dmaengine.h 37 KB

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  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. #include <linux/device.h>
  24. #include <linux/err.h>
  25. #include <linux/uio.h>
  26. #include <linux/bug.h>
  27. #include <linux/scatterlist.h>
  28. #include <linux/bitmap.h>
  29. #include <linux/types.h>
  30. #include <asm/page.h>
  31. /**
  32. * typedef dma_cookie_t - an opaque DMA cookie
  33. *
  34. * if dma_cookie_t is >0 it's a DMA request cookie, <0 it's an error code
  35. */
  36. typedef s32 dma_cookie_t;
  37. #define DMA_MIN_COOKIE 1
  38. static inline int dma_submit_error(dma_cookie_t cookie)
  39. {
  40. return cookie < 0 ? cookie : 0;
  41. }
  42. /**
  43. * enum dma_status - DMA transaction status
  44. * @DMA_COMPLETE: transaction completed
  45. * @DMA_IN_PROGRESS: transaction not yet processed
  46. * @DMA_PAUSED: transaction is paused
  47. * @DMA_ERROR: transaction failed
  48. */
  49. enum dma_status {
  50. DMA_COMPLETE,
  51. DMA_IN_PROGRESS,
  52. DMA_PAUSED,
  53. DMA_ERROR,
  54. };
  55. /**
  56. * enum dma_transaction_type - DMA transaction types/indexes
  57. *
  58. * Note: The DMA_ASYNC_TX capability is not to be set by drivers. It is
  59. * automatically set as dma devices are registered.
  60. */
  61. enum dma_transaction_type {
  62. DMA_MEMCPY,
  63. DMA_XOR,
  64. DMA_PQ,
  65. DMA_XOR_VAL,
  66. DMA_PQ_VAL,
  67. DMA_INTERRUPT,
  68. DMA_SG,
  69. DMA_PRIVATE,
  70. DMA_ASYNC_TX,
  71. DMA_SLAVE,
  72. DMA_CYCLIC,
  73. DMA_INTERLEAVE,
  74. /* last transaction type for creation of the capabilities mask */
  75. DMA_TX_TYPE_END,
  76. };
  77. /**
  78. * enum dma_transfer_direction - dma transfer mode and direction indicator
  79. * @DMA_MEM_TO_MEM: Async/Memcpy mode
  80. * @DMA_MEM_TO_DEV: Slave mode & From Memory to Device
  81. * @DMA_DEV_TO_MEM: Slave mode & From Device to Memory
  82. * @DMA_DEV_TO_DEV: Slave mode & From Device to Device
  83. */
  84. enum dma_transfer_direction {
  85. DMA_MEM_TO_MEM,
  86. DMA_MEM_TO_DEV,
  87. DMA_DEV_TO_MEM,
  88. DMA_DEV_TO_DEV,
  89. DMA_TRANS_NONE,
  90. };
  91. /**
  92. * Interleaved Transfer Request
  93. * ----------------------------
  94. * A chunk is collection of contiguous bytes to be transfered.
  95. * The gap(in bytes) between two chunks is called inter-chunk-gap(ICG).
  96. * ICGs may or maynot change between chunks.
  97. * A FRAME is the smallest series of contiguous {chunk,icg} pairs,
  98. * that when repeated an integral number of times, specifies the transfer.
  99. * A transfer template is specification of a Frame, the number of times
  100. * it is to be repeated and other per-transfer attributes.
  101. *
  102. * Practically, a client driver would have ready a template for each
  103. * type of transfer it is going to need during its lifetime and
  104. * set only 'src_start' and 'dst_start' before submitting the requests.
  105. *
  106. *
  107. * | Frame-1 | Frame-2 | ~ | Frame-'numf' |
  108. * |====....==.===...=...|====....==.===...=...| ~ |====....==.===...=...|
  109. *
  110. * == Chunk size
  111. * ... ICG
  112. */
  113. /**
  114. * struct data_chunk - Element of scatter-gather list that makes a frame.
  115. * @size: Number of bytes to read from source.
  116. * size_dst := fn(op, size_src), so doesn't mean much for destination.
  117. * @icg: Number of bytes to jump after last src/dst address of this
  118. * chunk and before first src/dst address for next chunk.
  119. * Ignored for dst(assumed 0), if dst_inc is true and dst_sgl is false.
  120. * Ignored for src(assumed 0), if src_inc is true and src_sgl is false.
  121. */
  122. struct data_chunk {
  123. size_t size;
  124. size_t icg;
  125. };
  126. /**
  127. * struct dma_interleaved_template - Template to convey DMAC the transfer pattern
  128. * and attributes.
  129. * @src_start: Bus address of source for the first chunk.
  130. * @dst_start: Bus address of destination for the first chunk.
  131. * @dir: Specifies the type of Source and Destination.
  132. * @src_inc: If the source address increments after reading from it.
  133. * @dst_inc: If the destination address increments after writing to it.
  134. * @src_sgl: If the 'icg' of sgl[] applies to Source (scattered read).
  135. * Otherwise, source is read contiguously (icg ignored).
  136. * Ignored if src_inc is false.
  137. * @dst_sgl: If the 'icg' of sgl[] applies to Destination (scattered write).
  138. * Otherwise, destination is filled contiguously (icg ignored).
  139. * Ignored if dst_inc is false.
  140. * @numf: Number of frames in this template.
  141. * @frame_size: Number of chunks in a frame i.e, size of sgl[].
  142. * @sgl: Array of {chunk,icg} pairs that make up a frame.
  143. */
  144. struct dma_interleaved_template {
  145. dma_addr_t src_start;
  146. dma_addr_t dst_start;
  147. enum dma_transfer_direction dir;
  148. bool src_inc;
  149. bool dst_inc;
  150. bool src_sgl;
  151. bool dst_sgl;
  152. size_t numf;
  153. size_t frame_size;
  154. struct data_chunk sgl[0];
  155. };
  156. /**
  157. * enum dma_ctrl_flags - DMA flags to augment operation preparation,
  158. * control completion, and communicate status.
  159. * @DMA_PREP_INTERRUPT - trigger an interrupt (callback) upon completion of
  160. * this transaction
  161. * @DMA_CTRL_ACK - if clear, the descriptor cannot be reused until the client
  162. * acknowledges receipt, i.e. has has a chance to establish any dependency
  163. * chains
  164. * @DMA_PREP_PQ_DISABLE_P - prevent generation of P while generating Q
  165. * @DMA_PREP_PQ_DISABLE_Q - prevent generation of Q while generating P
  166. * @DMA_PREP_CONTINUE - indicate to a driver that it is reusing buffers as
  167. * sources that were the result of a previous operation, in the case of a PQ
  168. * operation it continues the calculation with new sources
  169. * @DMA_PREP_FENCE - tell the driver that subsequent operations depend
  170. * on the result of this operation
  171. */
  172. enum dma_ctrl_flags {
  173. DMA_PREP_INTERRUPT = (1 << 0),
  174. DMA_CTRL_ACK = (1 << 1),
  175. DMA_PREP_PQ_DISABLE_P = (1 << 2),
  176. DMA_PREP_PQ_DISABLE_Q = (1 << 3),
  177. DMA_PREP_CONTINUE = (1 << 4),
  178. DMA_PREP_FENCE = (1 << 5),
  179. };
  180. /**
  181. * enum sum_check_bits - bit position of pq_check_flags
  182. */
  183. enum sum_check_bits {
  184. SUM_CHECK_P = 0,
  185. SUM_CHECK_Q = 1,
  186. };
  187. /**
  188. * enum pq_check_flags - result of async_{xor,pq}_zero_sum operations
  189. * @SUM_CHECK_P_RESULT - 1 if xor zero sum error, 0 otherwise
  190. * @SUM_CHECK_Q_RESULT - 1 if reed-solomon zero sum error, 0 otherwise
  191. */
  192. enum sum_check_flags {
  193. SUM_CHECK_P_RESULT = (1 << SUM_CHECK_P),
  194. SUM_CHECK_Q_RESULT = (1 << SUM_CHECK_Q),
  195. };
  196. /**
  197. * dma_cap_mask_t - capabilities bitmap modeled after cpumask_t.
  198. * See linux/cpumask.h
  199. */
  200. typedef struct { DECLARE_BITMAP(bits, DMA_TX_TYPE_END); } dma_cap_mask_t;
  201. /**
  202. * struct dma_chan_percpu - the per-CPU part of struct dma_chan
  203. * @memcpy_count: transaction counter
  204. * @bytes_transferred: byte counter
  205. */
  206. struct dma_chan_percpu {
  207. /* stats */
  208. unsigned long memcpy_count;
  209. unsigned long bytes_transferred;
  210. };
  211. /**
  212. * struct dma_chan - devices supply DMA channels, clients use them
  213. * @device: ptr to the dma device who supplies this channel, always !%NULL
  214. * @cookie: last cookie value returned to client
  215. * @completed_cookie: last completed cookie for this channel
  216. * @chan_id: channel ID for sysfs
  217. * @dev: class device for sysfs
  218. * @device_node: used to add this to the device chan list
  219. * @local: per-cpu pointer to a struct dma_chan_percpu
  220. * @client_count: how many clients are using this channel
  221. * @table_count: number of appearances in the mem-to-mem allocation table
  222. * @private: private data for certain client-channel associations
  223. */
  224. struct dma_chan {
  225. struct dma_device *device;
  226. dma_cookie_t cookie;
  227. dma_cookie_t completed_cookie;
  228. /* sysfs */
  229. int chan_id;
  230. struct dma_chan_dev *dev;
  231. struct list_head device_node;
  232. struct dma_chan_percpu __percpu *local;
  233. int client_count;
  234. int table_count;
  235. void *private;
  236. };
  237. /**
  238. * struct dma_chan_dev - relate sysfs device node to backing channel device
  239. * @chan: driver channel device
  240. * @device: sysfs device
  241. * @dev_id: parent dma_device dev_id
  242. * @idr_ref: reference count to gate release of dma_device dev_id
  243. */
  244. struct dma_chan_dev {
  245. struct dma_chan *chan;
  246. struct device device;
  247. int dev_id;
  248. atomic_t *idr_ref;
  249. };
  250. /**
  251. * enum dma_slave_buswidth - defines bus width of the DMA slave
  252. * device, source or target buses
  253. */
  254. enum dma_slave_buswidth {
  255. DMA_SLAVE_BUSWIDTH_UNDEFINED = 0,
  256. DMA_SLAVE_BUSWIDTH_1_BYTE = 1,
  257. DMA_SLAVE_BUSWIDTH_2_BYTES = 2,
  258. DMA_SLAVE_BUSWIDTH_3_BYTES = 3,
  259. DMA_SLAVE_BUSWIDTH_4_BYTES = 4,
  260. DMA_SLAVE_BUSWIDTH_8_BYTES = 8,
  261. DMA_SLAVE_BUSWIDTH_16_BYTES = 16,
  262. DMA_SLAVE_BUSWIDTH_32_BYTES = 32,
  263. DMA_SLAVE_BUSWIDTH_64_BYTES = 64,
  264. };
  265. /**
  266. * struct dma_slave_config - dma slave channel runtime config
  267. * @direction: whether the data shall go in or out on this slave
  268. * channel, right now. DMA_MEM_TO_DEV and DMA_DEV_TO_MEM are
  269. * legal values. DEPRECATED, drivers should use the direction argument
  270. * to the device_prep_slave_sg and device_prep_dma_cyclic functions or
  271. * the dir field in the dma_interleaved_template structure.
  272. * @src_addr: this is the physical address where DMA slave data
  273. * should be read (RX), if the source is memory this argument is
  274. * ignored.
  275. * @dst_addr: this is the physical address where DMA slave data
  276. * should be written (TX), if the source is memory this argument
  277. * is ignored.
  278. * @src_addr_width: this is the width in bytes of the source (RX)
  279. * register where DMA data shall be read. If the source
  280. * is memory this may be ignored depending on architecture.
  281. * Legal values: 1, 2, 4, 8.
  282. * @dst_addr_width: same as src_addr_width but for destination
  283. * target (TX) mutatis mutandis.
  284. * @src_maxburst: the maximum number of words (note: words, as in
  285. * units of the src_addr_width member, not bytes) that can be sent
  286. * in one burst to the device. Typically something like half the
  287. * FIFO depth on I/O peripherals so you don't overflow it. This
  288. * may or may not be applicable on memory sources.
  289. * @dst_maxburst: same as src_maxburst but for destination target
  290. * mutatis mutandis.
  291. * @device_fc: Flow Controller Settings. Only valid for slave channels. Fill
  292. * with 'true' if peripheral should be flow controller. Direction will be
  293. * selected at Runtime.
  294. * @slave_id: Slave requester id. Only valid for slave channels. The dma
  295. * slave peripheral will have unique id as dma requester which need to be
  296. * pass as slave config.
  297. *
  298. * This struct is passed in as configuration data to a DMA engine
  299. * in order to set up a certain channel for DMA transport at runtime.
  300. * The DMA device/engine has to provide support for an additional
  301. * callback in the dma_device structure, device_config and this struct
  302. * will then be passed in as an argument to the function.
  303. *
  304. * The rationale for adding configuration information to this struct is as
  305. * follows: if it is likely that more than one DMA slave controllers in
  306. * the world will support the configuration option, then make it generic.
  307. * If not: if it is fixed so that it be sent in static from the platform
  308. * data, then prefer to do that.
  309. */
  310. struct dma_slave_config {
  311. enum dma_transfer_direction direction;
  312. dma_addr_t src_addr;
  313. dma_addr_t dst_addr;
  314. enum dma_slave_buswidth src_addr_width;
  315. enum dma_slave_buswidth dst_addr_width;
  316. u32 src_maxburst;
  317. u32 dst_maxburst;
  318. bool device_fc;
  319. unsigned int slave_id;
  320. };
  321. /**
  322. * enum dma_residue_granularity - Granularity of the reported transfer residue
  323. * @DMA_RESIDUE_GRANULARITY_DESCRIPTOR: Residue reporting is not support. The
  324. * DMA channel is only able to tell whether a descriptor has been completed or
  325. * not, which means residue reporting is not supported by this channel. The
  326. * residue field of the dma_tx_state field will always be 0.
  327. * @DMA_RESIDUE_GRANULARITY_SEGMENT: Residue is updated after each successfully
  328. * completed segment of the transfer (For cyclic transfers this is after each
  329. * period). This is typically implemented by having the hardware generate an
  330. * interrupt after each transferred segment and then the drivers updates the
  331. * outstanding residue by the size of the segment. Another possibility is if
  332. * the hardware supports scatter-gather and the segment descriptor has a field
  333. * which gets set after the segment has been completed. The driver then counts
  334. * the number of segments without the flag set to compute the residue.
  335. * @DMA_RESIDUE_GRANULARITY_BURST: Residue is updated after each transferred
  336. * burst. This is typically only supported if the hardware has a progress
  337. * register of some sort (E.g. a register with the current read/write address
  338. * or a register with the amount of bursts/beats/bytes that have been
  339. * transferred or still need to be transferred).
  340. */
  341. enum dma_residue_granularity {
  342. DMA_RESIDUE_GRANULARITY_DESCRIPTOR = 0,
  343. DMA_RESIDUE_GRANULARITY_SEGMENT = 1,
  344. DMA_RESIDUE_GRANULARITY_BURST = 2,
  345. };
  346. /* struct dma_slave_caps - expose capabilities of a slave channel only
  347. *
  348. * @src_addr_widths: bit mask of src addr widths the channel supports
  349. * @dst_addr_widths: bit mask of dstn addr widths the channel supports
  350. * @directions: bit mask of slave direction the channel supported
  351. * since the enum dma_transfer_direction is not defined as bits for each
  352. * type of direction, the dma controller should fill (1 << <TYPE>) and same
  353. * should be checked by controller as well
  354. * @cmd_pause: true, if pause and thereby resume is supported
  355. * @cmd_terminate: true, if terminate cmd is supported
  356. * @residue_granularity: granularity of the reported transfer residue
  357. */
  358. struct dma_slave_caps {
  359. u32 src_addr_widths;
  360. u32 dst_addr_widths;
  361. u32 directions;
  362. bool cmd_pause;
  363. bool cmd_terminate;
  364. enum dma_residue_granularity residue_granularity;
  365. };
  366. static inline const char *dma_chan_name(struct dma_chan *chan)
  367. {
  368. return dev_name(&chan->dev->device);
  369. }
  370. void dma_chan_cleanup(struct kref *kref);
  371. /**
  372. * typedef dma_filter_fn - callback filter for dma_request_channel
  373. * @chan: channel to be reviewed
  374. * @filter_param: opaque parameter passed through dma_request_channel
  375. *
  376. * When this optional parameter is specified in a call to dma_request_channel a
  377. * suitable channel is passed to this routine for further dispositioning before
  378. * being returned. Where 'suitable' indicates a non-busy channel that
  379. * satisfies the given capability mask. It returns 'true' to indicate that the
  380. * channel is suitable.
  381. */
  382. typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param);
  383. typedef void (*dma_async_tx_callback)(void *dma_async_param);
  384. struct dmaengine_unmap_data {
  385. u8 map_cnt;
  386. u8 to_cnt;
  387. u8 from_cnt;
  388. u8 bidi_cnt;
  389. struct device *dev;
  390. struct kref kref;
  391. size_t len;
  392. dma_addr_t addr[0];
  393. };
  394. /**
  395. * struct dma_async_tx_descriptor - async transaction descriptor
  396. * ---dma generic offload fields---
  397. * @cookie: tracking cookie for this transaction, set to -EBUSY if
  398. * this tx is sitting on a dependency list
  399. * @flags: flags to augment operation preparation, control completion, and
  400. * communicate status
  401. * @phys: physical address of the descriptor
  402. * @chan: target channel for this operation
  403. * @tx_submit: accept the descriptor, assign ordered cookie and mark the
  404. * descriptor pending. To be pushed on .issue_pending() call
  405. * @callback: routine to call after this operation is complete
  406. * @callback_param: general parameter to pass to the callback routine
  407. * ---async_tx api specific fields---
  408. * @next: at completion submit this descriptor
  409. * @parent: pointer to the next level up in the dependency chain
  410. * @lock: protect the parent and next pointers
  411. */
  412. struct dma_async_tx_descriptor {
  413. dma_cookie_t cookie;
  414. enum dma_ctrl_flags flags; /* not a 'long' to pack with cookie */
  415. dma_addr_t phys;
  416. struct dma_chan *chan;
  417. dma_cookie_t (*tx_submit)(struct dma_async_tx_descriptor *tx);
  418. dma_async_tx_callback callback;
  419. void *callback_param;
  420. struct dmaengine_unmap_data *unmap;
  421. #ifdef CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH
  422. struct dma_async_tx_descriptor *next;
  423. struct dma_async_tx_descriptor *parent;
  424. spinlock_t lock;
  425. #endif
  426. };
  427. #ifdef CONFIG_DMA_ENGINE
  428. static inline void dma_set_unmap(struct dma_async_tx_descriptor *tx,
  429. struct dmaengine_unmap_data *unmap)
  430. {
  431. kref_get(&unmap->kref);
  432. tx->unmap = unmap;
  433. }
  434. struct dmaengine_unmap_data *
  435. dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags);
  436. void dmaengine_unmap_put(struct dmaengine_unmap_data *unmap);
  437. #else
  438. static inline void dma_set_unmap(struct dma_async_tx_descriptor *tx,
  439. struct dmaengine_unmap_data *unmap)
  440. {
  441. }
  442. static inline struct dmaengine_unmap_data *
  443. dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags)
  444. {
  445. return NULL;
  446. }
  447. static inline void dmaengine_unmap_put(struct dmaengine_unmap_data *unmap)
  448. {
  449. }
  450. #endif
  451. static inline void dma_descriptor_unmap(struct dma_async_tx_descriptor *tx)
  452. {
  453. if (tx->unmap) {
  454. dmaengine_unmap_put(tx->unmap);
  455. tx->unmap = NULL;
  456. }
  457. }
  458. #ifndef CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH
  459. static inline void txd_lock(struct dma_async_tx_descriptor *txd)
  460. {
  461. }
  462. static inline void txd_unlock(struct dma_async_tx_descriptor *txd)
  463. {
  464. }
  465. static inline void txd_chain(struct dma_async_tx_descriptor *txd, struct dma_async_tx_descriptor *next)
  466. {
  467. BUG();
  468. }
  469. static inline void txd_clear_parent(struct dma_async_tx_descriptor *txd)
  470. {
  471. }
  472. static inline void txd_clear_next(struct dma_async_tx_descriptor *txd)
  473. {
  474. }
  475. static inline struct dma_async_tx_descriptor *txd_next(struct dma_async_tx_descriptor *txd)
  476. {
  477. return NULL;
  478. }
  479. static inline struct dma_async_tx_descriptor *txd_parent(struct dma_async_tx_descriptor *txd)
  480. {
  481. return NULL;
  482. }
  483. #else
  484. static inline void txd_lock(struct dma_async_tx_descriptor *txd)
  485. {
  486. spin_lock_bh(&txd->lock);
  487. }
  488. static inline void txd_unlock(struct dma_async_tx_descriptor *txd)
  489. {
  490. spin_unlock_bh(&txd->lock);
  491. }
  492. static inline void txd_chain(struct dma_async_tx_descriptor *txd, struct dma_async_tx_descriptor *next)
  493. {
  494. txd->next = next;
  495. next->parent = txd;
  496. }
  497. static inline void txd_clear_parent(struct dma_async_tx_descriptor *txd)
  498. {
  499. txd->parent = NULL;
  500. }
  501. static inline void txd_clear_next(struct dma_async_tx_descriptor *txd)
  502. {
  503. txd->next = NULL;
  504. }
  505. static inline struct dma_async_tx_descriptor *txd_parent(struct dma_async_tx_descriptor *txd)
  506. {
  507. return txd->parent;
  508. }
  509. static inline struct dma_async_tx_descriptor *txd_next(struct dma_async_tx_descriptor *txd)
  510. {
  511. return txd->next;
  512. }
  513. #endif
  514. /**
  515. * struct dma_tx_state - filled in to report the status of
  516. * a transfer.
  517. * @last: last completed DMA cookie
  518. * @used: last issued DMA cookie (i.e. the one in progress)
  519. * @residue: the remaining number of bytes left to transmit
  520. * on the selected transfer for states DMA_IN_PROGRESS and
  521. * DMA_PAUSED if this is implemented in the driver, else 0
  522. */
  523. struct dma_tx_state {
  524. dma_cookie_t last;
  525. dma_cookie_t used;
  526. u32 residue;
  527. };
  528. /**
  529. * struct dma_device - info on the entity supplying DMA services
  530. * @chancnt: how many DMA channels are supported
  531. * @privatecnt: how many DMA channels are requested by dma_request_channel
  532. * @channels: the list of struct dma_chan
  533. * @global_node: list_head for global dma_device_list
  534. * @cap_mask: one or more dma_capability flags
  535. * @max_xor: maximum number of xor sources, 0 if no capability
  536. * @max_pq: maximum number of PQ sources and PQ-continue capability
  537. * @copy_align: alignment shift for memcpy operations
  538. * @xor_align: alignment shift for xor operations
  539. * @pq_align: alignment shift for pq operations
  540. * @fill_align: alignment shift for memset operations
  541. * @dev_id: unique device ID
  542. * @dev: struct device reference for dma mapping api
  543. * @src_addr_widths: bit mask of src addr widths the device supports
  544. * @dst_addr_widths: bit mask of dst addr widths the device supports
  545. * @directions: bit mask of slave direction the device supports since
  546. * the enum dma_transfer_direction is not defined as bits for
  547. * each type of direction, the dma controller should fill (1 <<
  548. * <TYPE>) and same should be checked by controller as well
  549. * @residue_granularity: granularity of the transfer residue reported
  550. * by tx_status
  551. * @device_alloc_chan_resources: allocate resources and return the
  552. * number of allocated descriptors
  553. * @device_free_chan_resources: release DMA channel's resources
  554. * @device_prep_dma_memcpy: prepares a memcpy operation
  555. * @device_prep_dma_xor: prepares a xor operation
  556. * @device_prep_dma_xor_val: prepares a xor validation operation
  557. * @device_prep_dma_pq: prepares a pq operation
  558. * @device_prep_dma_pq_val: prepares a pqzero_sum operation
  559. * @device_prep_dma_interrupt: prepares an end of chain interrupt operation
  560. * @device_prep_slave_sg: prepares a slave dma operation
  561. * @device_prep_dma_cyclic: prepare a cyclic dma operation suitable for audio.
  562. * The function takes a buffer of size buf_len. The callback function will
  563. * be called after period_len bytes have been transferred.
  564. * @device_prep_interleaved_dma: Transfer expression in a generic way.
  565. * @device_config: Pushes a new configuration to a channel, return 0 or an error
  566. * code
  567. * @device_pause: Pauses any transfer happening on a channel. Returns
  568. * 0 or an error code
  569. * @device_resume: Resumes any transfer on a channel previously
  570. * paused. Returns 0 or an error code
  571. * @device_terminate_all: Aborts all transfers on a channel. Returns 0
  572. * or an error code
  573. * @device_tx_status: poll for transaction completion, the optional
  574. * txstate parameter can be supplied with a pointer to get a
  575. * struct with auxiliary transfer status information, otherwise the call
  576. * will just return a simple status code
  577. * @device_issue_pending: push pending transactions to hardware
  578. */
  579. struct dma_device {
  580. unsigned int chancnt;
  581. unsigned int privatecnt;
  582. struct list_head channels;
  583. struct list_head global_node;
  584. dma_cap_mask_t cap_mask;
  585. unsigned short max_xor;
  586. unsigned short max_pq;
  587. u8 copy_align;
  588. u8 xor_align;
  589. u8 pq_align;
  590. u8 fill_align;
  591. #define DMA_HAS_PQ_CONTINUE (1 << 15)
  592. int dev_id;
  593. struct device *dev;
  594. u32 src_addr_widths;
  595. u32 dst_addr_widths;
  596. u32 directions;
  597. enum dma_residue_granularity residue_granularity;
  598. int (*device_alloc_chan_resources)(struct dma_chan *chan);
  599. void (*device_free_chan_resources)(struct dma_chan *chan);
  600. struct dma_async_tx_descriptor *(*device_prep_dma_memcpy)(
  601. struct dma_chan *chan, dma_addr_t dst, dma_addr_t src,
  602. size_t len, unsigned long flags);
  603. struct dma_async_tx_descriptor *(*device_prep_dma_xor)(
  604. struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src,
  605. unsigned int src_cnt, size_t len, unsigned long flags);
  606. struct dma_async_tx_descriptor *(*device_prep_dma_xor_val)(
  607. struct dma_chan *chan, dma_addr_t *src, unsigned int src_cnt,
  608. size_t len, enum sum_check_flags *result, unsigned long flags);
  609. struct dma_async_tx_descriptor *(*device_prep_dma_pq)(
  610. struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
  611. unsigned int src_cnt, const unsigned char *scf,
  612. size_t len, unsigned long flags);
  613. struct dma_async_tx_descriptor *(*device_prep_dma_pq_val)(
  614. struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
  615. unsigned int src_cnt, const unsigned char *scf, size_t len,
  616. enum sum_check_flags *pqres, unsigned long flags);
  617. struct dma_async_tx_descriptor *(*device_prep_dma_interrupt)(
  618. struct dma_chan *chan, unsigned long flags);
  619. struct dma_async_tx_descriptor *(*device_prep_dma_sg)(
  620. struct dma_chan *chan,
  621. struct scatterlist *dst_sg, unsigned int dst_nents,
  622. struct scatterlist *src_sg, unsigned int src_nents,
  623. unsigned long flags);
  624. struct dma_async_tx_descriptor *(*device_prep_slave_sg)(
  625. struct dma_chan *chan, struct scatterlist *sgl,
  626. unsigned int sg_len, enum dma_transfer_direction direction,
  627. unsigned long flags, void *context);
  628. struct dma_async_tx_descriptor *(*device_prep_dma_cyclic)(
  629. struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
  630. size_t period_len, enum dma_transfer_direction direction,
  631. unsigned long flags);
  632. struct dma_async_tx_descriptor *(*device_prep_interleaved_dma)(
  633. struct dma_chan *chan, struct dma_interleaved_template *xt,
  634. unsigned long flags);
  635. int (*device_config)(struct dma_chan *chan,
  636. struct dma_slave_config *config);
  637. int (*device_pause)(struct dma_chan *chan);
  638. int (*device_resume)(struct dma_chan *chan);
  639. int (*device_terminate_all)(struct dma_chan *chan);
  640. enum dma_status (*device_tx_status)(struct dma_chan *chan,
  641. dma_cookie_t cookie,
  642. struct dma_tx_state *txstate);
  643. void (*device_issue_pending)(struct dma_chan *chan);
  644. };
  645. static inline int dmaengine_slave_config(struct dma_chan *chan,
  646. struct dma_slave_config *config)
  647. {
  648. if (chan->device->device_config)
  649. return chan->device->device_config(chan, config);
  650. return -ENOSYS;
  651. }
  652. static inline bool is_slave_direction(enum dma_transfer_direction direction)
  653. {
  654. return (direction == DMA_MEM_TO_DEV) || (direction == DMA_DEV_TO_MEM);
  655. }
  656. static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_single(
  657. struct dma_chan *chan, dma_addr_t buf, size_t len,
  658. enum dma_transfer_direction dir, unsigned long flags)
  659. {
  660. struct scatterlist sg;
  661. sg_init_table(&sg, 1);
  662. sg_dma_address(&sg) = buf;
  663. sg_dma_len(&sg) = len;
  664. return chan->device->device_prep_slave_sg(chan, &sg, 1,
  665. dir, flags, NULL);
  666. }
  667. static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_sg(
  668. struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len,
  669. enum dma_transfer_direction dir, unsigned long flags)
  670. {
  671. return chan->device->device_prep_slave_sg(chan, sgl, sg_len,
  672. dir, flags, NULL);
  673. }
  674. #ifdef CONFIG_RAPIDIO_DMA_ENGINE
  675. struct rio_dma_ext;
  676. static inline struct dma_async_tx_descriptor *dmaengine_prep_rio_sg(
  677. struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len,
  678. enum dma_transfer_direction dir, unsigned long flags,
  679. struct rio_dma_ext *rio_ext)
  680. {
  681. return chan->device->device_prep_slave_sg(chan, sgl, sg_len,
  682. dir, flags, rio_ext);
  683. }
  684. #endif
  685. static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_cyclic(
  686. struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
  687. size_t period_len, enum dma_transfer_direction dir,
  688. unsigned long flags)
  689. {
  690. return chan->device->device_prep_dma_cyclic(chan, buf_addr, buf_len,
  691. period_len, dir, flags);
  692. }
  693. static inline struct dma_async_tx_descriptor *dmaengine_prep_interleaved_dma(
  694. struct dma_chan *chan, struct dma_interleaved_template *xt,
  695. unsigned long flags)
  696. {
  697. return chan->device->device_prep_interleaved_dma(chan, xt, flags);
  698. }
  699. static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_sg(
  700. struct dma_chan *chan,
  701. struct scatterlist *dst_sg, unsigned int dst_nents,
  702. struct scatterlist *src_sg, unsigned int src_nents,
  703. unsigned long flags)
  704. {
  705. return chan->device->device_prep_dma_sg(chan, dst_sg, dst_nents,
  706. src_sg, src_nents, flags);
  707. }
  708. static inline int dmaengine_terminate_all(struct dma_chan *chan)
  709. {
  710. if (chan->device->device_terminate_all)
  711. return chan->device->device_terminate_all(chan);
  712. return -ENOSYS;
  713. }
  714. static inline int dmaengine_pause(struct dma_chan *chan)
  715. {
  716. if (chan->device->device_pause)
  717. return chan->device->device_pause(chan);
  718. return -ENOSYS;
  719. }
  720. static inline int dmaengine_resume(struct dma_chan *chan)
  721. {
  722. if (chan->device->device_resume)
  723. return chan->device->device_resume(chan);
  724. return -ENOSYS;
  725. }
  726. static inline enum dma_status dmaengine_tx_status(struct dma_chan *chan,
  727. dma_cookie_t cookie, struct dma_tx_state *state)
  728. {
  729. return chan->device->device_tx_status(chan, cookie, state);
  730. }
  731. static inline dma_cookie_t dmaengine_submit(struct dma_async_tx_descriptor *desc)
  732. {
  733. return desc->tx_submit(desc);
  734. }
  735. static inline bool dmaengine_check_align(u8 align, size_t off1, size_t off2, size_t len)
  736. {
  737. size_t mask;
  738. if (!align)
  739. return true;
  740. mask = (1 << align) - 1;
  741. if (mask & (off1 | off2 | len))
  742. return false;
  743. return true;
  744. }
  745. static inline bool is_dma_copy_aligned(struct dma_device *dev, size_t off1,
  746. size_t off2, size_t len)
  747. {
  748. return dmaengine_check_align(dev->copy_align, off1, off2, len);
  749. }
  750. static inline bool is_dma_xor_aligned(struct dma_device *dev, size_t off1,
  751. size_t off2, size_t len)
  752. {
  753. return dmaengine_check_align(dev->xor_align, off1, off2, len);
  754. }
  755. static inline bool is_dma_pq_aligned(struct dma_device *dev, size_t off1,
  756. size_t off2, size_t len)
  757. {
  758. return dmaengine_check_align(dev->pq_align, off1, off2, len);
  759. }
  760. static inline bool is_dma_fill_aligned(struct dma_device *dev, size_t off1,
  761. size_t off2, size_t len)
  762. {
  763. return dmaengine_check_align(dev->fill_align, off1, off2, len);
  764. }
  765. static inline void
  766. dma_set_maxpq(struct dma_device *dma, int maxpq, int has_pq_continue)
  767. {
  768. dma->max_pq = maxpq;
  769. if (has_pq_continue)
  770. dma->max_pq |= DMA_HAS_PQ_CONTINUE;
  771. }
  772. static inline bool dmaf_continue(enum dma_ctrl_flags flags)
  773. {
  774. return (flags & DMA_PREP_CONTINUE) == DMA_PREP_CONTINUE;
  775. }
  776. static inline bool dmaf_p_disabled_continue(enum dma_ctrl_flags flags)
  777. {
  778. enum dma_ctrl_flags mask = DMA_PREP_CONTINUE | DMA_PREP_PQ_DISABLE_P;
  779. return (flags & mask) == mask;
  780. }
  781. static inline bool dma_dev_has_pq_continue(struct dma_device *dma)
  782. {
  783. return (dma->max_pq & DMA_HAS_PQ_CONTINUE) == DMA_HAS_PQ_CONTINUE;
  784. }
  785. static inline unsigned short dma_dev_to_maxpq(struct dma_device *dma)
  786. {
  787. return dma->max_pq & ~DMA_HAS_PQ_CONTINUE;
  788. }
  789. /* dma_maxpq - reduce maxpq in the face of continued operations
  790. * @dma - dma device with PQ capability
  791. * @flags - to check if DMA_PREP_CONTINUE and DMA_PREP_PQ_DISABLE_P are set
  792. *
  793. * When an engine does not support native continuation we need 3 extra
  794. * source slots to reuse P and Q with the following coefficients:
  795. * 1/ {00} * P : remove P from Q', but use it as a source for P'
  796. * 2/ {01} * Q : use Q to continue Q' calculation
  797. * 3/ {00} * Q : subtract Q from P' to cancel (2)
  798. *
  799. * In the case where P is disabled we only need 1 extra source:
  800. * 1/ {01} * Q : use Q to continue Q' calculation
  801. */
  802. static inline int dma_maxpq(struct dma_device *dma, enum dma_ctrl_flags flags)
  803. {
  804. if (dma_dev_has_pq_continue(dma) || !dmaf_continue(flags))
  805. return dma_dev_to_maxpq(dma);
  806. else if (dmaf_p_disabled_continue(flags))
  807. return dma_dev_to_maxpq(dma) - 1;
  808. else if (dmaf_continue(flags))
  809. return dma_dev_to_maxpq(dma) - 3;
  810. BUG();
  811. }
  812. /* --- public DMA engine API --- */
  813. #ifdef CONFIG_DMA_ENGINE
  814. void dmaengine_get(void);
  815. void dmaengine_put(void);
  816. #else
  817. static inline void dmaengine_get(void)
  818. {
  819. }
  820. static inline void dmaengine_put(void)
  821. {
  822. }
  823. #endif
  824. #ifdef CONFIG_ASYNC_TX_DMA
  825. #define async_dmaengine_get() dmaengine_get()
  826. #define async_dmaengine_put() dmaengine_put()
  827. #ifndef CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH
  828. #define async_dma_find_channel(type) dma_find_channel(DMA_ASYNC_TX)
  829. #else
  830. #define async_dma_find_channel(type) dma_find_channel(type)
  831. #endif /* CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH */
  832. #else
  833. static inline void async_dmaengine_get(void)
  834. {
  835. }
  836. static inline void async_dmaengine_put(void)
  837. {
  838. }
  839. static inline struct dma_chan *
  840. async_dma_find_channel(enum dma_transaction_type type)
  841. {
  842. return NULL;
  843. }
  844. #endif /* CONFIG_ASYNC_TX_DMA */
  845. void dma_async_tx_descriptor_init(struct dma_async_tx_descriptor *tx,
  846. struct dma_chan *chan);
  847. static inline void async_tx_ack(struct dma_async_tx_descriptor *tx)
  848. {
  849. tx->flags |= DMA_CTRL_ACK;
  850. }
  851. static inline void async_tx_clear_ack(struct dma_async_tx_descriptor *tx)
  852. {
  853. tx->flags &= ~DMA_CTRL_ACK;
  854. }
  855. static inline bool async_tx_test_ack(struct dma_async_tx_descriptor *tx)
  856. {
  857. return (tx->flags & DMA_CTRL_ACK) == DMA_CTRL_ACK;
  858. }
  859. #define dma_cap_set(tx, mask) __dma_cap_set((tx), &(mask))
  860. static inline void
  861. __dma_cap_set(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp)
  862. {
  863. set_bit(tx_type, dstp->bits);
  864. }
  865. #define dma_cap_clear(tx, mask) __dma_cap_clear((tx), &(mask))
  866. static inline void
  867. __dma_cap_clear(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp)
  868. {
  869. clear_bit(tx_type, dstp->bits);
  870. }
  871. #define dma_cap_zero(mask) __dma_cap_zero(&(mask))
  872. static inline void __dma_cap_zero(dma_cap_mask_t *dstp)
  873. {
  874. bitmap_zero(dstp->bits, DMA_TX_TYPE_END);
  875. }
  876. #define dma_has_cap(tx, mask) __dma_has_cap((tx), &(mask))
  877. static inline int
  878. __dma_has_cap(enum dma_transaction_type tx_type, dma_cap_mask_t *srcp)
  879. {
  880. return test_bit(tx_type, srcp->bits);
  881. }
  882. #define for_each_dma_cap_mask(cap, mask) \
  883. for_each_set_bit(cap, mask.bits, DMA_TX_TYPE_END)
  884. /**
  885. * dma_async_issue_pending - flush pending transactions to HW
  886. * @chan: target DMA channel
  887. *
  888. * This allows drivers to push copies to HW in batches,
  889. * reducing MMIO writes where possible.
  890. */
  891. static inline void dma_async_issue_pending(struct dma_chan *chan)
  892. {
  893. chan->device->device_issue_pending(chan);
  894. }
  895. /**
  896. * dma_async_is_tx_complete - poll for transaction completion
  897. * @chan: DMA channel
  898. * @cookie: transaction identifier to check status of
  899. * @last: returns last completed cookie, can be NULL
  900. * @used: returns last issued cookie, can be NULL
  901. *
  902. * If @last and @used are passed in, upon return they reflect the driver
  903. * internal state and can be used with dma_async_is_complete() to check
  904. * the status of multiple cookies without re-checking hardware state.
  905. */
  906. static inline enum dma_status dma_async_is_tx_complete(struct dma_chan *chan,
  907. dma_cookie_t cookie, dma_cookie_t *last, dma_cookie_t *used)
  908. {
  909. struct dma_tx_state state;
  910. enum dma_status status;
  911. status = chan->device->device_tx_status(chan, cookie, &state);
  912. if (last)
  913. *last = state.last;
  914. if (used)
  915. *used = state.used;
  916. return status;
  917. }
  918. /**
  919. * dma_async_is_complete - test a cookie against chan state
  920. * @cookie: transaction identifier to test status of
  921. * @last_complete: last know completed transaction
  922. * @last_used: last cookie value handed out
  923. *
  924. * dma_async_is_complete() is used in dma_async_is_tx_complete()
  925. * the test logic is separated for lightweight testing of multiple cookies
  926. */
  927. static inline enum dma_status dma_async_is_complete(dma_cookie_t cookie,
  928. dma_cookie_t last_complete, dma_cookie_t last_used)
  929. {
  930. if (last_complete <= last_used) {
  931. if ((cookie <= last_complete) || (cookie > last_used))
  932. return DMA_COMPLETE;
  933. } else {
  934. if ((cookie <= last_complete) && (cookie > last_used))
  935. return DMA_COMPLETE;
  936. }
  937. return DMA_IN_PROGRESS;
  938. }
  939. static inline void
  940. dma_set_tx_state(struct dma_tx_state *st, dma_cookie_t last, dma_cookie_t used, u32 residue)
  941. {
  942. if (st) {
  943. st->last = last;
  944. st->used = used;
  945. st->residue = residue;
  946. }
  947. }
  948. #ifdef CONFIG_DMA_ENGINE
  949. struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type);
  950. enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie);
  951. enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx);
  952. void dma_issue_pending_all(void);
  953. struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
  954. dma_filter_fn fn, void *fn_param);
  955. struct dma_chan *dma_request_slave_channel_reason(struct device *dev,
  956. const char *name);
  957. struct dma_chan *dma_request_slave_channel(struct device *dev, const char *name);
  958. void dma_release_channel(struct dma_chan *chan);
  959. int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps);
  960. #else
  961. static inline struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type)
  962. {
  963. return NULL;
  964. }
  965. static inline enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie)
  966. {
  967. return DMA_COMPLETE;
  968. }
  969. static inline enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
  970. {
  971. return DMA_COMPLETE;
  972. }
  973. static inline void dma_issue_pending_all(void)
  974. {
  975. }
  976. static inline struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
  977. dma_filter_fn fn, void *fn_param)
  978. {
  979. return NULL;
  980. }
  981. static inline struct dma_chan *dma_request_slave_channel_reason(
  982. struct device *dev, const char *name)
  983. {
  984. return ERR_PTR(-ENODEV);
  985. }
  986. static inline struct dma_chan *dma_request_slave_channel(struct device *dev,
  987. const char *name)
  988. {
  989. return NULL;
  990. }
  991. static inline void dma_release_channel(struct dma_chan *chan)
  992. {
  993. }
  994. static inline int dma_get_slave_caps(struct dma_chan *chan,
  995. struct dma_slave_caps *caps)
  996. {
  997. return -ENXIO;
  998. }
  999. #endif
  1000. /* --- DMA device --- */
  1001. int dma_async_device_register(struct dma_device *device);
  1002. void dma_async_device_unregister(struct dma_device *device);
  1003. void dma_run_dependencies(struct dma_async_tx_descriptor *tx);
  1004. struct dma_chan *dma_get_slave_channel(struct dma_chan *chan);
  1005. struct dma_chan *dma_get_any_slave_channel(struct dma_device *device);
  1006. struct dma_chan *net_dma_find_channel(void);
  1007. #define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y)
  1008. #define dma_request_slave_channel_compat(mask, x, y, dev, name) \
  1009. __dma_request_slave_channel_compat(&(mask), x, y, dev, name)
  1010. static inline struct dma_chan
  1011. *__dma_request_slave_channel_compat(const dma_cap_mask_t *mask,
  1012. dma_filter_fn fn, void *fn_param,
  1013. struct device *dev, char *name)
  1014. {
  1015. struct dma_chan *chan;
  1016. chan = dma_request_slave_channel(dev, name);
  1017. if (chan)
  1018. return chan;
  1019. return __dma_request_channel(mask, fn, fn_param);
  1020. }
  1021. /* --- Helper iov-locking functions --- */
  1022. struct dma_page_list {
  1023. char __user *base_address;
  1024. int nr_pages;
  1025. struct page **pages;
  1026. };
  1027. struct dma_pinned_list {
  1028. int nr_iovecs;
  1029. struct dma_page_list page_list[0];
  1030. };
  1031. struct dma_pinned_list *dma_pin_iovec_pages(struct iovec *iov, size_t len);
  1032. void dma_unpin_iovec_pages(struct dma_pinned_list* pinned_list);
  1033. dma_cookie_t dma_memcpy_to_iovec(struct dma_chan *chan, struct iovec *iov,
  1034. struct dma_pinned_list *pinned_list, unsigned char *kdata, size_t len);
  1035. dma_cookie_t dma_memcpy_pg_to_iovec(struct dma_chan *chan, struct iovec *iov,
  1036. struct dma_pinned_list *pinned_list, struct page *page,
  1037. unsigned int offset, size_t len);
  1038. #endif /* DMAENGINE_H */