On 14-05-19, 11:09, Peter Ujfalusi wrote:
> When a DMA client driver decides that it is not providing callback for
> completion of a transfer (and/or does not set the DMA_PREP_INTERRUPT) but
> it will poll the status of the transfer (in case of short memcpy for
> example) we will not get interrupt for the completion of the transfer and
> will not mark the transaction as done.
>
> Check the event registers (ER and EER) and if the channel is inactive then
> return wioth DMA_COMPLETE to let the client know that the transfer is
^^^^^
Typo
> completed.
>
> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
> ---
> drivers/dma/ti/edma.c | 23 ++++++++++++++++++++---
> 1 file changed, 20 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/dma/ti/edma.c b/drivers/dma/ti/edma.c
> index ceabdea40ae0..7501445af069 100644
> --- a/drivers/dma/ti/edma.c
> +++ b/drivers/dma/ti/edma.c
> @@ -1211,8 +1211,9 @@ static struct dma_async_tx_descriptor *edma_prep_dma_memcpy(
>
> edesc->pset[0].param.opt |= ITCCHEN;
> if (nslots == 1) {
> - /* Enable transfer complete interrupt */
> - edesc->pset[0].param.opt |= TCINTEN;
> + /* Enable transfer complete interrupt if requested */
> + if (tx_flags & DMA_PREP_INTERRUPT)
> + edesc->pset[0].param.opt |= TCINTEN;
> } else {
> /* Enable transfer complete chaining for the first slot */
> edesc->pset[0].param.opt |= TCCHEN;
> @@ -1239,7 +1240,9 @@ static struct dma_async_tx_descriptor *edma_prep_dma_memcpy(
> }
>
> edesc->pset[1].param.opt |= ITCCHEN;
> - edesc->pset[1].param.opt |= TCINTEN;
> + /* Enable transfer complete interrupt if requested */
> + if (tx_flags & DMA_PREP_INTERRUPT)
> + edesc->pset[1].param.opt |= TCINTEN;
> }
>
> return vchan_tx_prep(&echan->vchan, &edesc->vdesc, tx_flags);
> @@ -1801,6 +1804,20 @@ static enum dma_status edma_tx_status(struct dma_chan *chan,
> unsigned long flags;
>
> ret = dma_cookie_status(chan, cookie, txstate);
> +
> + if (ret != DMA_COMPLETE && echan->edesc && !echan->edesc->cyclic) {
> + struct edma_cc *ecc = echan->ecc;
> + int channel = EDMA_CHAN_SLOT(echan->ch_num);
> + int j = (channel >> 5);
> + unsigned int mask = BIT(channel & 0x1f);
GENMASK or define a macro instead of a magic number?
> + unsigned int sh_er = edma_shadow0_read_array(ecc, SH_ER, j);
> + unsigned int sh_eer = edma_shadow0_read_array(ecc, SH_EER, j);
> +
> + /* The channel is no longer active */
> + if (!(sh_er & mask) && !(sh_eer & mask))
> + ret = DMA_COMPLETE;
> + }
> +
> if (ret == DMA_COMPLETE || !txstate)
> return ret;
>
> --
> Peter
>
> Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
> Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
--
~Vinod
