From: Conor Dooley <conor.dooley@xxxxxxxxxxxxx> [ Upstream commit b5984a9844fc45cd301a28fb56f3de95f7e20f3c ] The system controller on PolarFire SoC has no interrupt to signify that the TX has been completed. The interrupt instead signals that a service requested by the mailbox client has succeeded. If a service fails, there will be no interrupt delivered. Switch to polling the busy register to determine whether transmission has completed. Fixes: 83d7b1560810 ("mbox: add polarfire soc system controller mailbox") Acked-by: Jassi Brar <jaswinder.singh@xxxxxxxxxx> Tested-by: Valentina Fernandez <valentina.fernandezalanis@xxxxxxxxxxxxx> Signed-off-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/mailbox/mailbox-mpfs.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/mailbox/mailbox-mpfs.c b/drivers/mailbox/mailbox-mpfs.c index 853901acaeec2..08aa840cccaca 100644 --- a/drivers/mailbox/mailbox-mpfs.c +++ b/drivers/mailbox/mailbox-mpfs.c @@ -79,6 +79,13 @@ static bool mpfs_mbox_busy(struct mpfs_mbox *mbox) return status & SCB_STATUS_BUSY_MASK; } +static bool mpfs_mbox_last_tx_done(struct mbox_chan *chan) +{ + struct mpfs_mbox *mbox = (struct mpfs_mbox *)chan->con_priv; + + return !mpfs_mbox_busy(mbox); +} + static int mpfs_mbox_send_data(struct mbox_chan *chan, void *data) { struct mpfs_mbox *mbox = (struct mpfs_mbox *)chan->con_priv; @@ -182,7 +189,6 @@ static irqreturn_t mpfs_mbox_inbox_isr(int irq, void *data) mpfs_mbox_rx_data(chan); - mbox_chan_txdone(chan, 0); return IRQ_HANDLED; } @@ -212,6 +218,7 @@ static const struct mbox_chan_ops mpfs_mbox_ops = { .send_data = mpfs_mbox_send_data, .startup = mpfs_mbox_startup, .shutdown = mpfs_mbox_shutdown, + .last_tx_done = mpfs_mbox_last_tx_done, }; static int mpfs_mbox_probe(struct platform_device *pdev) @@ -247,7 +254,8 @@ static int mpfs_mbox_probe(struct platform_device *pdev) mbox->controller.num_chans = 1; mbox->controller.chans = mbox->chans; mbox->controller.ops = &mpfs_mbox_ops; - mbox->controller.txdone_irq = true; + mbox->controller.txdone_poll = true; + mbox->controller.txpoll_period = 10u; ret = devm_mbox_controller_register(&pdev->dev, &mbox->controller); if (ret) { -- 2.39.2