From 0e840ed59ba79670b66bba8c1d50b6f67e72d3fb Mon Sep 17 00:00:00 2001 From: "Mark A. Greer" Date: Tue, 2 Sep 2014 15:12:29 -0700 Subject: [PATCH] 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 Signed-off-by: Samuel Ortiz --- drivers/nfc/trf7970a.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c index 8a13daf97747..e9e961fe6756 100644 --- a/drivers/nfc/trf7970a.c +++ b/drivers/nfc/trf7970a.c @@ -580,6 +580,12 @@ static void trf7970a_fill_fifo(struct trf7970a *trf) /* 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;