Merge branches 'upstream', 'upstream-fixes' and 'debugfs' into for-linus
diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index aba8fac..111afbe 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -31,21 +31,6 @@
 
 	  If unsure, say Y.
 
-config HID_DEBUG
-	bool "HID debugging support"
-	default y
-	depends on HID
-	---help---
-	This option lets the HID layer output diagnostics about its internal
-	state, resolve HID usages, dump HID fields, etc. Individual HID drivers
-	use this debugging facility to output information about individual HID
-	devices, etc.
-
-	This feature is useful for those who are either debugging the HID parser
-	or any HID hardware device.
-
-	If unsure, say Y.
-
 config HIDRAW
 	bool "/dev/hidraw raw HID device support"
 	depends on HID
diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
index 9b9271d..0de2dff 100644
--- a/drivers/hid/Makefile
+++ b/drivers/hid/Makefile
@@ -3,9 +3,12 @@
 #
 hid-objs			:= hid-core.o hid-input.o
 
+ifdef CONFIG_DEBUG_FS
+	hid-objs		+= hid-debug.o
+endif
+
 obj-$(CONFIG_HID)		+= hid.o
 
-hid-$(CONFIG_HID_DEBUG)		+= hid-debug.o
 hid-$(CONFIG_HIDRAW)		+= hidraw.o
 
 hid-logitech-objs		:= hid-lg.o
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 48567d8..342b7d3 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -44,12 +44,10 @@
 #define DRIVER_DESC "HID core driver"
 #define DRIVER_LICENSE "GPL"
 
-#ifdef CONFIG_HID_DEBUG
 int hid_debug = 0;
 module_param_named(debug, hid_debug, int, 0600);
-MODULE_PARM_DESC(debug, "HID debugging (0=off, 1=probing info, 2=continuous data dumping)");
+MODULE_PARM_DESC(debug, "toggle HID debugging messages");
 EXPORT_SYMBOL_GPL(hid_debug);
-#endif
 
 /*
  * Register a new report for a device.
@@ -861,7 +859,7 @@
 	struct hid_driver *hdrv = hid->driver;
 	int ret;
 
-	hid_dump_input(usage, value);
+	hid_dump_input(hid, usage, value);
 
 	if (hdrv && hdrv->event && hid_match_usage(hid, usage)) {
 		ret = hdrv->event(hid, field, usage, value);
@@ -983,11 +981,10 @@
 {
 	unsigned size = field->report_size;
 
-	hid_dump_input(field->usage + offset, value);
+	hid_dump_input(field->report->device, field->usage + offset, value);
 
 	if (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) {
@@ -1078,6 +1075,7 @@
 	struct hid_report_enum *report_enum;
 	struct hid_driver *hdrv;
 	struct hid_report *report;
+	char *buf;
 	unsigned int i;
 	int ret;
 
@@ -1091,18 +1089,38 @@
 		return -1;
 	}
 
-	dbg_hid("report (size %u) (%snumbered)\n", size, report_enum->numbered ? "" : "un");
+	buf = kmalloc(sizeof(char) * HID_DEBUG_BUFSIZE,
+			interrupt ? GFP_ATOMIC : GFP_KERNEL);
+
+	if (!buf) {
+		report = hid_get_report(report_enum, data);
+		goto nomem;
+	}
+
+	snprintf(buf, HID_DEBUG_BUFSIZE - 1,
+			"\nreport (size %u) (%snumbered)\n", size, report_enum->numbered ? "" : "un");
+	hid_debug_event(hid, buf);
 
 	report = hid_get_report(report_enum, data);
-	if (!report)
+	if (!report) {
+		kfree(buf);
 		return -1;
+	}
 
 	/* dump the report */
-	dbg_hid("report %d (size %u) = ", report->id, size);
-	for (i = 0; i < size; i++)
-		dbg_hid_line(" %02x", data[i]);
-	dbg_hid_line("\n");
+	snprintf(buf, HID_DEBUG_BUFSIZE - 1,
+			"report %d (size %u) = ", report->id, size);
+	hid_debug_event(hid, buf);
+	for (i = 0; i < size; i++) {
+		snprintf(buf, HID_DEBUG_BUFSIZE - 1,
+				" %02x", data[i]);
+		hid_debug_event(hid, buf);
+	}
+	hid_debug_event(hid, "\n");
 
+	kfree(buf);
+
+nomem:
 	if (hdrv && hdrv->raw_event && hid_match_report(hid, report)) {
 		ret = hdrv->raw_event(hid, report, data, size);
 		if (ret != 0)
@@ -1323,7 +1341,6 @@
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ZEROPLUS, 0x0005) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ZEROPLUS, 0x0030) },
 
-	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_APPLE, 0x030c) },
 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_MICROSOFT, USB_DEVICE_ID_MS_PRESENTER_8K_BT) },
 	{ }
 };
@@ -1730,6 +1747,8 @@
 	if (!ret)
 		hdev->status |= HID_STAT_ADDED;
 
+	hid_debug_register(hdev, dev_name(&hdev->dev));
+
 	return ret;
 }
 EXPORT_SYMBOL_GPL(hid_add_device);
@@ -1766,6 +1785,9 @@
 	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);
+
 	return hdev;
 err:
 	put_device(&hdev->dev);
@@ -1777,6 +1799,7 @@
 {
 	if (hdev->status & HID_STAT_ADDED) {
 		device_del(&hdev->dev);
+		hid_debug_unregister(hdev);
 		hdev->status &= ~HID_STAT_ADDED;
 	}
 }
@@ -1852,6 +1875,10 @@
 {
 	int ret;
 
+	if (hid_debug)
+		printk(KERN_WARNING "HID: hid_debug is now used solely for parser and driver debugging.\n"
+				"HID: debugfs is now used for inspecting the device (report descriptor, reports)\n");
+
 	ret = bus_register(&hid_bus_type);
 	if (ret) {
 		printk(KERN_ERR "HID: can't register hid bus\n");
@@ -1862,6 +1889,8 @@
 	if (ret)
 		goto err_bus;
 
+	hid_debug_init();
+
 	return 0;
 err_bus:
 	bus_unregister(&hid_bus_type);
@@ -1871,6 +1900,7 @@
 
 static void __exit hid_exit(void)
 {
+	hid_debug_exit();
 	hidraw_exit();
 	bus_unregister(&hid_bus_type);
 }
diff --git a/drivers/hid/hid-debug.c b/drivers/hid/hid-debug.c
index 04359ed..6abd036 100644
--- a/drivers/hid/hid-debug.c
+++ b/drivers/hid/hid-debug.c
@@ -1,9 +1,9 @@
 /*
  *  (c) 1999 Andreas Gal		<gal@cs.uni-magdeburg.de>
  *  (c) 2000-2001 Vojtech Pavlik	<vojtech@ucw.cz>
- *  (c) 2007 Jiri Kosina
+ *  (c) 2007-2009 Jiri Kosina
  *
- *  Some debug stuff for the HID parser.
+ *  HID debugging support
  */
 
 /*
@@ -26,9 +26,17 @@
  * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
  */
 
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/sched.h>
+#include <linux/uaccess.h>
+#include <linux/poll.h>
+
 #include <linux/hid.h>
 #include <linux/hid-debug.h>
 
+static struct dentry *hid_debug_root;
+
 struct hid_usage_entry {
 	unsigned  page;
 	unsigned  usage;
@@ -339,72 +347,120 @@
   { 0, 0, NULL }
 };
 
-static void resolv_usage_page(unsigned page) {
+/* Either output directly into simple seq_file, or (if f == NULL)
+ * allocate a separate buffer that will then be passed to the 'events'
+ * ringbuffer.
+ *
+ * This is because these functions can be called both for "one-shot"
+ * "rdesc" while resolving, or for blocking "events".
+ *
+ * This holds both for resolv_usage_page() and hid_resolv_usage().
+ */
+static char *resolv_usage_page(unsigned page, struct seq_file *f) {
 	const struct hid_usage_entry *p;
+	char *buf = NULL;
+
+	if (!f) {
+		buf = kzalloc(sizeof(char) * HID_DEBUG_BUFSIZE, GFP_ATOMIC);
+		if (!buf)
+			return ERR_PTR(-ENOMEM);
+	}
 
 	for (p = hid_usage_table; p->description; p++)
 		if (p->page == page) {
-			printk("%s", p->description);
-			return;
+			if (!f) {
+				snprintf(buf, HID_DEBUG_BUFSIZE, "%s",
+						p->description);
+				return buf;
+			}
+			else {
+				seq_printf(f, "%s", p->description);
+				return NULL;
+			}
 		}
-	printk("%04x", page);
+	if (!f)
+		snprintf(buf, HID_DEBUG_BUFSIZE, "%04x", page);
+	else
+		seq_printf(f, "%04x", page);
+	return buf;
 }
 
-void hid_resolv_usage(unsigned usage) {
+char *hid_resolv_usage(unsigned usage, struct seq_file *f) {
 	const struct hid_usage_entry *p;
+	char *buf = NULL;
+	int len = 0;
 
-	if (!hid_debug)
-		return;
+	buf = resolv_usage_page(usage >> 16, f);
+	if (IS_ERR(buf)) {
+		printk(KERN_ERR "error allocating HID debug buffer\n");
+		return NULL;
+	}
 
-	resolv_usage_page(usage >> 16);
-	printk(".");
+
+	if (!f) {
+		len = strlen(buf);
+		snprintf(buf+len, max(0, HID_DEBUG_BUFSIZE - len), ".");
+		len++;
+	}
+	else {
+		seq_printf(f, ".");
+	}
 	for (p = hid_usage_table; p->description; p++)
 		if (p->page == (usage >> 16)) {
 			for(++p; p->description && p->usage != 0; p++)
 				if (p->usage == (usage & 0xffff)) {
-					printk("%s", p->description);
-					return;
+					if (!f)
+						snprintf(buf + len,
+							max(0,HID_DEBUG_BUFSIZE - len - 1),
+							"%s", p->description);
+					else
+						seq_printf(f,
+							"%s",
+							p->description);
+					return buf;
 				}
 			break;
 		}
-	printk("%04x", usage & 0xffff);
+	if (!f)
+		snprintf(buf + len, max(0, HID_DEBUG_BUFSIZE - len - 1),
+				"%04x", usage & 0xffff);
+	else
+		seq_printf(f, "%04x", usage & 0xffff);
+	return buf;
 }
 EXPORT_SYMBOL_GPL(hid_resolv_usage);
 
-static void tab(int n) {
-	printk(KERN_DEBUG "%*s", n, "");
+static void tab(int n, struct seq_file *f) {
+	seq_printf(f, "%*s", n, "");
 }
 
-void hid_dump_field(struct hid_field *field, int n) {
+void hid_dump_field(struct hid_field *field, int n, struct seq_file *f) {
 	int j;
 
-	if (!hid_debug)
-		return;
-
 	if (field->physical) {
-		tab(n);
-		printk("Physical(");
-		hid_resolv_usage(field->physical); printk(")\n");
+		tab(n, f);
+		seq_printf(f, "Physical(");
+		hid_resolv_usage(field->physical, f); seq_printf(f, ")\n");
 	}
 	if (field->logical) {
-		tab(n);
-		printk("Logical(");
-		hid_resolv_usage(field->logical); printk(")\n");
+		tab(n, f);
+		seq_printf(f, "Logical(");
+		hid_resolv_usage(field->logical, f); seq_printf(f, ")\n");
 	}
-	tab(n); printk("Usage(%d)\n", field->maxusage);
+	tab(n, f); seq_printf(f, "Usage(%d)\n", field->maxusage);
 	for (j = 0; j < field->maxusage; j++) {
-		tab(n+2); hid_resolv_usage(field->usage[j].hid); printk("\n");
+		tab(n+2, f); hid_resolv_usage(field->usage[j].hid, f); seq_printf(f, "\n");
 	}
 	if (field->logical_minimum != field->logical_maximum) {
-		tab(n); printk("Logical Minimum(%d)\n", field->logical_minimum);
-		tab(n); printk("Logical Maximum(%d)\n", field->logical_maximum);
+		tab(n, f); seq_printf(f, "Logical Minimum(%d)\n", field->logical_minimum);
+		tab(n, f); seq_printf(f, "Logical Maximum(%d)\n", field->logical_maximum);
 	}
 	if (field->physical_minimum != field->physical_maximum) {
-		tab(n); printk("Physical Minimum(%d)\n", field->physical_minimum);
-		tab(n); printk("Physical Maximum(%d)\n", field->physical_maximum);
+		tab(n, f); seq_printf(f, "Physical Minimum(%d)\n", field->physical_minimum);
+		tab(n, f); seq_printf(f, "Physical Maximum(%d)\n", field->physical_maximum);
 	}
 	if (field->unit_exponent) {
-		tab(n); printk("Unit Exponent(%d)\n", field->unit_exponent);
+		tab(n, f); seq_printf(f, "Unit Exponent(%d)\n", field->unit_exponent);
 	}
 	if (field->unit) {
 		static const char *systems[5] = { "None", "SI Linear", "SI Rotation", "English Linear", "English Rotation" };
@@ -425,77 +481,75 @@
 		data >>= 4;
 
 		if(sys > 4) {
-			tab(n); printk("Unit(Invalid)\n");
+			tab(n, f); seq_printf(f, "Unit(Invalid)\n");
 		}
 		else {
 			int earlier_unit = 0;
 
-			tab(n); printk("Unit(%s : ", systems[sys]);
+			tab(n, f); seq_printf(f, "Unit(%s : ", systems[sys]);
 
 			for (i=1 ; i<sizeof(__u32)*2 ; i++) {
 				char nibble = data & 0xf;
 				data >>= 4;
 				if (nibble != 0) {
 					if(earlier_unit++ > 0)
-						printk("*");
-					printk("%s", units[sys][i]);
+						seq_printf(f, "*");
+					seq_printf(f, "%s", units[sys][i]);
 					if(nibble != 1) {
 						/* This is a _signed_ nibble(!) */
 
 						int val = nibble & 0x7;
 						if(nibble & 0x08)
 							val = -((0x7 & ~val) +1);
-						printk("^%d", val);
+						seq_printf(f, "^%d", val);
 					}
 				}
 			}
-			printk(")\n");
+			seq_printf(f, ")\n");
 		}
 	}
-	tab(n); printk("Report Size(%u)\n", field->report_size);
-	tab(n); printk("Report Count(%u)\n", field->report_count);
-	tab(n); printk("Report Offset(%u)\n", field->report_offset);
+	tab(n, f); seq_printf(f, "Report Size(%u)\n", field->report_size);
+	tab(n, f); seq_printf(f, "Report Count(%u)\n", field->report_count);
+	tab(n, f); seq_printf(f, "Report Offset(%u)\n", field->report_offset);
 
-	tab(n); printk("Flags( ");
+	tab(n, f); seq_printf(f, "Flags( ");
 	j = field->flags;
-	printk("%s", HID_MAIN_ITEM_CONSTANT & j ? "Constant " : "");
-	printk("%s", HID_MAIN_ITEM_VARIABLE & j ? "Variable " : "Array ");
-	printk("%s", HID_MAIN_ITEM_RELATIVE & j ? "Relative " : "Absolute ");
-	printk("%s", HID_MAIN_ITEM_WRAP & j ? "Wrap " : "");
-	printk("%s", HID_MAIN_ITEM_NONLINEAR & j ? "NonLinear " : "");
-	printk("%s", HID_MAIN_ITEM_NO_PREFERRED & j ? "NoPreferredState " : "");
-	printk("%s", HID_MAIN_ITEM_NULL_STATE & j ? "NullState " : "");
-	printk("%s", HID_MAIN_ITEM_VOLATILE & j ? "Volatile " : "");
-	printk("%s", HID_MAIN_ITEM_BUFFERED_BYTE & j ? "BufferedByte " : "");
-	printk(")\n");
+	seq_printf(f, "%s", HID_MAIN_ITEM_CONSTANT & j ? "Constant " : "");
+	seq_printf(f, "%s", HID_MAIN_ITEM_VARIABLE & j ? "Variable " : "Array ");
+	seq_printf(f, "%s", HID_MAIN_ITEM_RELATIVE & j ? "Relative " : "Absolute ");
+	seq_printf(f, "%s", HID_MAIN_ITEM_WRAP & j ? "Wrap " : "");
+	seq_printf(f, "%s", HID_MAIN_ITEM_NONLINEAR & j ? "NonLinear " : "");
+	seq_printf(f, "%s", HID_MAIN_ITEM_NO_PREFERRED & j ? "NoPreferredState " : "");
+	seq_printf(f, "%s", HID_MAIN_ITEM_NULL_STATE & j ? "NullState " : "");
+	seq_printf(f, "%s", HID_MAIN_ITEM_VOLATILE & j ? "Volatile " : "");
+	seq_printf(f, "%s", HID_MAIN_ITEM_BUFFERED_BYTE & j ? "BufferedByte " : "");
+	seq_printf(f, ")\n");
 }
 EXPORT_SYMBOL_GPL(hid_dump_field);
 
-void hid_dump_device(struct hid_device *device) {
+void hid_dump_device(struct hid_device *device, struct seq_file *f)
+{
 	struct hid_report_enum *report_enum;
 	struct hid_report *report;
 	struct list_head *list;
 	unsigned i,k;
 	static const 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;
 		while (list != &report_enum->report_list) {
 			report = (struct hid_report *) list;
-			tab(2);
-			printk("%s", table[i]);
+			tab(2, f);
+			seq_printf(f, "%s", table[i]);
 			if (report->id)
-				printk("(%d)", report->id);
-			printk("[%s]", table[report->type]);
-			printk("\n");
+				seq_printf(f, "(%d)", report->id);
+			seq_printf(f, "[%s]", table[report->type]);
+			seq_printf(f, "\n");
 			for (k = 0; k < report->maxfield; k++) {
-				tab(4);
-				printk("Field(%d)\n", k);
-				hid_dump_field(report->field[k], 6);
+				tab(4, f);
+				seq_printf(f, "Field(%d)\n", k);
+				hid_dump_field(report->field[k], 6, f);
 			}
 			list = list->next;
 		}
@@ -503,13 +557,37 @@
 }
 EXPORT_SYMBOL_GPL(hid_dump_device);
 
-void hid_dump_input(struct hid_usage *usage, __s32 value) {
-	if (hid_debug < 2)
-		return;
+/* enqueue string to 'events' ring buffer */
+void hid_debug_event(struct hid_device *hdev, char *buf)
+{
+	int i;
+	struct hid_debug_list *list;
 
-	printk(KERN_DEBUG "hid-debug: input ");
-	hid_resolv_usage(usage->hid);
-	printk(" = %d\n", value);
+	list_for_each_entry(list, &hdev->debug_list, node) {
+		for (i = 0; i <= strlen(buf); i++)
+			list->hid_debug_buf[(list->tail + i) % (HID_DEBUG_BUFSIZE - 1)] =
+				buf[i];
+		list->tail = (list->tail + i) % (HID_DEBUG_BUFSIZE - 1);
+        }
+}
+EXPORT_SYMBOL_GPL(hid_debug_event);
+
+void hid_dump_input(struct hid_device *hdev, struct hid_usage *usage, __s32 value)
+{
+	char *buf;
+	int len;
+
+	buf = hid_resolv_usage(usage->hid, NULL);
+	if (!buf)
+		return;
+	len = strlen(buf);
+	snprintf(buf + len, HID_DEBUG_BUFSIZE - len - 1, " = %d\n", value);
+
+	hid_debug_event(hdev, buf);
+
+	kfree(buf);
+        wake_up_interruptible(&hdev->debug_wait);
+
 }
 EXPORT_SYMBOL_GPL(hid_dump_input);
 
@@ -786,12 +864,221 @@
 	[EV_SND] = sounds,			[EV_REP] = repeats,
 };
 
-void hid_resolv_event(__u8 type, __u16 code) {
+void hid_resolv_event(__u8 type, __u16 code, struct seq_file *f) {
 
-	if (!hid_debug)
-		return;
-
-	printk("%s.%s", events[type] ? events[type] : "?",
+	seq_printf(f, "%s.%s", events[type] ? events[type] : "?",
 		names[type] ? (names[type][code] ? names[type][code] : "?") : "?");
 }
-EXPORT_SYMBOL_GPL(hid_resolv_event);
+
+void hid_dump_input_mapping(struct hid_device *hid, struct seq_file *f)
+{
+	int i, j, k;
+	struct hid_report *report;
+	struct hid_usage *usage;
+
+	for (k = HID_INPUT_REPORT; k <= HID_OUTPUT_REPORT; k++) {
+		list_for_each_entry(report, &hid->report_enum[k].report_list, list) {
+			for (i = 0; i < report->maxfield; i++) {
+				for ( j = 0; j < report->field[i]->maxusage; j++) {
+					usage = report->field[i]->usage + j;
+					hid_resolv_usage(usage->hid, f);
+					seq_printf(f, " ---> ");
+					hid_resolv_event(usage->type, usage->code, f);
+					seq_printf(f, "\n");
+				}
+			}
+		}
+	}
+
+}
+
+
+static int hid_debug_rdesc_show(struct seq_file *f, void *p)
+{
+	struct hid_device *hdev = f->private;
+	int i;
+
+	/* dump HID report descriptor */
+	for (i = 0; i < hdev->rsize; i++)
+		seq_printf(f, "%02x ", hdev->rdesc[i]);
+	seq_printf(f, "\n\n");
+
+	/* dump parsed data and input mappings */
+	hid_dump_device(hdev, f);
+	seq_printf(f, "\n");
+	hid_dump_input_mapping(hdev, f);
+
+	return 0;
+}
+
+static int hid_debug_rdesc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, hid_debug_rdesc_show, inode->i_private);
+}
+
+static int hid_debug_events_open(struct inode *inode, struct file *file)
+{
+	int err = 0;
+	struct hid_debug_list *list;
+
+	if (!(list = kzalloc(sizeof(struct hid_debug_list), GFP_KERNEL))) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	if (!(list->hid_debug_buf = kzalloc(sizeof(char) * HID_DEBUG_BUFSIZE, GFP_KERNEL))) {
+		err = -ENOMEM;
+		kfree(list);
+		goto out;
+	}
+	list->hdev = (struct hid_device *) inode->i_private;
+	file->private_data = list;
+	mutex_init(&list->read_mutex);
+
+	list_add_tail(&list->node, &list->hdev->debug_list);
+
+out:
+	return err;
+}
+
+static ssize_t hid_debug_events_read(struct file *file, char __user *buffer,
+		size_t count, loff_t *ppos)
+{
+	struct hid_debug_list *list = file->private_data;
+	int ret = 0, len;
+	DECLARE_WAITQUEUE(wait, current);
+
+	while (ret == 0) {
+		mutex_lock(&list->read_mutex);
+		if (list->head == list->tail) {
+			add_wait_queue(&list->hdev->debug_wait, &wait);
+			set_current_state(TASK_INTERRUPTIBLE);
+
+			while (list->head == list->tail) {
+				if (file->f_flags & O_NONBLOCK) {
+					ret = -EAGAIN;
+					break;
+				}
+				if (signal_pending(current)) {
+					ret = -ERESTARTSYS;
+					break;
+				}
+
+				if (!list->hdev || !list->hdev->debug) {
+					ret = -EIO;
+					break;
+				}
+
+				/* allow O_NONBLOCK from other threads */
+				mutex_unlock(&list->read_mutex);
+				schedule();
+				mutex_lock(&list->read_mutex);
+				set_current_state(TASK_INTERRUPTIBLE);
+			}
+
+			set_current_state(TASK_RUNNING);
+			remove_wait_queue(&list->hdev->debug_wait, &wait);
+		}
+
+		if (ret)
+			goto out;
+
+		/* pass the ringbuffer contents to userspace */
+copy_rest:
+		if (list->tail == list->head)
+			goto out;
+		if (list->tail > list->head) {
+			len = list->tail - list->head;
+
+			if (copy_to_user(buffer + ret, &list->hid_debug_buf[list->head], len)) {
+				ret = -EFAULT;
+				goto out;
+			}
+			ret += len;
+			list->head += len;
+		} else {
+			len = HID_DEBUG_BUFSIZE - list->head;
+
+			if (copy_to_user(buffer, &list->hid_debug_buf[list->head], len)) {
+				ret = -EFAULT;
+				goto out;
+			}
+			list->head = 0;
+			ret += len;
+			goto copy_rest;
+		}
+
+	}
+out:
+	mutex_unlock(&list->read_mutex);
+	return ret;
+}
+
+static unsigned int hid_debug_events_poll(struct file *file, poll_table *wait)
+{
+	struct hid_debug_list *list = file->private_data;
+
+	poll_wait(file, &list->hdev->debug_wait, wait);
+	if (list->head != list->tail)
+		return POLLIN | POLLRDNORM;
+	if (!list->hdev->debug)
+		return POLLERR | POLLHUP;
+	return 0;
+}
+
+static int hid_debug_events_release(struct inode *inode, struct file *file)
+{
+	struct hid_debug_list *list = file->private_data;
+
+	list_del(&list->node);
+	kfree(list->hid_debug_buf);
+	kfree(list);
+
+	return 0;
+}
+
+static const struct file_operations hid_debug_rdesc_fops = {
+	.open           = hid_debug_rdesc_open,
+	.read           = seq_read,
+	.llseek         = seq_lseek,
+	.release        = single_release,
+};
+
+static const struct file_operations hid_debug_events_fops = {
+	.owner =        THIS_MODULE,
+	.open           = hid_debug_events_open,
+	.read           = hid_debug_events_read,
+	.poll		= hid_debug_events_poll,
+	.release        = hid_debug_events_release,
+};
+
+
+void hid_debug_register(struct hid_device *hdev, const char *name)
+{
+	hdev->debug_dir = debugfs_create_dir(name, hid_debug_root);
+	hdev->debug_rdesc = debugfs_create_file("rdesc", 0400,
+			hdev->debug_dir, hdev, &hid_debug_rdesc_fops);
+	hdev->debug_events = debugfs_create_file("events", 0400,
+			hdev->debug_dir, hdev, &hid_debug_events_fops);
+	hdev->debug = 1;
+}
+
+void hid_debug_unregister(struct hid_device *hdev)
+{
+	hdev->debug = 0;
+	wake_up_interruptible(&hdev->debug_wait);
+	debugfs_remove(hdev->debug_rdesc);
+	debugfs_remove(hdev->debug_events);
+	debugfs_remove(hdev->debug_dir);
+}
+
+void hid_debug_init(void)
+{
+	hid_debug_root = debugfs_create_dir("hid", NULL);
+}
+
+void hid_debug_exit(void)
+{
+	debugfs_remove_recursive(hid_debug_root);
+}
+
diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index 7f183b7..5862b0f 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -159,17 +159,12 @@
 
 	field->hidinput = hidinput;
 
-	dbg_hid("Mapping: ");
-	hid_resolv_usage(usage->hid);
-	dbg_hid_line(" ---> ");
-
 	if (field->flags & HID_MAIN_ITEM_CONSTANT)
 		goto ignore;
 
 	/* only LED usages are supported in output fields */
 	if (field->report_type == HID_OUTPUT_REPORT &&
 			(usage->hid & HID_USAGE_PAGE) != HID_UP_LED) {
-		dbg_hid_line(" [non-LED output field] ");
 		goto ignore;
 	}
 
@@ -561,15 +556,9 @@
 		set_bit(MSC_SCAN, input->mscbit);
 	}
 
-	hid_resolv_event(usage->type, usage->code);
-
-	dbg_hid_line("\n");
-
-	return;
-
 ignore:
-	dbg_hid_line("IGNORED\n");
 	return;
+
 }
 
 void hidinput_hid_event(struct hid_device *hid, struct hid_field *field, struct hid_usage *usage, __s32 value)
diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index 25f38a5..1b0e07a 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -4,8 +4,8 @@
  *  Copyright (c) 1999 Andreas Gal
  *  Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
  *  Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
- *  Copyright (c) 2006-2008 Jiri Kosina
  *  Copyright (c) 2007-2008 Oliver Neukum
+ *  Copyright (c) 2006-2009 Jiri Kosina
  */
 
 /*
@@ -886,11 +886,6 @@
 		goto err;
 	}
 
-	dbg_hid("report descriptor (size %u, read %d) = ", rsize, n);
-	for (n = 0; n < rsize; n++)
-		dbg_hid_line(" %02x", (unsigned char) rdesc[n]);
-	dbg_hid_line("\n");
-
 	ret = hid_parse_report(hid, rdesc, rsize);
 	kfree(rdesc);
 	if (ret) {
@@ -1004,7 +999,6 @@
 	usbhid->urbctrl->transfer_flags |= (URB_NO_TRANSFER_DMA_MAP | URB_NO_SETUP_DMA_MAP);
 
 	usbhid_init_reports(hid);
-	hid_dump_device(hid);
 
 	set_bit(HID_STARTED, &usbhid->iofl);
 
diff --git a/drivers/hid/usbhid/hid-quirks.c b/drivers/hid/usbhid/hid-quirks.c
index d8f7423..0d9045a 100644
--- a/drivers/hid/usbhid/hid-quirks.c
+++ b/drivers/hid/usbhid/hid-quirks.c
@@ -201,7 +201,7 @@
 	u32 quirks;
 	int n = 0, m;
 
-	for (; quirks_param[n] && n < MAX_USBHID_BOOT_QUIRKS; n++) {
+	for (; n < MAX_USBHID_BOOT_QUIRKS && quirks_param[n]; n++) {
 
 		m = sscanf(quirks_param[n], "0x%hx:0x%hx:0x%x",
 				&idVendor, &idProduct, &quirks);
diff --git a/include/linux/hid-debug.h b/include/linux/hid-debug.h
index 50d568e..53744fa 100644
--- a/include/linux/hid-debug.h
+++ b/include/linux/hid-debug.h
@@ -2,7 +2,7 @@
 #define __HID_DEBUG_H
 
 /*
- *  Copyright (c) 2007	Jiri Kosina
+ *  Copyright (c) 2007-2009	Jiri Kosina
  */
 
 /*
@@ -22,24 +22,44 @@
  *
  */
 
-#ifdef CONFIG_HID_DEBUG
+#define HID_DEBUG_BUFSIZE 512
 
-void hid_dump_input(struct hid_usage *, __s32);
-void hid_dump_device(struct hid_device *);
-void hid_dump_field(struct hid_field *, int);
-void hid_resolv_usage(unsigned);
-void hid_resolv_event(__u8, __u16);
+#ifdef CONFIG_DEBUG_FS
+
+void hid_dump_input(struct hid_device *, struct hid_usage *, __s32);
+void hid_dump_device(struct hid_device *, struct seq_file *);
+void hid_dump_field(struct hid_field *, int, struct seq_file *);
+char *hid_resolv_usage(unsigned, struct seq_file *);
+void hid_debug_register(struct hid_device *, const char *);
+void hid_debug_unregister(struct hid_device *);
+void hid_debug_init(void);
+void hid_debug_exit(void);
+void hid_debug_event(struct hid_device *, char *);
+
+
+struct hid_debug_list {
+	char *hid_debug_buf;
+	int head;
+	int tail;
+	struct fasync_struct *fasync;
+	struct hid_device *hdev;
+	struct list_head node;
+	struct mutex read_mutex;
+};
 
 #else
 
-#define hid_dump_input(a,b)     do { } while (0)
-#define hid_dump_device(c)      do { } while (0)
-#define hid_dump_field(a,b)     do { } while (0)
-#define hid_resolv_usage(a)         do { } while (0)
-#define hid_resolv_event(a,b)       do { } while (0)
+#define hid_dump_input(a,b,c)		do { } while (0)
+#define hid_dump_device(a,b)		do { } while (0)
+#define hid_dump_field(a,b,c)		do { } while (0)
+#define hid_resolv_usage(a,b)		do { } while (0)
+#define hid_debug_register(a, b)	do { } while (0)
+#define hid_debug_unregister(a)		do { } while (0)
+#define hid_debug_init()		do { } while (0)
+#define hid_debug_exit()		do { } while (0)
+#define hid_debug_event(a,b)		do { } while (0)
 
-#endif /* CONFIG_HID_DEBUG */
-
+#endif
 
 #endif
 
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 53489fd..a0ebdac 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -500,6 +500,14 @@
 
 	/* handler for raw output data, used by hidraw */
 	int (*hid_output_raw_report) (struct hid_device *, __u8 *, size_t);
+
+	/* debugging support via debugfs */
+	unsigned short debug;
+	struct dentry *debug_dir;
+	struct dentry *debug_rdesc;
+	struct dentry *debug_events;
+	struct list_head debug_list;
+	wait_queue_head_t debug_wait;
 };
 
 static inline void *hid_get_drvdata(struct hid_device *hdev)
@@ -657,9 +665,7 @@
 
 /* HID core API */
 
-#ifdef CONFIG_HID_DEBUG
 extern int hid_debug;
-#endif
 
 extern int hid_add_device(struct hid_device *);
 extern void hid_destroy_device(struct hid_device *);
@@ -815,21 +821,9 @@
 #define hid_pidff_init NULL
 #endif
 
-#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
-static inline int __attribute__((format(printf, 1, 2)))
-dbg_hid(const char *fmt, ...)
-{
-	return 0;
-}
-#define dbg_hid_line dbg_hid
-#endif /* HID_DEBUG */
-
 #define err_hid(format, arg...) printk(KERN_ERR "%s: " format "\n" , \
 		__FILE__ , ## arg)
 #endif /* HID_FF */