Commit b58b6b5b authored by Russell King - ARM Linux's avatar Russell King - ARM Linux Committed by Dan Williams
Browse files

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: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
Acked-by: default avatarLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent ad0a3ad3

drivers/dma/amba-pl08x.c

+20 −51
Original line number Diff line number Diff line
@@ -927,39 +927,21 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x, 
			__func__, (u32) MAX_NUM_TSFR_LLIS);

		return 0;

	}

	/*

	 * Decide whether this is a loop or a terminated transfer

	 */

	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 {

	llis_va = txd->llis_va;

	/*

		 * On non-circular buffers, the final LLI terminates

		 * the LLI.

	 * 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;

	}



	/* 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->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,
@@ -1643,19 +1613,11 @@ static void pl08x_tasklet(unsigned long data) 
			callback(callback_param);



		/*

		 * Free the descriptor if it's not for a device

		 * using a circular buffer

		 * Free the descriptor

		 */

		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

		 */

	}

	/*

	 * If a new descriptor is queued, set it up

	 * plchan->at is NULL here
@@ -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);