xref: /openbmc/linux/drivers/dma/fsl-edma-main.c (revision 2984f26a)
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 <dt-bindings/dma/fsl-edma.h>
13 #include <linux/bitfield.h>
14 #include <linux/module.h>
15 #include <linux/interrupt.h>
16 #include <linux/clk.h>
17 #include <linux/of.h>
18 #include <linux/of_device.h>
19 #include <linux/of_address.h>
20 #include <linux/of_irq.h>
21 #include <linux/of_dma.h>
22 #include <linux/dma-mapping.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/pm_domain.h>
25 
26 #include "fsl-edma-common.h"
27 
28 static void fsl_edma_synchronize(struct dma_chan *chan)
29 {
30 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
31 
32 	vchan_synchronize(&fsl_chan->vchan);
33 }
34 
35 static irqreturn_t fsl_edma_tx_handler(int irq, void *dev_id)
36 {
37 	struct fsl_edma_engine *fsl_edma = dev_id;
38 	unsigned int intr, ch;
39 	struct edma_regs *regs = &fsl_edma->regs;
40 
41 	intr = edma_readl(fsl_edma, regs->intl);
42 	if (!intr)
43 		return IRQ_NONE;
44 
45 	for (ch = 0; ch < fsl_edma->n_chans; ch++) {
46 		if (intr & (0x1 << ch)) {
47 			edma_writeb(fsl_edma, EDMA_CINT_CINT(ch), regs->cint);
48 			fsl_edma_tx_chan_handler(&fsl_edma->chans[ch]);
49 		}
50 	}
51 	return IRQ_HANDLED;
52 }
53 
54 static irqreturn_t fsl_edma3_tx_handler(int irq, void *dev_id)
55 {
56 	struct fsl_edma_chan *fsl_chan = dev_id;
57 	unsigned int intr;
58 
59 	intr = edma_readl_chreg(fsl_chan, ch_int);
60 	if (!intr)
61 		return IRQ_HANDLED;
62 
63 	edma_writel_chreg(fsl_chan, 1, ch_int);
64 
65 	fsl_edma_tx_chan_handler(fsl_chan);
66 
67 	return IRQ_HANDLED;
68 }
69 
70 static irqreturn_t fsl_edma_err_handler(int irq, void *dev_id)
71 {
72 	struct fsl_edma_engine *fsl_edma = dev_id;
73 	unsigned int err, ch;
74 	struct edma_regs *regs = &fsl_edma->regs;
75 
76 	err = edma_readl(fsl_edma, regs->errl);
77 	if (!err)
78 		return IRQ_NONE;
79 
80 	for (ch = 0; ch < fsl_edma->n_chans; ch++) {
81 		if (err & (0x1 << ch)) {
82 			fsl_edma_disable_request(&fsl_edma->chans[ch]);
83 			edma_writeb(fsl_edma, EDMA_CERR_CERR(ch), regs->cerr);
84 			fsl_edma_err_chan_handler(&fsl_edma->chans[ch]);
85 		}
86 	}
87 	return IRQ_HANDLED;
88 }
89 
90 static irqreturn_t fsl_edma_irq_handler(int irq, void *dev_id)
91 {
92 	if (fsl_edma_tx_handler(irq, dev_id) == IRQ_HANDLED)
93 		return IRQ_HANDLED;
94 
95 	return fsl_edma_err_handler(irq, dev_id);
96 }
97 
98 static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
99 		struct of_dma *ofdma)
100 {
101 	struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
102 	struct dma_chan *chan, *_chan;
103 	struct fsl_edma_chan *fsl_chan;
104 	u32 dmamux_nr = fsl_edma->drvdata->dmamuxs;
105 	unsigned long chans_per_mux = fsl_edma->n_chans / dmamux_nr;
106 
107 	if (dma_spec->args_count != 2)
108 		return NULL;
109 
110 	mutex_lock(&fsl_edma->fsl_edma_mutex);
111 	list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels, device_node) {
112 		if (chan->client_count)
113 			continue;
114 		if ((chan->chan_id / chans_per_mux) == dma_spec->args[0]) {
115 			chan = dma_get_slave_channel(chan);
116 			if (chan) {
117 				chan->device->privatecnt++;
118 				fsl_chan = to_fsl_edma_chan(chan);
119 				fsl_chan->slave_id = dma_spec->args[1];
120 				fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id,
121 						true);
122 				mutex_unlock(&fsl_edma->fsl_edma_mutex);
123 				return chan;
124 			}
125 		}
126 	}
127 	mutex_unlock(&fsl_edma->fsl_edma_mutex);
128 	return NULL;
129 }
130 
131 static struct dma_chan *fsl_edma3_xlate(struct of_phandle_args *dma_spec,
132 					struct of_dma *ofdma)
133 {
134 	struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
135 	struct dma_chan *chan, *_chan;
136 	struct fsl_edma_chan *fsl_chan;
137 	bool b_chmux;
138 	int i;
139 
140 	if (dma_spec->args_count != 3)
141 		return NULL;
142 
143 	b_chmux = !!(fsl_edma->drvdata->flags & FSL_EDMA_DRV_HAS_CHMUX);
144 
145 	mutex_lock(&fsl_edma->fsl_edma_mutex);
146 	list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels,
147 					device_node) {
148 
149 		if (chan->client_count)
150 			continue;
151 
152 		fsl_chan = to_fsl_edma_chan(chan);
153 		i = fsl_chan - fsl_edma->chans;
154 
155 		fsl_chan->priority = dma_spec->args[1];
156 		fsl_chan->is_rxchan = dma_spec->args[2] & FSL_EDMA_RX;
157 		fsl_chan->is_remote = dma_spec->args[2] & FSL_EDMA_REMOTE;
158 		fsl_chan->is_multi_fifo = dma_spec->args[2] & FSL_EDMA_MULTI_FIFO;
159 
160 		if ((dma_spec->args[2] & FSL_EDMA_EVEN_CH) && (i & 0x1))
161 			continue;
162 
163 		if ((dma_spec->args[2] & FSL_EDMA_ODD_CH) && !(i & 0x1))
164 			continue;
165 
166 		if (!b_chmux && i == dma_spec->args[0]) {
167 			chan = dma_get_slave_channel(chan);
168 			chan->device->privatecnt++;
169 			mutex_unlock(&fsl_edma->fsl_edma_mutex);
170 			return chan;
171 		} else if (b_chmux && !fsl_chan->srcid) {
172 			/* if controller support channel mux, choose a free channel */
173 			chan = dma_get_slave_channel(chan);
174 			chan->device->privatecnt++;
175 			fsl_chan->srcid = dma_spec->args[0];
176 			mutex_unlock(&fsl_edma->fsl_edma_mutex);
177 			return chan;
178 		}
179 	}
180 	mutex_unlock(&fsl_edma->fsl_edma_mutex);
181 	return NULL;
182 }
183 
184 static int
185 fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
186 {
187 	int ret;
188 
189 	edma_writel(fsl_edma, ~0, fsl_edma->regs.intl);
190 
191 	fsl_edma->txirq = platform_get_irq_byname(pdev, "edma-tx");
192 	if (fsl_edma->txirq < 0)
193 		return fsl_edma->txirq;
194 
195 	fsl_edma->errirq = platform_get_irq_byname(pdev, "edma-err");
196 	if (fsl_edma->errirq < 0)
197 		return fsl_edma->errirq;
198 
199 	if (fsl_edma->txirq == fsl_edma->errirq) {
200 		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
201 				fsl_edma_irq_handler, 0, "eDMA", fsl_edma);
202 		if (ret) {
203 			dev_err(&pdev->dev, "Can't register eDMA IRQ.\n");
204 			return ret;
205 		}
206 	} else {
207 		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
208 				fsl_edma_tx_handler, 0, "eDMA tx", fsl_edma);
209 		if (ret) {
210 			dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n");
211 			return ret;
212 		}
213 
214 		ret = devm_request_irq(&pdev->dev, fsl_edma->errirq,
215 				fsl_edma_err_handler, 0, "eDMA err", fsl_edma);
216 		if (ret) {
217 			dev_err(&pdev->dev, "Can't register eDMA err IRQ.\n");
218 			return ret;
219 		}
220 	}
221 
222 	return 0;
223 }
224 
225 static int fsl_edma3_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
226 {
227 	int ret;
228 	int i;
229 
230 	for (i = 0; i < fsl_edma->n_chans; i++) {
231 
232 		struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];
233 
234 		if (fsl_edma->chan_masked & BIT(i))
235 			continue;
236 
237 		/* request channel irq */
238 		fsl_chan->txirq = platform_get_irq(pdev, i);
239 		if (fsl_chan->txirq < 0) {
240 			dev_err(&pdev->dev, "Can't get chan %d's irq.\n", i);
241 			return  -EINVAL;
242 		}
243 
244 		ret = devm_request_irq(&pdev->dev, fsl_chan->txirq,
245 			fsl_edma3_tx_handler, IRQF_SHARED,
246 			fsl_chan->chan_name, fsl_chan);
247 		if (ret) {
248 			dev_err(&pdev->dev, "Can't register chan%d's IRQ.\n", i);
249 			return -EINVAL;
250 		}
251 	}
252 
253 	return 0;
254 }
255 
256 static int
257 fsl_edma2_irq_init(struct platform_device *pdev,
258 		   struct fsl_edma_engine *fsl_edma)
259 {
260 	int i, ret, irq;
261 	int count;
262 
263 	edma_writel(fsl_edma, ~0, fsl_edma->regs.intl);
264 
265 	count = platform_irq_count(pdev);
266 	dev_dbg(&pdev->dev, "%s Found %d interrupts\r\n", __func__, count);
267 	if (count <= 2) {
268 		dev_err(&pdev->dev, "Interrupts in DTS not correct.\n");
269 		return -EINVAL;
270 	}
271 	/*
272 	 * 16 channel independent interrupts + 1 error interrupt on i.mx7ulp.
273 	 * 2 channel share one interrupt, for example, ch0/ch16, ch1/ch17...
274 	 * For now, just simply request irq without IRQF_SHARED flag, since 16
275 	 * channels are enough on i.mx7ulp whose M4 domain own some peripherals.
276 	 */
277 	for (i = 0; i < count; i++) {
278 		irq = platform_get_irq(pdev, i);
279 		if (irq < 0)
280 			return -ENXIO;
281 
282 		/* The last IRQ is for eDMA err */
283 		if (i == count - 1)
284 			ret = devm_request_irq(&pdev->dev, irq,
285 						fsl_edma_err_handler,
286 						0, "eDMA2-ERR", fsl_edma);
287 		else
288 			ret = devm_request_irq(&pdev->dev, irq,
289 						fsl_edma_tx_handler, 0,
290 						fsl_edma->chans[i].chan_name,
291 						fsl_edma);
292 		if (ret)
293 			return ret;
294 	}
295 
296 	return 0;
297 }
298 
299 static void fsl_edma_irq_exit(
300 		struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
301 {
302 	if (fsl_edma->txirq == fsl_edma->errirq) {
303 		devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
304 	} else {
305 		devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
306 		devm_free_irq(&pdev->dev, fsl_edma->errirq, fsl_edma);
307 	}
308 }
309 
310 static void fsl_disable_clocks(struct fsl_edma_engine *fsl_edma, int nr_clocks)
311 {
312 	int i;
313 
314 	for (i = 0; i < nr_clocks; i++)
315 		clk_disable_unprepare(fsl_edma->muxclk[i]);
316 }
317 
318 static struct fsl_edma_drvdata vf610_data = {
319 	.dmamuxs = DMAMUX_NR,
320 	.flags = FSL_EDMA_DRV_WRAP_IO,
321 	.chreg_off = EDMA_TCD,
322 	.chreg_space_sz = sizeof(struct fsl_edma_hw_tcd),
323 	.setup_irq = fsl_edma_irq_init,
324 };
325 
326 static struct fsl_edma_drvdata ls1028a_data = {
327 	.dmamuxs = DMAMUX_NR,
328 	.flags = FSL_EDMA_DRV_MUX_SWAP | FSL_EDMA_DRV_WRAP_IO,
329 	.chreg_off = EDMA_TCD,
330 	.chreg_space_sz = sizeof(struct fsl_edma_hw_tcd),
331 	.setup_irq = fsl_edma_irq_init,
332 };
333 
334 static struct fsl_edma_drvdata imx7ulp_data = {
335 	.dmamuxs = 1,
336 	.chreg_off = EDMA_TCD,
337 	.chreg_space_sz = sizeof(struct fsl_edma_hw_tcd),
338 	.flags = FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_CONFIG32,
339 	.setup_irq = fsl_edma2_irq_init,
340 };
341 
342 static struct fsl_edma_drvdata imx8qm_data = {
343 	.flags = FSL_EDMA_DRV_HAS_PD | FSL_EDMA_DRV_EDMA3,
344 	.chreg_space_sz = 0x10000,
345 	.chreg_off = 0x10000,
346 	.setup_irq = fsl_edma3_irq_init,
347 };
348 
349 static struct fsl_edma_drvdata imx8qm_audio_data = {
350 	.flags = FSL_EDMA_DRV_QUIRK_SWAPPED | FSL_EDMA_DRV_HAS_PD | FSL_EDMA_DRV_EDMA3,
351 	.chreg_space_sz = 0x10000,
352 	.chreg_off = 0x10000,
353 	.setup_irq = fsl_edma3_irq_init,
354 };
355 
356 static struct fsl_edma_drvdata imx93_data3 = {
357 	.flags = FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_EDMA3,
358 	.chreg_space_sz = 0x10000,
359 	.chreg_off = 0x10000,
360 	.setup_irq = fsl_edma3_irq_init,
361 };
362 
363 static struct fsl_edma_drvdata imx93_data4 = {
364 	.flags = FSL_EDMA_DRV_HAS_CHMUX | FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_EDMA4,
365 	.chreg_space_sz = 0x8000,
366 	.chreg_off = 0x10000,
367 	.setup_irq = fsl_edma3_irq_init,
368 };
369 
370 static const struct of_device_id fsl_edma_dt_ids[] = {
371 	{ .compatible = "fsl,vf610-edma", .data = &vf610_data},
372 	{ .compatible = "fsl,ls1028a-edma", .data = &ls1028a_data},
373 	{ .compatible = "fsl,imx7ulp-edma", .data = &imx7ulp_data},
374 	{ .compatible = "fsl,imx8qm-edma", .data = &imx8qm_data},
375 	{ .compatible = "fsl,imx8qm-adma", .data = &imx8qm_audio_data},
376 	{ .compatible = "fsl,imx93-edma3", .data = &imx93_data3},
377 	{ .compatible = "fsl,imx93-edma4", .data = &imx93_data4},
378 	{ /* sentinel */ }
379 };
380 MODULE_DEVICE_TABLE(of, fsl_edma_dt_ids);
381 
382 static int fsl_edma3_attach_pd(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
383 {
384 	struct fsl_edma_chan *fsl_chan;
385 	struct device_link *link;
386 	struct device *pd_chan;
387 	struct device *dev;
388 	int i;
389 
390 	dev = &pdev->dev;
391 
392 	for (i = 0; i < fsl_edma->n_chans; i++) {
393 		if (fsl_edma->chan_masked & BIT(i))
394 			continue;
395 
396 		fsl_chan = &fsl_edma->chans[i];
397 
398 		pd_chan = dev_pm_domain_attach_by_id(dev, i);
399 		if (IS_ERR_OR_NULL(pd_chan)) {
400 			dev_err(dev, "Failed attach pd %d\n", i);
401 			return -EINVAL;
402 		}
403 
404 		link = device_link_add(dev, pd_chan, DL_FLAG_STATELESS |
405 					     DL_FLAG_PM_RUNTIME |
406 					     DL_FLAG_RPM_ACTIVE);
407 		if (!link) {
408 			dev_err(dev, "Failed to add device_link to %d\n", i);
409 			return -EINVAL;
410 		}
411 
412 		fsl_chan->pd_dev = pd_chan;
413 
414 		pm_runtime_use_autosuspend(fsl_chan->pd_dev);
415 		pm_runtime_set_autosuspend_delay(fsl_chan->pd_dev, 200);
416 		pm_runtime_set_active(fsl_chan->pd_dev);
417 	}
418 
419 	return 0;
420 }
421 
422 static int fsl_edma_probe(struct platform_device *pdev)
423 {
424 	const struct of_device_id *of_id =
425 			of_match_device(fsl_edma_dt_ids, &pdev->dev);
426 	struct device_node *np = pdev->dev.of_node;
427 	struct fsl_edma_engine *fsl_edma;
428 	const struct fsl_edma_drvdata *drvdata = NULL;
429 	u32 chan_mask[2] = {0, 0};
430 	struct edma_regs *regs;
431 	int chans;
432 	int ret, i;
433 
434 	if (of_id)
435 		drvdata = of_id->data;
436 	if (!drvdata) {
437 		dev_err(&pdev->dev, "unable to find driver data\n");
438 		return -EINVAL;
439 	}
440 
441 	ret = of_property_read_u32(np, "dma-channels", &chans);
442 	if (ret) {
443 		dev_err(&pdev->dev, "Can't get dma-channels.\n");
444 		return ret;
445 	}
446 
447 	fsl_edma = devm_kzalloc(&pdev->dev, struct_size(fsl_edma, chans, chans),
448 				GFP_KERNEL);
449 	if (!fsl_edma)
450 		return -ENOMEM;
451 
452 	fsl_edma->drvdata = drvdata;
453 	fsl_edma->n_chans = chans;
454 	mutex_init(&fsl_edma->fsl_edma_mutex);
455 
456 	fsl_edma->membase = devm_platform_ioremap_resource(pdev, 0);
457 	if (IS_ERR(fsl_edma->membase))
458 		return PTR_ERR(fsl_edma->membase);
459 
460 	if (!(drvdata->flags & FSL_EDMA_DRV_SPLIT_REG)) {
461 		fsl_edma_setup_regs(fsl_edma);
462 		regs = &fsl_edma->regs;
463 	}
464 
465 	if (drvdata->flags & FSL_EDMA_DRV_HAS_DMACLK) {
466 		fsl_edma->dmaclk = devm_clk_get_enabled(&pdev->dev, "dma");
467 		if (IS_ERR(fsl_edma->dmaclk)) {
468 			dev_err(&pdev->dev, "Missing DMA block clock.\n");
469 			return PTR_ERR(fsl_edma->dmaclk);
470 		}
471 	}
472 
473 	if (drvdata->flags & FSL_EDMA_DRV_HAS_CHCLK) {
474 		fsl_edma->chclk = devm_clk_get_enabled(&pdev->dev, "mp");
475 		if (IS_ERR(fsl_edma->chclk)) {
476 			dev_err(&pdev->dev, "Missing MP block clock.\n");
477 			return PTR_ERR(fsl_edma->chclk);
478 		}
479 	}
480 
481 	ret = of_property_read_variable_u32_array(np, "dma-channel-mask", chan_mask, 1, 2);
482 
483 	if (ret > 0) {
484 		fsl_edma->chan_masked = chan_mask[1];
485 		fsl_edma->chan_masked <<= 32;
486 		fsl_edma->chan_masked |= chan_mask[0];
487 	}
488 
489 	for (i = 0; i < fsl_edma->drvdata->dmamuxs; i++) {
490 		char clkname[32];
491 
492 		/* eDMAv3 mux register move to TCD area if ch_mux exist */
493 		if (drvdata->flags & FSL_EDMA_DRV_SPLIT_REG)
494 			break;
495 
496 		fsl_edma->muxbase[i] = devm_platform_ioremap_resource(pdev,
497 								      1 + i);
498 		if (IS_ERR(fsl_edma->muxbase[i])) {
499 			/* on error: disable all previously enabled clks */
500 			fsl_disable_clocks(fsl_edma, i);
501 			return PTR_ERR(fsl_edma->muxbase[i]);
502 		}
503 
504 		sprintf(clkname, "dmamux%d", i);
505 		fsl_edma->muxclk[i] = devm_clk_get_enabled(&pdev->dev, clkname);
506 		if (IS_ERR(fsl_edma->muxclk[i])) {
507 			dev_err(&pdev->dev, "Missing DMAMUX block clock.\n");
508 			/* on error: disable all previously enabled clks */
509 			return PTR_ERR(fsl_edma->muxclk[i]);
510 		}
511 	}
512 
513 	fsl_edma->big_endian = of_property_read_bool(np, "big-endian");
514 
515 	if (drvdata->flags & FSL_EDMA_DRV_HAS_PD) {
516 		ret = fsl_edma3_attach_pd(pdev, fsl_edma);
517 		if (ret)
518 			return ret;
519 	}
520 
521 	INIT_LIST_HEAD(&fsl_edma->dma_dev.channels);
522 	for (i = 0; i < fsl_edma->n_chans; i++) {
523 		struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];
524 		int len;
525 
526 		if (fsl_edma->chan_masked & BIT(i))
527 			continue;
528 
529 		snprintf(fsl_chan->chan_name, sizeof(fsl_chan->chan_name), "%s-CH%02d",
530 							   dev_name(&pdev->dev), i);
531 
532 		fsl_chan->edma = fsl_edma;
533 		fsl_chan->pm_state = RUNNING;
534 		fsl_chan->slave_id = 0;
535 		fsl_chan->idle = true;
536 		fsl_chan->dma_dir = DMA_NONE;
537 		fsl_chan->vchan.desc_free = fsl_edma_free_desc;
538 
539 		len = (drvdata->flags & FSL_EDMA_DRV_SPLIT_REG) ?
540 				offsetof(struct fsl_edma3_ch_reg, tcd) : 0;
541 		fsl_chan->tcd = fsl_edma->membase
542 				+ i * drvdata->chreg_space_sz + drvdata->chreg_off + len;
543 
544 		fsl_chan->pdev = pdev;
545 		vchan_init(&fsl_chan->vchan, &fsl_edma->dma_dev);
546 
547 		edma_write_tcdreg(fsl_chan, 0, csr);
548 		fsl_edma_chan_mux(fsl_chan, 0, false);
549 	}
550 
551 	ret = fsl_edma->drvdata->setup_irq(pdev, fsl_edma);
552 	if (ret)
553 		return ret;
554 
555 	dma_cap_set(DMA_PRIVATE, fsl_edma->dma_dev.cap_mask);
556 	dma_cap_set(DMA_SLAVE, fsl_edma->dma_dev.cap_mask);
557 	dma_cap_set(DMA_CYCLIC, fsl_edma->dma_dev.cap_mask);
558 	dma_cap_set(DMA_MEMCPY, fsl_edma->dma_dev.cap_mask);
559 
560 	fsl_edma->dma_dev.dev = &pdev->dev;
561 	fsl_edma->dma_dev.device_alloc_chan_resources
562 		= fsl_edma_alloc_chan_resources;
563 	fsl_edma->dma_dev.device_free_chan_resources
564 		= fsl_edma_free_chan_resources;
565 	fsl_edma->dma_dev.device_tx_status = fsl_edma_tx_status;
566 	fsl_edma->dma_dev.device_prep_slave_sg = fsl_edma_prep_slave_sg;
567 	fsl_edma->dma_dev.device_prep_dma_cyclic = fsl_edma_prep_dma_cyclic;
568 	fsl_edma->dma_dev.device_prep_dma_memcpy = fsl_edma_prep_memcpy;
569 	fsl_edma->dma_dev.device_config = fsl_edma_slave_config;
570 	fsl_edma->dma_dev.device_pause = fsl_edma_pause;
571 	fsl_edma->dma_dev.device_resume = fsl_edma_resume;
572 	fsl_edma->dma_dev.device_terminate_all = fsl_edma_terminate_all;
573 	fsl_edma->dma_dev.device_synchronize = fsl_edma_synchronize;
574 	fsl_edma->dma_dev.device_issue_pending = fsl_edma_issue_pending;
575 
576 	fsl_edma->dma_dev.src_addr_widths = FSL_EDMA_BUSWIDTHS;
577 	fsl_edma->dma_dev.dst_addr_widths = FSL_EDMA_BUSWIDTHS;
578 
579 	if (drvdata->flags & FSL_EDMA_DRV_BUS_8BYTE) {
580 		fsl_edma->dma_dev.src_addr_widths |= BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
581 		fsl_edma->dma_dev.dst_addr_widths |= BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
582 	}
583 
584 	fsl_edma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
585 	if (drvdata->flags & FSL_EDMA_DRV_DEV_TO_DEV)
586 		fsl_edma->dma_dev.directions |= BIT(DMA_DEV_TO_DEV);
587 
588 	fsl_edma->dma_dev.copy_align = drvdata->flags & FSL_EDMA_DRV_ALIGN_64BYTE ?
589 					DMAENGINE_ALIGN_64_BYTES :
590 					DMAENGINE_ALIGN_32_BYTES;
591 
592 	/* Per worst case 'nbytes = 1' take CITER as the max_seg_size */
593 	dma_set_max_seg_size(fsl_edma->dma_dev.dev,
594 			     FIELD_GET(EDMA_TCD_ITER_MASK, EDMA_TCD_ITER_MASK));
595 
596 	fsl_edma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
597 
598 	platform_set_drvdata(pdev, fsl_edma);
599 
600 	ret = dma_async_device_register(&fsl_edma->dma_dev);
601 	if (ret) {
602 		dev_err(&pdev->dev,
603 			"Can't register Freescale eDMA engine. (%d)\n", ret);
604 		return ret;
605 	}
606 
607 	ret = of_dma_controller_register(np,
608 			drvdata->flags & FSL_EDMA_DRV_SPLIT_REG ? fsl_edma3_xlate : fsl_edma_xlate,
609 			fsl_edma);
610 	if (ret) {
611 		dev_err(&pdev->dev,
612 			"Can't register Freescale eDMA of_dma. (%d)\n", ret);
613 		dma_async_device_unregister(&fsl_edma->dma_dev);
614 		return ret;
615 	}
616 
617 	/* enable round robin arbitration */
618 	if (!(drvdata->flags & FSL_EDMA_DRV_SPLIT_REG))
619 		edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
620 
621 	return 0;
622 }
623 
624 static int fsl_edma_remove(struct platform_device *pdev)
625 {
626 	struct device_node *np = pdev->dev.of_node;
627 	struct fsl_edma_engine *fsl_edma = platform_get_drvdata(pdev);
628 
629 	fsl_edma_irq_exit(pdev, fsl_edma);
630 	fsl_edma_cleanup_vchan(&fsl_edma->dma_dev);
631 	of_dma_controller_free(np);
632 	dma_async_device_unregister(&fsl_edma->dma_dev);
633 	fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs);
634 
635 	return 0;
636 }
637 
638 static int fsl_edma_suspend_late(struct device *dev)
639 {
640 	struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
641 	struct fsl_edma_chan *fsl_chan;
642 	unsigned long flags;
643 	int i;
644 
645 	for (i = 0; i < fsl_edma->n_chans; i++) {
646 		fsl_chan = &fsl_edma->chans[i];
647 		if (fsl_edma->chan_masked & BIT(i))
648 			continue;
649 		spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
650 		/* Make sure chan is idle or will force disable. */
651 		if (unlikely(!fsl_chan->idle)) {
652 			dev_warn(dev, "WARN: There is non-idle channel.");
653 			fsl_edma_disable_request(fsl_chan);
654 			fsl_edma_chan_mux(fsl_chan, 0, false);
655 		}
656 
657 		fsl_chan->pm_state = SUSPENDED;
658 		spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
659 	}
660 
661 	return 0;
662 }
663 
664 static int fsl_edma_resume_early(struct device *dev)
665 {
666 	struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
667 	struct fsl_edma_chan *fsl_chan;
668 	struct edma_regs *regs = &fsl_edma->regs;
669 	int i;
670 
671 	for (i = 0; i < fsl_edma->n_chans; i++) {
672 		fsl_chan = &fsl_edma->chans[i];
673 		if (fsl_edma->chan_masked & BIT(i))
674 			continue;
675 		fsl_chan->pm_state = RUNNING;
676 		edma_write_tcdreg(fsl_chan, 0, csr);
677 		if (fsl_chan->slave_id != 0)
678 			fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id, true);
679 	}
680 
681 	if (!(fsl_edma->drvdata->flags & FSL_EDMA_DRV_SPLIT_REG))
682 		edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
683 
684 	return 0;
685 }
686 
687 /*
688  * eDMA provides the service to others, so it should be suspend late
689  * and resume early. When eDMA suspend, all of the clients should stop
690  * the DMA data transmission and let the channel idle.
691  */
692 static const struct dev_pm_ops fsl_edma_pm_ops = {
693 	.suspend_late   = fsl_edma_suspend_late,
694 	.resume_early   = fsl_edma_resume_early,
695 };
696 
697 static struct platform_driver fsl_edma_driver = {
698 	.driver		= {
699 		.name	= "fsl-edma",
700 		.of_match_table = fsl_edma_dt_ids,
701 		.pm     = &fsl_edma_pm_ops,
702 	},
703 	.probe          = fsl_edma_probe,
704 	.remove		= fsl_edma_remove,
705 };
706 
707 static int __init fsl_edma_init(void)
708 {
709 	return platform_driver_register(&fsl_edma_driver);
710 }
711 subsys_initcall(fsl_edma_init);
712 
713 static void __exit fsl_edma_exit(void)
714 {
715 	platform_driver_unregister(&fsl_edma_driver);
716 }
717 module_exit(fsl_edma_exit);
718 
719 MODULE_ALIAS("platform:fsl-edma");
720 MODULE_DESCRIPTION("Freescale eDMA engine driver");
721 MODULE_LICENSE("GPL v2");
722