Commit 836c3ce2 authored by Peter Ujfalusi's avatar Peter Ujfalusi Committed by Vinod Koul
Browse files

dmaengine: omap-dma: Fix dynamic lch_map allocation 



The original patch did not done what it was supposed to be doing and even
worst it broke legacy boot (OMAP1).

The lch_map size should be the number of available logical channels in sDMA
and the od->dma_requests should store the number of available DMA request
lines usable in sDMA.

In legacy mode we do not have a way to get the DMA request count, in that
case we use OMAP_SDMA_REQUESTS (127), despite the fact that OMAP1510 have
only 31 DMA request line.

Fixes: 2d1a9a94 ("dmaengine: omap-dma: Dynamically allocate memory for lch_map")
Reported-by: default avatarAaro Koskinen <aaro.koskinen@iki.fi>
Cc: stable@vger.kernel.org   # v4.9
Signed-off-by: default avatarPeter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: default avatarAaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: default avatarVinod Koul <vinod.koul@intel.com>
parent 75bdc7f3

drivers/dma/omap-dma.c

+21 −9
Original line number Diff line number Diff line
@@ -1452,6 +1452,7 @@ static int omap_dma_probe(struct platform_device *pdev) 
	struct omap_dmadev *od;

	struct resource *res;

	int rc, i, irq;

	u32 lch_count;



	od = devm_kzalloc(&pdev->dev, sizeof(*od), GFP_KERNEL);

	if (!od)
@@ -1494,20 +1495,31 @@ static int omap_dma_probe(struct platform_device *pdev) 
	spin_lock_init(&od->lock);

	spin_lock_init(&od->irq_lock);



	if (!pdev->dev.of_node) {

		od->dma_requests = od->plat->dma_attr->lch_count;

		if (unlikely(!od->dma_requests))

	/* Number of DMA requests */

	od->dma_requests = OMAP_SDMA_REQUESTS;

	} else if (of_property_read_u32(pdev->dev.of_node, "dma-requests",

	if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node,

						      "dma-requests",

						      &od->dma_requests)) {

		dev_info(&pdev->dev,

			 "Missing dma-requests property, using %u.\n",

			 OMAP_SDMA_REQUESTS);

		od->dma_requests = OMAP_SDMA_REQUESTS;

	}



	od->lch_map = devm_kcalloc(&pdev->dev, od->dma_requests,

				   sizeof(*od->lch_map), GFP_KERNEL);

	/* Number of available logical channels */

	if (!pdev->dev.of_node) {

		lch_count = od->plat->dma_attr->lch_count;

		if (unlikely(!lch_count))

			lch_count = OMAP_SDMA_CHANNELS;

	} else if (of_property_read_u32(pdev->dev.of_node, "dma-channels",

					&lch_count)) {

		dev_info(&pdev->dev,

			 "Missing dma-channels property, using %u.\n",

			 OMAP_SDMA_CHANNELS);

		lch_count = OMAP_SDMA_CHANNELS;

	}



	od->lch_map = devm_kcalloc(&pdev->dev, lch_count, sizeof(*od->lch_map),

				   GFP_KERNEL);

	if (!od->lch_map)

		return -ENOMEM;

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