diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 9993b692598f..852bbd303d9a 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -218,13 +218,14 @@ static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type) * Add a usage to the temporary parser table. */ -static int hid_add_usage(struct hid_parser *parser, unsigned usage) +static int hid_add_usage(struct hid_parser *parser, unsigned usage, u8 size) { if (parser->local.usage_index >= HID_MAX_USAGES) { hid_err(parser->device, "usage index exceeded\n"); return -1; } parser->local.usage[parser->local.usage_index] = usage; + parser->local.usage_size[parser->local.usage_index] = size; parser->local.collection_index[parser->local.usage_index] = parser->collection_stack_ptr ? parser->collection_stack[parser->collection_stack_ptr - 1] : 0; @@ -486,10 +487,7 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) return 0; } - if (item->size <= 2) - data = (parser->global.usage_page << 16) + data; - - return hid_add_usage(parser, data); + return hid_add_usage(parser, data, item->size); case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM: @@ -498,9 +496,6 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) return 0; } - if (item->size <= 2) - data = (parser->global.usage_page << 16) + data; - parser->local.usage_minimum = data; return 0; @@ -511,9 +506,6 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) return 0; } - if (item->size <= 2) - data = (parser->global.usage_page << 16) + data; - count = data - parser->local.usage_minimum; if (count + parser->local.usage_index >= HID_MAX_USAGES) { /* @@ -533,7 +525,7 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) } for (n = parser->local.usage_minimum; n <= data; n++) - if (hid_add_usage(parser, n)) { + if (hid_add_usage(parser, n, item->size)) { dbg_hid("hid_add_usage failed\n"); return -1; } @@ -547,6 +539,22 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) return 0; } +/* + * Concatenate Usage Pages into Usages where relevant: + * As per specification, 6.2.2.8: "When the parser encounters a main item it + * concatenates the last declared Usage Page with a Usage to form a complete + * usage value." + */ + +static void hid_concatenate_usage_page(struct hid_parser *parser) +{ + int i; + + for (i = 0; i < parser->local.usage_index; i++) + if (parser->local.usage_size[i] <= 2) + parser->local.usage[i] += parser->global.usage_page << 16; +} + /* * Process a main item. */ @@ -556,6 +564,8 @@ static int hid_parser_main(struct hid_parser *parser, struct hid_item *item) __u32 data; int ret; + hid_concatenate_usage_page(parser); + data = item_udata(item); switch (item->tag) { @@ -765,6 +775,8 @@ static int hid_scan_main(struct hid_parser *parser, struct hid_item *item) __u32 data; int i; + hid_concatenate_usage_page(parser); + data = item_udata(item); switch (item->tag) { diff --git a/include/linux/hid.h b/include/linux/hid.h index f9707d1dcb58..ac0c70b4ce10 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -417,6 +417,7 @@ struct hid_global { struct hid_local { unsigned usage[HID_MAX_USAGES]; /* usage array */ + u8 usage_size[HID_MAX_USAGES]; /* usage size array */ unsigned collection_index[HID_MAX_USAGES]; /* collection index array */ unsigned usage_index; unsigned usage_minimum;