diff options
| -rw-r--r-- | drivers/dma/amba-pl08x.c | 11 | ||||
| -rw-r--r-- | include/linux/amba/pl08x.h | 3 |
2 files changed, 14 insertions, 0 deletions
diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c index 650e2bbc7aad..bf6f7d02c9f6 100644 --- a/drivers/dma/amba-pl08x.c +++ b/drivers/dma/amba-pl08x.c @@ -959,6 +959,7 @@ static int prep_phy_channel(struct pl08x_dma_chan *plchan, ch->signal, plchan->name); + plchan->phychan_hold++; plchan->phychan = ch; return 0; @@ -998,6 +999,8 @@ static dma_cookie_t pl08x_tx_submit(struct dma_async_tx_descriptor *tx) /* Do this memcpy whenever there is a channel ready */ plchan->state = PL08X_CHAN_WAITING; plchan->waiting = txd; + } else { + plchan->phychan_hold--; } /* This unlock follows the lock in the prep() function */ @@ -1585,6 +1588,7 @@ static void pl08x_tasklet(unsigned long data) */ plchan->lc = txd->tx.cookie; } + /* * If a new descriptor is queued, set it up * plchan->at is NULL here @@ -1598,6 +1602,12 @@ static void pl08x_tasklet(unsigned long data) list_del(&next->node); pl08x_start_txd(plchan, next); + } else if (plchan->phychan_hold) { + /* + * This channel is still in use - we have a new txd being + * prepared and will soon be queued. Don't give up the + * physical channel. + */ } else { struct pl08x_dma_chan *waiting = NULL; @@ -1625,6 +1635,7 @@ static void pl08x_tasklet(unsigned long data) ret = prep_phy_channel(waiting, waiting->waiting); BUG_ON(ret); + waiting->phychan_hold--; waiting->state = PL08X_CHAN_RUNNING; waiting->waiting = NULL; pl08x_issue_pending(&waiting->chan); diff --git a/include/linux/amba/pl08x.h b/include/linux/amba/pl08x.h index 08a9024e2d2f..95b76ea1829f 100644 --- a/include/linux/amba/pl08x.h +++ b/include/linux/amba/pl08x.h @@ -151,6 +151,8 @@ enum pl08x_dma_chan_state { * struct pl08x_dma_chan - this structure wraps a DMA ENGINE channel * @chan: wrappped abstract channel * @phychan: the physical channel utilized by this channel, if there is one + * @phychan_hold: if non-zero, hold on to the physical channel even if we + * have no pending entries * @tasklet: tasklet scheduled by the IRQ to handle actual work etc * @name: name of channel * @cd: channel platform data @@ -173,6 +175,7 @@ enum pl08x_dma_chan_state { struct pl08x_dma_chan { struct dma_chan chan; struct pl08x_phy_chan *phychan; + int phychan_hold; struct tasklet_struct tasklet; char *name; struct pl08x_channel_data *cd; |