diff options
| author | Geert Uytterhoeven <geert+renesas@glider.be> | 2015-08-21 20:02:48 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-10-04 17:33:48 +0100 |
| commit | 47aceb927fffa77b0328b6fde846a6b2182dad01 (patch) | |
| tree | e94a81a8da6c304891abe9b054e8c9009ca62c76 /drivers/tty/serial/sh-sci.c | |
| parent | 658daa95b6aec9c06e1d8c4b99d89b186e4b2e72 (diff) | |
serial: sh-sci: Do not resubmit DMA descriptors
Resubmission of DMA descriptors is explicitly forbidden by the DMA
engine API.
Hence pass DMA_CTRL_ACK to dmaengine_prep_slave_sg(), and prepare a new
DMA descriptor instead of reusing the old one.
Remove sci_port.desc_rx[], as there's no longer a need to access the
active descriptor.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/sh-sci.c')
| -rw-r--r-- | drivers/tty/serial/sh-sci.c | 30 |
1 files changed, 18 insertions, 12 deletions
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index 9c2bc0f23d3a..e318f002da39 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -104,7 +104,6 @@ struct sci_port { struct dma_chan *chan_rx; #ifdef CONFIG_SERIAL_SH_SCI_DMA - struct dma_async_tx_descriptor *desc_rx[2]; dma_cookie_t cookie_tx; dma_cookie_t cookie_rx[2]; dma_cookie_t active_rx; @@ -1397,11 +1396,11 @@ static void sci_submit_rx(struct sci_port *s) struct dma_async_tx_descriptor *desc; desc = dmaengine_prep_slave_sg(chan, - sg, 1, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT); + sg, 1, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc) goto fail; - s->desc_rx[i] = desc; desc->callback = sci_dma_rx_complete; desc->callback_param = s; s->cookie_rx[i] = dmaengine_submit(desc); @@ -1420,10 +1419,8 @@ static void sci_submit_rx(struct sci_port *s) fail: if (i) dmaengine_terminate_all(chan); - for (i = 0; i < 2; i++) { - s->desc_rx[i] = NULL; + for (i = 0; i < 2; i++) s->cookie_rx[i] = -EINVAL; - } s->active_rx = -EINVAL; dev_warn(s->port.dev, "Failed to re-start Rx DMA, using PIO\n"); sci_rx_dma_release(s, true); @@ -1447,7 +1444,6 @@ static void work_fn_rx(struct work_struct *work) s->active_rx); return; } - desc = s->desc_rx[new]; status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state); if (status != DMA_COMPLETE) { @@ -1474,17 +1470,27 @@ static void work_fn_rx(struct work_struct *work) return; } + desc = dmaengine_prep_slave_sg(s->chan_rx, &s->sg_rx[new], 1, + DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc) + goto fail; + + desc->callback = sci_dma_rx_complete; + desc->callback_param = s; s->cookie_rx[new] = dmaengine_submit(desc); - if (dma_submit_error(s->cookie_rx[new])) { - dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n"); - sci_rx_dma_release(s, true); - return; - } + if (dma_submit_error(s->cookie_rx[new])) + goto fail; s->active_rx = s->cookie_rx[!new]; dev_dbg(port->dev, "%s: cookie %d #%d, new active cookie %d\n", __func__, s->cookie_rx[new], new, s->active_rx); + return; + +fail: + dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n"); + sci_rx_dma_release(s, true); } static void work_fn_tx(struct work_struct *work) |