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path: root/drivers/dma/dmaengine.c
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Diffstat (limited to 'drivers/dma/dmaengine.c')
-rw-r--r--drivers/dma/dmaengine.c35
1 files changed, 28 insertions, 7 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 97b329e76798..dc003a3a787d 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -169,12 +169,18 @@ static void dma_client_chan_alloc(struct dma_client *client)
enum dma_state_client ack;
/* Find a channel */
- list_for_each_entry(device, &dma_device_list, global_node)
+ list_for_each_entry(device, &dma_device_list, global_node) {
+ /* Does the client require a specific DMA controller? */
+ if (client->slave && client->slave->dma_dev
+ && client->slave->dma_dev != device->dev)
+ continue;
+
list_for_each_entry(chan, &device->channels, device_node) {
if (!dma_chan_satisfies_mask(chan, client->cap_mask))
continue;
- desc = chan->device->device_alloc_chan_resources(chan);
+ desc = chan->device->device_alloc_chan_resources(
+ chan, client);
if (desc >= 0) {
ack = client->event_callback(client,
chan,
@@ -183,12 +189,14 @@ static void dma_client_chan_alloc(struct dma_client *client)
/* we are done once this client rejects
* an available resource
*/
- if (ack == DMA_ACK)
+ if (ack == DMA_ACK) {
dma_chan_get(chan);
- else if (ack == DMA_NAK)
+ chan->client_count++;
+ } else if (ack == DMA_NAK)
return;
}
}
+ }
}
enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie)
@@ -272,8 +280,10 @@ static void dma_clients_notify_removed(struct dma_chan *chan)
/* client was holding resources for this channel so
* free it
*/
- if (ack == DMA_ACK)
+ if (ack == DMA_ACK) {
dma_chan_put(chan);
+ chan->client_count--;
+ }
}
mutex_unlock(&dma_list_mutex);
@@ -285,6 +295,10 @@ static void dma_clients_notify_removed(struct dma_chan *chan)
*/
void dma_async_client_register(struct dma_client *client)
{
+ /* validate client data */
+ BUG_ON(dma_has_cap(DMA_SLAVE, client->cap_mask) &&
+ !client->slave);
+
mutex_lock(&dma_list_mutex);
list_add_tail(&client->global_node, &dma_client_list);
mutex_unlock(&dma_list_mutex);
@@ -313,8 +327,10 @@ void dma_async_client_unregister(struct dma_client *client)
ack = client->event_callback(client, chan,
DMA_RESOURCE_REMOVED);
- if (ack == DMA_ACK)
+ if (ack == DMA_ACK) {
dma_chan_put(chan);
+ chan->client_count--;
+ }
}
list_del(&client->global_node);
@@ -359,6 +375,10 @@ int dma_async_device_register(struct dma_device *device)
!device->device_prep_dma_memset);
BUG_ON(dma_has_cap(DMA_INTERRUPT, device->cap_mask) &&
!device->device_prep_dma_interrupt);
+ BUG_ON(dma_has_cap(DMA_SLAVE, device->cap_mask) &&
+ !device->device_prep_slave_sg);
+ BUG_ON(dma_has_cap(DMA_SLAVE, device->cap_mask) &&
+ !device->device_terminate_all);
BUG_ON(!device->device_alloc_chan_resources);
BUG_ON(!device->device_free_chan_resources);
@@ -378,7 +398,7 @@ int dma_async_device_register(struct dma_device *device)
chan->chan_id = chancnt++;
chan->dev.class = &dma_devclass;
- chan->dev.parent = NULL;
+ chan->dev.parent = device->dev;
snprintf(chan->dev.bus_id, BUS_ID_SIZE, "dma%dchan%d",
device->dev_id, chan->chan_id);
@@ -394,6 +414,7 @@ int dma_async_device_register(struct dma_device *device)
kref_get(&device->refcount);
kref_get(&device->refcount);
kref_init(&chan->refcount);
+ chan->client_count = 0;
chan->slow_ref = 0;
INIT_RCU_HEAD(&chan->rcu);
}