xref: /openbmc/linux/sound/soc/stm/stm32_spdifrx.c (revision 2b77dcc5)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * STM32 ALSA SoC Digital Audio Interface (SPDIF-rx) driver.
4  *
5  * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
6  * Author(s): Olivier Moysan <olivier.moysan@st.com> for STMicroelectronics.
7  */
8 
9 #include <linux/bitfield.h>
10 #include <linux/clk.h>
11 #include <linux/completion.h>
12 #include <linux/delay.h>
13 #include <linux/module.h>
14 #include <linux/of_platform.h>
15 #include <linux/pinctrl/consumer.h>
16 #include <linux/regmap.h>
17 #include <linux/reset.h>
18 
19 #include <sound/dmaengine_pcm.h>
20 #include <sound/pcm_params.h>
21 
22 /* SPDIF-rx Register Map */
23 #define STM32_SPDIFRX_CR	0x00
24 #define STM32_SPDIFRX_IMR	0x04
25 #define STM32_SPDIFRX_SR	0x08
26 #define STM32_SPDIFRX_IFCR	0x0C
27 #define STM32_SPDIFRX_DR	0x10
28 #define STM32_SPDIFRX_CSR	0x14
29 #define STM32_SPDIFRX_DIR	0x18
30 #define STM32_SPDIFRX_VERR	0x3F4
31 #define STM32_SPDIFRX_IDR	0x3F8
32 #define STM32_SPDIFRX_SIDR	0x3FC
33 
34 /* Bit definition for SPDIF_CR register */
35 #define SPDIFRX_CR_SPDIFEN_SHIFT	0
36 #define SPDIFRX_CR_SPDIFEN_MASK	GENMASK(1, SPDIFRX_CR_SPDIFEN_SHIFT)
37 #define SPDIFRX_CR_SPDIFENSET(x)	((x) << SPDIFRX_CR_SPDIFEN_SHIFT)
38 
39 #define SPDIFRX_CR_RXDMAEN	BIT(2)
40 #define SPDIFRX_CR_RXSTEO	BIT(3)
41 
42 #define SPDIFRX_CR_DRFMT_SHIFT	4
43 #define SPDIFRX_CR_DRFMT_MASK	GENMASK(5, SPDIFRX_CR_DRFMT_SHIFT)
44 #define SPDIFRX_CR_DRFMTSET(x)	((x) << SPDIFRX_CR_DRFMT_SHIFT)
45 
46 #define SPDIFRX_CR_PMSK		BIT(6)
47 #define SPDIFRX_CR_VMSK		BIT(7)
48 #define SPDIFRX_CR_CUMSK	BIT(8)
49 #define SPDIFRX_CR_PTMSK	BIT(9)
50 #define SPDIFRX_CR_CBDMAEN	BIT(10)
51 #define SPDIFRX_CR_CHSEL_SHIFT	11
52 #define SPDIFRX_CR_CHSEL	BIT(SPDIFRX_CR_CHSEL_SHIFT)
53 
54 #define SPDIFRX_CR_NBTR_SHIFT	12
55 #define SPDIFRX_CR_NBTR_MASK	GENMASK(13, SPDIFRX_CR_NBTR_SHIFT)
56 #define SPDIFRX_CR_NBTRSET(x)	((x) << SPDIFRX_CR_NBTR_SHIFT)
57 
58 #define SPDIFRX_CR_WFA		BIT(14)
59 
60 #define SPDIFRX_CR_INSEL_SHIFT	16
61 #define SPDIFRX_CR_INSEL_MASK	GENMASK(18, PDIFRX_CR_INSEL_SHIFT)
62 #define SPDIFRX_CR_INSELSET(x)	((x) << SPDIFRX_CR_INSEL_SHIFT)
63 
64 #define SPDIFRX_CR_CKSEN_SHIFT	20
65 #define SPDIFRX_CR_CKSEN	BIT(20)
66 #define SPDIFRX_CR_CKSBKPEN	BIT(21)
67 
68 /* Bit definition for SPDIFRX_IMR register */
69 #define SPDIFRX_IMR_RXNEI	BIT(0)
70 #define SPDIFRX_IMR_CSRNEIE	BIT(1)
71 #define SPDIFRX_IMR_PERRIE	BIT(2)
72 #define SPDIFRX_IMR_OVRIE	BIT(3)
73 #define SPDIFRX_IMR_SBLKIE	BIT(4)
74 #define SPDIFRX_IMR_SYNCDIE	BIT(5)
75 #define SPDIFRX_IMR_IFEIE	BIT(6)
76 
77 #define SPDIFRX_XIMR_MASK	GENMASK(6, 0)
78 
79 /* Bit definition for SPDIFRX_SR register */
80 #define SPDIFRX_SR_RXNE		BIT(0)
81 #define SPDIFRX_SR_CSRNE	BIT(1)
82 #define SPDIFRX_SR_PERR		BIT(2)
83 #define SPDIFRX_SR_OVR		BIT(3)
84 #define SPDIFRX_SR_SBD		BIT(4)
85 #define SPDIFRX_SR_SYNCD	BIT(5)
86 #define SPDIFRX_SR_FERR		BIT(6)
87 #define SPDIFRX_SR_SERR		BIT(7)
88 #define SPDIFRX_SR_TERR		BIT(8)
89 
90 #define SPDIFRX_SR_WIDTH5_SHIFT	16
91 #define SPDIFRX_SR_WIDTH5_MASK	GENMASK(30, PDIFRX_SR_WIDTH5_SHIFT)
92 #define SPDIFRX_SR_WIDTH5SET(x)	((x) << SPDIFRX_SR_WIDTH5_SHIFT)
93 
94 /* Bit definition for SPDIFRX_IFCR register */
95 #define SPDIFRX_IFCR_PERRCF	BIT(2)
96 #define SPDIFRX_IFCR_OVRCF	BIT(3)
97 #define SPDIFRX_IFCR_SBDCF	BIT(4)
98 #define SPDIFRX_IFCR_SYNCDCF	BIT(5)
99 
100 #define SPDIFRX_XIFCR_MASK	GENMASK(5, 2)
101 
102 /* Bit definition for SPDIFRX_DR register (DRFMT = 0b00) */
103 #define SPDIFRX_DR0_DR_SHIFT	0
104 #define SPDIFRX_DR0_DR_MASK	GENMASK(23, SPDIFRX_DR0_DR_SHIFT)
105 #define SPDIFRX_DR0_DRSET(x)	((x) << SPDIFRX_DR0_DR_SHIFT)
106 
107 #define SPDIFRX_DR0_PE		BIT(24)
108 
109 #define SPDIFRX_DR0_V		BIT(25)
110 #define SPDIFRX_DR0_U		BIT(26)
111 #define SPDIFRX_DR0_C		BIT(27)
112 
113 #define SPDIFRX_DR0_PT_SHIFT	28
114 #define SPDIFRX_DR0_PT_MASK	GENMASK(29, SPDIFRX_DR0_PT_SHIFT)
115 #define SPDIFRX_DR0_PTSET(x)	((x) << SPDIFRX_DR0_PT_SHIFT)
116 
117 /* Bit definition for SPDIFRX_DR register (DRFMT = 0b01) */
118 #define  SPDIFRX_DR1_PE		BIT(0)
119 #define  SPDIFRX_DR1_V		BIT(1)
120 #define  SPDIFRX_DR1_U		BIT(2)
121 #define  SPDIFRX_DR1_C		BIT(3)
122 
123 #define  SPDIFRX_DR1_PT_SHIFT	4
124 #define  SPDIFRX_DR1_PT_MASK	GENMASK(5, SPDIFRX_DR1_PT_SHIFT)
125 #define  SPDIFRX_DR1_PTSET(x)	((x) << SPDIFRX_DR1_PT_SHIFT)
126 
127 #define SPDIFRX_DR1_DR_SHIFT	8
128 #define SPDIFRX_DR1_DR_MASK	GENMASK(31, SPDIFRX_DR1_DR_SHIFT)
129 #define SPDIFRX_DR1_DRSET(x)	((x) << SPDIFRX_DR1_DR_SHIFT)
130 
131 /* Bit definition for SPDIFRX_DR register (DRFMT = 0b10) */
132 #define SPDIFRX_DR1_DRNL1_SHIFT	0
133 #define SPDIFRX_DR1_DRNL1_MASK	GENMASK(15, SPDIFRX_DR1_DRNL1_SHIFT)
134 #define SPDIFRX_DR1_DRNL1SET(x)	((x) << SPDIFRX_DR1_DRNL1_SHIFT)
135 
136 #define SPDIFRX_DR1_DRNL2_SHIFT	16
137 #define SPDIFRX_DR1_DRNL2_MASK	GENMASK(31, SPDIFRX_DR1_DRNL2_SHIFT)
138 #define SPDIFRX_DR1_DRNL2SET(x)	((x) << SPDIFRX_DR1_DRNL2_SHIFT)
139 
140 /* Bit definition for SPDIFRX_CSR register */
141 #define SPDIFRX_CSR_USR_SHIFT	0
142 #define SPDIFRX_CSR_USR_MASK	GENMASK(15, SPDIFRX_CSR_USR_SHIFT)
143 #define SPDIFRX_CSR_USRGET(x)	(((x) & SPDIFRX_CSR_USR_MASK)\
144 				>> SPDIFRX_CSR_USR_SHIFT)
145 
146 #define SPDIFRX_CSR_CS_SHIFT	16
147 #define SPDIFRX_CSR_CS_MASK	GENMASK(23, SPDIFRX_CSR_CS_SHIFT)
148 #define SPDIFRX_CSR_CSGET(x)	(((x) & SPDIFRX_CSR_CS_MASK)\
149 				>> SPDIFRX_CSR_CS_SHIFT)
150 
151 #define SPDIFRX_CSR_SOB		BIT(24)
152 
153 /* Bit definition for SPDIFRX_DIR register */
154 #define SPDIFRX_DIR_THI_SHIFT	0
155 #define SPDIFRX_DIR_THI_MASK	GENMASK(12, SPDIFRX_DIR_THI_SHIFT)
156 #define SPDIFRX_DIR_THI_SET(x)	((x) << SPDIFRX_DIR_THI_SHIFT)
157 
158 #define SPDIFRX_DIR_TLO_SHIFT	16
159 #define SPDIFRX_DIR_TLO_MASK	GENMASK(28, SPDIFRX_DIR_TLO_SHIFT)
160 #define SPDIFRX_DIR_TLO_SET(x)	((x) << SPDIFRX_DIR_TLO_SHIFT)
161 
162 #define SPDIFRX_SPDIFEN_DISABLE	0x0
163 #define SPDIFRX_SPDIFEN_SYNC	0x1
164 #define SPDIFRX_SPDIFEN_ENABLE	0x3
165 
166 /* Bit definition for SPDIFRX_VERR register */
167 #define SPDIFRX_VERR_MIN_MASK	GENMASK(3, 0)
168 #define SPDIFRX_VERR_MAJ_MASK	GENMASK(7, 4)
169 
170 /* Bit definition for SPDIFRX_IDR register */
171 #define SPDIFRX_IDR_ID_MASK	GENMASK(31, 0)
172 
173 /* Bit definition for SPDIFRX_SIDR register */
174 #define SPDIFRX_SIDR_SID_MASK	GENMASK(31, 0)
175 
176 #define SPDIFRX_IPIDR_NUMBER	0x00130041
177 
178 #define SPDIFRX_IN1		0x1
179 #define SPDIFRX_IN2		0x2
180 #define SPDIFRX_IN3		0x3
181 #define SPDIFRX_IN4		0x4
182 #define SPDIFRX_IN5		0x5
183 #define SPDIFRX_IN6		0x6
184 #define SPDIFRX_IN7		0x7
185 #define SPDIFRX_IN8		0x8
186 
187 #define SPDIFRX_NBTR_NONE	0x0
188 #define SPDIFRX_NBTR_3		0x1
189 #define SPDIFRX_NBTR_15		0x2
190 #define SPDIFRX_NBTR_63		0x3
191 
192 #define SPDIFRX_DRFMT_RIGHT	0x0
193 #define SPDIFRX_DRFMT_LEFT	0x1
194 #define SPDIFRX_DRFMT_PACKED	0x2
195 
196 /* 192 CS bits in S/PDIF frame. i.e 24 CS bytes */
197 #define SPDIFRX_CS_BYTES_NB	24
198 #define SPDIFRX_UB_BYTES_NB	48
199 
200 /*
201  * CSR register is retrieved as a 32 bits word
202  * It contains 1 channel status byte and 2 user data bytes
203  * 2 S/PDIF frames are acquired to get all CS/UB bits
204  */
205 #define SPDIFRX_CSR_BUF_LENGTH	(SPDIFRX_CS_BYTES_NB * 4 * 2)
206 
207 /**
208  * struct stm32_spdifrx_data - private data of SPDIFRX
209  * @pdev: device data pointer
210  * @base: mmio register base virtual address
211  * @regmap: SPDIFRX register map pointer
212  * @regmap_conf: SPDIFRX register map configuration pointer
213  * @cs_completion: channel status retrieving completion
214  * @kclk: kernel clock feeding the SPDIFRX clock generator
215  * @dma_params: dma configuration data for rx channel
216  * @substream: PCM substream data pointer
217  * @dmab: dma buffer info pointer
218  * @ctrl_chan: dma channel for S/PDIF control bits
219  * @desc:dma async transaction descriptor
220  * @slave_config: dma slave channel runtime config pointer
221  * @phys_addr: SPDIFRX registers physical base address
222  * @lock: synchronization enabling lock
223  * @cs: channel status buffer
224  * @ub: user data buffer
225  * @irq: SPDIFRX interrupt line
226  * @refcount: keep count of opened DMA channels
227  */
228 struct stm32_spdifrx_data {
229 	struct platform_device *pdev;
230 	void __iomem *base;
231 	struct regmap *regmap;
232 	const struct regmap_config *regmap_conf;
233 	struct completion cs_completion;
234 	struct clk *kclk;
235 	struct snd_dmaengine_dai_dma_data dma_params;
236 	struct snd_pcm_substream *substream;
237 	struct snd_dma_buffer *dmab;
238 	struct dma_chan *ctrl_chan;
239 	struct dma_async_tx_descriptor *desc;
240 	struct dma_slave_config slave_config;
241 	dma_addr_t phys_addr;
242 	spinlock_t lock;  /* Sync enabling lock */
243 	unsigned char cs[SPDIFRX_CS_BYTES_NB];
244 	unsigned char ub[SPDIFRX_UB_BYTES_NB];
245 	int irq;
246 	int refcount;
247 };
248 
249 static void stm32_spdifrx_dma_complete(void *data)
250 {
251 	struct stm32_spdifrx_data *spdifrx = (struct stm32_spdifrx_data *)data;
252 	struct platform_device *pdev = spdifrx->pdev;
253 	u32 *p_start = (u32 *)spdifrx->dmab->area;
254 	u32 *p_end = p_start + (2 * SPDIFRX_CS_BYTES_NB) - 1;
255 	u32 *ptr = p_start;
256 	u16 *ub_ptr = (short *)spdifrx->ub;
257 	int i = 0;
258 
259 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
260 			   SPDIFRX_CR_CBDMAEN,
261 			   (unsigned int)~SPDIFRX_CR_CBDMAEN);
262 
263 	if (!spdifrx->dmab->area)
264 		return;
265 
266 	while (ptr <= p_end) {
267 		if (*ptr & SPDIFRX_CSR_SOB)
268 			break;
269 		ptr++;
270 	}
271 
272 	if (ptr > p_end) {
273 		dev_err(&pdev->dev, "Start of S/PDIF block not found\n");
274 		return;
275 	}
276 
277 	while (i < SPDIFRX_CS_BYTES_NB) {
278 		spdifrx->cs[i] = (unsigned char)SPDIFRX_CSR_CSGET(*ptr);
279 		*ub_ptr++ = SPDIFRX_CSR_USRGET(*ptr++);
280 		if (ptr > p_end) {
281 			dev_err(&pdev->dev, "Failed to get channel status\n");
282 			return;
283 		}
284 		i++;
285 	}
286 
287 	complete(&spdifrx->cs_completion);
288 }
289 
290 static int stm32_spdifrx_dma_ctrl_start(struct stm32_spdifrx_data *spdifrx)
291 {
292 	dma_cookie_t cookie;
293 	int err;
294 
295 	spdifrx->desc = dmaengine_prep_slave_single(spdifrx->ctrl_chan,
296 						    spdifrx->dmab->addr,
297 						    SPDIFRX_CSR_BUF_LENGTH,
298 						    DMA_DEV_TO_MEM,
299 						    DMA_CTRL_ACK);
300 	if (!spdifrx->desc)
301 		return -EINVAL;
302 
303 	spdifrx->desc->callback = stm32_spdifrx_dma_complete;
304 	spdifrx->desc->callback_param = spdifrx;
305 	cookie = dmaengine_submit(spdifrx->desc);
306 	err = dma_submit_error(cookie);
307 	if (err)
308 		return -EINVAL;
309 
310 	dma_async_issue_pending(spdifrx->ctrl_chan);
311 
312 	return 0;
313 }
314 
315 static void stm32_spdifrx_dma_ctrl_stop(struct stm32_spdifrx_data *spdifrx)
316 {
317 	dmaengine_terminate_async(spdifrx->ctrl_chan);
318 }
319 
320 static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
321 {
322 	int cr, cr_mask, imr, ret;
323 
324 	/* Enable IRQs */
325 	imr = SPDIFRX_IMR_IFEIE | SPDIFRX_IMR_SYNCDIE | SPDIFRX_IMR_PERRIE;
326 	ret = regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IMR, imr, imr);
327 	if (ret)
328 		return ret;
329 
330 	spin_lock(&spdifrx->lock);
331 
332 	spdifrx->refcount++;
333 
334 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_CR, &cr);
335 
336 	if (!(cr & SPDIFRX_CR_SPDIFEN_MASK)) {
337 		/*
338 		 * Start sync if SPDIFRX is still in idle state.
339 		 * SPDIFRX reception enabled when sync done
340 		 */
341 		dev_dbg(&spdifrx->pdev->dev, "start synchronization\n");
342 
343 		/*
344 		 * SPDIFRX configuration:
345 		 * Wait for activity before starting sync process. This avoid
346 		 * to issue sync errors when spdif signal is missing on input.
347 		 * Preamble, CS, user, validity and parity error bits not copied
348 		 * to DR register.
349 		 */
350 		cr = SPDIFRX_CR_WFA | SPDIFRX_CR_PMSK | SPDIFRX_CR_VMSK |
351 		     SPDIFRX_CR_CUMSK | SPDIFRX_CR_PTMSK | SPDIFRX_CR_RXSTEO;
352 		cr_mask = cr;
353 
354 		cr |= SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_SYNC);
355 		cr_mask |= SPDIFRX_CR_SPDIFEN_MASK;
356 		ret = regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
357 					 cr_mask, cr);
358 		if (ret < 0)
359 			dev_err(&spdifrx->pdev->dev,
360 				"Failed to start synchronization\n");
361 	}
362 
363 	spin_unlock(&spdifrx->lock);
364 
365 	return ret;
366 }
367 
368 static void stm32_spdifrx_stop(struct stm32_spdifrx_data *spdifrx)
369 {
370 	int cr, cr_mask, reg;
371 
372 	spin_lock(&spdifrx->lock);
373 
374 	if (--spdifrx->refcount) {
375 		spin_unlock(&spdifrx->lock);
376 		return;
377 	}
378 
379 	cr = SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_DISABLE);
380 	cr_mask = SPDIFRX_CR_SPDIFEN_MASK | SPDIFRX_CR_RXDMAEN;
381 
382 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR, cr_mask, cr);
383 
384 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IMR,
385 			   SPDIFRX_XIMR_MASK, 0);
386 
387 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IFCR,
388 			   SPDIFRX_XIFCR_MASK, SPDIFRX_XIFCR_MASK);
389 
390 	/* dummy read to clear CSRNE and RXNE in status register */
391 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_DR, &reg);
392 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_CSR, &reg);
393 
394 	spin_unlock(&spdifrx->lock);
395 }
396 
397 static int stm32_spdifrx_dma_ctrl_register(struct device *dev,
398 					   struct stm32_spdifrx_data *spdifrx)
399 {
400 	int ret;
401 
402 	spdifrx->ctrl_chan = dma_request_chan(dev, "rx-ctrl");
403 	if (IS_ERR(spdifrx->ctrl_chan)) {
404 		dev_err(dev, "dma_request_slave_channel failed\n");
405 		return PTR_ERR(spdifrx->ctrl_chan);
406 	}
407 
408 	spdifrx->dmab = devm_kzalloc(dev, sizeof(struct snd_dma_buffer),
409 				     GFP_KERNEL);
410 	if (!spdifrx->dmab)
411 		return -ENOMEM;
412 
413 	spdifrx->dmab->dev.type = SNDRV_DMA_TYPE_DEV_IRAM;
414 	spdifrx->dmab->dev.dev = dev;
415 	ret = snd_dma_alloc_pages(spdifrx->dmab->dev.type, dev,
416 				  SPDIFRX_CSR_BUF_LENGTH, spdifrx->dmab);
417 	if (ret < 0) {
418 		dev_err(dev, "snd_dma_alloc_pages returned error %d\n", ret);
419 		return ret;
420 	}
421 
422 	spdifrx->slave_config.direction = DMA_DEV_TO_MEM;
423 	spdifrx->slave_config.src_addr = (dma_addr_t)(spdifrx->phys_addr +
424 					 STM32_SPDIFRX_CSR);
425 	spdifrx->slave_config.dst_addr = spdifrx->dmab->addr;
426 	spdifrx->slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
427 	spdifrx->slave_config.src_maxburst = 1;
428 
429 	ret = dmaengine_slave_config(spdifrx->ctrl_chan,
430 				     &spdifrx->slave_config);
431 	if (ret < 0) {
432 		dev_err(dev, "dmaengine_slave_config returned error %d\n", ret);
433 		spdifrx->ctrl_chan = NULL;
434 	}
435 
436 	return ret;
437 };
438 
439 static const char * const spdifrx_enum_input[] = {
440 	"in0", "in1", "in2", "in3"
441 };
442 
443 /*  By default CS bits are retrieved from channel A */
444 static const char * const spdifrx_enum_cs_channel[] = {
445 	"A", "B"
446 };
447 
448 static SOC_ENUM_SINGLE_DECL(ctrl_enum_input,
449 			    STM32_SPDIFRX_CR, SPDIFRX_CR_INSEL_SHIFT,
450 			    spdifrx_enum_input);
451 
452 static SOC_ENUM_SINGLE_DECL(ctrl_enum_cs_channel,
453 			    STM32_SPDIFRX_CR, SPDIFRX_CR_CHSEL_SHIFT,
454 			    spdifrx_enum_cs_channel);
455 
456 static int stm32_spdifrx_info(struct snd_kcontrol *kcontrol,
457 			      struct snd_ctl_elem_info *uinfo)
458 {
459 	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
460 	uinfo->count = 1;
461 
462 	return 0;
463 }
464 
465 static int stm32_spdifrx_ub_info(struct snd_kcontrol *kcontrol,
466 				 struct snd_ctl_elem_info *uinfo)
467 {
468 	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
469 	uinfo->count = 1;
470 
471 	return 0;
472 }
473 
474 static int stm32_spdifrx_get_ctrl_data(struct stm32_spdifrx_data *spdifrx)
475 {
476 	int ret = 0;
477 
478 	memset(spdifrx->cs, 0, SPDIFRX_CS_BYTES_NB);
479 	memset(spdifrx->ub, 0, SPDIFRX_UB_BYTES_NB);
480 
481 	pinctrl_pm_select_default_state(&spdifrx->pdev->dev);
482 
483 	ret = stm32_spdifrx_dma_ctrl_start(spdifrx);
484 	if (ret < 0)
485 		return ret;
486 
487 	ret = clk_prepare_enable(spdifrx->kclk);
488 	if (ret) {
489 		dev_err(&spdifrx->pdev->dev, "Enable kclk failed: %d\n", ret);
490 		return ret;
491 	}
492 
493 	ret = regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
494 				 SPDIFRX_CR_CBDMAEN, SPDIFRX_CR_CBDMAEN);
495 	if (ret < 0)
496 		goto end;
497 
498 	ret = stm32_spdifrx_start_sync(spdifrx);
499 	if (ret < 0)
500 		goto end;
501 
502 	if (wait_for_completion_interruptible_timeout(&spdifrx->cs_completion,
503 						      msecs_to_jiffies(100))
504 						      <= 0) {
505 		dev_dbg(&spdifrx->pdev->dev, "Failed to get control data\n");
506 		ret = -EAGAIN;
507 	}
508 
509 	stm32_spdifrx_stop(spdifrx);
510 	stm32_spdifrx_dma_ctrl_stop(spdifrx);
511 
512 end:
513 	clk_disable_unprepare(spdifrx->kclk);
514 	pinctrl_pm_select_sleep_state(&spdifrx->pdev->dev);
515 
516 	return ret;
517 }
518 
519 static int stm32_spdifrx_capture_get(struct snd_kcontrol *kcontrol,
520 				     struct snd_ctl_elem_value *ucontrol)
521 {
522 	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
523 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
524 
525 	stm32_spdifrx_get_ctrl_data(spdifrx);
526 
527 	ucontrol->value.iec958.status[0] = spdifrx->cs[0];
528 	ucontrol->value.iec958.status[1] = spdifrx->cs[1];
529 	ucontrol->value.iec958.status[2] = spdifrx->cs[2];
530 	ucontrol->value.iec958.status[3] = spdifrx->cs[3];
531 	ucontrol->value.iec958.status[4] = spdifrx->cs[4];
532 
533 	return 0;
534 }
535 
536 static int stm32_spdif_user_bits_get(struct snd_kcontrol *kcontrol,
537 				     struct snd_ctl_elem_value *ucontrol)
538 {
539 	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
540 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
541 
542 	stm32_spdifrx_get_ctrl_data(spdifrx);
543 
544 	ucontrol->value.iec958.status[0] = spdifrx->ub[0];
545 	ucontrol->value.iec958.status[1] = spdifrx->ub[1];
546 	ucontrol->value.iec958.status[2] = spdifrx->ub[2];
547 	ucontrol->value.iec958.status[3] = spdifrx->ub[3];
548 	ucontrol->value.iec958.status[4] = spdifrx->ub[4];
549 
550 	return 0;
551 }
552 
553 static struct snd_kcontrol_new stm32_spdifrx_iec_ctrls[] = {
554 	/* Channel status control */
555 	{
556 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
557 		.name = SNDRV_CTL_NAME_IEC958("", CAPTURE, DEFAULT),
558 		.access = SNDRV_CTL_ELEM_ACCESS_READ |
559 			  SNDRV_CTL_ELEM_ACCESS_VOLATILE,
560 		.info = stm32_spdifrx_info,
561 		.get = stm32_spdifrx_capture_get,
562 	},
563 	/* User bits control */
564 	{
565 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
566 		.name = "IEC958 User Bit Capture Default",
567 		.access = SNDRV_CTL_ELEM_ACCESS_READ |
568 			  SNDRV_CTL_ELEM_ACCESS_VOLATILE,
569 		.info = stm32_spdifrx_ub_info,
570 		.get = stm32_spdif_user_bits_get,
571 	},
572 };
573 
574 static struct snd_kcontrol_new stm32_spdifrx_ctrls[] = {
575 	SOC_ENUM("SPDIFRX input", ctrl_enum_input),
576 	SOC_ENUM("SPDIFRX CS channel", ctrl_enum_cs_channel),
577 };
578 
579 static int stm32_spdifrx_dai_register_ctrls(struct snd_soc_dai *cpu_dai)
580 {
581 	int ret;
582 
583 	ret = snd_soc_add_dai_controls(cpu_dai, stm32_spdifrx_iec_ctrls,
584 				       ARRAY_SIZE(stm32_spdifrx_iec_ctrls));
585 	if (ret < 0)
586 		return ret;
587 
588 	return snd_soc_add_component_controls(cpu_dai->component,
589 					      stm32_spdifrx_ctrls,
590 					      ARRAY_SIZE(stm32_spdifrx_ctrls));
591 }
592 
593 static int stm32_spdifrx_dai_probe(struct snd_soc_dai *cpu_dai)
594 {
595 	struct stm32_spdifrx_data *spdifrx = dev_get_drvdata(cpu_dai->dev);
596 
597 	spdifrx->dma_params.addr = (dma_addr_t)(spdifrx->phys_addr +
598 				   STM32_SPDIFRX_DR);
599 	spdifrx->dma_params.maxburst = 1;
600 
601 	snd_soc_dai_init_dma_data(cpu_dai, NULL, &spdifrx->dma_params);
602 
603 	return stm32_spdifrx_dai_register_ctrls(cpu_dai);
604 }
605 
606 static bool stm32_spdifrx_readable_reg(struct device *dev, unsigned int reg)
607 {
608 	switch (reg) {
609 	case STM32_SPDIFRX_CR:
610 	case STM32_SPDIFRX_IMR:
611 	case STM32_SPDIFRX_SR:
612 	case STM32_SPDIFRX_IFCR:
613 	case STM32_SPDIFRX_DR:
614 	case STM32_SPDIFRX_CSR:
615 	case STM32_SPDIFRX_DIR:
616 	case STM32_SPDIFRX_VERR:
617 	case STM32_SPDIFRX_IDR:
618 	case STM32_SPDIFRX_SIDR:
619 		return true;
620 	default:
621 		return false;
622 	}
623 }
624 
625 static bool stm32_spdifrx_volatile_reg(struct device *dev, unsigned int reg)
626 {
627 	switch (reg) {
628 	case STM32_SPDIFRX_DR:
629 	case STM32_SPDIFRX_CSR:
630 	case STM32_SPDIFRX_SR:
631 	case STM32_SPDIFRX_DIR:
632 		return true;
633 	default:
634 		return false;
635 	}
636 }
637 
638 static bool stm32_spdifrx_writeable_reg(struct device *dev, unsigned int reg)
639 {
640 	switch (reg) {
641 	case STM32_SPDIFRX_CR:
642 	case STM32_SPDIFRX_IMR:
643 	case STM32_SPDIFRX_IFCR:
644 		return true;
645 	default:
646 		return false;
647 	}
648 }
649 
650 static const struct regmap_config stm32_h7_spdifrx_regmap_conf = {
651 	.reg_bits = 32,
652 	.reg_stride = 4,
653 	.val_bits = 32,
654 	.max_register = STM32_SPDIFRX_SIDR,
655 	.readable_reg = stm32_spdifrx_readable_reg,
656 	.volatile_reg = stm32_spdifrx_volatile_reg,
657 	.writeable_reg = stm32_spdifrx_writeable_reg,
658 	.num_reg_defaults_raw = STM32_SPDIFRX_SIDR / sizeof(u32) + 1,
659 	.fast_io = true,
660 	.cache_type = REGCACHE_FLAT,
661 };
662 
663 static irqreturn_t stm32_spdifrx_isr(int irq, void *devid)
664 {
665 	struct stm32_spdifrx_data *spdifrx = (struct stm32_spdifrx_data *)devid;
666 	struct snd_pcm_substream *substream = spdifrx->substream;
667 	struct platform_device *pdev = spdifrx->pdev;
668 	unsigned int cr, mask, sr, imr;
669 	unsigned int flags;
670 	int err = 0, err_xrun = 0;
671 
672 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_SR, &sr);
673 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_IMR, &imr);
674 
675 	mask = imr & SPDIFRX_XIMR_MASK;
676 	/* SERR, TERR, FERR IRQs are generated if IFEIE is set */
677 	if (mask & SPDIFRX_IMR_IFEIE)
678 		mask |= (SPDIFRX_IMR_IFEIE << 1) | (SPDIFRX_IMR_IFEIE << 2);
679 
680 	flags = sr & mask;
681 	if (!flags) {
682 		dev_err(&pdev->dev, "Unexpected IRQ. rflags=%#x, imr=%#x\n",
683 			sr, imr);
684 		return IRQ_NONE;
685 	}
686 
687 	/* Clear IRQs */
688 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IFCR,
689 			   SPDIFRX_XIFCR_MASK, flags);
690 
691 	if (flags & SPDIFRX_SR_PERR) {
692 		dev_dbg(&pdev->dev, "Parity error\n");
693 		err_xrun = 1;
694 	}
695 
696 	if (flags & SPDIFRX_SR_OVR) {
697 		dev_dbg(&pdev->dev, "Overrun error\n");
698 		err_xrun = 1;
699 	}
700 
701 	if (flags & SPDIFRX_SR_SBD)
702 		dev_dbg(&pdev->dev, "Synchronization block detected\n");
703 
704 	if (flags & SPDIFRX_SR_SYNCD) {
705 		dev_dbg(&pdev->dev, "Synchronization done\n");
706 
707 		/* Enable spdifrx */
708 		cr = SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_ENABLE);
709 		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
710 				   SPDIFRX_CR_SPDIFEN_MASK, cr);
711 	}
712 
713 	if (flags & SPDIFRX_SR_FERR) {
714 		dev_dbg(&pdev->dev, "Frame error\n");
715 		err = 1;
716 	}
717 
718 	if (flags & SPDIFRX_SR_SERR) {
719 		dev_dbg(&pdev->dev, "Synchronization error\n");
720 		err = 1;
721 	}
722 
723 	if (flags & SPDIFRX_SR_TERR) {
724 		dev_dbg(&pdev->dev, "Timeout error\n");
725 		err = 1;
726 	}
727 
728 	if (err) {
729 		/* SPDIFRX in STATE_STOP. Disable SPDIFRX to clear errors */
730 		cr = SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_DISABLE);
731 		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
732 				   SPDIFRX_CR_SPDIFEN_MASK, cr);
733 
734 		if (substream)
735 			snd_pcm_stop(substream, SNDRV_PCM_STATE_DISCONNECTED);
736 
737 		return IRQ_HANDLED;
738 	}
739 
740 	if (err_xrun && substream)
741 		snd_pcm_stop_xrun(substream);
742 
743 	return IRQ_HANDLED;
744 }
745 
746 static int stm32_spdifrx_startup(struct snd_pcm_substream *substream,
747 				 struct snd_soc_dai *cpu_dai)
748 {
749 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
750 	int ret;
751 
752 	spdifrx->substream = substream;
753 
754 	ret = clk_prepare_enable(spdifrx->kclk);
755 	if (ret)
756 		dev_err(&spdifrx->pdev->dev, "Enable kclk failed: %d\n", ret);
757 
758 	return ret;
759 }
760 
761 static int stm32_spdifrx_hw_params(struct snd_pcm_substream *substream,
762 				   struct snd_pcm_hw_params *params,
763 				   struct snd_soc_dai *cpu_dai)
764 {
765 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
766 	int data_size = params_width(params);
767 	int fmt;
768 
769 	switch (data_size) {
770 	case 16:
771 		fmt = SPDIFRX_DRFMT_PACKED;
772 		break;
773 	case 32:
774 		fmt = SPDIFRX_DRFMT_LEFT;
775 		break;
776 	default:
777 		dev_err(&spdifrx->pdev->dev, "Unexpected data format\n");
778 		return -EINVAL;
779 	}
780 
781 	/*
782 	 * Set buswidth to 4 bytes for all data formats.
783 	 * Packed format: transfer 2 x 2 bytes samples
784 	 * Left format: transfer 1 x 3 bytes samples + 1 dummy byte
785 	 */
786 	spdifrx->dma_params.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
787 	snd_soc_dai_init_dma_data(cpu_dai, NULL, &spdifrx->dma_params);
788 
789 	return regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
790 				  SPDIFRX_CR_DRFMT_MASK,
791 				  SPDIFRX_CR_DRFMTSET(fmt));
792 }
793 
794 static int stm32_spdifrx_trigger(struct snd_pcm_substream *substream, int cmd,
795 				 struct snd_soc_dai *cpu_dai)
796 {
797 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
798 	int ret = 0;
799 
800 	switch (cmd) {
801 	case SNDRV_PCM_TRIGGER_START:
802 	case SNDRV_PCM_TRIGGER_RESUME:
803 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
804 		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IMR,
805 				   SPDIFRX_IMR_OVRIE, SPDIFRX_IMR_OVRIE);
806 
807 		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
808 				   SPDIFRX_CR_RXDMAEN, SPDIFRX_CR_RXDMAEN);
809 
810 		ret = stm32_spdifrx_start_sync(spdifrx);
811 		break;
812 	case SNDRV_PCM_TRIGGER_SUSPEND:
813 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
814 	case SNDRV_PCM_TRIGGER_STOP:
815 		stm32_spdifrx_stop(spdifrx);
816 		break;
817 	default:
818 		return -EINVAL;
819 	}
820 
821 	return ret;
822 }
823 
824 static void stm32_spdifrx_shutdown(struct snd_pcm_substream *substream,
825 				   struct snd_soc_dai *cpu_dai)
826 {
827 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
828 
829 	spdifrx->substream = NULL;
830 	clk_disable_unprepare(spdifrx->kclk);
831 }
832 
833 static const struct snd_soc_dai_ops stm32_spdifrx_pcm_dai_ops = {
834 	.startup	= stm32_spdifrx_startup,
835 	.hw_params	= stm32_spdifrx_hw_params,
836 	.trigger	= stm32_spdifrx_trigger,
837 	.shutdown	= stm32_spdifrx_shutdown,
838 };
839 
840 static struct snd_soc_dai_driver stm32_spdifrx_dai[] = {
841 	{
842 		.probe = stm32_spdifrx_dai_probe,
843 		.capture = {
844 			.stream_name = "CPU-Capture",
845 			.channels_min = 1,
846 			.channels_max = 2,
847 			.rates = SNDRV_PCM_RATE_8000_192000,
848 			.formats = SNDRV_PCM_FMTBIT_S32_LE |
849 				   SNDRV_PCM_FMTBIT_S16_LE,
850 		},
851 		.ops = &stm32_spdifrx_pcm_dai_ops,
852 	}
853 };
854 
855 static const struct snd_pcm_hardware stm32_spdifrx_pcm_hw = {
856 	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_MMAP,
857 	.buffer_bytes_max = 8 * PAGE_SIZE,
858 	.period_bytes_min = 1024,
859 	.period_bytes_max = 4 * PAGE_SIZE,
860 	.periods_min = 2,
861 	.periods_max = 8,
862 };
863 
864 static const struct snd_soc_component_driver stm32_spdifrx_component = {
865 	.name = "stm32-spdifrx",
866 };
867 
868 static const struct snd_dmaengine_pcm_config stm32_spdifrx_pcm_config = {
869 	.pcm_hardware = &stm32_spdifrx_pcm_hw,
870 	.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
871 };
872 
873 static const struct of_device_id stm32_spdifrx_ids[] = {
874 	{
875 		.compatible = "st,stm32h7-spdifrx",
876 		.data = &stm32_h7_spdifrx_regmap_conf
877 	},
878 	{}
879 };
880 
881 static int stm32_spdifrx_parse_of(struct platform_device *pdev,
882 				  struct stm32_spdifrx_data *spdifrx)
883 {
884 	struct device_node *np = pdev->dev.of_node;
885 	const struct of_device_id *of_id;
886 	struct resource *res;
887 
888 	if (!np)
889 		return -ENODEV;
890 
891 	of_id = of_match_device(stm32_spdifrx_ids, &pdev->dev);
892 	if (of_id)
893 		spdifrx->regmap_conf =
894 			(const struct regmap_config *)of_id->data;
895 	else
896 		return -EINVAL;
897 
898 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
899 	spdifrx->base = devm_ioremap_resource(&pdev->dev, res);
900 	if (IS_ERR(spdifrx->base))
901 		return PTR_ERR(spdifrx->base);
902 
903 	spdifrx->phys_addr = res->start;
904 
905 	spdifrx->kclk = devm_clk_get(&pdev->dev, "kclk");
906 	if (IS_ERR(spdifrx->kclk)) {
907 		dev_err(&pdev->dev, "Could not get kclk\n");
908 		return PTR_ERR(spdifrx->kclk);
909 	}
910 
911 	spdifrx->irq = platform_get_irq(pdev, 0);
912 	if (spdifrx->irq < 0)
913 		return spdifrx->irq;
914 
915 	return 0;
916 }
917 
918 static int stm32_spdifrx_probe(struct platform_device *pdev)
919 {
920 	struct stm32_spdifrx_data *spdifrx;
921 	struct reset_control *rst;
922 	const struct snd_dmaengine_pcm_config *pcm_config = NULL;
923 	u32 ver, idr;
924 	int ret;
925 
926 	spdifrx = devm_kzalloc(&pdev->dev, sizeof(*spdifrx), GFP_KERNEL);
927 	if (!spdifrx)
928 		return -ENOMEM;
929 
930 	spdifrx->pdev = pdev;
931 	init_completion(&spdifrx->cs_completion);
932 	spin_lock_init(&spdifrx->lock);
933 
934 	platform_set_drvdata(pdev, spdifrx);
935 
936 	ret = stm32_spdifrx_parse_of(pdev, spdifrx);
937 	if (ret)
938 		return ret;
939 
940 	spdifrx->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "kclk",
941 						    spdifrx->base,
942 						    spdifrx->regmap_conf);
943 	if (IS_ERR(spdifrx->regmap)) {
944 		dev_err(&pdev->dev, "Regmap init failed\n");
945 		return PTR_ERR(spdifrx->regmap);
946 	}
947 
948 	ret = devm_request_irq(&pdev->dev, spdifrx->irq, stm32_spdifrx_isr, 0,
949 			       dev_name(&pdev->dev), spdifrx);
950 	if (ret) {
951 		dev_err(&pdev->dev, "IRQ request returned %d\n", ret);
952 		return ret;
953 	}
954 
955 	rst = devm_reset_control_get_exclusive(&pdev->dev, NULL);
956 	if (!IS_ERR(rst)) {
957 		reset_control_assert(rst);
958 		udelay(2);
959 		reset_control_deassert(rst);
960 	}
961 
962 	ret = devm_snd_soc_register_component(&pdev->dev,
963 					      &stm32_spdifrx_component,
964 					      stm32_spdifrx_dai,
965 					      ARRAY_SIZE(stm32_spdifrx_dai));
966 	if (ret)
967 		return ret;
968 
969 	ret = stm32_spdifrx_dma_ctrl_register(&pdev->dev, spdifrx);
970 	if (ret)
971 		goto error;
972 
973 	pcm_config = &stm32_spdifrx_pcm_config;
974 	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, pcm_config, 0);
975 	if (ret) {
976 		dev_err(&pdev->dev, "PCM DMA register returned %d\n", ret);
977 		goto error;
978 	}
979 
980 	ret = regmap_read(spdifrx->regmap, STM32_SPDIFRX_IDR, &idr);
981 	if (ret)
982 		goto error;
983 
984 	if (idr == SPDIFRX_IPIDR_NUMBER) {
985 		ret = regmap_read(spdifrx->regmap, STM32_SPDIFRX_VERR, &ver);
986 
987 		dev_dbg(&pdev->dev, "SPDIFRX version: %lu.%lu registered\n",
988 			FIELD_GET(SPDIFRX_VERR_MAJ_MASK, ver),
989 			FIELD_GET(SPDIFRX_VERR_MIN_MASK, ver));
990 	}
991 
992 	return ret;
993 
994 error:
995 	if (!IS_ERR(spdifrx->ctrl_chan))
996 		dma_release_channel(spdifrx->ctrl_chan);
997 	if (spdifrx->dmab)
998 		snd_dma_free_pages(spdifrx->dmab);
999 
1000 	return ret;
1001 }
1002 
1003 static int stm32_spdifrx_remove(struct platform_device *pdev)
1004 {
1005 	struct stm32_spdifrx_data *spdifrx = platform_get_drvdata(pdev);
1006 
1007 	if (spdifrx->ctrl_chan)
1008 		dma_release_channel(spdifrx->ctrl_chan);
1009 
1010 	if (spdifrx->dmab)
1011 		snd_dma_free_pages(spdifrx->dmab);
1012 
1013 	return 0;
1014 }
1015 
1016 MODULE_DEVICE_TABLE(of, stm32_spdifrx_ids);
1017 
1018 #ifdef CONFIG_PM_SLEEP
1019 static int stm32_spdifrx_suspend(struct device *dev)
1020 {
1021 	struct stm32_spdifrx_data *spdifrx = dev_get_drvdata(dev);
1022 
1023 	regcache_cache_only(spdifrx->regmap, true);
1024 	regcache_mark_dirty(spdifrx->regmap);
1025 
1026 	return 0;
1027 }
1028 
1029 static int stm32_spdifrx_resume(struct device *dev)
1030 {
1031 	struct stm32_spdifrx_data *spdifrx = dev_get_drvdata(dev);
1032 
1033 	regcache_cache_only(spdifrx->regmap, false);
1034 
1035 	return regcache_sync(spdifrx->regmap);
1036 }
1037 #endif /* CONFIG_PM_SLEEP */
1038 
1039 static const struct dev_pm_ops stm32_spdifrx_pm_ops = {
1040 	SET_SYSTEM_SLEEP_PM_OPS(stm32_spdifrx_suspend, stm32_spdifrx_resume)
1041 };
1042 
1043 static struct platform_driver stm32_spdifrx_driver = {
1044 	.driver = {
1045 		.name = "st,stm32-spdifrx",
1046 		.of_match_table = stm32_spdifrx_ids,
1047 		.pm = &stm32_spdifrx_pm_ops,
1048 	},
1049 	.probe = stm32_spdifrx_probe,
1050 	.remove = stm32_spdifrx_remove,
1051 };
1052 
1053 module_platform_driver(stm32_spdifrx_driver);
1054 
1055 MODULE_DESCRIPTION("STM32 Soc spdifrx Interface");
1056 MODULE_AUTHOR("Olivier Moysan, <olivier.moysan@st.com>");
1057 MODULE_ALIAS("platform:stm32-spdifrx");
1058 MODULE_LICENSE("GPL v2");
1059