1 /*
2 * Copyright(c) 2004 - 2006 Intel Corporation. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by the Free
6 * Software Foundation; either version 2 of the License, or (at your option)
7 * any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 59
16 * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
17 *
18 * The full GNU General Public License is included in this distribution in the
19 * file called COPYING.
20 */
21 #ifndef LINUX_DMAENGINE_H
22 #define LINUX_DMAENGINE_H
23
24 #include <linux/device.h>
25 #include <linux/err.h>
26 #include <linux/uio.h>
27 #include <linux/bug.h>
28 #include <linux/scatterlist.h>
29 #include <linux/bitmap.h>
30 #include <linux/types.h>
31 #include <asm/page.h>
32
33 /**
34 * typedef dma_cookie_t - an opaque DMA cookie
35 *
36 * if dma_cookie_t is >0 it's a DMA request cookie, <0 it's an error code
37 */
38 typedef s32 dma_cookie_t;
39 #define DMA_MIN_COOKIE 1
40
dma_submit_error(dma_cookie_t cookie)41 static inline int dma_submit_error(dma_cookie_t cookie)
42 {
43 return cookie < 0 ? cookie : 0;
44 }
45
46 /**
47 * enum dma_status - DMA transaction status
48 * @DMA_COMPLETE: transaction completed
49 * @DMA_IN_PROGRESS: transaction not yet processed
50 * @DMA_PAUSED: transaction is paused
51 * @DMA_ERROR: transaction failed
52 */
53 enum dma_status {
54 DMA_COMPLETE,
55 DMA_IN_PROGRESS,
56 DMA_PAUSED,
57 DMA_ERROR,
58 };
59
60 /**
61 * enum dma_transaction_type - DMA transaction types/indexes
62 *
63 * Note: The DMA_ASYNC_TX capability is not to be set by drivers. It is
64 * automatically set as dma devices are registered.
65 */
66 enum dma_transaction_type {
67 DMA_MEMCPY,
68 DMA_XOR,
69 DMA_PQ,
70 DMA_XOR_VAL,
71 DMA_PQ_VAL,
72 DMA_INTERRUPT,
73 DMA_SG,
74 DMA_PRIVATE,
75 DMA_ASYNC_TX,
76 DMA_SLAVE,
77 DMA_CYCLIC,
78 DMA_INTERLEAVE,
79 /* last transaction type for creation of the capabilities mask */
80 DMA_TX_TYPE_END,
81 };
82
83 /**
84 * enum dma_transfer_direction - dma transfer mode and direction indicator
85 * @DMA_MEM_TO_MEM: Async/Memcpy mode
86 * @DMA_MEM_TO_DEV: Slave mode & From Memory to Device
87 * @DMA_DEV_TO_MEM: Slave mode & From Device to Memory
88 * @DMA_DEV_TO_DEV: Slave mode & From Device to Device
89 */
90 enum dma_transfer_direction {
91 DMA_MEM_TO_MEM,
92 DMA_MEM_TO_DEV,
93 DMA_DEV_TO_MEM,
94 DMA_DEV_TO_DEV,
95 DMA_TRANS_NONE,
96 };
97
98 /**
99 * Interleaved Transfer Request
100 * ----------------------------
101 * A chunk is collection of contiguous bytes to be transfered.
102 * The gap(in bytes) between two chunks is called inter-chunk-gap(ICG).
103 * ICGs may or maynot change between chunks.
104 * A FRAME is the smallest series of contiguous {chunk,icg} pairs,
105 * that when repeated an integral number of times, specifies the transfer.
106 * A transfer template is specification of a Frame, the number of times
107 * it is to be repeated and other per-transfer attributes.
108 *
109 * Practically, a client driver would have ready a template for each
110 * type of transfer it is going to need during its lifetime and
111 * set only 'src_start' and 'dst_start' before submitting the requests.
112 *
113 *
114 * | Frame-1 | Frame-2 | ~ | Frame-'numf' |
115 * |====....==.===...=...|====....==.===...=...| ~ |====....==.===...=...|
116 *
117 * == Chunk size
118 * ... ICG
119 */
120
121 /**
122 * struct data_chunk - Element of scatter-gather list that makes a frame.
123 * @size: Number of bytes to read from source.
124 * size_dst := fn(op, size_src), so doesn't mean much for destination.
125 * @icg: Number of bytes to jump after last src/dst address of this
126 * chunk and before first src/dst address for next chunk.
127 * Ignored for dst(assumed 0), if dst_inc is true and dst_sgl is false.
128 * Ignored for src(assumed 0), if src_inc is true and src_sgl is false.
129 */
130 struct data_chunk {
131 size_t size;
132 size_t icg;
133 };
134
135 /**
136 * struct dma_interleaved_template - Template to convey DMAC the transfer pattern
137 * and attributes.
138 * @src_start: Bus address of source for the first chunk.
139 * @dst_start: Bus address of destination for the first chunk.
140 * @dir: Specifies the type of Source and Destination.
141 * @src_inc: If the source address increments after reading from it.
142 * @dst_inc: If the destination address increments after writing to it.
143 * @src_sgl: If the 'icg' of sgl[] applies to Source (scattered read).
144 * Otherwise, source is read contiguously (icg ignored).
145 * Ignored if src_inc is false.
146 * @dst_sgl: If the 'icg' of sgl[] applies to Destination (scattered write).
147 * Otherwise, destination is filled contiguously (icg ignored).
148 * Ignored if dst_inc is false.
149 * @numf: Number of frames in this template.
150 * @frame_size: Number of chunks in a frame i.e, size of sgl[].
151 * @sgl: Array of {chunk,icg} pairs that make up a frame.
152 */
153 struct dma_interleaved_template {
154 dma_addr_t src_start;
155 dma_addr_t dst_start;
156 enum dma_transfer_direction dir;
157 bool src_inc;
158 bool dst_inc;
159 bool src_sgl;
160 bool dst_sgl;
161 size_t numf;
162 size_t frame_size;
163 struct data_chunk sgl[0];
164 };
165
166 /**
167 * enum dma_ctrl_flags - DMA flags to augment operation preparation,
168 * control completion, and communicate status.
169 * @DMA_PREP_INTERRUPT - trigger an interrupt (callback) upon completion of
170 * this transaction
171 * @DMA_CTRL_ACK - if clear, the descriptor cannot be reused until the client
172 * acknowledges receipt, i.e. has has a chance to establish any dependency
173 * chains
174 * @DMA_PREP_PQ_DISABLE_P - prevent generation of P while generating Q
175 * @DMA_PREP_PQ_DISABLE_Q - prevent generation of Q while generating P
176 * @DMA_PREP_CONTINUE - indicate to a driver that it is reusing buffers as
177 * sources that were the result of a previous operation, in the case of a PQ
178 * operation it continues the calculation with new sources
179 * @DMA_PREP_FENCE - tell the driver that subsequent operations depend
180 * on the result of this operation
181 */
182 enum dma_ctrl_flags {
183 DMA_PREP_INTERRUPT = (1 << 0),
184 DMA_CTRL_ACK = (1 << 1),
185 DMA_PREP_PQ_DISABLE_P = (1 << 2),
186 DMA_PREP_PQ_DISABLE_Q = (1 << 3),
187 DMA_PREP_CONTINUE = (1 << 4),
188 DMA_PREP_FENCE = (1 << 5),
189 };
190
191 /**
192 * enum dma_ctrl_cmd - DMA operations that can optionally be exercised
193 * on a running channel.
194 * @DMA_TERMINATE_ALL: terminate all ongoing transfers
195 * @DMA_PAUSE: pause ongoing transfers
196 * @DMA_RESUME: resume paused transfer
197 * @DMA_SLAVE_CONFIG: this command is only implemented by DMA controllers
198 * that need to runtime reconfigure the slave channels (as opposed to passing
199 * configuration data in statically from the platform). An additional
200 * argument of struct dma_slave_config must be passed in with this
201 * command.
202 */
203 enum dma_ctrl_cmd {
204 DMA_TERMINATE_ALL,
205 DMA_PAUSE,
206 DMA_RESUME,
207 DMA_SLAVE_CONFIG,
208 };
209
210 /**
211 * enum sum_check_bits - bit position of pq_check_flags
212 */
213 enum sum_check_bits {
214 SUM_CHECK_P = 0,
215 SUM_CHECK_Q = 1,
216 };
217
218 /**
219 * enum pq_check_flags - result of async_{xor,pq}_zero_sum operations
220 * @SUM_CHECK_P_RESULT - 1 if xor zero sum error, 0 otherwise
221 * @SUM_CHECK_Q_RESULT - 1 if reed-solomon zero sum error, 0 otherwise
222 */
223 enum sum_check_flags {
224 SUM_CHECK_P_RESULT = (1 << SUM_CHECK_P),
225 SUM_CHECK_Q_RESULT = (1 << SUM_CHECK_Q),
226 };
227
228
229 /**
230 * dma_cap_mask_t - capabilities bitmap modeled after cpumask_t.
231 * See linux/cpumask.h
232 */
233 typedef struct { DECLARE_BITMAP(bits, DMA_TX_TYPE_END); } dma_cap_mask_t;
234
235 /**
236 * struct dma_chan_percpu - the per-CPU part of struct dma_chan
237 * @memcpy_count: transaction counter
238 * @bytes_transferred: byte counter
239 */
240
241 struct dma_chan_percpu {
242 /* stats */
243 unsigned long memcpy_count;
244 unsigned long bytes_transferred;
245 };
246
247 /**
248 * struct dma_chan - devices supply DMA channels, clients use them
249 * @device: ptr to the dma device who supplies this channel, always !%NULL
250 * @cookie: last cookie value returned to client
251 * @completed_cookie: last completed cookie for this channel
252 * @chan_id: channel ID for sysfs
253 * @dev: class device for sysfs
254 * @device_node: used to add this to the device chan list
255 * @local: per-cpu pointer to a struct dma_chan_percpu
256 * @client_count: how many clients are using this channel
257 * @table_count: number of appearances in the mem-to-mem allocation table
258 * @private: private data for certain client-channel associations
259 */
260 struct dma_chan {
261 struct dma_device *device;
262 dma_cookie_t cookie;
263 dma_cookie_t completed_cookie;
264
265 /* sysfs */
266 int chan_id;
267 struct dma_chan_dev *dev;
268
269 struct list_head device_node;
270 struct dma_chan_percpu __percpu *local;
271 int client_count;
272 int table_count;
273 void *private;
274 };
275
276 /**
277 * struct dma_chan_dev - relate sysfs device node to backing channel device
278 * @chan: driver channel device
279 * @device: sysfs device
280 * @dev_id: parent dma_device dev_id
281 * @idr_ref: reference count to gate release of dma_device dev_id
282 */
283 struct dma_chan_dev {
284 struct dma_chan *chan;
285 struct device device;
286 int dev_id;
287 atomic_t *idr_ref;
288 };
289
290 /**
291 * enum dma_slave_buswidth - defines bus width of the DMA slave
292 * device, source or target buses
293 */
294 enum dma_slave_buswidth {
295 DMA_SLAVE_BUSWIDTH_UNDEFINED = 0,
296 DMA_SLAVE_BUSWIDTH_1_BYTE = 1,
297 DMA_SLAVE_BUSWIDTH_2_BYTES = 2,
298 DMA_SLAVE_BUSWIDTH_3_BYTES = 3,
299 DMA_SLAVE_BUSWIDTH_4_BYTES = 4,
300 DMA_SLAVE_BUSWIDTH_8_BYTES = 8,
301 };
302
303 /**
304 * struct dma_slave_config - dma slave channel runtime config
305 * @direction: whether the data shall go in or out on this slave
306 * channel, right now. DMA_MEM_TO_DEV and DMA_DEV_TO_MEM are
307 * legal values. DEPRECATED, drivers should use the direction argument
308 * to the device_prep_slave_sg and device_prep_dma_cyclic functions or
309 * the dir field in the dma_interleaved_template structure.
310 * @src_addr: this is the physical address where DMA slave data
311 * should be read (RX), if the source is memory this argument is
312 * ignored.
313 * @dst_addr: this is the physical address where DMA slave data
314 * should be written (TX), if the source is memory this argument
315 * is ignored.
316 * @src_addr_width: this is the width in bytes of the source (RX)
317 * register where DMA data shall be read. If the source
318 * is memory this may be ignored depending on architecture.
319 * Legal values: 1, 2, 4, 8.
320 * @dst_addr_width: same as src_addr_width but for destination
321 * target (TX) mutatis mutandis.
322 * @src_maxburst: the maximum number of words (note: words, as in
323 * units of the src_addr_width member, not bytes) that can be sent
324 * in one burst to the device. Typically something like half the
325 * FIFO depth on I/O peripherals so you don't overflow it. This
326 * may or may not be applicable on memory sources.
327 * @dst_maxburst: same as src_maxburst but for destination target
328 * mutatis mutandis.
329 * @device_fc: Flow Controller Settings. Only valid for slave channels. Fill
330 * with 'true' if peripheral should be flow controller. Direction will be
331 * selected at Runtime.
332 * @slave_id: Slave requester id. Only valid for slave channels. The dma
333 * slave peripheral will have unique id as dma requester which need to be
334 * pass as slave config.
335 *
336 * This struct is passed in as configuration data to a DMA engine
337 * in order to set up a certain channel for DMA transport at runtime.
338 * The DMA device/engine has to provide support for an additional
339 * command in the channel config interface, DMA_SLAVE_CONFIG
340 * and this struct will then be passed in as an argument to the
341 * DMA engine device_control() function.
342 *
343 * The rationale for adding configuration information to this struct is as
344 * follows: if it is likely that more than one DMA slave controllers in
345 * the world will support the configuration option, then make it generic.
346 * If not: if it is fixed so that it be sent in static from the platform
347 * data, then prefer to do that.
348 */
349 struct dma_slave_config {
350 enum dma_transfer_direction direction;
351 dma_addr_t src_addr;
352 dma_addr_t dst_addr;
353 enum dma_slave_buswidth src_addr_width;
354 enum dma_slave_buswidth dst_addr_width;
355 u32 src_maxburst;
356 u32 dst_maxburst;
357 bool device_fc;
358 unsigned int slave_id;
359 };
360
361 /**
362 * enum dma_residue_granularity - Granularity of the reported transfer residue
363 * @DMA_RESIDUE_GRANULARITY_DESCRIPTOR: Residue reporting is not support. The
364 * DMA channel is only able to tell whether a descriptor has been completed or
365 * not, which means residue reporting is not supported by this channel. The
366 * residue field of the dma_tx_state field will always be 0.
367 * @DMA_RESIDUE_GRANULARITY_SEGMENT: Residue is updated after each successfully
368 * completed segment of the transfer (For cyclic transfers this is after each
369 * period). This is typically implemented by having the hardware generate an
370 * interrupt after each transferred segment and then the drivers updates the
371 * outstanding residue by the size of the segment. Another possibility is if
372 * the hardware supports scatter-gather and the segment descriptor has a field
373 * which gets set after the segment has been completed. The driver then counts
374 * the number of segments without the flag set to compute the residue.
375 * @DMA_RESIDUE_GRANULARITY_BURST: Residue is updated after each transferred
376 * burst. This is typically only supported if the hardware has a progress
377 * register of some sort (E.g. a register with the current read/write address
378 * or a register with the amount of bursts/beats/bytes that have been
379 * transferred or still need to be transferred).
380 */
381 enum dma_residue_granularity {
382 DMA_RESIDUE_GRANULARITY_DESCRIPTOR = 0,
383 DMA_RESIDUE_GRANULARITY_SEGMENT = 1,
384 DMA_RESIDUE_GRANULARITY_BURST = 2,
385 };
386
387 /* struct dma_slave_caps - expose capabilities of a slave channel only
388 *
389 * @src_addr_widths: bit mask of src addr widths the channel supports
390 * @dstn_addr_widths: bit mask of dstn addr widths the channel supports
391 * @directions: bit mask of slave direction the channel supported
392 * since the enum dma_transfer_direction is not defined as bits for each
393 * type of direction, the dma controller should fill (1 << <TYPE>) and same
394 * should be checked by controller as well
395 * @cmd_pause: true, if pause and thereby resume is supported
396 * @cmd_terminate: true, if terminate cmd is supported
397 * @residue_granularity: granularity of the reported transfer residue
398 */
399 struct dma_slave_caps {
400 u32 src_addr_widths;
401 u32 dstn_addr_widths;
402 u32 directions;
403 bool cmd_pause;
404 bool cmd_terminate;
405 enum dma_residue_granularity residue_granularity;
406 };
407
dma_chan_name(struct dma_chan * chan)408 static inline const char *dma_chan_name(struct dma_chan *chan)
409 {
410 return dev_name(&chan->dev->device);
411 }
412
413 void dma_chan_cleanup(struct kref *kref);
414
415 /**
416 * typedef dma_filter_fn - callback filter for dma_request_channel
417 * @chan: channel to be reviewed
418 * @filter_param: opaque parameter passed through dma_request_channel
419 *
420 * When this optional parameter is specified in a call to dma_request_channel a
421 * suitable channel is passed to this routine for further dispositioning before
422 * being returned. Where 'suitable' indicates a non-busy channel that
423 * satisfies the given capability mask. It returns 'true' to indicate that the
424 * channel is suitable.
425 */
426 typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param);
427
428 typedef void (*dma_async_tx_callback)(void *dma_async_param);
429
430 struct dmaengine_unmap_data {
431 u8 map_cnt;
432 u8 to_cnt;
433 u8 from_cnt;
434 u8 bidi_cnt;
435 struct device *dev;
436 struct kref kref;
437 size_t len;
438 dma_addr_t addr[0];
439 };
440
441 /**
442 * struct dma_async_tx_descriptor - async transaction descriptor
443 * ---dma generic offload fields---
444 * @cookie: tracking cookie for this transaction, set to -EBUSY if
445 * this tx is sitting on a dependency list
446 * @flags: flags to augment operation preparation, control completion, and
447 * communicate status
448 * @phys: physical address of the descriptor
449 * @chan: target channel for this operation
450 * @tx_submit: set the prepared descriptor(s) to be executed by the engine
451 * @callback: routine to call after this operation is complete
452 * @callback_param: general parameter to pass to the callback routine
453 * ---async_tx api specific fields---
454 * @next: at completion submit this descriptor
455 * @parent: pointer to the next level up in the dependency chain
456 * @lock: protect the parent and next pointers
457 */
458 struct dma_async_tx_descriptor {
459 dma_cookie_t cookie;
460 enum dma_ctrl_flags flags; /* not a 'long' to pack with cookie */
461 dma_addr_t phys;
462 struct dma_chan *chan;
463 dma_cookie_t (*tx_submit)(struct dma_async_tx_descriptor *tx);
464 dma_async_tx_callback callback;
465 void *callback_param;
466 struct dmaengine_unmap_data *unmap;
467 #ifdef CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH
468 struct dma_async_tx_descriptor *next;
469 struct dma_async_tx_descriptor *parent;
470 spinlock_t lock;
471 #endif
472 };
473
474 #ifdef CONFIG_DMA_ENGINE
dma_set_unmap(struct dma_async_tx_descriptor * tx,struct dmaengine_unmap_data * unmap)475 static inline void dma_set_unmap(struct dma_async_tx_descriptor *tx,
476 struct dmaengine_unmap_data *unmap)
477 {
478 kref_get(&unmap->kref);
479 tx->unmap = unmap;
480 }
481
482 struct dmaengine_unmap_data *
483 dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags);
484 void dmaengine_unmap_put(struct dmaengine_unmap_data *unmap);
485 #else
dma_set_unmap(struct dma_async_tx_descriptor * tx,struct dmaengine_unmap_data * unmap)486 static inline void dma_set_unmap(struct dma_async_tx_descriptor *tx,
487 struct dmaengine_unmap_data *unmap)
488 {
489 }
490 static inline struct dmaengine_unmap_data *
dmaengine_get_unmap_data(struct device * dev,int nr,gfp_t flags)491 dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags)
492 {
493 return NULL;
494 }
dmaengine_unmap_put(struct dmaengine_unmap_data * unmap)495 static inline void dmaengine_unmap_put(struct dmaengine_unmap_data *unmap)
496 {
497 }
498 #endif
499
dma_descriptor_unmap(struct dma_async_tx_descriptor * tx)500 static inline void dma_descriptor_unmap(struct dma_async_tx_descriptor *tx)
501 {
502 if (tx->unmap) {
503 dmaengine_unmap_put(tx->unmap);
504 tx->unmap = NULL;
505 }
506 }
507
508 #ifndef CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH
txd_lock(struct dma_async_tx_descriptor * txd)509 static inline void txd_lock(struct dma_async_tx_descriptor *txd)
510 {
511 }
txd_unlock(struct dma_async_tx_descriptor * txd)512 static inline void txd_unlock(struct dma_async_tx_descriptor *txd)
513 {
514 }
txd_chain(struct dma_async_tx_descriptor * txd,struct dma_async_tx_descriptor * next)515 static inline void txd_chain(struct dma_async_tx_descriptor *txd, struct dma_async_tx_descriptor *next)
516 {
517 BUG();
518 }
txd_clear_parent(struct dma_async_tx_descriptor * txd)519 static inline void txd_clear_parent(struct dma_async_tx_descriptor *txd)
520 {
521 }
txd_clear_next(struct dma_async_tx_descriptor * txd)522 static inline void txd_clear_next(struct dma_async_tx_descriptor *txd)
523 {
524 }
txd_next(struct dma_async_tx_descriptor * txd)525 static inline struct dma_async_tx_descriptor *txd_next(struct dma_async_tx_descriptor *txd)
526 {
527 return NULL;
528 }
txd_parent(struct dma_async_tx_descriptor * txd)529 static inline struct dma_async_tx_descriptor *txd_parent(struct dma_async_tx_descriptor *txd)
530 {
531 return NULL;
532 }
533
534 #else
txd_lock(struct dma_async_tx_descriptor * txd)535 static inline void txd_lock(struct dma_async_tx_descriptor *txd)
536 {
537 spin_lock_bh(&txd->lock);
538 }
txd_unlock(struct dma_async_tx_descriptor * txd)539 static inline void txd_unlock(struct dma_async_tx_descriptor *txd)
540 {
541 spin_unlock_bh(&txd->lock);
542 }
txd_chain(struct dma_async_tx_descriptor * txd,struct dma_async_tx_descriptor * next)543 static inline void txd_chain(struct dma_async_tx_descriptor *txd, struct dma_async_tx_descriptor *next)
544 {
545 txd->next = next;
546 next->parent = txd;
547 }
txd_clear_parent(struct dma_async_tx_descriptor * txd)548 static inline void txd_clear_parent(struct dma_async_tx_descriptor *txd)
549 {
550 txd->parent = NULL;
551 }
txd_clear_next(struct dma_async_tx_descriptor * txd)552 static inline void txd_clear_next(struct dma_async_tx_descriptor *txd)
553 {
554 txd->next = NULL;
555 }
txd_parent(struct dma_async_tx_descriptor * txd)556 static inline struct dma_async_tx_descriptor *txd_parent(struct dma_async_tx_descriptor *txd)
557 {
558 return txd->parent;
559 }
txd_next(struct dma_async_tx_descriptor * txd)560 static inline struct dma_async_tx_descriptor *txd_next(struct dma_async_tx_descriptor *txd)
561 {
562 return txd->next;
563 }
564 #endif
565
566 /**
567 * struct dma_tx_state - filled in to report the status of
568 * a transfer.
569 * @last: last completed DMA cookie
570 * @used: last issued DMA cookie (i.e. the one in progress)
571 * @residue: the remaining number of bytes left to transmit
572 * on the selected transfer for states DMA_IN_PROGRESS and
573 * DMA_PAUSED if this is implemented in the driver, else 0
574 */
575 struct dma_tx_state {
576 dma_cookie_t last;
577 dma_cookie_t used;
578 u32 residue;
579 };
580
581 /**
582 * struct dma_device - info on the entity supplying DMA services
583 * @chancnt: how many DMA channels are supported
584 * @privatecnt: how many DMA channels are requested by dma_request_channel
585 * @channels: the list of struct dma_chan
586 * @global_node: list_head for global dma_device_list
587 * @cap_mask: one or more dma_capability flags
588 * @max_xor: maximum number of xor sources, 0 if no capability
589 * @max_pq: maximum number of PQ sources and PQ-continue capability
590 * @copy_align: alignment shift for memcpy operations
591 * @xor_align: alignment shift for xor operations
592 * @pq_align: alignment shift for pq operations
593 * @fill_align: alignment shift for memset operations
594 * @dev_id: unique device ID
595 * @dev: struct device reference for dma mapping api
596 * @device_alloc_chan_resources: allocate resources and return the
597 * number of allocated descriptors
598 * @device_free_chan_resources: release DMA channel's resources
599 * @device_prep_dma_memcpy: prepares a memcpy operation
600 * @device_prep_dma_xor: prepares a xor operation
601 * @device_prep_dma_xor_val: prepares a xor validation operation
602 * @device_prep_dma_pq: prepares a pq operation
603 * @device_prep_dma_pq_val: prepares a pqzero_sum operation
604 * @device_prep_dma_interrupt: prepares an end of chain interrupt operation
605 * @device_prep_slave_sg: prepares a slave dma operation
606 * @device_prep_dma_cyclic: prepare a cyclic dma operation suitable for audio.
607 * The function takes a buffer of size buf_len. The callback function will
608 * be called after period_len bytes have been transferred.
609 * @device_prep_interleaved_dma: Transfer expression in a generic way.
610 * @device_control: manipulate all pending operations on a channel, returns
611 * zero or error code
612 * @device_tx_status: poll for transaction completion, the optional
613 * txstate parameter can be supplied with a pointer to get a
614 * struct with auxiliary transfer status information, otherwise the call
615 * will just return a simple status code
616 * @device_issue_pending: push pending transactions to hardware
617 * @device_slave_caps: return the slave channel capabilities
618 */
619 struct dma_device {
620
621 unsigned int chancnt;
622 unsigned int privatecnt;
623 struct list_head channels;
624 struct list_head global_node;
625 dma_cap_mask_t cap_mask;
626 unsigned short max_xor;
627 unsigned short max_pq;
628 u8 copy_align;
629 u8 xor_align;
630 u8 pq_align;
631 u8 fill_align;
632 #define DMA_HAS_PQ_CONTINUE (1 << 15)
633
634 int dev_id;
635 struct device *dev;
636
637 int (*device_alloc_chan_resources)(struct dma_chan *chan);
638 void (*device_free_chan_resources)(struct dma_chan *chan);
639
640 struct dma_async_tx_descriptor *(*device_prep_dma_memcpy)(
641 struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
642 size_t len, unsigned long flags);
643 struct dma_async_tx_descriptor *(*device_prep_dma_xor)(
644 struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
645 unsigned int src_cnt, size_t len, unsigned long flags);
646 struct dma_async_tx_descriptor *(*device_prep_dma_xor_val)(
647 struct dma_chan *chan, dma_addr_t *src, unsigned int src_cnt,
648 size_t len, enum sum_check_flags *result, unsigned long flags);
649 struct dma_async_tx_descriptor *(*device_prep_dma_pq)(
650 struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
651 unsigned int src_cnt, const unsigned char *scf,
652 size_t len, unsigned long flags);
653 struct dma_async_tx_descriptor *(*device_prep_dma_pq_val)(
654 struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
655 unsigned int src_cnt, const unsigned char *scf, size_t len,
656 enum sum_check_flags *pqres, unsigned long flags);
657 struct dma_async_tx_descriptor *(*device_prep_dma_interrupt)(
658 struct dma_chan *chan, unsigned long flags);
659 struct dma_async_tx_descriptor *(*device_prep_dma_sg)(
660 struct dma_chan *chan,
661 struct scatterlist *dst_sg, unsigned int dst_nents,
662 struct scatterlist *src_sg, unsigned int src_nents,
663 unsigned long flags);
664
665 struct dma_async_tx_descriptor *(*device_prep_slave_sg)(
666 struct dma_chan *chan, struct scatterlist *sgl,
667 unsigned int sg_len, enum dma_transfer_direction direction,
668 unsigned long flags, void *context);
669 struct dma_async_tx_descriptor *(*device_prep_dma_cyclic)(
670 struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
671 size_t period_len, enum dma_transfer_direction direction,
672 unsigned long flags);
673 struct dma_async_tx_descriptor *(*device_prep_interleaved_dma)(
674 struct dma_chan *chan, struct dma_interleaved_template *xt,
675 unsigned long flags);
676 int (*device_control)(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
677 unsigned long arg);
678
679 enum dma_status (*device_tx_status)(struct dma_chan *chan,
680 dma_cookie_t cookie,
681 struct dma_tx_state *txstate);
682 void (*device_issue_pending)(struct dma_chan *chan);
683 int (*device_slave_caps)(struct dma_chan *chan, struct dma_slave_caps *caps);
684 };
685
dmaengine_device_control(struct dma_chan * chan,enum dma_ctrl_cmd cmd,unsigned long arg)686 static inline int dmaengine_device_control(struct dma_chan *chan,
687 enum dma_ctrl_cmd cmd,
688 unsigned long arg)
689 {
690 if (chan->device->device_control)
691 return chan->device->device_control(chan, cmd, arg);
692
693 return -ENOSYS;
694 }
695
dmaengine_slave_config(struct dma_chan * chan,struct dma_slave_config * config)696 static inline int dmaengine_slave_config(struct dma_chan *chan,
697 struct dma_slave_config *config)
698 {
699 return dmaengine_device_control(chan, DMA_SLAVE_CONFIG,
700 (unsigned long)config);
701 }
702
is_slave_direction(enum dma_transfer_direction direction)703 static inline bool is_slave_direction(enum dma_transfer_direction direction)
704 {
705 return (direction == DMA_MEM_TO_DEV) || (direction == DMA_DEV_TO_MEM);
706 }
707
dmaengine_prep_slave_single(struct dma_chan * chan,dma_addr_t buf,size_t len,enum dma_transfer_direction dir,unsigned long flags)708 static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_single(
709 struct dma_chan *chan, dma_addr_t buf, size_t len,
710 enum dma_transfer_direction dir, unsigned long flags)
711 {
712 struct scatterlist sg;
713 sg_init_table(&sg, 1);
714 sg_dma_address(&sg) = buf;
715 sg_dma_len(&sg) = len;
716
717 return chan->device->device_prep_slave_sg(chan, &sg, 1,
718 dir, flags, NULL);
719 }
720
dmaengine_prep_slave_sg(struct dma_chan * chan,struct scatterlist * sgl,unsigned int sg_len,enum dma_transfer_direction dir,unsigned long flags)721 static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_sg(
722 struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len,
723 enum dma_transfer_direction dir, unsigned long flags)
724 {
725 return chan->device->device_prep_slave_sg(chan, sgl, sg_len,
726 dir, flags, NULL);
727 }
728
729 #ifdef CONFIG_RAPIDIO_DMA_ENGINE
730 struct rio_dma_ext;
dmaengine_prep_rio_sg(struct dma_chan * chan,struct scatterlist * sgl,unsigned int sg_len,enum dma_transfer_direction dir,unsigned long flags,struct rio_dma_ext * rio_ext)731 static inline struct dma_async_tx_descriptor *dmaengine_prep_rio_sg(
732 struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len,
733 enum dma_transfer_direction dir, unsigned long flags,
734 struct rio_dma_ext *rio_ext)
735 {
736 return chan->device->device_prep_slave_sg(chan, sgl, sg_len,
737 dir, flags, rio_ext);
738 }
739 #endif
740
dmaengine_prep_dma_cyclic(struct dma_chan * chan,dma_addr_t buf_addr,size_t buf_len,size_t period_len,enum dma_transfer_direction dir,unsigned long flags)741 static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_cyclic(
742 struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
743 size_t period_len, enum dma_transfer_direction dir,
744 unsigned long flags)
745 {
746 return chan->device->device_prep_dma_cyclic(chan, buf_addr, buf_len,
747 period_len, dir, flags);
748 }
749
dmaengine_prep_interleaved_dma(struct dma_chan * chan,struct dma_interleaved_template * xt,unsigned long flags)750 static inline struct dma_async_tx_descriptor *dmaengine_prep_interleaved_dma(
751 struct dma_chan *chan, struct dma_interleaved_template *xt,
752 unsigned long flags)
753 {
754 return chan->device->device_prep_interleaved_dma(chan, xt, flags);
755 }
756
dmaengine_prep_dma_sg(struct dma_chan * chan,struct scatterlist * dst_sg,unsigned int dst_nents,struct scatterlist * src_sg,unsigned int src_nents,unsigned long flags)757 static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_sg(
758 struct dma_chan *chan,
759 struct scatterlist *dst_sg, unsigned int dst_nents,
760 struct scatterlist *src_sg, unsigned int src_nents,
761 unsigned long flags)
762 {
763 return chan->device->device_prep_dma_sg(chan, dst_sg, dst_nents,
764 src_sg, src_nents, flags);
765 }
766
dma_get_slave_caps(struct dma_chan * chan,struct dma_slave_caps * caps)767 static inline int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps)
768 {
769 if (!chan || !caps)
770 return -EINVAL;
771
772 /* check if the channel supports slave transactions */
773 if (!test_bit(DMA_SLAVE, chan->device->cap_mask.bits))
774 return -ENXIO;
775
776 if (chan->device->device_slave_caps)
777 return chan->device->device_slave_caps(chan, caps);
778
779 return -ENXIO;
780 }
781
dmaengine_terminate_all(struct dma_chan * chan)782 static inline int dmaengine_terminate_all(struct dma_chan *chan)
783 {
784 return dmaengine_device_control(chan, DMA_TERMINATE_ALL, 0);
785 }
786
dmaengine_pause(struct dma_chan * chan)787 static inline int dmaengine_pause(struct dma_chan *chan)
788 {
789 return dmaengine_device_control(chan, DMA_PAUSE, 0);
790 }
791
dmaengine_resume(struct dma_chan * chan)792 static inline int dmaengine_resume(struct dma_chan *chan)
793 {
794 return dmaengine_device_control(chan, DMA_RESUME, 0);
795 }
796
dmaengine_tx_status(struct dma_chan * chan,dma_cookie_t cookie,struct dma_tx_state * state)797 static inline enum dma_status dmaengine_tx_status(struct dma_chan *chan,
798 dma_cookie_t cookie, struct dma_tx_state *state)
799 {
800 return chan->device->device_tx_status(chan, cookie, state);
801 }
802
dmaengine_submit(struct dma_async_tx_descriptor * desc)803 static inline dma_cookie_t dmaengine_submit(struct dma_async_tx_descriptor *desc)
804 {
805 return desc->tx_submit(desc);
806 }
807
dmaengine_check_align(u8 align,size_t off1,size_t off2,size_t len)808 static inline bool dmaengine_check_align(u8 align, size_t off1, size_t off2, size_t len)
809 {
810 size_t mask;
811
812 if (!align)
813 return true;
814 mask = (1 << align) - 1;
815 if (mask & (off1 | off2 | len))
816 return false;
817 return true;
818 }
819
is_dma_copy_aligned(struct dma_device * dev,size_t off1,size_t off2,size_t len)820 static inline bool is_dma_copy_aligned(struct dma_device *dev, size_t off1,
821 size_t off2, size_t len)
822 {
823 return dmaengine_check_align(dev->copy_align, off1, off2, len);
824 }
825
is_dma_xor_aligned(struct dma_device * dev,size_t off1,size_t off2,size_t len)826 static inline bool is_dma_xor_aligned(struct dma_device *dev, size_t off1,
827 size_t off2, size_t len)
828 {
829 return dmaengine_check_align(dev->xor_align, off1, off2, len);
830 }
831
is_dma_pq_aligned(struct dma_device * dev,size_t off1,size_t off2,size_t len)832 static inline bool is_dma_pq_aligned(struct dma_device *dev, size_t off1,
833 size_t off2, size_t len)
834 {
835 return dmaengine_check_align(dev->pq_align, off1, off2, len);
836 }
837
is_dma_fill_aligned(struct dma_device * dev,size_t off1,size_t off2,size_t len)838 static inline bool is_dma_fill_aligned(struct dma_device *dev, size_t off1,
839 size_t off2, size_t len)
840 {
841 return dmaengine_check_align(dev->fill_align, off1, off2, len);
842 }
843
844 static inline void
dma_set_maxpq(struct dma_device * dma,int maxpq,int has_pq_continue)845 dma_set_maxpq(struct dma_device *dma, int maxpq, int has_pq_continue)
846 {
847 dma->max_pq = maxpq;
848 if (has_pq_continue)
849 dma->max_pq |= DMA_HAS_PQ_CONTINUE;
850 }
851
dmaf_continue(enum dma_ctrl_flags flags)852 static inline bool dmaf_continue(enum dma_ctrl_flags flags)
853 {
854 return (flags & DMA_PREP_CONTINUE) == DMA_PREP_CONTINUE;
855 }
856
dmaf_p_disabled_continue(enum dma_ctrl_flags flags)857 static inline bool dmaf_p_disabled_continue(enum dma_ctrl_flags flags)
858 {
859 enum dma_ctrl_flags mask = DMA_PREP_CONTINUE | DMA_PREP_PQ_DISABLE_P;
860
861 return (flags & mask) == mask;
862 }
863
dma_dev_has_pq_continue(struct dma_device * dma)864 static inline bool dma_dev_has_pq_continue(struct dma_device *dma)
865 {
866 return (dma->max_pq & DMA_HAS_PQ_CONTINUE) == DMA_HAS_PQ_CONTINUE;
867 }
868
dma_dev_to_maxpq(struct dma_device * dma)869 static inline unsigned short dma_dev_to_maxpq(struct dma_device *dma)
870 {
871 return dma->max_pq & ~DMA_HAS_PQ_CONTINUE;
872 }
873
874 /* dma_maxpq - reduce maxpq in the face of continued operations
875 * @dma - dma device with PQ capability
876 * @flags - to check if DMA_PREP_CONTINUE and DMA_PREP_PQ_DISABLE_P are set
877 *
878 * When an engine does not support native continuation we need 3 extra
879 * source slots to reuse P and Q with the following coefficients:
880 * 1/ {00} * P : remove P from Q', but use it as a source for P'
881 * 2/ {01} * Q : use Q to continue Q' calculation
882 * 3/ {00} * Q : subtract Q from P' to cancel (2)
883 *
884 * In the case where P is disabled we only need 1 extra source:
885 * 1/ {01} * Q : use Q to continue Q' calculation
886 */
dma_maxpq(struct dma_device * dma,enum dma_ctrl_flags flags)887 static inline int dma_maxpq(struct dma_device *dma, enum dma_ctrl_flags flags)
888 {
889 if (dma_dev_has_pq_continue(dma) || !dmaf_continue(flags))
890 return dma_dev_to_maxpq(dma);
891 else if (dmaf_p_disabled_continue(flags))
892 return dma_dev_to_maxpq(dma) - 1;
893 else if (dmaf_continue(flags))
894 return dma_dev_to_maxpq(dma) - 3;
895 BUG();
896 }
897
898 /* --- public DMA engine API --- */
899
900 #ifdef CONFIG_DMA_ENGINE
901 void dmaengine_get(void);
902 void dmaengine_put(void);
903 #else
dmaengine_get(void)904 static inline void dmaengine_get(void)
905 {
906 }
dmaengine_put(void)907 static inline void dmaengine_put(void)
908 {
909 }
910 #endif
911
912 #ifdef CONFIG_ASYNC_TX_DMA
913 #define async_dmaengine_get() dmaengine_get()
914 #define async_dmaengine_put() dmaengine_put()
915 #ifndef CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH
916 #define async_dma_find_channel(type) dma_find_channel(DMA_ASYNC_TX)
917 #else
918 #define async_dma_find_channel(type) dma_find_channel(type)
919 #endif /* CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH */
920 #else
async_dmaengine_get(void)921 static inline void async_dmaengine_get(void)
922 {
923 }
async_dmaengine_put(void)924 static inline void async_dmaengine_put(void)
925 {
926 }
927 static inline struct dma_chan *
async_dma_find_channel(enum dma_transaction_type type)928 async_dma_find_channel(enum dma_transaction_type type)
929 {
930 return NULL;
931 }
932 #endif /* CONFIG_ASYNC_TX_DMA */
933 void dma_async_tx_descriptor_init(struct dma_async_tx_descriptor *tx,
934 struct dma_chan *chan);
935
async_tx_ack(struct dma_async_tx_descriptor * tx)936 static inline void async_tx_ack(struct dma_async_tx_descriptor *tx)
937 {
938 tx->flags |= DMA_CTRL_ACK;
939 }
940
async_tx_clear_ack(struct dma_async_tx_descriptor * tx)941 static inline void async_tx_clear_ack(struct dma_async_tx_descriptor *tx)
942 {
943 tx->flags &= ~DMA_CTRL_ACK;
944 }
945
async_tx_test_ack(struct dma_async_tx_descriptor * tx)946 static inline bool async_tx_test_ack(struct dma_async_tx_descriptor *tx)
947 {
948 return (tx->flags & DMA_CTRL_ACK) == DMA_CTRL_ACK;
949 }
950
951 #define dma_cap_set(tx, mask) __dma_cap_set((tx), &(mask))
952 static inline void
__dma_cap_set(enum dma_transaction_type tx_type,dma_cap_mask_t * dstp)953 __dma_cap_set(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp)
954 {
955 set_bit(tx_type, dstp->bits);
956 }
957
958 #define dma_cap_clear(tx, mask) __dma_cap_clear((tx), &(mask))
959 static inline void
__dma_cap_clear(enum dma_transaction_type tx_type,dma_cap_mask_t * dstp)960 __dma_cap_clear(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp)
961 {
962 clear_bit(tx_type, dstp->bits);
963 }
964
965 #define dma_cap_zero(mask) __dma_cap_zero(&(mask))
__dma_cap_zero(dma_cap_mask_t * dstp)966 static inline void __dma_cap_zero(dma_cap_mask_t *dstp)
967 {
968 bitmap_zero(dstp->bits, DMA_TX_TYPE_END);
969 }
970
971 #define dma_has_cap(tx, mask) __dma_has_cap((tx), &(mask))
972 static inline int
__dma_has_cap(enum dma_transaction_type tx_type,dma_cap_mask_t * srcp)973 __dma_has_cap(enum dma_transaction_type tx_type, dma_cap_mask_t *srcp)
974 {
975 return test_bit(tx_type, srcp->bits);
976 }
977
978 #define for_each_dma_cap_mask(cap, mask) \
979 for_each_set_bit(cap, mask.bits, DMA_TX_TYPE_END)
980
981 /**
982 * dma_async_issue_pending - flush pending transactions to HW
983 * @chan: target DMA channel
984 *
985 * This allows drivers to push copies to HW in batches,
986 * reducing MMIO writes where possible.
987 */
dma_async_issue_pending(struct dma_chan * chan)988 static inline void dma_async_issue_pending(struct dma_chan *chan)
989 {
990 chan->device->device_issue_pending(chan);
991 }
992
993 /**
994 * dma_async_is_tx_complete - poll for transaction completion
995 * @chan: DMA channel
996 * @cookie: transaction identifier to check status of
997 * @last: returns last completed cookie, can be NULL
998 * @used: returns last issued cookie, can be NULL
999 *
1000 * If @last and @used are passed in, upon return they reflect the driver
1001 * internal state and can be used with dma_async_is_complete() to check
1002 * the status of multiple cookies without re-checking hardware state.
1003 */
dma_async_is_tx_complete(struct dma_chan * chan,dma_cookie_t cookie,dma_cookie_t * last,dma_cookie_t * used)1004 static inline enum dma_status dma_async_is_tx_complete(struct dma_chan *chan,
1005 dma_cookie_t cookie, dma_cookie_t *last, dma_cookie_t *used)
1006 {
1007 struct dma_tx_state state;
1008 enum dma_status status;
1009
1010 status = chan->device->device_tx_status(chan, cookie, &state);
1011 if (last)
1012 *last = state.last;
1013 if (used)
1014 *used = state.used;
1015 return status;
1016 }
1017
1018 /**
1019 * dma_async_is_complete - test a cookie against chan state
1020 * @cookie: transaction identifier to test status of
1021 * @last_complete: last know completed transaction
1022 * @last_used: last cookie value handed out
1023 *
1024 * dma_async_is_complete() is used in dma_async_is_tx_complete()
1025 * the test logic is separated for lightweight testing of multiple cookies
1026 */
dma_async_is_complete(dma_cookie_t cookie,dma_cookie_t last_complete,dma_cookie_t last_used)1027 static inline enum dma_status dma_async_is_complete(dma_cookie_t cookie,
1028 dma_cookie_t last_complete, dma_cookie_t last_used)
1029 {
1030 if (last_complete <= last_used) {
1031 if ((cookie <= last_complete) || (cookie > last_used))
1032 return DMA_COMPLETE;
1033 } else {
1034 if ((cookie <= last_complete) && (cookie > last_used))
1035 return DMA_COMPLETE;
1036 }
1037 return DMA_IN_PROGRESS;
1038 }
1039
1040 static inline void
dma_set_tx_state(struct dma_tx_state * st,dma_cookie_t last,dma_cookie_t used,u32 residue)1041 dma_set_tx_state(struct dma_tx_state *st, dma_cookie_t last, dma_cookie_t used, u32 residue)
1042 {
1043 if (st) {
1044 st->last = last;
1045 st->used = used;
1046 st->residue = residue;
1047 }
1048 }
1049
1050 #ifdef CONFIG_DMA_ENGINE
1051 struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type);
1052 enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie);
1053 enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx);
1054 void dma_issue_pending_all(void);
1055 struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
1056 dma_filter_fn fn, void *fn_param);
1057 struct dma_chan *dma_request_slave_channel_reason(struct device *dev,
1058 const char *name);
1059 struct dma_chan *dma_request_slave_channel(struct device *dev, const char *name);
1060 void dma_release_channel(struct dma_chan *chan);
1061 #else
dma_find_channel(enum dma_transaction_type tx_type)1062 static inline struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type)
1063 {
1064 return NULL;
1065 }
dma_sync_wait(struct dma_chan * chan,dma_cookie_t cookie)1066 static inline enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie)
1067 {
1068 return DMA_COMPLETE;
1069 }
dma_wait_for_async_tx(struct dma_async_tx_descriptor * tx)1070 static inline enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
1071 {
1072 return DMA_COMPLETE;
1073 }
dma_issue_pending_all(void)1074 static inline void dma_issue_pending_all(void)
1075 {
1076 }
__dma_request_channel(const dma_cap_mask_t * mask,dma_filter_fn fn,void * fn_param)1077 static inline struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
1078 dma_filter_fn fn, void *fn_param)
1079 {
1080 return NULL;
1081 }
dma_request_slave_channel_reason(struct device * dev,const char * name)1082 static inline struct dma_chan *dma_request_slave_channel_reason(
1083 struct device *dev, const char *name)
1084 {
1085 return ERR_PTR(-ENODEV);
1086 }
dma_request_slave_channel(struct device * dev,const char * name)1087 static inline struct dma_chan *dma_request_slave_channel(struct device *dev,
1088 const char *name)
1089 {
1090 return NULL;
1091 }
dma_release_channel(struct dma_chan * chan)1092 static inline void dma_release_channel(struct dma_chan *chan)
1093 {
1094 }
1095 #endif
1096
1097 /* --- DMA device --- */
1098
1099 int dma_async_device_register(struct dma_device *device);
1100 void dma_async_device_unregister(struct dma_device *device);
1101 void dma_run_dependencies(struct dma_async_tx_descriptor *tx);
1102 struct dma_chan *dma_get_slave_channel(struct dma_chan *chan);
1103 struct dma_chan *dma_get_any_slave_channel(struct dma_device *device);
1104 struct dma_chan *net_dma_find_channel(void);
1105 #define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y)
1106 #define dma_request_slave_channel_compat(mask, x, y, dev, name) \
1107 __dma_request_slave_channel_compat(&(mask), x, y, dev, name)
1108
1109 static inline struct dma_chan
__dma_request_slave_channel_compat(const dma_cap_mask_t * mask,dma_filter_fn fn,void * fn_param,struct device * dev,char * name)1110 *__dma_request_slave_channel_compat(const dma_cap_mask_t *mask,
1111 dma_filter_fn fn, void *fn_param,
1112 struct device *dev, char *name)
1113 {
1114 struct dma_chan *chan;
1115
1116 chan = dma_request_slave_channel(dev, name);
1117 if (chan)
1118 return chan;
1119
1120 return __dma_request_channel(mask, fn, fn_param);
1121 }
1122
1123 /* --- Helper iov-locking functions --- */
1124
1125 struct dma_page_list {
1126 char __user *base_address;
1127 int nr_pages;
1128 struct page **pages;
1129 };
1130
1131 struct dma_pinned_list {
1132 int nr_iovecs;
1133 struct dma_page_list page_list[0];
1134 };
1135
1136 struct dma_pinned_list *dma_pin_iovec_pages(struct iovec *iov, size_t len);
1137 void dma_unpin_iovec_pages(struct dma_pinned_list* pinned_list);
1138
1139 dma_cookie_t dma_memcpy_to_iovec(struct dma_chan *chan, struct iovec *iov,
1140 struct dma_pinned_list *pinned_list, unsigned char *kdata, size_t len);
1141 dma_cookie_t dma_memcpy_pg_to_iovec(struct dma_chan *chan, struct iovec *iov,
1142 struct dma_pinned_list *pinned_list, struct page *page,
1143 unsigned int offset, size_t len);
1144
1145 #endif /* DMAENGINE_H */
1146