xref: /linux/drivers/dma/idma64.c (revision b4ba157044ea433a66126603ad7140e12dbc794b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Core driver for the Intel integrated DMA 64-bit
4  *
5  * Copyright (C) 2015 Intel Corporation
6  * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
7  */
8 
9 #include <linux/bitops.h>
10 #include <linux/delay.h>
11 #include <linux/dmaengine.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/dmapool.h>
14 #include <linux/init.h>
15 #include <linux/module.h>
16 #include <linux/platform_device.h>
17 #include <linux/slab.h>
18 
19 #include <linux/dma/idma64.h>
20 
21 #include "idma64.h"
22 
23 /* For now we support only two channels */
24 #define IDMA64_NR_CHAN		2
25 
26 /* ---------------------------------------------------------------------- */
27 
28 static struct device *chan2dev(struct dma_chan *chan)
29 {
30 	return &chan->dev->device;
31 }
32 
33 /* ---------------------------------------------------------------------- */
34 
35 static void idma64_off(struct idma64 *idma64)
36 {
37 	unsigned short count = 100;
38 
39 	dma_writel(idma64, CFG, 0);
40 
41 	channel_clear_bit(idma64, MASK(XFER), idma64->all_chan_mask);
42 	channel_clear_bit(idma64, MASK(BLOCK), idma64->all_chan_mask);
43 	channel_clear_bit(idma64, MASK(SRC_TRAN), idma64->all_chan_mask);
44 	channel_clear_bit(idma64, MASK(DST_TRAN), idma64->all_chan_mask);
45 	channel_clear_bit(idma64, MASK(ERROR), idma64->all_chan_mask);
46 
47 	do {
48 		cpu_relax();
49 	} while (dma_readl(idma64, CFG) & IDMA64_CFG_DMA_EN && --count);
50 }
51 
52 static void idma64_on(struct idma64 *idma64)
53 {
54 	dma_writel(idma64, CFG, IDMA64_CFG_DMA_EN);
55 }
56 
57 /* ---------------------------------------------------------------------- */
58 
59 static void idma64_chan_init(struct idma64 *idma64, struct idma64_chan *idma64c)
60 {
61 	u32 cfghi = IDMA64C_CFGH_SRC_PER(1) | IDMA64C_CFGH_DST_PER(0);
62 	u32 cfglo = 0;
63 
64 	/* Set default burst alignment */
65 	cfglo |= IDMA64C_CFGL_DST_BURST_ALIGN | IDMA64C_CFGL_SRC_BURST_ALIGN;
66 
67 	channel_writel(idma64c, CFG_LO, cfglo);
68 	channel_writel(idma64c, CFG_HI, cfghi);
69 
70 	/* Enable interrupts */
71 	channel_set_bit(idma64, MASK(XFER), idma64c->mask);
72 	channel_set_bit(idma64, MASK(ERROR), idma64c->mask);
73 
74 	/*
75 	 * Enforce the controller to be turned on.
76 	 *
77 	 * The iDMA is turned off in ->probe() and looses context during system
78 	 * suspend / resume cycle. That's why we have to enable it each time we
79 	 * use it.
80 	 */
81 	idma64_on(idma64);
82 }
83 
84 static void idma64_chan_stop(struct idma64 *idma64, struct idma64_chan *idma64c)
85 {
86 	channel_clear_bit(idma64, CH_EN, idma64c->mask);
87 }
88 
89 static void idma64_chan_start(struct idma64 *idma64, struct idma64_chan *idma64c)
90 {
91 	struct idma64_desc *desc = idma64c->desc;
92 	struct idma64_hw_desc *hw = &desc->hw[0];
93 
94 	channel_writeq(idma64c, SAR, 0);
95 	channel_writeq(idma64c, DAR, 0);
96 
97 	channel_writel(idma64c, CTL_HI, IDMA64C_CTLH_BLOCK_TS(~0UL));
98 	channel_writel(idma64c, CTL_LO, IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN);
99 
100 	channel_writeq(idma64c, LLP, hw->llp);
101 
102 	channel_set_bit(idma64, CH_EN, idma64c->mask);
103 }
104 
105 static void idma64_stop_transfer(struct idma64_chan *idma64c)
106 {
107 	struct idma64 *idma64 = to_idma64(idma64c->vchan.chan.device);
108 
109 	idma64_chan_stop(idma64, idma64c);
110 }
111 
112 static void idma64_start_transfer(struct idma64_chan *idma64c)
113 {
114 	struct idma64 *idma64 = to_idma64(idma64c->vchan.chan.device);
115 	struct virt_dma_desc *vdesc;
116 
117 	/* Get the next descriptor */
118 	vdesc = vchan_next_desc(&idma64c->vchan);
119 	if (!vdesc) {
120 		idma64c->desc = NULL;
121 		return;
122 	}
123 
124 	list_del(&vdesc->node);
125 	idma64c->desc = to_idma64_desc(vdesc);
126 
127 	/* Configure the channel */
128 	idma64_chan_init(idma64, idma64c);
129 
130 	/* Start the channel with a new descriptor */
131 	idma64_chan_start(idma64, idma64c);
132 }
133 
134 /* ---------------------------------------------------------------------- */
135 
136 static void idma64_chan_irq(struct idma64 *idma64, unsigned short c,
137 		u32 status_err, u32 status_xfer)
138 {
139 	struct idma64_chan *idma64c = &idma64->chan[c];
140 	struct dma_chan_percpu *stat;
141 	struct idma64_desc *desc;
142 
143 	stat = this_cpu_ptr(idma64c->vchan.chan.local);
144 
145 	spin_lock(&idma64c->vchan.lock);
146 	desc = idma64c->desc;
147 	if (desc) {
148 		if (status_err & (1 << c)) {
149 			dma_writel(idma64, CLEAR(ERROR), idma64c->mask);
150 			desc->status = DMA_ERROR;
151 		} else if (status_xfer & (1 << c)) {
152 			dma_writel(idma64, CLEAR(XFER), idma64c->mask);
153 			desc->status = DMA_COMPLETE;
154 			vchan_cookie_complete(&desc->vdesc);
155 			stat->bytes_transferred += desc->length;
156 			idma64_start_transfer(idma64c);
157 		}
158 
159 		/* idma64_start_transfer() updates idma64c->desc */
160 		if (idma64c->desc == NULL || desc->status == DMA_ERROR)
161 			idma64_stop_transfer(idma64c);
162 	}
163 	spin_unlock(&idma64c->vchan.lock);
164 }
165 
166 static irqreturn_t idma64_irq(int irq, void *dev)
167 {
168 	struct idma64 *idma64 = dev;
169 	u32 status = dma_readl(idma64, STATUS_INT);
170 	u32 status_xfer;
171 	u32 status_err;
172 	unsigned short i;
173 
174 	/* Since IRQ may be shared, check if DMA controller is powered on */
175 	if (status == GENMASK(31, 0))
176 		return IRQ_NONE;
177 
178 	dev_vdbg(idma64->dma.dev, "%s: status=%#x\n", __func__, status);
179 
180 	/* Check if we have any interrupt from the DMA controller */
181 	if (!status)
182 		return IRQ_NONE;
183 
184 	status_xfer = dma_readl(idma64, RAW(XFER));
185 	status_err = dma_readl(idma64, RAW(ERROR));
186 
187 	for (i = 0; i < idma64->dma.chancnt; i++)
188 		idma64_chan_irq(idma64, i, status_err, status_xfer);
189 
190 	return IRQ_HANDLED;
191 }
192 
193 /* ---------------------------------------------------------------------- */
194 
195 static struct idma64_desc *idma64_alloc_desc(unsigned int ndesc)
196 {
197 	struct idma64_desc *desc;
198 
199 	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
200 	if (!desc)
201 		return NULL;
202 
203 	desc->hw = kcalloc(ndesc, sizeof(*desc->hw), GFP_NOWAIT);
204 	if (!desc->hw) {
205 		kfree(desc);
206 		return NULL;
207 	}
208 
209 	return desc;
210 }
211 
212 static void idma64_desc_free(struct idma64_chan *idma64c,
213 		struct idma64_desc *desc)
214 {
215 	struct idma64_hw_desc *hw;
216 
217 	if (desc->ndesc) {
218 		unsigned int i = desc->ndesc;
219 
220 		do {
221 			hw = &desc->hw[--i];
222 			dma_pool_free(idma64c->pool, hw->lli, hw->llp);
223 		} while (i);
224 	}
225 
226 	kfree(desc->hw);
227 	kfree(desc);
228 }
229 
230 static void idma64_vdesc_free(struct virt_dma_desc *vdesc)
231 {
232 	struct idma64_chan *idma64c = to_idma64_chan(vdesc->tx.chan);
233 
234 	idma64_desc_free(idma64c, to_idma64_desc(vdesc));
235 }
236 
237 static void idma64_hw_desc_fill(struct idma64_hw_desc *hw,
238 		struct dma_slave_config *config,
239 		enum dma_transfer_direction direction, u64 llp)
240 {
241 	struct idma64_lli *lli = hw->lli;
242 	u64 sar, dar;
243 	u32 ctlhi = IDMA64C_CTLH_BLOCK_TS(hw->len);
244 	u32 ctllo = IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN;
245 	u32 src_width, dst_width;
246 
247 	if (direction == DMA_MEM_TO_DEV) {
248 		sar = hw->phys;
249 		dar = config->dst_addr;
250 		ctllo |= IDMA64C_CTLL_DST_FIX | IDMA64C_CTLL_SRC_INC |
251 			 IDMA64C_CTLL_FC_M2P;
252 		src_width = __ffs(sar | hw->len | 4);
253 		dst_width = __ffs(config->dst_addr_width);
254 	} else {	/* DMA_DEV_TO_MEM */
255 		sar = config->src_addr;
256 		dar = hw->phys;
257 		ctllo |= IDMA64C_CTLL_DST_INC | IDMA64C_CTLL_SRC_FIX |
258 			 IDMA64C_CTLL_FC_P2M;
259 		src_width = __ffs(config->src_addr_width);
260 		dst_width = __ffs(dar | hw->len | 4);
261 	}
262 
263 	lli->sar = sar;
264 	lli->dar = dar;
265 
266 	lli->ctlhi = ctlhi;
267 	lli->ctllo = ctllo |
268 		     IDMA64C_CTLL_SRC_MSIZE(config->src_maxburst) |
269 		     IDMA64C_CTLL_DST_MSIZE(config->dst_maxburst) |
270 		     IDMA64C_CTLL_DST_WIDTH(dst_width) |
271 		     IDMA64C_CTLL_SRC_WIDTH(src_width);
272 
273 	lli->llp = llp;
274 }
275 
276 static void idma64_desc_fill(struct idma64_chan *idma64c,
277 		struct idma64_desc *desc)
278 {
279 	struct dma_slave_config *config = &idma64c->config;
280 	unsigned int i = desc->ndesc;
281 	struct idma64_hw_desc *hw = &desc->hw[i - 1];
282 	struct idma64_lli *lli = hw->lli;
283 	u64 llp = 0;
284 
285 	/* Fill the hardware descriptors and link them to a list */
286 	do {
287 		hw = &desc->hw[--i];
288 		idma64_hw_desc_fill(hw, config, desc->direction, llp);
289 		llp = hw->llp;
290 		desc->length += hw->len;
291 	} while (i);
292 
293 	/* Trigger an interrupt after the last block is transfered */
294 	lli->ctllo |= IDMA64C_CTLL_INT_EN;
295 
296 	/* Disable LLP transfer in the last block */
297 	lli->ctllo &= ~(IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN);
298 }
299 
300 static struct dma_async_tx_descriptor *idma64_prep_slave_sg(
301 		struct dma_chan *chan, struct scatterlist *sgl,
302 		unsigned int sg_len, enum dma_transfer_direction direction,
303 		unsigned long flags, void *context)
304 {
305 	struct idma64_chan *idma64c = to_idma64_chan(chan);
306 	struct idma64_desc *desc;
307 	struct scatterlist *sg;
308 	unsigned int i;
309 
310 	desc = idma64_alloc_desc(sg_len);
311 	if (!desc)
312 		return NULL;
313 
314 	for_each_sg(sgl, sg, sg_len, i) {
315 		struct idma64_hw_desc *hw = &desc->hw[i];
316 
317 		/* Allocate DMA capable memory for hardware descriptor */
318 		hw->lli = dma_pool_alloc(idma64c->pool, GFP_NOWAIT, &hw->llp);
319 		if (!hw->lli) {
320 			desc->ndesc = i;
321 			idma64_desc_free(idma64c, desc);
322 			return NULL;
323 		}
324 
325 		hw->phys = sg_dma_address(sg);
326 		hw->len = sg_dma_len(sg);
327 	}
328 
329 	desc->ndesc = sg_len;
330 	desc->direction = direction;
331 	desc->status = DMA_IN_PROGRESS;
332 
333 	idma64_desc_fill(idma64c, desc);
334 	return vchan_tx_prep(&idma64c->vchan, &desc->vdesc, flags);
335 }
336 
337 static void idma64_issue_pending(struct dma_chan *chan)
338 {
339 	struct idma64_chan *idma64c = to_idma64_chan(chan);
340 	unsigned long flags;
341 
342 	spin_lock_irqsave(&idma64c->vchan.lock, flags);
343 	if (vchan_issue_pending(&idma64c->vchan) && !idma64c->desc)
344 		idma64_start_transfer(idma64c);
345 	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
346 }
347 
348 static size_t idma64_active_desc_size(struct idma64_chan *idma64c)
349 {
350 	struct idma64_desc *desc = idma64c->desc;
351 	struct idma64_hw_desc *hw;
352 	size_t bytes = desc->length;
353 	u64 llp = channel_readq(idma64c, LLP);
354 	u32 ctlhi = channel_readl(idma64c, CTL_HI);
355 	unsigned int i = 0;
356 
357 	do {
358 		hw = &desc->hw[i];
359 		if (hw->llp == llp)
360 			break;
361 		bytes -= hw->len;
362 	} while (++i < desc->ndesc);
363 
364 	if (!i)
365 		return bytes;
366 
367 	/* The current chunk is not fully transfered yet */
368 	bytes += desc->hw[--i].len;
369 
370 	return bytes - IDMA64C_CTLH_BLOCK_TS(ctlhi);
371 }
372 
373 static enum dma_status idma64_tx_status(struct dma_chan *chan,
374 		dma_cookie_t cookie, struct dma_tx_state *state)
375 {
376 	struct idma64_chan *idma64c = to_idma64_chan(chan);
377 	struct virt_dma_desc *vdesc;
378 	enum dma_status status;
379 	size_t bytes;
380 	unsigned long flags;
381 
382 	status = dma_cookie_status(chan, cookie, state);
383 	if (status == DMA_COMPLETE)
384 		return status;
385 
386 	spin_lock_irqsave(&idma64c->vchan.lock, flags);
387 	vdesc = vchan_find_desc(&idma64c->vchan, cookie);
388 	if (idma64c->desc && cookie == idma64c->desc->vdesc.tx.cookie) {
389 		bytes = idma64_active_desc_size(idma64c);
390 		dma_set_residue(state, bytes);
391 		status = idma64c->desc->status;
392 	} else if (vdesc) {
393 		bytes = to_idma64_desc(vdesc)->length;
394 		dma_set_residue(state, bytes);
395 	}
396 	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
397 
398 	return status;
399 }
400 
401 static void convert_burst(u32 *maxburst)
402 {
403 	if (*maxburst)
404 		*maxburst = __fls(*maxburst);
405 	else
406 		*maxburst = 0;
407 }
408 
409 static int idma64_slave_config(struct dma_chan *chan,
410 		struct dma_slave_config *config)
411 {
412 	struct idma64_chan *idma64c = to_idma64_chan(chan);
413 
414 	memcpy(&idma64c->config, config, sizeof(idma64c->config));
415 
416 	convert_burst(&idma64c->config.src_maxburst);
417 	convert_burst(&idma64c->config.dst_maxburst);
418 
419 	return 0;
420 }
421 
422 static void idma64_chan_deactivate(struct idma64_chan *idma64c, bool drain)
423 {
424 	unsigned short count = 100;
425 	u32 cfglo;
426 
427 	cfglo = channel_readl(idma64c, CFG_LO);
428 	if (drain)
429 		cfglo |= IDMA64C_CFGL_CH_DRAIN;
430 	else
431 		cfglo &= ~IDMA64C_CFGL_CH_DRAIN;
432 
433 	channel_writel(idma64c, CFG_LO, cfglo | IDMA64C_CFGL_CH_SUSP);
434 	do {
435 		udelay(1);
436 		cfglo = channel_readl(idma64c, CFG_LO);
437 	} while (!(cfglo & IDMA64C_CFGL_FIFO_EMPTY) && --count);
438 }
439 
440 static void idma64_chan_activate(struct idma64_chan *idma64c)
441 {
442 	u32 cfglo;
443 
444 	cfglo = channel_readl(idma64c, CFG_LO);
445 	channel_writel(idma64c, CFG_LO, cfglo & ~IDMA64C_CFGL_CH_SUSP);
446 }
447 
448 static int idma64_pause(struct dma_chan *chan)
449 {
450 	struct idma64_chan *idma64c = to_idma64_chan(chan);
451 	unsigned long flags;
452 
453 	spin_lock_irqsave(&idma64c->vchan.lock, flags);
454 	if (idma64c->desc && idma64c->desc->status == DMA_IN_PROGRESS) {
455 		idma64_chan_deactivate(idma64c, false);
456 		idma64c->desc->status = DMA_PAUSED;
457 	}
458 	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
459 
460 	return 0;
461 }
462 
463 static int idma64_resume(struct dma_chan *chan)
464 {
465 	struct idma64_chan *idma64c = to_idma64_chan(chan);
466 	unsigned long flags;
467 
468 	spin_lock_irqsave(&idma64c->vchan.lock, flags);
469 	if (idma64c->desc && idma64c->desc->status == DMA_PAUSED) {
470 		idma64c->desc->status = DMA_IN_PROGRESS;
471 		idma64_chan_activate(idma64c);
472 	}
473 	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
474 
475 	return 0;
476 }
477 
478 static int idma64_terminate_all(struct dma_chan *chan)
479 {
480 	struct idma64_chan *idma64c = to_idma64_chan(chan);
481 	unsigned long flags;
482 	LIST_HEAD(head);
483 
484 	spin_lock_irqsave(&idma64c->vchan.lock, flags);
485 	idma64_chan_deactivate(idma64c, true);
486 	idma64_stop_transfer(idma64c);
487 	if (idma64c->desc) {
488 		idma64_vdesc_free(&idma64c->desc->vdesc);
489 		idma64c->desc = NULL;
490 	}
491 	vchan_get_all_descriptors(&idma64c->vchan, &head);
492 	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
493 
494 	vchan_dma_desc_free_list(&idma64c->vchan, &head);
495 	return 0;
496 }
497 
498 static void idma64_synchronize(struct dma_chan *chan)
499 {
500 	struct idma64_chan *idma64c = to_idma64_chan(chan);
501 
502 	vchan_synchronize(&idma64c->vchan);
503 }
504 
505 static int idma64_alloc_chan_resources(struct dma_chan *chan)
506 {
507 	struct idma64_chan *idma64c = to_idma64_chan(chan);
508 
509 	/* Create a pool of consistent memory blocks for hardware descriptors */
510 	idma64c->pool = dma_pool_create(dev_name(chan2dev(chan)),
511 					chan->device->dev,
512 					sizeof(struct idma64_lli), 8, 0);
513 	if (!idma64c->pool) {
514 		dev_err(chan2dev(chan), "No memory for descriptors\n");
515 		return -ENOMEM;
516 	}
517 
518 	return 0;
519 }
520 
521 static void idma64_free_chan_resources(struct dma_chan *chan)
522 {
523 	struct idma64_chan *idma64c = to_idma64_chan(chan);
524 
525 	vchan_free_chan_resources(to_virt_chan(chan));
526 	dma_pool_destroy(idma64c->pool);
527 	idma64c->pool = NULL;
528 }
529 
530 /* ---------------------------------------------------------------------- */
531 
532 #define IDMA64_BUSWIDTHS				\
533 	BIT(DMA_SLAVE_BUSWIDTH_1_BYTE)		|	\
534 	BIT(DMA_SLAVE_BUSWIDTH_2_BYTES)		|	\
535 	BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)
536 
537 static int idma64_probe(struct idma64_chip *chip)
538 {
539 	struct idma64 *idma64;
540 	unsigned short nr_chan = IDMA64_NR_CHAN;
541 	unsigned short i;
542 	int ret;
543 
544 	idma64 = devm_kzalloc(chip->dev, sizeof(*idma64), GFP_KERNEL);
545 	if (!idma64)
546 		return -ENOMEM;
547 
548 	idma64->regs = chip->regs;
549 	chip->idma64 = idma64;
550 
551 	idma64->chan = devm_kcalloc(chip->dev, nr_chan, sizeof(*idma64->chan),
552 				    GFP_KERNEL);
553 	if (!idma64->chan)
554 		return -ENOMEM;
555 
556 	idma64->all_chan_mask = (1 << nr_chan) - 1;
557 
558 	/* Turn off iDMA controller */
559 	idma64_off(idma64);
560 
561 	ret = devm_request_irq(chip->dev, chip->irq, idma64_irq, IRQF_SHARED,
562 			       dev_name(chip->dev), idma64);
563 	if (ret)
564 		return ret;
565 
566 	INIT_LIST_HEAD(&idma64->dma.channels);
567 	for (i = 0; i < nr_chan; i++) {
568 		struct idma64_chan *idma64c = &idma64->chan[i];
569 
570 		idma64c->vchan.desc_free = idma64_vdesc_free;
571 		vchan_init(&idma64c->vchan, &idma64->dma);
572 
573 		idma64c->regs = idma64->regs + i * IDMA64_CH_LENGTH;
574 		idma64c->mask = BIT(i);
575 	}
576 
577 	dma_cap_set(DMA_SLAVE, idma64->dma.cap_mask);
578 	dma_cap_set(DMA_PRIVATE, idma64->dma.cap_mask);
579 
580 	idma64->dma.device_alloc_chan_resources = idma64_alloc_chan_resources;
581 	idma64->dma.device_free_chan_resources = idma64_free_chan_resources;
582 
583 	idma64->dma.device_prep_slave_sg = idma64_prep_slave_sg;
584 
585 	idma64->dma.device_issue_pending = idma64_issue_pending;
586 	idma64->dma.device_tx_status = idma64_tx_status;
587 
588 	idma64->dma.device_config = idma64_slave_config;
589 	idma64->dma.device_pause = idma64_pause;
590 	idma64->dma.device_resume = idma64_resume;
591 	idma64->dma.device_terminate_all = idma64_terminate_all;
592 	idma64->dma.device_synchronize = idma64_synchronize;
593 
594 	idma64->dma.src_addr_widths = IDMA64_BUSWIDTHS;
595 	idma64->dma.dst_addr_widths = IDMA64_BUSWIDTHS;
596 	idma64->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
597 	idma64->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
598 
599 	idma64->dma.dev = chip->sysdev;
600 
601 	ret = dma_set_max_seg_size(idma64->dma.dev, IDMA64C_CTLH_BLOCK_TS_MASK);
602 	if (ret)
603 		return ret;
604 
605 	ret = dma_async_device_register(&idma64->dma);
606 	if (ret)
607 		return ret;
608 
609 	dev_info(chip->dev, "Found Intel integrated DMA 64-bit\n");
610 	return 0;
611 }
612 
613 static void idma64_remove(struct idma64_chip *chip)
614 {
615 	struct idma64 *idma64 = chip->idma64;
616 	unsigned short i;
617 
618 	dma_async_device_unregister(&idma64->dma);
619 
620 	/*
621 	 * Explicitly call devm_request_irq() to avoid the side effects with
622 	 * the scheduled tasklets.
623 	 */
624 	devm_free_irq(chip->dev, chip->irq, idma64);
625 
626 	for (i = 0; i < idma64->dma.chancnt; i++) {
627 		struct idma64_chan *idma64c = &idma64->chan[i];
628 
629 		tasklet_kill(&idma64c->vchan.task);
630 	}
631 }
632 
633 /* ---------------------------------------------------------------------- */
634 
635 static int idma64_platform_probe(struct platform_device *pdev)
636 {
637 	struct idma64_chip *chip;
638 	struct device *dev = &pdev->dev;
639 	struct device *sysdev = dev->parent;
640 	int ret;
641 
642 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
643 	if (!chip)
644 		return -ENOMEM;
645 
646 	chip->irq = platform_get_irq(pdev, 0);
647 	if (chip->irq < 0)
648 		return chip->irq;
649 
650 	chip->regs = devm_platform_ioremap_resource(pdev, 0);
651 	if (IS_ERR(chip->regs))
652 		return PTR_ERR(chip->regs);
653 
654 	ret = dma_coerce_mask_and_coherent(sysdev, DMA_BIT_MASK(64));
655 	if (ret)
656 		return ret;
657 
658 	chip->dev = dev;
659 	chip->sysdev = sysdev;
660 
661 	ret = idma64_probe(chip);
662 	if (ret)
663 		return ret;
664 
665 	platform_set_drvdata(pdev, chip);
666 	return 0;
667 }
668 
669 static void idma64_platform_remove(struct platform_device *pdev)
670 {
671 	struct idma64_chip *chip = platform_get_drvdata(pdev);
672 
673 	idma64_remove(chip);
674 }
675 
676 static int __maybe_unused idma64_pm_suspend(struct device *dev)
677 {
678 	struct idma64_chip *chip = dev_get_drvdata(dev);
679 
680 	idma64_off(chip->idma64);
681 	return 0;
682 }
683 
684 static int __maybe_unused idma64_pm_resume(struct device *dev)
685 {
686 	struct idma64_chip *chip = dev_get_drvdata(dev);
687 
688 	idma64_on(chip->idma64);
689 	return 0;
690 }
691 
692 static const struct dev_pm_ops idma64_dev_pm_ops = {
693 	SET_SYSTEM_SLEEP_PM_OPS(idma64_pm_suspend, idma64_pm_resume)
694 };
695 
696 static struct platform_driver idma64_platform_driver = {
697 	.probe		= idma64_platform_probe,
698 	.remove_new	= idma64_platform_remove,
699 	.driver = {
700 		.name	= LPSS_IDMA64_DRIVER_NAME,
701 		.pm	= &idma64_dev_pm_ops,
702 	},
703 };
704 
705 module_platform_driver(idma64_platform_driver);
706 
707 MODULE_LICENSE("GPL v2");
708 MODULE_DESCRIPTION("iDMA64 core driver");
709 MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
710 MODULE_ALIAS("platform:" LPSS_IDMA64_DRIVER_NAME);
711