xref: /openbmc/linux/drivers/dma/fsl-edma-main.c (revision a34a9f1a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * drivers/dma/fsl-edma.c
4  *
5  * Copyright 2013-2014 Freescale Semiconductor, Inc.
6  *
7  * Driver for the Freescale eDMA engine with flexible channel multiplexing
8  * capability for DMA request sources. The eDMA block can be found on some
9  * Vybrid and Layerscape SoCs.
10  */
11 
12 #include <linux/module.h>
13 #include <linux/interrupt.h>
14 #include <linux/clk.h>
15 #include <linux/of.h>
16 #include <linux/of_device.h>
17 #include <linux/of_address.h>
18 #include <linux/of_irq.h>
19 #include <linux/of_dma.h>
20 #include <linux/dma-mapping.h>
21 #include <linux/pm_runtime.h>
22 #include <linux/pm_domain.h>
23 
24 #include "fsl-edma-common.h"
25 
26 #define ARGS_RX                         BIT(0)
27 #define ARGS_REMOTE                     BIT(1)
28 #define ARGS_MULTI_FIFO                 BIT(2)
29 
30 static void fsl_edma_synchronize(struct dma_chan *chan)
31 {
32 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
33 
34 	vchan_synchronize(&fsl_chan->vchan);
35 }
36 
37 static irqreturn_t fsl_edma_tx_handler(int irq, void *dev_id)
38 {
39 	struct fsl_edma_engine *fsl_edma = dev_id;
40 	unsigned int intr, ch;
41 	struct edma_regs *regs = &fsl_edma->regs;
42 
43 	intr = edma_readl(fsl_edma, regs->intl);
44 	if (!intr)
45 		return IRQ_NONE;
46 
47 	for (ch = 0; ch < fsl_edma->n_chans; ch++) {
48 		if (intr & (0x1 << ch)) {
49 			edma_writeb(fsl_edma, EDMA_CINT_CINT(ch), regs->cint);
50 			fsl_edma_tx_chan_handler(&fsl_edma->chans[ch]);
51 		}
52 	}
53 	return IRQ_HANDLED;
54 }
55 
56 static irqreturn_t fsl_edma3_tx_handler(int irq, void *dev_id)
57 {
58 	struct fsl_edma_chan *fsl_chan = dev_id;
59 	unsigned int intr;
60 
61 	intr = edma_readl_chreg(fsl_chan, ch_int);
62 	if (!intr)
63 		return IRQ_HANDLED;
64 
65 	edma_writel_chreg(fsl_chan, 1, ch_int);
66 
67 	fsl_edma_tx_chan_handler(fsl_chan);
68 
69 	return IRQ_HANDLED;
70 }
71 
72 static irqreturn_t fsl_edma_err_handler(int irq, void *dev_id)
73 {
74 	struct fsl_edma_engine *fsl_edma = dev_id;
75 	unsigned int err, ch;
76 	struct edma_regs *regs = &fsl_edma->regs;
77 
78 	err = edma_readl(fsl_edma, regs->errl);
79 	if (!err)
80 		return IRQ_NONE;
81 
82 	for (ch = 0; ch < fsl_edma->n_chans; ch++) {
83 		if (err & (0x1 << ch)) {
84 			fsl_edma_disable_request(&fsl_edma->chans[ch]);
85 			edma_writeb(fsl_edma, EDMA_CERR_CERR(ch), regs->cerr);
86 			fsl_edma_err_chan_handler(&fsl_edma->chans[ch]);
87 		}
88 	}
89 	return IRQ_HANDLED;
90 }
91 
92 static irqreturn_t fsl_edma_irq_handler(int irq, void *dev_id)
93 {
94 	if (fsl_edma_tx_handler(irq, dev_id) == IRQ_HANDLED)
95 		return IRQ_HANDLED;
96 
97 	return fsl_edma_err_handler(irq, dev_id);
98 }
99 
100 static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
101 		struct of_dma *ofdma)
102 {
103 	struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
104 	struct dma_chan *chan, *_chan;
105 	struct fsl_edma_chan *fsl_chan;
106 	u32 dmamux_nr = fsl_edma->drvdata->dmamuxs;
107 	unsigned long chans_per_mux = fsl_edma->n_chans / dmamux_nr;
108 
109 	if (dma_spec->args_count != 2)
110 		return NULL;
111 
112 	mutex_lock(&fsl_edma->fsl_edma_mutex);
113 	list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels, device_node) {
114 		if (chan->client_count)
115 			continue;
116 		if ((chan->chan_id / chans_per_mux) == dma_spec->args[0]) {
117 			chan = dma_get_slave_channel(chan);
118 			if (chan) {
119 				chan->device->privatecnt++;
120 				fsl_chan = to_fsl_edma_chan(chan);
121 				fsl_chan->slave_id = dma_spec->args[1];
122 				fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id,
123 						true);
124 				mutex_unlock(&fsl_edma->fsl_edma_mutex);
125 				return chan;
126 			}
127 		}
128 	}
129 	mutex_unlock(&fsl_edma->fsl_edma_mutex);
130 	return NULL;
131 }
132 
133 static struct dma_chan *fsl_edma3_xlate(struct of_phandle_args *dma_spec,
134 					struct of_dma *ofdma)
135 {
136 	struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
137 	struct dma_chan *chan, *_chan;
138 	struct fsl_edma_chan *fsl_chan;
139 	bool b_chmux;
140 	int i;
141 
142 	if (dma_spec->args_count != 3)
143 		return NULL;
144 
145 	b_chmux = !!(fsl_edma->drvdata->flags & FSL_EDMA_DRV_HAS_CHMUX);
146 
147 	mutex_lock(&fsl_edma->fsl_edma_mutex);
148 	list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels,
149 					device_node) {
150 
151 		if (chan->client_count)
152 			continue;
153 
154 		fsl_chan = to_fsl_edma_chan(chan);
155 		i = fsl_chan - fsl_edma->chans;
156 
157 		chan = dma_get_slave_channel(chan);
158 		chan->device->privatecnt++;
159 		fsl_chan->priority = dma_spec->args[1];
160 		fsl_chan->is_rxchan = dma_spec->args[2] & ARGS_RX;
161 		fsl_chan->is_remote = dma_spec->args[2] & ARGS_REMOTE;
162 		fsl_chan->is_multi_fifo = dma_spec->args[2] & ARGS_MULTI_FIFO;
163 
164 		if (!b_chmux && i == dma_spec->args[0]) {
165 			mutex_unlock(&fsl_edma->fsl_edma_mutex);
166 			return chan;
167 		} else if (b_chmux && !fsl_chan->srcid) {
168 			/* if controller support channel mux, choose a free channel */
169 			fsl_chan->srcid = dma_spec->args[0];
170 			mutex_unlock(&fsl_edma->fsl_edma_mutex);
171 			return chan;
172 		}
173 	}
174 	mutex_unlock(&fsl_edma->fsl_edma_mutex);
175 	return NULL;
176 }
177 
178 static int
179 fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
180 {
181 	int ret;
182 
183 	edma_writel(fsl_edma, ~0, fsl_edma->regs.intl);
184 
185 	fsl_edma->txirq = platform_get_irq_byname(pdev, "edma-tx");
186 	if (fsl_edma->txirq < 0)
187 		return fsl_edma->txirq;
188 
189 	fsl_edma->errirq = platform_get_irq_byname(pdev, "edma-err");
190 	if (fsl_edma->errirq < 0)
191 		return fsl_edma->errirq;
192 
193 	if (fsl_edma->txirq == fsl_edma->errirq) {
194 		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
195 				fsl_edma_irq_handler, 0, "eDMA", fsl_edma);
196 		if (ret) {
197 			dev_err(&pdev->dev, "Can't register eDMA IRQ.\n");
198 			return ret;
199 		}
200 	} else {
201 		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
202 				fsl_edma_tx_handler, 0, "eDMA tx", fsl_edma);
203 		if (ret) {
204 			dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n");
205 			return ret;
206 		}
207 
208 		ret = devm_request_irq(&pdev->dev, fsl_edma->errirq,
209 				fsl_edma_err_handler, 0, "eDMA err", fsl_edma);
210 		if (ret) {
211 			dev_err(&pdev->dev, "Can't register eDMA err IRQ.\n");
212 			return ret;
213 		}
214 	}
215 
216 	return 0;
217 }
218 
219 static int fsl_edma3_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
220 {
221 	int ret;
222 	int i;
223 
224 	for (i = 0; i < fsl_edma->n_chans; i++) {
225 
226 		struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];
227 
228 		if (fsl_edma->chan_masked & BIT(i))
229 			continue;
230 
231 		/* request channel irq */
232 		fsl_chan->txirq = platform_get_irq(pdev, i);
233 		if (fsl_chan->txirq < 0) {
234 			dev_err(&pdev->dev, "Can't get chan %d's irq.\n", i);
235 			return  -EINVAL;
236 		}
237 
238 		ret = devm_request_irq(&pdev->dev, fsl_chan->txirq,
239 			fsl_edma3_tx_handler, IRQF_SHARED,
240 			fsl_chan->chan_name, fsl_chan);
241 		if (ret) {
242 			dev_err(&pdev->dev, "Can't register chan%d's IRQ.\n", i);
243 			return -EINVAL;
244 		}
245 	}
246 
247 	return 0;
248 }
249 
250 static int
251 fsl_edma2_irq_init(struct platform_device *pdev,
252 		   struct fsl_edma_engine *fsl_edma)
253 {
254 	int i, ret, irq;
255 	int count;
256 
257 	edma_writel(fsl_edma, ~0, fsl_edma->regs.intl);
258 
259 	count = platform_irq_count(pdev);
260 	dev_dbg(&pdev->dev, "%s Found %d interrupts\r\n", __func__, count);
261 	if (count <= 2) {
262 		dev_err(&pdev->dev, "Interrupts in DTS not correct.\n");
263 		return -EINVAL;
264 	}
265 	/*
266 	 * 16 channel independent interrupts + 1 error interrupt on i.mx7ulp.
267 	 * 2 channel share one interrupt, for example, ch0/ch16, ch1/ch17...
268 	 * For now, just simply request irq without IRQF_SHARED flag, since 16
269 	 * channels are enough on i.mx7ulp whose M4 domain own some peripherals.
270 	 */
271 	for (i = 0; i < count; i++) {
272 		irq = platform_get_irq(pdev, i);
273 		if (irq < 0)
274 			return -ENXIO;
275 
276 		/* The last IRQ is for eDMA err */
277 		if (i == count - 1)
278 			ret = devm_request_irq(&pdev->dev, irq,
279 						fsl_edma_err_handler,
280 						0, "eDMA2-ERR", fsl_edma);
281 		else
282 			ret = devm_request_irq(&pdev->dev, irq,
283 						fsl_edma_tx_handler, 0,
284 						fsl_edma->chans[i].chan_name,
285 						fsl_edma);
286 		if (ret)
287 			return ret;
288 	}
289 
290 	return 0;
291 }
292 
293 static void fsl_edma_irq_exit(
294 		struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
295 {
296 	if (fsl_edma->txirq == fsl_edma->errirq) {
297 		devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
298 	} else {
299 		devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
300 		devm_free_irq(&pdev->dev, fsl_edma->errirq, fsl_edma);
301 	}
302 }
303 
304 static void fsl_disable_clocks(struct fsl_edma_engine *fsl_edma, int nr_clocks)
305 {
306 	int i;
307 
308 	for (i = 0; i < nr_clocks; i++)
309 		clk_disable_unprepare(fsl_edma->muxclk[i]);
310 }
311 
312 static struct fsl_edma_drvdata vf610_data = {
313 	.dmamuxs = DMAMUX_NR,
314 	.flags = FSL_EDMA_DRV_WRAP_IO,
315 	.chreg_off = EDMA_TCD,
316 	.chreg_space_sz = sizeof(struct fsl_edma_hw_tcd),
317 	.setup_irq = fsl_edma_irq_init,
318 };
319 
320 static struct fsl_edma_drvdata ls1028a_data = {
321 	.dmamuxs = DMAMUX_NR,
322 	.flags = FSL_EDMA_DRV_MUX_SWAP | FSL_EDMA_DRV_WRAP_IO,
323 	.chreg_off = EDMA_TCD,
324 	.chreg_space_sz = sizeof(struct fsl_edma_hw_tcd),
325 	.setup_irq = fsl_edma_irq_init,
326 };
327 
328 static struct fsl_edma_drvdata imx7ulp_data = {
329 	.dmamuxs = 1,
330 	.chreg_off = EDMA_TCD,
331 	.chreg_space_sz = sizeof(struct fsl_edma_hw_tcd),
332 	.flags = FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_CONFIG32,
333 	.setup_irq = fsl_edma2_irq_init,
334 };
335 
336 static struct fsl_edma_drvdata imx8qm_data = {
337 	.flags = FSL_EDMA_DRV_HAS_PD | FSL_EDMA_DRV_EDMA3,
338 	.chreg_space_sz = 0x10000,
339 	.chreg_off = 0x10000,
340 	.setup_irq = fsl_edma3_irq_init,
341 };
342 
343 static struct fsl_edma_drvdata imx8qm_audio_data = {
344 	.flags = FSL_EDMA_DRV_QUIRK_SWAPPED | FSL_EDMA_DRV_HAS_PD | FSL_EDMA_DRV_EDMA3,
345 	.chreg_space_sz = 0x10000,
346 	.chreg_off = 0x10000,
347 	.setup_irq = fsl_edma3_irq_init,
348 };
349 
350 static struct fsl_edma_drvdata imx93_data3 = {
351 	.flags = FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_EDMA3,
352 	.chreg_space_sz = 0x10000,
353 	.chreg_off = 0x10000,
354 	.setup_irq = fsl_edma3_irq_init,
355 };
356 
357 static struct fsl_edma_drvdata imx93_data4 = {
358 	.flags = FSL_EDMA_DRV_HAS_CHMUX | FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_EDMA3,
359 	.chreg_space_sz = 0x8000,
360 	.chreg_off = 0x10000,
361 	.setup_irq = fsl_edma3_irq_init,
362 };
363 
364 static const struct of_device_id fsl_edma_dt_ids[] = {
365 	{ .compatible = "fsl,vf610-edma", .data = &vf610_data},
366 	{ .compatible = "fsl,ls1028a-edma", .data = &ls1028a_data},
367 	{ .compatible = "fsl,imx7ulp-edma", .data = &imx7ulp_data},
368 	{ .compatible = "fsl,imx8qm-edma", .data = &imx8qm_data},
369 	{ .compatible = "fsl,imx8qm-adma", .data = &imx8qm_audio_data},
370 	{ .compatible = "fsl,imx93-edma3", .data = &imx93_data3},
371 	{ .compatible = "fsl,imx93-edma4", .data = &imx93_data4},
372 	{ /* sentinel */ }
373 };
374 MODULE_DEVICE_TABLE(of, fsl_edma_dt_ids);
375 
376 static int fsl_edma3_attach_pd(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
377 {
378 	struct fsl_edma_chan *fsl_chan;
379 	struct device_link *link;
380 	struct device *pd_chan;
381 	struct device *dev;
382 	int i;
383 
384 	dev = &pdev->dev;
385 
386 	for (i = 0; i < fsl_edma->n_chans; i++) {
387 		if (fsl_edma->chan_masked & BIT(i))
388 			continue;
389 
390 		fsl_chan = &fsl_edma->chans[i];
391 
392 		pd_chan = dev_pm_domain_attach_by_id(dev, i);
393 		if (IS_ERR_OR_NULL(pd_chan)) {
394 			dev_err(dev, "Failed attach pd %d\n", i);
395 			return -EINVAL;
396 		}
397 
398 		link = device_link_add(dev, pd_chan, DL_FLAG_STATELESS |
399 					     DL_FLAG_PM_RUNTIME |
400 					     DL_FLAG_RPM_ACTIVE);
401 		if (IS_ERR(link)) {
402 			dev_err(dev, "Failed to add device_link to %d: %ld\n", i,
403 				PTR_ERR(link));
404 			return -EINVAL;
405 		}
406 
407 		fsl_chan->pd_dev = pd_chan;
408 
409 		pm_runtime_use_autosuspend(fsl_chan->pd_dev);
410 		pm_runtime_set_autosuspend_delay(fsl_chan->pd_dev, 200);
411 		pm_runtime_set_active(fsl_chan->pd_dev);
412 	}
413 
414 	return 0;
415 }
416 
417 static int fsl_edma_probe(struct platform_device *pdev)
418 {
419 	const struct of_device_id *of_id =
420 			of_match_device(fsl_edma_dt_ids, &pdev->dev);
421 	struct device_node *np = pdev->dev.of_node;
422 	struct fsl_edma_engine *fsl_edma;
423 	const struct fsl_edma_drvdata *drvdata = NULL;
424 	u32 chan_mask[2] = {0, 0};
425 	struct edma_regs *regs;
426 	int chans;
427 	int ret, i;
428 
429 	if (of_id)
430 		drvdata = of_id->data;
431 	if (!drvdata) {
432 		dev_err(&pdev->dev, "unable to find driver data\n");
433 		return -EINVAL;
434 	}
435 
436 	ret = of_property_read_u32(np, "dma-channels", &chans);
437 	if (ret) {
438 		dev_err(&pdev->dev, "Can't get dma-channels.\n");
439 		return ret;
440 	}
441 
442 	fsl_edma = devm_kzalloc(&pdev->dev, struct_size(fsl_edma, chans, chans),
443 				GFP_KERNEL);
444 	if (!fsl_edma)
445 		return -ENOMEM;
446 
447 	fsl_edma->drvdata = drvdata;
448 	fsl_edma->n_chans = chans;
449 	mutex_init(&fsl_edma->fsl_edma_mutex);
450 
451 	fsl_edma->membase = devm_platform_ioremap_resource(pdev, 0);
452 	if (IS_ERR(fsl_edma->membase))
453 		return PTR_ERR(fsl_edma->membase);
454 
455 	if (!(drvdata->flags & FSL_EDMA_DRV_SPLIT_REG)) {
456 		fsl_edma_setup_regs(fsl_edma);
457 		regs = &fsl_edma->regs;
458 	}
459 
460 	if (drvdata->flags & FSL_EDMA_DRV_HAS_DMACLK) {
461 		fsl_edma->dmaclk = devm_clk_get_enabled(&pdev->dev, "dma");
462 		if (IS_ERR(fsl_edma->dmaclk)) {
463 			dev_err(&pdev->dev, "Missing DMA block clock.\n");
464 			return PTR_ERR(fsl_edma->dmaclk);
465 		}
466 	}
467 
468 	if (drvdata->flags & FSL_EDMA_DRV_HAS_CHCLK) {
469 		fsl_edma->chclk = devm_clk_get_enabled(&pdev->dev, "mp");
470 		if (IS_ERR(fsl_edma->chclk)) {
471 			dev_err(&pdev->dev, "Missing MP block clock.\n");
472 			return PTR_ERR(fsl_edma->chclk);
473 		}
474 	}
475 
476 	ret = of_property_read_variable_u32_array(np, "dma-channel-mask", chan_mask, 1, 2);
477 
478 	if (ret > 0) {
479 		fsl_edma->chan_masked = chan_mask[1];
480 		fsl_edma->chan_masked <<= 32;
481 		fsl_edma->chan_masked |= chan_mask[0];
482 	}
483 
484 	for (i = 0; i < fsl_edma->drvdata->dmamuxs; i++) {
485 		char clkname[32];
486 
487 		/* eDMAv3 mux register move to TCD area if ch_mux exist */
488 		if (drvdata->flags & FSL_EDMA_DRV_SPLIT_REG)
489 			break;
490 
491 		fsl_edma->muxbase[i] = devm_platform_ioremap_resource(pdev,
492 								      1 + i);
493 		if (IS_ERR(fsl_edma->muxbase[i])) {
494 			/* on error: disable all previously enabled clks */
495 			fsl_disable_clocks(fsl_edma, i);
496 			return PTR_ERR(fsl_edma->muxbase[i]);
497 		}
498 
499 		sprintf(clkname, "dmamux%d", i);
500 		fsl_edma->muxclk[i] = devm_clk_get_enabled(&pdev->dev, clkname);
501 		if (IS_ERR(fsl_edma->muxclk[i])) {
502 			dev_err(&pdev->dev, "Missing DMAMUX block clock.\n");
503 			/* on error: disable all previously enabled clks */
504 			return PTR_ERR(fsl_edma->muxclk[i]);
505 		}
506 	}
507 
508 	fsl_edma->big_endian = of_property_read_bool(np, "big-endian");
509 
510 	if (drvdata->flags & FSL_EDMA_DRV_HAS_PD) {
511 		ret = fsl_edma3_attach_pd(pdev, fsl_edma);
512 		if (ret)
513 			return ret;
514 	}
515 
516 	INIT_LIST_HEAD(&fsl_edma->dma_dev.channels);
517 	for (i = 0; i < fsl_edma->n_chans; i++) {
518 		struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];
519 		int len;
520 
521 		if (fsl_edma->chan_masked & BIT(i))
522 			continue;
523 
524 		snprintf(fsl_chan->chan_name, sizeof(fsl_chan->chan_name), "%s-CH%02d",
525 							   dev_name(&pdev->dev), i);
526 
527 		fsl_chan->edma = fsl_edma;
528 		fsl_chan->pm_state = RUNNING;
529 		fsl_chan->slave_id = 0;
530 		fsl_chan->idle = true;
531 		fsl_chan->dma_dir = DMA_NONE;
532 		fsl_chan->vchan.desc_free = fsl_edma_free_desc;
533 
534 		len = (drvdata->flags & FSL_EDMA_DRV_SPLIT_REG) ?
535 				offsetof(struct fsl_edma3_ch_reg, tcd) : 0;
536 		fsl_chan->tcd = fsl_edma->membase
537 				+ i * drvdata->chreg_space_sz + drvdata->chreg_off + len;
538 
539 		fsl_chan->pdev = pdev;
540 		vchan_init(&fsl_chan->vchan, &fsl_edma->dma_dev);
541 
542 		edma_write_tcdreg(fsl_chan, 0, csr);
543 		fsl_edma_chan_mux(fsl_chan, 0, false);
544 	}
545 
546 	ret = fsl_edma->drvdata->setup_irq(pdev, fsl_edma);
547 	if (ret)
548 		return ret;
549 
550 	dma_cap_set(DMA_PRIVATE, fsl_edma->dma_dev.cap_mask);
551 	dma_cap_set(DMA_SLAVE, fsl_edma->dma_dev.cap_mask);
552 	dma_cap_set(DMA_CYCLIC, fsl_edma->dma_dev.cap_mask);
553 	dma_cap_set(DMA_MEMCPY, fsl_edma->dma_dev.cap_mask);
554 
555 	fsl_edma->dma_dev.dev = &pdev->dev;
556 	fsl_edma->dma_dev.device_alloc_chan_resources
557 		= fsl_edma_alloc_chan_resources;
558 	fsl_edma->dma_dev.device_free_chan_resources
559 		= fsl_edma_free_chan_resources;
560 	fsl_edma->dma_dev.device_tx_status = fsl_edma_tx_status;
561 	fsl_edma->dma_dev.device_prep_slave_sg = fsl_edma_prep_slave_sg;
562 	fsl_edma->dma_dev.device_prep_dma_cyclic = fsl_edma_prep_dma_cyclic;
563 	fsl_edma->dma_dev.device_prep_dma_memcpy = fsl_edma_prep_memcpy;
564 	fsl_edma->dma_dev.device_config = fsl_edma_slave_config;
565 	fsl_edma->dma_dev.device_pause = fsl_edma_pause;
566 	fsl_edma->dma_dev.device_resume = fsl_edma_resume;
567 	fsl_edma->dma_dev.device_terminate_all = fsl_edma_terminate_all;
568 	fsl_edma->dma_dev.device_synchronize = fsl_edma_synchronize;
569 	fsl_edma->dma_dev.device_issue_pending = fsl_edma_issue_pending;
570 
571 	fsl_edma->dma_dev.src_addr_widths = FSL_EDMA_BUSWIDTHS;
572 	fsl_edma->dma_dev.dst_addr_widths = FSL_EDMA_BUSWIDTHS;
573 
574 	if (drvdata->flags & FSL_EDMA_DRV_BUS_8BYTE) {
575 		fsl_edma->dma_dev.src_addr_widths |= BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
576 		fsl_edma->dma_dev.dst_addr_widths |= BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
577 	}
578 
579 	fsl_edma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
580 	if (drvdata->flags & FSL_EDMA_DRV_DEV_TO_DEV)
581 		fsl_edma->dma_dev.directions |= BIT(DMA_DEV_TO_DEV);
582 
583 	fsl_edma->dma_dev.copy_align = drvdata->flags & FSL_EDMA_DRV_ALIGN_64BYTE ?
584 					DMAENGINE_ALIGN_64_BYTES :
585 					DMAENGINE_ALIGN_32_BYTES;
586 
587 	/* Per worst case 'nbytes = 1' take CITER as the max_seg_size */
588 	dma_set_max_seg_size(fsl_edma->dma_dev.dev, 0x3fff);
589 
590 	fsl_edma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
591 
592 	platform_set_drvdata(pdev, fsl_edma);
593 
594 	ret = dma_async_device_register(&fsl_edma->dma_dev);
595 	if (ret) {
596 		dev_err(&pdev->dev,
597 			"Can't register Freescale eDMA engine. (%d)\n", ret);
598 		return ret;
599 	}
600 
601 	ret = of_dma_controller_register(np,
602 			drvdata->flags & FSL_EDMA_DRV_SPLIT_REG ? fsl_edma3_xlate : fsl_edma_xlate,
603 			fsl_edma);
604 	if (ret) {
605 		dev_err(&pdev->dev,
606 			"Can't register Freescale eDMA of_dma. (%d)\n", ret);
607 		dma_async_device_unregister(&fsl_edma->dma_dev);
608 		return ret;
609 	}
610 
611 	/* enable round robin arbitration */
612 	if (!(drvdata->flags & FSL_EDMA_DRV_SPLIT_REG))
613 		edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
614 
615 	return 0;
616 }
617 
618 static int fsl_edma_remove(struct platform_device *pdev)
619 {
620 	struct device_node *np = pdev->dev.of_node;
621 	struct fsl_edma_engine *fsl_edma = platform_get_drvdata(pdev);
622 
623 	fsl_edma_irq_exit(pdev, fsl_edma);
624 	fsl_edma_cleanup_vchan(&fsl_edma->dma_dev);
625 	of_dma_controller_free(np);
626 	dma_async_device_unregister(&fsl_edma->dma_dev);
627 	fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs);
628 
629 	return 0;
630 }
631 
632 static int fsl_edma_suspend_late(struct device *dev)
633 {
634 	struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
635 	struct fsl_edma_chan *fsl_chan;
636 	unsigned long flags;
637 	int i;
638 
639 	for (i = 0; i < fsl_edma->n_chans; i++) {
640 		fsl_chan = &fsl_edma->chans[i];
641 		spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
642 		/* Make sure chan is idle or will force disable. */
643 		if (unlikely(!fsl_chan->idle)) {
644 			dev_warn(dev, "WARN: There is non-idle channel.");
645 			fsl_edma_disable_request(fsl_chan);
646 			fsl_edma_chan_mux(fsl_chan, 0, false);
647 		}
648 
649 		fsl_chan->pm_state = SUSPENDED;
650 		spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
651 	}
652 
653 	return 0;
654 }
655 
656 static int fsl_edma_resume_early(struct device *dev)
657 {
658 	struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
659 	struct fsl_edma_chan *fsl_chan;
660 	struct edma_regs *regs = &fsl_edma->regs;
661 	int i;
662 
663 	for (i = 0; i < fsl_edma->n_chans; i++) {
664 		fsl_chan = &fsl_edma->chans[i];
665 		fsl_chan->pm_state = RUNNING;
666 		edma_write_tcdreg(fsl_chan, 0, csr);
667 		if (fsl_chan->slave_id != 0)
668 			fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id, true);
669 	}
670 
671 	edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
672 
673 	return 0;
674 }
675 
676 /*
677  * eDMA provides the service to others, so it should be suspend late
678  * and resume early. When eDMA suspend, all of the clients should stop
679  * the DMA data transmission and let the channel idle.
680  */
681 static const struct dev_pm_ops fsl_edma_pm_ops = {
682 	.suspend_late   = fsl_edma_suspend_late,
683 	.resume_early   = fsl_edma_resume_early,
684 };
685 
686 static struct platform_driver fsl_edma_driver = {
687 	.driver		= {
688 		.name	= "fsl-edma",
689 		.of_match_table = fsl_edma_dt_ids,
690 		.pm     = &fsl_edma_pm_ops,
691 	},
692 	.probe          = fsl_edma_probe,
693 	.remove		= fsl_edma_remove,
694 };
695 
696 static int __init fsl_edma_init(void)
697 {
698 	return platform_driver_register(&fsl_edma_driver);
699 }
700 subsys_initcall(fsl_edma_init);
701 
702 static void __exit fsl_edma_exit(void)
703 {
704 	platform_driver_unregister(&fsl_edma_driver);
705 }
706 module_exit(fsl_edma_exit);
707 
708 MODULE_ALIAS("platform:fsl-edma");
709 MODULE_DESCRIPTION("Freescale eDMA engine driver");
710 MODULE_LICENSE("GPL v2");
711