[PATCH v2] mailbox: pcc: Notify clients on polled completion

[Sudeep Holla <sudeep.holla@kernel.org>]

PCC channels without a platform interrupt rely on the mailbox
polling path to detect command completion.

That path currently only reports transmit completion to the mailbox
core, so clients that wait for their receive callback do not get
notified when the command completes.

Call mbox_chan_received_data() when polling observes completion on a
channel without a platform IRQ, matching the interrupt-driven
completion path.

Reported-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@kernel.org>
---
v1->v2:
	- Check if MBOX_TXDONE_BY_POLL instead of absence of pchan->plat_irq

v1: https://patch.msgid.link/20260612170225.1063902-1-sudeep.holla@kernel.org

 drivers/mailbox/pcc.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c
index bde5e0852157..bb55f15edae3 100644
--- a/drivers/mailbox/pcc.c
+++ b/drivers/mailbox/pcc.c
@@ -490,7 +490,15 @@ static bool pcc_last_tx_done(struct mbox_chan *chan)
 {
 	struct pcc_chan_info *pchan = chan->con_priv;
 
-	return pcc_mbox_cmd_complete_check(pchan);
+	if (!(chan->txdone_method & MBOX_TXDONE_BY_POLL))
+		return false;
+
+	if (!pcc_mbox_cmd_complete_check(pchan))
+		return false;
+
+	mbox_chan_received_data(chan, NULL);
+
+	return true;
 }
 
 /**
-- 
2.43.0