[PATCH V4 03-1/13] DMA: PL330: Support DMA_SLAVE_CONFIG command

Jassi Brar jassisinghbrar at gmail.com
Wed Jul 20 15:17:49 EDT 2011


On Wed, Jul 20, 2011 at 4:16 PM, Boojin Kim <boojin.kim at samsung.com> wrote:
> Signed-off-by: Boojin Kim <boojin.kim at samsung.com>
> Signed-off-by: Kukjin Kim <kgene.kim at samsung.com>
> ---
>  drivers/dma/pl330.c |   53 +++++++++++++++++++++++++++++++++++++-------------
>  1 files changed, 39 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
> index 586ab39..880f010 100644
> --- a/drivers/dma/pl330.c
> +++ b/drivers/dma/pl330.c
> @@ -256,25 +256,50 @@ static int pl330_alloc_chan_resources(struct dma_chan *chan)
>  static int pl330_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, unsigned long arg)
>  {
>        struct dma_pl330_chan *pch = to_pchan(chan);
> -       struct dma_pl330_desc *desc;
> +       struct dma_pl330_desc *desc, *_dt;
>        unsigned long flags;
> +       struct dma_pl330_dmac *pdmac = pch->dmac;
> +       struct dma_slave_config *slave_config;
> +       struct dma_pl330_peri *peri;
> +       LIST_HEAD(list);
>
> -       /* Only supports DMA_TERMINATE_ALL */
> -       if (cmd != DMA_TERMINATE_ALL)
> -               return -ENXIO;
> -
> -       spin_lock_irqsave(&pch->lock, flags);
> -
> -       /* FLUSH the PL330 Channel thread */
> -       pl330_chan_ctrl(pch->pl330_chid, PL330_OP_FLUSH);
> +       switch (cmd) {
> +       case DMA_TERMINATE_ALL:
> +               spin_lock_irqsave(&pch->lock, flags);
>
> -       /* Mark all desc done */
> -       list_for_each_entry(desc, &pch->work_list, node)
> -               desc->status = DONE;
> +               /* FLUSH the PL330 Channel thread */
> +               pl330_chan_ctrl(pch->pl330_chid, PL330_OP_FLUSH);
>
> -       spin_unlock_irqrestore(&pch->lock, flags);
> +               /* Mark all desc done */
> +               list_for_each_entry_safe(desc, _dt, &pch->work_list , node) {
> +                       desc->status = DONE;
> +                       pch->completed = desc->txd.cookie;
> +                       list_move_tail(&desc->node, &list);
> +               }
>
> -       pl330_tasklet((unsigned long) pch);
> +               list_splice_tail_init(&list, &pdmac->desc_pool);
> +               spin_unlock_irqrestore(&pch->lock, flags);
> +               break;
> +       case DMA_SLAVE_CONFIG:
Please protect this section too using spin_lock.


> +               if (slave_config->direction == DMA_TO_DEVICE) {
> +                       if (slave_config->dst_addr)
> +                               peri->fifo_addr = slave_config->dst_addr;
> +                       if (slave_config->dst_addr_width)
> +                               peri->burst_sz = __ffs(slave_config->dst_addr_width);
> +               } else if (slave_config->direction == DMA_FROM_DEVICE) {
> +                       if (slave_config->src_addr)
> +                               peri->fifo_addr = slave_config->src_addr;
> +                       if (slave_config->src_addr_width)
> +                               peri->burst_sz = __ffs(slave_config->src_addr_width);
> +               }
PL330 has fixed channels to peripherals.
So FIFO addresses(burst_sz too?) should already be set via platform data.
Client drivers shouldn't bother.

<will review remaining patches soon, gotta go now>



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