ARM: PL08x: remove circular buffer support

The driver already won't initialize a channel with a circular buffer;
the check in pl08x_prep_channel_resources() sees to that.  Remove
circular buffer support for the time being.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index b721ed2..74b3591 100644 (file)
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -927,39 +927,21 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
                        __func__, (u32) MAX_NUM_TSFR_LLIS);
                return 0;
        }
+
+       llis_va = txd->llis_va;
        /*
-        * Decide whether this is a loop or a terminated transfer
+        * The final LLI terminates the LLI.
         */
-       llis_va = txd->llis_va;
-       llis_bus = (struct lli *) txd->llis_bus;
-
-       if (cd->circular_buffer) {
-               /*
-                * Loop the circular buffer so that the next element
-                * points back to the beginning of the LLI.
-                */
-               llis_va[num_llis - 1].next =
-                       (dma_addr_t)((unsigned int)&(llis_bus[0]));
-       } else {
-               /*
-                * On non-circular buffers, the final LLI terminates
-                * the LLI.
-                */
-               llis_va[num_llis - 1].next = 0;
-               /*
-                * The final LLI element shall also fire an interrupt
-                */
-               llis_va[num_llis - 1].cctl |= PL080_CONTROL_TC_IRQ_EN;
-       }
+       llis_va[num_llis - 1].next = 0;
+       /*
+        * The final LLI element shall also fire an interrupt
+        */
+       llis_va[num_llis - 1].cctl |= PL080_CONTROL_TC_IRQ_EN;
 
        /* Now store the channel register values */
        txd->csrc = llis_va[0].src;
        txd->cdst = llis_va[0].dst;
-       if (num_llis > 1)
-               txd->clli = llis_va[0].next;
-       else
-               txd->clli = 0;
-
+       txd->clli = llis_va[0].next;
        txd->cctl = llis_va[0].cctl;
        /* ccfg will be set at physical channel allocation time */
 
@@ -1334,19 +1316,7 @@ static int pl08x_prep_channel_resources(struct pl08x_dma_chan *plchan,
 
        spin_lock_irqsave(&plchan->lock, plchan->lockflags);
 
-       /*
-        * If this device is not using a circular buffer then
-        * queue this new descriptor for transfer.
-        * The descriptor for a circular buffer continues
-        * to be used until the channel is freed.
-        */
-       if (txd->cd->circular_buffer)
-               dev_err(&pl08x->adev->dev,
-                       "%s attempting to queue a circular buffer\n",
-                       __func__);
-       else
-               list_add_tail(&txd->node,
-                             &plchan->desc_list);
+       list_add_tail(&txd->node, &plchan->desc_list);
 
        /*
         * See if we already have a physical channel allocated,
@@ -1643,18 +1613,10 @@ static void pl08x_tasklet(unsigned long data)
                        callback(callback_param);
 
                /*
-                * Free the descriptor if it's not for a device
-                * using a circular buffer
-                */
-               if (!plchan->at->cd->circular_buffer) {
-                       pl08x_free_txd(pl08x, plchan->at);
-                       plchan->at = NULL;
-               }
-               /*
-                * else descriptor for circular
-                * buffers only freed when
-                * client has disabled dma
+                * Free the descriptor
                 */
+               pl08x_free_txd(pl08x, plchan->at);
+               plchan->at = NULL;
        }
        /*
         * If a new descriptor is queued, set it up
@@ -1799,6 +1761,13 @@ static int pl08x_dma_init_virtual_channels(struct pl08x_driver_data *pl08x,
                                return -ENOMEM;
                        }
                }
+               if (chan->cd->circular_buffer) {
+                       dev_err(&pl08x->adev->dev,
+                               "channel %s: circular buffers not supported\n",
+                               chan->name);
+                       kfree(chan);
+                       continue;
+               }
                dev_info(&pl08x->adev->dev,
                         "initialize virtual channel \"%s\"\n",
                         chan->name);