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>
diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 8fbe9fd..5b004b2 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -24,6 +24,7 @@
 
 config HID_DEBUG
 	bool "HID debugging support"
+	default y if !EMBEDDED
 	depends on HID
 	---help---
 	This option lets the HID layer output diagnostics about its internal
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 6ec04e7..317cf8a 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 @@
 	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 @@
 	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 @@
 		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 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 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 @@
 	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 @@
 		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 @@
 		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 @@
 
 		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 @@
 	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 @@
 				 * 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 @@
 		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 @@
 		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 @@
 		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 @@
 
 			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 @@
 			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_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 @@
 	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 @@
 
 		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 @@
 		}
 	}
 
-	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 @@
 	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 @@
 {
 	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 @@
 		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);
 	}
 
diff --git a/drivers/hid/hid-debug.c b/drivers/hid/hid-debug.c
index 83c4126..a13757b 100644
--- a/drivers/hid/hid-debug.c
+++ b/drivers/hid/hid-debug.c
@@ -347,6 +347,9 @@
 void hid_resolv_usage(unsigned usage) {
 	const struct hid_usage_entry *p;
 
+	if (!hid_debug)
+		return;
+
 	resolv_usage_page(usage >> 16);
 	printk(".");
 	for (p = hid_usage_table; p->description; p++)
@@ -369,6 +372,9 @@
 void hid_dump_field(struct hid_field *field, int n) {
 	int j;
 
+	if (!hid_debug)
+		return;
+
 	if (field->physical) {
 		tab(n);
 		printk("Physical(");
@@ -466,6 +472,9 @@
 	unsigned i,k;
 	static char *table[] = {"INPUT", "OUTPUT", "FEATURE"};
 
+	if (!hid_debug)
+		return;
+
 	for (i = 0; i < HID_REPORT_TYPES; i++) {
 		report_enum = device->report_enum + i;
 		list = report_enum->report_list.next;
@@ -489,6 +498,9 @@
 EXPORT_SYMBOL_GPL(hid_dump_device);
 
 void hid_dump_input(struct hid_usage *usage, __s32 value) {
+	if (!hid_debug)
+		return;
+
 	printk("hid-debug: input ");
 	hid_resolv_usage(usage->hid);
 	printk(" = %d\n", value);
@@ -758,6 +770,9 @@
 
 void hid_resolv_event(__u8 type, __u16 code) {
 
+	if (!hid_debug)
+		return;
+
 	printk("%s.%s", events[type] ? events[type] : "?",
 		names[type] ? (names[type][code] ? names[type][code] : "?") : "?");
 }
diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index 7f81789..38595d3 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -308,9 +308,7 @@
 		
 		clear_bit(old_keycode, dev->keybit);
 		set_bit(usage->code, dev->keybit);
-#ifdef CONFIG_HID_DEBUG
-		printk (KERN_DEBUG "Assigned keycode %d to HID usage code %x\n", keycode, scancode);
-#endif
+		dbg_hid(KERN_DEBUG "Assigned keycode %d to HID usage code %x\n", keycode, scancode);
 		/* Set the keybit for the old keycode if the old keycode is used
 		 * by another key */
 		if (hidinput_find_key (hid, 0, old_keycode))
@@ -333,11 +331,9 @@
 
 	field->hidinput = hidinput;
 
-#ifdef CONFIG_HID_DEBUG
-	printk(KERN_DEBUG "Mapping: ");
+	dbg_hid("Mapping: ");
 	hid_resolv_usage(usage->hid);
-	printk(" ---> ");
-#endif
+	dbg_hid_line(" ---> ");
 
 	if (field->flags & HID_MAIN_ITEM_CONSTANT)
 		goto ignore;
@@ -819,15 +815,13 @@
 	}
 
 	hid_resolv_event(usage->type, usage->code);
-#ifdef CONFIG_HID_DEBUG
-	printk("\n");
-#endif
+
+	dbg_hid_line("\n");
+
 	return;
 
 ignore:
-#ifdef CONFIG_HID_DEBUG
-	printk("IGNORED\n");
-#endif
+	dbg_hid_line("IGNORED\n");
 	return;
 }
 
@@ -896,12 +890,12 @@
 	}
 
 	if (usage->hid == (HID_UP_PID | 0x83UL)) { /* Simultaneous Effects Max */
-		dbg("Maximum Effects - %d",value);
+		dbg_hid("Maximum Effects - %d\n",value);
 		return;
 	}
 
 	if (usage->hid == (HID_UP_PID | 0x7fUL)) {
-		dbg("PID Pool Report\n");
+		dbg_hid("PID Pool Report\n");
 		return;
 	}
 
@@ -994,7 +988,7 @@
 				if (!hidinput || !input_dev) {
 					kfree(hidinput);
 					input_free_device(input_dev);
-					err("Out of memory during hid input probe");
+					err_hid("Out of memory during hid input probe");
 					return -1;
 				}
 
diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index d91b9da..1eb2c64 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -127,7 +127,7 @@
 			hid_io_error(hid);
 		break;
 	default:
-		err("can't reset device, %s-%s/input%d, status %d",
+		err_hid("can't reset device, %s-%s/input%d, status %d",
 				hid_to_usb_dev(hid)->bus->bus_name,
 				hid_to_usb_dev(hid)->devpath,
 				usbhid->ifnum, rc);
@@ -220,7 +220,7 @@
 	if (status) {
 		clear_bit(HID_IN_RUNNING, &usbhid->iofl);
 		if (status != -EPERM) {
-			err("can't resubmit intr, %s-%s/input%d, status %d",
+			err_hid("can't resubmit intr, %s-%s/input%d, status %d",
 					hid_to_usb_dev(hid)->bus->bus_name,
 					hid_to_usb_dev(hid)->devpath,
 					usbhid->ifnum, status);
@@ -240,10 +240,10 @@
 	usbhid->urbout->transfer_buffer_length = ((report->size - 1) >> 3) + 1 + (report->id > 0);
 	usbhid->urbout->dev = hid_to_usb_dev(hid);
 
-	dbg("submitting out urb");
+	dbg_hid("submitting out urb\n");
 
 	if (usb_submit_urb(usbhid->urbout, GFP_ATOMIC)) {
-		err("usb_submit_urb(out) failed");
+		err_hid("usb_submit_urb(out) failed");
 		return -1;
 	}
 
@@ -287,12 +287,12 @@
 	usbhid->cr->wIndex = cpu_to_le16(usbhid->ifnum);
 	usbhid->cr->wLength = cpu_to_le16(len);
 
-	dbg("submitting ctrl urb: %s wValue=0x%04x wIndex=0x%04x wLength=%u",
+	dbg_hid("submitting ctrl urb: %s wValue=0x%04x wIndex=0x%04x wLength=%u\n",
 		usbhid->cr->bRequest == HID_REQ_SET_REPORT ? "Set_Report" : "Get_Report",
 		usbhid->cr->wValue, usbhid->cr->wIndex, usbhid->cr->wLength);
 
 	if (usb_submit_urb(usbhid->urbctrl, GFP_ATOMIC)) {
-		err("usb_submit_urb(ctrl) failed");
+		err_hid("usb_submit_urb(ctrl) failed");
 		return -1;
 	}
 
@@ -474,7 +474,7 @@
 	if (!wait_event_timeout(hid->wait, (!test_bit(HID_CTRL_RUNNING, &usbhid->iofl) &&
 					!test_bit(HID_OUT_RUNNING, &usbhid->iofl)),
 					10*HZ)) {
-		dbg("timeout waiting for ctrl or out queue to clear");
+		dbg_hid("timeout waiting for ctrl or out queue to clear\n");
 		return -1;
 	}
 
@@ -667,7 +667,7 @@
 				 USB_CTRL_GET_TIMEOUT);
 
 	if (result < 0)
-		err("%s failed: %d\n", __func__, result);
+		err_hid("%s failed: %d\n", __func__, result);
 
 	kfree(buf);
 }
@@ -746,7 +746,7 @@
 	if (usb_get_extra_descriptor(interface, HID_DT_HID, &hdesc) &&
 	    (!interface->desc.bNumEndpoints ||
 	     usb_get_extra_descriptor(&interface->endpoint[0], HID_DT_HID, &hdesc))) {
-		dbg("class descriptor not present\n");
+		dbg_hid("class descriptor not present\n");
 		return NULL;
 	}
 
@@ -755,19 +755,19 @@
 			rsize = le16_to_cpu(hdesc->desc[n].wDescriptorLength);
 
 	if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
-		dbg("weird size of report descriptor (%u)", rsize);
+		dbg_hid("weird size of report descriptor (%u)\n", rsize);
 		return NULL;
 	}
 
 	if (!(rdesc = kmalloc(rsize, GFP_KERNEL))) {
-		dbg("couldn't allocate rdesc memory");
+		dbg_hid("couldn't allocate rdesc memory\n");
 		return NULL;
 	}
 
 	hid_set_idle(dev, interface->desc.bInterfaceNumber, 0, 0);
 
 	if ((n = hid_get_class_descriptor(dev, interface->desc.bInterfaceNumber, HID_DT_REPORT, rdesc, rsize)) < 0) {
-		dbg("reading report descriptor failed");
+		dbg_hid("reading report descriptor failed\n");
 		kfree(rdesc);
 		return NULL;
 	}
@@ -781,15 +781,13 @@
 	if (quirks & HID_QUIRK_SWAPPED_MIN_MAX)
 		hid_fixup_cypress_descriptor(rdesc, rsize);
 
-#ifdef CONFIG_HID_DEBUG
-	printk(KERN_DEBUG __FILE__ ": report descriptor (size %u, read %d) = ", rsize, n);
+	dbg_hid("report descriptor (size %u, read %d) = ", rsize, n);
 	for (n = 0; n < rsize; n++)
-		printk(" %02x", (unsigned char) rdesc[n]);
-	printk("\n");
-#endif
+		dbg_hid_line(" %02x", (unsigned char) rdesc[n]);
+	dbg_hid_line("\n");
 
 	if (!(hid = hid_parse_report(rdesc, n))) {
-		dbg("parsing report descriptor failed");
+		dbg_hid("parsing report descriptor failed\n");
 		kfree(rdesc);
 		return NULL;
 	}
@@ -861,7 +859,7 @@
 	}
 
 	if (!usbhid->urbin) {
-		err("couldn't find an input interrupt endpoint");
+		err_hid("couldn't find an input interrupt endpoint");
 		goto fail;
 	}
 
@@ -978,7 +976,7 @@
 	int i;
 	char *c;
 
-	dbg("HID probe called for ifnum %d",
+	dbg_hid("HID probe called for ifnum %d\n",
 			intf->altsetting->desc.bInterfaceNumber);
 
 	if (!(hid = usb_hid_configure(intf)))
diff --git a/drivers/hid/usbhid/hid-lgff.c b/drivers/hid/usbhid/hid-lgff.c
index c5cd410..4b7ab6a 100644
--- a/drivers/hid/usbhid/hid-lgff.c
+++ b/drivers/hid/usbhid/hid-lgff.c
@@ -78,7 +78,7 @@
 		report->field[0]->value[1] = 0x08;
 		report->field[0]->value[2] = x;
 		report->field[0]->value[3] = y;
-		dbg("(x, y)=(%04x, %04x)", x, y);
+		dbg_hid("(x, y)=(%04x, %04x)\n", x, y);
 		usbhid_submit_report(hid, report, USB_DIR_OUT);
 		break;
 
@@ -93,7 +93,7 @@
 		report->field[0]->value[1] = 0x00;
 		report->field[0]->value[2] = left;
 		report->field[0]->value[3] = right;
-		dbg("(left, right)=(%04x, %04x)", left, right);
+		dbg_hid("(left, right)=(%04x, %04x)\n", left, right);
 		usbhid_submit_report(hid, report, USB_DIR_OUT);
 		break;
 	}
@@ -113,20 +113,20 @@
 
 	/* Find the report to use */
 	if (list_empty(report_list)) {
-		err("No output report found");
+		err_hid("No output report found");
 		return -1;
 	}
 
 	/* Check that the report looks ok */
 	report = list_entry(report_list->next, struct hid_report, list);
 	if (!report) {
-		err("NULL output report");
+		err_hid("NULL output report");
 		return -1;
 	}
 
 	field = report->field[0];
 	if (!field) {
-		err("NULL field");
+		err_hid("NULL field");
 		return -1;
 	}
 
diff --git a/drivers/hid/usbhid/hid-quirks.c b/drivers/hid/usbhid/hid-quirks.c
index f6c4145..a418ebfe 100644
--- a/drivers/hid/usbhid/hid-quirks.c
+++ b/drivers/hid/usbhid/hid-quirks.c
@@ -493,7 +493,7 @@
 	}
 
 	if (bl_entry != NULL)
-		dbg("Found dynamic quirk 0x%x for USB HID vendor 0x%hx prod 0x%hx\n",
+		dbg_hid("Found dynamic quirk 0x%x for USB HID vendor 0x%hx prod 0x%hx\n",
 				bl_entry->quirks, bl_entry->idVendor,
 				bl_entry->idProduct);
 
@@ -521,13 +521,13 @@
 	int list_edited = 0;
 
 	if (!idVendor) {
-		dbg("Cannot add a quirk with idVendor = 0");
+		dbg_hid("Cannot add a quirk with idVendor = 0\n");
 		return -EINVAL;
 	}
 
 	q_new = kmalloc(sizeof(struct quirks_list_struct), GFP_KERNEL);
 	if (!q_new) {
-		dbg("Could not allocate quirks_list_struct");
+		dbg_hid("Could not allocate quirks_list_struct\n");
 		return -ENOMEM;
 	}
 
@@ -643,7 +643,7 @@
 			bl_entry = &hid_blacklist[n];
 
 	if (bl_entry != NULL)
-		dbg("Found squirk 0x%x for USB HID vendor 0x%hx prod 0x%hx\n",
+		dbg_hid("Found squirk 0x%x for USB HID vendor 0x%hx prod 0x%hx\n",
 				bl_entry->quirks, bl_entry->idVendor, 
 				bl_entry->idProduct);
 	return bl_entry;
diff --git a/drivers/hid/usbhid/hid-tmff.c b/drivers/hid/usbhid/hid-tmff.c
index ab5ba6e..555bb48 100644
--- a/drivers/hid/usbhid/hid-tmff.c
+++ b/drivers/hid/usbhid/hid-tmff.c
@@ -70,7 +70,7 @@
 
 	tmff->rumble->value[0] = left;
 	tmff->rumble->value[1] = right;
-	dbg("(left,right)=(%08x, %08x)", left, right);
+	dbg_hid("(left,right)=(%08x, %08x)\n", left, right);
 	usbhid_submit_report(hid, tmff->report, USB_DIR_OUT);
 
 	return 0;
diff --git a/drivers/hid/usbhid/hid-zpff.c b/drivers/hid/usbhid/hid-zpff.c
index a7fbffc..5a68827 100644
--- a/drivers/hid/usbhid/hid-zpff.c
+++ b/drivers/hid/usbhid/hid-zpff.c
@@ -21,10 +21,6 @@
  */
 
 
-/* #define DEBUG */
-
-#define debug(format, arg...) pr_debug("hid-zpff: " format "\n" , ## arg)
-
 #include <linux/input.h>
 #include <linux/usb.h>
 #include <linux/hid.h>
@@ -49,14 +45,14 @@
 
 	left = effect->u.rumble.strong_magnitude;
 	right = effect->u.rumble.weak_magnitude;
-	debug("called with 0x%04x 0x%04x", left, right);
+	dbg_hid("called with 0x%04x 0x%04x\n", left, right);
 
 	left = left * 0x7f / 0xffff;
 	right = right * 0x7f / 0xffff;
 
 	zpff->report->field[2]->value[0] = left;
 	zpff->report->field[3]->value[0] = right;
-	debug("running with 0x%02x 0x%02x", left, right);
+	dbg_hid("running with 0x%02x 0x%02x\n", left, right);
 	usbhid_submit_report(hid, zpff->report, USB_DIR_OUT);
 
 	return 0;
diff --git a/drivers/hid/usbhid/hiddev.c b/drivers/hid/usbhid/hiddev.c
index 488d61b..e793127 100644
--- a/drivers/hid/usbhid/hiddev.c
+++ b/drivers/hid/usbhid/hiddev.c
@@ -779,7 +779,7 @@
 
 	retval = usb_register_dev(usbhid->intf, &hiddev_class);
 	if (retval) {
-		err("Not able to get a minor for this device.");
+		err_hid("Not able to get a minor for this device.");
 		kfree(hiddev);
 		return -1;
 	}
diff --git a/drivers/hid/usbhid/usbkbd.c b/drivers/hid/usbhid/usbkbd.c
index 1309787..b76b02f 100644
--- a/drivers/hid/usbhid/usbkbd.c
+++ b/drivers/hid/usbhid/usbkbd.c
@@ -125,7 +125,7 @@
 resubmit:
 	i = usb_submit_urb (urb, GFP_ATOMIC);
 	if (i)
-		err ("can't resubmit intr, %s-%s/input0, status %d",
+		err_hid ("can't resubmit intr, %s-%s/input0, status %d",
 				kbd->usbdev->bus->bus_name,
 				kbd->usbdev->devpath, i);
 }
@@ -151,7 +151,7 @@
 	*(kbd->leds) = kbd->newleds;
 	kbd->led->dev = kbd->usbdev;
 	if (usb_submit_urb(kbd->led, GFP_ATOMIC))
-		err("usb_submit_urb(leds) failed");
+		err_hid("usb_submit_urb(leds) failed");
 
 	return 0;
 }
@@ -169,7 +169,7 @@
 	*(kbd->leds) = kbd->newleds;
 	kbd->led->dev = kbd->usbdev;
 	if (usb_submit_urb(kbd->led, GFP_ATOMIC))
-		err("usb_submit_urb(leds) failed");
+		err_hid("usb_submit_urb(leds) failed");
 }
 
 static int usb_kbd_open(struct input_dev *dev)
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 827ee74..eb53d9a 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -488,6 +488,11 @@
 #define IS_INPUT_APPLICATION(a) (((a >= 0x00010000) && (a <= 0x00010008)) || (a == 0x00010080) || (a == 0x000c0001))
 
 /* HID core API */
+
+#ifdef CONFIG_HID_DEBUG
+extern int hid_debug;
+#endif
+
 extern void hidinput_hid_event(struct hid_device *, struct hid_field *, struct hid_usage *, __s32);
 extern void hidinput_report_event(struct hid_device *hid, struct hid_report *report);
 extern int hidinput_connect(struct hid_device *);
@@ -523,14 +528,19 @@
 #else
 static inline int hid_ff_init(struct hid_device *hid) { return -1; }
 #endif
-#ifdef DEBUG
-#define dbg(format, arg...) printk(KERN_DEBUG "%s: " format "\n" , \
-		__FILE__ , ## arg)
+
+#ifdef CONFIG_HID_DEBUG
+#define dbg_hid(format, arg...) if (hid_debug) \
+				printk(KERN_DEBUG "%s: " format ,\
+				__FILE__ , ## arg)
+#define dbg_hid_line(format, arg...) if (hid_debug) \
+				printk(format, ## arg)
 #else
-#define dbg(format, arg...) do {} while (0)
+#define dbg_hid(format, arg...) do {} while (0)
+#define dbg_hid_line dbg_hid
 #endif
 
-#define err(format, arg...) printk(KERN_ERR "%s: " format "\n" , \
+#define err_hid(format, arg...) printk(KERN_ERR "%s: " format "\n" , \
 		__FILE__ , ## arg)
 #endif