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-rw-r--r--include/linux/dmaengine.h37
1 files changed, 37 insertions, 0 deletions
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 41cf0c399288..6fd9390ccf91 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -22,6 +22,7 @@
#define LINUX_DMAENGINE_H
#include <linux/device.h>
+#include <linux/err.h>
#include <linux/uio.h>
#include <linux/bug.h>
#include <linux/scatterlist.h>
@@ -363,6 +364,32 @@ struct dma_slave_config {
unsigned int slave_id;
};
+/**
+ * enum dma_residue_granularity - Granularity of the reported transfer residue
+ * @DMA_RESIDUE_GRANULARITY_DESCRIPTOR: Residue reporting is not support. The
+ * DMA channel is only able to tell whether a descriptor has been completed or
+ * not, which means residue reporting is not supported by this channel. The
+ * residue field of the dma_tx_state field will always be 0.
+ * @DMA_RESIDUE_GRANULARITY_SEGMENT: Residue is updated after each successfully
+ * completed segment of the transfer (For cyclic transfers this is after each
+ * period). This is typically implemented by having the hardware generate an
+ * interrupt after each transferred segment and then the drivers updates the
+ * outstanding residue by the size of the segment. Another possibility is if
+ * the hardware supports scatter-gather and the segment descriptor has a field
+ * which gets set after the segment has been completed. The driver then counts
+ * the number of segments without the flag set to compute the residue.
+ * @DMA_RESIDUE_GRANULARITY_BURST: Residue is updated after each transferred
+ * burst. This is typically only supported if the hardware has a progress
+ * register of some sort (E.g. a register with the current read/write address
+ * or a register with the amount of bursts/beats/bytes that have been
+ * transferred or still need to be transferred).
+ */
+enum dma_residue_granularity {
+ DMA_RESIDUE_GRANULARITY_DESCRIPTOR = 0,
+ DMA_RESIDUE_GRANULARITY_SEGMENT = 1,
+ DMA_RESIDUE_GRANULARITY_BURST = 2,
+};
+
/* struct dma_slave_caps - expose capabilities of a slave channel only
*
* @src_addr_widths: bit mask of src addr widths the channel supports
@@ -373,6 +400,7 @@ struct dma_slave_config {
* should be checked by controller as well
* @cmd_pause: true, if pause and thereby resume is supported
* @cmd_terminate: true, if terminate cmd is supported
+ * @residue_granularity: granularity of the reported transfer residue
*/
struct dma_slave_caps {
u32 src_addr_widths;
@@ -380,6 +408,7 @@ struct dma_slave_caps {
u32 directions;
bool cmd_pause;
bool cmd_terminate;
+ enum dma_residue_granularity residue_granularity;
};
static inline const char *dma_chan_name(struct dma_chan *chan)
@@ -1040,6 +1069,8 @@ 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);
void dma_release_channel(struct dma_chan *chan);
#else
@@ -1063,6 +1094,11 @@ 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)
{
@@ -1079,6 +1115,7 @@ int dma_async_device_register(struct dma_device *device);
void dma_async_device_unregister(struct dma_device *device);
void dma_run_dependencies(struct dma_async_tx_descriptor *tx);
struct dma_chan *dma_get_slave_channel(struct dma_chan *chan);
+struct dma_chan *dma_get_any_slave_channel(struct dma_device *device);
struct dma_chan *net_dma_find_channel(void);
#define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y)
#define dma_request_slave_channel_compat(mask, x, y, dev, name) \