xref: /openbmc/linux/drivers/dma/idma64.c (revision adb57164) 
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 idma64_desc *desc;
141 
142 	spin_lock(&idma64c->vchan.lock);
143 	desc = idma64c->desc;
144 	if (desc) {
145 		if (status_err & (1 << c)) {
146 			dma_writel(idma64, CLEAR(ERROR), idma64c->mask);
147 			desc->status = DMA_ERROR;
148 		} else if (status_xfer & (1 << c)) {
149 			dma_writel(idma64, CLEAR(XFER), idma64c->mask);
150 			desc->status = DMA_COMPLETE;
151 			vchan_cookie_complete(&desc->vdesc);
152 			idma64_start_transfer(idma64c);
153 		}
154 
155 		/* idma64_start_transfer() updates idma64c->desc */
156 		if (idma64c->desc == NULL || desc->status == DMA_ERROR)
157 			idma64_stop_transfer(idma64c);
158 	}
159 	spin_unlock(&idma64c->vchan.lock);
160 }
161 
162 static irqreturn_t idma64_irq(int irq, void *dev)
163 {
164 	struct idma64 *idma64 = dev;
165 	u32 status = dma_readl(idma64, STATUS_INT);
166 	u32 status_xfer;
167 	u32 status_err;
168 	unsigned short i;
169 
170 	dev_vdbg(idma64->dma.dev, "%s: status=%#x\n", __func__, status);
171 
172 	/* Check if we have any interrupt from the DMA controller */
173 	if (!status)
174 		return IRQ_NONE;
175 
176 	status_xfer = dma_readl(idma64, RAW(XFER));
177 	status_err = dma_readl(idma64, RAW(ERROR));
178 
179 	for (i = 0; i < idma64->dma.chancnt; i++)
180 		idma64_chan_irq(idma64, i, status_err, status_xfer);
181 
182 	return IRQ_HANDLED;
183 }
184 
185 /* ---------------------------------------------------------------------- */
186 
187 static struct idma64_desc *idma64_alloc_desc(unsigned int ndesc)
188 {
189 	struct idma64_desc *desc;
190 
191 	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
192 	if (!desc)
193 		return NULL;
194 
195 	desc->hw = kcalloc(ndesc, sizeof(*desc->hw), GFP_NOWAIT);
196 	if (!desc->hw) {
197 		kfree(desc);
198 		return NULL;
199 	}
200 
201 	return desc;
202 }
203 
204 static void idma64_desc_free(struct idma64_chan *idma64c,
205 		struct idma64_desc *desc)
206 {
207 	struct idma64_hw_desc *hw;
208 
209 	if (desc->ndesc) {
210 		unsigned int i = desc->ndesc;
211 
212 		do {
213 			hw = &desc->hw[--i];
214 			dma_pool_free(idma64c->pool, hw->lli, hw->llp);
215 		} while (i);
216 	}
217 
218 	kfree(desc->hw);
219 	kfree(desc);
220 }
221 
222 static void idma64_vdesc_free(struct virt_dma_desc *vdesc)
223 {
224 	struct idma64_chan *idma64c = to_idma64_chan(vdesc->tx.chan);
225 
226 	idma64_desc_free(idma64c, to_idma64_desc(vdesc));
227 }
228 
229 static void idma64_hw_desc_fill(struct idma64_hw_desc *hw,
230 		struct dma_slave_config *config,
231 		enum dma_transfer_direction direction, u64 llp)
232 {
233 	struct idma64_lli *lli = hw->lli;
234 	u64 sar, dar;
235 	u32 ctlhi = IDMA64C_CTLH_BLOCK_TS(hw->len);
236 	u32 ctllo = IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN;
237 	u32 src_width, dst_width;
238 
239 	if (direction == DMA_MEM_TO_DEV) {
240 		sar = hw->phys;
241 		dar = config->dst_addr;
242 		ctllo |= IDMA64C_CTLL_DST_FIX | IDMA64C_CTLL_SRC_INC |
243 			 IDMA64C_CTLL_FC_M2P;
244 		src_width = __ffs(sar | hw->len | 4);
245 		dst_width = __ffs(config->dst_addr_width);
246 	} else {	/* DMA_DEV_TO_MEM */
247 		sar = config->src_addr;
248 		dar = hw->phys;
249 		ctllo |= IDMA64C_CTLL_DST_INC | IDMA64C_CTLL_SRC_FIX |
250 			 IDMA64C_CTLL_FC_P2M;
251 		src_width = __ffs(config->src_addr_width);
252 		dst_width = __ffs(dar | hw->len | 4);
253 	}
254 
255 	lli->sar = sar;
256 	lli->dar = dar;
257 
258 	lli->ctlhi = ctlhi;
259 	lli->ctllo = ctllo |
260 		     IDMA64C_CTLL_SRC_MSIZE(config->src_maxburst) |
261 		     IDMA64C_CTLL_DST_MSIZE(config->dst_maxburst) |
262 		     IDMA64C_CTLL_DST_WIDTH(dst_width) |
263 		     IDMA64C_CTLL_SRC_WIDTH(src_width);
264 
265 	lli->llp = llp;
266 }
267 
268 static void idma64_desc_fill(struct idma64_chan *idma64c,
269 		struct idma64_desc *desc)
270 {
271 	struct dma_slave_config *config = &idma64c->config;
272 	unsigned int i = desc->ndesc;
273 	struct idma64_hw_desc *hw = &desc->hw[i - 1];
274 	struct idma64_lli *lli = hw->lli;
275 	u64 llp = 0;
276 
277 	/* Fill the hardware descriptors and link them to a list */
278 	do {
279 		hw = &desc->hw[--i];
280 		idma64_hw_desc_fill(hw, config, desc->direction, llp);
281 		llp = hw->llp;
282 		desc->length += hw->len;
283 	} while (i);
284 
285 	/* Trigger an interrupt after the last block is transfered */
286 	lli->ctllo |= IDMA64C_CTLL_INT_EN;
287 
288 	/* Disable LLP transfer in the last block */
289 	lli->ctllo &= ~(IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN);
290 }
291 
292 static struct dma_async_tx_descriptor *idma64_prep_slave_sg(
293 		struct dma_chan *chan, struct scatterlist *sgl,
294 		unsigned int sg_len, enum dma_transfer_direction direction,
295 		unsigned long flags, void *context)
296 {
297 	struct idma64_chan *idma64c = to_idma64_chan(chan);
298 	struct idma64_desc *desc;
299 	struct scatterlist *sg;
300 	unsigned int i;
301 
302 	desc = idma64_alloc_desc(sg_len);
303 	if (!desc)
304 		return NULL;
305 
306 	for_each_sg(sgl, sg, sg_len, i) {
307 		struct idma64_hw_desc *hw = &desc->hw[i];
308 
309 		/* Allocate DMA capable memory for hardware descriptor */
310 		hw->lli = dma_pool_alloc(idma64c->pool, GFP_NOWAIT, &hw->llp);
311 		if (!hw->lli) {
312 			desc->ndesc = i;
313 			idma64_desc_free(idma64c, desc);
314 			return NULL;
315 		}
316 
317 		hw->phys = sg_dma_address(sg);
318 		hw->len = sg_dma_len(sg);
319 	}
320 
321 	desc->ndesc = sg_len;
322 	desc->direction = direction;
323 	desc->status = DMA_IN_PROGRESS;
324 
325 	idma64_desc_fill(idma64c, desc);
326 	return vchan_tx_prep(&idma64c->vchan, &desc->vdesc, flags);
327 }
328 
329 static void idma64_issue_pending(struct dma_chan *chan)
330 {
331 	struct idma64_chan *idma64c = to_idma64_chan(chan);
332 	unsigned long flags;
333 
334 	spin_lock_irqsave(&idma64c->vchan.lock, flags);
335 	if (vchan_issue_pending(&idma64c->vchan) && !idma64c->desc)
336 		idma64_start_transfer(idma64c);
337 	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
338 }
339 
340 static size_t idma64_active_desc_size(struct idma64_chan *idma64c)
341 {
342 	struct idma64_desc *desc = idma64c->desc;
343 	struct idma64_hw_desc *hw;
344 	size_t bytes = desc->length;
345 	u64 llp = channel_readq(idma64c, LLP);
346 	u32 ctlhi = channel_readl(idma64c, CTL_HI);
347 	unsigned int i = 0;
348 
349 	do {
350 		hw = &desc->hw[i];
351 		if (hw->llp == llp)
352 			break;
353 		bytes -= hw->len;
354 	} while (++i < desc->ndesc);
355 
356 	if (!i)
357 		return bytes;
358 
359 	/* The current chunk is not fully transfered yet */
360 	bytes += desc->hw[--i].len;
361 
362 	return bytes - IDMA64C_CTLH_BLOCK_TS(ctlhi);
363 }
364 
365 static enum dma_status idma64_tx_status(struct dma_chan *chan,
366 		dma_cookie_t cookie, struct dma_tx_state *state)
367 {
368 	struct idma64_chan *idma64c = to_idma64_chan(chan);
369 	struct virt_dma_desc *vdesc;
370 	enum dma_status status;
371 	size_t bytes;
372 	unsigned long flags;
373 
374 	status = dma_cookie_status(chan, cookie, state);
375 	if (status == DMA_COMPLETE)
376 		return status;
377 
378 	spin_lock_irqsave(&idma64c->vchan.lock, flags);
379 	vdesc = vchan_find_desc(&idma64c->vchan, cookie);
380 	if (idma64c->desc && cookie == idma64c->desc->vdesc.tx.cookie) {
381 		bytes = idma64_active_desc_size(idma64c);
382 		dma_set_residue(state, bytes);
383 		status = idma64c->desc->status;
384 	} else if (vdesc) {
385 		bytes = to_idma64_desc(vdesc)->length;
386 		dma_set_residue(state, bytes);
387 	}
388 	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
389 
390 	return status;
391 }
392 
393 static void convert_burst(u32 *maxburst)
394 {
395 	if (*maxburst)
396 		*maxburst = __fls(*maxburst);
397 	else
398 		*maxburst = 0;
399 }
400 
401 static int idma64_slave_config(struct dma_chan *chan,
402 		struct dma_slave_config *config)
403 {
404 	struct idma64_chan *idma64c = to_idma64_chan(chan);
405 
406 	memcpy(&idma64c->config, config, sizeof(idma64c->config));
407 
408 	convert_burst(&idma64c->config.src_maxburst);
409 	convert_burst(&idma64c->config.dst_maxburst);
410 
411 	return 0;
412 }
413 
414 static void idma64_chan_deactivate(struct idma64_chan *idma64c, bool drain)
415 {
416 	unsigned short count = 100;
417 	u32 cfglo;
418 
419 	cfglo = channel_readl(idma64c, CFG_LO);
420 	if (drain)
421 		cfglo |= IDMA64C_CFGL_CH_DRAIN;
422 	else
423 		cfglo &= ~IDMA64C_CFGL_CH_DRAIN;
424 
425 	channel_writel(idma64c, CFG_LO, cfglo | IDMA64C_CFGL_CH_SUSP);
426 	do {
427 		udelay(1);
428 		cfglo = channel_readl(idma64c, CFG_LO);
429 	} while (!(cfglo & IDMA64C_CFGL_FIFO_EMPTY) && --count);
430 }
431 
432 static void idma64_chan_activate(struct idma64_chan *idma64c)
433 {
434 	u32 cfglo;
435 
436 	cfglo = channel_readl(idma64c, CFG_LO);
437 	channel_writel(idma64c, CFG_LO, cfglo & ~IDMA64C_CFGL_CH_SUSP);
438 }
439 
440 static int idma64_pause(struct dma_chan *chan)
441 {
442 	struct idma64_chan *idma64c = to_idma64_chan(chan);
443 	unsigned long flags;
444 
445 	spin_lock_irqsave(&idma64c->vchan.lock, flags);
446 	if (idma64c->desc && idma64c->desc->status == DMA_IN_PROGRESS) {
447 		idma64_chan_deactivate(idma64c, false);
448 		idma64c->desc->status = DMA_PAUSED;
449 	}
450 	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
451 
452 	return 0;
453 }
454 
455 static int idma64_resume(struct dma_chan *chan)
456 {
457 	struct idma64_chan *idma64c = to_idma64_chan(chan);
458 	unsigned long flags;
459 
460 	spin_lock_irqsave(&idma64c->vchan.lock, flags);
461 	if (idma64c->desc && idma64c->desc->status == DMA_PAUSED) {
462 		idma64c->desc->status = DMA_IN_PROGRESS;
463 		idma64_chan_activate(idma64c);
464 	}
465 	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
466 
467 	return 0;
468 }
469 
470 static int idma64_terminate_all(struct dma_chan *chan)
471 {
472 	struct idma64_chan *idma64c = to_idma64_chan(chan);
473 	unsigned long flags;
474 	LIST_HEAD(head);
475 
476 	spin_lock_irqsave(&idma64c->vchan.lock, flags);
477 	idma64_chan_deactivate(idma64c, true);
478 	idma64_stop_transfer(idma64c);
479 	if (idma64c->desc) {
480 		idma64_vdesc_free(&idma64c->desc->vdesc);
481 		idma64c->desc = NULL;
482 	}
483 	vchan_get_all_descriptors(&idma64c->vchan, &head);
484 	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
485 
486 	vchan_dma_desc_free_list(&idma64c->vchan, &head);
487 	return 0;
488 }
489 
490 static void idma64_synchronize(struct dma_chan *chan)
491 {
492 	struct idma64_chan *idma64c = to_idma64_chan(chan);
493 
494 	vchan_synchronize(&idma64c->vchan);
495 }
496 
497 static int idma64_alloc_chan_resources(struct dma_chan *chan)
498 {
499 	struct idma64_chan *idma64c = to_idma64_chan(chan);
500 
501 	/* Create a pool of consistent memory blocks for hardware descriptors */
502 	idma64c->pool = dma_pool_create(dev_name(chan2dev(chan)),
503 					chan->device->dev,
504 					sizeof(struct idma64_lli), 8, 0);
505 	if (!idma64c->pool) {
506 		dev_err(chan2dev(chan), "No memory for descriptors\n");
507 		return -ENOMEM;
508 	}
509 
510 	return 0;
511 }
512 
513 static void idma64_free_chan_resources(struct dma_chan *chan)
514 {
515 	struct idma64_chan *idma64c = to_idma64_chan(chan);
516 
517 	vchan_free_chan_resources(to_virt_chan(chan));
518 	dma_pool_destroy(idma64c->pool);
519 	idma64c->pool = NULL;
520 }
521 
522 /* ---------------------------------------------------------------------- */
523 
524 #define IDMA64_BUSWIDTHS				\
525 	BIT(DMA_SLAVE_BUSWIDTH_1_BYTE)		|	\
526 	BIT(DMA_SLAVE_BUSWIDTH_2_BYTES)		|	\
527 	BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)
528 
529 static int idma64_probe(struct idma64_chip *chip)
530 {
531 	struct idma64 *idma64;
532 	unsigned short nr_chan = IDMA64_NR_CHAN;
533 	unsigned short i;
534 	int ret;
535 
536 	idma64 = devm_kzalloc(chip->dev, sizeof(*idma64), GFP_KERNEL);
537 	if (!idma64)
538 		return -ENOMEM;
539 
540 	idma64->regs = chip->regs;
541 	chip->idma64 = idma64;
542 
543 	idma64->chan = devm_kcalloc(chip->dev, nr_chan, sizeof(*idma64->chan),
544 				    GFP_KERNEL);
545 	if (!idma64->chan)
546 		return -ENOMEM;
547 
548 	idma64->all_chan_mask = (1 << nr_chan) - 1;
549 
550 	/* Turn off iDMA controller */
551 	idma64_off(idma64);
552 
553 	ret = devm_request_irq(chip->dev, chip->irq, idma64_irq, IRQF_SHARED,
554 			       dev_name(chip->dev), idma64);
555 	if (ret)
556 		return ret;
557 
558 	INIT_LIST_HEAD(&idma64->dma.channels);
559 	for (i = 0; i < nr_chan; i++) {
560 		struct idma64_chan *idma64c = &idma64->chan[i];
561 
562 		idma64c->vchan.desc_free = idma64_vdesc_free;
563 		vchan_init(&idma64c->vchan, &idma64->dma);
564 
565 		idma64c->regs = idma64->regs + i * IDMA64_CH_LENGTH;
566 		idma64c->mask = BIT(i);
567 	}
568 
569 	dma_cap_set(DMA_SLAVE, idma64->dma.cap_mask);
570 	dma_cap_set(DMA_PRIVATE, idma64->dma.cap_mask);
571 
572 	idma64->dma.device_alloc_chan_resources = idma64_alloc_chan_resources;
573 	idma64->dma.device_free_chan_resources = idma64_free_chan_resources;
574 
575 	idma64->dma.device_prep_slave_sg = idma64_prep_slave_sg;
576 
577 	idma64->dma.device_issue_pending = idma64_issue_pending;
578 	idma64->dma.device_tx_status = idma64_tx_status;
579 
580 	idma64->dma.device_config = idma64_slave_config;
581 	idma64->dma.device_pause = idma64_pause;
582 	idma64->dma.device_resume = idma64_resume;
583 	idma64->dma.device_terminate_all = idma64_terminate_all;
584 	idma64->dma.device_synchronize = idma64_synchronize;
585 
586 	idma64->dma.src_addr_widths = IDMA64_BUSWIDTHS;
587 	idma64->dma.dst_addr_widths = IDMA64_BUSWIDTHS;
588 	idma64->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
589 	idma64->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
590 
591 	idma64->dma.dev = chip->sysdev;
592 
593 	dma_set_max_seg_size(idma64->dma.dev, IDMA64C_CTLH_BLOCK_TS_MASK);
594 
595 	ret = dma_async_device_register(&idma64->dma);
596 	if (ret)
597 		return ret;
598 
599 	dev_info(chip->dev, "Found Intel integrated DMA 64-bit\n");
600 	return 0;
601 }
602 
603 static int idma64_remove(struct idma64_chip *chip)
604 {
605 	struct idma64 *idma64 = chip->idma64;
606 	unsigned short i;
607 
608 	dma_async_device_unregister(&idma64->dma);
609 
610 	/*
611 	 * Explicitly call devm_request_irq() to avoid the side effects with
612 	 * the scheduled tasklets.
613 	 */
614 	devm_free_irq(chip->dev, chip->irq, idma64);
615 
616 	for (i = 0; i < idma64->dma.chancnt; i++) {
617 		struct idma64_chan *idma64c = &idma64->chan[i];
618 
619 		tasklet_kill(&idma64c->vchan.task);
620 	}
621 
622 	return 0;
623 }
624 
625 /* ---------------------------------------------------------------------- */
626 
627 static int idma64_platform_probe(struct platform_device *pdev)
628 {
629 	struct idma64_chip *chip;
630 	struct device *dev = &pdev->dev;
631 	struct device *sysdev = dev->parent;
632 	struct resource *mem;
633 	int ret;
634 
635 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
636 	if (!chip)
637 		return -ENOMEM;
638 
639 	chip->irq = platform_get_irq(pdev, 0);
640 	if (chip->irq < 0)
641 		return chip->irq;
642 
643 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
644 	chip->regs = devm_ioremap_resource(dev, mem);
645 	if (IS_ERR(chip->regs))
646 		return PTR_ERR(chip->regs);
647 
648 	ret = dma_coerce_mask_and_coherent(sysdev, DMA_BIT_MASK(64));
649 	if (ret)
650 		return ret;
651 
652 	chip->dev = dev;
653 	chip->sysdev = sysdev;
654 
655 	ret = idma64_probe(chip);
656 	if (ret)
657 		return ret;
658 
659 	platform_set_drvdata(pdev, chip);
660 	return 0;
661 }
662 
663 static int idma64_platform_remove(struct platform_device *pdev)
664 {
665 	struct idma64_chip *chip = platform_get_drvdata(pdev);
666 
667 	return idma64_remove(chip);
668 }
669 
670 #ifdef CONFIG_PM_SLEEP
671 
672 static int idma64_pm_suspend(struct device *dev)
673 {
674 	struct idma64_chip *chip = dev_get_drvdata(dev);
675 
676 	idma64_off(chip->idma64);
677 	return 0;
678 }
679 
680 static int idma64_pm_resume(struct device *dev)
681 {
682 	struct idma64_chip *chip = dev_get_drvdata(dev);
683 
684 	idma64_on(chip->idma64);
685 	return 0;
686 }
687 
688 #endif /* CONFIG_PM_SLEEP */
689 
690 static const struct dev_pm_ops idma64_dev_pm_ops = {
691 	SET_SYSTEM_SLEEP_PM_OPS(idma64_pm_suspend, idma64_pm_resume)
692 };
693 
694 static struct platform_driver idma64_platform_driver = {
695 	.probe		= idma64_platform_probe,
696 	.remove		= idma64_platform_remove,
697 	.driver = {
698 		.name	= LPSS_IDMA64_DRIVER_NAME,
699 		.pm	= &idma64_dev_pm_ops,
700 	},
701 };
702 
703 module_platform_driver(idma64_platform_driver);
704 
705 MODULE_LICENSE("GPL v2");
706 MODULE_DESCRIPTION("iDMA64 core driver");
707 MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
708 MODULE_ALIAS("platform:" LPSS_IDMA64_DRIVER_NAME);
709