NFC: trf7970a: Only fill FIFO if there is space
Handle the case where trf7970a_fill_fifo() is
called but there is no room in the FIFO for
more TX data. When this happens, wait for
another interrupt indicating that there is
now space (and set a timer in case that
interrupt never occurs).
Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
index 8a13daf..e9e961f 100644
--- a/drivers/nfc/trf7970a.c
+++ b/drivers/nfc/trf7970a.c
@@ -580,6 +580,12 @@
/* Calculate how much more data can be written to the fifo */
len = TRF7970A_FIFO_SIZE - fifo_bytes;
+ if (!len) {
+ schedule_delayed_work(&trf->timeout_work,
+ msecs_to_jiffies(TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT));
+ return;
+ }
+
len = min(skb->len, len);
prefix = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_FIFO_IO_REGISTER;