DMAENGINE: COH 901 318 descriptor pool refactoring

This centralize some spread-out initialization of descriptors into
one function and cleans up the error paths.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/arch/arm/mach-u300/include/mach/coh901318.h b/arch/arm/mach-u300/include/mach/coh901318.h
index f4cfee9..b8155b4 100644 (file)
--- a/arch/arm/mach-u300/include/mach/coh901318.h
+++ b/arch/arm/mach-u300/include/mach/coh901318.h
@@ -53,7 +53,7 @@ struct coh901318_params {
  * struct coh_dma_channel - dma channel base
  * @name: ascii name of dma channel
  * @number: channel id number
- * @desc_nbr_max: number of preallocated descriptortors
+ * @desc_nbr_max: number of preallocated descriptors
  * @priority_high: prio of channel, 0 low otherwise high.
  * @param: configuration parameters
  * @dev_addr: physical address of periphal connected to channel

diff --git a/drivers/dma/coh901318.c b/drivers/dma/coh901318.c
index f1bf4f7..12a7a15 100644 (file)
--- a/drivers/dma/coh901318.c
+++ b/drivers/dma/coh901318.c
@@ -335,16 +335,22 @@ coh901318_desc_get(struct coh901318_chan *cohc)
                 * TODO: alloc a pile of descs instead of just one,
                 * avoid many small allocations.
                 */
-               desc = kmalloc(sizeof(struct coh901318_desc), GFP_NOWAIT);
+               desc = kzalloc(sizeof(struct coh901318_desc), GFP_NOWAIT);
                if (desc == NULL)
                        goto out;
                INIT_LIST_HEAD(&desc->node);
+               dma_async_tx_descriptor_init(&desc->desc, &cohc->chan);
        } else {
                /* Reuse an old desc. */
                desc = list_first_entry(&cohc->free,
                                        struct coh901318_desc,
                                        node);
                list_del(&desc->node);
+               /* Initialize it a bit so it's not insane */
+               desc->sg = NULL;
+               desc->sg_len = 0;
+               desc->desc.callback = NULL;
+               desc->desc.callback_param = NULL;
        }
 
  out:
@@ -885,6 +891,7 @@ coh901318_prep_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
        struct coh901318_chan *cohc = to_coh901318_chan(chan);
        int lli_len;
        u32 ctrl_last = cohc_chan_param(cohc)->ctrl_lli_last;
+       int ret;
 
        spin_lock_irqsave(&cohc->lock, flg);
 
@@ -905,22 +912,19 @@ coh901318_prep_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
        if (data == NULL)
                goto err;
 
-       cohd = coh901318_desc_get(cohc);
-       cohd->sg = NULL;
-       cohd->sg_len = 0;
-       cohd->data = data;
-
-       cohd->pending_irqs =
-               coh901318_lli_fill_memcpy(
-                               &cohc->base->pool, data, src, size, dest,
-                               cohc_chan_param(cohc)->ctrl_lli_chained,
-                               ctrl_last);
-       cohd->flags = flags;
+       ret = coh901318_lli_fill_memcpy(
+               &cohc->base->pool, data, src, size, dest,
+               cohc_chan_param(cohc)->ctrl_lli_chained,
+               ctrl_last);
+       if (ret)
+               goto err;
 
        COH_DBG(coh901318_list_print(cohc, data));
 
-       dma_async_tx_descriptor_init(&cohd->desc, chan);
-
+       /* Pick a descriptor to handle this transfer */
+       cohd = coh901318_desc_get(cohc);
+       cohd->data = data;
+       cohd->flags = flags;
        cohd->desc.tx_submit = coh901318_tx_submit;
 
        spin_unlock_irqrestore(&cohc->lock, flg);
@@ -962,11 +966,6 @@ coh901318_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
                /* Trigger interrupt after last lli */
                ctrl_last |= COH901318_CX_CTRL_TC_IRQ_ENABLE;
 
-       cohd = coh901318_desc_get(cohc);
-       cohd->sg = NULL;
-       cohd->sg_len = 0;
-       cohd->dir = direction;
-
        if (direction == DMA_TO_DEVICE) {
                u32 tx_flags = COH901318_CX_CTRL_PRDD_SOURCE |
                        COH901318_CX_CTRL_SRC_ADDR_INC_ENABLE;
@@ -984,11 +983,6 @@ coh901318_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
        } else
                goto err_direction;
 
-       dma_async_tx_descriptor_init(&cohd->desc, chan);
-
-       cohd->desc.tx_submit = coh901318_tx_submit;
-
-
        /* The dma only supports transmitting packages up to
         * MAX_DMA_PACKET_SIZE. Calculate to total number of
         * dma elemts required to send the entire sg list
@@ -1023,19 +1017,21 @@ coh901318_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
                                      ctrl,
                                      ctrl_last,
                                      direction, COH901318_CX_CTRL_TC_IRQ_ENABLE);
-       cohd->data = data;
-
-       cohd->flags = flags;
 
        COH_DBG(coh901318_list_print(cohc, data));
 
+       /* Pick a descriptor to handle this transfer */
+       cohd = coh901318_desc_get(cohc);
+       cohd->dir = direction;
+       cohd->flags = flags;
+       cohd->desc.tx_submit = coh901318_tx_submit;
+       cohd->data = data;
+
        spin_unlock_irqrestore(&cohc->lock, flg);
 
        return &cohd->desc;
  err_dma_alloc:
  err_direction:
-       coh901318_desc_remove(cohd);
-       coh901318_desc_free(cohc, cohd);
        spin_unlock_irqrestore(&cohc->lock, flg);
  out:
        return NULL;