-
-/*
- * Register a new report for a device.
- */
-
-static struct hid_report *hid_register_report(struct hid_device *device, unsigned type, unsigned id)
-{
- struct hid_report_enum *report_enum = device->report_enum + type;
- struct hid_report *report;
-
- if (report_enum->report_id_hash[id])
- return report_enum->report_id_hash[id];
-
- if (!(report = kmalloc(sizeof(struct hid_report), GFP_KERNEL)))
- return NULL;
- memset(report, 0, sizeof(struct hid_report));
-
- if (id != 0)
- report_enum->numbered = 1;
-
- report->id = id;
- report->type = type;
- report->size = 0;
- report->device = device;
- report_enum->report_id_hash[id] = report;
-
- list_add_tail(&report->list, &report_enum->report_list);
-
- return report;
-}
-
-/*
- * Register a new field for this report.
- */
-
-static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages, unsigned values)
-{
- struct hid_field *field;
-
- if (report->maxfield == HID_MAX_FIELDS) {
- dbg("too many fields in report");
- return NULL;
- }
-
- if (!(field = kmalloc(sizeof(struct hid_field) + usages * sizeof(struct hid_usage)
- + values * sizeof(unsigned), GFP_KERNEL))) return NULL;
-
- memset(field, 0, sizeof(struct hid_field) + usages * sizeof(struct hid_usage)
- + values * sizeof(unsigned));
-
- report->field[report->maxfield++] = field;
- field->usage = (struct hid_usage *)(field + 1);
- field->value = (unsigned *)(field->usage + usages);
- field->report = report;
-
- return field;
-}
-
-/*
- * Open a collection. The type/usage is pushed on the stack.
- */
-
-static int open_collection(struct hid_parser *parser, unsigned type)
-{
- struct hid_collection *collection;
- unsigned usage;
-
- usage = parser->local.usage[0];
-
- if (parser->collection_stack_ptr == HID_COLLECTION_STACK_SIZE) {
- dbg("collection stack overflow");
- return -1;
- }
-
- if (parser->device->maxcollection == parser->device->collection_size) {
- collection = kmalloc(sizeof(struct hid_collection) *
- parser->device->collection_size * 2,
- GFP_KERNEL);
- if (collection == NULL) {
- dbg("failed to reallocate collection array");
- return -1;
- }
- memcpy(collection, parser->device->collection,
- sizeof(struct hid_collection) *
- parser->device->collection_size);
- memset(collection + parser->device->collection_size, 0,
- sizeof(struct hid_collection) *
- parser->device->collection_size);
- kfree(parser->device->collection);
- parser->device->collection = collection;
- parser->device->collection_size *= 2;
- }
-
- parser->collection_stack[parser->collection_stack_ptr++] =
- parser->device->maxcollection;
-
- collection = parser->device->collection +
- parser->device->maxcollection++;
- collection->type = type;
- collection->usage = usage;
- collection->level = parser->collection_stack_ptr - 1;
-
- if (type == HID_COLLECTION_APPLICATION)
- parser->device->maxapplication++;
-
- return 0;
-}
-
-/*
- * Close a collection.
- */
-
-static int close_collection(struct hid_parser *parser)
-{
- if (!parser->collection_stack_ptr) {
- dbg("collection stack underflow");
- return -1;
- }
- parser->collection_stack_ptr--;
- return 0;
-}
-
-/*
- * Climb up the stack, search for the specified collection type
- * and return the usage.
- */
-
-static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type)
-{
- int n;
- for (n = parser->collection_stack_ptr - 1; n >= 0; n--)
- if (parser->device->collection[parser->collection_stack[n]].type == type)
- return parser->device->collection[parser->collection_stack[n]].usage;
- return 0; /* we know nothing about this usage type */
-}
-
-/*
- * Add a usage to the temporary parser table.
- */
-
-static int hid_add_usage(struct hid_parser *parser, unsigned usage)
-{
- if (parser->local.usage_index >= HID_MAX_USAGES) {
- dbg("usage index exceeded");
- return -1;
- }
- parser->local.usage[parser->local.usage_index] = usage;
- parser->local.collection_index[parser->local.usage_index] =
- parser->collection_stack_ptr ?
- parser->collection_stack[parser->collection_stack_ptr - 1] : 0;
- parser->local.usage_index++;
- return 0;
-}
-
-/*
- * Register a new field for this report.
- */
-
-static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsigned flags)
-{
- struct hid_report *report;
- struct hid_field *field;
- int usages;
- unsigned offset;
- int i;
-
- if (!(report = hid_register_report(parser->device, report_type, parser->global.report_id))) {
- dbg("hid_register_report failed");
- return -1;
- }
-
- if (parser->global.logical_maximum < parser->global.logical_minimum) {
- dbg("logical range invalid %d %d", parser->global.logical_minimum, parser->global.logical_maximum);
- return -1;
- }
- usages = parser->local.usage_index;
-
- offset = report->size;
- report->size += parser->global.report_size * parser->global.report_count;
-
- if (usages < parser->global.report_count)
- usages = parser->global.report_count;
-
- if (usages == 0)
- return 0; /* ignore padding fields */
-
- if ((field = hid_register_field(report, usages, parser->global.report_count)) == NULL)
- return 0;
-
- field->physical = hid_lookup_collection(parser, HID_COLLECTION_PHYSICAL);
- field->logical = hid_lookup_collection(parser, HID_COLLECTION_LOGICAL);
- field->application = hid_lookup_collection(parser, HID_COLLECTION_APPLICATION);
-
- for (i = 0; i < usages; i++) {
- int j = i;
- /* Duplicate the last usage we parsed if we have excess values */
- if (i >= parser->local.usage_index)
- j = parser->local.usage_index - 1;
- field->usage[i].hid = parser->local.usage[j];
- field->usage[i].collection_index =
- parser->local.collection_index[j];
- }
-
- field->maxusage = usages;
- field->flags = flags;
- field->report_offset = offset;
- field->report_type = report_type;
- field->report_size = parser->global.report_size;
- field->report_count = parser->global.report_count;
- field->logical_minimum = parser->global.logical_minimum;
- field->logical_maximum = parser->global.logical_maximum;
- field->physical_minimum = parser->global.physical_minimum;
- field->physical_maximum = parser->global.physical_maximum;
- field->unit_exponent = parser->global.unit_exponent;
- field->unit = parser->global.unit;
-
- return 0;
-}
-
-/*
- * Read data value from item.
- */
-
-static __inline__ __u32 item_udata(struct hid_item *item)
-{
- switch (item->size) {
- case 1: return item->data.u8;
- case 2: return item->data.u16;
- case 4: return item->data.u32;
- }
- return 0;
-}
-
-static __inline__ __s32 item_sdata(struct hid_item *item)
-{
- switch (item->size) {
- case 1: return item->data.s8;
- case 2: return item->data.s16;
- case 4: return item->data.s32;
- }
- return 0;
-}
-
-/*
- * Process a global item.
- */
-
-static int hid_parser_global(struct hid_parser *parser, struct hid_item *item)
-{
- switch (item->tag) {
-
- case HID_GLOBAL_ITEM_TAG_PUSH:
-
- if (parser->global_stack_ptr == HID_GLOBAL_STACK_SIZE) {
- dbg("global enviroment stack overflow");
- return -1;
- }
-
- memcpy(parser->global_stack + parser->global_stack_ptr++,
- &parser->global, sizeof(struct hid_global));
- return 0;
-
- case HID_GLOBAL_ITEM_TAG_POP:
-
- if (!parser->global_stack_ptr) {
- dbg("global enviroment stack underflow");
- return -1;
- }
-
- memcpy(&parser->global, parser->global_stack + --parser->global_stack_ptr,
- sizeof(struct hid_global));
- return 0;
-
- case HID_GLOBAL_ITEM_TAG_USAGE_PAGE:
- parser->global.usage_page = item_udata(item);
- return 0;
-
- case HID_GLOBAL_ITEM_TAG_LOGICAL_MINIMUM:
- parser->global.logical_minimum = item_sdata(item);
- return 0;
-
- case HID_GLOBAL_ITEM_TAG_LOGICAL_MAXIMUM:
- if (parser->global.logical_minimum < 0)
- parser->global.logical_maximum = item_sdata(item);
- else
- parser->global.logical_maximum = item_udata(item);
- return 0;
-
- case HID_GLOBAL_ITEM_TAG_PHYSICAL_MINIMUM:
- parser->global.physical_minimum = item_sdata(item);
- return 0;
-
- case HID_GLOBAL_ITEM_TAG_PHYSICAL_MAXIMUM:
- if (parser->global.physical_minimum < 0)
- parser->global.physical_maximum = item_sdata(item);
- else
- parser->global.physical_maximum = item_udata(item);
- return 0;
-
- case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT:
- parser->global.unit_exponent = item_sdata(item);
- return 0;
-
- case HID_GLOBAL_ITEM_TAG_UNIT:
- parser->global.unit = item_udata(item);
- return 0;
-
- case HID_GLOBAL_ITEM_TAG_REPORT_SIZE:
- if ((parser->global.report_size = item_udata(item)) > 32) {
- dbg("invalid report_size %d", parser->global.report_size);
- return -1;
- }
- return 0;
-
- case HID_GLOBAL_ITEM_TAG_REPORT_COUNT:
- if ((parser->global.report_count = item_udata(item)) > HID_MAX_USAGES) {
- dbg("invalid report_count %d", parser->global.report_count);
- return -1;
- }
- return 0;
-
- case HID_GLOBAL_ITEM_TAG_REPORT_ID:
- if ((parser->global.report_id = item_udata(item)) == 0) {
- dbg("report_id 0 is invalid");
- return -1;
- }
- return 0;
-
- default:
- dbg("unknown global tag 0x%x", item->tag);
- return -1;
- }
-}
-
-/*
- * Process a local item.
- */
-
-static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
-{
- __u32 data;
- unsigned n;
-
- if (item->size == 0) {
- dbg("item data expected for local item");
- return -1;
- }
-
- data = item_udata(item);
-
- switch (item->tag) {
-
- case HID_LOCAL_ITEM_TAG_DELIMITER:
-
- if (data) {
- /*
- * We treat items before the first delimiter
- * as global to all usage sets (branch 0).
- * In the moment we process only these global
- * items and the first delimiter set.
- */
- if (parser->local.delimiter_depth != 0) {
- dbg("nested delimiters");
- return -1;
- }
- parser->local.delimiter_depth++;
- parser->local.delimiter_branch++;
- } else {
- if (parser->local.delimiter_depth < 1) {
- dbg("bogus close delimiter");
- return -1;
- }
- parser->local.delimiter_depth--;
- }
- return 1;
-
- case HID_LOCAL_ITEM_TAG_USAGE:
-
- if (parser->local.delimiter_branch > 1) {
- dbg("alternative usage ignored");
- return 0;
- }
-
- if (item->size <= 2)
- data = (parser->global.usage_page << 16) + data;
-
- return hid_add_usage(parser, data);
-
- case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM:
-
- if (parser->local.delimiter_branch > 1) {
- dbg("alternative usage ignored");
- return 0;
- }
-
- if (item->size <= 2)
- data = (parser->global.usage_page << 16) + data;
-
- parser->local.usage_minimum = data;
- return 0;
-
- case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM:
-
- if (parser->local.delimiter_branch > 1) {
- dbg("alternative usage ignored");
- return 0;
- }
-
- if (item->size <= 2)
- data = (parser->global.usage_page << 16) + data;
-
- for (n = parser->local.usage_minimum; n <= data; n++)
- if (hid_add_usage(parser, n)) {
- dbg("hid_add_usage failed\n");
- return -1;
- }
- return 0;
-
- default:
-
- dbg("unknown local item tag 0x%x", item->tag);
- return 0;
- }
- return 0;
-}
-