[media] mceusb: buffer parsing fixups for 1st-gen device

If we pass in an offset, we shouldn't skip 2 bytes. And the first-gen
hardware generates a constant stream of interrupts, always with two
header bytes, and if there's been no IR, with nothing else. Bail from
ir processing without calling ir_handle_raw_event when we get such a
buffer delivered to us.

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/media/IR/mceusb.c b/drivers/media/IR/mceusb.c
index 18110987597e..ed151c8290fe 100644
--- a/drivers/media/IR/mceusb.c
+++ b/drivers/media/IR/mceusb.c
@@ -446,7 +446,7 @@ static void mceusb_dev_printdata(struct mceusb_dev *ir, char *buf,
                 return;
 
         /* skip meaningless 0xb1 0x60 header bytes on orig receiver */
-        if (ir->flags.microsoft_gen1 && !out)
+        if (ir->flags.microsoft_gen1 && !out && !offset)
                 skip = 2;
 
         if (len <= skip)
@@ -807,6 +807,10 @@ static void mceusb_process_ir_data(struct mceusb_dev *ir, int buf_len)
         if (ir->flags.microsoft_gen1)
                 i = 2;
 
+        /* if there's no data, just return now */
+        if (buf_len <= i)
+                return;
+
         for (; i < buf_len; i++) {
                 switch (ir->parser_state) {
                 case SUBCMD: