diff options
| author | Atsushi Nemoto <anemo@mba.ocn.ne.jp> | 2009-03-06 12:07:14 +0100 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2009-03-26 17:48:09 +0100 |
| commit | 0f571515c332e00b3515dbe0859ceaa30ab66e00 (patch) | |
| tree | 6d67c555714264dda749e387cee6738f770abc5d | |
| parent | dmatest: add dma interrupts and callbacks (diff) | |
| download | linux-0f571515c332e00b3515dbe0859ceaa30ab66e00.tar.xz linux-0f571515c332e00b3515dbe0859ceaa30ab66e00.zip | |
dmaengine: Add privatecnt to revert DMA_PRIVATE property
Currently dma_request_channel() set DMA_PRIVATE capability but never
clear it. So if a public channel was once grabbed by
dma_request_channel(), the device stay PRIVATE forever. Add
privatecnt member to dma_device to correctly revert it.
[lg@denx.de: fix bad usage of 'chan' in dma_async_device_register]
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| -rw-r--r-- | drivers/dma/dmaengine.c | 8 | ||||
| -rw-r--r-- | include/linux/dmaengine.h | 9 |
2 files changed, 17 insertions, 0 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index a41d1ea10fa3..92438e9dacc3 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -507,6 +507,7 @@ struct dma_chan *__dma_request_channel(dma_cap_mask_t *mask, dma_filter_fn fn, v * published in the general-purpose allocator */ dma_cap_set(DMA_PRIVATE, device->cap_mask); + device->privatecnt++; err = dma_chan_get(chan); if (err == -ENODEV) { @@ -518,6 +519,8 @@ struct dma_chan *__dma_request_channel(dma_cap_mask_t *mask, dma_filter_fn fn, v dma_chan_name(chan), err); else break; + if (--device->privatecnt == 0) + dma_cap_clear(DMA_PRIVATE, device->cap_mask); chan->private = NULL; chan = NULL; } @@ -537,6 +540,9 @@ void dma_release_channel(struct dma_chan *chan) WARN_ONCE(chan->client_count != 1, "chan reference count %d != 1\n", chan->client_count); dma_chan_put(chan); + /* drop PRIVATE cap enabled by __dma_request_channel() */ + if (--chan->device->privatecnt == 0) + dma_cap_clear(DMA_PRIVATE, chan->device->cap_mask); chan->private = NULL; mutex_unlock(&dma_list_mutex); } @@ -719,6 +725,8 @@ int dma_async_device_register(struct dma_device *device) } } list_add_tail_rcu(&device->global_node, &dma_device_list); + if (dma_has_cap(DMA_PRIVATE, device->cap_mask)) + device->privatecnt++; /* Always private */ dma_channel_rebalance(); mutex_unlock(&dma_list_mutex); diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 2afc2c95e42d..2e2aa3df170c 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -202,6 +202,7 @@ struct dma_async_tx_descriptor { /** * struct dma_device - info on the entity supplying DMA services * @chancnt: how many DMA channels are supported + * @privatecnt: how many DMA channels are requested by dma_request_channel * @channels: the list of struct dma_chan * @global_node: list_head for global dma_device_list * @cap_mask: one or more dma_capability flags @@ -224,6 +225,7 @@ struct dma_async_tx_descriptor { struct dma_device { unsigned int chancnt; + unsigned int privatecnt; struct list_head channels; struct list_head global_node; dma_cap_mask_t cap_mask; @@ -352,6 +354,13 @@ __dma_cap_set(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp) set_bit(tx_type, dstp->bits); } +#define dma_cap_clear(tx, mask) __dma_cap_clear((tx), &(mask)) +static inline void +__dma_cap_clear(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp) +{ + clear_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) { |