HID: Use hid_parser for pre-scanning the report descriptors
The Win 8 detection is sufficiently complex to warrant use of the full parser code, in spite of the inferred memory usage. Therefore, we can use the existing HID parser in hid-core for hid_scan_report() by re-using the code from hid_open_report(). hid_parser_global, hid_parser_local and hid_parser_reserved does not have any side effects. We just need to reimplement the MAIN_ITEM callback to have a proper parsing without side effects. Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Reviewed-by: Henrik Rydberg <rydberg@euromail.se> Tested-by: Srinivas Pandruvada<srinivas.pandruvada@linux.intel.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
Benjamin Tissoires
Jiri Kosina
parent
c08d46aa80
commit
3dc8fc083d
1 changed files with 64 additions and 38 deletions
|
|
@ -677,12 +677,52 @@ static u8 *fetch_item(__u8 *start, __u8 *end, struct hid_item *item)
|
||||||
return NULL;
|
return NULL;
|
||||||
}
|
}
|
||||||
|
|
||||||
static void hid_scan_usage(struct hid_device *hid, u32 usage)
|
static void hid_scan_input_usage(struct hid_parser *parser, u32 usage)
|
||||||
{
|
{
|
||||||
|
struct hid_device *hid = parser->device;
|
||||||
|
|
||||||
if (usage == HID_DG_CONTACTID)
|
if (usage == HID_DG_CONTACTID)
|
||||||
hid->group = HID_GROUP_MULTITOUCH;
|
hid->group = HID_GROUP_MULTITOUCH;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
static void hid_scan_collection(struct hid_parser *parser, unsigned type)
|
||||||
|
{
|
||||||
|
struct hid_device *hid = parser->device;
|
||||||
|
|
||||||
|
if (((parser->global.usage_page << 16) == HID_UP_SENSOR) &&
|
||||||
|
type == HID_COLLECTION_PHYSICAL)
|
||||||
|
hid->group = HID_GROUP_SENSOR_HUB;
|
||||||
|
}
|
||||||
|
|
||||||
|
static int hid_scan_main(struct hid_parser *parser, struct hid_item *item)
|
||||||
|
{
|
||||||
|
__u32 data;
|
||||||
|
int i;
|
||||||
|
|
||||||
|
data = item_udata(item);
|
||||||
|
|
||||||
|
switch (item->tag) {
|
||||||
|
case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
|
||||||
|
hid_scan_collection(parser, data & 0xff);
|
||||||
|
break;
|
||||||
|
case HID_MAIN_ITEM_TAG_END_COLLECTION:
|
||||||
|
break;
|
||||||
|
case HID_MAIN_ITEM_TAG_INPUT:
|
||||||
|
for (i = 0; i < parser->local.usage_index; i++)
|
||||||
|
hid_scan_input_usage(parser, parser->local.usage[i]);
|
||||||
|
break;
|
||||||
|
case HID_MAIN_ITEM_TAG_OUTPUT:
|
||||||
|
break;
|
||||||
|
case HID_MAIN_ITEM_TAG_FEATURE:
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Reset the local parser environment */
|
||||||
|
memset(&parser->local, 0, sizeof(parser->local));
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
/*
|
/*
|
||||||
* Scan a report descriptor before the device is added to the bus.
|
* Scan a report descriptor before the device is added to the bus.
|
||||||
* Sets device groups and other properties that determine what driver
|
* Sets device groups and other properties that determine what driver
|
||||||
|
|
@ -690,48 +730,34 @@ static void hid_scan_usage(struct hid_device *hid, u32 usage)
|
||||||
*/
|
*/
|
||||||
static int hid_scan_report(struct hid_device *hid)
|
static int hid_scan_report(struct hid_device *hid)
|
||||||
{
|
{
|
||||||
unsigned int page = 0, delim = 0;
|
struct hid_parser *parser;
|
||||||
|
struct hid_item item;
|
||||||
__u8 *start = hid->dev_rdesc;
|
__u8 *start = hid->dev_rdesc;
|
||||||
__u8 *end = start + hid->dev_rsize;
|
__u8 *end = start + hid->dev_rsize;
|
||||||
unsigned int u, u_min = 0, u_max = 0;
|
static int (*dispatch_type[])(struct hid_parser *parser,
|
||||||
struct hid_item item;
|
struct hid_item *item) = {
|
||||||
|
hid_scan_main,
|
||||||
|
hid_parser_global,
|
||||||
|
hid_parser_local,
|
||||||
|
hid_parser_reserved
|
||||||
|
};
|
||||||
|
|
||||||
|
parser = vzalloc(sizeof(struct hid_parser));
|
||||||
|
if (!parser)
|
||||||
|
return -ENOMEM;
|
||||||
|
|
||||||
|
parser->device = hid;
|
||||||
hid->group = HID_GROUP_GENERIC;
|
hid->group = HID_GROUP_GENERIC;
|
||||||
while ((start = fetch_item(start, end, &item)) != NULL) {
|
|
||||||
if (item.format != HID_ITEM_FORMAT_SHORT)
|
|
||||||
return -EINVAL;
|
|
||||||
if (item.type == HID_ITEM_TYPE_GLOBAL) {
|
|
||||||
if (item.tag == HID_GLOBAL_ITEM_TAG_USAGE_PAGE)
|
|
||||||
page = item_udata(&item) << 16;
|
|
||||||
} else if (item.type == HID_ITEM_TYPE_LOCAL) {
|
|
||||||
if (delim > 1)
|
|
||||||
break;
|
|
||||||
u = item_udata(&item);
|
|
||||||
if (item.size <= 2)
|
|
||||||
u += page;
|
|
||||||
switch (item.tag) {
|
|
||||||
case HID_LOCAL_ITEM_TAG_DELIMITER:
|
|
||||||
delim += !!u;
|
|
||||||
break;
|
|
||||||
case HID_LOCAL_ITEM_TAG_USAGE:
|
|
||||||
hid_scan_usage(hid, u);
|
|
||||||
break;
|
|
||||||
case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM:
|
|
||||||
u_min = u;
|
|
||||||
break;
|
|
||||||
case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM:
|
|
||||||
u_max = u;
|
|
||||||
for (u = u_min; u <= u_max; u++)
|
|
||||||
hid_scan_usage(hid, u);
|
|
||||||
break;
|
|
||||||
}
|
|
||||||
} else if (page == HID_UP_SENSOR &&
|
|
||||||
item.type == HID_ITEM_TYPE_MAIN &&
|
|
||||||
item.tag == HID_MAIN_ITEM_TAG_BEGIN_COLLECTION &&
|
|
||||||
(item_udata(&item) & 0xff) == HID_COLLECTION_PHYSICAL)
|
|
||||||
hid->group = HID_GROUP_SENSOR_HUB;
|
|
||||||
}
|
|
||||||
|
|
||||||
|
/*
|
||||||
|
* The parsing is simpler than the one in hid_open_report() as we should
|
||||||
|
* be robust against hid errors. Those errors will be raised by
|
||||||
|
* hid_open_report() anyway.
|
||||||
|
*/
|
||||||
|
while ((start = fetch_item(start, end, &item)) != NULL)
|
||||||
|
dispatch_type[item.type](parser, &item);
|
||||||
|
|
||||||
|
vfree(parser);
|
||||||
return 0;
|
return 0;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
|
||||||
Loading…
Add table
Reference in a new issue