diff options
| author | Andy Shevchenko <andriy.shevchenko@linux.intel.com> | 2016-11-14 12:26:52 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-11-16 10:57:26 +0100 |
| commit | 5fe86674840c6773d09943a78a5f7f3bf2420ffd (patch) | |
| tree | f0c2894bde0779a6eedd30802bb2aed8652a3a13 /drivers/tty | |
| parent | 7d4e00c6253bc57b1ac0764ca76d4a8642354b54 (diff) | |
| download | linux-5fe86674840c6773d09943a78a5f7f3bf2420ffd.tar.bz2 | |
serial: 8250_dma: power off device after TX is done
When any 8250 based driver sets up DMA and has UART_CAP_RPM capability enabled
the device is left powered on after transfer is done. We need to schedule a
device suspend operation when DMA completes the transfer.
The patch is based on the work done by the reporter.
Reported-by: Huiquan Zhong <huiquan.zhong@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/8250/8250_dma.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c index fdbddbc6375d..26f17456b0d7 100644 --- a/drivers/tty/serial/8250/8250_dma.c +++ b/drivers/tty/serial/8250/8250_dma.c @@ -72,10 +72,15 @@ int serial8250_tx_dma(struct uart_8250_port *p) struct dma_async_tx_descriptor *desc; int ret; - if (uart_tx_stopped(&p->port) || dma->tx_running || - uart_circ_empty(xmit)) + if (dma->tx_running) return 0; + if (uart_tx_stopped(&p->port) || uart_circ_empty(xmit)) { + /* We have been called from __dma_tx_complete() */ + serial8250_rpm_put_tx(p); + return 0; + } + dma->tx_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); desc = dmaengine_prep_slave_single(dma->txchan, |