diff options
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/dmaengine.c | 135 |
1 files changed, 81 insertions, 54 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index 7550dbdf5488..2daf2ee9bebd 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -926,6 +926,79 @@ static int get_dma_id(struct dma_device *device) return 0; } +static int __dma_async_device_channel_register(struct dma_device *device, + struct dma_chan *chan, + int chan_id) +{ + int rc = 0; + int chancnt = device->chancnt; + atomic_t *idr_ref; + struct dma_chan *tchan; + + tchan = list_first_entry_or_null(&device->channels, + struct dma_chan, device_node); + if (tchan->dev) { + idr_ref = tchan->dev->idr_ref; + } else { + idr_ref = kmalloc(sizeof(*idr_ref), GFP_KERNEL); + if (!idr_ref) + return -ENOMEM; + atomic_set(idr_ref, 0); + } + + chan->local = alloc_percpu(typeof(*chan->local)); + if (!chan->local) + goto err_out; + chan->dev = kzalloc(sizeof(*chan->dev), GFP_KERNEL); + if (!chan->dev) { + free_percpu(chan->local); + chan->local = NULL; + goto err_out; + } + + /* + * When the chan_id is a negative value, we are dynamically adding + * the channel. Otherwise we are static enumerating. + */ + chan->chan_id = chan_id < 0 ? chancnt : chan_id; + chan->dev->device.class = &dma_devclass; + chan->dev->device.parent = device->dev; + chan->dev->chan = chan; + chan->dev->idr_ref = idr_ref; + chan->dev->dev_id = device->dev_id; + atomic_inc(idr_ref); + dev_set_name(&chan->dev->device, "dma%dchan%d", + device->dev_id, chan->chan_id); + + rc = device_register(&chan->dev->device); + if (rc) + goto err_out; + chan->client_count = 0; + device->chancnt = chan->chan_id + 1; + + return 0; + + err_out: + free_percpu(chan->local); + kfree(chan->dev); + if (atomic_dec_return(idr_ref) == 0) + kfree(idr_ref); + return rc; +} + +static void __dma_async_device_channel_unregister(struct dma_device *device, + struct dma_chan *chan) +{ + WARN_ONCE(!device->device_release && chan->client_count, + "%s called while %d clients hold a reference\n", + __func__, chan->client_count); + mutex_lock(&dma_list_mutex); + chan->dev->chan = NULL; + mutex_unlock(&dma_list_mutex); + device_unregister(&chan->dev->device); + free_percpu(chan->local); +} + /** * dma_async_device_register - registers DMA devices found * @device: &dma_device @@ -936,9 +1009,8 @@ static int get_dma_id(struct dma_device *device) */ int dma_async_device_register(struct dma_device *device) { - int chancnt = 0, rc; + int rc, i = 0; struct dma_chan* chan; - atomic_t *idr_ref; if (!device) return -ENODEV; @@ -1038,59 +1110,23 @@ int dma_async_device_register(struct dma_device *device) if (device_has_all_tx_types(device)) dma_cap_set(DMA_ASYNC_TX, device->cap_mask); - idr_ref = kmalloc(sizeof(*idr_ref), GFP_KERNEL); - if (!idr_ref) - return -ENOMEM; rc = get_dma_id(device); - if (rc != 0) { - kfree(idr_ref); + if (rc != 0) return rc; - } - - atomic_set(idr_ref, 0); /* represent channels in sysfs. Probably want devs too */ list_for_each_entry(chan, &device->channels, device_node) { - rc = -ENOMEM; - chan->local = alloc_percpu(typeof(*chan->local)); - if (chan->local == NULL) + rc = __dma_async_device_channel_register(device, chan, i++); + if (rc < 0) goto err_out; - chan->dev = kzalloc(sizeof(*chan->dev), GFP_KERNEL); - if (chan->dev == NULL) { - free_percpu(chan->local); - chan->local = NULL; - goto err_out; - } - - chan->chan_id = chancnt++; - chan->dev->device.class = &dma_devclass; - chan->dev->device.parent = device->dev; - chan->dev->chan = chan; - chan->dev->idr_ref = idr_ref; - chan->dev->dev_id = device->dev_id; - atomic_inc(idr_ref); - dev_set_name(&chan->dev->device, "dma%dchan%d", - device->dev_id, chan->chan_id); - - rc = device_register(&chan->dev->device); - if (rc) { - free_percpu(chan->local); - chan->local = NULL; - kfree(chan->dev); - atomic_dec(idr_ref); - goto err_out; - } - chan->client_count = 0; } - if (!chancnt) { + if (!device->chancnt) { dev_err(device->dev, "%s: device has no channels!\n", __func__); rc = -ENODEV; goto err_out; } - device->chancnt = chancnt; - mutex_lock(&dma_list_mutex); /* take references on public channels */ if (dmaengine_ref_count && !dma_has_cap(DMA_PRIVATE, device->cap_mask)) @@ -1118,9 +1154,8 @@ int dma_async_device_register(struct dma_device *device) err_out: /* if we never registered a channel just release the idr */ - if (atomic_read(idr_ref) == 0) { + if (!device->chancnt) { ida_free(&dma_ida, device->dev_id); - kfree(idr_ref); return rc; } @@ -1148,16 +1183,8 @@ void dma_async_device_unregister(struct dma_device *device) { struct dma_chan *chan; - list_for_each_entry(chan, &device->channels, device_node) { - WARN_ONCE(!device->device_release && chan->client_count, - "%s called while %d clients hold a reference\n", - __func__, chan->client_count); - mutex_lock(&dma_list_mutex); - chan->dev->chan = NULL; - mutex_unlock(&dma_list_mutex); - device_unregister(&chan->dev->device); - free_percpu(chan->local); - } + list_for_each_entry(chan, &device->channels, device_node) + __dma_async_device_channel_unregister(device, chan); mutex_lock(&dma_list_mutex); /* |