diff options
| author | Peter Hurley <peter@hurleysoftware.com> | 2016-04-09 22:14:36 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-04-30 09:26:55 -0700 |
| commit | 33d9b8b23a73d5d8609a740d0adeea8235c2ae52 (patch) | |
| tree | ef63a64eb25995cc3dd6f9912ced54560275e71c /drivers/tty/serial/8250/8250_port.c | |
| parent | b74fdd23d8fb4e349185ed9d963da8fc2b6eb34c (diff) | |
serial: 8250: Extract IIR logic steering from rx dma
Using fake IIR values to perform rx dma operations unnecessarily
conflates separate operations, stopping in-progress dma with starting
new dma.
Introduce serial8250_rx_dma_flush() to handle stopping in-progress dma
[omap8250 already has equivalent omap_8250_rx_dma_flush()].
Replace rx_dma(UART_IIR_RX_TIMEOUT) with the equivalent *_rx_dma_flush(),
and rx_dma(0) with the equivalent *_rx_dma(). Handle IIR steering
in the irq handler with handle_rx_dma() helper.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/8250/8250_port.c')
| -rw-r--r-- | drivers/tty/serial/8250/8250_port.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index b2bbb9dcfa0b..215e8da78a06 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -1788,6 +1788,18 @@ unsigned int serial8250_modem_status(struct uart_8250_port *up) } EXPORT_SYMBOL_GPL(serial8250_modem_status); +static bool handle_rx_dma(struct uart_8250_port *up, unsigned int iir) +{ + switch (iir & 0x3f) { + case UART_IIR_RX_TIMEOUT: + serial8250_rx_dma_flush(up); + /* fall-through */ + case UART_IIR_RLSI: + return true; + } + return up->dma->rx_dma(up); +} + /* * This handles the interrupt from one port. */ @@ -1807,7 +1819,7 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir) DEBUG_INTR("status = %x...", status); if (status & (UART_LSR_DR | UART_LSR_BI)) { - if (!up->dma || up->dma->rx_dma(up, iir)) + if (!up->dma || handle_rx_dma(up, iir)) status = serial8250_rx_chars(up, status); } serial8250_modem_status(up); |