ff50ff4c6a57148c3a015a6ba3ebb1c81f69c6f8
[linux-drm-fsl-dcu.git] / drivers / dma / edma.c
1 /*
2  * TI EDMA DMA engine driver
3  *
4  * Copyright 2012 Texas Instruments
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation version 2.
9  *
10  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
11  * kind, whether express or implied; without even the implied warranty
12  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  */
15
16 #include <linux/dmaengine.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/err.h>
19 #include <linux/init.h>
20 #include <linux/interrupt.h>
21 #include <linux/list.h>
22 #include <linux/module.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 #include <linux/spinlock.h>
26
27 #include <linux/platform_data/edma.h>
28
29 #include "dmaengine.h"
30 #include "virt-dma.h"
31
32 /*
33  * This will go away when the private EDMA API is folded
34  * into this driver and the platform device(s) are
35  * instantiated in the arch code. We can only get away
36  * with this simplification because DA8XX may not be built
37  * in the same kernel image with other DaVinci parts. This
38  * avoids having to sprinkle dmaengine driver platform devices
39  * and data throughout all the existing board files.
40  */
41 #ifdef CONFIG_ARCH_DAVINCI_DA8XX
42 #define EDMA_CTLRS      2
43 #define EDMA_CHANS      32
44 #else
45 #define EDMA_CTLRS      1
46 #define EDMA_CHANS      64
47 #endif /* CONFIG_ARCH_DAVINCI_DA8XX */
48
49 /* Max of 16 segments per channel to conserve PaRAM slots */
50 #define MAX_NR_SG               16
51 #define EDMA_MAX_SLOTS          MAX_NR_SG
52 #define EDMA_DESCRIPTORS        16
53
54 struct edma_desc {
55         struct virt_dma_desc            vdesc;
56         struct list_head                node;
57         int                             absync;
58         int                             pset_nr;
59         int                             processed;
60         struct edmacc_param             pset[0];
61 };
62
63 struct edma_cc;
64
65 struct edma_chan {
66         struct virt_dma_chan            vchan;
67         struct list_head                node;
68         struct edma_desc                *edesc;
69         struct edma_cc                  *ecc;
70         int                             ch_num;
71         bool                            alloced;
72         int                             slot[EDMA_MAX_SLOTS];
73         int                             missed;
74         struct dma_slave_config         cfg;
75 };
76
77 struct edma_cc {
78         int                             ctlr;
79         struct dma_device               dma_slave;
80         struct edma_chan                slave_chans[EDMA_CHANS];
81         int                             num_slave_chans;
82         int                             dummy_slot;
83 };
84
85 static inline struct edma_cc *to_edma_cc(struct dma_device *d)
86 {
87         return container_of(d, struct edma_cc, dma_slave);
88 }
89
90 static inline struct edma_chan *to_edma_chan(struct dma_chan *c)
91 {
92         return container_of(c, struct edma_chan, vchan.chan);
93 }
94
95 static inline struct edma_desc
96 *to_edma_desc(struct dma_async_tx_descriptor *tx)
97 {
98         return container_of(tx, struct edma_desc, vdesc.tx);
99 }
100
101 static void edma_desc_free(struct virt_dma_desc *vdesc)
102 {
103         kfree(container_of(vdesc, struct edma_desc, vdesc));
104 }
105
106 /* Dispatch a queued descriptor to the controller (caller holds lock) */
107 static void edma_execute(struct edma_chan *echan)
108 {
109         struct virt_dma_desc *vdesc;
110         struct edma_desc *edesc;
111         struct device *dev = echan->vchan.chan.device->dev;
112         int i, j, left, nslots;
113
114         /* If either we processed all psets or we're still not started */
115         if (!echan->edesc ||
116             echan->edesc->pset_nr == echan->edesc->processed) {
117                 /* Get next vdesc */
118                 vdesc = vchan_next_desc(&echan->vchan);
119                 if (!vdesc) {
120                         echan->edesc = NULL;
121                         return;
122                 }
123                 list_del(&vdesc->node);
124                 echan->edesc = to_edma_desc(&vdesc->tx);
125         }
126
127         edesc = echan->edesc;
128
129         /* Find out how many left */
130         left = edesc->pset_nr - edesc->processed;
131         nslots = min(MAX_NR_SG, left);
132
133         /* Write descriptor PaRAM set(s) */
134         for (i = 0; i < nslots; i++) {
135                 j = i + edesc->processed;
136                 edma_write_slot(echan->slot[i], &edesc->pset[j]);
137                 dev_dbg(echan->vchan.chan.device->dev,
138                         "\n pset[%d]:\n"
139                         "  chnum\t%d\n"
140                         "  slot\t%d\n"
141                         "  opt\t%08x\n"
142                         "  src\t%08x\n"
143                         "  dst\t%08x\n"
144                         "  abcnt\t%08x\n"
145                         "  ccnt\t%08x\n"
146                         "  bidx\t%08x\n"
147                         "  cidx\t%08x\n"
148                         "  lkrld\t%08x\n",
149                         j, echan->ch_num, echan->slot[i],
150                         edesc->pset[j].opt,
151                         edesc->pset[j].src,
152                         edesc->pset[j].dst,
153                         edesc->pset[j].a_b_cnt,
154                         edesc->pset[j].ccnt,
155                         edesc->pset[j].src_dst_bidx,
156                         edesc->pset[j].src_dst_cidx,
157                         edesc->pset[j].link_bcntrld);
158                 /* Link to the previous slot if not the last set */
159                 if (i != (nslots - 1))
160                         edma_link(echan->slot[i], echan->slot[i+1]);
161         }
162
163         edesc->processed += nslots;
164
165         /*
166          * If this is either the last set in a set of SG-list transactions
167          * then setup a link to the dummy slot, this results in all future
168          * events being absorbed and that's OK because we're done
169          */
170         if (edesc->processed == edesc->pset_nr)
171                 edma_link(echan->slot[nslots-1], echan->ecc->dummy_slot);
172
173         edma_resume(echan->ch_num);
174
175         if (edesc->processed <= MAX_NR_SG) {
176                 dev_dbg(dev, "first transfer starting %d\n", echan->ch_num);
177                 edma_start(echan->ch_num);
178         }
179
180         /*
181          * This happens due to setup times between intermediate transfers
182          * in long SG lists which have to be broken up into transfers of
183          * MAX_NR_SG
184          */
185         if (echan->missed) {
186                 dev_dbg(dev, "missed event in execute detected\n");
187                 edma_clean_channel(echan->ch_num);
188                 edma_stop(echan->ch_num);
189                 edma_start(echan->ch_num);
190                 edma_trigger_channel(echan->ch_num);
191                 echan->missed = 0;
192         }
193 }
194
195 static int edma_terminate_all(struct edma_chan *echan)
196 {
197         unsigned long flags;
198         LIST_HEAD(head);
199
200         spin_lock_irqsave(&echan->vchan.lock, flags);
201
202         /*
203          * Stop DMA activity: we assume the callback will not be called
204          * after edma_dma() returns (even if it does, it will see
205          * echan->edesc is NULL and exit.)
206          */
207         if (echan->edesc) {
208                 echan->edesc = NULL;
209                 edma_stop(echan->ch_num);
210         }
211
212         vchan_get_all_descriptors(&echan->vchan, &head);
213         spin_unlock_irqrestore(&echan->vchan.lock, flags);
214         vchan_dma_desc_free_list(&echan->vchan, &head);
215
216         return 0;
217 }
218
219 static int edma_slave_config(struct edma_chan *echan,
220         struct dma_slave_config *cfg)
221 {
222         if (cfg->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES ||
223             cfg->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)
224                 return -EINVAL;
225
226         memcpy(&echan->cfg, cfg, sizeof(echan->cfg));
227
228         return 0;
229 }
230
231 static int edma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
232                         unsigned long arg)
233 {
234         int ret = 0;
235         struct dma_slave_config *config;
236         struct edma_chan *echan = to_edma_chan(chan);
237
238         switch (cmd) {
239         case DMA_TERMINATE_ALL:
240                 edma_terminate_all(echan);
241                 break;
242         case DMA_SLAVE_CONFIG:
243                 config = (struct dma_slave_config *)arg;
244                 ret = edma_slave_config(echan, config);
245                 break;
246         default:
247                 ret = -ENOSYS;
248         }
249
250         return ret;
251 }
252
253 static struct dma_async_tx_descriptor *edma_prep_slave_sg(
254         struct dma_chan *chan, struct scatterlist *sgl,
255         unsigned int sg_len, enum dma_transfer_direction direction,
256         unsigned long tx_flags, void *context)
257 {
258         struct edma_chan *echan = to_edma_chan(chan);
259         struct device *dev = chan->device->dev;
260         struct edma_desc *edesc;
261         dma_addr_t dev_addr;
262         enum dma_slave_buswidth dev_width;
263         u32 burst;
264         struct scatterlist *sg;
265         int acnt, bcnt, ccnt, src, dst, cidx;
266         int src_bidx, dst_bidx, src_cidx, dst_cidx;
267         int i, nslots;
268
269         if (unlikely(!echan || !sgl || !sg_len))
270                 return NULL;
271
272         if (direction == DMA_DEV_TO_MEM) {
273                 dev_addr = echan->cfg.src_addr;
274                 dev_width = echan->cfg.src_addr_width;
275                 burst = echan->cfg.src_maxburst;
276         } else if (direction == DMA_MEM_TO_DEV) {
277                 dev_addr = echan->cfg.dst_addr;
278                 dev_width = echan->cfg.dst_addr_width;
279                 burst = echan->cfg.dst_maxburst;
280         } else {
281                 dev_err(dev, "%s: bad direction?\n", __func__);
282                 return NULL;
283         }
284
285         if (dev_width == DMA_SLAVE_BUSWIDTH_UNDEFINED) {
286                 dev_err(dev, "Undefined slave buswidth\n");
287                 return NULL;
288         }
289
290         edesc = kzalloc(sizeof(*edesc) + sg_len *
291                 sizeof(edesc->pset[0]), GFP_ATOMIC);
292         if (!edesc) {
293                 dev_dbg(dev, "Failed to allocate a descriptor\n");
294                 return NULL;
295         }
296
297         edesc->pset_nr = sg_len;
298
299         /* Allocate a PaRAM slot, if needed */
300         nslots = min_t(unsigned, MAX_NR_SG, sg_len);
301
302         for (i = 0; i < nslots; i++) {
303                 if (echan->slot[i] < 0) {
304                         echan->slot[i] =
305                                 edma_alloc_slot(EDMA_CTLR(echan->ch_num),
306                                                 EDMA_SLOT_ANY);
307                         if (echan->slot[i] < 0) {
308                                 dev_err(dev, "Failed to allocate slot\n");
309                                 return NULL;
310                         }
311                 }
312         }
313
314         /* Configure PaRAM sets for each SG */
315         for_each_sg(sgl, sg, sg_len, i) {
316
317                 acnt = dev_width;
318
319                 /*
320                  * If the maxburst is equal to the fifo width, use
321                  * A-synced transfers. This allows for large contiguous
322                  * buffer transfers using only one PaRAM set.
323                  */
324                 if (burst == 1) {
325                         edesc->absync = false;
326                         ccnt = sg_dma_len(sg) / acnt / (SZ_64K - 1);
327                         bcnt = sg_dma_len(sg) / acnt - ccnt * (SZ_64K - 1);
328                         if (bcnt)
329                                 ccnt++;
330                         else
331                                 bcnt = SZ_64K - 1;
332                         cidx = acnt;
333                 /*
334                  * If maxburst is greater than the fifo address_width,
335                  * use AB-synced transfers where A count is the fifo
336                  * address_width and B count is the maxburst. In this
337                  * case, we are limited to transfers of C count frames
338                  * of (address_width * maxburst) where C count is limited
339                  * to SZ_64K-1. This places an upper bound on the length
340                  * of an SG segment that can be handled.
341                  */
342                 } else {
343                         edesc->absync = true;
344                         bcnt = burst;
345                         ccnt = sg_dma_len(sg) / (acnt * bcnt);
346                         if (ccnt > (SZ_64K - 1)) {
347                                 dev_err(dev, "Exceeded max SG segment size\n");
348                                 return NULL;
349                         }
350                         cidx = acnt * bcnt;
351                 }
352
353                 if (direction == DMA_MEM_TO_DEV) {
354                         src = sg_dma_address(sg);
355                         dst = dev_addr;
356                         src_bidx = acnt;
357                         src_cidx = cidx;
358                         dst_bidx = 0;
359                         dst_cidx = 0;
360                 } else {
361                         src = dev_addr;
362                         dst = sg_dma_address(sg);
363                         src_bidx = 0;
364                         src_cidx = 0;
365                         dst_bidx = acnt;
366                         dst_cidx = cidx;
367                 }
368
369                 edesc->pset[i].opt = EDMA_TCC(EDMA_CHAN_SLOT(echan->ch_num));
370                 /* Configure A or AB synchronized transfers */
371                 if (edesc->absync)
372                         edesc->pset[i].opt |= SYNCDIM;
373
374                 /* If this is the last in a current SG set of transactions,
375                    enable interrupts so that next set is processed */
376                 if (!((i+1) % MAX_NR_SG))
377                         edesc->pset[i].opt |= TCINTEN;
378
379                 /* If this is the last set, enable completion interrupt flag */
380                 if (i == sg_len - 1)
381                         edesc->pset[i].opt |= TCINTEN;
382
383                 edesc->pset[i].src = src;
384                 edesc->pset[i].dst = dst;
385
386                 edesc->pset[i].src_dst_bidx = (dst_bidx << 16) | src_bidx;
387                 edesc->pset[i].src_dst_cidx = (dst_cidx << 16) | src_cidx;
388
389                 edesc->pset[i].a_b_cnt = bcnt << 16 | acnt;
390                 edesc->pset[i].ccnt = ccnt;
391                 edesc->pset[i].link_bcntrld = 0xffffffff;
392
393         }
394
395         return vchan_tx_prep(&echan->vchan, &edesc->vdesc, tx_flags);
396 }
397
398 static void edma_callback(unsigned ch_num, u16 ch_status, void *data)
399 {
400         struct edma_chan *echan = data;
401         struct device *dev = echan->vchan.chan.device->dev;
402         struct edma_desc *edesc;
403         unsigned long flags;
404         struct edmacc_param p;
405
406         /* Pause the channel */
407         edma_pause(echan->ch_num);
408
409         switch (ch_status) {
410         case DMA_COMPLETE:
411                 spin_lock_irqsave(&echan->vchan.lock, flags);
412
413                 edesc = echan->edesc;
414                 if (edesc) {
415                         if (edesc->processed == edesc->pset_nr) {
416                                 dev_dbg(dev, "Transfer complete, stopping channel %d\n", ch_num);
417                                 edma_stop(echan->ch_num);
418                                 vchan_cookie_complete(&edesc->vdesc);
419                         } else {
420                                 dev_dbg(dev, "Intermediate transfer complete on channel %d\n", ch_num);
421                         }
422
423                         edma_execute(echan);
424                 }
425
426                 spin_unlock_irqrestore(&echan->vchan.lock, flags);
427
428                 break;
429         case DMA_CC_ERROR:
430                 spin_lock_irqsave(&echan->vchan.lock, flags);
431
432                 edma_read_slot(EDMA_CHAN_SLOT(echan->slot[0]), &p);
433
434                 /*
435                  * Issue later based on missed flag which will be sure
436                  * to happen as:
437                  * (1) we finished transmitting an intermediate slot and
438                  *     edma_execute is coming up.
439                  * (2) or we finished current transfer and issue will
440                  *     call edma_execute.
441                  *
442                  * Important note: issuing can be dangerous here and
443                  * lead to some nasty recursion when we are in a NULL
444                  * slot. So we avoid doing so and set the missed flag.
445                  */
446                 if (p.a_b_cnt == 0 && p.ccnt == 0) {
447                         dev_dbg(dev, "Error occurred, looks like slot is null, just setting miss\n");
448                         echan->missed = 1;
449                 } else {
450                         /*
451                          * The slot is already programmed but the event got
452                          * missed, so its safe to issue it here.
453                          */
454                         dev_dbg(dev, "Error occurred but slot is non-null, TRIGGERING\n");
455                         edma_clean_channel(echan->ch_num);
456                         edma_stop(echan->ch_num);
457                         edma_start(echan->ch_num);
458                         edma_trigger_channel(echan->ch_num);
459                 }
460
461                 spin_unlock_irqrestore(&echan->vchan.lock, flags);
462
463                 break;
464         default:
465                 break;
466         }
467 }
468
469 /* Alloc channel resources */
470 static int edma_alloc_chan_resources(struct dma_chan *chan)
471 {
472         struct edma_chan *echan = to_edma_chan(chan);
473         struct device *dev = chan->device->dev;
474         int ret;
475         int a_ch_num;
476         LIST_HEAD(descs);
477
478         a_ch_num = edma_alloc_channel(echan->ch_num, edma_callback,
479                                         chan, EVENTQ_DEFAULT);
480
481         if (a_ch_num < 0) {
482                 ret = -ENODEV;
483                 goto err_no_chan;
484         }
485
486         if (a_ch_num != echan->ch_num) {
487                 dev_err(dev, "failed to allocate requested channel %u:%u\n",
488                         EDMA_CTLR(echan->ch_num),
489                         EDMA_CHAN_SLOT(echan->ch_num));
490                 ret = -ENODEV;
491                 goto err_wrong_chan;
492         }
493
494         echan->alloced = true;
495         echan->slot[0] = echan->ch_num;
496
497         dev_info(dev, "allocated channel for %u:%u\n",
498                  EDMA_CTLR(echan->ch_num), EDMA_CHAN_SLOT(echan->ch_num));
499
500         return 0;
501
502 err_wrong_chan:
503         edma_free_channel(a_ch_num);
504 err_no_chan:
505         return ret;
506 }
507
508 /* Free channel resources */
509 static void edma_free_chan_resources(struct dma_chan *chan)
510 {
511         struct edma_chan *echan = to_edma_chan(chan);
512         struct device *dev = chan->device->dev;
513         int i;
514
515         /* Terminate transfers */
516         edma_stop(echan->ch_num);
517
518         vchan_free_chan_resources(&echan->vchan);
519
520         /* Free EDMA PaRAM slots */
521         for (i = 1; i < EDMA_MAX_SLOTS; i++) {
522                 if (echan->slot[i] >= 0) {
523                         edma_free_slot(echan->slot[i]);
524                         echan->slot[i] = -1;
525                 }
526         }
527
528         /* Free EDMA channel */
529         if (echan->alloced) {
530                 edma_free_channel(echan->ch_num);
531                 echan->alloced = false;
532         }
533
534         dev_info(dev, "freeing channel for %u\n", echan->ch_num);
535 }
536
537 /* Send pending descriptor to hardware */
538 static void edma_issue_pending(struct dma_chan *chan)
539 {
540         struct edma_chan *echan = to_edma_chan(chan);
541         unsigned long flags;
542
543         spin_lock_irqsave(&echan->vchan.lock, flags);
544         if (vchan_issue_pending(&echan->vchan) && !echan->edesc)
545                 edma_execute(echan);
546         spin_unlock_irqrestore(&echan->vchan.lock, flags);
547 }
548
549 static size_t edma_desc_size(struct edma_desc *edesc)
550 {
551         int i;
552         size_t size;
553
554         if (edesc->absync)
555                 for (size = i = 0; i < edesc->pset_nr; i++)
556                         size += (edesc->pset[i].a_b_cnt & 0xffff) *
557                                 (edesc->pset[i].a_b_cnt >> 16) *
558                                  edesc->pset[i].ccnt;
559         else
560                 size = (edesc->pset[0].a_b_cnt & 0xffff) *
561                         (edesc->pset[0].a_b_cnt >> 16) +
562                         (edesc->pset[0].a_b_cnt & 0xffff) *
563                         (SZ_64K - 1) * edesc->pset[0].ccnt;
564
565         return size;
566 }
567
568 /* Check request completion status */
569 static enum dma_status edma_tx_status(struct dma_chan *chan,
570                                       dma_cookie_t cookie,
571                                       struct dma_tx_state *txstate)
572 {
573         struct edma_chan *echan = to_edma_chan(chan);
574         struct virt_dma_desc *vdesc;
575         enum dma_status ret;
576         unsigned long flags;
577
578         ret = dma_cookie_status(chan, cookie, txstate);
579         if (ret == DMA_SUCCESS || !txstate)
580                 return ret;
581
582         spin_lock_irqsave(&echan->vchan.lock, flags);
583         vdesc = vchan_find_desc(&echan->vchan, cookie);
584         if (vdesc) {
585                 txstate->residue = edma_desc_size(to_edma_desc(&vdesc->tx));
586         } else if (echan->edesc && echan->edesc->vdesc.tx.cookie == cookie) {
587                 struct edma_desc *edesc = echan->edesc;
588                 txstate->residue = edma_desc_size(edesc);
589         }
590         spin_unlock_irqrestore(&echan->vchan.lock, flags);
591
592         return ret;
593 }
594
595 static void __init edma_chan_init(struct edma_cc *ecc,
596                                   struct dma_device *dma,
597                                   struct edma_chan *echans)
598 {
599         int i, j;
600
601         for (i = 0; i < EDMA_CHANS; i++) {
602                 struct edma_chan *echan = &echans[i];
603                 echan->ch_num = EDMA_CTLR_CHAN(ecc->ctlr, i);
604                 echan->ecc = ecc;
605                 echan->vchan.desc_free = edma_desc_free;
606
607                 vchan_init(&echan->vchan, dma);
608
609                 INIT_LIST_HEAD(&echan->node);
610                 for (j = 0; j < EDMA_MAX_SLOTS; j++)
611                         echan->slot[j] = -1;
612         }
613 }
614
615 static void edma_dma_init(struct edma_cc *ecc, struct dma_device *dma,
616                           struct device *dev)
617 {
618         dma->device_prep_slave_sg = edma_prep_slave_sg;
619         dma->device_alloc_chan_resources = edma_alloc_chan_resources;
620         dma->device_free_chan_resources = edma_free_chan_resources;
621         dma->device_issue_pending = edma_issue_pending;
622         dma->device_tx_status = edma_tx_status;
623         dma->device_control = edma_control;
624         dma->dev = dev;
625
626         INIT_LIST_HEAD(&dma->channels);
627 }
628
629 static int edma_probe(struct platform_device *pdev)
630 {
631         struct edma_cc *ecc;
632         int ret;
633
634         ecc = devm_kzalloc(&pdev->dev, sizeof(*ecc), GFP_KERNEL);
635         if (!ecc) {
636                 dev_err(&pdev->dev, "Can't allocate controller\n");
637                 return -ENOMEM;
638         }
639
640         ecc->ctlr = pdev->id;
641         ecc->dummy_slot = edma_alloc_slot(ecc->ctlr, EDMA_SLOT_ANY);
642         if (ecc->dummy_slot < 0) {
643                 dev_err(&pdev->dev, "Can't allocate PaRAM dummy slot\n");
644                 return -EIO;
645         }
646
647         dma_cap_zero(ecc->dma_slave.cap_mask);
648         dma_cap_set(DMA_SLAVE, ecc->dma_slave.cap_mask);
649
650         edma_dma_init(ecc, &ecc->dma_slave, &pdev->dev);
651
652         edma_chan_init(ecc, &ecc->dma_slave, ecc->slave_chans);
653
654         ret = dma_async_device_register(&ecc->dma_slave);
655         if (ret)
656                 goto err_reg1;
657
658         platform_set_drvdata(pdev, ecc);
659
660         dev_info(&pdev->dev, "TI EDMA DMA engine driver\n");
661
662         return 0;
663
664 err_reg1:
665         edma_free_slot(ecc->dummy_slot);
666         return ret;
667 }
668
669 static int edma_remove(struct platform_device *pdev)
670 {
671         struct device *dev = &pdev->dev;
672         struct edma_cc *ecc = dev_get_drvdata(dev);
673
674         dma_async_device_unregister(&ecc->dma_slave);
675         edma_free_slot(ecc->dummy_slot);
676
677         return 0;
678 }
679
680 static struct platform_driver edma_driver = {
681         .probe          = edma_probe,
682         .remove         = edma_remove,
683         .driver = {
684                 .name = "edma-dma-engine",
685                 .owner = THIS_MODULE,
686         },
687 };
688
689 bool edma_filter_fn(struct dma_chan *chan, void *param)
690 {
691         if (chan->device->dev->driver == &edma_driver.driver) {
692                 struct edma_chan *echan = to_edma_chan(chan);
693                 unsigned ch_req = *(unsigned *)param;
694                 return ch_req == echan->ch_num;
695         }
696         return false;
697 }
698 EXPORT_SYMBOL(edma_filter_fn);
699
700 static struct platform_device *pdev0, *pdev1;
701
702 static const struct platform_device_info edma_dev_info0 = {
703         .name = "edma-dma-engine",
704         .id = 0,
705 };
706
707 static const struct platform_device_info edma_dev_info1 = {
708         .name = "edma-dma-engine",
709         .id = 1,
710 };
711
712 static int edma_init(void)
713 {
714         int ret = platform_driver_register(&edma_driver);
715
716         if (ret == 0) {
717                 pdev0 = platform_device_register_full(&edma_dev_info0);
718                 if (IS_ERR(pdev0)) {
719                         platform_driver_unregister(&edma_driver);
720                         ret = PTR_ERR(pdev0);
721                         goto out;
722                 }
723                 pdev0->dev.dma_mask = &pdev0->dev.coherent_dma_mask;
724                 pdev0->dev.coherent_dma_mask = DMA_BIT_MASK(32);
725         }
726
727         if (EDMA_CTLRS == 2) {
728                 pdev1 = platform_device_register_full(&edma_dev_info1);
729                 if (IS_ERR(pdev1)) {
730                         platform_driver_unregister(&edma_driver);
731                         platform_device_unregister(pdev0);
732                         ret = PTR_ERR(pdev1);
733                 }
734                 pdev1->dev.dma_mask = &pdev1->dev.coherent_dma_mask;
735                 pdev1->dev.coherent_dma_mask = DMA_BIT_MASK(32);
736         }
737
738 out:
739         return ret;
740 }
741 subsys_initcall(edma_init);
742
743 static void __exit edma_exit(void)
744 {
745         platform_device_unregister(pdev0);
746         if (pdev1)
747                 platform_device_unregister(pdev1);
748         platform_driver_unregister(&edma_driver);
749 }
750 module_exit(edma_exit);
751
752 MODULE_AUTHOR("Matt Porter <mporter@ti.com>");
753 MODULE_DESCRIPTION("TI EDMA DMA engine driver");
754 MODULE_LICENSE("GPL v2");