xref: /openbmc/linux/sound/soc/sh/rcar/dma.c (revision 4bce6fce)
1 /*
2  * Renesas R-Car Audio DMAC support
3  *
4  * Copyright (C) 2015 Renesas Electronics Corp.
5  * Copyright (c) 2015 Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/delay.h>
12 #include <linux/of_dma.h>
13 #include "rsnd.h"
14 
15 /*
16  * Audio DMAC peri peri register
17  */
18 #define PDMASAR		0x00
19 #define PDMADAR		0x04
20 #define PDMACHCR	0x0c
21 
22 /* PDMACHCR */
23 #define PDMACHCR_DE		(1 << 0)
24 
25 struct rsnd_dma_ctrl {
26 	void __iomem *base;
27 	int dmapp_num;
28 };
29 
30 #define rsnd_priv_to_dmac(p)	((struct rsnd_dma_ctrl *)(p)->dma)
31 
32 /*
33  *		Audio DMAC
34  */
35 static void rsnd_dmaen_complete(void *data)
36 {
37 	struct rsnd_dma *dma = (struct rsnd_dma *)data;
38 	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
39 	struct rsnd_dai_stream *io = rsnd_mod_to_io(mod);
40 
41 	/*
42 	 * Renesas sound Gen1 needs 1 DMAC,
43 	 * Gen2 needs 2 DMAC.
44 	 * In Gen2 case, it are Audio-DMAC, and Audio-DMAC-peri-peri.
45 	 * But, Audio-DMAC-peri-peri doesn't have interrupt,
46 	 * and this driver is assuming that here.
47 	 *
48 	 * If Audio-DMAC-peri-peri has interrpt,
49 	 * rsnd_dai_pointer_update() will be called twice,
50 	 * ant it will breaks io->byte_pos
51 	 */
52 
53 	rsnd_dai_pointer_update(io, io->byte_per_period);
54 }
55 
56 static void rsnd_dmaen_stop(struct rsnd_dma *dma)
57 {
58 	struct rsnd_dmaen *dmaen = rsnd_dma_to_dmaen(dma);
59 
60 	dmaengine_terminate_all(dmaen->chan);
61 }
62 
63 static void rsnd_dmaen_start(struct rsnd_dma *dma)
64 {
65 	struct rsnd_dmaen *dmaen = rsnd_dma_to_dmaen(dma);
66 	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
67 	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
68 	struct rsnd_dai_stream *io = rsnd_mod_to_io(mod);
69 	struct snd_pcm_substream *substream = io->substream;
70 	struct device *dev = rsnd_priv_to_dev(priv);
71 	struct dma_async_tx_descriptor *desc;
72 	int is_play = rsnd_io_is_play(io);
73 
74 	desc = dmaengine_prep_dma_cyclic(dmaen->chan,
75 					 substream->runtime->dma_addr,
76 					 snd_pcm_lib_buffer_bytes(substream),
77 					 snd_pcm_lib_period_bytes(substream),
78 					 is_play ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
79 					 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
80 
81 	if (!desc) {
82 		dev_err(dev, "dmaengine_prep_slave_sg() fail\n");
83 		return;
84 	}
85 
86 	desc->callback		= rsnd_dmaen_complete;
87 	desc->callback_param	= dma;
88 
89 	if (dmaengine_submit(desc) < 0) {
90 		dev_err(dev, "dmaengine_submit() fail\n");
91 		return;
92 	}
93 
94 	dma_async_issue_pending(dmaen->chan);
95 }
96 
97 struct dma_chan *rsnd_dma_request_channel(struct device_node *of_node,
98 					  struct rsnd_mod *mod, char *name)
99 {
100 	struct dma_chan *chan;
101 	struct device_node *np;
102 	int i = 0;
103 
104 	for_each_child_of_node(of_node, np) {
105 		if (i == rsnd_mod_id(mod))
106 			break;
107 		i++;
108 	}
109 
110 	chan = of_dma_request_slave_channel(np, name);
111 
112 	of_node_put(np);
113 	of_node_put(of_node);
114 
115 	return chan;
116 }
117 
118 static struct dma_chan *rsnd_dmaen_request_channel(struct rsnd_mod *mod_from,
119 						   struct rsnd_mod *mod_to)
120 {
121 	if ((!mod_from && !mod_to) ||
122 	    (mod_from && mod_to))
123 		return NULL;
124 
125 	if (mod_from)
126 		return rsnd_mod_dma_req(mod_from);
127 	else
128 		return rsnd_mod_dma_req(mod_to);
129 }
130 
131 static int rsnd_dmaen_init(struct rsnd_priv *priv, struct rsnd_dma *dma, int id,
132 			   struct rsnd_mod *mod_from, struct rsnd_mod *mod_to)
133 {
134 	struct rsnd_dmaen *dmaen = rsnd_dma_to_dmaen(dma);
135 	struct device *dev = rsnd_priv_to_dev(priv);
136 	struct dma_slave_config cfg = {};
137 	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
138 	struct rsnd_dai_stream *io = rsnd_mod_to_io(mod);
139 	int is_play = rsnd_io_is_play(io);
140 	int ret;
141 
142 	if (dmaen->chan) {
143 		dev_err(dev, "it already has dma channel\n");
144 		return -EIO;
145 	}
146 
147 	if (dev->of_node) {
148 		dmaen->chan = rsnd_dmaen_request_channel(mod_from, mod_to);
149 	} else {
150 		dma_cap_mask_t mask;
151 
152 		dma_cap_zero(mask);
153 		dma_cap_set(DMA_SLAVE, mask);
154 
155 		dmaen->chan = dma_request_channel(mask, shdma_chan_filter,
156 						  (void *)id);
157 	}
158 	if (IS_ERR_OR_NULL(dmaen->chan)) {
159 		dev_err(dev, "can't get dma channel\n");
160 		goto rsnd_dma_channel_err;
161 	}
162 
163 	cfg.direction	= is_play ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
164 	cfg.src_addr	= dma->src_addr;
165 	cfg.dst_addr	= dma->dst_addr;
166 	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
167 	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
168 
169 	dev_dbg(dev, "dma : %pad -> %pad\n",
170 		&cfg.src_addr, &cfg.dst_addr);
171 
172 	ret = dmaengine_slave_config(dmaen->chan, &cfg);
173 	if (ret < 0)
174 		goto rsnd_dma_init_err;
175 
176 	return 0;
177 
178 rsnd_dma_init_err:
179 	rsnd_dma_quit(dma);
180 rsnd_dma_channel_err:
181 
182 	/*
183 	 * DMA failed. try to PIO mode
184 	 * see
185 	 *	rsnd_ssi_fallback()
186 	 *	rsnd_rdai_continuance_probe()
187 	 */
188 	return -EAGAIN;
189 }
190 
191 static void rsnd_dmaen_quit(struct rsnd_dma *dma)
192 {
193 	struct rsnd_dmaen *dmaen = rsnd_dma_to_dmaen(dma);
194 
195 	if (dmaen->chan)
196 		dma_release_channel(dmaen->chan);
197 
198 	dmaen->chan = NULL;
199 }
200 
201 static struct rsnd_dma_ops rsnd_dmaen_ops = {
202 	.start	= rsnd_dmaen_start,
203 	.stop	= rsnd_dmaen_stop,
204 	.init	= rsnd_dmaen_init,
205 	.quit	= rsnd_dmaen_quit,
206 };
207 
208 /*
209  *		Audio DMAC peri peri
210  */
211 static const u8 gen2_id_table_ssiu[] = {
212 	0x00, /* SSI00 */
213 	0x04, /* SSI10 */
214 	0x08, /* SSI20 */
215 	0x0c, /* SSI3  */
216 	0x0d, /* SSI4  */
217 	0x0e, /* SSI5  */
218 	0x0f, /* SSI6  */
219 	0x10, /* SSI7  */
220 	0x11, /* SSI8  */
221 	0x12, /* SSI90 */
222 };
223 static const u8 gen2_id_table_scu[] = {
224 	0x2d, /* SCU_SRCI0 */
225 	0x2e, /* SCU_SRCI1 */
226 	0x2f, /* SCU_SRCI2 */
227 	0x30, /* SCU_SRCI3 */
228 	0x31, /* SCU_SRCI4 */
229 	0x32, /* SCU_SRCI5 */
230 	0x33, /* SCU_SRCI6 */
231 	0x34, /* SCU_SRCI7 */
232 	0x35, /* SCU_SRCI8 */
233 	0x36, /* SCU_SRCI9 */
234 };
235 static const u8 gen2_id_table_cmd[] = {
236 	0x37, /* SCU_CMD0 */
237 	0x38, /* SCU_CMD1 */
238 };
239 
240 static u32 rsnd_dmapp_get_id(struct rsnd_mod *mod)
241 {
242 	struct rsnd_dai_stream *io = rsnd_mod_to_io(mod);
243 	struct rsnd_mod *ssi = rsnd_io_to_mod_ssi(io);
244 	struct rsnd_mod *src = rsnd_io_to_mod_src(io);
245 	struct rsnd_mod *dvc = rsnd_io_to_mod_dvc(io);
246 	const u8 *entry = NULL;
247 	int id = rsnd_mod_id(mod);
248 	int size = 0;
249 
250 	if (mod == ssi) {
251 		entry = gen2_id_table_ssiu;
252 		size = ARRAY_SIZE(gen2_id_table_ssiu);
253 	} else if (mod == src) {
254 		entry = gen2_id_table_scu;
255 		size = ARRAY_SIZE(gen2_id_table_scu);
256 	} else if (mod == dvc) {
257 		entry = gen2_id_table_cmd;
258 		size = ARRAY_SIZE(gen2_id_table_cmd);
259 	}
260 
261 	if (!entry)
262 		return 0xFF;
263 
264 	if (size <= id)
265 		return 0xFF;
266 
267 	return entry[id];
268 }
269 
270 static u32 rsnd_dmapp_get_chcr(struct rsnd_mod *mod_from,
271 			       struct rsnd_mod *mod_to)
272 {
273 	return	(rsnd_dmapp_get_id(mod_from) << 24) +
274 		(rsnd_dmapp_get_id(mod_to) << 16);
275 }
276 
277 #define rsnd_dmapp_addr(dmac, dma, reg) \
278 	(dmac->base + 0x20 + reg + \
279 	 (0x10 * rsnd_dma_to_dmapp(dma)->dmapp_id))
280 static void rsnd_dmapp_write(struct rsnd_dma *dma, u32 data, u32 reg)
281 {
282 	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
283 	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
284 	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
285 	struct device *dev = rsnd_priv_to_dev(priv);
286 
287 	dev_dbg(dev, "w %p : %08x\n", rsnd_dmapp_addr(dmac, dma, reg), data);
288 
289 	iowrite32(data, rsnd_dmapp_addr(dmac, dma, reg));
290 }
291 
292 static u32 rsnd_dmapp_read(struct rsnd_dma *dma, u32 reg)
293 {
294 	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
295 	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
296 	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
297 
298 	return ioread32(rsnd_dmapp_addr(dmac, dma, reg));
299 }
300 
301 static void rsnd_dmapp_stop(struct rsnd_dma *dma)
302 {
303 	int i;
304 
305 	rsnd_dmapp_write(dma, 0, PDMACHCR);
306 
307 	for (i = 0; i < 1024; i++) {
308 		if (0 == rsnd_dmapp_read(dma, PDMACHCR))
309 			return;
310 		udelay(1);
311 	}
312 }
313 
314 static void rsnd_dmapp_start(struct rsnd_dma *dma)
315 {
316 	struct rsnd_dmapp *dmapp = rsnd_dma_to_dmapp(dma);
317 
318 	rsnd_dmapp_write(dma, dma->src_addr,	PDMASAR);
319 	rsnd_dmapp_write(dma, dma->dst_addr,	PDMADAR);
320 	rsnd_dmapp_write(dma, dmapp->chcr,	PDMACHCR);
321 }
322 
323 static int rsnd_dmapp_init(struct rsnd_priv *priv, struct rsnd_dma *dma, int id,
324 			   struct rsnd_mod *mod_from, struct rsnd_mod *mod_to)
325 {
326 	struct rsnd_dmapp *dmapp = rsnd_dma_to_dmapp(dma);
327 	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
328 	struct device *dev = rsnd_priv_to_dev(priv);
329 
330 	dmapp->dmapp_id = dmac->dmapp_num;
331 	dmapp->chcr = rsnd_dmapp_get_chcr(mod_from, mod_to) | PDMACHCR_DE;
332 
333 	dmac->dmapp_num++;
334 
335 	rsnd_dmapp_stop(dma);
336 
337 	dev_dbg(dev, "id/src/dst/chcr = %d/%pad/%pad/%08x\n",
338 		dmapp->dmapp_id, &dma->src_addr, &dma->dst_addr, dmapp->chcr);
339 
340 	return 0;
341 }
342 
343 static struct rsnd_dma_ops rsnd_dmapp_ops = {
344 	.start	= rsnd_dmapp_start,
345 	.stop	= rsnd_dmapp_stop,
346 	.init	= rsnd_dmapp_init,
347 	.quit	= rsnd_dmapp_stop,
348 };
349 
350 /*
351  *		Common DMAC Interface
352  */
353 
354 /*
355  *	DMA read/write register offset
356  *
357  *	RSND_xxx_I_N	for Audio DMAC input
358  *	RSND_xxx_O_N	for Audio DMAC output
359  *	RSND_xxx_I_P	for Audio DMAC peri peri input
360  *	RSND_xxx_O_P	for Audio DMAC peri peri output
361  *
362  *	ex) R-Car H2 case
363  *	      mod        / DMAC in    / DMAC out   / DMAC PP in / DMAC pp out
364  *	SSI : 0xec541000 / 0xec241008 / 0xec24100c
365  *	SSIU: 0xec541000 / 0xec100000 / 0xec100000 / 0xec400000 / 0xec400000
366  *	SCU : 0xec500000 / 0xec000000 / 0xec004000 / 0xec300000 / 0xec304000
367  *	CMD : 0xec500000 /            / 0xec008000                0xec308000
368  */
369 #define RDMA_SSI_I_N(addr, i)	(addr ##_reg - 0x00300000 + (0x40 * i) + 0x8)
370 #define RDMA_SSI_O_N(addr, i)	(addr ##_reg - 0x00300000 + (0x40 * i) + 0xc)
371 
372 #define RDMA_SSIU_I_N(addr, i)	(addr ##_reg - 0x00441000 + (0x1000 * i))
373 #define RDMA_SSIU_O_N(addr, i)	(addr ##_reg - 0x00441000 + (0x1000 * i))
374 
375 #define RDMA_SSIU_I_P(addr, i)	(addr ##_reg - 0x00141000 + (0x1000 * i))
376 #define RDMA_SSIU_O_P(addr, i)	(addr ##_reg - 0x00141000 + (0x1000 * i))
377 
378 #define RDMA_SRC_I_N(addr, i)	(addr ##_reg - 0x00500000 + (0x400 * i))
379 #define RDMA_SRC_O_N(addr, i)	(addr ##_reg - 0x004fc000 + (0x400 * i))
380 
381 #define RDMA_SRC_I_P(addr, i)	(addr ##_reg - 0x00200000 + (0x400 * i))
382 #define RDMA_SRC_O_P(addr, i)	(addr ##_reg - 0x001fc000 + (0x400 * i))
383 
384 #define RDMA_CMD_O_N(addr, i)	(addr ##_reg - 0x004f8000 + (0x400 * i))
385 #define RDMA_CMD_O_P(addr, i)	(addr ##_reg - 0x001f8000 + (0x400 * i))
386 
387 static dma_addr_t
388 rsnd_gen2_dma_addr(struct rsnd_priv *priv,
389 		   struct rsnd_mod *mod,
390 		   int is_play, int is_from)
391 {
392 	struct device *dev = rsnd_priv_to_dev(priv);
393 	struct rsnd_dai_stream *io = rsnd_mod_to_io(mod);
394 	phys_addr_t ssi_reg = rsnd_gen_get_phy_addr(priv, RSND_GEN2_SSI);
395 	phys_addr_t src_reg = rsnd_gen_get_phy_addr(priv, RSND_GEN2_SCU);
396 	int is_ssi = !!(rsnd_io_to_mod_ssi(io) == mod);
397 	int use_src = !!rsnd_io_to_mod_src(io);
398 	int use_dvc = !!rsnd_io_to_mod_dvc(io);
399 	int id = rsnd_mod_id(mod);
400 	struct dma_addr {
401 		dma_addr_t out_addr;
402 		dma_addr_t in_addr;
403 	} dma_addrs[3][2][3] = {
404 		/* SRC */
405 		{{{ 0,				0 },
406 		  /* Capture */
407 		  { RDMA_SRC_O_N(src, id),	RDMA_SRC_I_P(src, id) },
408 		  { RDMA_CMD_O_N(src, id),	RDMA_SRC_I_P(src, id) } },
409 		 /* Playback */
410 		 {{ 0,				0, },
411 		  { RDMA_SRC_O_P(src, id),	RDMA_SRC_I_N(src, id) },
412 		  { RDMA_CMD_O_P(src, id),	RDMA_SRC_I_N(src, id) } }
413 		},
414 		/* SSI */
415 		/* Capture */
416 		{{{ RDMA_SSI_O_N(ssi, id),	0 },
417 		  { RDMA_SSIU_O_P(ssi, id),	0 },
418 		  { RDMA_SSIU_O_P(ssi, id),	0 } },
419 		 /* Playback */
420 		 {{ 0,				RDMA_SSI_I_N(ssi, id) },
421 		  { 0,				RDMA_SSIU_I_P(ssi, id) },
422 		  { 0,				RDMA_SSIU_I_P(ssi, id) } }
423 		},
424 		/* SSIU */
425 		/* Capture */
426 		{{{ RDMA_SSIU_O_N(ssi, id),	0 },
427 		  { RDMA_SSIU_O_P(ssi, id),	0 },
428 		  { RDMA_SSIU_O_P(ssi, id),	0 } },
429 		 /* Playback */
430 		 {{ 0,				RDMA_SSIU_I_N(ssi, id) },
431 		  { 0,				RDMA_SSIU_I_P(ssi, id) },
432 		  { 0,				RDMA_SSIU_I_P(ssi, id) } } },
433 	};
434 
435 	/* it shouldn't happen */
436 	if (use_dvc && !use_src)
437 		dev_err(dev, "DVC is selected without SRC\n");
438 
439 	/* use SSIU or SSI ? */
440 	if (is_ssi && rsnd_ssi_use_busif(mod))
441 		is_ssi++;
442 
443 	return (is_from) ?
444 		dma_addrs[is_ssi][is_play][use_src + use_dvc].out_addr :
445 		dma_addrs[is_ssi][is_play][use_src + use_dvc].in_addr;
446 }
447 
448 static dma_addr_t rsnd_dma_addr(struct rsnd_priv *priv,
449 				struct rsnd_mod *mod,
450 				int is_play, int is_from)
451 {
452 	/*
453 	 * gen1 uses default DMA addr
454 	 */
455 	if (rsnd_is_gen1(priv))
456 		return 0;
457 
458 	if (!mod)
459 		return 0;
460 
461 	return rsnd_gen2_dma_addr(priv, mod, is_play, is_from);
462 }
463 
464 #define MOD_MAX 4 /* MEM/SSI/SRC/DVC */
465 static void rsnd_dma_of_path(struct rsnd_dma *dma,
466 			     int is_play,
467 			     struct rsnd_mod **mod_from,
468 			     struct rsnd_mod **mod_to)
469 {
470 	struct rsnd_mod *this = rsnd_dma_to_mod(dma);
471 	struct rsnd_dai_stream *io = rsnd_mod_to_io(this);
472 	struct rsnd_mod *ssi = rsnd_io_to_mod_ssi(io);
473 	struct rsnd_mod *src = rsnd_io_to_mod_src(io);
474 	struct rsnd_mod *dvc = rsnd_io_to_mod_dvc(io);
475 	struct rsnd_mod *mod[MOD_MAX];
476 	int i, index;
477 
478 
479 	for (i = 0; i < MOD_MAX; i++)
480 		mod[i] = NULL;
481 
482 	/*
483 	 * in play case...
484 	 *
485 	 * src -> dst
486 	 *
487 	 * mem -> SSI
488 	 * mem -> SRC -> SSI
489 	 * mem -> SRC -> DVC -> SSI
490 	 */
491 	mod[0] = NULL; /* for "mem" */
492 	index = 1;
493 	for (i = 1; i < MOD_MAX; i++) {
494 		if (!src) {
495 			mod[i] = ssi;
496 		} else if (!dvc) {
497 			mod[i] = src;
498 			src = NULL;
499 		} else {
500 			if ((!is_play) && (this == src))
501 				this = dvc;
502 
503 			mod[i] = (is_play) ? src : dvc;
504 			i++;
505 			mod[i] = (is_play) ? dvc : src;
506 			src = NULL;
507 			dvc = NULL;
508 		}
509 
510 		if (mod[i] == this)
511 			index = i;
512 
513 		if (mod[i] == ssi)
514 			break;
515 	}
516 
517 	if (is_play) {
518 		*mod_from = mod[index - 1];
519 		*mod_to   = mod[index];
520 	} else {
521 		*mod_from = mod[index];
522 		*mod_to   = mod[index - 1];
523 	}
524 }
525 
526 void rsnd_dma_stop(struct rsnd_dma *dma)
527 {
528 	dma->ops->stop(dma);
529 }
530 
531 void rsnd_dma_start(struct rsnd_dma *dma)
532 {
533 	dma->ops->start(dma);
534 }
535 
536 void rsnd_dma_quit(struct rsnd_dma *dma)
537 {
538 	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
539 	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
540 	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
541 
542 	if (!dmac)
543 		return;
544 
545 	dma->ops->quit(dma);
546 }
547 
548 int rsnd_dma_init(struct rsnd_priv *priv, struct rsnd_dma *dma, int id)
549 {
550 	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
551 	struct rsnd_mod *mod_from;
552 	struct rsnd_mod *mod_to;
553 	struct rsnd_dai_stream *io = rsnd_mod_to_io(mod);
554 	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
555 	int is_play = rsnd_io_is_play(io);
556 
557 	/*
558 	 * DMA failed. try to PIO mode
559 	 * see
560 	 *	rsnd_ssi_fallback()
561 	 *	rsnd_rdai_continuance_probe()
562 	 */
563 	if (!dmac)
564 		return -EAGAIN;
565 
566 	rsnd_dma_of_path(dma, is_play, &mod_from, &mod_to);
567 
568 	dma->src_addr = rsnd_dma_addr(priv, mod_from, is_play, 1);
569 	dma->dst_addr = rsnd_dma_addr(priv, mod_to,   is_play, 0);
570 
571 	/* for Gen2 */
572 	if (mod_from && mod_to)
573 		dma->ops = &rsnd_dmapp_ops;
574 	else
575 		dma->ops = &rsnd_dmaen_ops;
576 
577 	/* for Gen1, overwrite */
578 	if (rsnd_is_gen1(priv))
579 		dma->ops = &rsnd_dmaen_ops;
580 
581 	return dma->ops->init(priv, dma, id, mod_from, mod_to);
582 }
583 
584 int rsnd_dma_probe(struct platform_device *pdev,
585 		   const struct rsnd_of_data *of_data,
586 		   struct rsnd_priv *priv)
587 {
588 	struct device *dev = rsnd_priv_to_dev(priv);
589 	struct rsnd_dma_ctrl *dmac;
590 	struct resource *res;
591 
592 	/*
593 	 * for Gen1
594 	 */
595 	if (rsnd_is_gen1(priv))
596 		return 0;
597 
598 	/*
599 	 * for Gen2
600 	 */
601 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "audmapp");
602 	dmac = devm_kzalloc(dev, sizeof(*dmac), GFP_KERNEL);
603 	if (!dmac || !res) {
604 		dev_err(dev, "dma allocate failed\n");
605 		return 0; /* it will be PIO mode */
606 	}
607 
608 	dmac->dmapp_num = 0;
609 	dmac->base = devm_ioremap_resource(dev, res);
610 	if (IS_ERR(dmac->base))
611 		return PTR_ERR(dmac->base);
612 
613 	priv->dma = dmac;
614 
615 	return 0;
616 }
617