diff options
| -rw-r--r-- | drivers/dma/dmatest.c | 115 | ||||
| -rw-r--r-- | include/linux/dmaengine.h | 6 |
2 files changed, 49 insertions, 72 deletions
diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c index db4050884713..1d6e48f9cd02 100644 --- a/drivers/dma/dmatest.c +++ b/drivers/dma/dmatest.c @@ -35,7 +35,7 @@ MODULE_PARM_DESC(threads_per_chan, static unsigned int max_channels; module_param(max_channels, uint, S_IRUGO); -MODULE_PARM_DESC(nr_channels, +MODULE_PARM_DESC(max_channels, "Maximum number of channels to use (default: all)"); /* @@ -71,7 +71,7 @@ struct dmatest_chan { /* * These are protected by dma_list_mutex since they're only used by - * the DMA client event callback + * the DMA filter function callback */ static LIST_HEAD(dmatest_channels); static unsigned int nr_channels; @@ -317,21 +317,16 @@ static void dmatest_cleanup_channel(struct dmatest_chan *dtc) kfree(dtc); } -static enum dma_state_client dmatest_add_channel(struct dma_chan *chan) +static int dmatest_add_channel(struct dma_chan *chan) { struct dmatest_chan *dtc; struct dmatest_thread *thread; unsigned int i; - /* Have we already been told about this channel? */ - list_for_each_entry(dtc, &dmatest_channels, node) - if (dtc->chan == chan) - return DMA_DUP; - dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL); if (!dtc) { pr_warning("dmatest: No memory for %s\n", dev_name(&chan->dev)); - return DMA_NAK; + return -ENOMEM; } dtc->chan = chan; @@ -365,81 +360,57 @@ static enum dma_state_client dmatest_add_channel(struct dma_chan *chan) list_add_tail(&dtc->node, &dmatest_channels); nr_channels++; - return DMA_ACK; + return 0; } -static enum dma_state_client dmatest_remove_channel(struct dma_chan *chan) +static enum dma_state_client filter(struct dma_chan *chan, void *param) { - struct dmatest_chan *dtc, *_dtc; - - list_for_each_entry_safe(dtc, _dtc, &dmatest_channels, node) { - if (dtc->chan == chan) { - list_del(&dtc->node); - dmatest_cleanup_channel(dtc); - pr_debug("dmatest: lost channel %s\n", - dev_name(&chan->dev)); - return DMA_ACK; - } - } - - return DMA_DUP; -} - -/* - * Start testing threads as new channels are assigned to us, and kill - * them when the channels go away. - * - * When we unregister the client, all channels are removed so this - * will also take care of cleaning things up when the module is - * unloaded. - */ -static enum dma_state_client -dmatest_event(struct dma_client *client, struct dma_chan *chan, - enum dma_state state) -{ - enum dma_state_client ack = DMA_NAK; - - switch (state) { - case DMA_RESOURCE_AVAILABLE: - if (!dmatest_match_channel(chan) - || !dmatest_match_device(chan->device)) - ack = DMA_DUP; - else if (max_channels && nr_channels >= max_channels) - ack = DMA_NAK; - else - ack = dmatest_add_channel(chan); - break; - - case DMA_RESOURCE_REMOVED: - ack = dmatest_remove_channel(chan); - break; - - default: - pr_info("dmatest: Unhandled event %u (%s)\n", - state, dev_name(&chan->dev)); - break; - } - - return ack; + if (!dmatest_match_channel(chan) || !dmatest_match_device(chan->device)) + return DMA_DUP; + else + return DMA_ACK; } -static struct dma_client dmatest_client = { - .event_callback = dmatest_event, -}; - static int __init dmatest_init(void) { - dma_cap_set(DMA_MEMCPY, dmatest_client.cap_mask); - dma_async_client_register(&dmatest_client); - dma_async_client_chan_request(&dmatest_client); + dma_cap_mask_t mask; + struct dma_chan *chan; + int err = 0; + + dma_cap_zero(mask); + dma_cap_set(DMA_MEMCPY, mask); + for (;;) { + chan = dma_request_channel(mask, filter, NULL); + if (chan) { + err = dmatest_add_channel(chan); + if (err == 0) + continue; + else { + dma_release_channel(chan); + break; /* add_channel failed, punt */ + } + } else + break; /* no more channels available */ + if (max_channels && nr_channels >= max_channels) + break; /* we have all we need */ + } - return 0; + return err; } -module_init(dmatest_init); +/* when compiled-in wait for drivers to load first */ +late_initcall(dmatest_init); static void __exit dmatest_exit(void) { - dma_async_client_unregister(&dmatest_client); + struct dmatest_chan *dtc, *_dtc; + + list_for_each_entry_safe(dtc, _dtc, &dmatest_channels, node) { + list_del(&dtc->node); + dmatest_cleanup_channel(dtc); + pr_debug("dmatest: dropped channel %s\n", + dev_name(&dtc->chan->dev)); + dma_release_channel(dtc->chan); + } } module_exit(dmatest_exit); diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index fe40bc020af6..6f2d070ac7f3 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -400,6 +400,12 @@ __dma_cap_set(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp) set_bit(tx_type, dstp->bits); } +#define dma_cap_zero(mask) __dma_cap_zero(&(mask)) +static inline void __dma_cap_zero(dma_cap_mask_t *dstp) +{ + bitmap_zero(dstp->bits, DMA_TX_TYPE_END); +} + #define dma_has_cap(tx, mask) __dma_has_cap((tx), &(mask)) static inline int __dma_has_cap(enum dma_transaction_type tx_type, dma_cap_mask_t *srcp) |