From: Pekka Pessi <ppessi@xxxxxxxxxx> The txdone can re-fill the mailbox. Keep polling the mailbox during the flush until all the messages have been delivered. Signed-off-by: Pekka Pessi <ppessi@xxxxxxxxxx> Signed-off-by: Thierry Reding <treding@xxxxxxxxxx> --- drivers/mailbox/tegra-hsp.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/mailbox/tegra-hsp.c b/drivers/mailbox/tegra-hsp.c index acd0675da681..78f7265039c6 100644 --- a/drivers/mailbox/tegra-hsp.c +++ b/drivers/mailbox/tegra-hsp.c @@ -412,6 +412,11 @@ static int tegra_hsp_mailbox_flush(struct mbox_chan *chan, value = tegra_hsp_channel_readl(ch, HSP_SM_SHRD_MBOX); if ((value & HSP_SM_SHRD_MBOX_FULL) == 0) { mbox_chan_txdone(chan, 0); + + /* Wait until channel is empty */ + if (chan->active_req != NULL) + continue; + return 0; } -- 2.35.1