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993 lines
24 KiB
993 lines
24 KiB
/*
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* HID support for Linux
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*
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* Copyright (c) 1999 Andreas Gal
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* Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
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* Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
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* Copyright (c) 2006-2007 Jiri Kosina
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*/
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/*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the Free
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* Software Foundation; either version 2 of the License, or (at your option)
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* any later version.
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*/
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/list.h>
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#include <linux/mm.h>
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#include <linux/spinlock.h>
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#include <asm/unaligned.h>
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#include <asm/byteorder.h>
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#include <linux/input.h>
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#include <linux/wait.h>
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#include <linux/vmalloc.h>
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#include <linux/hid.h>
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#include <linux/hiddev.h>
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#include <linux/hid-debug.h>
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/*
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* Version Information
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*/
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#define DRIVER_VERSION "v2.6"
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#define DRIVER_AUTHOR "Andreas Gal, Vojtech Pavlik, Jiri Kosina"
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#define DRIVER_DESC "HID core driver"
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#define DRIVER_LICENSE "GPL"
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/*
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* Register a new report for a device.
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*/
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static struct hid_report *hid_register_report(struct hid_device *device, unsigned type, unsigned id)
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{
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struct hid_report_enum *report_enum = device->report_enum + type;
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struct hid_report *report;
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if (report_enum->report_id_hash[id])
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return report_enum->report_id_hash[id];
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if (!(report = kzalloc(sizeof(struct hid_report), GFP_KERNEL)))
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return NULL;
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if (id != 0)
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report_enum->numbered = 1;
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report->id = id;
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report->type = type;
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report->size = 0;
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report->device = device;
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report_enum->report_id_hash[id] = report;
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list_add_tail(&report->list, &report_enum->report_list);
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return report;
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}
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/*
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* Register a new field for this report.
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*/
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static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages, unsigned values)
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{
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struct hid_field *field;
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if (report->maxfield == HID_MAX_FIELDS) {
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dbg("too many fields in report");
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return NULL;
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}
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if (!(field = kzalloc(sizeof(struct hid_field) + usages * sizeof(struct hid_usage)
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+ values * sizeof(unsigned), GFP_KERNEL))) return NULL;
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field->index = report->maxfield++;
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report->field[field->index] = field;
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field->usage = (struct hid_usage *)(field + 1);
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field->value = (unsigned *)(field->usage + usages);
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field->report = report;
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return field;
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}
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/*
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* Open a collection. The type/usage is pushed on the stack.
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*/
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static int open_collection(struct hid_parser *parser, unsigned type)
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{
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struct hid_collection *collection;
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unsigned usage;
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usage = parser->local.usage[0];
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if (parser->collection_stack_ptr == HID_COLLECTION_STACK_SIZE) {
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dbg("collection stack overflow");
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return -1;
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}
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if (parser->device->maxcollection == parser->device->collection_size) {
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collection = kmalloc(sizeof(struct hid_collection) *
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parser->device->collection_size * 2, GFP_KERNEL);
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if (collection == NULL) {
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dbg("failed to reallocate collection array");
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return -1;
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}
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memcpy(collection, parser->device->collection,
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sizeof(struct hid_collection) *
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parser->device->collection_size);
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memset(collection + parser->device->collection_size, 0,
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sizeof(struct hid_collection) *
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parser->device->collection_size);
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kfree(parser->device->collection);
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parser->device->collection = collection;
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parser->device->collection_size *= 2;
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}
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parser->collection_stack[parser->collection_stack_ptr++] =
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parser->device->maxcollection;
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collection = parser->device->collection +
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parser->device->maxcollection++;
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collection->type = type;
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collection->usage = usage;
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collection->level = parser->collection_stack_ptr - 1;
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if (type == HID_COLLECTION_APPLICATION)
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parser->device->maxapplication++;
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return 0;
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}
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/*
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* Close a collection.
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*/
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static int close_collection(struct hid_parser *parser)
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{
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if (!parser->collection_stack_ptr) {
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dbg("collection stack underflow");
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return -1;
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}
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parser->collection_stack_ptr--;
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return 0;
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}
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/*
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* Climb up the stack, search for the specified collection type
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* and return the usage.
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*/
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static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type)
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{
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int n;
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for (n = parser->collection_stack_ptr - 1; n >= 0; n--)
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if (parser->device->collection[parser->collection_stack[n]].type == type)
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return parser->device->collection[parser->collection_stack[n]].usage;
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return 0; /* we know nothing about this usage type */
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}
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/*
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* Add a usage to the temporary parser table.
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*/
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static int hid_add_usage(struct hid_parser *parser, unsigned usage)
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{
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if (parser->local.usage_index >= HID_MAX_USAGES) {
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dbg("usage index exceeded");
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return -1;
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}
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parser->local.usage[parser->local.usage_index] = usage;
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parser->local.collection_index[parser->local.usage_index] =
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parser->collection_stack_ptr ?
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parser->collection_stack[parser->collection_stack_ptr - 1] : 0;
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parser->local.usage_index++;
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return 0;
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}
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/*
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* Register a new field for this report.
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*/
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static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsigned flags)
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{
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struct hid_report *report;
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struct hid_field *field;
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int usages;
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unsigned offset;
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int i;
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if (!(report = hid_register_report(parser->device, report_type, parser->global.report_id))) {
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dbg("hid_register_report failed");
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return -1;
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}
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if (parser->global.logical_maximum < parser->global.logical_minimum) {
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dbg("logical range invalid %d %d", parser->global.logical_minimum, parser->global.logical_maximum);
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return -1;
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}
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offset = report->size;
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report->size += parser->global.report_size * parser->global.report_count;
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if (!parser->local.usage_index) /* Ignore padding fields */
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return 0;
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usages = max_t(int, parser->local.usage_index, parser->global.report_count);
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if ((field = hid_register_field(report, usages, parser->global.report_count)) == NULL)
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return 0;
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field->physical = hid_lookup_collection(parser, HID_COLLECTION_PHYSICAL);
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field->logical = hid_lookup_collection(parser, HID_COLLECTION_LOGICAL);
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field->application = hid_lookup_collection(parser, HID_COLLECTION_APPLICATION);
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for (i = 0; i < usages; i++) {
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int j = i;
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/* Duplicate the last usage we parsed if we have excess values */
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if (i >= parser->local.usage_index)
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j = parser->local.usage_index - 1;
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field->usage[i].hid = parser->local.usage[j];
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field->usage[i].collection_index =
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parser->local.collection_index[j];
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}
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field->maxusage = usages;
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field->flags = flags;
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field->report_offset = offset;
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field->report_type = report_type;
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field->report_size = parser->global.report_size;
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field->report_count = parser->global.report_count;
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field->logical_minimum = parser->global.logical_minimum;
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field->logical_maximum = parser->global.logical_maximum;
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field->physical_minimum = parser->global.physical_minimum;
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field->physical_maximum = parser->global.physical_maximum;
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field->unit_exponent = parser->global.unit_exponent;
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field->unit = parser->global.unit;
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return 0;
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}
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/*
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* Read data value from item.
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*/
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static u32 item_udata(struct hid_item *item)
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{
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switch (item->size) {
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case 1: return item->data.u8;
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case 2: return item->data.u16;
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case 4: return item->data.u32;
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}
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return 0;
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}
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static s32 item_sdata(struct hid_item *item)
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{
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switch (item->size) {
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case 1: return item->data.s8;
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case 2: return item->data.s16;
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case 4: return item->data.s32;
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}
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return 0;
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}
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/*
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* Process a global item.
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*/
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static int hid_parser_global(struct hid_parser *parser, struct hid_item *item)
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{
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switch (item->tag) {
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case HID_GLOBAL_ITEM_TAG_PUSH:
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if (parser->global_stack_ptr == HID_GLOBAL_STACK_SIZE) {
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dbg("global enviroment stack overflow");
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return -1;
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}
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memcpy(parser->global_stack + parser->global_stack_ptr++,
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&parser->global, sizeof(struct hid_global));
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return 0;
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case HID_GLOBAL_ITEM_TAG_POP:
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if (!parser->global_stack_ptr) {
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dbg("global enviroment stack underflow");
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return -1;
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}
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memcpy(&parser->global, parser->global_stack + --parser->global_stack_ptr,
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sizeof(struct hid_global));
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return 0;
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case HID_GLOBAL_ITEM_TAG_USAGE_PAGE:
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parser->global.usage_page = item_udata(item);
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return 0;
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case HID_GLOBAL_ITEM_TAG_LOGICAL_MINIMUM:
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parser->global.logical_minimum = item_sdata(item);
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return 0;
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case HID_GLOBAL_ITEM_TAG_LOGICAL_MAXIMUM:
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if (parser->global.logical_minimum < 0)
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parser->global.logical_maximum = item_sdata(item);
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else
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parser->global.logical_maximum = item_udata(item);
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return 0;
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case HID_GLOBAL_ITEM_TAG_PHYSICAL_MINIMUM:
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parser->global.physical_minimum = item_sdata(item);
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return 0;
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case HID_GLOBAL_ITEM_TAG_PHYSICAL_MAXIMUM:
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if (parser->global.physical_minimum < 0)
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parser->global.physical_maximum = item_sdata(item);
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else
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parser->global.physical_maximum = item_udata(item);
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return 0;
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case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT:
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parser->global.unit_exponent = item_sdata(item);
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return 0;
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case HID_GLOBAL_ITEM_TAG_UNIT:
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parser->global.unit = item_udata(item);
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return 0;
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case HID_GLOBAL_ITEM_TAG_REPORT_SIZE:
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if ((parser->global.report_size = item_udata(item)) > 32) {
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dbg("invalid report_size %d", parser->global.report_size);
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return -1;
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}
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return 0;
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case HID_GLOBAL_ITEM_TAG_REPORT_COUNT:
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if ((parser->global.report_count = item_udata(item)) > HID_MAX_USAGES) {
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dbg("invalid report_count %d", parser->global.report_count);
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return -1;
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}
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return 0;
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case HID_GLOBAL_ITEM_TAG_REPORT_ID:
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if ((parser->global.report_id = item_udata(item)) == 0) {
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dbg("report_id 0 is invalid");
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return -1;
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}
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return 0;
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default:
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dbg("unknown global tag 0x%x", item->tag);
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return -1;
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}
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}
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/*
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* Process a local item.
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*/
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static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
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{
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__u32 data;
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unsigned n;
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if (item->size == 0) {
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dbg("item data expected for local item");
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return -1;
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}
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data = item_udata(item);
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switch (item->tag) {
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case HID_LOCAL_ITEM_TAG_DELIMITER:
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if (data) {
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/*
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* We treat items before the first delimiter
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* as global to all usage sets (branch 0).
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* In the moment we process only these global
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* items and the first delimiter set.
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*/
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if (parser->local.delimiter_depth != 0) {
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dbg("nested delimiters");
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return -1;
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}
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parser->local.delimiter_depth++;
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parser->local.delimiter_branch++;
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} else {
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if (parser->local.delimiter_depth < 1) {
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dbg("bogus close delimiter");
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return -1;
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}
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parser->local.delimiter_depth--;
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}
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return 1;
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case HID_LOCAL_ITEM_TAG_USAGE:
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if (parser->local.delimiter_branch > 1) {
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dbg("alternative usage ignored");
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return 0;
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}
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if (item->size <= 2)
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data = (parser->global.usage_page << 16) + data;
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return hid_add_usage(parser, data);
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case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM:
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if (parser->local.delimiter_branch > 1) {
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dbg("alternative usage ignored");
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return 0;
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}
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if (item->size <= 2)
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data = (parser->global.usage_page << 16) + data;
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parser->local.usage_minimum = data;
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return 0;
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case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM:
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if (parser->local.delimiter_branch > 1) {
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dbg("alternative usage ignored");
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return 0;
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}
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if (item->size <= 2)
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data = (parser->global.usage_page << 16) + data;
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for (n = parser->local.usage_minimum; n <= data; n++)
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if (hid_add_usage(parser, n)) {
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dbg("hid_add_usage failed\n");
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return -1;
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}
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return 0;
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default:
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dbg("unknown local item tag 0x%x", item->tag);
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return 0;
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}
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return 0;
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}
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/*
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* Process a main item.
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*/
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static int hid_parser_main(struct hid_parser *parser, struct hid_item *item)
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{
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__u32 data;
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int ret;
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data = item_udata(item);
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switch (item->tag) {
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case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
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ret = open_collection(parser, data & 0xff);
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break;
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case HID_MAIN_ITEM_TAG_END_COLLECTION:
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ret = close_collection(parser);
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break;
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case HID_MAIN_ITEM_TAG_INPUT:
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ret = hid_add_field(parser, HID_INPUT_REPORT, data);
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break;
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case HID_MAIN_ITEM_TAG_OUTPUT:
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ret = hid_add_field(parser, HID_OUTPUT_REPORT, data);
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break;
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case HID_MAIN_ITEM_TAG_FEATURE:
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ret = hid_add_field(parser, HID_FEATURE_REPORT, data);
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break;
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default:
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dbg("unknown main item tag 0x%x", item->tag);
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ret = 0;
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}
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memset(&parser->local, 0, sizeof(parser->local)); /* Reset the local parser environment */
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return ret;
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}
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/*
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* Process a reserved item.
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*/
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static int hid_parser_reserved(struct hid_parser *parser, struct hid_item *item)
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{
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dbg("reserved item type, tag 0x%x", item->tag);
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return 0;
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}
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/*
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* Free a report and all registered fields. The field->usage and
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* field->value table's are allocated behind the field, so we need
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* only to free(field) itself.
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*/
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static void hid_free_report(struct hid_report *report)
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{
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unsigned n;
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for (n = 0; n < report->maxfield; n++)
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kfree(report->field[n]);
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kfree(report);
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}
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/*
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* Free a device structure, all reports, and all fields.
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*/
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void hid_free_device(struct hid_device *device)
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{
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unsigned i,j;
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for (i = 0; i < HID_REPORT_TYPES; i++) {
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struct hid_report_enum *report_enum = device->report_enum + i;
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for (j = 0; j < 256; j++) {
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struct hid_report *report = report_enum->report_id_hash[j];
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if (report)
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hid_free_report(report);
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}
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}
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kfree(device->rdesc);
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kfree(device->collection);
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kfree(device);
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}
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EXPORT_SYMBOL_GPL(hid_free_device);
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/*
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* Fetch a report description item from the data stream. We support long
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* items, though they are not used yet.
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*/
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static u8 *fetch_item(__u8 *start, __u8 *end, struct hid_item *item)
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{
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u8 b;
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if ((end - start) <= 0)
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|
return NULL;
|
|
|
|
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)
|
|
return NULL;
|
|
|
|
item->size = *start++;
|
|
item->tag = *start++;
|
|
|
|
if ((end - start) < item->size)
|
|
return NULL;
|
|
|
|
item->data.longdata = start;
|
|
start += item->size;
|
|
return start;
|
|
}
|
|
|
|
item->format = HID_ITEM_FORMAT_SHORT;
|
|
item->size = b & 3;
|
|
|
|
switch (item->size) {
|
|
|
|
case 0:
|
|
return start;
|
|
|
|
case 1:
|
|
if ((end - start) < 1)
|
|
return NULL;
|
|
item->data.u8 = *start++;
|
|
return start;
|
|
|
|
case 2:
|
|
if ((end - start) < 2)
|
|
return NULL;
|
|
item->data.u16 = le16_to_cpu(get_unaligned((__le16*)start));
|
|
start = (__u8 *)((__le16 *)start + 1);
|
|
return start;
|
|
|
|
case 3:
|
|
item->size++;
|
|
if ((end - start) < 4)
|
|
return NULL;
|
|
item->data.u32 = le32_to_cpu(get_unaligned((__le32*)start));
|
|
start = (__u8 *)((__le32 *)start + 1);
|
|
return start;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Parse a report description into a hid_device structure. Reports are
|
|
* enumerated, fields are attached to these reports.
|
|
*/
|
|
|
|
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 = kzalloc(sizeof(struct hid_device), GFP_KERNEL)))
|
|
return NULL;
|
|
|
|
if (!(device->collection = kzalloc(sizeof(struct hid_collection) *
|
|
HID_DEFAULT_NUM_COLLECTIONS, GFP_KERNEL))) {
|
|
kfree(device);
|
|
return NULL;
|
|
}
|
|
device->collection_size = HID_DEFAULT_NUM_COLLECTIONS;
|
|
|
|
for (i = 0; i < HID_REPORT_TYPES; i++)
|
|
INIT_LIST_HEAD(&device->report_enum[i].report_list);
|
|
|
|
if (!(device->rdesc = kmalloc(size, GFP_KERNEL))) {
|
|
kfree(device->collection);
|
|
kfree(device);
|
|
return NULL;
|
|
}
|
|
memcpy(device->rdesc, start, size);
|
|
device->rsize = size;
|
|
|
|
if (!(parser = vmalloc(sizeof(struct hid_parser)))) {
|
|
kfree(device->rdesc);
|
|
kfree(device->collection);
|
|
kfree(device);
|
|
return NULL;
|
|
}
|
|
memset(parser, 0, sizeof(struct hid_parser));
|
|
parser->device = device;
|
|
|
|
end = start + size;
|
|
while ((start = fetch_item(start, end, &item)) != NULL) {
|
|
|
|
if (item.format != HID_ITEM_FORMAT_SHORT) {
|
|
dbg("unexpected long global item");
|
|
hid_free_device(device);
|
|
vfree(parser);
|
|
return NULL;
|
|
}
|
|
|
|
if (dispatch_type[item.type](parser, &item)) {
|
|
dbg("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);
|
|
return NULL;
|
|
}
|
|
|
|
if (start == end) {
|
|
if (parser->collection_stack_ptr) {
|
|
dbg("unbalanced collection at end of report description");
|
|
hid_free_device(device);
|
|
vfree(parser);
|
|
return NULL;
|
|
}
|
|
if (parser->local.delimiter_depth) {
|
|
dbg("unbalanced delimiter at end of report description");
|
|
hid_free_device(device);
|
|
vfree(parser);
|
|
return NULL;
|
|
}
|
|
vfree(parser);
|
|
return device;
|
|
}
|
|
}
|
|
|
|
dbg("item fetching failed at offset %d\n", (int)(end - start));
|
|
hid_free_device(device);
|
|
vfree(parser);
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL_GPL(hid_parse_report);
|
|
|
|
/*
|
|
* 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 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 u32 s32ton(__s32 value, unsigned n)
|
|
{
|
|
s32 a = value >> (n - 1);
|
|
if (a && a != -1)
|
|
return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1;
|
|
return value & ((1 << n) - 1);
|
|
}
|
|
|
|
/*
|
|
* Extract/implement a data field from/to a little endian report (bit array).
|
|
*
|
|
* Code sort-of follows HID spec:
|
|
* http://www.usb.org/developers/devclass_docs/HID1_11.pdf
|
|
*
|
|
* While the USB HID spec allows unlimited length bit fields in "report
|
|
* descriptors", most devices never use more than 16 bits.
|
|
* One model of UPS is claimed to report "LINEV" as a 32-bit field.
|
|
* Search linux-kernel and linux-usb-devel archives for "hid-core extract".
|
|
*/
|
|
|
|
static __inline__ __u32 extract(__u8 *report, unsigned offset, unsigned n)
|
|
{
|
|
u64 x;
|
|
|
|
WARN_ON(n > 32);
|
|
|
|
report += offset >> 3; /* adjust byte index */
|
|
offset &= 7; /* now only need bit offset into one byte */
|
|
x = le64_to_cpu(get_unaligned((__le64 *) report));
|
|
x = (x >> offset) & ((1ULL << n) - 1); /* extract bit field */
|
|
return (u32) x;
|
|
}
|
|
|
|
/*
|
|
* "implement" : set bits in a little endian bit stream.
|
|
* Same concepts as "extract" (see comments above).
|
|
* The data mangled in the bit stream remains in little endian
|
|
* order the whole time. It make more sense to talk about
|
|
* endianness of register values by considering a register
|
|
* a "cached" copy of the little endiad bit stream.
|
|
*/
|
|
static __inline__ void implement(__u8 *report, unsigned offset, unsigned n, __u32 value)
|
|
{
|
|
__le64 x;
|
|
u64 m = (1ULL << n) - 1;
|
|
|
|
WARN_ON(n > 32);
|
|
|
|
WARN_ON(value > m);
|
|
value &= m;
|
|
|
|
report += offset >> 3;
|
|
offset &= 7;
|
|
|
|
x = get_unaligned((__le64 *)report);
|
|
x &= cpu_to_le64(~(m << offset));
|
|
x |= cpu_to_le64(((u64) value) << offset);
|
|
put_unaligned(x, (__le64 *) report);
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
static void hid_process_event(struct hid_device *hid, struct hid_field *field, struct hid_usage *usage, __s32 value, int interrupt)
|
|
{
|
|
hid_dump_input(usage, value);
|
|
if (hid->claimed & HID_CLAIMED_INPUT)
|
|
hidinput_hid_event(hid, field, usage, value);
|
|
if (hid->claimed & HID_CLAIMED_HIDDEV && interrupt && hid->hiddev_hid_event)
|
|
hid->hiddev_hid_event(hid, field, usage, value);
|
|
}
|
|
|
|
/*
|
|
* 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).
|
|
*/
|
|
|
|
void hid_input_field(struct hid_device *hid, struct hid_field *field, __u8 *data, int interrupt)
|
|
{
|
|
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;
|
|
|
|
if (!(value = kmalloc(sizeof(__s32) * count, GFP_ATOMIC)))
|
|
return;
|
|
|
|
for (n = 0; n < count; n++) {
|
|
|
|
value[n] = min < 0 ? snto32(extract(data, offset + n * size, size), size) :
|
|
extract(data, offset + n * size, size);
|
|
|
|
if (!(field->flags & HID_MAIN_ITEM_VARIABLE) /* Ignore report if ErrorRollOver */
|
|
&& value[n] >= min && value[n] <= max
|
|
&& field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1)
|
|
goto exit;
|
|
}
|
|
|
|
for (n = 0; n < count; n++) {
|
|
|
|
if (HID_MAIN_ITEM_VARIABLE & field->flags) {
|
|
hid_process_event(hid, field, &field->usage[n], value[n], interrupt);
|
|
continue;
|
|
}
|
|
|
|
if (field->value[n] >= min && field->value[n] <= max
|
|
&& field->usage[field->value[n] - min].hid
|
|
&& search(value, field->value[n], count))
|
|
hid_process_event(hid, field, &field->usage[field->value[n] - min], 0, interrupt);
|
|
|
|
if (value[n] >= min && value[n] <= max
|
|
&& field->usage[value[n] - min].hid
|
|
&& search(field->value, value[n], count))
|
|
hid_process_event(hid, field, &field->usage[value[n] - min], 1, interrupt);
|
|
}
|
|
|
|
memcpy(field->value, value, count * sizeof(__s32));
|
|
exit:
|
|
kfree(value);
|
|
}
|
|
EXPORT_SYMBOL_GPL(hid_input_field);
|
|
|
|
/*
|
|
* 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 bitsused = offset + count * size;
|
|
unsigned n;
|
|
|
|
/* make sure the unused bits in the last byte are zeros */
|
|
if (count > 0 && size > 0 && (bitsused % 8) != 0)
|
|
data[(bitsused-1)/8] &= (1 << (bitsused % 8)) - 1;
|
|
|
|
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;
|
|
|
|
if (report->id > 0)
|
|
*data++ = report->id;
|
|
|
|
for (n = 0; n < report->maxfield; n++)
|
|
hid_output_field(report->field[n], data);
|
|
}
|
|
EXPORT_SYMBOL_GPL(hid_output_report);
|
|
|
|
/*
|
|
* Set a field value. The report this field belongs to has to be
|
|
* created and transferred 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;
|
|
|
|
hid_dump_input(field->usage + offset, value);
|
|
|
|
if (offset >= field->report_count) {
|
|
dbg("offset (%d) exceeds report_count (%d)", 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);
|
|
return -1;
|
|
}
|
|
}
|
|
field->value[offset] = value;
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(hid_set_field);
|
|
|
|
int hid_input_report(struct hid_device *hid, int type, u8 *data, int size, int interrupt)
|
|
{
|
|
struct hid_report_enum *report_enum = hid->report_enum + type;
|
|
struct hid_report *report;
|
|
int n, rsize;
|
|
|
|
if (!hid)
|
|
return -ENODEV;
|
|
|
|
if (!size) {
|
|
dbg("empty report");
|
|
return -1;
|
|
}
|
|
|
|
#ifdef CONFIG_HID_DEBUG
|
|
printk(KERN_DEBUG __FILE__ ": report (size %u) (%snumbered)\n", size, report_enum->numbered ? "" : "un");
|
|
#endif
|
|
|
|
n = 0; /* Normally report number is 0 */
|
|
if (report_enum->numbered) { /* Device uses numbered reports, data[0] is report number */
|
|
n = *data++;
|
|
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
|
|
|
|
if (!(report = report_enum->report_id_hash[n])) {
|
|
dbg("undefined report_id %d received", n);
|
|
return -1;
|
|
}
|
|
|
|
rsize = ((report->size - 1) >> 3) + 1;
|
|
|
|
if (size < rsize) {
|
|
dbg("report %d is too short, (%d < %d)", report->id, size, rsize);
|
|
memset(data + size, 0, rsize - size);
|
|
}
|
|
|
|
if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_report_event)
|
|
hid->hiddev_report_event(hid, report);
|
|
|
|
for (n = 0; n < report->maxfield; n++)
|
|
hid_input_field(hid, report->field[n], data, interrupt);
|
|
|
|
if (hid->claimed & HID_CLAIMED_INPUT)
|
|
hidinput_report_event(hid, report);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(hid_input_report);
|
|
|
|
MODULE_LICENSE(DRIVER_LICENSE);
|
|
|
|
|