patch-2.3.36 linux/drivers/usb/hid.c

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diff -u --recursive --new-file v2.3.35/linux/drivers/usb/hid.c linux/drivers/usb/hid.c
@@ -0,0 +1,1201 @@
+/*
+ *  hid.c  Version 0.8
+ *
+ *  Copyright (c) 1999 Andreas Gal
+ *  Copyright (c) 1999 Vojtech Pavlik
+ *
+ *  USB HID support for the Linux input drivers
+ *
+ *  Sponsored by SuSE
+ */
+
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or 
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * 
+ * Should you need to contact me, the author, you can do so either by
+ * e-mail - mail your message to <vojtech@suse.cz>, or by paper mail:
+ * Vojtech Pavlik, Ucitelska 1576, Prague 8, 182 00 Czech Republic
+ */
+
+#include <linux/module.h>
+#include <linux/malloc.h>
+#include <linux/input.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/list.h>
+#include <linux/mm.h>
+#include <linux/smp_lock.h>
+#include <linux/config.h>
+#include <linux/input.h>
+#include <linux/spinlock.h>
+#include <linux/list.h>
+
+#include "usb.h"
+#include "hid.h"
+
+#ifdef CONFIG_USB_HID_DEBUG_LOTS
+#include "hid-debug.h"
+#else
+#define hid_dump_input(a,b)	do { } while (0)
+#define hid_dump_device(c)	do { } while (0)
+#endif
+
+static unsigned char hid_keyboard[256] = {
+	  0,  0,  0,  0, 30, 48, 46, 32, 18, 33, 34, 35, 23, 36, 37, 38,
+	 50, 49, 24, 25, 16, 19, 31, 20, 22, 47, 17, 45, 21, 44,  2,  3,
+	  4,  5,  6,  7,  8,  9, 10, 11, 28,  1, 14, 15, 57, 12, 13, 26,
+	 27, 43,192, 39, 40, 41, 51, 52, 53, 58, 59, 60, 61, 62, 63, 64,
+	 65, 66, 67, 68, 87, 88, 99, 70,119,110,102,104,111,107,109,106,
+	105,108,103, 69, 98, 55, 74, 78, 96, 79, 80, 81, 75, 76, 77, 71,
+	 72, 73, 82, 83, 86,127,116,117, 85, 89, 90, 91, 92, 93, 94, 95,
+	120,121,122,123,192,138,192,192,128,129,131,137,133,135,136,113,
+	115,114,192,192,192,192,192,124,192,192,192,192,192,192,192,192,
+	192,192,192,192,192,192,192,192,192,192,192,192,192,192,192,192,
+	192,192,192,192,192,192,192,192,192,192,192,192,192,192,192,192,
+	192,192,192,192,192,192,192,192,192,192,192,192,192,192,192,192,
+	192,192,192,192,192,192,192,192,192,192,192,192,192,192,192,192,
+	192,192,192,192,192,192,192,192,192,192,192,192,192,192,192,192,
+	 29, 42, 56,125, 97, 54,100,126
+};
+
+static struct {
+	__s32 x;
+	__s32 y;
+}  hid_hat_to_axis[] = {{ 0, 0}, { 0,-1}, { 1,-1}, { 1, 0}, { 1, 1}, { 0, 1}, {-1, 1}, {-1, 0}, {-1,-1}};
+
+/*
+ * Register a new report for a device.
+ */
+
+static struct hid_report *hid_register_report(struct hid_device *device, unsigned type, unsigned id)
+{
+	struct hid_report_enum *report_enum = device->report_enum + type;
+	struct hid_report *report;
+	 
+	if (report_enum->report_id_hash[id])
+		return report_enum->report_id_hash[id];
+
+	if (!(report = kmalloc(sizeof(struct hid_report), GFP_KERNEL)))
+		return NULL;
+	memset(report, 0, sizeof(struct hid_report));
+
+	if (id != 0) report_enum->numbered = 1;
+
+	report->id = id;
+	report->type = type;
+	report->size = 0;
+	report->device = device;
+	report_enum->report_id_hash[id] = report;
+
+	list_add_tail(&report->list, &report_enum->report_list);
+
+	return report;
+}
+
+/*
+ * Register a new field for this report.
+ */
+
+static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages, unsigned values)
+{
+	if (report->maxfield < HID_MAX_FIELDS) {
+		struct hid_field *field;
+
+		if (!(field = kmalloc(sizeof(struct hid_field) + usages * sizeof(struct hid_usage)
+				+ values * sizeof(unsigned), GFP_KERNEL)))
+			return NULL;
+		memset(field, 0, sizeof(struct hid_field) + usages * sizeof(struct hid_usage)
+				+ values * sizeof(unsigned));
+
+		report->field[report->maxfield++] = field;
+		field->usage = (struct hid_usage *)(field + 1);
+		field->value = (unsigned *)(field->usage + usages);
+		field->report = report;
+
+		return field;
+	}
+
+	hid_debug("too many fields in report");
+	return NULL;
+}
+
+/*
+ * Open a collection. The type/usage is pushed on the stack.
+ */
+
+static int open_collection(struct hid_parser *parser, unsigned type)
+{
+	unsigned usage;
+
+	usage = parser->local.usage[0];
+
+	if (type == HID_COLLECTION_APPLICATION)
+		parser->device->application = usage;
+
+	if (parser->collection_stack_ptr < HID_COLLECTION_STACK_SIZE) { /* PUSH on stack */
+		struct hid_collection *collection = parser->collection_stack + parser->collection_stack_ptr++;
+		collection->type = type;
+		collection->usage = usage;
+		return 0;
+	}
+
+	hid_debug("collection stack overflow");
+	return -1;
+}
+
+/*
+ * Close a collection.
+ */
+
+static int close_collection(struct hid_parser *parser)
+{
+	if (parser->collection_stack_ptr > 0) {	/* POP from stack */
+		parser->collection_stack_ptr--;
+		return 0;
+	}
+	hid_debug("collection stack underflow");
+	return -1;
+}
+
+/*
+ * Climb up the stack, search for the specified collection type
+ * and return the usage.
+ */
+
+static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type)
+{
+	int n;
+	for (n = parser->collection_stack_ptr - 1; n >= 0; n--)
+		if (parser->collection_stack[n].type == type)
+			return parser->collection_stack[n].usage;
+	return 0; /* we know nothing about this usage type */
+}
+
+/*
+ * Add a usage to the temporary parser table.
+ */
+
+static int hid_add_usage(struct hid_parser *parser, unsigned usage)
+{
+	if (parser->local.usage_index >= MAX_USAGES) {
+		hid_debug("usage index exceeded");
+		return -1;
+	}
+	parser->local.usage[parser->local.usage_index++] = usage;
+	return 0;
+}
+
+/*
+ * Register a new field for this report.
+ */
+
+static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsigned flags)
+{
+	struct hid_report *report;
+	struct hid_field *field;
+	int usages;
+	unsigned offset;
+	int i;
+
+	if (!(report = hid_register_report(parser->device, report_type, parser->global.report_id))) {
+    		hid_debug("hid_register_report failed");
+		return -1;
+	}
+
+	if (HID_MAIN_ITEM_VARIABLE & ~flags) { /* ARRAY */
+		if (parser->global.logical_maximum <= parser->global.logical_minimum) {
+			hid_debug("logical range invalid %d %d", parser->global.logical_minimum, parser->global.logical_maximum);
+			return -1;
+		}
+		usages = parser->local.usage_index;
+		/* Hint: we can assume usages < MAX_USAGE here */
+	} else { /* VARIABLE */
+		usages = parser->global.report_count;
+	}
+	offset = report->size;
+	report->size += parser->global.report_size *
+			parser->global.report_count;
+	if (usages == 0)
+		return 0; /* ignore padding fields */
+	if ((field = hid_register_field(report, usages,
+			     parser->global.report_count)) == NULL)
+		return 0;
+	field->physical = hid_lookup_collection(parser, HID_COLLECTION_PHYSICAL);
+	field->logical = hid_lookup_collection(parser, HID_COLLECTION_LOGICAL);
+	for (i = 0; i < usages; i++) field->usage[i].hid = parser->local.usage[i];
+	field->maxusage = usages;
+	field->flags = flags;
+	field->report_offset = offset;
+	field->report_type = report_type;
+	field->report_size = parser->global.report_size;
+	field->report_count = parser->global.report_count;
+	field->logical_minimum = parser->global.logical_minimum;
+	field->logical_maximum = parser->global.logical_maximum;
+	field->physical_minimum = parser->global.physical_minimum;
+	field->physical_maximum = parser->global.physical_maximum;
+	field->unit_exponent = parser->global.unit_exponent;
+	field->unit = parser->global.unit;
+	return 0;
+}
+
+/*
+ * Read data value from item.
+ */
+
+static __inline__ __u32 item_udata(struct hid_item *item)
+{
+	switch (item->size) {
+		case 1: return item->data.u8;
+		case 2: return item->data.u16;
+		case 4: return item->data.u32;
+	}
+	return 0;
+}
+
+static __inline__ __s32 item_sdata(struct hid_item *item)
+{
+	switch (item->size) {
+		case 1: return item->data.s8;
+		case 2: return item->data.s16;
+		case 4: return item->data.s32;
+	}
+	return 0;
+}
+
+/*
+ * Process a global item.
+ */
+
+static int hid_parser_global(struct hid_parser *parser, struct hid_item *item)
+{
+	switch (item->tag) {
+
+		case HID_GLOBAL_ITEM_TAG_PUSH:
+
+			if (parser->global_stack_ptr < HID_GLOBAL_STACK_SIZE) {
+				memcpy(parser->global_stack + parser->global_stack_ptr++,
+					&parser->global, sizeof(struct hid_parser));
+				return 0;
+			}
+			hid_debug("global enviroment stack overflow");
+			return -1;
+
+		case HID_GLOBAL_ITEM_TAG_POP:
+
+			if (parser->global_stack_ptr > 0) {
+				memcpy(&parser->global, parser->global_stack + --parser->global_stack_ptr,
+					sizeof(struct hid_parser));
+				return 0;
+			}
+			hid_debug("global enviroment stack underflow");
+			return -1;
+
+		case HID_GLOBAL_ITEM_TAG_USAGE_PAGE:
+			parser->global.usage_page = item_udata(item);
+			return 0;
+
+		case HID_GLOBAL_ITEM_TAG_LOGICAL_MINIMUM:
+			parser->global.logical_minimum = item_sdata(item);
+			return 0;
+
+		case HID_GLOBAL_ITEM_TAG_LOGICAL_MAXIMUM:
+			parser->global.logical_maximum = item_sdata(item);
+			return 0;
+
+		case HID_GLOBAL_ITEM_TAG_PHYSICAL_MINIMUM:
+			parser->global.physical_minimum = item_sdata(item);
+			return 0;
+
+		case HID_GLOBAL_ITEM_TAG_PHYSICAL_MAXIMUM:
+			parser->global.physical_maximum = item_sdata(item);
+			return 0;
+
+		case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT:
+			parser->global.unit_exponent = item_udata(item);
+			return 0;
+
+		case HID_GLOBAL_ITEM_TAG_UNIT:
+			parser->global.unit = item_udata(item);
+			return 0;
+
+		case HID_GLOBAL_ITEM_TAG_REPORT_SIZE:
+			if ((parser->global.report_size = item_udata(item)) > 32) {
+				hid_debug("invalid report_size %d", parser->global.report_size);
+				return -1;
+			}
+			return 0;
+
+		case HID_GLOBAL_ITEM_TAG_REPORT_COUNT:
+			if ((parser->global.report_count = item_udata(item)) > MAX_USAGES) {
+				hid_debug("invalid report_count %d", parser->global.report_count);
+				return -1;
+			}
+			return 0;
+
+		case HID_GLOBAL_ITEM_TAG_REPORT_ID:
+			if ((parser->global.report_id = item_udata(item)) == 0) {
+				hid_debug("report_id 0 is invalid");
+				return -1;
+			}
+			return 0;
+
+		default:
+			hid_debug("unknown global tag 0x%x", item->tag);
+			return -1;
+	}
+}
+
+/*
+ * Process a local item.
+ */
+
+static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
+{
+	__u32 data;
+
+	if (item->size == 0) {
+		hid_debug("item data expected for local item");
+		return -1;
+	}
+
+	data = item_udata(item);
+
+	switch (item->tag) {
+
+		case HID_LOCAL_ITEM_TAG_DELIMITER:
+
+			if (data) {
+				/*
+				 * We treat items before the first delimiter
+				 * as global to all usage sets (branch 0).
+				 * In the moment we process only these global
+				 * items and the first delimiter set.
+				 */
+				if (parser->local.delimiter_depth != 0) {
+					hid_debug("nested delimiters");
+					return -1;
+				}
+				parser->local.delimiter_depth++;
+				parser->local.delimiter_branch++;
+			} else {
+				if (parser->local.delimiter_depth < 1) {
+					hid_debug("bogus close delimiter");
+					return -1;
+				}
+				parser->local.delimiter_depth--;
+			}
+			return 1;
+
+		case HID_LOCAL_ITEM_TAG_USAGE:
+
+			if (parser->local.delimiter_branch < 2) {
+				if (item->size <= 2)
+					data = (parser->global.usage_page << 16) + data;
+				return hid_add_usage(parser, data);
+			}
+			hid_debug("alternative usage ignored");
+			return 0;
+
+		case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM:
+
+			if (parser->local.delimiter_branch < 2) {
+				if (item->size <= 2)
+					data = (parser->global.usage_page << 16) + data;
+				parser->local.usage_minimum = data;
+				return 0;
+			}
+			hid_debug("alternative usage ignored");
+			return 0;
+
+		case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM:
+
+			if (parser->local.delimiter_branch < 2) {
+				unsigned n;
+				if (item->size <= 2)
+					data = (parser->global.usage_page << 16) + data;
+				for (n = parser->local.usage_minimum; n <= data; n++)
+					if (hid_add_usage(parser, n)) {
+						hid_debug("hid_add_usage failed\n");
+						return -1;
+					}
+				return 0;
+			}
+			hid_debug("alternative usage ignored");
+			return 0;
+
+		default:
+
+			hid_debug("unknown local item tag 0x%x", item->tag);
+			return 0;
+	}
+}
+
+/*
+ * Process a main item.
+ */
+
+static int hid_parser_main(struct hid_parser *parser, struct hid_item *item)
+{
+	__u32 data;
+	int ret;
+
+	data = item_udata(item);
+	
+	switch (item->tag) {
+		case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
+			ret = open_collection(parser, data & 3);
+			break;
+		case HID_MAIN_ITEM_TAG_END_COLLECTION:
+			ret = close_collection(parser);
+			break;
+		case HID_MAIN_ITEM_TAG_INPUT:
+			ret = hid_add_field(parser, HID_INPUT_REPORT, data);
+			break;
+		case HID_MAIN_ITEM_TAG_OUTPUT:
+			ret = hid_add_field(parser, HID_OUTPUT_REPORT, data);
+			break;
+		case HID_MAIN_ITEM_TAG_FEATURE:
+			ret = hid_add_field(parser, HID_FEATURE_REPORT, data);
+			break;
+		default:
+			hid_debug("unknown main item tag 0x%x", item->tag);
+			ret = 0;
+	}
+
+	memset(&parser->local, 0, sizeof(parser->local));	/* Reset the local parser environment */
+
+	return ret;
+}
+
+/*
+ * Process a reserved item.
+ */
+
+static int hid_parser_reserved(struct hid_parser *parser, struct hid_item *item)
+{
+	hid_debug("reserved item type, tag 0x%x", item->tag);
+	return 0;
+}
+
+/*
+ * Free a report and all registered fields. The field->usage and
+ * field->value table's are allocated behind the field, so we need
+ * only to free(field) itself.
+ */
+
+static void hid_free_report(struct hid_report *report)
+{
+	unsigned n;
+
+	for (n = 0; n < report->maxfield; n++)
+		kfree(report->field[n]);
+	kfree(report);
+}
+
+/*
+ * Free a device structure, all reports, and all fields.
+ */
+
+static void hid_free_device(struct hid_device *device)
+{
+	unsigned i,j;
+
+	for (i = 0; i < HID_REPORT_TYPES; i++) {
+		struct hid_report_enum *report_enum = device->report_enum + i;
+
+		for (j = 0; j < 256; j++) {
+			struct hid_report *report = report_enum->report_id_hash[j];
+			if (report) hid_free_report(report);
+		}
+	}
+
+	if (device->rdesc) kfree(device->rdesc);
+}
+
+/*
+ * Fetch a report description item from the data stream. We support long
+ * items, though they are not used yet.
+ */
+
+static __u8 *fetch_item(__u8 *start, __u8 *end, struct hid_item *item)
+{
+	if ((end - start) > 0) {
+
+		__u8 b = *start++;
+		item->type = (b >> 2) & 3;
+		item->tag  = (b >> 4) & 15;
+
+		if (item->tag == HID_ITEM_TAG_LONG) {
+
+			item->format = HID_ITEM_FORMAT_LONG;
+
+			if ((end - start) >= 2) {
+
+				item->size = *start++;
+				item->tag  = *start++;
+
+				if ((end - start) >= item->size) {
+					item->data.longdata = start;
+					start += item->size;
+					return start;
+				}
+			}
+		} else {
+
+			item->format = HID_ITEM_FORMAT_SHORT;
+			item->size = b & 3;
+			switch (item->size) {
+
+				case 0:
+					return start;
+
+				case 1: 
+					if ((end - start) >= 1) {
+						item->data.u8 = *start++;
+						return start;
+					}
+					break;
+
+				case 2: 
+					if ((end - start) >= 2) {
+						item->data.u16 = le16_to_cpu( *((__u16*)start)++);
+						return start;
+					}
+
+				case 3: 
+					item->size++;
+					if ((end - start) >= 4) {
+						item->data.u32 = le32_to_cpu( *((__u32*)start)++);
+						return start;
+					}
+			}
+		}
+	}
+	return NULL;
+}
+
+/*
+ * Parse a report description into a hid_device structure. Reports are
+ * enumerated, fields are attached to these reports.
+ */
+
+static struct hid_device *hid_parse_report(__u8 *start, unsigned size)
+{
+	struct hid_device *device;
+	struct hid_parser *parser;
+	struct hid_item    item;
+	__u8 *end;
+	unsigned i;
+	static int (*dispatch_type[])(struct hid_parser *parser,
+				      struct hid_item *item) = {
+		hid_parser_main,
+		hid_parser_global,
+		hid_parser_local,
+		hid_parser_reserved
+	};
+
+	if (!(device = kmalloc(sizeof(struct hid_device), GFP_KERNEL)))
+		return NULL;
+	memset(device, 0, sizeof(struct hid_device));
+
+	for (i = 0; i < HID_REPORT_TYPES; i++)
+		INIT_LIST_HEAD(&device->report_enum[i].report_list);
+
+	if (!(device->rdesc = (__u8 *)kmalloc(size, GFP_KERNEL))) {
+		kfree(device);
+		return NULL;
+	}
+	memcpy(device->rdesc, start, size);
+
+	if (!(parser = kmalloc(sizeof(struct hid_parser), GFP_KERNEL))) {
+		kfree(device->rdesc);
+		kfree(device);
+		return NULL;
+	}
+	memset(parser, 0, sizeof(struct hid_parser));
+	parser->device = device;
+	
+	end = start + size;
+	while ((start = fetch_item(start, end, &item)) != 0) {
+		if (item.format != HID_ITEM_FORMAT_SHORT) {
+			hid_debug("unexpected long global item");
+			hid_free_device(device);
+			kfree(parser);
+			return NULL;
+		}
+		if (dispatch_type[item.type](parser, &item)) {
+			hid_debug("item %u %u %u %u parsing failed\n",
+				item.format, (unsigned)item.size, (unsigned)item.type, (unsigned)item.tag);
+			hid_free_device(device);
+			kfree(parser);
+			return NULL;
+		}
+
+		if (start == end) {
+			if (parser->collection_stack_ptr) {
+				hid_debug("unbalanced collection at end of report description");
+				hid_free_device(device);
+				kfree(parser);
+				return NULL;
+			}
+			if (parser->local.delimiter_depth) {
+				hid_debug("unbalanced delimiter at end of report description");
+				hid_free_device(device);
+				kfree(parser);
+				return NULL;
+			}
+			kfree(parser);
+			return device;
+		}
+	}
+
+	hid_debug("item fetching failed at offset %d\n", (int)(end - start));
+	hid_free_device(device);
+	kfree(parser);
+	return NULL;
+}
+
+/*
+ * Convert a signed n-bit integer to signed 32-bit integer. Common
+ * cases are done through the compiler, the screwed things has to be
+ * done by hand.
+ */
+
+static __inline__ __s32 snto32(__u32 value, unsigned n)
+{
+	switch (n) {
+		case 8:  return ((__s8)value);
+		case 16: return ((__s16)value);
+		case 32: return ((__s32)value);
+	}
+	return value & (1 << (n - 1)) ? value | (-1 << n) : value;
+}
+
+/*
+ * Convert a signed 32-bit integer to a signed n-bit integer. 
+ */
+
+static __inline__ __u32 s32ton(__s32 value, unsigned n)
+{
+	__s32 a = value >> (n - 1);
+	if (a && a != -1) return value > 0 ? 1 << (n - 1) : (1 << n) - 1;
+	return value & ((1 << n) - 1);
+}
+
+/*
+ * Extract/implement a data field from/to a report. We use 64-bit unsigned,
+ * 32-bit aligned, so that we can possibly have alignment problems on some
+ * odd architectures.
+ */
+
+static __inline__ __u32 extract(__u8 *report, unsigned offset, unsigned n)
+{
+	report += (offset >> 5) << 2; offset &= 31;
+	return (le64_to_cpu(*(__u64*)report) >> offset) & ((1 << n) - 1);
+}
+
+static __inline__ void implement(__u8 *report, unsigned offset, unsigned n, __u32 value)
+{
+	report += (offset >> 5) << 2; offset &= 31;
+	*(__u64*)report &= cpu_to_le64(~((1ULL << n) - 1) << offset);
+	*(__u64*)report |= cpu_to_le64((__u64)value << offset);
+}
+
+static void hid_configure_usage(struct hid_device *device, struct hid_field *field, struct hid_usage *usage)
+{
+	struct input_dev *input = &device->input;
+	int max;
+	unsigned long *bit;
+
+	switch (usage->hid & HID_USAGE_PAGE) {
+
+		case HID_UP_KEYBOARD:
+
+			if ((usage->hid & HID_USAGE) < 256) {
+				if (!(usage->code = hid_keyboard[usage->hid & HID_USAGE]))
+					return;
+			} else
+				usage->code = KEY_UNKNOWN;
+
+			set_bit(EV_REP, input->evbit);
+			usage->type = EV_KEY; bit = input->keybit; max = KEY_MAX;
+			break; 
+
+		case HID_UP_BUTTON:
+
+			usage->code = ((usage->hid - 1) & 0xf) + 0x100;
+			usage->type = EV_KEY; bit = input->keybit; max = KEY_MAX;
+			
+			switch (device->application) {
+				case HID_GD_GAMEPAD:  usage->code += 0x10;
+				case HID_GD_JOYSTICK: usage->code += 0x10;
+				case HID_GD_MOUSE:    usage->code += 0x10;
+			}
+			break;
+
+		case HID_UP_GENDESK:
+
+			usage->code = usage->hid & 0xf;
+
+			if (field->flags & HID_MAIN_ITEM_RELATIVE) {
+				usage->type = EV_REL; bit = input->relbit; max = REL_MAX;
+				break;
+			} 
+
+			usage->type = EV_ABS; bit = input->absbit; max = ABS_MAX;
+
+			if (usage->hid == HID_GD_HATSWITCH) {
+				usage->code = ABS_HAT0X;
+				usage->hat = 1 + (field->logical_maximum == 4);
+			}
+			break;
+
+		default:
+
+			if (field->flags & HID_MAIN_ITEM_RELATIVE) {
+				usage->code = REL_MISC;
+				usage->type = EV_REL; bit = input->relbit; max = REL_MAX;
+				break;
+			}
+
+			if (field->logical_minimum == 0 && field->logical_maximum == 1) {
+				usage->code = BTN_MISC;
+				usage->type = EV_KEY; bit = input->keybit; max = KEY_MAX;
+				break;
+			}
+
+			usage->code = ABS_MISC;
+			usage->type = EV_ABS; bit = input->absbit; max = ABS_MAX;
+			break;
+	}
+
+	set_bit(usage->type, input->evbit);
+
+	while (usage->code <= max && test_and_set_bit(usage->code, bit)) {
+		usage->code = find_next_zero_bit(bit, max + 1, usage->code);
+	}
+
+	if (usage->type == EV_ABS) {
+		int a = field->logical_minimum;
+		int b = field->logical_maximum;
+
+		input->absmin[usage->code] = a; 
+		input->absmax[usage->code] = b;
+		input->absfuzz[usage->code] = (b - a) >> 8;
+		input->absflat[usage->code] = (b - a) >> 4;
+	}
+
+	if (usage->hat) {
+		int i;
+		for (i = usage->code; i < usage->code + 2; i++) {
+			input->absmax[i] = 1;
+			input->absmin[i] = -1;
+			input->absfuzz[i] = 0;
+			input->absflat[i] = 0;
+		}
+		set_bit(usage->code + 1, input->absbit);
+	}
+}
+
+static void hid_process_event(struct input_dev *input, struct hid_usage *usage, __s32 value)
+{
+	hid_dump_input(usage, value);
+
+	if (usage->hat) {
+		if (usage->hat == 2) value = value * 2 - 1;
+		input_event(input, usage->type, usage->code    , hid_hat_to_axis[value].x);
+		input_event(input, usage->type, usage->code + 1, hid_hat_to_axis[value].y);
+		return;
+	}
+
+	input_event(input, usage->type, usage->code, value);
+}
+
+/*
+ * Search an array for a value.
+ */
+
+static __inline__ int search(__s32 *array, __s32 value, unsigned n)
+{
+	while (n--) if (*array++ == value) return 0;
+	return -1;
+}
+
+/*
+ * Analyse a received field, and fetch the data from it. The field
+ * content is stored for next report processing (we do differential
+ * reporting to the layer).
+ */
+
+static void hid_input_field(struct hid_device *dev, struct hid_field *field, __u8 *data)
+{
+	unsigned n;
+	unsigned count = field->report_count;
+	unsigned offset = field->report_offset;
+	unsigned size = field->report_size;
+	__s32 min = field->logical_minimum;
+	__s32 max = field->logical_maximum;
+	__s32 value[count]; /* WARNING: gcc specific */
+   
+	for (n = 0; n < count; n++)
+			value[n] = min < 0 ? snto32(extract(data, offset + n * size, size), size) : 
+						    extract(data, offset + n * size, size);
+
+	for (n = 0; n < count; n++) {
+
+		if (HID_MAIN_ITEM_VARIABLE & field->flags) {
+
+			if (field->flags & HID_MAIN_ITEM_RELATIVE) {
+				if (!value[n]) continue;
+			} else {
+				if (value[n] == field->value[n]) continue;
+			}
+			hid_process_event(&dev->input, &field->usage[n], value[n]);
+
+		} else {
+
+			if (field->value[n] >= min && field->value[n] <= max			/* non-NULL value */
+				&& field->usage[field->value[n] - min].hid			/* nonzero usage */
+				&& search(value, field->value[n], count))
+					hid_process_event(&dev->input, &field->usage[field->value[n] - min], 0);
+
+			if (value[n] >= min && value[n] <= max					/* non-NULL value */
+				&& field->usage[value[n] - min].hid				/* nonzero usage */
+				&& search(field->value, value[n], count))
+					hid_process_event(&dev->input, &field->usage[value[n] - min], 1);
+		}
+	}
+
+	memcpy(field->value, value, count * sizeof(__s32));
+}
+
+/*
+ * Interrupt input handler - analyse a received report.
+ */
+
+static void hid_irq(struct urb *urb)
+{
+	struct hid_device *device = urb->context;
+	struct hid_report_enum *report_enum = device->report_enum + HID_INPUT_REPORT;
+	struct hid_report *report;
+	__u8 *data = urb->transfer_buffer;
+	int len = urb->actual_length;
+	int n;
+
+	if (urb->status) {
+		hid_debug("nonzero status in irq %d", urb->status);
+		return;
+	}
+
+	if (!len) {
+		hid_debug("empty report");
+		return;
+	}
+
+#ifdef CONFIG_USB_HID_DEBUG_LOTS
+	printk(KERN_DEBUG "hid: report (size %u) (%snumbered) = ", len, report_enum->numbered ? "" : "un");
+	for (n = 0; n < len; n++)
+		printk(" %02x", data[n]);
+	printk("\n");
+#endif
+
+	n = 0;				/* Normally report number is 0 */
+
+	if (report_enum->numbered) {	/* Device uses numbered reports, data[0] is report number */
+		n = *data++;
+		len--;
+	} 
+
+	if (!(report = report_enum->report_id_hash[n])) {
+		hid_debug("undefined report_id %d received", n);
+#ifdef CONFIG_USB_HID_DEBUG
+			printk(KERN_DEBUG "hid: report (size %u) = ", len);
+			for (n = 0; n < len; n++)
+				printk(" %02x", data[n]);
+			printk("\n");
+#endif
+	
+		return;
+	}
+
+	if (len < ((report->size - 1) >> 3) + 1) {
+		hid_debug("report %d is too short, (%d < %d)", report->id, len, ((report->size - 1) >> 3) + 1);
+		return;
+	}
+
+	for (n = 0; n < report->maxfield; n++)
+		hid_input_field(device, report->field[n], data);
+
+	return;
+}
+
+/*
+ * Configure the input layer interface
+ * Read all reports and initalize the absoulte field values.
+ */
+
+static void hid_init_input(struct hid_device *hid)
+{
+	struct hid_report_enum *report_enum = hid->report_enum + HID_INPUT_REPORT;
+	struct list_head *list;
+	int i, j;
+
+	list = report_enum->report_list.next;
+
+	while (list != &report_enum->report_list) {
+
+		struct hid_report *report = (struct hid_report *) list;
+		int rlen = ((report->size - 1) >> 3) + 1 + report_enum->numbered;
+		int read;
+
+		list = list->next;
+
+		for (i = 0; i < report->maxfield; i++)
+			for (j = 0; j < report->field[i]->maxusage; j++)
+				hid_configure_usage(hid, report->field[i], report->field[i]->usage + j);
+
+#if 1
+		{
+			char rdata[rlen];
+			struct urb urb;
+
+			memset(&urb, 0, sizeof(struct urb));
+			memset(rdata, 0, rlen);
+
+			urb.transfer_buffer = rdata;
+			urb.actual_length = rlen;
+			urb.context = hid;
+
+			hid_debug("getting report type %d id %d len %d", report->type + 1, report->id, rlen);
+
+			if ((read = usb_get_report(hid->dev, report->type + 1, report->id, hid->ifnum, rdata, rlen)) != rlen) {
+				hid_debug("reading report failed rlen %d read %d", rlen, read);
+#ifdef CONFIG_USB_HID_DEBUG
+				printk(KERN_DEBUG "hid: report = ");
+				for (j = 0; j < rlen; j++) printk(" %02x", rdata[j]);
+				printk("\n");
+#endif
+				continue;
+			}
+
+			hid_irq(&urb);
+		}
+#endif
+	}
+}
+
+/*
+ * Output the field into the report.
+ */
+
+static void hid_output_field(struct hid_field *field, __u8 *data)
+{
+	unsigned count = field->report_count;
+	unsigned offset = field->report_offset;
+	unsigned size = field->report_size;
+	unsigned n;
+   
+	for (n = 0; n < count; n++) {
+		if (field->logical_minimum < 0)	/* signed values */
+			implement(data, offset + n * size, size, s32ton(field->value[n], size));
+		 else				/* unsigned values */
+			implement(data, offset + n * size, size, field->value[n]);
+       	}
+}
+
+/*
+ * Create a report.
+ */
+
+void hid_output_report(struct hid_report *report, __u8 *data)
+{
+	unsigned n;
+
+	/* skip the ID if we have a single report */
+	if (report->device->report_enum[report->type].numbered)
+		*data++ = report->id;
+
+	for (n = 0; n < report->maxfield; n++)
+		hid_output_field(report->field[n], data);
+};
+
+/*
+ * Set a field value. The report this field belongs to has to be
+ * created and transfered to the device, to set this value in the
+ * device.
+ */
+
+int hid_set_field(struct hid_field *field, unsigned offset, __s32 value)
+{
+	unsigned size = field->report_size;
+	
+	if (offset >= field->report_count) {
+		hid_debug("offset exceeds report_count");
+		return -1;
+	}
+	if (field->logical_minimum < 0) {
+		if (value != snto32(s32ton(value, size), size)) {
+			hid_debug("value %d is out of range", value);
+			return -1;
+		}
+	}
+	if (   (value > field->logical_maximum)
+	    || (value < field->logical_minimum)) {
+		hid_debug("value %d is invalid", value);
+		return -1;
+	}
+	field->value[offset] = value;
+	return 0;
+}
+
+static struct hid_device *usb_hid_configure(struct usb_device *dev, int ifnum)
+{
+	struct usb_interface_descriptor *interface = &dev->actconfig->interface[ifnum].altsetting[0];
+	struct usb_hid_descriptor *hdesc;
+	struct hid_device *hid;
+	unsigned rsize = 0;
+	int n;
+
+	if (interface->bInterfaceClass != USB_INTERFACE_CLASS_HID)
+		return NULL;
+
+	if (usb_get_extra_descriptor(interface, USB_DT_HID, &hdesc)
+		&& usb_get_extra_descriptor(&interface->endpoint[0], USB_DT_HID, &hdesc)) {
+			hid_debug("class descriptor not present\n");
+			return NULL;
+	}
+
+	for (n = 0; n < hdesc->bNumDescriptors; n++)
+		if (hdesc->desc[n].bDescriptorType == USB_DT_REPORT)
+			rsize = le16_to_cpu(hdesc->desc[n].wDescriptorLength);
+
+	if (!rsize || rsize > 1024) {
+		hid_debug("weird size of report descriptor (%u)", rsize);
+		return NULL;
+	}
+
+	{
+		__u8 rdesc[rsize];
+
+		if ((n = usb_get_class_descriptor(dev, USB_DT_REPORT, 0, ifnum, rdesc, rsize)) < 0) {
+			hid_debug("reading report descriptor failed");
+			return NULL;
+		}
+
+#ifdef CONFIG_USB_HID_DEBUG
+		printk(KERN_DEBUG "hid: report (size %u, read %d) = ", rsize, n);
+		for (n = 0; n < rsize; n++)
+			printk(" %02x", (unsigned) rdesc[n]);
+		printk("\n");
+#endif
+
+		if (!(hid = hid_parse_report(rdesc, rsize))) {
+			hid_debug("parsing report descriptor failed");
+			return NULL;
+		}
+	}
+
+	for (n = 0; n < interface->bNumEndpoints; n++) {
+
+		struct usb_endpoint_descriptor *endpoint = &interface->endpoint[n];
+		int pipe, maxp;
+
+		if ((endpoint->bmAttributes & 3) != 3)		/* Not an interrupt endpoint */
+			continue;
+
+		if (!(endpoint->bEndpointAddress & 0x80)) 	/* Not an input endpoint */
+			continue;
+
+		pipe = usb_rcvintpipe(dev, endpoint->bEndpointAddress);
+		maxp = usb_maxpacket(dev, pipe, usb_pipeout(pipe));
+
+		FILL_INT_URB(&hid->urb, dev, pipe, hid->buffer, maxp > 32 ? 32 : maxp, hid_irq, hid, endpoint->bInterval);
+	
+		if (usb_submit_urb(&hid->urb)) {
+			hid_debug("submitting interrupt URB failed");
+			continue;
+		}
+
+		break;
+	}
+
+	if (n == interface->bNumEndpoints) {
+		hid_debug("couldn't find an input interrupt endpoint");
+		hid_free_device(hid);
+		return NULL;
+	}
+
+	hid->version = hdesc->bcdHID;
+	hid->country = hdesc->bCountryCode;
+	hid->dev = dev;
+	hid->ifnum = ifnum;
+
+	return hid;
+}
+
+static void* hid_probe(struct usb_device *dev, unsigned int ifnum)
+{
+	char *hid_name[] = {"Device", "Pointer", "Mouse", "Device", "Joystick",
+				"Gamepad", "Keyboard", "Keypad", "Multi-Axis Controller"};
+	struct hid_device *hid;
+
+	hid_debug("HID probe called for ifnum %d", ifnum);
+
+	if (!(hid = usb_hid_configure(dev, ifnum)))
+		return NULL;
+
+	hid_dump_device(hid);
+
+	hid_init_input(hid);
+	input_register_device(&hid->input);
+
+	printk(KERN_INFO "input%d: USB HID v%d.%d %s\n",
+		hid->input.number, hid->version >> 8, hid->version & 0xff,
+		(hid->application & 0xffff) <= 8 ? hid_name[hid->application & 0xffff] : "device");
+
+	return hid;
+}
+
+static void hid_disconnect(struct usb_device *dev, void *ptr)
+{
+	struct hid_device *hid = ptr;
+
+	hid_debug("cleanup called");
+	usb_unlink_urb(&hid->urb);
+	input_unregister_device(&hid->input);
+	hid_free_device(hid);
+}
+
+static struct usb_driver hid_driver = {
+	name:		"hid",
+	probe:		hid_probe,
+	disconnect:	hid_disconnect
+};
+
+#ifdef MODULE
+void cleanup_module(void)
+{
+	usb_deregister(&hid_driver);
+}
+
+int init_module(void)
+#else
+int hid_init(void)
+#endif
+{
+	usb_register(&hid_driver);
+	return 0;
+}

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)