![Jiri Kosina](/assets/img/avatar_default.png)
There have been many reports recently about broken HID devices, the diagnosis of which required users to recompile their kernels in order to be able to provide debugging output needed for coding a quirk for a particular device. This patch makes CONFIG_HID_DEBUG default y if !EMBEDDED and makes it possible to control debugging output produced by HID code by supplying 'debug=1' module parameter. Signed-off-by: Jiri Kosina <jkosina@suse.cz>
995 lines
24 KiB
C
995 lines
24 KiB
C
/*
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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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#ifdef CONFIG_HID_DEBUG
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int hid_debug = 0;
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module_param_named(debug, hid_debug, bool, 0600);
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MODULE_PARM_DESC(debug, "Turn HID debugging mode on and off");
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EXPORT_SYMBOL_GPL(hid_debug);
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#endif
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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_hid("too many fields in report\n");
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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_hid("collection stack overflow\n");
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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_hid("failed to reallocate collection array\n");
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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_hid("collection stack underflow\n");
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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_hid("usage index exceeded\n");
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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("hid_register_report failed\n");
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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_hid("logical range invalid %d %d\n", 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_hid("global enviroment stack overflow\n");
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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_hid("global enviroment stack underflow\n");
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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_hid("invalid report_size %d\n", 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_hid("invalid report_count %d\n", 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_hid("report_id 0 is invalid\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_hid("unknown global tag 0x%x\n", 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_hid("item data expected for local item\n");
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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_hid("nested delimiters\n");
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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_hid("bogus close delimiter\n");
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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_hid("alternative usage ignored\n");
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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_hid("alternative usage ignored\n");
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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_hid("alternative usage ignored\n");
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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("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_hid("unknown local item tag 0x%x\n", 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_hid("unknown main item tag 0x%x\n", 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_hid("reserved item type, tag 0x%x\n", 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++) {
|
|
struct hid_report *report = report_enum->report_id_hash[j];
|
|
if (report)
|
|
hid_free_report(report);
|
|
}
|
|
}
|
|
|
|
kfree(device->rdesc);
|
|
kfree(device->collection);
|
|
kfree(device);
|
|
}
|
|
EXPORT_SYMBOL_GPL(hid_free_device);
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
u8 b;
|
|
|
|
if ((end - start) <= 0)
|
|
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_hid("unexpected long global item\n");
|
|
hid_free_device(device);
|
|
vfree(parser);
|
|
return NULL;
|
|
}
|
|
|
|
if (dispatch_type[item.type](parser, &item)) {
|
|
dbg_hid("item %u %u %u %u parsing failed\n",
|
|
item.format, (unsigned)item.size, (unsigned)item.type, (unsigned)item.tag);
|
|
hid_free_device(device);
|
|
vfree(parser);
|
|
return NULL;
|
|
}
|
|
|
|
if (start == end) {
|
|
if (parser->collection_stack_ptr) {
|
|
dbg_hid("unbalanced collection at end of report description\n");
|
|
hid_free_device(device);
|
|
vfree(parser);
|
|
return NULL;
|
|
}
|
|
if (parser->local.delimiter_depth) {
|
|
dbg_hid("unbalanced delimiter at end of report description\n");
|
|
hid_free_device(device);
|
|
vfree(parser);
|
|
return NULL;
|
|
}
|
|
vfree(parser);
|
|
return device;
|
|
}
|
|
}
|
|
|
|
dbg_hid("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_hid("offset (%d) exceeds report_count (%d)\n", offset, field->report_count);
|
|
hid_dump_field(field, 8);
|
|
return -1;
|
|
}
|
|
if (field->logical_minimum < 0) {
|
|
if (value != snto32(s32ton(value, size), size)) {
|
|
dbg_hid("value %d is out of range\n", 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, i;
|
|
|
|
if (!hid)
|
|
return -ENODEV;
|
|
|
|
if (!size) {
|
|
dbg_hid("empty report\n");
|
|
return -1;
|
|
}
|
|
|
|
dbg_hid("report (size %u) (%snumbered)\n", size, report_enum->numbered ? "" : "un");
|
|
|
|
n = 0; /* Normally report number is 0 */
|
|
if (report_enum->numbered) { /* Device uses numbered reports, data[0] is report number */
|
|
n = *data++;
|
|
size--;
|
|
}
|
|
|
|
/* dump the report descriptor */
|
|
dbg_hid("report %d (size %u) = ", n, size);
|
|
for (i = 0; i < size; i++)
|
|
dbg_hid_line(" %02x", data[i]);
|
|
dbg_hid_line("\n");
|
|
|
|
if (!(report = report_enum->report_id_hash[n])) {
|
|
dbg_hid("undefined report_id %d received\n", n);
|
|
return -1;
|
|
}
|
|
|
|
rsize = ((report->size - 1) >> 3) + 1;
|
|
|
|
if (size < rsize) {
|
|
dbg_hid("report %d is too short, (%d < %d)\n", 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);
|
|
|