Re: [PATCH] dmaengine: pl330: make platform data optional

[Vinod Koul]

On Tue, 2011-07-12 at 20:00 -0500, Rob Herring wrote:
> From: Rob Herring <rob.herring@xxxxxxxxxxx>
> 
> The pl330 needs platform data for describing peripheral connections, but
> some platforms may only support memory to memory dma channels. In this
> case, we can probe for how many channels there are and don't need the
> platform data.
> 
> As memcpy requests don't need channel private data to hold peripheral
> info, allow private data to be NULL in this case.
> 
> Signed-off-by: Rob Herring <rob.herring@xxxxxxxxxxx>
> Cc: Jassi Brar <jassi.brar@xxxxxxxxxxx>
> Cc: Vinod Koul <vinod.koul@xxxxxxxxx>
> Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
> ---
>  drivers/dma/pl330.c |   64 ++++++++++++++++++++++++++++----------------------
>  1 files changed, 36 insertions(+), 28 deletions(-)
Applied, Thanks
> 
> diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
> index 7181e43..76fd403 100644
> --- a/drivers/dma/pl330.c
> +++ b/drivers/dma/pl330.c
> @@ -82,7 +82,7 @@ struct dma_pl330_dmac {
>  	spinlock_t pool_lock;
>  
>  	/* Peripheral channels connected to this DMAC */
> -	struct dma_pl330_chan peripherals[0]; /* keep at end */
> +	struct dma_pl330_chan *peripherals; /* keep at end */
>  };
>  
>  struct dma_pl330_desc {
> @@ -451,8 +451,13 @@ static struct dma_pl330_desc *pl330_get_desc(struct dma_pl330_chan *pch)
>  	desc->txd.cookie = 0;
>  	async_tx_ack(&desc->txd);
>  
> -	desc->req.rqtype = peri->rqtype;
> -	desc->req.peri = peri->peri_id;
> +	if (peri) {
> +		desc->req.rqtype = peri->rqtype;
> +		desc->req.peri = peri->peri_id;
> +	} else {
> +		desc->req.rqtype = MEMTOMEM;
> +		desc->req.peri = 0;
> +	}
>  
>  	dma_async_tx_descriptor_init(&desc->txd, &pch->chan);
>  
> @@ -529,10 +534,10 @@ pl330_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst,
>  	struct pl330_info *pi;
>  	int burst;
>  
> -	if (unlikely(!pch || !len || !peri))
> +	if (unlikely(!pch || !len))
>  		return NULL;
>  
> -	if (peri->rqtype != MEMTOMEM)
> +	if (peri && peri->rqtype != MEMTOMEM)
>  		return NULL;
>  
>  	pi = &pch->dmac->pif;
> @@ -577,7 +582,7 @@ pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
>  	int i, burst_size;
>  	dma_addr_t addr;
>  
> -	if (unlikely(!pch || !sgl || !sg_len))
> +	if (unlikely(!pch || !sgl || !sg_len || !peri))
>  		return NULL;
>  
>  	/* Make sure the direction is consistent */
> @@ -666,17 +671,12 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
>  	struct dma_device *pd;
>  	struct resource *res;
>  	int i, ret, irq;
> +	int num_chan;
>  
>  	pdat = adev->dev.platform_data;
>  
> -	if (!pdat || !pdat->nr_valid_peri) {
> -		dev_err(&adev->dev, "platform data missing\n");
> -		return -ENODEV;
> -	}
> -
>  	/* Allocate a new DMAC and its Channels */
> -	pdmac = kzalloc(pdat->nr_valid_peri * sizeof(*pch)
> -				+ sizeof(*pdmac), GFP_KERNEL);
> +	pdmac = kzalloc(sizeof(*pdmac), GFP_KERNEL);
>  	if (!pdmac) {
>  		dev_err(&adev->dev, "unable to allocate mem\n");
>  		return -ENOMEM;
> @@ -685,7 +685,7 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
>  	pi = &pdmac->pif;
>  	pi->dev = &adev->dev;
>  	pi->pl330_data = NULL;
> -	pi->mcbufsz = pdat->mcbuf_sz;
> +	pi->mcbufsz = pdat ? pdat->mcbuf_sz : 0;
>  
>  	res = &adev->res;
>  	request_mem_region(res->start, resource_size(res), "dma-pl330");
> @@ -717,27 +717,35 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
>  	INIT_LIST_HEAD(&pd->channels);
>  
>  	/* Initialize channel parameters */
> -	for (i = 0; i < pdat->nr_valid_peri; i++) {
> -		struct dma_pl330_peri *peri = &pdat->peri[i];
> -		pch = &pdmac->peripherals[i];
> +	num_chan = max(pdat->nr_valid_peri, (u8)pi->pcfg.num_chan);
> +	pdmac->peripherals = kzalloc(num_chan * sizeof(*pch), GFP_KERNEL);
>  
> -		switch (peri->rqtype) {
> -		case MEMTOMEM:
> +	for (i = 0; i < num_chan; i++) {
> +		pch = &pdmac->peripherals[i];
> +		if (pdat) {
> +			struct dma_pl330_peri *peri = &pdat->peri[i];
> +
> +			switch (peri->rqtype) {
> +			case MEMTOMEM:
> +				dma_cap_set(DMA_MEMCPY, pd->cap_mask);
> +				break;
> +			case MEMTODEV:
> +			case DEVTOMEM:
> +				dma_cap_set(DMA_SLAVE, pd->cap_mask);
> +				break;
> +			default:
> +				dev_err(&adev->dev, "DEVTODEV Not Supported\n");
> +				continue;
> +			}
> +			pch->chan.private = peri;
> +		} else {
>  			dma_cap_set(DMA_MEMCPY, pd->cap_mask);
> -			break;
> -		case MEMTODEV:
> -		case DEVTOMEM:
> -			dma_cap_set(DMA_SLAVE, pd->cap_mask);
> -			break;
> -		default:
> -			dev_err(&adev->dev, "DEVTODEV Not Supported\n");
> -			continue;
> +			pch->chan.private = NULL;
>  		}
>  
>  		INIT_LIST_HEAD(&pch->work_list);
>  		spin_lock_init(&pch->lock);
>  		pch->pl330_chid = NULL;
> -		pch->chan.private = peri;
>  		pch->chan.device = pd;
>  		pch->chan.chan_id = i;
>  		pch->dmac = pdmac;

-- 
~Vinod Koul
Intel Corp.

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