diff options
-rw-r--r-- | drivers/dma/dmaengine.c | 34 | ||||
-rw-r--r-- | include/linux/dmaengine.h | 4 |
2 files changed, 30 insertions, 8 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index 2daf2ee9bebd..51a2f2b1b2de 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -986,6 +986,20 @@ static int __dma_async_device_channel_register(struct dma_device *device, return rc; } +int dma_async_device_channel_register(struct dma_device *device, + struct dma_chan *chan) +{ + int rc; + + rc = __dma_async_device_channel_register(device, chan, -1); + if (rc < 0) + return rc; + + dma_channel_rebalance(); + return 0; +} +EXPORT_SYMBOL_GPL(dma_async_device_channel_register); + static void __dma_async_device_channel_unregister(struct dma_device *device, struct dma_chan *chan) { @@ -993,12 +1007,22 @@ static void __dma_async_device_channel_unregister(struct dma_device *device, "%s called while %d clients hold a reference\n", __func__, chan->client_count); mutex_lock(&dma_list_mutex); + list_del(&chan->device_node); + device->chancnt--; chan->dev->chan = NULL; mutex_unlock(&dma_list_mutex); device_unregister(&chan->dev->device); free_percpu(chan->local); } +void dma_async_device_channel_unregister(struct dma_device *device, + struct dma_chan *chan) +{ + __dma_async_device_channel_unregister(device, chan); + dma_channel_rebalance(); +} +EXPORT_SYMBOL_GPL(dma_async_device_channel_unregister); + /** * dma_async_device_register - registers DMA devices found * @device: &dma_device @@ -1121,12 +1145,6 @@ int dma_async_device_register(struct dma_device *device) goto err_out; } - if (!device->chancnt) { - dev_err(device->dev, "%s: device has no channels!\n", __func__); - rc = -ENODEV; - goto err_out; - } - mutex_lock(&dma_list_mutex); /* take references on public channels */ if (dmaengine_ref_count && !dma_has_cap(DMA_PRIVATE, device->cap_mask)) @@ -1181,9 +1199,9 @@ EXPORT_SYMBOL(dma_async_device_register); */ void dma_async_device_unregister(struct dma_device *device) { - struct dma_chan *chan; + struct dma_chan *chan, *n; - list_for_each_entry(chan, &device->channels, device_node) + list_for_each_entry_safe(chan, n, &device->channels, device_node) __dma_async_device_channel_unregister(device, chan); mutex_lock(&dma_list_mutex); diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 9cc0e70e7c35..f52f274773ed 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -1521,6 +1521,10 @@ static inline int dmaengine_desc_free(struct dma_async_tx_descriptor *desc) int dma_async_device_register(struct dma_device *device); int dmaenginem_async_device_register(struct dma_device *device); void dma_async_device_unregister(struct dma_device *device); +int dma_async_device_channel_register(struct dma_device *device, + struct dma_chan *chan); +void dma_async_device_channel_unregister(struct dma_device *device, + struct dma_chan *chan); void dma_run_dependencies(struct dma_async_tx_descriptor *tx); #define dma_request_channel(mask, x, y) \ __dma_request_channel(&(mask), x, y, NULL) |