xref: /openbmc/linux/drivers/dma/fsl-edma-main.c (revision 177fe2a7)
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 #define ARGS_EVEN_CH                    BIT(3)
30 #define ARGS_ODD_CH                     BIT(4)
31 
32 static void fsl_edma_synchronize(struct dma_chan *chan)
33 {
34 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
35 
36 	vchan_synchronize(&fsl_chan->vchan);
37 }
38 
39 static irqreturn_t fsl_edma_tx_handler(int irq, void *dev_id)
40 {
41 	struct fsl_edma_engine *fsl_edma = dev_id;
42 	unsigned int intr, ch;
43 	struct edma_regs *regs = &fsl_edma->regs;
44 
45 	intr = edma_readl(fsl_edma, regs->intl);
46 	if (!intr)
47 		return IRQ_NONE;
48 
49 	for (ch = 0; ch < fsl_edma->n_chans; ch++) {
50 		if (intr & (0x1 << ch)) {
51 			edma_writeb(fsl_edma, EDMA_CINT_CINT(ch), regs->cint);
52 			fsl_edma_tx_chan_handler(&fsl_edma->chans[ch]);
53 		}
54 	}
55 	return IRQ_HANDLED;
56 }
57 
58 static irqreturn_t fsl_edma3_tx_handler(int irq, void *dev_id)
59 {
60 	struct fsl_edma_chan *fsl_chan = dev_id;
61 	unsigned int intr;
62 
63 	intr = edma_readl_chreg(fsl_chan, ch_int);
64 	if (!intr)
65 		return IRQ_HANDLED;
66 
67 	edma_writel_chreg(fsl_chan, 1, ch_int);
68 
69 	fsl_edma_tx_chan_handler(fsl_chan);
70 
71 	return IRQ_HANDLED;
72 }
73 
74 static irqreturn_t fsl_edma_err_handler(int irq, void *dev_id)
75 {
76 	struct fsl_edma_engine *fsl_edma = dev_id;
77 	unsigned int err, ch;
78 	struct edma_regs *regs = &fsl_edma->regs;
79 
80 	err = edma_readl(fsl_edma, regs->errl);
81 	if (!err)
82 		return IRQ_NONE;
83 
84 	for (ch = 0; ch < fsl_edma->n_chans; ch++) {
85 		if (err & (0x1 << ch)) {
86 			fsl_edma_disable_request(&fsl_edma->chans[ch]);
87 			edma_writeb(fsl_edma, EDMA_CERR_CERR(ch), regs->cerr);
88 			fsl_edma_err_chan_handler(&fsl_edma->chans[ch]);
89 		}
90 	}
91 	return IRQ_HANDLED;
92 }
93 
94 static irqreturn_t fsl_edma_irq_handler(int irq, void *dev_id)
95 {
96 	if (fsl_edma_tx_handler(irq, dev_id) == IRQ_HANDLED)
97 		return IRQ_HANDLED;
98 
99 	return fsl_edma_err_handler(irq, dev_id);
100 }
101 
102 static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
103 		struct of_dma *ofdma)
104 {
105 	struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
106 	struct dma_chan *chan, *_chan;
107 	struct fsl_edma_chan *fsl_chan;
108 	u32 dmamux_nr = fsl_edma->drvdata->dmamuxs;
109 	unsigned long chans_per_mux = fsl_edma->n_chans / dmamux_nr;
110 
111 	if (dma_spec->args_count != 2)
112 		return NULL;
113 
114 	mutex_lock(&fsl_edma->fsl_edma_mutex);
115 	list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels, device_node) {
116 		if (chan->client_count)
117 			continue;
118 		if ((chan->chan_id / chans_per_mux) == dma_spec->args[0]) {
119 			chan = dma_get_slave_channel(chan);
120 			if (chan) {
121 				chan->device->privatecnt++;
122 				fsl_chan = to_fsl_edma_chan(chan);
123 				fsl_chan->slave_id = dma_spec->args[1];
124 				fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id,
125 						true);
126 				mutex_unlock(&fsl_edma->fsl_edma_mutex);
127 				return chan;
128 			}
129 		}
130 	}
131 	mutex_unlock(&fsl_edma->fsl_edma_mutex);
132 	return NULL;
133 }
134 
135 static struct dma_chan *fsl_edma3_xlate(struct of_phandle_args *dma_spec,
136 					struct of_dma *ofdma)
137 {
138 	struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
139 	struct dma_chan *chan, *_chan;
140 	struct fsl_edma_chan *fsl_chan;
141 	bool b_chmux;
142 	int i;
143 
144 	if (dma_spec->args_count != 3)
145 		return NULL;
146 
147 	b_chmux = !!(fsl_edma->drvdata->flags & FSL_EDMA_DRV_HAS_CHMUX);
148 
149 	mutex_lock(&fsl_edma->fsl_edma_mutex);
150 	list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels,
151 					device_node) {
152 
153 		if (chan->client_count)
154 			continue;
155 
156 		fsl_chan = to_fsl_edma_chan(chan);
157 		i = fsl_chan - fsl_edma->chans;
158 
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 ((dma_spec->args[2] & ARGS_EVEN_CH) && (i & 0x1))
165 			continue;
166 
167 		if ((dma_spec->args[2] & ARGS_ODD_CH) && !(i & 0x1))
168 			continue;
169 
170 		if (!b_chmux && i == dma_spec->args[0]) {
171 			chan = dma_get_slave_channel(chan);
172 			chan->device->privatecnt++;
173 			mutex_unlock(&fsl_edma->fsl_edma_mutex);
174 			return chan;
175 		} else if (b_chmux && !fsl_chan->srcid) {
176 			/* if controller support channel mux, choose a free channel */
177 			chan = dma_get_slave_channel(chan);
178 			chan->device->privatecnt++;
179 			fsl_chan->srcid = dma_spec->args[0];
180 			mutex_unlock(&fsl_edma->fsl_edma_mutex);
181 			return chan;
182 		}
183 	}
184 	mutex_unlock(&fsl_edma->fsl_edma_mutex);
185 	return NULL;
186 }
187 
188 static int
189 fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
190 {
191 	int ret;
192 
193 	edma_writel(fsl_edma, ~0, fsl_edma->regs.intl);
194 
195 	fsl_edma->txirq = platform_get_irq_byname(pdev, "edma-tx");
196 	if (fsl_edma->txirq < 0)
197 		return fsl_edma->txirq;
198 
199 	fsl_edma->errirq = platform_get_irq_byname(pdev, "edma-err");
200 	if (fsl_edma->errirq < 0)
201 		return fsl_edma->errirq;
202 
203 	if (fsl_edma->txirq == fsl_edma->errirq) {
204 		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
205 				fsl_edma_irq_handler, 0, "eDMA", fsl_edma);
206 		if (ret) {
207 			dev_err(&pdev->dev, "Can't register eDMA IRQ.\n");
208 			return ret;
209 		}
210 	} else {
211 		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
212 				fsl_edma_tx_handler, 0, "eDMA tx", fsl_edma);
213 		if (ret) {
214 			dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n");
215 			return ret;
216 		}
217 
218 		ret = devm_request_irq(&pdev->dev, fsl_edma->errirq,
219 				fsl_edma_err_handler, 0, "eDMA err", fsl_edma);
220 		if (ret) {
221 			dev_err(&pdev->dev, "Can't register eDMA err IRQ.\n");
222 			return ret;
223 		}
224 	}
225 
226 	return 0;
227 }
228 
229 static int fsl_edma3_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
230 {
231 	int ret;
232 	int i;
233 
234 	for (i = 0; i < fsl_edma->n_chans; i++) {
235 
236 		struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];
237 
238 		if (fsl_edma->chan_masked & BIT(i))
239 			continue;
240 
241 		/* request channel irq */
242 		fsl_chan->txirq = platform_get_irq(pdev, i);
243 		if (fsl_chan->txirq < 0) {
244 			dev_err(&pdev->dev, "Can't get chan %d's irq.\n", i);
245 			return  -EINVAL;
246 		}
247 
248 		ret = devm_request_irq(&pdev->dev, fsl_chan->txirq,
249 			fsl_edma3_tx_handler, IRQF_SHARED,
250 			fsl_chan->chan_name, fsl_chan);
251 		if (ret) {
252 			dev_err(&pdev->dev, "Can't register chan%d's IRQ.\n", i);
253 			return -EINVAL;
254 		}
255 	}
256 
257 	return 0;
258 }
259 
260 static int
261 fsl_edma2_irq_init(struct platform_device *pdev,
262 		   struct fsl_edma_engine *fsl_edma)
263 {
264 	int i, ret, irq;
265 	int count;
266 
267 	edma_writel(fsl_edma, ~0, fsl_edma->regs.intl);
268 
269 	count = platform_irq_count(pdev);
270 	dev_dbg(&pdev->dev, "%s Found %d interrupts\r\n", __func__, count);
271 	if (count <= 2) {
272 		dev_err(&pdev->dev, "Interrupts in DTS not correct.\n");
273 		return -EINVAL;
274 	}
275 	/*
276 	 * 16 channel independent interrupts + 1 error interrupt on i.mx7ulp.
277 	 * 2 channel share one interrupt, for example, ch0/ch16, ch1/ch17...
278 	 * For now, just simply request irq without IRQF_SHARED flag, since 16
279 	 * channels are enough on i.mx7ulp whose M4 domain own some peripherals.
280 	 */
281 	for (i = 0; i < count; i++) {
282 		irq = platform_get_irq(pdev, i);
283 		if (irq < 0)
284 			return -ENXIO;
285 
286 		/* The last IRQ is for eDMA err */
287 		if (i == count - 1)
288 			ret = devm_request_irq(&pdev->dev, irq,
289 						fsl_edma_err_handler,
290 						0, "eDMA2-ERR", fsl_edma);
291 		else
292 			ret = devm_request_irq(&pdev->dev, irq,
293 						fsl_edma_tx_handler, 0,
294 						fsl_edma->chans[i].chan_name,
295 						fsl_edma);
296 		if (ret)
297 			return ret;
298 	}
299 
300 	return 0;
301 }
302 
303 static void fsl_edma_irq_exit(
304 		struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
305 {
306 	if (fsl_edma->txirq == fsl_edma->errirq) {
307 		devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
308 	} else {
309 		devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
310 		devm_free_irq(&pdev->dev, fsl_edma->errirq, fsl_edma);
311 	}
312 }
313 
314 static void fsl_disable_clocks(struct fsl_edma_engine *fsl_edma, int nr_clocks)
315 {
316 	int i;
317 
318 	for (i = 0; i < nr_clocks; i++)
319 		clk_disable_unprepare(fsl_edma->muxclk[i]);
320 }
321 
322 static struct fsl_edma_drvdata vf610_data = {
323 	.dmamuxs = DMAMUX_NR,
324 	.flags = 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 ls1028a_data = {
331 	.dmamuxs = DMAMUX_NR,
332 	.flags = FSL_EDMA_DRV_MUX_SWAP | FSL_EDMA_DRV_WRAP_IO,
333 	.chreg_off = EDMA_TCD,
334 	.chreg_space_sz = sizeof(struct fsl_edma_hw_tcd),
335 	.setup_irq = fsl_edma_irq_init,
336 };
337 
338 static struct fsl_edma_drvdata imx7ulp_data = {
339 	.dmamuxs = 1,
340 	.chreg_off = EDMA_TCD,
341 	.chreg_space_sz = sizeof(struct fsl_edma_hw_tcd),
342 	.flags = FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_CONFIG32,
343 	.setup_irq = fsl_edma2_irq_init,
344 };
345 
346 static struct fsl_edma_drvdata imx8qm_data = {
347 	.flags = FSL_EDMA_DRV_HAS_PD | FSL_EDMA_DRV_EDMA3,
348 	.chreg_space_sz = 0x10000,
349 	.chreg_off = 0x10000,
350 	.setup_irq = fsl_edma3_irq_init,
351 };
352 
353 static struct fsl_edma_drvdata imx8qm_audio_data = {
354 	.flags = FSL_EDMA_DRV_QUIRK_SWAPPED | FSL_EDMA_DRV_HAS_PD | FSL_EDMA_DRV_EDMA3,
355 	.chreg_space_sz = 0x10000,
356 	.chreg_off = 0x10000,
357 	.setup_irq = fsl_edma3_irq_init,
358 };
359 
360 static struct fsl_edma_drvdata imx93_data3 = {
361 	.flags = FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_EDMA3,
362 	.chreg_space_sz = 0x10000,
363 	.chreg_off = 0x10000,
364 	.setup_irq = fsl_edma3_irq_init,
365 };
366 
367 static struct fsl_edma_drvdata imx93_data4 = {
368 	.flags = FSL_EDMA_DRV_HAS_CHMUX | FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_EDMA4,
369 	.chreg_space_sz = 0x8000,
370 	.chreg_off = 0x10000,
371 	.setup_irq = fsl_edma3_irq_init,
372 };
373 
374 static const struct of_device_id fsl_edma_dt_ids[] = {
375 	{ .compatible = "fsl,vf610-edma", .data = &vf610_data},
376 	{ .compatible = "fsl,ls1028a-edma", .data = &ls1028a_data},
377 	{ .compatible = "fsl,imx7ulp-edma", .data = &imx7ulp_data},
378 	{ .compatible = "fsl,imx8qm-edma", .data = &imx8qm_data},
379 	{ .compatible = "fsl,imx8qm-adma", .data = &imx8qm_audio_data},
380 	{ .compatible = "fsl,imx93-edma3", .data = &imx93_data3},
381 	{ .compatible = "fsl,imx93-edma4", .data = &imx93_data4},
382 	{ /* sentinel */ }
383 };
384 MODULE_DEVICE_TABLE(of, fsl_edma_dt_ids);
385 
386 static int fsl_edma3_attach_pd(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
387 {
388 	struct fsl_edma_chan *fsl_chan;
389 	struct device_link *link;
390 	struct device *pd_chan;
391 	struct device *dev;
392 	int i;
393 
394 	dev = &pdev->dev;
395 
396 	for (i = 0; i < fsl_edma->n_chans; i++) {
397 		if (fsl_edma->chan_masked & BIT(i))
398 			continue;
399 
400 		fsl_chan = &fsl_edma->chans[i];
401 
402 		pd_chan = dev_pm_domain_attach_by_id(dev, i);
403 		if (IS_ERR_OR_NULL(pd_chan)) {
404 			dev_err(dev, "Failed attach pd %d\n", i);
405 			return -EINVAL;
406 		}
407 
408 		link = device_link_add(dev, pd_chan, DL_FLAG_STATELESS |
409 					     DL_FLAG_PM_RUNTIME |
410 					     DL_FLAG_RPM_ACTIVE);
411 		if (!link) {
412 			dev_err(dev, "Failed to add device_link to %d\n", i);
413 			return -EINVAL;
414 		}
415 
416 		fsl_chan->pd_dev = pd_chan;
417 
418 		pm_runtime_use_autosuspend(fsl_chan->pd_dev);
419 		pm_runtime_set_autosuspend_delay(fsl_chan->pd_dev, 200);
420 		pm_runtime_set_active(fsl_chan->pd_dev);
421 	}
422 
423 	return 0;
424 }
425 
426 static int fsl_edma_probe(struct platform_device *pdev)
427 {
428 	const struct of_device_id *of_id =
429 			of_match_device(fsl_edma_dt_ids, &pdev->dev);
430 	struct device_node *np = pdev->dev.of_node;
431 	struct fsl_edma_engine *fsl_edma;
432 	const struct fsl_edma_drvdata *drvdata = NULL;
433 	u32 chan_mask[2] = {0, 0};
434 	struct edma_regs *regs;
435 	int chans;
436 	int ret, i;
437 
438 	if (of_id)
439 		drvdata = of_id->data;
440 	if (!drvdata) {
441 		dev_err(&pdev->dev, "unable to find driver data\n");
442 		return -EINVAL;
443 	}
444 
445 	ret = of_property_read_u32(np, "dma-channels", &chans);
446 	if (ret) {
447 		dev_err(&pdev->dev, "Can't get dma-channels.\n");
448 		return ret;
449 	}
450 
451 	fsl_edma = devm_kzalloc(&pdev->dev, struct_size(fsl_edma, chans, chans),
452 				GFP_KERNEL);
453 	if (!fsl_edma)
454 		return -ENOMEM;
455 
456 	fsl_edma->drvdata = drvdata;
457 	fsl_edma->n_chans = chans;
458 	mutex_init(&fsl_edma->fsl_edma_mutex);
459 
460 	fsl_edma->membase = devm_platform_ioremap_resource(pdev, 0);
461 	if (IS_ERR(fsl_edma->membase))
462 		return PTR_ERR(fsl_edma->membase);
463 
464 	if (!(drvdata->flags & FSL_EDMA_DRV_SPLIT_REG)) {
465 		fsl_edma_setup_regs(fsl_edma);
466 		regs = &fsl_edma->regs;
467 	}
468 
469 	if (drvdata->flags & FSL_EDMA_DRV_HAS_DMACLK) {
470 		fsl_edma->dmaclk = devm_clk_get_enabled(&pdev->dev, "dma");
471 		if (IS_ERR(fsl_edma->dmaclk)) {
472 			dev_err(&pdev->dev, "Missing DMA block clock.\n");
473 			return PTR_ERR(fsl_edma->dmaclk);
474 		}
475 	}
476 
477 	if (drvdata->flags & FSL_EDMA_DRV_HAS_CHCLK) {
478 		fsl_edma->chclk = devm_clk_get_enabled(&pdev->dev, "mp");
479 		if (IS_ERR(fsl_edma->chclk)) {
480 			dev_err(&pdev->dev, "Missing MP block clock.\n");
481 			return PTR_ERR(fsl_edma->chclk);
482 		}
483 	}
484 
485 	ret = of_property_read_variable_u32_array(np, "dma-channel-mask", chan_mask, 1, 2);
486 
487 	if (ret > 0) {
488 		fsl_edma->chan_masked = chan_mask[1];
489 		fsl_edma->chan_masked <<= 32;
490 		fsl_edma->chan_masked |= chan_mask[0];
491 	}
492 
493 	for (i = 0; i < fsl_edma->drvdata->dmamuxs; i++) {
494 		char clkname[32];
495 
496 		/* eDMAv3 mux register move to TCD area if ch_mux exist */
497 		if (drvdata->flags & FSL_EDMA_DRV_SPLIT_REG)
498 			break;
499 
500 		fsl_edma->muxbase[i] = devm_platform_ioremap_resource(pdev,
501 								      1 + i);
502 		if (IS_ERR(fsl_edma->muxbase[i])) {
503 			/* on error: disable all previously enabled clks */
504 			fsl_disable_clocks(fsl_edma, i);
505 			return PTR_ERR(fsl_edma->muxbase[i]);
506 		}
507 
508 		sprintf(clkname, "dmamux%d", i);
509 		fsl_edma->muxclk[i] = devm_clk_get_enabled(&pdev->dev, clkname);
510 		if (IS_ERR(fsl_edma->muxclk[i])) {
511 			dev_err(&pdev->dev, "Missing DMAMUX block clock.\n");
512 			/* on error: disable all previously enabled clks */
513 			return PTR_ERR(fsl_edma->muxclk[i]);
514 		}
515 	}
516 
517 	fsl_edma->big_endian = of_property_read_bool(np, "big-endian");
518 
519 	if (drvdata->flags & FSL_EDMA_DRV_HAS_PD) {
520 		ret = fsl_edma3_attach_pd(pdev, fsl_edma);
521 		if (ret)
522 			return ret;
523 	}
524 
525 	INIT_LIST_HEAD(&fsl_edma->dma_dev.channels);
526 	for (i = 0; i < fsl_edma->n_chans; i++) {
527 		struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];
528 		int len;
529 
530 		if (fsl_edma->chan_masked & BIT(i))
531 			continue;
532 
533 		snprintf(fsl_chan->chan_name, sizeof(fsl_chan->chan_name), "%s-CH%02d",
534 							   dev_name(&pdev->dev), i);
535 
536 		fsl_chan->edma = fsl_edma;
537 		fsl_chan->pm_state = RUNNING;
538 		fsl_chan->slave_id = 0;
539 		fsl_chan->idle = true;
540 		fsl_chan->dma_dir = DMA_NONE;
541 		fsl_chan->vchan.desc_free = fsl_edma_free_desc;
542 
543 		len = (drvdata->flags & FSL_EDMA_DRV_SPLIT_REG) ?
544 				offsetof(struct fsl_edma3_ch_reg, tcd) : 0;
545 		fsl_chan->tcd = fsl_edma->membase
546 				+ i * drvdata->chreg_space_sz + drvdata->chreg_off + len;
547 
548 		fsl_chan->pdev = pdev;
549 		vchan_init(&fsl_chan->vchan, &fsl_edma->dma_dev);
550 
551 		edma_write_tcdreg(fsl_chan, 0, csr);
552 		fsl_edma_chan_mux(fsl_chan, 0, false);
553 	}
554 
555 	ret = fsl_edma->drvdata->setup_irq(pdev, fsl_edma);
556 	if (ret)
557 		return ret;
558 
559 	dma_cap_set(DMA_PRIVATE, fsl_edma->dma_dev.cap_mask);
560 	dma_cap_set(DMA_SLAVE, fsl_edma->dma_dev.cap_mask);
561 	dma_cap_set(DMA_CYCLIC, fsl_edma->dma_dev.cap_mask);
562 	dma_cap_set(DMA_MEMCPY, fsl_edma->dma_dev.cap_mask);
563 
564 	fsl_edma->dma_dev.dev = &pdev->dev;
565 	fsl_edma->dma_dev.device_alloc_chan_resources
566 		= fsl_edma_alloc_chan_resources;
567 	fsl_edma->dma_dev.device_free_chan_resources
568 		= fsl_edma_free_chan_resources;
569 	fsl_edma->dma_dev.device_tx_status = fsl_edma_tx_status;
570 	fsl_edma->dma_dev.device_prep_slave_sg = fsl_edma_prep_slave_sg;
571 	fsl_edma->dma_dev.device_prep_dma_cyclic = fsl_edma_prep_dma_cyclic;
572 	fsl_edma->dma_dev.device_prep_dma_memcpy = fsl_edma_prep_memcpy;
573 	fsl_edma->dma_dev.device_config = fsl_edma_slave_config;
574 	fsl_edma->dma_dev.device_pause = fsl_edma_pause;
575 	fsl_edma->dma_dev.device_resume = fsl_edma_resume;
576 	fsl_edma->dma_dev.device_terminate_all = fsl_edma_terminate_all;
577 	fsl_edma->dma_dev.device_synchronize = fsl_edma_synchronize;
578 	fsl_edma->dma_dev.device_issue_pending = fsl_edma_issue_pending;
579 
580 	fsl_edma->dma_dev.src_addr_widths = FSL_EDMA_BUSWIDTHS;
581 	fsl_edma->dma_dev.dst_addr_widths = FSL_EDMA_BUSWIDTHS;
582 
583 	if (drvdata->flags & FSL_EDMA_DRV_BUS_8BYTE) {
584 		fsl_edma->dma_dev.src_addr_widths |= BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
585 		fsl_edma->dma_dev.dst_addr_widths |= BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
586 	}
587 
588 	fsl_edma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
589 	if (drvdata->flags & FSL_EDMA_DRV_DEV_TO_DEV)
590 		fsl_edma->dma_dev.directions |= BIT(DMA_DEV_TO_DEV);
591 
592 	fsl_edma->dma_dev.copy_align = drvdata->flags & FSL_EDMA_DRV_ALIGN_64BYTE ?
593 					DMAENGINE_ALIGN_64_BYTES :
594 					DMAENGINE_ALIGN_32_BYTES;
595 
596 	/* Per worst case 'nbytes = 1' take CITER as the max_seg_size */
597 	dma_set_max_seg_size(fsl_edma->dma_dev.dev, 0x3fff);
598 
599 	fsl_edma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
600 
601 	platform_set_drvdata(pdev, fsl_edma);
602 
603 	ret = dma_async_device_register(&fsl_edma->dma_dev);
604 	if (ret) {
605 		dev_err(&pdev->dev,
606 			"Can't register Freescale eDMA engine. (%d)\n", ret);
607 		return ret;
608 	}
609 
610 	ret = of_dma_controller_register(np,
611 			drvdata->flags & FSL_EDMA_DRV_SPLIT_REG ? fsl_edma3_xlate : fsl_edma_xlate,
612 			fsl_edma);
613 	if (ret) {
614 		dev_err(&pdev->dev,
615 			"Can't register Freescale eDMA of_dma. (%d)\n", ret);
616 		dma_async_device_unregister(&fsl_edma->dma_dev);
617 		return ret;
618 	}
619 
620 	/* enable round robin arbitration */
621 	if (!(drvdata->flags & FSL_EDMA_DRV_SPLIT_REG))
622 		edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
623 
624 	return 0;
625 }
626 
627 static int fsl_edma_remove(struct platform_device *pdev)
628 {
629 	struct device_node *np = pdev->dev.of_node;
630 	struct fsl_edma_engine *fsl_edma = platform_get_drvdata(pdev);
631 
632 	fsl_edma_irq_exit(pdev, fsl_edma);
633 	fsl_edma_cleanup_vchan(&fsl_edma->dma_dev);
634 	of_dma_controller_free(np);
635 	dma_async_device_unregister(&fsl_edma->dma_dev);
636 	fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs);
637 
638 	return 0;
639 }
640 
641 static int fsl_edma_suspend_late(struct device *dev)
642 {
643 	struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
644 	struct fsl_edma_chan *fsl_chan;
645 	unsigned long flags;
646 	int i;
647 
648 	for (i = 0; i < fsl_edma->n_chans; i++) {
649 		fsl_chan = &fsl_edma->chans[i];
650 		if (fsl_edma->chan_masked & BIT(i))
651 			continue;
652 		spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
653 		/* Make sure chan is idle or will force disable. */
654 		if (unlikely(!fsl_chan->idle)) {
655 			dev_warn(dev, "WARN: There is non-idle channel.");
656 			fsl_edma_disable_request(fsl_chan);
657 			fsl_edma_chan_mux(fsl_chan, 0, false);
658 		}
659 
660 		fsl_chan->pm_state = SUSPENDED;
661 		spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
662 	}
663 
664 	return 0;
665 }
666 
667 static int fsl_edma_resume_early(struct device *dev)
668 {
669 	struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
670 	struct fsl_edma_chan *fsl_chan;
671 	struct edma_regs *regs = &fsl_edma->regs;
672 	int i;
673 
674 	for (i = 0; i < fsl_edma->n_chans; i++) {
675 		fsl_chan = &fsl_edma->chans[i];
676 		if (fsl_edma->chan_masked & BIT(i))
677 			continue;
678 		fsl_chan->pm_state = RUNNING;
679 		edma_write_tcdreg(fsl_chan, 0, csr);
680 		if (fsl_chan->slave_id != 0)
681 			fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id, true);
682 	}
683 
684 	if (!(fsl_edma->drvdata->flags & FSL_EDMA_DRV_SPLIT_REG))
685 		edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
686 
687 	return 0;
688 }
689 
690 /*
691  * eDMA provides the service to others, so it should be suspend late
692  * and resume early. When eDMA suspend, all of the clients should stop
693  * the DMA data transmission and let the channel idle.
694  */
695 static const struct dev_pm_ops fsl_edma_pm_ops = {
696 	.suspend_late   = fsl_edma_suspend_late,
697 	.resume_early   = fsl_edma_resume_early,
698 };
699 
700 static struct platform_driver fsl_edma_driver = {
701 	.driver		= {
702 		.name	= "fsl-edma",
703 		.of_match_table = fsl_edma_dt_ids,
704 		.pm     = &fsl_edma_pm_ops,
705 	},
706 	.probe          = fsl_edma_probe,
707 	.remove		= fsl_edma_remove,
708 };
709 
710 static int __init fsl_edma_init(void)
711 {
712 	return platform_driver_register(&fsl_edma_driver);
713 }
714 subsys_initcall(fsl_edma_init);
715 
716 static void __exit fsl_edma_exit(void)
717 {
718 	platform_driver_unregister(&fsl_edma_driver);
719 }
720 module_exit(fsl_edma_exit);
721 
722 MODULE_ALIAS("platform:fsl-edma");
723 MODULE_DESCRIPTION("Freescale eDMA engine driver");
724 MODULE_LICENSE("GPL v2");
725