aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-bcmring/include/mach/dma.h
blob: 13e01384d6fca5e9106e08d41f7f2f8be7921304 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
/*****************************************************************************
* Copyright 2004 - 2008 Broadcom Corporation.  All rights reserved.
*
* Unless you and Broadcom execute a separate written software license
* agreement governing use of this software, this software is licensed to you
* under the terms of the GNU General Public License version 2, available at
* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
*
* Notwithstanding the above, under no circumstances may you combine this
* software in any way with any other Broadcom software provided under a
* license other than the GPL, without Broadcom's express prior written
* consent.
*****************************************************************************/

/****************************************************************************/
/**
*   @file   dma.h
*
*   @brief  API definitions for the linux DMA interface.
*/
/****************************************************************************/

#if !defined(ASM_ARM_ARCH_BCMRING_DMA_H)
#define ASM_ARM_ARCH_BCMRING_DMA_H

/* ---- Include Files ---------------------------------------------------- */

#include <linux/kernel.h>
#include <linux/semaphore.h>
#include <mach/csp/dmacHw.h>
#include <mach/timer.h>

/* ---- Constants and Types ---------------------------------------------- */

/* If DMA_DEBUG_TRACK_RESERVATION is set to a non-zero value, then the filename */
/* and line number of the reservation request will be recorded in the channel table */

#define DMA_DEBUG_TRACK_RESERVATION   1

#define DMA_NUM_CONTROLLERS     2
#define DMA_NUM_CHANNELS        8	/* per controller */

typedef enum {
	DMA_DEVICE_MEM_TO_MEM,	/* For memory to memory transfers */
	DMA_DEVICE_I2S0_DEV_TO_MEM,
	DMA_DEVICE_I2S0_MEM_TO_DEV,
	DMA_DEVICE_I2S1_DEV_TO_MEM,
	DMA_DEVICE_I2S1_MEM_TO_DEV,
	DMA_DEVICE_APM_CODEC_A_DEV_TO_MEM,
	DMA_DEVICE_APM_CODEC_A_MEM_TO_DEV,
	DMA_DEVICE_APM_CODEC_B_DEV_TO_MEM,
	DMA_DEVICE_APM_CODEC_B_MEM_TO_DEV,
	DMA_DEVICE_APM_CODEC_C_DEV_TO_MEM,	/* Additional mic input for beam-forming */
	DMA_DEVICE_APM_PCM0_DEV_TO_MEM,
	DMA_DEVICE_APM_PCM0_MEM_TO_DEV,
	DMA_DEVICE_APM_PCM1_DEV_TO_MEM,
	DMA_DEVICE_APM_PCM1_MEM_TO_DEV,
	DMA_DEVICE_SPUM_DEV_TO_MEM,
	DMA_DEVICE_SPUM_MEM_TO_DEV,
	DMA_DEVICE_SPIH_DEV_TO_MEM,
	DMA_DEVICE_SPIH_MEM_TO_DEV,
	DMA_DEVICE_UART_A_DEV_TO_MEM,
	DMA_DEVICE_UART_A_MEM_TO_DEV,
	DMA_DEVICE_UART_B_DEV_TO_MEM,
	DMA_DEVICE_UART_B_MEM_TO_DEV,
	DMA_DEVICE_PIF_MEM_TO_DEV,
	DMA_DEVICE_PIF_DEV_TO_MEM,
	DMA_DEVICE_ESW_DEV_TO_MEM,
	DMA_DEVICE_ESW_MEM_TO_DEV,
	DMA_DEVICE_VPM_MEM_TO_MEM,
	DMA_DEVICE_CLCD_MEM_TO_MEM,
	DMA_DEVICE_NAND_MEM_TO_MEM,
	DMA_DEVICE_MEM_TO_VRAM,
	DMA_DEVICE_VRAM_TO_MEM,

	/* Add new entries before this line. */

	DMA_NUM_DEVICE_ENTRIES,
	DMA_DEVICE_NONE = 0xff,	/* Special value to indicate that no device is currently assigned. */

} DMA_Device_t;

/****************************************************************************
*
*   The DMA_Handle_t is the primary object used by callers of the API.
*
*****************************************************************************/

#define DMA_INVALID_HANDLE  ((DMA_Handle_t) -1)

typedef int DMA_Handle_t;

/****************************************************************************
*
*   The DMA_DescriptorRing_t contains a ring of descriptors which is used
*   to point to regions of memory.
*
*****************************************************************************/

typedef struct {
	void *virtAddr;		/* Virtual Address of the descriptor ring */
	dma_addr_t physAddr;	/* Physical address of the descriptor ring */
	int descriptorsAllocated;	/* Number of descriptors allocated in the descriptor ring */
	size_t bytesAllocated;	/* Number of bytes allocated in the descriptor ring */

} DMA_DescriptorRing_t;

/****************************************************************************
*
*   The DMA_DeviceAttribute_t contains information which describes a
*   particular DMA device (or peripheral).
*
*   It is anticipated that the arrary of DMA_DeviceAttribute_t's will be
*   statically initialized.
*
*****************************************************************************/

/* The device handler is called whenever a DMA operation completes. The reaon */
/* for it to be called will be a bitmask with one or more of the following bits */
/* set. */

#define DMA_HANDLER_REASON_BLOCK_COMPLETE       dmacHw_INTERRUPT_STATUS_BLOCK
#define DMA_HANDLER_REASON_TRANSFER_COMPLETE    dmacHw_INTERRUPT_STATUS_TRANS
#define DMA_HANDLER_REASON_ERROR                dmacHw_INTERRUPT_STATUS_ERROR

typedef void (*DMA_DeviceHandler_t) (DMA_Device_t dev, int reason,
				     void *userData);

#define DMA_DEVICE_FLAG_ON_DMA0             0x00000001
#define DMA_DEVICE_FLAG_ON_DMA1             0x00000002
#define DMA_DEVICE_FLAG_PORT_PER_DMAC       0x00000004	/* If set, it means that the port used on DMAC0 is different from the port used on DMAC1 */
#define DMA_DEVICE_FLAG_ALLOC_DMA1_FIRST    0x00000008	/* If set, allocate from DMA1 before allocating from DMA0 */
#define DMA_DEVICE_FLAG_IS_DEDICATED        0x00000100
#define DMA_DEVICE_FLAG_NO_ISR              0x00000200
#define DMA_DEVICE_FLAG_ALLOW_LARGE_FIFO    0x00000400
#define DMA_DEVICE_FLAG_IN_USE              0x00000800	/* If set, device is in use on a channel */

/* Note: Some DMA devices can be used from multiple DMA Controllers. The bitmask is used to */
/*       determine which DMA controllers a given device can be used from, and the interface */
/*       array determeines the actual interface number to use for a given controller. */

typedef struct {
	uint32_t flags;		/* Bitmask of DMA_DEVICE_FLAG_xxx constants */
	uint8_t dedicatedController;	/* Controller number to use if DMA_DEVICE_FLAG_IS_DEDICATED is set. */
	uint8_t dedicatedChannel;	/* Channel number to use if DMA_DEVICE_FLAG_IS_DEDICATED is set. */
	const char *name;	/* Will show up in the /proc entry */

	uint32_t dmacPort[DMA_NUM_CONTROLLERS];	/* Specifies the port number when DMA_DEVICE_FLAG_PORT_PER_DMAC flag is set */

	dmacHw_CONFIG_t config;	/* Configuration to use when DMA'ing using this device */

	void *userData;		/* Passed to the devHandler */
	DMA_DeviceHandler_t devHandler;	/* Called when DMA operations finish. */

	timer_tick_count_t transferStartTime;	/* Time the current transfer was started */

	/* The following statistical information will be collected and presented in a proc entry. */
	/* Note: With a contiuous bandwidth of 1 Gb/sec, it would take 584 years to overflow */
	/*       a 64 bit counter. */

	uint64_t numTransfers;	/* Number of DMA transfers performed */
	uint64_t transferTicks;	/* Total time spent doing DMA transfers (measured in timer_tick_count_t's) */
	uint64_t transferBytes;	/* Total bytes transferred */
	uint32_t timesBlocked;	/* Number of times a channel was unavailable */
	uint32_t numBytes;	/* Last transfer size */

	/* It's not possible to free memory which is allocated for the descriptors from within */
	/* the ISR. So make the presumption that a given device will tend to use the */
	/* same sized buffers over and over again, and we keep them around. */

	DMA_DescriptorRing_t ring;	/* Ring of descriptors allocated for this device */

	/* We stash away some of the information from the previous transfer. If back-to-back */
	/* transfers are performed from the same buffer, then we don't have to keep re-initializing */
	/* the descriptor buffers. */

	uint32_t prevNumBytes;
	dma_addr_t prevSrcData;
	dma_addr_t prevDstData;

} DMA_DeviceAttribute_t;

/****************************************************************************
*
*   DMA_Channel_t, DMA_Controller_t, and DMA_State_t are really internal
*   data structures and don't belong in this header file, but are included
*   merely for discussion.
*
*   By the time this is implemented, these structures will be moved out into
*   the appropriate C source file instead.
*
*****************************************************************************/

/****************************************************************************
*
*   The DMA_Channel_t contains state information about each DMA channel. Some
*   of the channels are dedicated. Non-dedicated channels are shared
*   amongst the other devices.
*
*****************************************************************************/

#define DMA_CHANNEL_FLAG_IN_USE         0x00000001
#define DMA_CHANNEL_FLAG_IS_DEDICATED   0x00000002
#define DMA_CHANNEL_FLAG_NO_ISR         0x00000004
#define DMA_CHANNEL_FLAG_LARGE_FIFO     0x00000008

typedef struct {
	uint32_t flags;		/* bitmask of DMA_CHANNEL_FLAG_xxx constants */
	DMA_Device_t devType;	/* Device this channel is currently reserved for */
	DMA_Device_t lastDevType;	/* Device type that used this previously */
	char name[20];		/* Name passed onto request_irq */

#if (DMA_DEBUG_TRACK_RESERVATION)
	const char *fileName;	/* Place where channel reservation took place */
	int lineNum;		/* Place where channel reservation took place */
#endif
	dmacHw_HANDLE_t dmacHwHandle;	/* low level channel handle. */

} DMA_Channel_t;

/****************************************************************************
*
*   The DMA_Controller_t contains state information about each DMA controller.
*
*   The freeChannelQ is stored in the controller data structure rather than
*   the channel data structure since several of the devices are accessible
*   from multiple controllers, and there is no way to know which controller
*   will become available first.
*
*****************************************************************************/

typedef struct {
	DMA_Channel_t channel[DMA_NUM_CHANNELS];

} DMA_Controller_t;

/****************************************************************************
*
*   The DMA_Global_t contains all of the global state information used by
*   the DMA code.
*
*   Callers which need to allocate a shared channel will be queued up
*   on the freeChannelQ until a channel becomes available.
*
*****************************************************************************/

typedef struct {
	struct semaphore lock;	/* acquired when manipulating table entries */
	wait_queue_head_t freeChannelQ;

	DMA_Controller_t controller[DMA_NUM_CONTROLLERS];

} DMA_Global_t;

/* ---- Variable Externs ------------------------------------------------- */

extern DMA_DeviceAttribute_t DMA_gDeviceAttribute[DMA_NUM_DEVICE_ENTRIES];

/* ---- Function Prototypes ---------------------------------------------- */

#if defined(__KERNEL__)

/****************************************************************************/
/**
*   Initializes the DMA module.
*
*   @return
*       0       - Success
*       < 0     - Error
*/
/****************************************************************************/

int dma_init(void);

#if (DMA_DEBUG_TRACK_RESERVATION)
DMA_Handle_t dma_request_channel_dbg(DMA_Device_t dev, const char *fileName,
				     int lineNum);
#define dma_request_channel(dev)  dma_request_channel_dbg(dev, __FILE__, __LINE__)
#else

/****************************************************************************/
/**
*   Reserves a channel for use with @a dev. If the device is setup to use
*   a shared channel, then this function will block until a free channel
*   becomes available.
*
*   @return
*       >= 0    - A valid DMA Handle.
*       -EBUSY  - Device is currently being used.
*       -ENODEV - Device handed in is invalid.
*/
/****************************************************************************/

DMA_Handle_t dma_request_channel(DMA_Device_t dev	/* Device to use with the allocated channel. */
    );
#endif

/****************************************************************************/
/**
*   Frees a previously allocated DMA Handle.
*
*   @return
*        0      - DMA Handle was released successfully.
*       -EINVAL - Invalid DMA handle
*/
/****************************************************************************/

int dma_free_channel(DMA_Handle_t channel	/* DMA handle. */
    );

/****************************************************************************/
/**
*   Determines if a given device has been configured as using a shared
*   channel.
*
*   @return boolean
*       0           Device uses a dedicated channel
*       non-zero    Device uses a shared channel
*/
/****************************************************************************/

int dma_device_is_channel_shared(DMA_Device_t dev	/* Device to check. */
    );

/****************************************************************************/
/**
*   Allocates memory to hold a descriptor ring. The descriptor ring then
*   needs to be populated by making one or more calls to
*   dna_add_descriptors.
*
*   The returned descriptor ring will be automatically initialized.
*
*   @return
*       0           Descriptor ring was allocated successfully
*       -ENOMEM     Unable to allocate memory for the desired number of descriptors.
*/
/****************************************************************************/

int dma_alloc_descriptor_ring(DMA_DescriptorRing_t *ring,	/* Descriptor ring to populate */
			      int numDescriptors	/* Number of descriptors that need to be allocated. */
    );

/****************************************************************************/
/**
*   Releases the memory which was previously allocated for a descriptor ring.
*/
/****************************************************************************/

void dma_free_descriptor_ring(DMA_DescriptorRing_t *ring	/* Descriptor to release */
    );

/****************************************************************************/
/**
*   Initializes a descriptor ring, so that descriptors can be added to it.
*   Once a descriptor ring has been allocated, it may be reinitialized for
*   use with additional/different regions of memory.
*
*   Note that if 7 descriptors are allocated, it's perfectly acceptable to
*   initialize the ring with a smaller number of descriptors. The amount
*   of memory allocated for the descriptor ring will not be reduced, and
*   the descriptor ring may be reinitialized later
*
*   @return
*       0           Descriptor ring was initialized successfully
*       -ENOMEM     The descriptor which was passed in has insufficient space
*                   to hold the desired number of descriptors.
*/
/****************************************************************************/

int dma_init_descriptor_ring(DMA_DescriptorRing_t *ring,	/* Descriptor ring to initialize */
			     int numDescriptors	/* Number of descriptors to initialize. */
    );

/****************************************************************************/
/**
*   Determines the number of descriptors which would be required for a
*   transfer of the indicated memory region.
*
*   This function also needs to know which DMA device this transfer will
*   be destined for, so that the appropriate DMA configuration can be retrieved.
*   DMA parameters such as transfer width, and whether this is a memory-to-memory
*   or memory-to-peripheral, etc can all affect the actual number of descriptors
*   required.
*
*   @return
*       > 0     Returns the number of descriptors required for the indicated transfer
*       -EINVAL Invalid device type for this kind of transfer
*               (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
*       -ENOMEM Memory exhausted
*/
/****************************************************************************/

int dma_calculate_descriptor_count(DMA_Device_t device,	/* DMA Device that this will be associated with */
				   dma_addr_t srcData,	/* Place to get data to write to device */
				   dma_addr_t dstData,	/* Pointer to device data address */
				   size_t numBytes	/* Number of bytes to transfer to the device */
    );

/****************************************************************************/
/**
*   Adds a region of memory to the descriptor ring. Note that it may take
*   multiple descriptors for each region of memory. It is the callers
*   responsibility to allocate a sufficiently large descriptor ring.
*
*   @return
*       0       Descriptors were added successfully
*       -EINVAL Invalid device type for this kind of transfer
*               (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
*       -ENOMEM Memory exhausted
*/
/****************************************************************************/

int dma_add_descriptors(DMA_DescriptorRing_t *ring,	/* Descriptor ring to add descriptors to */
			DMA_Device_t device,	/* DMA Device that descriptors are for */
			dma_addr_t srcData,	/* Place to get data (memory or device) */
			dma_addr_t dstData,	/* Place to put data (memory or device) */
			size_t numBytes	/* Number of bytes to transfer to the device */
    );

/****************************************************************************/
/**
*   Sets the descriptor ring associated with a device.
*
*   Once set, the descriptor ring will be associated with the device, even
*   across channel request/free calls. Passing in a NULL descriptor ring
*   will release any descriptor ring currently associated with the device.
*
*   Note: If you call dma_transfer, or one of the other dma_alloc_ functions
*         the descriptor ring may be released and reallocated.
*
*   Note: This function will release the descriptor memory for any current
*         descriptor ring associated with this device.
*/
/****************************************************************************/

int dma_set_device_descriptor_ring(DMA_Device_t device,	/* Device to update the descriptor ring for. */
				   DMA_DescriptorRing_t *ring	/* Descriptor ring to add descriptors to */
    );

/****************************************************************************/
/**
*   Retrieves the descriptor ring associated with a device.
*/
/****************************************************************************/

int dma_get_device_descriptor_ring(DMA_Device_t device,	/* Device to retrieve the descriptor ring for. */
				   DMA_DescriptorRing_t *ring	/* Place to store retrieved ring */
    );

/****************************************************************************/
/**
*   Allocates buffers for the descriptors. This is normally done automatically
*   but needs to be done explicitly when initiating a dma from interrupt
*   context.
*
*   @return
*       0       Descriptors were allocated successfully
*       -EINVAL Invalid device type for this kind of transfer
*               (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
*       -ENOMEM Memory exhausted
*/
/****************************************************************************/

int dma_alloc_descriptors(DMA_Handle_t handle,	/* DMA Handle */
			  dmacHw_TRANSFER_TYPE_e transferType,	/* Type of transfer being performed */
			  dma_addr_t srcData,	/* Place to get data to write to device */
			  dma_addr_t dstData,	/* Pointer to device data address */
			  size_t numBytes	/* Number of bytes to transfer to the device */
    );

/****************************************************************************/
/**
*   Allocates and sets up descriptors for a double buffered circular buffer.
*
*   This is primarily intended to be used for things like the ingress samples
*   from a microphone.
*
*   @return
*       > 0     Number of descriptors actually allocated.
*       -EINVAL Invalid device type for this kind of transfer
*               (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
*       -ENOMEM Memory exhausted
*/
/****************************************************************************/

int dma_alloc_double_dst_descriptors(DMA_Handle_t handle,	/* DMA Handle */
				     dma_addr_t srcData,	/* Physical address of source data */
				     dma_addr_t dstData1,	/* Physical address of first destination buffer */
				     dma_addr_t dstData2,	/* Physical address of second destination buffer */
				     size_t numBytes	/* Number of bytes in each destination buffer */
    );

/****************************************************************************/
/**
*   Initiates a transfer when the descriptors have already been setup.
*
*   This is a special case, and normally, the dma_transfer_xxx functions should
*   be used.
*
*   @return
*       0       Transfer was started successfully
*       -ENODEV Invalid handle
*/
/****************************************************************************/

int dma_start_transfer(DMA_Handle_t handle);

/****************************************************************************/
/**
*   Stops a previously started DMA transfer.
*
*   @return
*       0       Transfer was stopped successfully
*       -ENODEV Invalid handle
*/
/****************************************************************************/

int dma_stop_transfer(DMA_Handle_t handle);

/****************************************************************************/
/**
*   Waits for a DMA to complete by polling. This function is only intended
*   to be used for testing. Interrupts should be used for most DMA operations.
*/
/****************************************************************************/

int dma_wait_transfer_done(DMA_Handle_t handle);

/****************************************************************************/
/**
*   Initiates a DMA transfer
*
*   @return
*       0       Transfer was started successfully
*       -EINVAL Invalid device type for this kind of transfer
*               (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
*/
/****************************************************************************/

int dma_transfer(DMA_Handle_t handle,	/* DMA Handle */
		 dmacHw_TRANSFER_TYPE_e transferType,	/* Type of transfer being performed */
		 dma_addr_t srcData,	/* Place to get data to write to device */
		 dma_addr_t dstData,	/* Pointer to device data address */
		 size_t numBytes	/* Number of bytes to transfer to the device */
    );

/****************************************************************************/
/**
*   Initiates a transfer from memory to a device.
*
*   @return
*       0       Transfer was started successfully
*       -EINVAL Invalid device type for this kind of transfer
*               (i.e. the device is _DEV_TO_MEM and not _MEM_TO_DEV)
*/
/****************************************************************************/

static inline int dma_transfer_to_device(DMA_Handle_t handle,	/* DMA Handle */
					 dma_addr_t srcData,	/* Place to get data to write to device (physical address) */
					 dma_addr_t dstData,	/* Pointer to device data address (physical address) */
					 size_t numBytes	/* Number of bytes to transfer to the device */
    ) {
	return dma_transfer(handle,
			    dmacHw_TRANSFER_TYPE_MEM_TO_PERIPHERAL,
			    srcData, dstData, numBytes);
}

/****************************************************************************/
/**
*   Initiates a transfer from a device to memory.
*
*   @return
*       0       Transfer was started successfully
*       -EINVAL Invalid device type for this kind of transfer
*               (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
*/
/****************************************************************************/

static inline int dma_transfer_from_device(DMA_Handle_t handle,	/* DMA Handle */
					   dma_addr_t srcData,	/* Pointer to the device data address (physical address) */
					   dma_addr_t dstData,	/* Place to store data retrieved from the device (physical address) */
					   size_t numBytes	/* Number of bytes to retrieve from the device */
    ) {
	return dma_transfer(handle,
			    dmacHw_TRANSFER_TYPE_PERIPHERAL_TO_MEM,
			    srcData, dstData, numBytes);
}

/****************************************************************************/
/**
*   Initiates a memory to memory transfer.
*
*   @return
*       0       Transfer was started successfully
*       -EINVAL Invalid device type for this kind of transfer
*               (i.e. the device wasn't DMA_DEVICE_MEM_TO_MEM)
*/
/****************************************************************************/

static inline int dma_transfer_mem_to_mem(DMA_Handle_t handle,	/* DMA Handle */
					  dma_addr_t srcData,	/* Place to transfer data from (physical address) */
					  dma_addr_t dstData,	/* Place to transfer data to (physical address) */
					  size_t numBytes	/* Number of bytes to transfer */
    ) {
	return dma_transfer(handle,
			    dmacHw_TRANSFER_TYPE_MEM_TO_MEM,
			    srcData, dstData, numBytes);
}

/****************************************************************************/
/**
*   Set the callback function which will be called when a transfer completes.
*   If a NULL callback function is set, then no callback will occur.
*
*   @note   @a devHandler will be called from IRQ context.
*
*   @return
*       0       - Success
*       -ENODEV - Device handed in is invalid.
*/
/****************************************************************************/

int dma_set_device_handler(DMA_Device_t dev,	/* Device to set the callback for. */
			   DMA_DeviceHandler_t devHandler,	/* Function to call when the DMA completes */
			   void *userData	/* Pointer which will be passed to devHandler. */
    );

#endif

#endif /* ASM_ARM_ARCH_BCMRING_DMA_H */