DMA: PL330: Infer transfer direction from transfer request instead of platform data
authorThomas Abraham <thomas.abraham@linaro.org>
Mon, 24 Oct 2011 09:43:11 +0000 (11:43 +0200)
committerKukjin Kim <kgene.kim@samsung.com>
Fri, 23 Dec 2011 01:07:03 +0000 (10:07 +0900)
The transfer direction for a channel can be inferred from the transfer
request and the need for specifying transfer direction in platfrom data
can be eliminated. So the structure definition 'struct dma_pl330_peri'
is no longer required.

The channel's private data is set to point to a channel id specified in
the platform data (instead of an instance of type 'struct dma_pl330_peri').
The filter function is correspondingly modified to match the channel id.

With the 'struct dma_pl330_peri' removed from platform data, the dma
controller transfer capabilities cannot be inferred any more. Hence,
the dma controller capabilities is specified using platform data.

Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
Acked-by: Boojin Kim <boojin.kim@samsung.com>
Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
drivers/dma/pl330.c
include/linux/amba/pl330.h

index 0c434dc..317aaea 100644 (file)
@@ -272,13 +272,13 @@ static void dma_pl330_rqcb(void *token, enum pl330_op_err err)
 
 bool pl330_filter(struct dma_chan *chan, void *param)
 {
-       struct dma_pl330_peri *peri;
+       u8 *peri_id;
 
        if (chan->device->dev->driver != &pl330_driver.drv)
                return false;
 
-       peri = chan->private;
-       return peri->peri_id == (unsigned)param;
+       peri_id = chan->private;
+       return *peri_id == (unsigned)param;
 }
 EXPORT_SYMBOL(pl330_filter);
 
@@ -512,7 +512,7 @@ pluck_desc(struct dma_pl330_dmac *pdmac)
 static struct dma_pl330_desc *pl330_get_desc(struct dma_pl330_chan *pch)
 {
        struct dma_pl330_dmac *pdmac = pch->dmac;
-       struct dma_pl330_peri *peri = pch->chan.private;
+       u8 *peri_id = pch->chan.private;
        struct dma_pl330_desc *desc;
 
        /* Pluck one desc from the pool of DMAC */
@@ -537,13 +537,7 @@ static struct dma_pl330_desc *pl330_get_desc(struct dma_pl330_chan *pch)
        desc->txd.cookie = 0;
        async_tx_ack(&desc->txd);
 
-       if (peri) {
-               desc->req.rqtype = peri->rqtype;
-               desc->req.peri = pch->chan.chan_id;
-       } else {
-               desc->req.rqtype = MEMTOMEM;
-               desc->req.peri = 0;
-       }
+       desc->req.peri = peri_id ? pch->chan.chan_id : 0;
 
        dma_async_tx_descriptor_init(&desc->txd, &pch->chan);
 
@@ -630,12 +624,14 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic(
        case DMA_TO_DEVICE:
                desc->rqcfg.src_inc = 1;
                desc->rqcfg.dst_inc = 0;
+               desc->req.rqtype = MEMTODEV;
                src = dma_addr;
                dst = pch->fifo_addr;
                break;
        case DMA_FROM_DEVICE:
                desc->rqcfg.src_inc = 0;
                desc->rqcfg.dst_inc = 1;
+               desc->req.rqtype = DEVTOMEM;
                src = pch->fifo_addr;
                dst = dma_addr;
                break;
@@ -661,16 +657,12 @@ pl330_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst,
 {
        struct dma_pl330_desc *desc;
        struct dma_pl330_chan *pch = to_pchan(chan);
-       struct dma_pl330_peri *peri = chan->private;
        struct pl330_info *pi;
        int burst;
 
        if (unlikely(!pch || !len))
                return NULL;
 
-       if (peri && peri->rqtype != MEMTOMEM)
-               return NULL;
-
        pi = &pch->dmac->pif;
 
        desc = __pl330_prep_dma_memcpy(pch, dst, src, len);
@@ -679,6 +671,7 @@ pl330_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst,
 
        desc->rqcfg.src_inc = 1;
        desc->rqcfg.dst_inc = 1;
+       desc->req.rqtype = MEMTOMEM;
 
        /* Select max possible burst size */
        burst = pi->pcfg.data_bus_width / 8;
@@ -707,24 +700,13 @@ pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 {
        struct dma_pl330_desc *first, *desc = NULL;
        struct dma_pl330_chan *pch = to_pchan(chan);
-       struct dma_pl330_peri *peri = chan->private;
        struct scatterlist *sg;
        unsigned long flags;
        int i;
        dma_addr_t addr;
 
-       if (unlikely(!pch || !sgl || !sg_len || !peri))
-               return NULL;
-
-       /* Make sure the direction is consistent */
-       if ((direction == DMA_TO_DEVICE &&
-                               peri->rqtype != MEMTODEV) ||
-                       (direction == DMA_FROM_DEVICE &&
-                               peri->rqtype != DEVTOMEM)) {
-               dev_err(pch->dmac->pif.dev, "%s:%d Invalid Direction\n",
-                               __func__, __LINE__);
+       if (unlikely(!pch || !sgl || !sg_len))
                return NULL;
-       }
 
        addr = pch->fifo_addr;
 
@@ -765,11 +747,13 @@ pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
                if (direction == DMA_TO_DEVICE) {
                        desc->rqcfg.src_inc = 1;
                        desc->rqcfg.dst_inc = 0;
+                       desc->req.rqtype = MEMTODEV;
                        fill_px(&desc->px,
                                addr, sg_dma_address(sg), sg_dma_len(sg));
                } else {
                        desc->rqcfg.src_inc = 0;
                        desc->rqcfg.dst_inc = 1;
+                       desc->req.rqtype = DEVTOMEM;
                        fill_px(&desc->px,
                                sg_dma_address(sg), addr, sg_dma_len(sg));
                }
@@ -876,28 +860,7 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
 
        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);
-                               dma_cap_set(DMA_CYCLIC, 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);
-                       pch->chan.private = NULL;
-               }
-
+               pch->chan.private = pdat ? &pdat->peri_id[i] : NULL;
                INIT_LIST_HEAD(&pch->work_list);
                spin_lock_init(&pch->lock);
                pch->pl330_chid = NULL;
@@ -909,6 +872,10 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
        }
 
        pd->dev = &adev->dev;
+       if (pdat)
+               pd->cap_mask = pdat->cap_mask;
+       else
+               dma_cap_set(DMA_MEMCPY, pd->cap_mask);
 
        pd->device_alloc_chan_resources = pl330_alloc_chan_resources;
        pd->device_free_chan_resources = pl330_free_chan_resources;
index 6db72da..12e023c 100644 (file)
 #include <linux/dmaengine.h>
 #include <asm/hardware/pl330.h>
 
-struct dma_pl330_peri {
-       /*
-        * Peri_Req i/f of the DMAC that is
-        * peripheral could be reached from.
-        */
-       u8 peri_id; /* specific dma id */
-       enum pl330_reqtype rqtype;
-};
-
 struct dma_pl330_platdata {
        /*
         * Number of valid peripherals connected to DMAC.
@@ -34,7 +25,9 @@ struct dma_pl330_platdata {
         */
        u8 nr_valid_peri;
        /* Array of valid peripherals */
-       struct dma_pl330_peri *peri;
+       u8 *peri_id;
+       /* Operational capabilities */
+       dma_cap_mask_t cap_mask;
        /* Bytes to allocate for MC buffer */
        unsigned mcbuf_sz;
 };