Commit bad83565 authored by Peter Ujfalusi's avatar Peter Ujfalusi Committed by Vinod Koul
Browse files

dmaengine: Cleanups for the slave <-> channel symlink support 



No need to use goto to jump over the
return chan ? chan : ERR_PTR(-EPROBE_DEFER);
We can just revert the check and return right there.

Do not fail the channel request if the chan->name allocation fails, but
print a warning about it.

Change the dev_err to dev_warn if sysfs_create_link() fails as it is not
fatal.

Only attempt to remove the DMA_SLAVE_NAME symlink if it is created - or it
was attempted to be created.

Signed-off-by: default avatarPeter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: default avatarGeert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200131093859.3311-2-peter.ujfalusi@ti.com


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent 5429b51f

drivers/dma/dmaengine.c

+9 −9
Original line number Diff line number Diff line
@@ -756,22 +756,21 @@ struct dma_chan *dma_request_chan(struct device *dev, const char *name) 
	}

	mutex_unlock(&dma_list_mutex);



	if (!IS_ERR_OR_NULL(chan))

		goto found;



	if (IS_ERR_OR_NULL(chan))

		return chan ? chan : ERR_PTR(-EPROBE_DEFER);



found:

	chan->slave = dev;

	chan->name = kasprintf(GFP_KERNEL, "dma:%s", name);

	if (!chan->name)

		return ERR_PTR(-ENOMEM);

		return chan;

	chan->slave = dev;



	if (sysfs_create_link(&chan->dev->device.kobj, &dev->kobj,

			      DMA_SLAVE_NAME))

		dev_err(dev, "Cannot create DMA %s symlink\n", DMA_SLAVE_NAME);

		dev_warn(dev, "Cannot create DMA %s symlink\n", DMA_SLAVE_NAME);

	if (sysfs_create_link(&dev->kobj, &chan->dev->device.kobj, chan->name))

		dev_err(dev, "Cannot create DMA %s symlink\n", chan->name);

		dev_warn(dev, "Cannot create DMA %s symlink\n", chan->name);



	return chan;

}

EXPORT_SYMBOL_GPL(dma_request_chan);
@@ -830,13 +829,14 @@ void dma_release_channel(struct dma_chan *chan) 
	/* drop PRIVATE cap enabled by __dma_request_channel() */

	if (--chan->device->privatecnt == 0)

		dma_cap_clear(DMA_PRIVATE, chan->device->cap_mask);



	if (chan->slave) {

		sysfs_remove_link(&chan->dev->device.kobj, DMA_SLAVE_NAME);

		sysfs_remove_link(&chan->slave->kobj, chan->name);

		kfree(chan->name);

		chan->name = NULL;

		chan->slave = NULL;

	}

	sysfs_remove_link(&chan->dev->device.kobj, DMA_SLAVE_NAME);

	mutex_unlock(&dma_list_mutex);

}

EXPORT_SYMBOL_GPL(dma_release_channel);

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