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authorBaolin Wang <baolin.wang@linaro.org>2019-05-20 19:32:14 +0800
committerVinod Koul <vkoul@kernel.org>2019-05-27 11:23:52 +0530
commitf5151311c3f37f6edc85b2253ccf6d3e2a4c4c26 (patch)
tree9c9a6c10e2377a16f1eb678605546875f210c8e8 /drivers/dma/dmaengine.c
parentf935d7dc8125e231e3e1620d97b2367b008889f4 (diff)
downloadlinux-f5151311c3f37f6edc85b2253ccf6d3e2a4c4c26.tar.bz2
dmaengine: Add matching device node validation in __dma_request_channel()
When user try to request one DMA channel by __dma_request_channel(), it won't validate if it is the correct DMA device to request, that will lead each DMA engine driver to validate the correct device node in their filter function if it is necessary. Thus we can add the matching device node validation in the DMA engine core, to remove all of device node validation in the drivers. Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma/dmaengine.c')
-rw-r--r--drivers/dma/dmaengine.c10
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 3a11b1092e80..610080c629bb 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -641,11 +641,13 @@ EXPORT_SYMBOL_GPL(dma_get_any_slave_channel);
* @mask: capabilities that the channel must satisfy
* @fn: optional callback to disposition available channels
* @fn_param: opaque parameter to pass to dma_filter_fn
+ * @np: device node to look for DMA channels
*
* Returns pointer to appropriate DMA channel on success or NULL.
*/
struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
- dma_filter_fn fn, void *fn_param)
+ dma_filter_fn fn, void *fn_param,
+ struct device_node *np)
{
struct dma_device *device, *_d;
struct dma_chan *chan = NULL;
@@ -653,6 +655,10 @@ struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
/* Find a channel */
mutex_lock(&dma_list_mutex);
list_for_each_entry_safe(device, _d, &dma_device_list, global_node) {
+ /* Finds a DMA controller with matching device node */
+ if (np && device->dev->of_node && np != device->dev->of_node)
+ continue;
+
chan = find_candidate(device, mask, fn, fn_param);
if (!IS_ERR(chan))
break;
@@ -769,7 +775,7 @@ struct dma_chan *dma_request_chan_by_mask(const dma_cap_mask_t *mask)
if (!mask)
return ERR_PTR(-ENODEV);
- chan = __dma_request_channel(mask, NULL, NULL);
+ chan = __dma_request_channel(mask, NULL, NULL, NULL);
if (!chan) {
mutex_lock(&dma_list_mutex);
if (list_empty(&dma_device_list))