, report_enum->numbered ? "" : "un");
-#endif
+	dbg_hid("report (size %u) (%snumbered)\n", size, report_enum->numbered ? "" : "un");
 
 	n = 0;                          /* Normally report number is 0 */
 	if (report_enum->numbered) {    /* Device uses numbered reports, data[0] is report number */
@@ -954,25 +959,21 @@ int hid_input_report(struct hid_device *hid, int type, u8 *data, int size, int i
 		size--;
 	}
 
-#ifdef CONFIG_HID_DEBUG
-	{
-		int i;
-		printk(KERN_DEBUG __FILE__ ": report %d (size %u) = ", n, size);
-		for (i = 0; i < size; i++)
-			printk(" %02x", data[i]);
-		printk("\n");
-	}
-#endif
+	/* dump the report descriptor */
+	dbg_hid("report %d (size %u) = ", n, size);
+	for (i = 0; i < size; i++)
+		dbg_hid_line(" %02x", data[i]);
+	dbg_hid_line("\n");
 
 	if (!(report = report_enum->report_id_hash[n])) {
-		dbg("undefined report_id %d received", n);
+		dbg_hid("undefined report_id %d received\n", n);
 		return -1;
 	}
 
 	rsize = ((report->size - 1) >> 3) + 1;
 
 	if (size < rsize) {
-		dbg("report %d is too short, (%d < %d)", report->id, size, rsize);
+		dbg_hid("report %d is too short, (%d < %d)\n", report->id, size, rsize);
 		memset(data + size, 0, rsize - size);
 	}