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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-03-25 03:53:42 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-03-25 03:53:42 -0300
commit03dd4cb26d967f9588437b0fc9cc0e8353322bb7 (patch)
treefa581f6dc1c0596391690d1f67eceef3af8246dc /include/linux/dmaengine.h
parentd4e493caf788ef44982e131ff9c786546904d934 (diff)
Linux-libre 4.5-gnu
Diffstat (limited to 'include/linux/dmaengine.h')
-rw-r--r--include/linux/dmaengine.h145
1 files changed, 138 insertions, 7 deletions
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index c47c68e53..16a1cad30 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -607,11 +607,38 @@ enum dmaengine_alignment {
};
/**
+ * struct dma_slave_map - associates slave device and it's slave channel with
+ * parameter to be used by a filter function
+ * @devname: name of the device
+ * @slave: slave channel name
+ * @param: opaque parameter to pass to struct dma_filter.fn
+ */
+struct dma_slave_map {
+ const char *devname;
+ const char *slave;
+ void *param;
+};
+
+/**
+ * struct dma_filter - information for slave device/channel to filter_fn/param
+ * mapping
+ * @fn: filter function callback
+ * @mapcnt: number of slave device/channel in the map
+ * @map: array of channel to filter mapping data
+ */
+struct dma_filter {
+ dma_filter_fn fn;
+ int mapcnt;
+ const struct dma_slave_map *map;
+};
+
+/**
* 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
+ * @filter: information for device/slave to filter function/param mapping
* @cap_mask: one or more dma_capability flags
* @max_xor: maximum number of xor sources, 0 if no capability
* @max_pq: maximum number of PQ sources and PQ-continue capability
@@ -654,11 +681,14 @@ enum dmaengine_alignment {
* paused. Returns 0 or an error code
* @device_terminate_all: Aborts all transfers on a channel. Returns 0
* or an error code
+ * @device_synchronize: Synchronizes the termination of a transfers to the
+ * current context.
* @device_tx_status: poll for transaction completion, the optional
* txstate parameter can be supplied with a pointer to get a
* struct with auxiliary transfer status information, otherwise the call
* will just return a simple status code
* @device_issue_pending: push pending transactions to hardware
+ * @descriptor_reuse: a submitted transfer can be resubmitted after completion
*/
struct dma_device {
@@ -666,6 +696,7 @@ struct dma_device {
unsigned int privatecnt;
struct list_head channels;
struct list_head global_node;
+ struct dma_filter filter;
dma_cap_mask_t cap_mask;
unsigned short max_xor;
unsigned short max_pq;
@@ -681,6 +712,7 @@ struct dma_device {
u32 src_addr_widths;
u32 dst_addr_widths;
u32 directions;
+ bool descriptor_reuse;
enum dma_residue_granularity residue_granularity;
int (*device_alloc_chan_resources)(struct dma_chan *chan);
@@ -737,6 +769,7 @@ struct dma_device {
int (*device_pause)(struct dma_chan *chan);
int (*device_resume)(struct dma_chan *chan);
int (*device_terminate_all)(struct dma_chan *chan);
+ void (*device_synchronize)(struct dma_chan *chan);
enum dma_status (*device_tx_status)(struct dma_chan *chan,
dma_cookie_t cookie,
@@ -828,6 +861,13 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_sg(
src_sg, src_nents, flags);
}
+/**
+ * dmaengine_terminate_all() - Terminate all active DMA transfers
+ * @chan: The channel for which to terminate the transfers
+ *
+ * This function is DEPRECATED use either dmaengine_terminate_sync() or
+ * dmaengine_terminate_async() instead.
+ */
static inline int dmaengine_terminate_all(struct dma_chan *chan)
{
if (chan->device->device_terminate_all)
@@ -836,6 +876,88 @@ static inline int dmaengine_terminate_all(struct dma_chan *chan)
return -ENOSYS;
}
+/**
+ * dmaengine_terminate_async() - Terminate all active DMA transfers
+ * @chan: The channel for which to terminate the transfers
+ *
+ * Calling this function will terminate all active and pending descriptors
+ * that have previously been submitted to the channel. It is not guaranteed
+ * though that the transfer for the active descriptor has stopped when the
+ * function returns. Furthermore it is possible the complete callback of a
+ * submitted transfer is still running when this function returns.
+ *
+ * dmaengine_synchronize() needs to be called before it is safe to free
+ * any memory that is accessed by previously submitted descriptors or before
+ * freeing any resources accessed from within the completion callback of any
+ * perviously submitted descriptors.
+ *
+ * This function can be called from atomic context as well as from within a
+ * complete callback of a descriptor submitted on the same channel.
+ *
+ * If none of the two conditions above apply consider using
+ * dmaengine_terminate_sync() instead.
+ */
+static inline int dmaengine_terminate_async(struct dma_chan *chan)
+{
+ if (chan->device->device_terminate_all)
+ return chan->device->device_terminate_all(chan);
+
+ return -EINVAL;
+}
+
+/**
+ * dmaengine_synchronize() - Synchronize DMA channel termination
+ * @chan: The channel to synchronize
+ *
+ * Synchronizes to the DMA channel termination to the current context. When this
+ * function returns it is guaranteed that all transfers for previously issued
+ * descriptors have stopped and and it is safe to free the memory assoicated
+ * with them. Furthermore it is guaranteed that all complete callback functions
+ * for a previously submitted descriptor have finished running and it is safe to
+ * free resources accessed from within the complete callbacks.
+ *
+ * The behavior of this function is undefined if dma_async_issue_pending() has
+ * been called between dmaengine_terminate_async() and this function.
+ *
+ * This function must only be called from non-atomic context and must not be
+ * called from within a complete callback of a descriptor submitted on the same
+ * channel.
+ */
+static inline void dmaengine_synchronize(struct dma_chan *chan)
+{
+ might_sleep();
+
+ if (chan->device->device_synchronize)
+ chan->device->device_synchronize(chan);
+}
+
+/**
+ * dmaengine_terminate_sync() - Terminate all active DMA transfers
+ * @chan: The channel for which to terminate the transfers
+ *
+ * Calling this function will terminate all active and pending transfers
+ * that have previously been submitted to the channel. It is similar to
+ * dmaengine_terminate_async() but guarantees that the DMA transfer has actually
+ * stopped and that all complete callbacks have finished running when the
+ * function returns.
+ *
+ * This function must only be called from non-atomic context and must not be
+ * called from within a complete callback of a descriptor submitted on the same
+ * channel.
+ */
+static inline int dmaengine_terminate_sync(struct dma_chan *chan)
+{
+ int ret;
+
+ ret = dmaengine_terminate_async(chan);
+ if (ret)
+ return ret;
+
+ dmaengine_synchronize(chan);
+
+ return 0;
+}
+
static inline int dmaengine_pause(struct dma_chan *chan)
{
if (chan->device->device_pause)
@@ -1140,9 +1262,11 @@ enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx);
void dma_issue_pending_all(void);
struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
dma_filter_fn fn, void *fn_param);
-struct dma_chan *dma_request_slave_channel_reason(struct device *dev,
- const char *name);
struct dma_chan *dma_request_slave_channel(struct device *dev, const char *name);
+
+struct dma_chan *dma_request_chan(struct device *dev, const char *name);
+struct dma_chan *dma_request_chan_by_mask(const dma_cap_mask_t *mask);
+
void dma_release_channel(struct dma_chan *chan);
int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps);
#else
@@ -1166,16 +1290,21 @@ static inline struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
{
return NULL;
}
-static inline struct dma_chan *dma_request_slave_channel_reason(
- struct device *dev, const char *name)
-{
- return ERR_PTR(-ENODEV);
-}
static inline struct dma_chan *dma_request_slave_channel(struct device *dev,
const char *name)
{
return NULL;
}
+static inline struct dma_chan *dma_request_chan(struct device *dev,
+ const char *name)
+{
+ return ERR_PTR(-ENODEV);
+}
+static inline struct dma_chan *dma_request_chan_by_mask(
+ const dma_cap_mask_t *mask)
+{
+ return ERR_PTR(-ENODEV);
+}
static inline void dma_release_channel(struct dma_chan *chan)
{
}
@@ -1186,6 +1315,8 @@ static inline int dma_get_slave_caps(struct dma_chan *chan,
}
#endif
+#define dma_request_slave_channel_reason(dev, name) dma_request_chan(dev, name)
+
static inline int dmaengine_desc_set_reuse(struct dma_async_tx_descriptor *tx)
{
struct dma_slave_caps caps;