diff options
Diffstat (limited to 'drivers/tty/serial/sh-sci.c')
| -rw-r--r-- | drivers/tty/serial/sh-sci.c | 29 |
1 files changed, 18 insertions, 11 deletions
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index cc56cb3b3eca..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) +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; @@ -1359,19 +1359,22 @@ static void sci_submit_rx(struct sci_port *s) s->active_rx = s->cookie_rx[0]; dma_async_issue_pending(chan); - return; + return 0; fail: + /* Switch to PIO */ + if (!port_lock_held) + spin_lock_irqsave(&port->lock, flags); if (i) dmaengine_terminate_async(chan); for (i = 0; i < 2; i++) s->cookie_rx[i] = -EINVAL; - s->active_rx = -EINVAL; - /* Switch to PIO */ - spin_lock_irqsave(&port->lock, flags); + s->active_rx = 0; s->chan_rx = NULL; sci_start_rx(port); - spin_unlock_irqrestore(&port->lock, flags); + if (!port_lock_held) + spin_unlock_irqrestore(&port->lock, flags); + return -EAGAIN; } static void work_fn_tx(struct work_struct *work) @@ -1491,7 +1494,7 @@ static enum hrtimer_restart rx_timer_fn(struct hrtimer *t) } if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) - sci_submit_rx(s); + sci_submit_rx(s, true); /* Direct new serial port interrupts back to CPU */ scr = serial_port_in(port, SCSCR); @@ -1617,7 +1620,7 @@ static void sci_request_dma(struct uart_port *port) s->chan_rx_saved = s->chan_rx = chan; if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) - sci_submit_rx(s); + sci_submit_rx(s, false); } } @@ -1666,8 +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); } serial_port_out(port, SCSCR, scr); /* Clear current interrupt */ @@ -1679,6 +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) { @@ -1693,7 +1700,7 @@ static irqreturn_t sci_rx_interrupt(int irq, void *ptr) * of whether the I_IXOFF is set, otherwise, how is the interrupt * to be disabled? */ - sci_receive_chars(ptr); + sci_receive_chars(port); return IRQ_HANDLED; } @@ -1749,7 +1756,7 @@ static irqreturn_t sci_er_interrupt(int irq, void *ptr) } else { sci_handle_fifo_overrun(port); if (!s->chan_rx) - sci_receive_chars(ptr); + sci_receive_chars(port); } sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port)); |