xref: /openbmc/linux/sound/soc/stm/stm32_spdifrx.c (revision 612a462a)
1 /*
2  * STM32 ALSA SoC Digital Audio Interface (SPDIF-rx) driver.
3  *
4  * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
5  * Author(s): Olivier Moysan <olivier.moysan@st.com> for STMicroelectronics.
6  *
7  * License terms: GPL V2.0.
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License version 2 as published by
11  * the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
15  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
16  * details.
17  */
18 
19 #include <linux/clk.h>
20 #include <linux/completion.h>
21 #include <linux/delay.h>
22 #include <linux/module.h>
23 #include <linux/of_platform.h>
24 #include <linux/regmap.h>
25 #include <linux/reset.h>
26 
27 #include <sound/dmaengine_pcm.h>
28 #include <sound/pcm_params.h>
29 
30 /* SPDIF-rx Register Map */
31 #define STM32_SPDIFRX_CR	0x00
32 #define STM32_SPDIFRX_IMR	0x04
33 #define STM32_SPDIFRX_SR	0x08
34 #define STM32_SPDIFRX_IFCR	0x0C
35 #define STM32_SPDIFRX_DR	0x10
36 #define STM32_SPDIFRX_CSR	0x14
37 #define STM32_SPDIFRX_DIR	0x18
38 
39 /* Bit definition for SPDIF_CR register */
40 #define SPDIFRX_CR_SPDIFEN_SHIFT	0
41 #define SPDIFRX_CR_SPDIFEN_MASK	GENMASK(1, SPDIFRX_CR_SPDIFEN_SHIFT)
42 #define SPDIFRX_CR_SPDIFENSET(x)	((x) << SPDIFRX_CR_SPDIFEN_SHIFT)
43 
44 #define SPDIFRX_CR_RXDMAEN	BIT(2)
45 #define SPDIFRX_CR_RXSTEO	BIT(3)
46 
47 #define SPDIFRX_CR_DRFMT_SHIFT	4
48 #define SPDIFRX_CR_DRFMT_MASK	GENMASK(5, SPDIFRX_CR_DRFMT_SHIFT)
49 #define SPDIFRX_CR_DRFMTSET(x)	((x) << SPDIFRX_CR_DRFMT_SHIFT)
50 
51 #define SPDIFRX_CR_PMSK		BIT(6)
52 #define SPDIFRX_CR_VMSK		BIT(7)
53 #define SPDIFRX_CR_CUMSK	BIT(8)
54 #define SPDIFRX_CR_PTMSK	BIT(9)
55 #define SPDIFRX_CR_CBDMAEN	BIT(10)
56 #define SPDIFRX_CR_CHSEL_SHIFT	11
57 #define SPDIFRX_CR_CHSEL	BIT(SPDIFRX_CR_CHSEL_SHIFT)
58 
59 #define SPDIFRX_CR_NBTR_SHIFT	12
60 #define SPDIFRX_CR_NBTR_MASK	GENMASK(13, SPDIFRX_CR_NBTR_SHIFT)
61 #define SPDIFRX_CR_NBTRSET(x)	((x) << SPDIFRX_CR_NBTR_SHIFT)
62 
63 #define SPDIFRX_CR_WFA		BIT(14)
64 
65 #define SPDIFRX_CR_INSEL_SHIFT	16
66 #define SPDIFRX_CR_INSEL_MASK	GENMASK(18, PDIFRX_CR_INSEL_SHIFT)
67 #define SPDIFRX_CR_INSELSET(x)	((x) << SPDIFRX_CR_INSEL_SHIFT)
68 
69 #define SPDIFRX_CR_CKSEN_SHIFT	20
70 #define SPDIFRX_CR_CKSEN	BIT(20)
71 #define SPDIFRX_CR_CKSBKPEN	BIT(21)
72 
73 /* Bit definition for SPDIFRX_IMR register */
74 #define SPDIFRX_IMR_RXNEI	BIT(0)
75 #define SPDIFRX_IMR_CSRNEIE	BIT(1)
76 #define SPDIFRX_IMR_PERRIE	BIT(2)
77 #define SPDIFRX_IMR_OVRIE	BIT(3)
78 #define SPDIFRX_IMR_SBLKIE	BIT(4)
79 #define SPDIFRX_IMR_SYNCDIE	BIT(5)
80 #define SPDIFRX_IMR_IFEIE	BIT(6)
81 
82 #define SPDIFRX_XIMR_MASK	GENMASK(6, 0)
83 
84 /* Bit definition for SPDIFRX_SR register */
85 #define SPDIFRX_SR_RXNE		BIT(0)
86 #define SPDIFRX_SR_CSRNE	BIT(1)
87 #define SPDIFRX_SR_PERR		BIT(2)
88 #define SPDIFRX_SR_OVR		BIT(3)
89 #define SPDIFRX_SR_SBD		BIT(4)
90 #define SPDIFRX_SR_SYNCD	BIT(5)
91 #define SPDIFRX_SR_FERR		BIT(6)
92 #define SPDIFRX_SR_SERR		BIT(7)
93 #define SPDIFRX_SR_TERR		BIT(8)
94 
95 #define SPDIFRX_SR_WIDTH5_SHIFT	16
96 #define SPDIFRX_SR_WIDTH5_MASK	GENMASK(30, PDIFRX_SR_WIDTH5_SHIFT)
97 #define SPDIFRX_SR_WIDTH5SET(x)	((x) << SPDIFRX_SR_WIDTH5_SHIFT)
98 
99 /* Bit definition for SPDIFRX_IFCR register */
100 #define SPDIFRX_IFCR_PERRCF	BIT(2)
101 #define SPDIFRX_IFCR_OVRCF	BIT(3)
102 #define SPDIFRX_IFCR_SBDCF	BIT(4)
103 #define SPDIFRX_IFCR_SYNCDCF	BIT(5)
104 
105 #define SPDIFRX_XIFCR_MASK	GENMASK(5, 2)
106 
107 /* Bit definition for SPDIFRX_DR register (DRFMT = 0b00) */
108 #define SPDIFRX_DR0_DR_SHIFT	0
109 #define SPDIFRX_DR0_DR_MASK	GENMASK(23, SPDIFRX_DR0_DR_SHIFT)
110 #define SPDIFRX_DR0_DRSET(x)	((x) << SPDIFRX_DR0_DR_SHIFT)
111 
112 #define SPDIFRX_DR0_PE		BIT(24)
113 
114 #define SPDIFRX_DR0_V		BIT(25)
115 #define SPDIFRX_DR0_U		BIT(26)
116 #define SPDIFRX_DR0_C		BIT(27)
117 
118 #define SPDIFRX_DR0_PT_SHIFT	28
119 #define SPDIFRX_DR0_PT_MASK	GENMASK(29, SPDIFRX_DR0_PT_SHIFT)
120 #define SPDIFRX_DR0_PTSET(x)	((x) << SPDIFRX_DR0_PT_SHIFT)
121 
122 /* Bit definition for SPDIFRX_DR register (DRFMT = 0b01) */
123 #define  SPDIFRX_DR1_PE		BIT(0)
124 #define  SPDIFRX_DR1_V		BIT(1)
125 #define  SPDIFRX_DR1_U		BIT(2)
126 #define  SPDIFRX_DR1_C		BIT(3)
127 
128 #define  SPDIFRX_DR1_PT_SHIFT	4
129 #define  SPDIFRX_DR1_PT_MASK	GENMASK(5, SPDIFRX_DR1_PT_SHIFT)
130 #define  SPDIFRX_DR1_PTSET(x)	((x) << SPDIFRX_DR1_PT_SHIFT)
131 
132 #define SPDIFRX_DR1_DR_SHIFT	8
133 #define SPDIFRX_DR1_DR_MASK	GENMASK(31, SPDIFRX_DR1_DR_SHIFT)
134 #define SPDIFRX_DR1_DRSET(x)	((x) << SPDIFRX_DR1_DR_SHIFT)
135 
136 /* Bit definition for SPDIFRX_DR register (DRFMT = 0b10) */
137 #define SPDIFRX_DR1_DRNL1_SHIFT	0
138 #define SPDIFRX_DR1_DRNL1_MASK	GENMASK(15, SPDIFRX_DR1_DRNL1_SHIFT)
139 #define SPDIFRX_DR1_DRNL1SET(x)	((x) << SPDIFRX_DR1_DRNL1_SHIFT)
140 
141 #define SPDIFRX_DR1_DRNL2_SHIFT	16
142 #define SPDIFRX_DR1_DRNL2_MASK	GENMASK(31, SPDIFRX_DR1_DRNL2_SHIFT)
143 #define SPDIFRX_DR1_DRNL2SET(x)	((x) << SPDIFRX_DR1_DRNL2_SHIFT)
144 
145 /* Bit definition for SPDIFRX_CSR register */
146 #define SPDIFRX_CSR_USR_SHIFT	0
147 #define SPDIFRX_CSR_USR_MASK	GENMASK(15, SPDIFRX_CSR_USR_SHIFT)
148 #define SPDIFRX_CSR_USRGET(x)	(((x) & SPDIFRX_CSR_USR_MASK)\
149 				>> SPDIFRX_CSR_USR_SHIFT)
150 
151 #define SPDIFRX_CSR_CS_SHIFT	16
152 #define SPDIFRX_CSR_CS_MASK	GENMASK(23, SPDIFRX_CSR_CS_SHIFT)
153 #define SPDIFRX_CSR_CSGET(x)	(((x) & SPDIFRX_CSR_CS_MASK)\
154 				>> SPDIFRX_CSR_CS_SHIFT)
155 
156 #define SPDIFRX_CSR_SOB		BIT(24)
157 
158 /* Bit definition for SPDIFRX_DIR register */
159 #define SPDIFRX_DIR_THI_SHIFT	0
160 #define SPDIFRX_DIR_THI_MASK	GENMASK(12, SPDIFRX_DIR_THI_SHIFT)
161 #define SPDIFRX_DIR_THI_SET(x)	((x) << SPDIFRX_DIR_THI_SHIFT)
162 
163 #define SPDIFRX_DIR_TLO_SHIFT	16
164 #define SPDIFRX_DIR_TLO_MASK	GENMASK(28, SPDIFRX_DIR_TLO_SHIFT)
165 #define SPDIFRX_DIR_TLO_SET(x)	((x) << SPDIFRX_DIR_TLO_SHIFT)
166 
167 #define SPDIFRX_SPDIFEN_DISABLE	0x0
168 #define SPDIFRX_SPDIFEN_SYNC	0x1
169 #define SPDIFRX_SPDIFEN_ENABLE	0x3
170 
171 #define SPDIFRX_IN1		0x1
172 #define SPDIFRX_IN2		0x2
173 #define SPDIFRX_IN3		0x3
174 #define SPDIFRX_IN4		0x4
175 #define SPDIFRX_IN5		0x5
176 #define SPDIFRX_IN6		0x6
177 #define SPDIFRX_IN7		0x7
178 #define SPDIFRX_IN8		0x8
179 
180 #define SPDIFRX_NBTR_NONE	0x0
181 #define SPDIFRX_NBTR_3		0x1
182 #define SPDIFRX_NBTR_15		0x2
183 #define SPDIFRX_NBTR_63		0x3
184 
185 #define SPDIFRX_DRFMT_RIGHT	0x0
186 #define SPDIFRX_DRFMT_LEFT	0x1
187 #define SPDIFRX_DRFMT_PACKED	0x2
188 
189 /* 192 CS bits in S/PDIF frame. i.e 24 CS bytes */
190 #define SPDIFRX_CS_BYTES_NB	24
191 #define SPDIFRX_UB_BYTES_NB	48
192 
193 /*
194  * CSR register is retrieved as a 32 bits word
195  * It contains 1 channel status byte and 2 user data bytes
196  * 2 S/PDIF frames are acquired to get all CS/UB bits
197  */
198 #define SPDIFRX_CSR_BUF_LENGTH	(SPDIFRX_CS_BYTES_NB * 4 * 2)
199 
200 /**
201  * struct stm32_spdifrx_data - private data of SPDIFRX
202  * @pdev: device data pointer
203  * @base: mmio register base virtual address
204  * @regmap: SPDIFRX register map pointer
205  * @regmap_conf: SPDIFRX register map configuration pointer
206  * @cs_completion: channel status retrieving completion
207  * @kclk: kernel clock feeding the SPDIFRX clock generator
208  * @dma_params: dma configuration data for rx channel
209  * @substream: PCM substream data pointer
210  * @dmab: dma buffer info pointer
211  * @ctrl_chan: dma channel for S/PDIF control bits
212  * @desc:dma async transaction descriptor
213  * @slave_config: dma slave channel runtime config pointer
214  * @phys_addr: SPDIFRX registers physical base address
215  * @lock: synchronization enabling lock
216  * @cs: channel status buffer
217  * @ub: user data buffer
218  * @irq: SPDIFRX interrupt line
219  * @refcount: keep count of opened DMA channels
220  */
221 struct stm32_spdifrx_data {
222 	struct platform_device *pdev;
223 	void __iomem *base;
224 	struct regmap *regmap;
225 	const struct regmap_config *regmap_conf;
226 	struct completion cs_completion;
227 	struct clk *kclk;
228 	struct snd_dmaengine_dai_dma_data dma_params;
229 	struct snd_pcm_substream *substream;
230 	struct snd_dma_buffer *dmab;
231 	struct dma_chan *ctrl_chan;
232 	struct dma_async_tx_descriptor *desc;
233 	struct dma_slave_config slave_config;
234 	dma_addr_t phys_addr;
235 	spinlock_t lock;  /* Sync enabling lock */
236 	unsigned char cs[SPDIFRX_CS_BYTES_NB];
237 	unsigned char ub[SPDIFRX_UB_BYTES_NB];
238 	int irq;
239 	int refcount;
240 };
241 
242 static void stm32_spdifrx_dma_complete(void *data)
243 {
244 	struct stm32_spdifrx_data *spdifrx = (struct stm32_spdifrx_data *)data;
245 	struct platform_device *pdev = spdifrx->pdev;
246 	u32 *p_start = (u32 *)spdifrx->dmab->area;
247 	u32 *p_end = p_start + (2 * SPDIFRX_CS_BYTES_NB) - 1;
248 	u32 *ptr = p_start;
249 	u16 *ub_ptr = (short *)spdifrx->ub;
250 	int i = 0;
251 
252 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
253 			   SPDIFRX_CR_CBDMAEN,
254 			   (unsigned int)~SPDIFRX_CR_CBDMAEN);
255 
256 	if (!spdifrx->dmab->area)
257 		return;
258 
259 	while (ptr <= p_end) {
260 		if (*ptr & SPDIFRX_CSR_SOB)
261 			break;
262 		ptr++;
263 	}
264 
265 	if (ptr > p_end) {
266 		dev_err(&pdev->dev, "Start of S/PDIF block not found\n");
267 		return;
268 	}
269 
270 	while (i < SPDIFRX_CS_BYTES_NB) {
271 		spdifrx->cs[i] = (unsigned char)SPDIFRX_CSR_CSGET(*ptr);
272 		*ub_ptr++ = SPDIFRX_CSR_USRGET(*ptr++);
273 		if (ptr > p_end) {
274 			dev_err(&pdev->dev, "Failed to get channel status\n");
275 			return;
276 		}
277 		i++;
278 	}
279 
280 	complete(&spdifrx->cs_completion);
281 }
282 
283 static int stm32_spdifrx_dma_ctrl_start(struct stm32_spdifrx_data *spdifrx)
284 {
285 	dma_cookie_t cookie;
286 	int err;
287 
288 	spdifrx->desc = dmaengine_prep_slave_single(spdifrx->ctrl_chan,
289 						    spdifrx->dmab->addr,
290 						    SPDIFRX_CSR_BUF_LENGTH,
291 						    DMA_DEV_TO_MEM,
292 						    DMA_CTRL_ACK);
293 	if (!spdifrx->desc)
294 		return -EINVAL;
295 
296 	spdifrx->desc->callback = stm32_spdifrx_dma_complete;
297 	spdifrx->desc->callback_param = spdifrx;
298 	cookie = dmaengine_submit(spdifrx->desc);
299 	err = dma_submit_error(cookie);
300 	if (err)
301 		return -EINVAL;
302 
303 	dma_async_issue_pending(spdifrx->ctrl_chan);
304 
305 	return 0;
306 }
307 
308 static void stm32_spdifrx_dma_ctrl_stop(struct stm32_spdifrx_data *spdifrx)
309 {
310 	dmaengine_terminate_async(spdifrx->ctrl_chan);
311 }
312 
313 static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
314 {
315 	int cr, cr_mask, imr, ret;
316 
317 	/* Enable IRQs */
318 	imr = SPDIFRX_IMR_IFEIE | SPDIFRX_IMR_SYNCDIE | SPDIFRX_IMR_PERRIE;
319 	ret = regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IMR, imr, imr);
320 	if (ret)
321 		return ret;
322 
323 	spin_lock(&spdifrx->lock);
324 
325 	spdifrx->refcount++;
326 
327 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_CR, &cr);
328 
329 	if (!(cr & SPDIFRX_CR_SPDIFEN_MASK)) {
330 		/*
331 		 * Start sync if SPDIFRX is still in idle state.
332 		 * SPDIFRX reception enabled when sync done
333 		 */
334 		dev_dbg(&spdifrx->pdev->dev, "start synchronization\n");
335 
336 		/*
337 		 * SPDIFRX configuration:
338 		 * Wait for activity before starting sync process. This avoid
339 		 * to issue sync errors when spdif signal is missing on input.
340 		 * Preamble, CS, user, validity and parity error bits not copied
341 		 * to DR register.
342 		 */
343 		cr = SPDIFRX_CR_WFA | SPDIFRX_CR_PMSK | SPDIFRX_CR_VMSK |
344 		     SPDIFRX_CR_CUMSK | SPDIFRX_CR_PTMSK | SPDIFRX_CR_RXSTEO;
345 		cr_mask = cr;
346 
347 		cr |= SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_SYNC);
348 		cr_mask |= SPDIFRX_CR_SPDIFEN_MASK;
349 		ret = regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
350 					 cr_mask, cr);
351 		if (ret < 0)
352 			dev_err(&spdifrx->pdev->dev,
353 				"Failed to start synchronization\n");
354 	}
355 
356 	spin_unlock(&spdifrx->lock);
357 
358 	return ret;
359 }
360 
361 static void stm32_spdifrx_stop(struct stm32_spdifrx_data *spdifrx)
362 {
363 	int cr, cr_mask, reg;
364 
365 	spin_lock(&spdifrx->lock);
366 
367 	if (--spdifrx->refcount) {
368 		spin_unlock(&spdifrx->lock);
369 		return;
370 	}
371 
372 	cr = SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_DISABLE);
373 	cr_mask = SPDIFRX_CR_SPDIFEN_MASK | SPDIFRX_CR_RXDMAEN;
374 
375 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR, cr_mask, cr);
376 
377 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IMR,
378 			   SPDIFRX_XIMR_MASK, 0);
379 
380 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IFCR,
381 			   SPDIFRX_XIFCR_MASK, SPDIFRX_XIFCR_MASK);
382 
383 	/* dummy read to clear CSRNE and RXNE in status register */
384 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_DR, &reg);
385 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_CSR, &reg);
386 
387 	spin_unlock(&spdifrx->lock);
388 }
389 
390 static int stm32_spdifrx_dma_ctrl_register(struct device *dev,
391 					   struct stm32_spdifrx_data *spdifrx)
392 {
393 	int ret;
394 
395 	spdifrx->dmab = devm_kzalloc(dev, sizeof(struct snd_dma_buffer),
396 				     GFP_KERNEL);
397 	if (!spdifrx->dmab)
398 		return -ENOMEM;
399 
400 	spdifrx->dmab->dev.type = SNDRV_DMA_TYPE_DEV_IRAM;
401 	spdifrx->dmab->dev.dev = dev;
402 	ret = snd_dma_alloc_pages(spdifrx->dmab->dev.type, dev,
403 				  SPDIFRX_CSR_BUF_LENGTH, spdifrx->dmab);
404 	if (ret < 0) {
405 		dev_err(dev, "snd_dma_alloc_pages returned error %d\n", ret);
406 		return ret;
407 	}
408 
409 	spdifrx->ctrl_chan = dma_request_chan(dev, "rx-ctrl");
410 	if (!spdifrx->ctrl_chan) {
411 		dev_err(dev, "dma_request_slave_channel failed\n");
412 		return -EINVAL;
413 	}
414 
415 	spdifrx->slave_config.direction = DMA_DEV_TO_MEM;
416 	spdifrx->slave_config.src_addr = (dma_addr_t)(spdifrx->phys_addr +
417 					 STM32_SPDIFRX_CSR);
418 	spdifrx->slave_config.dst_addr = spdifrx->dmab->addr;
419 	spdifrx->slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
420 	spdifrx->slave_config.src_maxburst = 1;
421 
422 	ret = dmaengine_slave_config(spdifrx->ctrl_chan,
423 				     &spdifrx->slave_config);
424 	if (ret < 0) {
425 		dev_err(dev, "dmaengine_slave_config returned error %d\n", ret);
426 		dma_release_channel(spdifrx->ctrl_chan);
427 		spdifrx->ctrl_chan = NULL;
428 	}
429 
430 	return ret;
431 };
432 
433 static const char * const spdifrx_enum_input[] = {
434 	"in0", "in1", "in2", "in3"
435 };
436 
437 /*  By default CS bits are retrieved from channel A */
438 static const char * const spdifrx_enum_cs_channel[] = {
439 	"A", "B"
440 };
441 
442 static SOC_ENUM_SINGLE_DECL(ctrl_enum_input,
443 			    STM32_SPDIFRX_CR, SPDIFRX_CR_INSEL_SHIFT,
444 			    spdifrx_enum_input);
445 
446 static SOC_ENUM_SINGLE_DECL(ctrl_enum_cs_channel,
447 			    STM32_SPDIFRX_CR, SPDIFRX_CR_CHSEL_SHIFT,
448 			    spdifrx_enum_cs_channel);
449 
450 static int stm32_spdifrx_info(struct snd_kcontrol *kcontrol,
451 			      struct snd_ctl_elem_info *uinfo)
452 {
453 	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
454 	uinfo->count = 1;
455 
456 	return 0;
457 }
458 
459 static int stm32_spdifrx_ub_info(struct snd_kcontrol *kcontrol,
460 				 struct snd_ctl_elem_info *uinfo)
461 {
462 	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
463 	uinfo->count = 1;
464 
465 	return 0;
466 }
467 
468 static int stm32_spdifrx_get_ctrl_data(struct stm32_spdifrx_data *spdifrx)
469 {
470 	int ret = 0;
471 
472 	memset(spdifrx->cs, 0, SPDIFRX_CS_BYTES_NB);
473 	memset(spdifrx->ub, 0, SPDIFRX_UB_BYTES_NB);
474 
475 	ret = stm32_spdifrx_dma_ctrl_start(spdifrx);
476 	if (ret < 0)
477 		return ret;
478 
479 	ret = clk_prepare_enable(spdifrx->kclk);
480 	if (ret) {
481 		dev_err(&spdifrx->pdev->dev, "Enable kclk failed: %d\n", ret);
482 		return ret;
483 	}
484 
485 	ret = regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
486 				 SPDIFRX_CR_CBDMAEN, SPDIFRX_CR_CBDMAEN);
487 	if (ret < 0)
488 		goto end;
489 
490 	ret = stm32_spdifrx_start_sync(spdifrx);
491 	if (ret < 0)
492 		goto end;
493 
494 	if (wait_for_completion_interruptible_timeout(&spdifrx->cs_completion,
495 						      msecs_to_jiffies(100))
496 						      <= 0) {
497 		dev_err(&spdifrx->pdev->dev, "Failed to get control data\n");
498 		ret = -EAGAIN;
499 	}
500 
501 	stm32_spdifrx_stop(spdifrx);
502 	stm32_spdifrx_dma_ctrl_stop(spdifrx);
503 
504 end:
505 	clk_disable_unprepare(spdifrx->kclk);
506 
507 	return ret;
508 }
509 
510 static int stm32_spdifrx_capture_get(struct snd_kcontrol *kcontrol,
511 				     struct snd_ctl_elem_value *ucontrol)
512 {
513 	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
514 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
515 
516 	stm32_spdifrx_get_ctrl_data(spdifrx);
517 
518 	ucontrol->value.iec958.status[0] = spdifrx->cs[0];
519 	ucontrol->value.iec958.status[1] = spdifrx->cs[1];
520 	ucontrol->value.iec958.status[2] = spdifrx->cs[2];
521 	ucontrol->value.iec958.status[3] = spdifrx->cs[3];
522 	ucontrol->value.iec958.status[4] = spdifrx->cs[4];
523 
524 	return 0;
525 }
526 
527 static int stm32_spdif_user_bits_get(struct snd_kcontrol *kcontrol,
528 				     struct snd_ctl_elem_value *ucontrol)
529 {
530 	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
531 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
532 
533 	stm32_spdifrx_get_ctrl_data(spdifrx);
534 
535 	ucontrol->value.iec958.status[0] = spdifrx->ub[0];
536 	ucontrol->value.iec958.status[1] = spdifrx->ub[1];
537 	ucontrol->value.iec958.status[2] = spdifrx->ub[2];
538 	ucontrol->value.iec958.status[3] = spdifrx->ub[3];
539 	ucontrol->value.iec958.status[4] = spdifrx->ub[4];
540 
541 	return 0;
542 }
543 
544 static struct snd_kcontrol_new stm32_spdifrx_iec_ctrls[] = {
545 	/* Channel status control */
546 	{
547 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
548 		.name = SNDRV_CTL_NAME_IEC958("", CAPTURE, DEFAULT),
549 		.access = SNDRV_CTL_ELEM_ACCESS_READ |
550 			  SNDRV_CTL_ELEM_ACCESS_VOLATILE,
551 		.info = stm32_spdifrx_info,
552 		.get = stm32_spdifrx_capture_get,
553 	},
554 	/* User bits control */
555 	{
556 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
557 		.name = "IEC958 User Bit Capture Default",
558 		.access = SNDRV_CTL_ELEM_ACCESS_READ |
559 			  SNDRV_CTL_ELEM_ACCESS_VOLATILE,
560 		.info = stm32_spdifrx_ub_info,
561 		.get = stm32_spdif_user_bits_get,
562 	},
563 };
564 
565 static struct snd_kcontrol_new stm32_spdifrx_ctrls[] = {
566 	SOC_ENUM("SPDIFRX input", ctrl_enum_input),
567 	SOC_ENUM("SPDIFRX CS channel", ctrl_enum_cs_channel),
568 };
569 
570 static int stm32_spdifrx_dai_register_ctrls(struct snd_soc_dai *cpu_dai)
571 {
572 	int ret;
573 
574 	ret = snd_soc_add_dai_controls(cpu_dai, stm32_spdifrx_iec_ctrls,
575 				       ARRAY_SIZE(stm32_spdifrx_iec_ctrls));
576 	if (ret < 0)
577 		return ret;
578 
579 	return snd_soc_add_component_controls(cpu_dai->component,
580 					      stm32_spdifrx_ctrls,
581 					      ARRAY_SIZE(stm32_spdifrx_ctrls));
582 }
583 
584 static int stm32_spdifrx_dai_probe(struct snd_soc_dai *cpu_dai)
585 {
586 	struct stm32_spdifrx_data *spdifrx = dev_get_drvdata(cpu_dai->dev);
587 
588 	spdifrx->dma_params.addr = (dma_addr_t)(spdifrx->phys_addr +
589 				   STM32_SPDIFRX_DR);
590 	spdifrx->dma_params.maxburst = 1;
591 
592 	snd_soc_dai_init_dma_data(cpu_dai, NULL, &spdifrx->dma_params);
593 
594 	return stm32_spdifrx_dai_register_ctrls(cpu_dai);
595 }
596 
597 static bool stm32_spdifrx_readable_reg(struct device *dev, unsigned int reg)
598 {
599 	switch (reg) {
600 	case STM32_SPDIFRX_CR:
601 	case STM32_SPDIFRX_IMR:
602 	case STM32_SPDIFRX_SR:
603 	case STM32_SPDIFRX_IFCR:
604 	case STM32_SPDIFRX_DR:
605 	case STM32_SPDIFRX_CSR:
606 	case STM32_SPDIFRX_DIR:
607 		return true;
608 	default:
609 		return false;
610 	}
611 }
612 
613 static bool stm32_spdifrx_volatile_reg(struct device *dev, unsigned int reg)
614 {
615 	if (reg == STM32_SPDIFRX_DR)
616 		return true;
617 
618 	return false;
619 }
620 
621 static bool stm32_spdifrx_writeable_reg(struct device *dev, unsigned int reg)
622 {
623 	switch (reg) {
624 	case STM32_SPDIFRX_CR:
625 	case STM32_SPDIFRX_IMR:
626 	case STM32_SPDIFRX_IFCR:
627 		return true;
628 	default:
629 		return false;
630 	}
631 }
632 
633 static const struct regmap_config stm32_h7_spdifrx_regmap_conf = {
634 	.reg_bits = 32,
635 	.reg_stride = 4,
636 	.val_bits = 32,
637 	.max_register = STM32_SPDIFRX_DIR,
638 	.readable_reg = stm32_spdifrx_readable_reg,
639 	.volatile_reg = stm32_spdifrx_volatile_reg,
640 	.writeable_reg = stm32_spdifrx_writeable_reg,
641 	.fast_io = true,
642 };
643 
644 static irqreturn_t stm32_spdifrx_isr(int irq, void *devid)
645 {
646 	struct stm32_spdifrx_data *spdifrx = (struct stm32_spdifrx_data *)devid;
647 	struct snd_pcm_substream *substream = spdifrx->substream;
648 	struct platform_device *pdev = spdifrx->pdev;
649 	unsigned int cr, mask, sr, imr;
650 	unsigned int flags;
651 	int err = 0, err_xrun = 0;
652 
653 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_SR, &sr);
654 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_IMR, &imr);
655 
656 	mask = imr & SPDIFRX_XIMR_MASK;
657 	/* SERR, TERR, FERR IRQs are generated if IFEIE is set */
658 	if (mask & SPDIFRX_IMR_IFEIE)
659 		mask |= (SPDIFRX_IMR_IFEIE << 1) | (SPDIFRX_IMR_IFEIE << 2);
660 
661 	flags = sr & mask;
662 	if (!flags) {
663 		dev_err(&pdev->dev, "Unexpected IRQ. rflags=%#x, imr=%#x\n",
664 			sr, imr);
665 		return IRQ_NONE;
666 	}
667 
668 	/* Clear IRQs */
669 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IFCR,
670 			   SPDIFRX_XIFCR_MASK, flags);
671 
672 	if (flags & SPDIFRX_SR_PERR) {
673 		dev_dbg(&pdev->dev, "Parity error\n");
674 		err_xrun = 1;
675 	}
676 
677 	if (flags & SPDIFRX_SR_OVR) {
678 		dev_dbg(&pdev->dev, "Overrun error\n");
679 		err_xrun = 1;
680 	}
681 
682 	if (flags & SPDIFRX_SR_SBD)
683 		dev_dbg(&pdev->dev, "Synchronization block detected\n");
684 
685 	if (flags & SPDIFRX_SR_SYNCD) {
686 		dev_dbg(&pdev->dev, "Synchronization done\n");
687 
688 		/* Enable spdifrx */
689 		cr = SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_ENABLE);
690 		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
691 				   SPDIFRX_CR_SPDIFEN_MASK, cr);
692 	}
693 
694 	if (flags & SPDIFRX_SR_FERR) {
695 		dev_dbg(&pdev->dev, "Frame error\n");
696 		err = 1;
697 	}
698 
699 	if (flags & SPDIFRX_SR_SERR) {
700 		dev_dbg(&pdev->dev, "Synchronization error\n");
701 		err = 1;
702 	}
703 
704 	if (flags & SPDIFRX_SR_TERR) {
705 		dev_dbg(&pdev->dev, "Timeout error\n");
706 		err = 1;
707 	}
708 
709 	if (err) {
710 		/* SPDIFRX in STATE_STOP. Disable SPDIFRX to clear errors */
711 		cr = SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_DISABLE);
712 		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
713 				   SPDIFRX_CR_SPDIFEN_MASK, cr);
714 
715 		if (substream)
716 			snd_pcm_stop(substream, SNDRV_PCM_STATE_DISCONNECTED);
717 
718 		return IRQ_HANDLED;
719 	}
720 
721 	if (err_xrun && substream)
722 		snd_pcm_stop_xrun(substream);
723 
724 	return IRQ_HANDLED;
725 }
726 
727 static int stm32_spdifrx_startup(struct snd_pcm_substream *substream,
728 				 struct snd_soc_dai *cpu_dai)
729 {
730 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
731 	int ret;
732 
733 	spdifrx->substream = substream;
734 
735 	ret = clk_prepare_enable(spdifrx->kclk);
736 	if (ret)
737 		dev_err(&spdifrx->pdev->dev, "Enable kclk failed: %d\n", ret);
738 
739 	return ret;
740 }
741 
742 static int stm32_spdifrx_hw_params(struct snd_pcm_substream *substream,
743 				   struct snd_pcm_hw_params *params,
744 				   struct snd_soc_dai *cpu_dai)
745 {
746 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
747 	int data_size = params_width(params);
748 	int fmt;
749 
750 	switch (data_size) {
751 	case 16:
752 		fmt = SPDIFRX_DRFMT_PACKED;
753 		spdifrx->dma_params.addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
754 		break;
755 	case 32:
756 		fmt = SPDIFRX_DRFMT_LEFT;
757 		spdifrx->dma_params.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
758 		break;
759 	default:
760 		dev_err(&spdifrx->pdev->dev, "Unexpected data format\n");
761 		return -EINVAL;
762 	}
763 
764 	snd_soc_dai_init_dma_data(cpu_dai, NULL, &spdifrx->dma_params);
765 
766 	return regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
767 				  SPDIFRX_CR_DRFMT_MASK,
768 				  SPDIFRX_CR_DRFMTSET(fmt));
769 }
770 
771 static int stm32_spdifrx_trigger(struct snd_pcm_substream *substream, int cmd,
772 				 struct snd_soc_dai *cpu_dai)
773 {
774 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
775 	int ret = 0;
776 
777 	switch (cmd) {
778 	case SNDRV_PCM_TRIGGER_START:
779 	case SNDRV_PCM_TRIGGER_RESUME:
780 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
781 		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IMR,
782 				   SPDIFRX_IMR_OVRIE, SPDIFRX_IMR_OVRIE);
783 
784 		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
785 				   SPDIFRX_CR_RXDMAEN, SPDIFRX_CR_RXDMAEN);
786 
787 		ret = stm32_spdifrx_start_sync(spdifrx);
788 		break;
789 	case SNDRV_PCM_TRIGGER_SUSPEND:
790 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
791 	case SNDRV_PCM_TRIGGER_STOP:
792 		stm32_spdifrx_stop(spdifrx);
793 		break;
794 	default:
795 		return -EINVAL;
796 	}
797 
798 	return ret;
799 }
800 
801 static void stm32_spdifrx_shutdown(struct snd_pcm_substream *substream,
802 				   struct snd_soc_dai *cpu_dai)
803 {
804 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
805 
806 	spdifrx->substream = NULL;
807 	clk_disable_unprepare(spdifrx->kclk);
808 }
809 
810 static const struct snd_soc_dai_ops stm32_spdifrx_pcm_dai_ops = {
811 	.startup	= stm32_spdifrx_startup,
812 	.hw_params	= stm32_spdifrx_hw_params,
813 	.trigger	= stm32_spdifrx_trigger,
814 	.shutdown	= stm32_spdifrx_shutdown,
815 };
816 
817 static struct snd_soc_dai_driver stm32_spdifrx_dai[] = {
818 	{
819 		.name = "spdifrx-capture-cpu-dai",
820 		.probe = stm32_spdifrx_dai_probe,
821 		.capture = {
822 			.stream_name = "CPU-Capture",
823 			.channels_min = 1,
824 			.channels_max = 2,
825 			.rates = SNDRV_PCM_RATE_8000_192000,
826 			.formats = SNDRV_PCM_FMTBIT_S32_LE |
827 				   SNDRV_PCM_FMTBIT_S16_LE,
828 		},
829 		.ops = &stm32_spdifrx_pcm_dai_ops,
830 	}
831 };
832 
833 static const struct snd_pcm_hardware stm32_spdifrx_pcm_hw = {
834 	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_MMAP,
835 	.buffer_bytes_max = 8 * PAGE_SIZE,
836 	.period_bytes_max = 2048, /* MDMA constraint */
837 	.periods_min = 2,
838 	.periods_max = 8,
839 };
840 
841 static const struct snd_soc_component_driver stm32_spdifrx_component = {
842 	.name = "stm32-spdifrx",
843 };
844 
845 static const struct snd_dmaengine_pcm_config stm32_spdifrx_pcm_config = {
846 	.pcm_hardware = &stm32_spdifrx_pcm_hw,
847 	.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
848 };
849 
850 static const struct of_device_id stm32_spdifrx_ids[] = {
851 	{
852 		.compatible = "st,stm32h7-spdifrx",
853 		.data = &stm32_h7_spdifrx_regmap_conf
854 	},
855 	{}
856 };
857 
858 static int stm_spdifrx_parse_of(struct platform_device *pdev,
859 				struct stm32_spdifrx_data *spdifrx)
860 {
861 	struct device_node *np = pdev->dev.of_node;
862 	const struct of_device_id *of_id;
863 	struct resource *res;
864 
865 	if (!np)
866 		return -ENODEV;
867 
868 	of_id = of_match_device(stm32_spdifrx_ids, &pdev->dev);
869 	if (of_id)
870 		spdifrx->regmap_conf =
871 			(const struct regmap_config *)of_id->data;
872 	else
873 		return -EINVAL;
874 
875 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
876 	spdifrx->base = devm_ioremap_resource(&pdev->dev, res);
877 	if (IS_ERR(spdifrx->base))
878 		return PTR_ERR(spdifrx->base);
879 
880 	spdifrx->phys_addr = res->start;
881 
882 	spdifrx->kclk = devm_clk_get(&pdev->dev, "kclk");
883 	if (IS_ERR(spdifrx->kclk)) {
884 		dev_err(&pdev->dev, "Could not get kclk\n");
885 		return PTR_ERR(spdifrx->kclk);
886 	}
887 
888 	spdifrx->irq = platform_get_irq(pdev, 0);
889 	if (spdifrx->irq < 0) {
890 		dev_err(&pdev->dev, "No irq for node %s\n", pdev->name);
891 		return spdifrx->irq;
892 	}
893 
894 	return 0;
895 }
896 
897 static int stm32_spdifrx_probe(struct platform_device *pdev)
898 {
899 	struct stm32_spdifrx_data *spdifrx;
900 	struct reset_control *rst;
901 	const struct snd_dmaengine_pcm_config *pcm_config = NULL;
902 	int ret;
903 
904 	spdifrx = devm_kzalloc(&pdev->dev, sizeof(*spdifrx), GFP_KERNEL);
905 	if (!spdifrx)
906 		return -ENOMEM;
907 
908 	spdifrx->pdev = pdev;
909 	init_completion(&spdifrx->cs_completion);
910 	spin_lock_init(&spdifrx->lock);
911 
912 	platform_set_drvdata(pdev, spdifrx);
913 
914 	ret = stm_spdifrx_parse_of(pdev, spdifrx);
915 	if (ret)
916 		return ret;
917 
918 	spdifrx->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "kclk",
919 						    spdifrx->base,
920 						    spdifrx->regmap_conf);
921 	if (IS_ERR(spdifrx->regmap)) {
922 		dev_err(&pdev->dev, "Regmap init failed\n");
923 		return PTR_ERR(spdifrx->regmap);
924 	}
925 
926 	ret = devm_request_irq(&pdev->dev, spdifrx->irq, stm32_spdifrx_isr, 0,
927 			       dev_name(&pdev->dev), spdifrx);
928 	if (ret) {
929 		dev_err(&pdev->dev, "IRQ request returned %d\n", ret);
930 		return ret;
931 	}
932 
933 	rst = devm_reset_control_get_exclusive(&pdev->dev, NULL);
934 	if (!IS_ERR(rst)) {
935 		reset_control_assert(rst);
936 		udelay(2);
937 		reset_control_deassert(rst);
938 	}
939 
940 	ret = devm_snd_soc_register_component(&pdev->dev,
941 					      &stm32_spdifrx_component,
942 					      stm32_spdifrx_dai,
943 					      ARRAY_SIZE(stm32_spdifrx_dai));
944 	if (ret)
945 		return ret;
946 
947 	ret = stm32_spdifrx_dma_ctrl_register(&pdev->dev, spdifrx);
948 	if (ret)
949 		goto error;
950 
951 	pcm_config = &stm32_spdifrx_pcm_config;
952 	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, pcm_config, 0);
953 	if (ret) {
954 		dev_err(&pdev->dev, "PCM DMA register returned %d\n", ret);
955 		goto error;
956 	}
957 
958 	return 0;
959 
960 error:
961 	if (spdifrx->ctrl_chan)
962 		dma_release_channel(spdifrx->ctrl_chan);
963 	if (spdifrx->dmab)
964 		snd_dma_free_pages(spdifrx->dmab);
965 
966 	return ret;
967 }
968 
969 static int stm32_spdifrx_remove(struct platform_device *pdev)
970 {
971 	struct stm32_spdifrx_data *spdifrx = platform_get_drvdata(pdev);
972 
973 	if (spdifrx->ctrl_chan)
974 		dma_release_channel(spdifrx->ctrl_chan);
975 
976 	if (spdifrx->dmab)
977 		snd_dma_free_pages(spdifrx->dmab);
978 
979 	return 0;
980 }
981 
982 MODULE_DEVICE_TABLE(of, stm32_spdifrx_ids);
983 
984 static struct platform_driver stm32_spdifrx_driver = {
985 	.driver = {
986 		.name = "st,stm32-spdifrx",
987 		.of_match_table = stm32_spdifrx_ids,
988 	},
989 	.probe = stm32_spdifrx_probe,
990 	.remove = stm32_spdifrx_remove,
991 };
992 
993 module_platform_driver(stm32_spdifrx_driver);
994 
995 MODULE_DESCRIPTION("STM32 Soc spdifrx Interface");
996 MODULE_AUTHOR("Olivier Moysan, <olivier.moysan@st.com>");
997 MODULE_ALIAS("platform:stm32-spdifrx");
998 MODULE_LICENSE("GPL v2");
999