diff options
| author | Geert Uytterhoeven <geert+renesas@glider.be> | 2018-12-13 19:44:43 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-12-17 15:04:11 +0100 |
| commit | 71ab1c0336c71ace5725740f200beca9667a339f (patch) | |
| tree | fafea1d11893facf26a3602a194f46869208fafe /drivers/tty/serial | |
| parent | 2e948218b7c1262a3830823d6620eb227e3d4e3a (diff) | |
| download | linux-71ab1c0336c71ace5725740f200beca9667a339f.tar.bz2 | |
serial: sh-sci: Resume PIO in sci_rx_interrupt() on DMA failure
On (H)SCIF, sci_submit_rx() is called in the receive interrupt handler.
Hence if DMA submission fails, the interrupt handler should resume
handling reception using PIO, else no more data is received.
Make sci_submit_rx() return an error indicator, so the receive interrupt
handler can act appropriately.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial')
| -rw-r--r-- | drivers/tty/serial/sh-sci.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index e353e03ce260..8df0fd824520 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -1331,7 +1331,7 @@ static void sci_tx_dma_release(struct sci_port *s) dma_release_channel(chan); } -static void sci_submit_rx(struct sci_port *s, bool port_lock_held) +static int sci_submit_rx(struct sci_port *s, bool port_lock_held) { struct dma_chan *chan = s->chan_rx; struct uart_port *port = &s->port; @@ -1359,7 +1359,7 @@ static void sci_submit_rx(struct sci_port *s, bool port_lock_held) s->active_rx = s->cookie_rx[0]; dma_async_issue_pending(chan); - return; + return 0; fail: /* Switch to PIO */ @@ -1374,6 +1374,7 @@ fail: sci_start_rx(port); if (!port_lock_held) spin_unlock_irqrestore(&port->lock, flags); + return -EAGAIN; } static void work_fn_tx(struct work_struct *work) @@ -1668,8 +1669,10 @@ static irqreturn_t sci_rx_interrupt(int irq, void *ptr) disable_irq_nosync(irq); scr |= SCSCR_RDRQE; } else { + if (sci_submit_rx(s, false) < 0) + goto handle_pio; + scr &= ~SCSCR_RIE; - sci_submit_rx(s, false); } serial_port_out(port, SCSCR, scr); /* Clear current interrupt */ @@ -1681,6 +1684,8 @@ static irqreturn_t sci_rx_interrupt(int irq, void *ptr) return IRQ_HANDLED; } + +handle_pio: #endif if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0) { |