xref: /openbmc/linux/drivers/dma/txx9dmac.c (revision d4295e12)
1 /*
2  * Driver for the TXx9 SoC DMA Controller
3  *
4  * Copyright (C) 2009 Atsushi Nemoto
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 #include <linux/dma-mapping.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/io.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/slab.h>
17 #include <linux/scatterlist.h>
18 
19 #include "dmaengine.h"
20 #include "txx9dmac.h"
21 
22 static struct txx9dmac_chan *to_txx9dmac_chan(struct dma_chan *chan)
23 {
24 	return container_of(chan, struct txx9dmac_chan, chan);
25 }
26 
27 static struct txx9dmac_cregs __iomem *__dma_regs(const struct txx9dmac_chan *dc)
28 {
29 	return dc->ch_regs;
30 }
31 
32 static struct txx9dmac_cregs32 __iomem *__dma_regs32(
33 	const struct txx9dmac_chan *dc)
34 {
35 	return dc->ch_regs;
36 }
37 
38 #define channel64_readq(dc, name) \
39 	__raw_readq(&(__dma_regs(dc)->name))
40 #define channel64_writeq(dc, name, val) \
41 	__raw_writeq((val), &(__dma_regs(dc)->name))
42 #define channel64_readl(dc, name) \
43 	__raw_readl(&(__dma_regs(dc)->name))
44 #define channel64_writel(dc, name, val) \
45 	__raw_writel((val), &(__dma_regs(dc)->name))
46 
47 #define channel32_readl(dc, name) \
48 	__raw_readl(&(__dma_regs32(dc)->name))
49 #define channel32_writel(dc, name, val) \
50 	__raw_writel((val), &(__dma_regs32(dc)->name))
51 
52 #define channel_readq(dc, name) channel64_readq(dc, name)
53 #define channel_writeq(dc, name, val) channel64_writeq(dc, name, val)
54 #define channel_readl(dc, name) \
55 	(is_dmac64(dc) ? \
56 	 channel64_readl(dc, name) : channel32_readl(dc, name))
57 #define channel_writel(dc, name, val) \
58 	(is_dmac64(dc) ? \
59 	 channel64_writel(dc, name, val) : channel32_writel(dc, name, val))
60 
61 static dma_addr_t channel64_read_CHAR(const struct txx9dmac_chan *dc)
62 {
63 	if (sizeof(__dma_regs(dc)->CHAR) == sizeof(u64))
64 		return channel64_readq(dc, CHAR);
65 	else
66 		return channel64_readl(dc, CHAR);
67 }
68 
69 static void channel64_write_CHAR(const struct txx9dmac_chan *dc, dma_addr_t val)
70 {
71 	if (sizeof(__dma_regs(dc)->CHAR) == sizeof(u64))
72 		channel64_writeq(dc, CHAR, val);
73 	else
74 		channel64_writel(dc, CHAR, val);
75 }
76 
77 static void channel64_clear_CHAR(const struct txx9dmac_chan *dc)
78 {
79 #if defined(CONFIG_32BIT) && !defined(CONFIG_PHYS_ADDR_T_64BIT)
80 	channel64_writel(dc, CHAR, 0);
81 	channel64_writel(dc, __pad_CHAR, 0);
82 #else
83 	channel64_writeq(dc, CHAR, 0);
84 #endif
85 }
86 
87 static dma_addr_t channel_read_CHAR(const struct txx9dmac_chan *dc)
88 {
89 	if (is_dmac64(dc))
90 		return channel64_read_CHAR(dc);
91 	else
92 		return channel32_readl(dc, CHAR);
93 }
94 
95 static void channel_write_CHAR(const struct txx9dmac_chan *dc, dma_addr_t val)
96 {
97 	if (is_dmac64(dc))
98 		channel64_write_CHAR(dc, val);
99 	else
100 		channel32_writel(dc, CHAR, val);
101 }
102 
103 static struct txx9dmac_regs __iomem *__txx9dmac_regs(
104 	const struct txx9dmac_dev *ddev)
105 {
106 	return ddev->regs;
107 }
108 
109 static struct txx9dmac_regs32 __iomem *__txx9dmac_regs32(
110 	const struct txx9dmac_dev *ddev)
111 {
112 	return ddev->regs;
113 }
114 
115 #define dma64_readl(ddev, name) \
116 	__raw_readl(&(__txx9dmac_regs(ddev)->name))
117 #define dma64_writel(ddev, name, val) \
118 	__raw_writel((val), &(__txx9dmac_regs(ddev)->name))
119 
120 #define dma32_readl(ddev, name) \
121 	__raw_readl(&(__txx9dmac_regs32(ddev)->name))
122 #define dma32_writel(ddev, name, val) \
123 	__raw_writel((val), &(__txx9dmac_regs32(ddev)->name))
124 
125 #define dma_readl(ddev, name) \
126 	(__is_dmac64(ddev) ? \
127 	dma64_readl(ddev, name) : dma32_readl(ddev, name))
128 #define dma_writel(ddev, name, val) \
129 	(__is_dmac64(ddev) ? \
130 	dma64_writel(ddev, name, val) : dma32_writel(ddev, name, val))
131 
132 static struct device *chan2dev(struct dma_chan *chan)
133 {
134 	return &chan->dev->device;
135 }
136 static struct device *chan2parent(struct dma_chan *chan)
137 {
138 	return chan->dev->device.parent;
139 }
140 
141 static struct txx9dmac_desc *
142 txd_to_txx9dmac_desc(struct dma_async_tx_descriptor *txd)
143 {
144 	return container_of(txd, struct txx9dmac_desc, txd);
145 }
146 
147 static dma_addr_t desc_read_CHAR(const struct txx9dmac_chan *dc,
148 				 const struct txx9dmac_desc *desc)
149 {
150 	return is_dmac64(dc) ? desc->hwdesc.CHAR : desc->hwdesc32.CHAR;
151 }
152 
153 static void desc_write_CHAR(const struct txx9dmac_chan *dc,
154 			    struct txx9dmac_desc *desc, dma_addr_t val)
155 {
156 	if (is_dmac64(dc))
157 		desc->hwdesc.CHAR = val;
158 	else
159 		desc->hwdesc32.CHAR = val;
160 }
161 
162 #define TXX9_DMA_MAX_COUNT	0x04000000
163 
164 #define TXX9_DMA_INITIAL_DESC_COUNT	64
165 
166 static struct txx9dmac_desc *txx9dmac_first_active(struct txx9dmac_chan *dc)
167 {
168 	return list_entry(dc->active_list.next,
169 			  struct txx9dmac_desc, desc_node);
170 }
171 
172 static struct txx9dmac_desc *txx9dmac_last_active(struct txx9dmac_chan *dc)
173 {
174 	return list_entry(dc->active_list.prev,
175 			  struct txx9dmac_desc, desc_node);
176 }
177 
178 static struct txx9dmac_desc *txx9dmac_first_queued(struct txx9dmac_chan *dc)
179 {
180 	return list_entry(dc->queue.next, struct txx9dmac_desc, desc_node);
181 }
182 
183 static struct txx9dmac_desc *txx9dmac_last_child(struct txx9dmac_desc *desc)
184 {
185 	if (!list_empty(&desc->tx_list))
186 		desc = list_entry(desc->tx_list.prev, typeof(*desc), desc_node);
187 	return desc;
188 }
189 
190 static dma_cookie_t txx9dmac_tx_submit(struct dma_async_tx_descriptor *tx);
191 
192 static struct txx9dmac_desc *txx9dmac_desc_alloc(struct txx9dmac_chan *dc,
193 						 gfp_t flags)
194 {
195 	struct txx9dmac_dev *ddev = dc->ddev;
196 	struct txx9dmac_desc *desc;
197 
198 	desc = kzalloc(sizeof(*desc), flags);
199 	if (!desc)
200 		return NULL;
201 	INIT_LIST_HEAD(&desc->tx_list);
202 	dma_async_tx_descriptor_init(&desc->txd, &dc->chan);
203 	desc->txd.tx_submit = txx9dmac_tx_submit;
204 	/* txd.flags will be overwritten in prep funcs */
205 	desc->txd.flags = DMA_CTRL_ACK;
206 	desc->txd.phys = dma_map_single(chan2parent(&dc->chan), &desc->hwdesc,
207 					ddev->descsize, DMA_TO_DEVICE);
208 	return desc;
209 }
210 
211 static struct txx9dmac_desc *txx9dmac_desc_get(struct txx9dmac_chan *dc)
212 {
213 	struct txx9dmac_desc *desc, *_desc;
214 	struct txx9dmac_desc *ret = NULL;
215 	unsigned int i = 0;
216 
217 	spin_lock_bh(&dc->lock);
218 	list_for_each_entry_safe(desc, _desc, &dc->free_list, desc_node) {
219 		if (async_tx_test_ack(&desc->txd)) {
220 			list_del(&desc->desc_node);
221 			ret = desc;
222 			break;
223 		}
224 		dev_dbg(chan2dev(&dc->chan), "desc %p not ACKed\n", desc);
225 		i++;
226 	}
227 	spin_unlock_bh(&dc->lock);
228 
229 	dev_vdbg(chan2dev(&dc->chan), "scanned %u descriptors on freelist\n",
230 		 i);
231 	if (!ret) {
232 		ret = txx9dmac_desc_alloc(dc, GFP_ATOMIC);
233 		if (ret) {
234 			spin_lock_bh(&dc->lock);
235 			dc->descs_allocated++;
236 			spin_unlock_bh(&dc->lock);
237 		} else
238 			dev_err(chan2dev(&dc->chan),
239 				"not enough descriptors available\n");
240 	}
241 	return ret;
242 }
243 
244 static void txx9dmac_sync_desc_for_cpu(struct txx9dmac_chan *dc,
245 				       struct txx9dmac_desc *desc)
246 {
247 	struct txx9dmac_dev *ddev = dc->ddev;
248 	struct txx9dmac_desc *child;
249 
250 	list_for_each_entry(child, &desc->tx_list, desc_node)
251 		dma_sync_single_for_cpu(chan2parent(&dc->chan),
252 				child->txd.phys, ddev->descsize,
253 				DMA_TO_DEVICE);
254 	dma_sync_single_for_cpu(chan2parent(&dc->chan),
255 			desc->txd.phys, ddev->descsize,
256 			DMA_TO_DEVICE);
257 }
258 
259 /*
260  * Move a descriptor, including any children, to the free list.
261  * `desc' must not be on any lists.
262  */
263 static void txx9dmac_desc_put(struct txx9dmac_chan *dc,
264 			      struct txx9dmac_desc *desc)
265 {
266 	if (desc) {
267 		struct txx9dmac_desc *child;
268 
269 		txx9dmac_sync_desc_for_cpu(dc, desc);
270 
271 		spin_lock_bh(&dc->lock);
272 		list_for_each_entry(child, &desc->tx_list, desc_node)
273 			dev_vdbg(chan2dev(&dc->chan),
274 				 "moving child desc %p to freelist\n",
275 				 child);
276 		list_splice_init(&desc->tx_list, &dc->free_list);
277 		dev_vdbg(chan2dev(&dc->chan), "moving desc %p to freelist\n",
278 			 desc);
279 		list_add(&desc->desc_node, &dc->free_list);
280 		spin_unlock_bh(&dc->lock);
281 	}
282 }
283 
284 /*----------------------------------------------------------------------*/
285 
286 static void txx9dmac_dump_regs(struct txx9dmac_chan *dc)
287 {
288 	if (is_dmac64(dc))
289 		dev_err(chan2dev(&dc->chan),
290 			"  CHAR: %#llx SAR: %#llx DAR: %#llx CNTR: %#x"
291 			" SAIR: %#x DAIR: %#x CCR: %#x CSR: %#x\n",
292 			(u64)channel64_read_CHAR(dc),
293 			channel64_readq(dc, SAR),
294 			channel64_readq(dc, DAR),
295 			channel64_readl(dc, CNTR),
296 			channel64_readl(dc, SAIR),
297 			channel64_readl(dc, DAIR),
298 			channel64_readl(dc, CCR),
299 			channel64_readl(dc, CSR));
300 	else
301 		dev_err(chan2dev(&dc->chan),
302 			"  CHAR: %#x SAR: %#x DAR: %#x CNTR: %#x"
303 			" SAIR: %#x DAIR: %#x CCR: %#x CSR: %#x\n",
304 			channel32_readl(dc, CHAR),
305 			channel32_readl(dc, SAR),
306 			channel32_readl(dc, DAR),
307 			channel32_readl(dc, CNTR),
308 			channel32_readl(dc, SAIR),
309 			channel32_readl(dc, DAIR),
310 			channel32_readl(dc, CCR),
311 			channel32_readl(dc, CSR));
312 }
313 
314 static void txx9dmac_reset_chan(struct txx9dmac_chan *dc)
315 {
316 	channel_writel(dc, CCR, TXX9_DMA_CCR_CHRST);
317 	if (is_dmac64(dc)) {
318 		channel64_clear_CHAR(dc);
319 		channel_writeq(dc, SAR, 0);
320 		channel_writeq(dc, DAR, 0);
321 	} else {
322 		channel_writel(dc, CHAR, 0);
323 		channel_writel(dc, SAR, 0);
324 		channel_writel(dc, DAR, 0);
325 	}
326 	channel_writel(dc, CNTR, 0);
327 	channel_writel(dc, SAIR, 0);
328 	channel_writel(dc, DAIR, 0);
329 	channel_writel(dc, CCR, 0);
330 	mmiowb();
331 }
332 
333 /* Called with dc->lock held and bh disabled */
334 static void txx9dmac_dostart(struct txx9dmac_chan *dc,
335 			     struct txx9dmac_desc *first)
336 {
337 	struct txx9dmac_slave *ds = dc->chan.private;
338 	u32 sai, dai;
339 
340 	dev_vdbg(chan2dev(&dc->chan), "dostart %u %p\n",
341 		 first->txd.cookie, first);
342 	/* ASSERT:  channel is idle */
343 	if (channel_readl(dc, CSR) & TXX9_DMA_CSR_XFACT) {
344 		dev_err(chan2dev(&dc->chan),
345 			"BUG: Attempted to start non-idle channel\n");
346 		txx9dmac_dump_regs(dc);
347 		/* The tasklet will hopefully advance the queue... */
348 		return;
349 	}
350 
351 	if (is_dmac64(dc)) {
352 		channel64_writel(dc, CNTR, 0);
353 		channel64_writel(dc, CSR, 0xffffffff);
354 		if (ds) {
355 			if (ds->tx_reg) {
356 				sai = ds->reg_width;
357 				dai = 0;
358 			} else {
359 				sai = 0;
360 				dai = ds->reg_width;
361 			}
362 		} else {
363 			sai = 8;
364 			dai = 8;
365 		}
366 		channel64_writel(dc, SAIR, sai);
367 		channel64_writel(dc, DAIR, dai);
368 		/* All 64-bit DMAC supports SMPCHN */
369 		channel64_writel(dc, CCR, dc->ccr);
370 		/* Writing a non zero value to CHAR will assert XFACT */
371 		channel64_write_CHAR(dc, first->txd.phys);
372 	} else {
373 		channel32_writel(dc, CNTR, 0);
374 		channel32_writel(dc, CSR, 0xffffffff);
375 		if (ds) {
376 			if (ds->tx_reg) {
377 				sai = ds->reg_width;
378 				dai = 0;
379 			} else {
380 				sai = 0;
381 				dai = ds->reg_width;
382 			}
383 		} else {
384 			sai = 4;
385 			dai = 4;
386 		}
387 		channel32_writel(dc, SAIR, sai);
388 		channel32_writel(dc, DAIR, dai);
389 		if (txx9_dma_have_SMPCHN()) {
390 			channel32_writel(dc, CCR, dc->ccr);
391 			/* Writing a non zero value to CHAR will assert XFACT */
392 			channel32_writel(dc, CHAR, first->txd.phys);
393 		} else {
394 			channel32_writel(dc, CHAR, first->txd.phys);
395 			channel32_writel(dc, CCR, dc->ccr);
396 		}
397 	}
398 }
399 
400 /*----------------------------------------------------------------------*/
401 
402 static void
403 txx9dmac_descriptor_complete(struct txx9dmac_chan *dc,
404 			     struct txx9dmac_desc *desc)
405 {
406 	struct dmaengine_desc_callback cb;
407 	struct dma_async_tx_descriptor *txd = &desc->txd;
408 
409 	dev_vdbg(chan2dev(&dc->chan), "descriptor %u %p complete\n",
410 		 txd->cookie, desc);
411 
412 	dma_cookie_complete(txd);
413 	dmaengine_desc_get_callback(txd, &cb);
414 
415 	txx9dmac_sync_desc_for_cpu(dc, desc);
416 	list_splice_init(&desc->tx_list, &dc->free_list);
417 	list_move(&desc->desc_node, &dc->free_list);
418 
419 	dma_descriptor_unmap(txd);
420 	/*
421 	 * The API requires that no submissions are done from a
422 	 * callback, so we don't need to drop the lock here
423 	 */
424 	dmaengine_desc_callback_invoke(&cb, NULL);
425 	dma_run_dependencies(txd);
426 }
427 
428 static void txx9dmac_dequeue(struct txx9dmac_chan *dc, struct list_head *list)
429 {
430 	struct txx9dmac_dev *ddev = dc->ddev;
431 	struct txx9dmac_desc *desc;
432 	struct txx9dmac_desc *prev = NULL;
433 
434 	BUG_ON(!list_empty(list));
435 	do {
436 		desc = txx9dmac_first_queued(dc);
437 		if (prev) {
438 			desc_write_CHAR(dc, prev, desc->txd.phys);
439 			dma_sync_single_for_device(chan2parent(&dc->chan),
440 				prev->txd.phys, ddev->descsize,
441 				DMA_TO_DEVICE);
442 		}
443 		prev = txx9dmac_last_child(desc);
444 		list_move_tail(&desc->desc_node, list);
445 		/* Make chain-completion interrupt happen */
446 		if ((desc->txd.flags & DMA_PREP_INTERRUPT) &&
447 		    !txx9dmac_chan_INTENT(dc))
448 			break;
449 	} while (!list_empty(&dc->queue));
450 }
451 
452 static void txx9dmac_complete_all(struct txx9dmac_chan *dc)
453 {
454 	struct txx9dmac_desc *desc, *_desc;
455 	LIST_HEAD(list);
456 
457 	/*
458 	 * Submit queued descriptors ASAP, i.e. before we go through
459 	 * the completed ones.
460 	 */
461 	list_splice_init(&dc->active_list, &list);
462 	if (!list_empty(&dc->queue)) {
463 		txx9dmac_dequeue(dc, &dc->active_list);
464 		txx9dmac_dostart(dc, txx9dmac_first_active(dc));
465 	}
466 
467 	list_for_each_entry_safe(desc, _desc, &list, desc_node)
468 		txx9dmac_descriptor_complete(dc, desc);
469 }
470 
471 static void txx9dmac_dump_desc(struct txx9dmac_chan *dc,
472 			       struct txx9dmac_hwdesc *desc)
473 {
474 	if (is_dmac64(dc)) {
475 #ifdef TXX9_DMA_USE_SIMPLE_CHAIN
476 		dev_crit(chan2dev(&dc->chan),
477 			 "  desc: ch%#llx s%#llx d%#llx c%#x\n",
478 			 (u64)desc->CHAR, desc->SAR, desc->DAR, desc->CNTR);
479 #else
480 		dev_crit(chan2dev(&dc->chan),
481 			 "  desc: ch%#llx s%#llx d%#llx c%#x"
482 			 " si%#x di%#x cc%#x cs%#x\n",
483 			 (u64)desc->CHAR, desc->SAR, desc->DAR, desc->CNTR,
484 			 desc->SAIR, desc->DAIR, desc->CCR, desc->CSR);
485 #endif
486 	} else {
487 		struct txx9dmac_hwdesc32 *d = (struct txx9dmac_hwdesc32 *)desc;
488 #ifdef TXX9_DMA_USE_SIMPLE_CHAIN
489 		dev_crit(chan2dev(&dc->chan),
490 			 "  desc: ch%#x s%#x d%#x c%#x\n",
491 			 d->CHAR, d->SAR, d->DAR, d->CNTR);
492 #else
493 		dev_crit(chan2dev(&dc->chan),
494 			 "  desc: ch%#x s%#x d%#x c%#x"
495 			 " si%#x di%#x cc%#x cs%#x\n",
496 			 d->CHAR, d->SAR, d->DAR, d->CNTR,
497 			 d->SAIR, d->DAIR, d->CCR, d->CSR);
498 #endif
499 	}
500 }
501 
502 static void txx9dmac_handle_error(struct txx9dmac_chan *dc, u32 csr)
503 {
504 	struct txx9dmac_desc *bad_desc;
505 	struct txx9dmac_desc *child;
506 	u32 errors;
507 
508 	/*
509 	 * The descriptor currently at the head of the active list is
510 	 * borked. Since we don't have any way to report errors, we'll
511 	 * just have to scream loudly and try to carry on.
512 	 */
513 	dev_crit(chan2dev(&dc->chan), "Abnormal Chain Completion\n");
514 	txx9dmac_dump_regs(dc);
515 
516 	bad_desc = txx9dmac_first_active(dc);
517 	list_del_init(&bad_desc->desc_node);
518 
519 	/* Clear all error flags and try to restart the controller */
520 	errors = csr & (TXX9_DMA_CSR_ABCHC |
521 			TXX9_DMA_CSR_CFERR | TXX9_DMA_CSR_CHERR |
522 			TXX9_DMA_CSR_DESERR | TXX9_DMA_CSR_SORERR);
523 	channel_writel(dc, CSR, errors);
524 
525 	if (list_empty(&dc->active_list) && !list_empty(&dc->queue))
526 		txx9dmac_dequeue(dc, &dc->active_list);
527 	if (!list_empty(&dc->active_list))
528 		txx9dmac_dostart(dc, txx9dmac_first_active(dc));
529 
530 	dev_crit(chan2dev(&dc->chan),
531 		 "Bad descriptor submitted for DMA! (cookie: %d)\n",
532 		 bad_desc->txd.cookie);
533 	txx9dmac_dump_desc(dc, &bad_desc->hwdesc);
534 	list_for_each_entry(child, &bad_desc->tx_list, desc_node)
535 		txx9dmac_dump_desc(dc, &child->hwdesc);
536 	/* Pretend the descriptor completed successfully */
537 	txx9dmac_descriptor_complete(dc, bad_desc);
538 }
539 
540 static void txx9dmac_scan_descriptors(struct txx9dmac_chan *dc)
541 {
542 	dma_addr_t chain;
543 	struct txx9dmac_desc *desc, *_desc;
544 	struct txx9dmac_desc *child;
545 	u32 csr;
546 
547 	if (is_dmac64(dc)) {
548 		chain = channel64_read_CHAR(dc);
549 		csr = channel64_readl(dc, CSR);
550 		channel64_writel(dc, CSR, csr);
551 	} else {
552 		chain = channel32_readl(dc, CHAR);
553 		csr = channel32_readl(dc, CSR);
554 		channel32_writel(dc, CSR, csr);
555 	}
556 	/* For dynamic chain, we should look at XFACT instead of NCHNC */
557 	if (!(csr & (TXX9_DMA_CSR_XFACT | TXX9_DMA_CSR_ABCHC))) {
558 		/* Everything we've submitted is done */
559 		txx9dmac_complete_all(dc);
560 		return;
561 	}
562 	if (!(csr & TXX9_DMA_CSR_CHNEN))
563 		chain = 0;	/* last descriptor of this chain */
564 
565 	dev_vdbg(chan2dev(&dc->chan), "scan_descriptors: char=%#llx\n",
566 		 (u64)chain);
567 
568 	list_for_each_entry_safe(desc, _desc, &dc->active_list, desc_node) {
569 		if (desc_read_CHAR(dc, desc) == chain) {
570 			/* This one is currently in progress */
571 			if (csr & TXX9_DMA_CSR_ABCHC)
572 				goto scan_done;
573 			return;
574 		}
575 
576 		list_for_each_entry(child, &desc->tx_list, desc_node)
577 			if (desc_read_CHAR(dc, child) == chain) {
578 				/* Currently in progress */
579 				if (csr & TXX9_DMA_CSR_ABCHC)
580 					goto scan_done;
581 				return;
582 			}
583 
584 		/*
585 		 * No descriptors so far seem to be in progress, i.e.
586 		 * this one must be done.
587 		 */
588 		txx9dmac_descriptor_complete(dc, desc);
589 	}
590 scan_done:
591 	if (csr & TXX9_DMA_CSR_ABCHC) {
592 		txx9dmac_handle_error(dc, csr);
593 		return;
594 	}
595 
596 	dev_err(chan2dev(&dc->chan),
597 		"BUG: All descriptors done, but channel not idle!\n");
598 
599 	/* Try to continue after resetting the channel... */
600 	txx9dmac_reset_chan(dc);
601 
602 	if (!list_empty(&dc->queue)) {
603 		txx9dmac_dequeue(dc, &dc->active_list);
604 		txx9dmac_dostart(dc, txx9dmac_first_active(dc));
605 	}
606 }
607 
608 static void txx9dmac_chan_tasklet(unsigned long data)
609 {
610 	int irq;
611 	u32 csr;
612 	struct txx9dmac_chan *dc;
613 
614 	dc = (struct txx9dmac_chan *)data;
615 	csr = channel_readl(dc, CSR);
616 	dev_vdbg(chan2dev(&dc->chan), "tasklet: status=%x\n", csr);
617 
618 	spin_lock(&dc->lock);
619 	if (csr & (TXX9_DMA_CSR_ABCHC | TXX9_DMA_CSR_NCHNC |
620 		   TXX9_DMA_CSR_NTRNFC))
621 		txx9dmac_scan_descriptors(dc);
622 	spin_unlock(&dc->lock);
623 	irq = dc->irq;
624 
625 	enable_irq(irq);
626 }
627 
628 static irqreturn_t txx9dmac_chan_interrupt(int irq, void *dev_id)
629 {
630 	struct txx9dmac_chan *dc = dev_id;
631 
632 	dev_vdbg(chan2dev(&dc->chan), "interrupt: status=%#x\n",
633 			channel_readl(dc, CSR));
634 
635 	tasklet_schedule(&dc->tasklet);
636 	/*
637 	 * Just disable the interrupts. We'll turn them back on in the
638 	 * softirq handler.
639 	 */
640 	disable_irq_nosync(irq);
641 
642 	return IRQ_HANDLED;
643 }
644 
645 static void txx9dmac_tasklet(unsigned long data)
646 {
647 	int irq;
648 	u32 csr;
649 	struct txx9dmac_chan *dc;
650 
651 	struct txx9dmac_dev *ddev = (struct txx9dmac_dev *)data;
652 	u32 mcr;
653 	int i;
654 
655 	mcr = dma_readl(ddev, MCR);
656 	dev_vdbg(ddev->chan[0]->dma.dev, "tasklet: mcr=%x\n", mcr);
657 	for (i = 0; i < TXX9_DMA_MAX_NR_CHANNELS; i++) {
658 		if ((mcr >> (24 + i)) & 0x11) {
659 			dc = ddev->chan[i];
660 			csr = channel_readl(dc, CSR);
661 			dev_vdbg(chan2dev(&dc->chan), "tasklet: status=%x\n",
662 				 csr);
663 			spin_lock(&dc->lock);
664 			if (csr & (TXX9_DMA_CSR_ABCHC | TXX9_DMA_CSR_NCHNC |
665 				   TXX9_DMA_CSR_NTRNFC))
666 				txx9dmac_scan_descriptors(dc);
667 			spin_unlock(&dc->lock);
668 		}
669 	}
670 	irq = ddev->irq;
671 
672 	enable_irq(irq);
673 }
674 
675 static irqreturn_t txx9dmac_interrupt(int irq, void *dev_id)
676 {
677 	struct txx9dmac_dev *ddev = dev_id;
678 
679 	dev_vdbg(ddev->chan[0]->dma.dev, "interrupt: status=%#x\n",
680 			dma_readl(ddev, MCR));
681 
682 	tasklet_schedule(&ddev->tasklet);
683 	/*
684 	 * Just disable the interrupts. We'll turn them back on in the
685 	 * softirq handler.
686 	 */
687 	disable_irq_nosync(irq);
688 
689 	return IRQ_HANDLED;
690 }
691 
692 /*----------------------------------------------------------------------*/
693 
694 static dma_cookie_t txx9dmac_tx_submit(struct dma_async_tx_descriptor *tx)
695 {
696 	struct txx9dmac_desc *desc = txd_to_txx9dmac_desc(tx);
697 	struct txx9dmac_chan *dc = to_txx9dmac_chan(tx->chan);
698 	dma_cookie_t cookie;
699 
700 	spin_lock_bh(&dc->lock);
701 	cookie = dma_cookie_assign(tx);
702 
703 	dev_vdbg(chan2dev(tx->chan), "tx_submit: queued %u %p\n",
704 		 desc->txd.cookie, desc);
705 
706 	list_add_tail(&desc->desc_node, &dc->queue);
707 	spin_unlock_bh(&dc->lock);
708 
709 	return cookie;
710 }
711 
712 static struct dma_async_tx_descriptor *
713 txx9dmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
714 		size_t len, unsigned long flags)
715 {
716 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
717 	struct txx9dmac_dev *ddev = dc->ddev;
718 	struct txx9dmac_desc *desc;
719 	struct txx9dmac_desc *first;
720 	struct txx9dmac_desc *prev;
721 	size_t xfer_count;
722 	size_t offset;
723 
724 	dev_vdbg(chan2dev(chan), "prep_dma_memcpy d%#llx s%#llx l%#zx f%#lx\n",
725 		 (u64)dest, (u64)src, len, flags);
726 
727 	if (unlikely(!len)) {
728 		dev_dbg(chan2dev(chan), "prep_dma_memcpy: length is zero!\n");
729 		return NULL;
730 	}
731 
732 	prev = first = NULL;
733 
734 	for (offset = 0; offset < len; offset += xfer_count) {
735 		xfer_count = min_t(size_t, len - offset, TXX9_DMA_MAX_COUNT);
736 		/*
737 		 * Workaround for ERT-TX49H2-033, ERT-TX49H3-020,
738 		 * ERT-TX49H4-016 (slightly conservative)
739 		 */
740 		if (__is_dmac64(ddev)) {
741 			if (xfer_count > 0x100 &&
742 			    (xfer_count & 0xff) >= 0xfa &&
743 			    (xfer_count & 0xff) <= 0xff)
744 				xfer_count -= 0x20;
745 		} else {
746 			if (xfer_count > 0x80 &&
747 			    (xfer_count & 0x7f) >= 0x7e &&
748 			    (xfer_count & 0x7f) <= 0x7f)
749 				xfer_count -= 0x20;
750 		}
751 
752 		desc = txx9dmac_desc_get(dc);
753 		if (!desc) {
754 			txx9dmac_desc_put(dc, first);
755 			return NULL;
756 		}
757 
758 		if (__is_dmac64(ddev)) {
759 			desc->hwdesc.SAR = src + offset;
760 			desc->hwdesc.DAR = dest + offset;
761 			desc->hwdesc.CNTR = xfer_count;
762 			txx9dmac_desc_set_nosimple(ddev, desc, 8, 8,
763 					dc->ccr | TXX9_DMA_CCR_XFACT);
764 		} else {
765 			desc->hwdesc32.SAR = src + offset;
766 			desc->hwdesc32.DAR = dest + offset;
767 			desc->hwdesc32.CNTR = xfer_count;
768 			txx9dmac_desc_set_nosimple(ddev, desc, 4, 4,
769 					dc->ccr | TXX9_DMA_CCR_XFACT);
770 		}
771 
772 		/*
773 		 * The descriptors on tx_list are not reachable from
774 		 * the dc->queue list or dc->active_list after a
775 		 * submit.  If we put all descriptors on active_list,
776 		 * calling of callback on the completion will be more
777 		 * complex.
778 		 */
779 		if (!first) {
780 			first = desc;
781 		} else {
782 			desc_write_CHAR(dc, prev, desc->txd.phys);
783 			dma_sync_single_for_device(chan2parent(&dc->chan),
784 					prev->txd.phys, ddev->descsize,
785 					DMA_TO_DEVICE);
786 			list_add_tail(&desc->desc_node, &first->tx_list);
787 		}
788 		prev = desc;
789 	}
790 
791 	/* Trigger interrupt after last block */
792 	if (flags & DMA_PREP_INTERRUPT)
793 		txx9dmac_desc_set_INTENT(ddev, prev);
794 
795 	desc_write_CHAR(dc, prev, 0);
796 	dma_sync_single_for_device(chan2parent(&dc->chan),
797 			prev->txd.phys, ddev->descsize,
798 			DMA_TO_DEVICE);
799 
800 	first->txd.flags = flags;
801 	first->len = len;
802 
803 	return &first->txd;
804 }
805 
806 static struct dma_async_tx_descriptor *
807 txx9dmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
808 		unsigned int sg_len, enum dma_transfer_direction direction,
809 		unsigned long flags, void *context)
810 {
811 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
812 	struct txx9dmac_dev *ddev = dc->ddev;
813 	struct txx9dmac_slave *ds = chan->private;
814 	struct txx9dmac_desc *prev;
815 	struct txx9dmac_desc *first;
816 	unsigned int i;
817 	struct scatterlist *sg;
818 
819 	dev_vdbg(chan2dev(chan), "prep_dma_slave\n");
820 
821 	BUG_ON(!ds || !ds->reg_width);
822 	if (ds->tx_reg)
823 		BUG_ON(direction != DMA_MEM_TO_DEV);
824 	else
825 		BUG_ON(direction != DMA_DEV_TO_MEM);
826 	if (unlikely(!sg_len))
827 		return NULL;
828 
829 	prev = first = NULL;
830 
831 	for_each_sg(sgl, sg, sg_len, i) {
832 		struct txx9dmac_desc *desc;
833 		dma_addr_t mem;
834 		u32 sai, dai;
835 
836 		desc = txx9dmac_desc_get(dc);
837 		if (!desc) {
838 			txx9dmac_desc_put(dc, first);
839 			return NULL;
840 		}
841 
842 		mem = sg_dma_address(sg);
843 
844 		if (__is_dmac64(ddev)) {
845 			if (direction == DMA_MEM_TO_DEV) {
846 				desc->hwdesc.SAR = mem;
847 				desc->hwdesc.DAR = ds->tx_reg;
848 			} else {
849 				desc->hwdesc.SAR = ds->rx_reg;
850 				desc->hwdesc.DAR = mem;
851 			}
852 			desc->hwdesc.CNTR = sg_dma_len(sg);
853 		} else {
854 			if (direction == DMA_MEM_TO_DEV) {
855 				desc->hwdesc32.SAR = mem;
856 				desc->hwdesc32.DAR = ds->tx_reg;
857 			} else {
858 				desc->hwdesc32.SAR = ds->rx_reg;
859 				desc->hwdesc32.DAR = mem;
860 			}
861 			desc->hwdesc32.CNTR = sg_dma_len(sg);
862 		}
863 		if (direction == DMA_MEM_TO_DEV) {
864 			sai = ds->reg_width;
865 			dai = 0;
866 		} else {
867 			sai = 0;
868 			dai = ds->reg_width;
869 		}
870 		txx9dmac_desc_set_nosimple(ddev, desc, sai, dai,
871 					dc->ccr | TXX9_DMA_CCR_XFACT);
872 
873 		if (!first) {
874 			first = desc;
875 		} else {
876 			desc_write_CHAR(dc, prev, desc->txd.phys);
877 			dma_sync_single_for_device(chan2parent(&dc->chan),
878 					prev->txd.phys,
879 					ddev->descsize,
880 					DMA_TO_DEVICE);
881 			list_add_tail(&desc->desc_node, &first->tx_list);
882 		}
883 		prev = desc;
884 	}
885 
886 	/* Trigger interrupt after last block */
887 	if (flags & DMA_PREP_INTERRUPT)
888 		txx9dmac_desc_set_INTENT(ddev, prev);
889 
890 	desc_write_CHAR(dc, prev, 0);
891 	dma_sync_single_for_device(chan2parent(&dc->chan),
892 			prev->txd.phys, ddev->descsize,
893 			DMA_TO_DEVICE);
894 
895 	first->txd.flags = flags;
896 	first->len = 0;
897 
898 	return &first->txd;
899 }
900 
901 static int txx9dmac_terminate_all(struct dma_chan *chan)
902 {
903 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
904 	struct txx9dmac_desc *desc, *_desc;
905 	LIST_HEAD(list);
906 
907 	dev_vdbg(chan2dev(chan), "terminate_all\n");
908 	spin_lock_bh(&dc->lock);
909 
910 	txx9dmac_reset_chan(dc);
911 
912 	/* active_list entries will end up before queued entries */
913 	list_splice_init(&dc->queue, &list);
914 	list_splice_init(&dc->active_list, &list);
915 
916 	spin_unlock_bh(&dc->lock);
917 
918 	/* Flush all pending and queued descriptors */
919 	list_for_each_entry_safe(desc, _desc, &list, desc_node)
920 		txx9dmac_descriptor_complete(dc, desc);
921 
922 	return 0;
923 }
924 
925 static enum dma_status
926 txx9dmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
927 		   struct dma_tx_state *txstate)
928 {
929 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
930 	enum dma_status ret;
931 
932 	ret = dma_cookie_status(chan, cookie, txstate);
933 	if (ret == DMA_COMPLETE)
934 		return DMA_COMPLETE;
935 
936 	spin_lock_bh(&dc->lock);
937 	txx9dmac_scan_descriptors(dc);
938 	spin_unlock_bh(&dc->lock);
939 
940 	return dma_cookie_status(chan, cookie, txstate);
941 }
942 
943 static void txx9dmac_chain_dynamic(struct txx9dmac_chan *dc,
944 				   struct txx9dmac_desc *prev)
945 {
946 	struct txx9dmac_dev *ddev = dc->ddev;
947 	struct txx9dmac_desc *desc;
948 	LIST_HEAD(list);
949 
950 	prev = txx9dmac_last_child(prev);
951 	txx9dmac_dequeue(dc, &list);
952 	desc = list_entry(list.next, struct txx9dmac_desc, desc_node);
953 	desc_write_CHAR(dc, prev, desc->txd.phys);
954 	dma_sync_single_for_device(chan2parent(&dc->chan),
955 				   prev->txd.phys, ddev->descsize,
956 				   DMA_TO_DEVICE);
957 	mmiowb();
958 	if (!(channel_readl(dc, CSR) & TXX9_DMA_CSR_CHNEN) &&
959 	    channel_read_CHAR(dc) == prev->txd.phys)
960 		/* Restart chain DMA */
961 		channel_write_CHAR(dc, desc->txd.phys);
962 	list_splice_tail(&list, &dc->active_list);
963 }
964 
965 static void txx9dmac_issue_pending(struct dma_chan *chan)
966 {
967 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
968 
969 	spin_lock_bh(&dc->lock);
970 
971 	if (!list_empty(&dc->active_list))
972 		txx9dmac_scan_descriptors(dc);
973 	if (!list_empty(&dc->queue)) {
974 		if (list_empty(&dc->active_list)) {
975 			txx9dmac_dequeue(dc, &dc->active_list);
976 			txx9dmac_dostart(dc, txx9dmac_first_active(dc));
977 		} else if (txx9_dma_have_SMPCHN()) {
978 			struct txx9dmac_desc *prev = txx9dmac_last_active(dc);
979 
980 			if (!(prev->txd.flags & DMA_PREP_INTERRUPT) ||
981 			    txx9dmac_chan_INTENT(dc))
982 				txx9dmac_chain_dynamic(dc, prev);
983 		}
984 	}
985 
986 	spin_unlock_bh(&dc->lock);
987 }
988 
989 static int txx9dmac_alloc_chan_resources(struct dma_chan *chan)
990 {
991 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
992 	struct txx9dmac_slave *ds = chan->private;
993 	struct txx9dmac_desc *desc;
994 	int i;
995 
996 	dev_vdbg(chan2dev(chan), "alloc_chan_resources\n");
997 
998 	/* ASSERT:  channel is idle */
999 	if (channel_readl(dc, CSR) & TXX9_DMA_CSR_XFACT) {
1000 		dev_dbg(chan2dev(chan), "DMA channel not idle?\n");
1001 		return -EIO;
1002 	}
1003 
1004 	dma_cookie_init(chan);
1005 
1006 	dc->ccr = TXX9_DMA_CCR_IMMCHN | TXX9_DMA_CCR_INTENE | CCR_LE;
1007 	txx9dmac_chan_set_SMPCHN(dc);
1008 	if (!txx9_dma_have_SMPCHN() || (dc->ccr & TXX9_DMA_CCR_SMPCHN))
1009 		dc->ccr |= TXX9_DMA_CCR_INTENC;
1010 	if (chan->device->device_prep_dma_memcpy) {
1011 		if (ds)
1012 			return -EINVAL;
1013 		dc->ccr |= TXX9_DMA_CCR_XFSZ_X8;
1014 	} else {
1015 		if (!ds ||
1016 		    (ds->tx_reg && ds->rx_reg) || (!ds->tx_reg && !ds->rx_reg))
1017 			return -EINVAL;
1018 		dc->ccr |= TXX9_DMA_CCR_EXTRQ |
1019 			TXX9_DMA_CCR_XFSZ(__ffs(ds->reg_width));
1020 		txx9dmac_chan_set_INTENT(dc);
1021 	}
1022 
1023 	spin_lock_bh(&dc->lock);
1024 	i = dc->descs_allocated;
1025 	while (dc->descs_allocated < TXX9_DMA_INITIAL_DESC_COUNT) {
1026 		spin_unlock_bh(&dc->lock);
1027 
1028 		desc = txx9dmac_desc_alloc(dc, GFP_KERNEL);
1029 		if (!desc) {
1030 			dev_info(chan2dev(chan),
1031 				"only allocated %d descriptors\n", i);
1032 			spin_lock_bh(&dc->lock);
1033 			break;
1034 		}
1035 		txx9dmac_desc_put(dc, desc);
1036 
1037 		spin_lock_bh(&dc->lock);
1038 		i = ++dc->descs_allocated;
1039 	}
1040 	spin_unlock_bh(&dc->lock);
1041 
1042 	dev_dbg(chan2dev(chan),
1043 		"alloc_chan_resources allocated %d descriptors\n", i);
1044 
1045 	return i;
1046 }
1047 
1048 static void txx9dmac_free_chan_resources(struct dma_chan *chan)
1049 {
1050 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
1051 	struct txx9dmac_dev *ddev = dc->ddev;
1052 	struct txx9dmac_desc *desc, *_desc;
1053 	LIST_HEAD(list);
1054 
1055 	dev_dbg(chan2dev(chan), "free_chan_resources (descs allocated=%u)\n",
1056 			dc->descs_allocated);
1057 
1058 	/* ASSERT:  channel is idle */
1059 	BUG_ON(!list_empty(&dc->active_list));
1060 	BUG_ON(!list_empty(&dc->queue));
1061 	BUG_ON(channel_readl(dc, CSR) & TXX9_DMA_CSR_XFACT);
1062 
1063 	spin_lock_bh(&dc->lock);
1064 	list_splice_init(&dc->free_list, &list);
1065 	dc->descs_allocated = 0;
1066 	spin_unlock_bh(&dc->lock);
1067 
1068 	list_for_each_entry_safe(desc, _desc, &list, desc_node) {
1069 		dev_vdbg(chan2dev(chan), "  freeing descriptor %p\n", desc);
1070 		dma_unmap_single(chan2parent(chan), desc->txd.phys,
1071 				 ddev->descsize, DMA_TO_DEVICE);
1072 		kfree(desc);
1073 	}
1074 
1075 	dev_vdbg(chan2dev(chan), "free_chan_resources done\n");
1076 }
1077 
1078 /*----------------------------------------------------------------------*/
1079 
1080 static void txx9dmac_off(struct txx9dmac_dev *ddev)
1081 {
1082 	dma_writel(ddev, MCR, 0);
1083 	mmiowb();
1084 }
1085 
1086 static int __init txx9dmac_chan_probe(struct platform_device *pdev)
1087 {
1088 	struct txx9dmac_chan_platform_data *cpdata =
1089 			dev_get_platdata(&pdev->dev);
1090 	struct platform_device *dmac_dev = cpdata->dmac_dev;
1091 	struct txx9dmac_platform_data *pdata = dev_get_platdata(&dmac_dev->dev);
1092 	struct txx9dmac_chan *dc;
1093 	int err;
1094 	int ch = pdev->id % TXX9_DMA_MAX_NR_CHANNELS;
1095 	int irq;
1096 
1097 	dc = devm_kzalloc(&pdev->dev, sizeof(*dc), GFP_KERNEL);
1098 	if (!dc)
1099 		return -ENOMEM;
1100 
1101 	dc->dma.dev = &pdev->dev;
1102 	dc->dma.device_alloc_chan_resources = txx9dmac_alloc_chan_resources;
1103 	dc->dma.device_free_chan_resources = txx9dmac_free_chan_resources;
1104 	dc->dma.device_terminate_all = txx9dmac_terminate_all;
1105 	dc->dma.device_tx_status = txx9dmac_tx_status;
1106 	dc->dma.device_issue_pending = txx9dmac_issue_pending;
1107 	if (pdata && pdata->memcpy_chan == ch) {
1108 		dc->dma.device_prep_dma_memcpy = txx9dmac_prep_dma_memcpy;
1109 		dma_cap_set(DMA_MEMCPY, dc->dma.cap_mask);
1110 	} else {
1111 		dc->dma.device_prep_slave_sg = txx9dmac_prep_slave_sg;
1112 		dma_cap_set(DMA_SLAVE, dc->dma.cap_mask);
1113 		dma_cap_set(DMA_PRIVATE, dc->dma.cap_mask);
1114 	}
1115 
1116 	INIT_LIST_HEAD(&dc->dma.channels);
1117 	dc->ddev = platform_get_drvdata(dmac_dev);
1118 	if (dc->ddev->irq < 0) {
1119 		irq = platform_get_irq(pdev, 0);
1120 		if (irq < 0)
1121 			return irq;
1122 		tasklet_init(&dc->tasklet, txx9dmac_chan_tasklet,
1123 				(unsigned long)dc);
1124 		dc->irq = irq;
1125 		err = devm_request_irq(&pdev->dev, dc->irq,
1126 			txx9dmac_chan_interrupt, 0, dev_name(&pdev->dev), dc);
1127 		if (err)
1128 			return err;
1129 	} else
1130 		dc->irq = -1;
1131 	dc->ddev->chan[ch] = dc;
1132 	dc->chan.device = &dc->dma;
1133 	list_add_tail(&dc->chan.device_node, &dc->chan.device->channels);
1134 	dma_cookie_init(&dc->chan);
1135 
1136 	if (is_dmac64(dc))
1137 		dc->ch_regs = &__txx9dmac_regs(dc->ddev)->CHAN[ch];
1138 	else
1139 		dc->ch_regs = &__txx9dmac_regs32(dc->ddev)->CHAN[ch];
1140 	spin_lock_init(&dc->lock);
1141 
1142 	INIT_LIST_HEAD(&dc->active_list);
1143 	INIT_LIST_HEAD(&dc->queue);
1144 	INIT_LIST_HEAD(&dc->free_list);
1145 
1146 	txx9dmac_reset_chan(dc);
1147 
1148 	platform_set_drvdata(pdev, dc);
1149 
1150 	err = dma_async_device_register(&dc->dma);
1151 	if (err)
1152 		return err;
1153 	dev_dbg(&pdev->dev, "TXx9 DMA Channel (dma%d%s%s)\n",
1154 		dc->dma.dev_id,
1155 		dma_has_cap(DMA_MEMCPY, dc->dma.cap_mask) ? " memcpy" : "",
1156 		dma_has_cap(DMA_SLAVE, dc->dma.cap_mask) ? " slave" : "");
1157 
1158 	return 0;
1159 }
1160 
1161 static int txx9dmac_chan_remove(struct platform_device *pdev)
1162 {
1163 	struct txx9dmac_chan *dc = platform_get_drvdata(pdev);
1164 
1165 
1166 	dma_async_device_unregister(&dc->dma);
1167 	if (dc->irq >= 0) {
1168 		devm_free_irq(&pdev->dev, dc->irq, dc);
1169 		tasklet_kill(&dc->tasklet);
1170 	}
1171 	dc->ddev->chan[pdev->id % TXX9_DMA_MAX_NR_CHANNELS] = NULL;
1172 	return 0;
1173 }
1174 
1175 static int __init txx9dmac_probe(struct platform_device *pdev)
1176 {
1177 	struct txx9dmac_platform_data *pdata = dev_get_platdata(&pdev->dev);
1178 	struct resource *io;
1179 	struct txx9dmac_dev *ddev;
1180 	u32 mcr;
1181 	int err;
1182 
1183 	io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1184 	if (!io)
1185 		return -EINVAL;
1186 
1187 	ddev = devm_kzalloc(&pdev->dev, sizeof(*ddev), GFP_KERNEL);
1188 	if (!ddev)
1189 		return -ENOMEM;
1190 
1191 	if (!devm_request_mem_region(&pdev->dev, io->start, resource_size(io),
1192 				     dev_name(&pdev->dev)))
1193 		return -EBUSY;
1194 
1195 	ddev->regs = devm_ioremap(&pdev->dev, io->start, resource_size(io));
1196 	if (!ddev->regs)
1197 		return -ENOMEM;
1198 	ddev->have_64bit_regs = pdata->have_64bit_regs;
1199 	if (__is_dmac64(ddev))
1200 		ddev->descsize = sizeof(struct txx9dmac_hwdesc);
1201 	else
1202 		ddev->descsize = sizeof(struct txx9dmac_hwdesc32);
1203 
1204 	/* force dma off, just in case */
1205 	txx9dmac_off(ddev);
1206 
1207 	ddev->irq = platform_get_irq(pdev, 0);
1208 	if (ddev->irq >= 0) {
1209 		tasklet_init(&ddev->tasklet, txx9dmac_tasklet,
1210 				(unsigned long)ddev);
1211 		err = devm_request_irq(&pdev->dev, ddev->irq,
1212 			txx9dmac_interrupt, 0, dev_name(&pdev->dev), ddev);
1213 		if (err)
1214 			return err;
1215 	}
1216 
1217 	mcr = TXX9_DMA_MCR_MSTEN | MCR_LE;
1218 	if (pdata && pdata->memcpy_chan >= 0)
1219 		mcr |= TXX9_DMA_MCR_FIFUM(pdata->memcpy_chan);
1220 	dma_writel(ddev, MCR, mcr);
1221 
1222 	platform_set_drvdata(pdev, ddev);
1223 	return 0;
1224 }
1225 
1226 static int txx9dmac_remove(struct platform_device *pdev)
1227 {
1228 	struct txx9dmac_dev *ddev = platform_get_drvdata(pdev);
1229 
1230 	txx9dmac_off(ddev);
1231 	if (ddev->irq >= 0) {
1232 		devm_free_irq(&pdev->dev, ddev->irq, ddev);
1233 		tasklet_kill(&ddev->tasklet);
1234 	}
1235 	return 0;
1236 }
1237 
1238 static void txx9dmac_shutdown(struct platform_device *pdev)
1239 {
1240 	struct txx9dmac_dev *ddev = platform_get_drvdata(pdev);
1241 
1242 	txx9dmac_off(ddev);
1243 }
1244 
1245 static int txx9dmac_suspend_noirq(struct device *dev)
1246 {
1247 	struct txx9dmac_dev *ddev = dev_get_drvdata(dev);
1248 
1249 	txx9dmac_off(ddev);
1250 	return 0;
1251 }
1252 
1253 static int txx9dmac_resume_noirq(struct device *dev)
1254 {
1255 	struct txx9dmac_dev *ddev = dev_get_drvdata(dev);
1256 	struct txx9dmac_platform_data *pdata = dev_get_platdata(dev);
1257 	u32 mcr;
1258 
1259 	mcr = TXX9_DMA_MCR_MSTEN | MCR_LE;
1260 	if (pdata && pdata->memcpy_chan >= 0)
1261 		mcr |= TXX9_DMA_MCR_FIFUM(pdata->memcpy_chan);
1262 	dma_writel(ddev, MCR, mcr);
1263 	return 0;
1264 
1265 }
1266 
1267 static const struct dev_pm_ops txx9dmac_dev_pm_ops = {
1268 	.suspend_noirq = txx9dmac_suspend_noirq,
1269 	.resume_noirq = txx9dmac_resume_noirq,
1270 };
1271 
1272 static struct platform_driver txx9dmac_chan_driver = {
1273 	.remove		= txx9dmac_chan_remove,
1274 	.driver = {
1275 		.name	= "txx9dmac-chan",
1276 	},
1277 };
1278 
1279 static struct platform_driver txx9dmac_driver = {
1280 	.remove		= txx9dmac_remove,
1281 	.shutdown	= txx9dmac_shutdown,
1282 	.driver = {
1283 		.name	= "txx9dmac",
1284 		.pm	= &txx9dmac_dev_pm_ops,
1285 	},
1286 };
1287 
1288 static int __init txx9dmac_init(void)
1289 {
1290 	int rc;
1291 
1292 	rc = platform_driver_probe(&txx9dmac_driver, txx9dmac_probe);
1293 	if (!rc) {
1294 		rc = platform_driver_probe(&txx9dmac_chan_driver,
1295 					   txx9dmac_chan_probe);
1296 		if (rc)
1297 			platform_driver_unregister(&txx9dmac_driver);
1298 	}
1299 	return rc;
1300 }
1301 module_init(txx9dmac_init);
1302 
1303 static void __exit txx9dmac_exit(void)
1304 {
1305 	platform_driver_unregister(&txx9dmac_chan_driver);
1306 	platform_driver_unregister(&txx9dmac_driver);
1307 }
1308 module_exit(txx9dmac_exit);
1309 
1310 MODULE_LICENSE("GPL");
1311 MODULE_DESCRIPTION("TXx9 DMA Controller driver");
1312 MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
1313 MODULE_ALIAS("platform:txx9dmac");
1314 MODULE_ALIAS("platform:txx9dmac-chan");
1315