Report ID of zero is a special case handling ID-less reports and in
that case we should omit report ID from the payload being sent to the
backend.
Without this change UHID_DEV_NUMBERED_{FEATURE,OUTPUT}_REPORTS doesn't
represent a semantical difference.
Cc: David Rheinsberg <david.rheinsberg@xxxxxxxxx>
Cc: Jiri Kosina <jikos@xxxxxxxxxx>
Cc: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
Cc: linux-input@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-usb@xxxxxxxxxxxxxxx
Signed-off-by: Andrey Smirnov <andrew.smirnov@xxxxxxxxx>
---
drivers/hid/uhid.c | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/drivers/hid/uhid.c b/drivers/hid/uhid.c
index 2a918aeb0af1..7551120215e8 100644
--- a/drivers/hid/uhid.c
+++ b/drivers/hid/uhid.c
@@ -273,11 +273,11 @@ static int uhid_hid_get_report(struct hid_device *hid, unsigned char rnum,
}
static int uhid_hid_set_report(struct hid_device *hid, unsigned char rnum,
- const u8 *buf, size_t count, u8 rtype)
+ u8 *buf, size_t count, u8 rtype)
{
struct uhid_device *uhid = hid->driver_data;
struct uhid_event *ev;
- int ret;
+ int ret, skipped_report_id = 0;
if (!READ_ONCE(uhid->running) || count > UHID_DATA_MAX)
return -EIO;
@@ -286,6 +286,15 @@ static int uhid_hid_set_report(struct hid_device *hid, unsigned char rnum,
if (!ev)
return -ENOMEM;
+ /* Byte 0 is the report number. Report data starts at byte 1.*/
+ buf[0] = rnum;
+ if (buf[0] == 0x0) {
+ /* Don't send the Report ID */
+ buf++;
+ count--;
+ skipped_report_id = 1;
+ }
+
ev->type = UHID_SET_REPORT;
ev->u.set_report.rnum = rnum;
ev->u.set_report.rtype = rtype;
@@ -306,7 +315,7 @@ static int uhid_hid_set_report(struct hid_device *hid, unsigned char rnum,
if (uhid->report_buf.u.set_report_reply.err)
ret = -EIO;
else
- ret = count;
+ ret = count + skipped_report_id;
unlock:
mutex_unlock(&uhid->report_lock);
--
2.34.1
