Messages in this thread Patch in this message | | | From | Sebastian Andrzej Siewior <> | Subject | [PATCH 3/7] serial: 8250_dma: continue TX dma on dma error | Date | Tue, 29 Jul 2014 20:59:00 +0200 |
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After TX dma completes the code will queue another DMA transfer. If serial8250_tx_dma() fails then there is no plan B to continue the transfer manually. This patch enables the TX-fifo empty event so it can be tried again via DMA or use the manual fallback in case it fails.
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- drivers/tty/serial/8250/8250_dma.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c index 148ffe4..f9ef69f 100644 --- a/drivers/tty/serial/8250/8250_dma.c +++ b/drivers/tty/serial/8250/8250_dma.c @@ -36,8 +36,15 @@ static void __dma_tx_complete(void *param) if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) uart_write_wakeup(&p->port); - if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) - serial8250_tx_dma(p); + if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) { + int ret; + + ret = serial8250_tx_dma(p); + if (ret && !(p->ier & UART_IER_THRI)) { + p->ier |= UART_IER_THRI; + serial_port_out(&p->port, UART_IER, p->ier); + } + } spin_unlock_irqrestore(&p->port.lock, flags); } -- 2.0.1
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