xref: /openbmc/linux/drivers/dma/fsl-edma-main.c (revision 3ddc8b84)
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 		fsl_chan->priority = dma_spec->args[1];
158 		fsl_chan->is_rxchan = dma_spec->args[2] & ARGS_RX;
159 		fsl_chan->is_remote = dma_spec->args[2] & ARGS_REMOTE;
160 		fsl_chan->is_multi_fifo = dma_spec->args[2] & ARGS_MULTI_FIFO;
161 
162 		if (!b_chmux && i == dma_spec->args[0]) {
163 			chan = dma_get_slave_channel(chan);
164 			chan->device->privatecnt++;
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 			chan = dma_get_slave_channel(chan);
170 			chan->device->privatecnt++;
171 			fsl_chan->srcid = dma_spec->args[0];
172 			mutex_unlock(&fsl_edma->fsl_edma_mutex);
173 			return chan;
174 		}
175 	}
176 	mutex_unlock(&fsl_edma->fsl_edma_mutex);
177 	return NULL;
178 }
179 
180 static int
181 fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
182 {
183 	int ret;
184 
185 	edma_writel(fsl_edma, ~0, fsl_edma->regs.intl);
186 
187 	fsl_edma->txirq = platform_get_irq_byname(pdev, "edma-tx");
188 	if (fsl_edma->txirq < 0)
189 		return fsl_edma->txirq;
190 
191 	fsl_edma->errirq = platform_get_irq_byname(pdev, "edma-err");
192 	if (fsl_edma->errirq < 0)
193 		return fsl_edma->errirq;
194 
195 	if (fsl_edma->txirq == fsl_edma->errirq) {
196 		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
197 				fsl_edma_irq_handler, 0, "eDMA", fsl_edma);
198 		if (ret) {
199 			dev_err(&pdev->dev, "Can't register eDMA IRQ.\n");
200 			return ret;
201 		}
202 	} else {
203 		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
204 				fsl_edma_tx_handler, 0, "eDMA tx", fsl_edma);
205 		if (ret) {
206 			dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n");
207 			return ret;
208 		}
209 
210 		ret = devm_request_irq(&pdev->dev, fsl_edma->errirq,
211 				fsl_edma_err_handler, 0, "eDMA err", fsl_edma);
212 		if (ret) {
213 			dev_err(&pdev->dev, "Can't register eDMA err IRQ.\n");
214 			return ret;
215 		}
216 	}
217 
218 	return 0;
219 }
220 
221 static int fsl_edma3_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
222 {
223 	int ret;
224 	int i;
225 
226 	for (i = 0; i < fsl_edma->n_chans; i++) {
227 
228 		struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];
229 
230 		if (fsl_edma->chan_masked & BIT(i))
231 			continue;
232 
233 		/* request channel irq */
234 		fsl_chan->txirq = platform_get_irq(pdev, i);
235 		if (fsl_chan->txirq < 0) {
236 			dev_err(&pdev->dev, "Can't get chan %d's irq.\n", i);
237 			return  -EINVAL;
238 		}
239 
240 		ret = devm_request_irq(&pdev->dev, fsl_chan->txirq,
241 			fsl_edma3_tx_handler, IRQF_SHARED,
242 			fsl_chan->chan_name, fsl_chan);
243 		if (ret) {
244 			dev_err(&pdev->dev, "Can't register chan%d's IRQ.\n", i);
245 			return -EINVAL;
246 		}
247 	}
248 
249 	return 0;
250 }
251 
252 static int
253 fsl_edma2_irq_init(struct platform_device *pdev,
254 		   struct fsl_edma_engine *fsl_edma)
255 {
256 	int i, ret, irq;
257 	int count;
258 
259 	edma_writel(fsl_edma, ~0, fsl_edma->regs.intl);
260 
261 	count = platform_irq_count(pdev);
262 	dev_dbg(&pdev->dev, "%s Found %d interrupts\r\n", __func__, count);
263 	if (count <= 2) {
264 		dev_err(&pdev->dev, "Interrupts in DTS not correct.\n");
265 		return -EINVAL;
266 	}
267 	/*
268 	 * 16 channel independent interrupts + 1 error interrupt on i.mx7ulp.
269 	 * 2 channel share one interrupt, for example, ch0/ch16, ch1/ch17...
270 	 * For now, just simply request irq without IRQF_SHARED flag, since 16
271 	 * channels are enough on i.mx7ulp whose M4 domain own some peripherals.
272 	 */
273 	for (i = 0; i < count; i++) {
274 		irq = platform_get_irq(pdev, i);
275 		if (irq < 0)
276 			return -ENXIO;
277 
278 		/* The last IRQ is for eDMA err */
279 		if (i == count - 1)
280 			ret = devm_request_irq(&pdev->dev, irq,
281 						fsl_edma_err_handler,
282 						0, "eDMA2-ERR", fsl_edma);
283 		else
284 			ret = devm_request_irq(&pdev->dev, irq,
285 						fsl_edma_tx_handler, 0,
286 						fsl_edma->chans[i].chan_name,
287 						fsl_edma);
288 		if (ret)
289 			return ret;
290 	}
291 
292 	return 0;
293 }
294 
295 static void fsl_edma_irq_exit(
296 		struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
297 {
298 	if (fsl_edma->txirq == fsl_edma->errirq) {
299 		devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
300 	} else {
301 		devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
302 		devm_free_irq(&pdev->dev, fsl_edma->errirq, fsl_edma);
303 	}
304 }
305 
306 static void fsl_disable_clocks(struct fsl_edma_engine *fsl_edma, int nr_clocks)
307 {
308 	int i;
309 
310 	for (i = 0; i < nr_clocks; i++)
311 		clk_disable_unprepare(fsl_edma->muxclk[i]);
312 }
313 
314 static struct fsl_edma_drvdata vf610_data = {
315 	.dmamuxs = DMAMUX_NR,
316 	.flags = FSL_EDMA_DRV_WRAP_IO,
317 	.chreg_off = EDMA_TCD,
318 	.chreg_space_sz = sizeof(struct fsl_edma_hw_tcd),
319 	.setup_irq = fsl_edma_irq_init,
320 };
321 
322 static struct fsl_edma_drvdata ls1028a_data = {
323 	.dmamuxs = DMAMUX_NR,
324 	.flags = FSL_EDMA_DRV_MUX_SWAP | FSL_EDMA_DRV_WRAP_IO,
325 	.chreg_off = EDMA_TCD,
326 	.chreg_space_sz = sizeof(struct fsl_edma_hw_tcd),
327 	.setup_irq = fsl_edma_irq_init,
328 };
329 
330 static struct fsl_edma_drvdata imx7ulp_data = {
331 	.dmamuxs = 1,
332 	.chreg_off = EDMA_TCD,
333 	.chreg_space_sz = sizeof(struct fsl_edma_hw_tcd),
334 	.flags = FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_CONFIG32,
335 	.setup_irq = fsl_edma2_irq_init,
336 };
337 
338 static struct fsl_edma_drvdata imx8qm_data = {
339 	.flags = FSL_EDMA_DRV_HAS_PD | FSL_EDMA_DRV_EDMA3,
340 	.chreg_space_sz = 0x10000,
341 	.chreg_off = 0x10000,
342 	.setup_irq = fsl_edma3_irq_init,
343 };
344 
345 static struct fsl_edma_drvdata imx8qm_audio_data = {
346 	.flags = FSL_EDMA_DRV_QUIRK_SWAPPED | FSL_EDMA_DRV_HAS_PD | FSL_EDMA_DRV_EDMA3,
347 	.chreg_space_sz = 0x10000,
348 	.chreg_off = 0x10000,
349 	.setup_irq = fsl_edma3_irq_init,
350 };
351 
352 static struct fsl_edma_drvdata imx93_data3 = {
353 	.flags = FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_EDMA3,
354 	.chreg_space_sz = 0x10000,
355 	.chreg_off = 0x10000,
356 	.setup_irq = fsl_edma3_irq_init,
357 };
358 
359 static struct fsl_edma_drvdata imx93_data4 = {
360 	.flags = FSL_EDMA_DRV_HAS_CHMUX | FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_EDMA4,
361 	.chreg_space_sz = 0x8000,
362 	.chreg_off = 0x10000,
363 	.setup_irq = fsl_edma3_irq_init,
364 };
365 
366 static const struct of_device_id fsl_edma_dt_ids[] = {
367 	{ .compatible = "fsl,vf610-edma", .data = &vf610_data},
368 	{ .compatible = "fsl,ls1028a-edma", .data = &ls1028a_data},
369 	{ .compatible = "fsl,imx7ulp-edma", .data = &imx7ulp_data},
370 	{ .compatible = "fsl,imx8qm-edma", .data = &imx8qm_data},
371 	{ .compatible = "fsl,imx8qm-adma", .data = &imx8qm_audio_data},
372 	{ .compatible = "fsl,imx93-edma3", .data = &imx93_data3},
373 	{ .compatible = "fsl,imx93-edma4", .data = &imx93_data4},
374 	{ /* sentinel */ }
375 };
376 MODULE_DEVICE_TABLE(of, fsl_edma_dt_ids);
377 
378 static int fsl_edma3_attach_pd(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
379 {
380 	struct fsl_edma_chan *fsl_chan;
381 	struct device_link *link;
382 	struct device *pd_chan;
383 	struct device *dev;
384 	int i;
385 
386 	dev = &pdev->dev;
387 
388 	for (i = 0; i < fsl_edma->n_chans; i++) {
389 		if (fsl_edma->chan_masked & BIT(i))
390 			continue;
391 
392 		fsl_chan = &fsl_edma->chans[i];
393 
394 		pd_chan = dev_pm_domain_attach_by_id(dev, i);
395 		if (IS_ERR_OR_NULL(pd_chan)) {
396 			dev_err(dev, "Failed attach pd %d\n", i);
397 			return -EINVAL;
398 		}
399 
400 		link = device_link_add(dev, pd_chan, DL_FLAG_STATELESS |
401 					     DL_FLAG_PM_RUNTIME |
402 					     DL_FLAG_RPM_ACTIVE);
403 		if (!link) {
404 			dev_err(dev, "Failed to add device_link to %d\n", i);
405 			return -EINVAL;
406 		}
407 
408 		fsl_chan->pd_dev = pd_chan;
409 
410 		pm_runtime_use_autosuspend(fsl_chan->pd_dev);
411 		pm_runtime_set_autosuspend_delay(fsl_chan->pd_dev, 200);
412 		pm_runtime_set_active(fsl_chan->pd_dev);
413 	}
414 
415 	return 0;
416 }
417 
418 static int fsl_edma_probe(struct platform_device *pdev)
419 {
420 	const struct of_device_id *of_id =
421 			of_match_device(fsl_edma_dt_ids, &pdev->dev);
422 	struct device_node *np = pdev->dev.of_node;
423 	struct fsl_edma_engine *fsl_edma;
424 	const struct fsl_edma_drvdata *drvdata = NULL;
425 	u32 chan_mask[2] = {0, 0};
426 	struct edma_regs *regs;
427 	int chans;
428 	int ret, i;
429 
430 	if (of_id)
431 		drvdata = of_id->data;
432 	if (!drvdata) {
433 		dev_err(&pdev->dev, "unable to find driver data\n");
434 		return -EINVAL;
435 	}
436 
437 	ret = of_property_read_u32(np, "dma-channels", &chans);
438 	if (ret) {
439 		dev_err(&pdev->dev, "Can't get dma-channels.\n");
440 		return ret;
441 	}
442 
443 	fsl_edma = devm_kzalloc(&pdev->dev, struct_size(fsl_edma, chans, chans),
444 				GFP_KERNEL);
445 	if (!fsl_edma)
446 		return -ENOMEM;
447 
448 	fsl_edma->drvdata = drvdata;
449 	fsl_edma->n_chans = chans;
450 	mutex_init(&fsl_edma->fsl_edma_mutex);
451 
452 	fsl_edma->membase = devm_platform_ioremap_resource(pdev, 0);
453 	if (IS_ERR(fsl_edma->membase))
454 		return PTR_ERR(fsl_edma->membase);
455 
456 	if (!(drvdata->flags & FSL_EDMA_DRV_SPLIT_REG)) {
457 		fsl_edma_setup_regs(fsl_edma);
458 		regs = &fsl_edma->regs;
459 	}
460 
461 	if (drvdata->flags & FSL_EDMA_DRV_HAS_DMACLK) {
462 		fsl_edma->dmaclk = devm_clk_get_enabled(&pdev->dev, "dma");
463 		if (IS_ERR(fsl_edma->dmaclk)) {
464 			dev_err(&pdev->dev, "Missing DMA block clock.\n");
465 			return PTR_ERR(fsl_edma->dmaclk);
466 		}
467 	}
468 
469 	if (drvdata->flags & FSL_EDMA_DRV_HAS_CHCLK) {
470 		fsl_edma->chclk = devm_clk_get_enabled(&pdev->dev, "mp");
471 		if (IS_ERR(fsl_edma->chclk)) {
472 			dev_err(&pdev->dev, "Missing MP block clock.\n");
473 			return PTR_ERR(fsl_edma->chclk);
474 		}
475 	}
476 
477 	ret = of_property_read_variable_u32_array(np, "dma-channel-mask", chan_mask, 1, 2);
478 
479 	if (ret > 0) {
480 		fsl_edma->chan_masked = chan_mask[1];
481 		fsl_edma->chan_masked <<= 32;
482 		fsl_edma->chan_masked |= chan_mask[0];
483 	}
484 
485 	for (i = 0; i < fsl_edma->drvdata->dmamuxs; i++) {
486 		char clkname[32];
487 
488 		/* eDMAv3 mux register move to TCD area if ch_mux exist */
489 		if (drvdata->flags & FSL_EDMA_DRV_SPLIT_REG)
490 			break;
491 
492 		fsl_edma->muxbase[i] = devm_platform_ioremap_resource(pdev,
493 								      1 + i);
494 		if (IS_ERR(fsl_edma->muxbase[i])) {
495 			/* on error: disable all previously enabled clks */
496 			fsl_disable_clocks(fsl_edma, i);
497 			return PTR_ERR(fsl_edma->muxbase[i]);
498 		}
499 
500 		sprintf(clkname, "dmamux%d", i);
501 		fsl_edma->muxclk[i] = devm_clk_get_enabled(&pdev->dev, clkname);
502 		if (IS_ERR(fsl_edma->muxclk[i])) {
503 			dev_err(&pdev->dev, "Missing DMAMUX block clock.\n");
504 			/* on error: disable all previously enabled clks */
505 			return PTR_ERR(fsl_edma->muxclk[i]);
506 		}
507 	}
508 
509 	fsl_edma->big_endian = of_property_read_bool(np, "big-endian");
510 
511 	if (drvdata->flags & FSL_EDMA_DRV_HAS_PD) {
512 		ret = fsl_edma3_attach_pd(pdev, fsl_edma);
513 		if (ret)
514 			return ret;
515 	}
516 
517 	INIT_LIST_HEAD(&fsl_edma->dma_dev.channels);
518 	for (i = 0; i < fsl_edma->n_chans; i++) {
519 		struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];
520 		int len;
521 
522 		if (fsl_edma->chan_masked & BIT(i))
523 			continue;
524 
525 		snprintf(fsl_chan->chan_name, sizeof(fsl_chan->chan_name), "%s-CH%02d",
526 							   dev_name(&pdev->dev), i);
527 
528 		fsl_chan->edma = fsl_edma;
529 		fsl_chan->pm_state = RUNNING;
530 		fsl_chan->slave_id = 0;
531 		fsl_chan->idle = true;
532 		fsl_chan->dma_dir = DMA_NONE;
533 		fsl_chan->vchan.desc_free = fsl_edma_free_desc;
534 
535 		len = (drvdata->flags & FSL_EDMA_DRV_SPLIT_REG) ?
536 				offsetof(struct fsl_edma3_ch_reg, tcd) : 0;
537 		fsl_chan->tcd = fsl_edma->membase
538 				+ i * drvdata->chreg_space_sz + drvdata->chreg_off + len;
539 
540 		fsl_chan->pdev = pdev;
541 		vchan_init(&fsl_chan->vchan, &fsl_edma->dma_dev);
542 
543 		edma_write_tcdreg(fsl_chan, 0, csr);
544 		fsl_edma_chan_mux(fsl_chan, 0, false);
545 	}
546 
547 	ret = fsl_edma->drvdata->setup_irq(pdev, fsl_edma);
548 	if (ret)
549 		return ret;
550 
551 	dma_cap_set(DMA_PRIVATE, fsl_edma->dma_dev.cap_mask);
552 	dma_cap_set(DMA_SLAVE, fsl_edma->dma_dev.cap_mask);
553 	dma_cap_set(DMA_CYCLIC, fsl_edma->dma_dev.cap_mask);
554 	dma_cap_set(DMA_MEMCPY, fsl_edma->dma_dev.cap_mask);
555 
556 	fsl_edma->dma_dev.dev = &pdev->dev;
557 	fsl_edma->dma_dev.device_alloc_chan_resources
558 		= fsl_edma_alloc_chan_resources;
559 	fsl_edma->dma_dev.device_free_chan_resources
560 		= fsl_edma_free_chan_resources;
561 	fsl_edma->dma_dev.device_tx_status = fsl_edma_tx_status;
562 	fsl_edma->dma_dev.device_prep_slave_sg = fsl_edma_prep_slave_sg;
563 	fsl_edma->dma_dev.device_prep_dma_cyclic = fsl_edma_prep_dma_cyclic;
564 	fsl_edma->dma_dev.device_prep_dma_memcpy = fsl_edma_prep_memcpy;
565 	fsl_edma->dma_dev.device_config = fsl_edma_slave_config;
566 	fsl_edma->dma_dev.device_pause = fsl_edma_pause;
567 	fsl_edma->dma_dev.device_resume = fsl_edma_resume;
568 	fsl_edma->dma_dev.device_terminate_all = fsl_edma_terminate_all;
569 	fsl_edma->dma_dev.device_synchronize = fsl_edma_synchronize;
570 	fsl_edma->dma_dev.device_issue_pending = fsl_edma_issue_pending;
571 
572 	fsl_edma->dma_dev.src_addr_widths = FSL_EDMA_BUSWIDTHS;
573 	fsl_edma->dma_dev.dst_addr_widths = FSL_EDMA_BUSWIDTHS;
574 
575 	if (drvdata->flags & FSL_EDMA_DRV_BUS_8BYTE) {
576 		fsl_edma->dma_dev.src_addr_widths |= BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
577 		fsl_edma->dma_dev.dst_addr_widths |= BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
578 	}
579 
580 	fsl_edma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
581 	if (drvdata->flags & FSL_EDMA_DRV_DEV_TO_DEV)
582 		fsl_edma->dma_dev.directions |= BIT(DMA_DEV_TO_DEV);
583 
584 	fsl_edma->dma_dev.copy_align = drvdata->flags & FSL_EDMA_DRV_ALIGN_64BYTE ?
585 					DMAENGINE_ALIGN_64_BYTES :
586 					DMAENGINE_ALIGN_32_BYTES;
587 
588 	/* Per worst case 'nbytes = 1' take CITER as the max_seg_size */
589 	dma_set_max_seg_size(fsl_edma->dma_dev.dev, 0x3fff);
590 
591 	fsl_edma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
592 
593 	platform_set_drvdata(pdev, fsl_edma);
594 
595 	ret = dma_async_device_register(&fsl_edma->dma_dev);
596 	if (ret) {
597 		dev_err(&pdev->dev,
598 			"Can't register Freescale eDMA engine. (%d)\n", ret);
599 		return ret;
600 	}
601 
602 	ret = of_dma_controller_register(np,
603 			drvdata->flags & FSL_EDMA_DRV_SPLIT_REG ? fsl_edma3_xlate : fsl_edma_xlate,
604 			fsl_edma);
605 	if (ret) {
606 		dev_err(&pdev->dev,
607 			"Can't register Freescale eDMA of_dma. (%d)\n", ret);
608 		dma_async_device_unregister(&fsl_edma->dma_dev);
609 		return ret;
610 	}
611 
612 	/* enable round robin arbitration */
613 	if (!(drvdata->flags & FSL_EDMA_DRV_SPLIT_REG))
614 		edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
615 
616 	return 0;
617 }
618 
619 static int fsl_edma_remove(struct platform_device *pdev)
620 {
621 	struct device_node *np = pdev->dev.of_node;
622 	struct fsl_edma_engine *fsl_edma = platform_get_drvdata(pdev);
623 
624 	fsl_edma_irq_exit(pdev, fsl_edma);
625 	fsl_edma_cleanup_vchan(&fsl_edma->dma_dev);
626 	of_dma_controller_free(np);
627 	dma_async_device_unregister(&fsl_edma->dma_dev);
628 	fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs);
629 
630 	return 0;
631 }
632 
633 static int fsl_edma_suspend_late(struct device *dev)
634 {
635 	struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
636 	struct fsl_edma_chan *fsl_chan;
637 	unsigned long flags;
638 	int i;
639 
640 	for (i = 0; i < fsl_edma->n_chans; i++) {
641 		fsl_chan = &fsl_edma->chans[i];
642 		if (fsl_edma->chan_masked & BIT(i))
643 			continue;
644 		spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
645 		/* Make sure chan is idle or will force disable. */
646 		if (unlikely(!fsl_chan->idle)) {
647 			dev_warn(dev, "WARN: There is non-idle channel.");
648 			fsl_edma_disable_request(fsl_chan);
649 			fsl_edma_chan_mux(fsl_chan, 0, false);
650 		}
651 
652 		fsl_chan->pm_state = SUSPENDED;
653 		spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
654 	}
655 
656 	return 0;
657 }
658 
659 static int fsl_edma_resume_early(struct device *dev)
660 {
661 	struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
662 	struct fsl_edma_chan *fsl_chan;
663 	struct edma_regs *regs = &fsl_edma->regs;
664 	int i;
665 
666 	for (i = 0; i < fsl_edma->n_chans; i++) {
667 		fsl_chan = &fsl_edma->chans[i];
668 		if (fsl_edma->chan_masked & BIT(i))
669 			continue;
670 		fsl_chan->pm_state = RUNNING;
671 		edma_write_tcdreg(fsl_chan, 0, csr);
672 		if (fsl_chan->slave_id != 0)
673 			fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id, true);
674 	}
675 
676 	if (!(fsl_edma->drvdata->flags & FSL_EDMA_DRV_SPLIT_REG))
677 		edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
678 
679 	return 0;
680 }
681 
682 /*
683  * eDMA provides the service to others, so it should be suspend late
684  * and resume early. When eDMA suspend, all of the clients should stop
685  * the DMA data transmission and let the channel idle.
686  */
687 static const struct dev_pm_ops fsl_edma_pm_ops = {
688 	.suspend_late   = fsl_edma_suspend_late,
689 	.resume_early   = fsl_edma_resume_early,
690 };
691 
692 static struct platform_driver fsl_edma_driver = {
693 	.driver		= {
694 		.name	= "fsl-edma",
695 		.of_match_table = fsl_edma_dt_ids,
696 		.pm     = &fsl_edma_pm_ops,
697 	},
698 	.probe          = fsl_edma_probe,
699 	.remove		= fsl_edma_remove,
700 };
701 
702 static int __init fsl_edma_init(void)
703 {
704 	return platform_driver_register(&fsl_edma_driver);
705 }
706 subsys_initcall(fsl_edma_init);
707 
708 static void __exit fsl_edma_exit(void)
709 {
710 	platform_driver_unregister(&fsl_edma_driver);
711 }
712 module_exit(fsl_edma_exit);
713 
714 MODULE_ALIAS("platform:fsl-edma");
715 MODULE_DESCRIPTION("Freescale eDMA engine driver");
716 MODULE_LICENSE("GPL v2");
717