xref: /openbmc/linux/sound/soc/stm/stm32_spdifrx.c (revision 3ddc8b84)
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/pm_runtime.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  * @irq_lock: prevent race condition with IRQ on stream state
224  * @cs: channel status buffer
225  * @ub: user data buffer
226  * @irq: SPDIFRX interrupt line
227  * @refcount: keep count of opened DMA channels
228  */
229 struct stm32_spdifrx_data {
230 	struct platform_device *pdev;
231 	void __iomem *base;
232 	struct regmap *regmap;
233 	const struct regmap_config *regmap_conf;
234 	struct completion cs_completion;
235 	struct clk *kclk;
236 	struct snd_dmaengine_dai_dma_data dma_params;
237 	struct snd_pcm_substream *substream;
238 	struct snd_dma_buffer *dmab;
239 	struct dma_chan *ctrl_chan;
240 	struct dma_async_tx_descriptor *desc;
241 	struct dma_slave_config slave_config;
242 	dma_addr_t phys_addr;
243 	spinlock_t lock;  /* Sync enabling lock */
244 	spinlock_t irq_lock; /* Prevent race condition on stream state */
245 	unsigned char cs[SPDIFRX_CS_BYTES_NB];
246 	unsigned char ub[SPDIFRX_UB_BYTES_NB];
247 	int irq;
248 	int refcount;
249 };
250 
251 static void stm32_spdifrx_dma_complete(void *data)
252 {
253 	struct stm32_spdifrx_data *spdifrx = (struct stm32_spdifrx_data *)data;
254 	struct platform_device *pdev = spdifrx->pdev;
255 	u32 *p_start = (u32 *)spdifrx->dmab->area;
256 	u32 *p_end = p_start + (2 * SPDIFRX_CS_BYTES_NB) - 1;
257 	u32 *ptr = p_start;
258 	u16 *ub_ptr = (short *)spdifrx->ub;
259 	int i = 0;
260 
261 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
262 			   SPDIFRX_CR_CBDMAEN,
263 			   (unsigned int)~SPDIFRX_CR_CBDMAEN);
264 
265 	if (!spdifrx->dmab->area)
266 		return;
267 
268 	while (ptr <= p_end) {
269 		if (*ptr & SPDIFRX_CSR_SOB)
270 			break;
271 		ptr++;
272 	}
273 
274 	if (ptr > p_end) {
275 		dev_err(&pdev->dev, "Start of S/PDIF block not found\n");
276 		return;
277 	}
278 
279 	while (i < SPDIFRX_CS_BYTES_NB) {
280 		spdifrx->cs[i] = (unsigned char)SPDIFRX_CSR_CSGET(*ptr);
281 		*ub_ptr++ = SPDIFRX_CSR_USRGET(*ptr++);
282 		if (ptr > p_end) {
283 			dev_err(&pdev->dev, "Failed to get channel status\n");
284 			return;
285 		}
286 		i++;
287 	}
288 
289 	complete(&spdifrx->cs_completion);
290 }
291 
292 static int stm32_spdifrx_dma_ctrl_start(struct stm32_spdifrx_data *spdifrx)
293 {
294 	dma_cookie_t cookie;
295 	int err;
296 
297 	spdifrx->desc = dmaengine_prep_slave_single(spdifrx->ctrl_chan,
298 						    spdifrx->dmab->addr,
299 						    SPDIFRX_CSR_BUF_LENGTH,
300 						    DMA_DEV_TO_MEM,
301 						    DMA_CTRL_ACK);
302 	if (!spdifrx->desc)
303 		return -EINVAL;
304 
305 	spdifrx->desc->callback = stm32_spdifrx_dma_complete;
306 	spdifrx->desc->callback_param = spdifrx;
307 	cookie = dmaengine_submit(spdifrx->desc);
308 	err = dma_submit_error(cookie);
309 	if (err)
310 		return -EINVAL;
311 
312 	dma_async_issue_pending(spdifrx->ctrl_chan);
313 
314 	return 0;
315 }
316 
317 static void stm32_spdifrx_dma_ctrl_stop(struct stm32_spdifrx_data *spdifrx)
318 {
319 	dmaengine_terminate_async(spdifrx->ctrl_chan);
320 }
321 
322 static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
323 {
324 	int cr, cr_mask, imr, ret;
325 	unsigned long flags;
326 
327 	/* Enable IRQs */
328 	imr = SPDIFRX_IMR_IFEIE | SPDIFRX_IMR_SYNCDIE | SPDIFRX_IMR_PERRIE;
329 	ret = regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IMR, imr, imr);
330 	if (ret)
331 		return ret;
332 
333 	spin_lock_irqsave(&spdifrx->lock, flags);
334 
335 	spdifrx->refcount++;
336 
337 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_CR, &cr);
338 
339 	if (!(cr & SPDIFRX_CR_SPDIFEN_MASK)) {
340 		/*
341 		 * Start sync if SPDIFRX is still in idle state.
342 		 * SPDIFRX reception enabled when sync done
343 		 */
344 		dev_dbg(&spdifrx->pdev->dev, "start synchronization\n");
345 
346 		/*
347 		 * SPDIFRX configuration:
348 		 * Wait for activity before starting sync process. This avoid
349 		 * to issue sync errors when spdif signal is missing on input.
350 		 * Preamble, CS, user, validity and parity error bits not copied
351 		 * to DR register.
352 		 */
353 		cr = SPDIFRX_CR_WFA | SPDIFRX_CR_PMSK | SPDIFRX_CR_VMSK |
354 		     SPDIFRX_CR_CUMSK | SPDIFRX_CR_PTMSK | SPDIFRX_CR_RXSTEO;
355 		cr_mask = cr;
356 
357 		cr |= SPDIFRX_CR_NBTRSET(SPDIFRX_NBTR_63);
358 		cr_mask |= SPDIFRX_CR_NBTR_MASK;
359 		cr |= SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_SYNC);
360 		cr_mask |= SPDIFRX_CR_SPDIFEN_MASK;
361 		ret = regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
362 					 cr_mask, cr);
363 		if (ret < 0)
364 			dev_err(&spdifrx->pdev->dev,
365 				"Failed to start synchronization\n");
366 	}
367 
368 	spin_unlock_irqrestore(&spdifrx->lock, flags);
369 
370 	return ret;
371 }
372 
373 static void stm32_spdifrx_stop(struct stm32_spdifrx_data *spdifrx)
374 {
375 	int cr, cr_mask, reg;
376 	unsigned long flags;
377 
378 	spin_lock_irqsave(&spdifrx->lock, flags);
379 
380 	if (--spdifrx->refcount) {
381 		spin_unlock_irqrestore(&spdifrx->lock, flags);
382 		return;
383 	}
384 
385 	cr = SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_DISABLE);
386 	cr_mask = SPDIFRX_CR_SPDIFEN_MASK | SPDIFRX_CR_RXDMAEN;
387 
388 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR, cr_mask, cr);
389 
390 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IMR,
391 			   SPDIFRX_XIMR_MASK, 0);
392 
393 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IFCR,
394 			   SPDIFRX_XIFCR_MASK, SPDIFRX_XIFCR_MASK);
395 
396 	/* dummy read to clear CSRNE and RXNE in status register */
397 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_DR, &reg);
398 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_CSR, &reg);
399 
400 	spin_unlock_irqrestore(&spdifrx->lock, flags);
401 }
402 
403 static int stm32_spdifrx_dma_ctrl_register(struct device *dev,
404 					   struct stm32_spdifrx_data *spdifrx)
405 {
406 	int ret;
407 
408 	spdifrx->ctrl_chan = dma_request_chan(dev, "rx-ctrl");
409 	if (IS_ERR(spdifrx->ctrl_chan))
410 		return dev_err_probe(dev, PTR_ERR(spdifrx->ctrl_chan),
411 				     "dma_request_slave_channel error\n");
412 
413 	spdifrx->dmab = devm_kzalloc(dev, sizeof(struct snd_dma_buffer),
414 				     GFP_KERNEL);
415 	if (!spdifrx->dmab)
416 		return -ENOMEM;
417 
418 	spdifrx->dmab->dev.type = SNDRV_DMA_TYPE_DEV_IRAM;
419 	spdifrx->dmab->dev.dev = dev;
420 	ret = snd_dma_alloc_pages(spdifrx->dmab->dev.type, dev,
421 				  SPDIFRX_CSR_BUF_LENGTH, spdifrx->dmab);
422 	if (ret < 0) {
423 		dev_err(dev, "snd_dma_alloc_pages returned error %d\n", ret);
424 		return ret;
425 	}
426 
427 	spdifrx->slave_config.direction = DMA_DEV_TO_MEM;
428 	spdifrx->slave_config.src_addr = (dma_addr_t)(spdifrx->phys_addr +
429 					 STM32_SPDIFRX_CSR);
430 	spdifrx->slave_config.dst_addr = spdifrx->dmab->addr;
431 	spdifrx->slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
432 	spdifrx->slave_config.src_maxburst = 1;
433 
434 	ret = dmaengine_slave_config(spdifrx->ctrl_chan,
435 				     &spdifrx->slave_config);
436 	if (ret < 0) {
437 		dev_err(dev, "dmaengine_slave_config returned error %d\n", ret);
438 		spdifrx->ctrl_chan = NULL;
439 	}
440 
441 	return ret;
442 };
443 
444 static const char * const spdifrx_enum_input[] = {
445 	"in0", "in1", "in2", "in3"
446 };
447 
448 /*  By default CS bits are retrieved from channel A */
449 static const char * const spdifrx_enum_cs_channel[] = {
450 	"A", "B"
451 };
452 
453 static SOC_ENUM_SINGLE_DECL(ctrl_enum_input,
454 			    STM32_SPDIFRX_CR, SPDIFRX_CR_INSEL_SHIFT,
455 			    spdifrx_enum_input);
456 
457 static SOC_ENUM_SINGLE_DECL(ctrl_enum_cs_channel,
458 			    STM32_SPDIFRX_CR, SPDIFRX_CR_CHSEL_SHIFT,
459 			    spdifrx_enum_cs_channel);
460 
461 static int stm32_spdifrx_info(struct snd_kcontrol *kcontrol,
462 			      struct snd_ctl_elem_info *uinfo)
463 {
464 	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
465 	uinfo->count = 1;
466 
467 	return 0;
468 }
469 
470 static int stm32_spdifrx_ub_info(struct snd_kcontrol *kcontrol,
471 				 struct snd_ctl_elem_info *uinfo)
472 {
473 	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
474 	uinfo->count = 1;
475 
476 	return 0;
477 }
478 
479 static int stm32_spdifrx_get_ctrl_data(struct stm32_spdifrx_data *spdifrx)
480 {
481 	int ret = 0;
482 
483 	memset(spdifrx->cs, 0, SPDIFRX_CS_BYTES_NB);
484 	memset(spdifrx->ub, 0, SPDIFRX_UB_BYTES_NB);
485 
486 	ret = stm32_spdifrx_dma_ctrl_start(spdifrx);
487 	if (ret < 0)
488 		return ret;
489 
490 	ret = clk_prepare_enable(spdifrx->kclk);
491 	if (ret) {
492 		dev_err(&spdifrx->pdev->dev, "Enable kclk failed: %d\n", ret);
493 		return ret;
494 	}
495 
496 	ret = regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
497 				 SPDIFRX_CR_CBDMAEN, SPDIFRX_CR_CBDMAEN);
498 	if (ret < 0)
499 		goto end;
500 
501 	ret = stm32_spdifrx_start_sync(spdifrx);
502 	if (ret < 0)
503 		goto end;
504 
505 	if (wait_for_completion_interruptible_timeout(&spdifrx->cs_completion,
506 						      msecs_to_jiffies(100))
507 						      <= 0) {
508 		dev_dbg(&spdifrx->pdev->dev, "Failed to get control data\n");
509 		ret = -EAGAIN;
510 	}
511 
512 	stm32_spdifrx_stop(spdifrx);
513 	stm32_spdifrx_dma_ctrl_stop(spdifrx);
514 
515 end:
516 	clk_disable_unprepare(spdifrx->kclk);
517 
518 	return ret;
519 }
520 
521 static int stm32_spdifrx_capture_get(struct snd_kcontrol *kcontrol,
522 				     struct snd_ctl_elem_value *ucontrol)
523 {
524 	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
525 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
526 
527 	stm32_spdifrx_get_ctrl_data(spdifrx);
528 
529 	ucontrol->value.iec958.status[0] = spdifrx->cs[0];
530 	ucontrol->value.iec958.status[1] = spdifrx->cs[1];
531 	ucontrol->value.iec958.status[2] = spdifrx->cs[2];
532 	ucontrol->value.iec958.status[3] = spdifrx->cs[3];
533 	ucontrol->value.iec958.status[4] = spdifrx->cs[4];
534 
535 	return 0;
536 }
537 
538 static int stm32_spdif_user_bits_get(struct snd_kcontrol *kcontrol,
539 				     struct snd_ctl_elem_value *ucontrol)
540 {
541 	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
542 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
543 
544 	stm32_spdifrx_get_ctrl_data(spdifrx);
545 
546 	ucontrol->value.iec958.status[0] = spdifrx->ub[0];
547 	ucontrol->value.iec958.status[1] = spdifrx->ub[1];
548 	ucontrol->value.iec958.status[2] = spdifrx->ub[2];
549 	ucontrol->value.iec958.status[3] = spdifrx->ub[3];
550 	ucontrol->value.iec958.status[4] = spdifrx->ub[4];
551 
552 	return 0;
553 }
554 
555 static struct snd_kcontrol_new stm32_spdifrx_iec_ctrls[] = {
556 	/* Channel status control */
557 	{
558 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
559 		.name = SNDRV_CTL_NAME_IEC958("", CAPTURE, DEFAULT),
560 		.access = SNDRV_CTL_ELEM_ACCESS_READ |
561 			  SNDRV_CTL_ELEM_ACCESS_VOLATILE,
562 		.info = stm32_spdifrx_info,
563 		.get = stm32_spdifrx_capture_get,
564 	},
565 	/* User bits control */
566 	{
567 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
568 		.name = "IEC958 User Bit Capture Default",
569 		.access = SNDRV_CTL_ELEM_ACCESS_READ |
570 			  SNDRV_CTL_ELEM_ACCESS_VOLATILE,
571 		.info = stm32_spdifrx_ub_info,
572 		.get = stm32_spdif_user_bits_get,
573 	},
574 };
575 
576 static struct snd_kcontrol_new stm32_spdifrx_ctrls[] = {
577 	SOC_ENUM("SPDIFRX input", ctrl_enum_input),
578 	SOC_ENUM("SPDIFRX CS channel", ctrl_enum_cs_channel),
579 };
580 
581 static int stm32_spdifrx_dai_register_ctrls(struct snd_soc_dai *cpu_dai)
582 {
583 	int ret;
584 
585 	ret = snd_soc_add_dai_controls(cpu_dai, stm32_spdifrx_iec_ctrls,
586 				       ARRAY_SIZE(stm32_spdifrx_iec_ctrls));
587 	if (ret < 0)
588 		return ret;
589 
590 	return snd_soc_add_component_controls(cpu_dai->component,
591 					      stm32_spdifrx_ctrls,
592 					      ARRAY_SIZE(stm32_spdifrx_ctrls));
593 }
594 
595 static int stm32_spdifrx_dai_probe(struct snd_soc_dai *cpu_dai)
596 {
597 	struct stm32_spdifrx_data *spdifrx = dev_get_drvdata(cpu_dai->dev);
598 
599 	spdifrx->dma_params.addr = (dma_addr_t)(spdifrx->phys_addr +
600 				   STM32_SPDIFRX_DR);
601 	spdifrx->dma_params.maxburst = 1;
602 
603 	snd_soc_dai_init_dma_data(cpu_dai, NULL, &spdifrx->dma_params);
604 
605 	return stm32_spdifrx_dai_register_ctrls(cpu_dai);
606 }
607 
608 static bool stm32_spdifrx_readable_reg(struct device *dev, unsigned int reg)
609 {
610 	switch (reg) {
611 	case STM32_SPDIFRX_CR:
612 	case STM32_SPDIFRX_IMR:
613 	case STM32_SPDIFRX_SR:
614 	case STM32_SPDIFRX_IFCR:
615 	case STM32_SPDIFRX_DR:
616 	case STM32_SPDIFRX_CSR:
617 	case STM32_SPDIFRX_DIR:
618 	case STM32_SPDIFRX_VERR:
619 	case STM32_SPDIFRX_IDR:
620 	case STM32_SPDIFRX_SIDR:
621 		return true;
622 	default:
623 		return false;
624 	}
625 }
626 
627 static bool stm32_spdifrx_volatile_reg(struct device *dev, unsigned int reg)
628 {
629 	switch (reg) {
630 	case STM32_SPDIFRX_DR:
631 	case STM32_SPDIFRX_CSR:
632 	case STM32_SPDIFRX_SR:
633 	case STM32_SPDIFRX_DIR:
634 		return true;
635 	default:
636 		return false;
637 	}
638 }
639 
640 static bool stm32_spdifrx_writeable_reg(struct device *dev, unsigned int reg)
641 {
642 	switch (reg) {
643 	case STM32_SPDIFRX_CR:
644 	case STM32_SPDIFRX_IMR:
645 	case STM32_SPDIFRX_IFCR:
646 		return true;
647 	default:
648 		return false;
649 	}
650 }
651 
652 static const struct regmap_config stm32_h7_spdifrx_regmap_conf = {
653 	.reg_bits = 32,
654 	.reg_stride = 4,
655 	.val_bits = 32,
656 	.max_register = STM32_SPDIFRX_SIDR,
657 	.readable_reg = stm32_spdifrx_readable_reg,
658 	.volatile_reg = stm32_spdifrx_volatile_reg,
659 	.writeable_reg = stm32_spdifrx_writeable_reg,
660 	.num_reg_defaults_raw = STM32_SPDIFRX_SIDR / sizeof(u32) + 1,
661 	.fast_io = true,
662 	.cache_type = REGCACHE_FLAT,
663 };
664 
665 static irqreturn_t stm32_spdifrx_isr(int irq, void *devid)
666 {
667 	struct stm32_spdifrx_data *spdifrx = (struct stm32_spdifrx_data *)devid;
668 	struct platform_device *pdev = spdifrx->pdev;
669 	unsigned int cr, mask, sr, imr;
670 	unsigned int flags, sync_state;
671 	int err = 0, err_xrun = 0;
672 
673 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_SR, &sr);
674 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_IMR, &imr);
675 
676 	mask = imr & SPDIFRX_XIMR_MASK;
677 	/* SERR, TERR, FERR IRQs are generated if IFEIE is set */
678 	if (mask & SPDIFRX_IMR_IFEIE)
679 		mask |= (SPDIFRX_IMR_IFEIE << 1) | (SPDIFRX_IMR_IFEIE << 2);
680 
681 	flags = sr & mask;
682 	if (!flags) {
683 		dev_err(&pdev->dev, "Unexpected IRQ. rflags=%#x, imr=%#x\n",
684 			sr, imr);
685 		return IRQ_NONE;
686 	}
687 
688 	/* Clear IRQs */
689 	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IFCR,
690 			   SPDIFRX_XIFCR_MASK, flags);
691 
692 	if (flags & SPDIFRX_SR_PERR) {
693 		dev_dbg(&pdev->dev, "Parity error\n");
694 		err_xrun = 1;
695 	}
696 
697 	if (flags & SPDIFRX_SR_OVR) {
698 		dev_dbg(&pdev->dev, "Overrun error\n");
699 		err_xrun = 1;
700 	}
701 
702 	if (flags & SPDIFRX_SR_SBD)
703 		dev_dbg(&pdev->dev, "Synchronization block detected\n");
704 
705 	if (flags & SPDIFRX_SR_SYNCD) {
706 		dev_dbg(&pdev->dev, "Synchronization done\n");
707 
708 		/* Enable spdifrx */
709 		cr = SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_ENABLE);
710 		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
711 				   SPDIFRX_CR_SPDIFEN_MASK, cr);
712 	}
713 
714 	if (flags & SPDIFRX_SR_FERR) {
715 		dev_dbg(&pdev->dev, "Frame error\n");
716 		err = 1;
717 	}
718 
719 	if (flags & SPDIFRX_SR_SERR) {
720 		dev_dbg(&pdev->dev, "Synchronization error\n");
721 		err = 1;
722 	}
723 
724 	if (flags & SPDIFRX_SR_TERR) {
725 		dev_dbg(&pdev->dev, "Timeout error\n");
726 		err = 1;
727 	}
728 
729 	if (err) {
730 		regmap_read(spdifrx->regmap, STM32_SPDIFRX_CR, &cr);
731 		sync_state = FIELD_GET(SPDIFRX_CR_SPDIFEN_MASK, cr) &&
732 			     SPDIFRX_SPDIFEN_SYNC;
733 
734 		/* SPDIFRX is in STATE_STOP. Disable SPDIFRX to clear errors */
735 		cr = SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_DISABLE);
736 		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
737 				   SPDIFRX_CR_SPDIFEN_MASK, cr);
738 
739 		/* If SPDIFRX was in STATE_SYNC, retry synchro */
740 		if (sync_state) {
741 			cr = SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_SYNC);
742 			regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
743 					   SPDIFRX_CR_SPDIFEN_MASK, cr);
744 			return IRQ_HANDLED;
745 		}
746 
747 		spin_lock(&spdifrx->irq_lock);
748 		if (spdifrx->substream)
749 			snd_pcm_stop(spdifrx->substream,
750 				     SNDRV_PCM_STATE_DISCONNECTED);
751 		spin_unlock(&spdifrx->irq_lock);
752 
753 		return IRQ_HANDLED;
754 	}
755 
756 	spin_lock(&spdifrx->irq_lock);
757 	if (err_xrun && spdifrx->substream)
758 		snd_pcm_stop_xrun(spdifrx->substream);
759 	spin_unlock(&spdifrx->irq_lock);
760 
761 	return IRQ_HANDLED;
762 }
763 
764 static int stm32_spdifrx_startup(struct snd_pcm_substream *substream,
765 				 struct snd_soc_dai *cpu_dai)
766 {
767 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
768 	unsigned long flags;
769 	int ret;
770 
771 	spin_lock_irqsave(&spdifrx->irq_lock, flags);
772 	spdifrx->substream = substream;
773 	spin_unlock_irqrestore(&spdifrx->irq_lock, flags);
774 
775 	ret = clk_prepare_enable(spdifrx->kclk);
776 	if (ret)
777 		dev_err(&spdifrx->pdev->dev, "Enable kclk failed: %d\n", ret);
778 
779 	return ret;
780 }
781 
782 static int stm32_spdifrx_hw_params(struct snd_pcm_substream *substream,
783 				   struct snd_pcm_hw_params *params,
784 				   struct snd_soc_dai *cpu_dai)
785 {
786 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
787 	int data_size = params_width(params);
788 	int fmt;
789 
790 	switch (data_size) {
791 	case 16:
792 		fmt = SPDIFRX_DRFMT_PACKED;
793 		break;
794 	case 32:
795 		fmt = SPDIFRX_DRFMT_LEFT;
796 		break;
797 	default:
798 		dev_err(&spdifrx->pdev->dev, "Unexpected data format\n");
799 		return -EINVAL;
800 	}
801 
802 	/*
803 	 * Set buswidth to 4 bytes for all data formats.
804 	 * Packed format: transfer 2 x 2 bytes samples
805 	 * Left format: transfer 1 x 3 bytes samples + 1 dummy byte
806 	 */
807 	spdifrx->dma_params.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
808 	snd_soc_dai_init_dma_data(cpu_dai, NULL, &spdifrx->dma_params);
809 
810 	return regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
811 				  SPDIFRX_CR_DRFMT_MASK,
812 				  SPDIFRX_CR_DRFMTSET(fmt));
813 }
814 
815 static int stm32_spdifrx_trigger(struct snd_pcm_substream *substream, int cmd,
816 				 struct snd_soc_dai *cpu_dai)
817 {
818 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
819 	int ret = 0;
820 
821 	switch (cmd) {
822 	case SNDRV_PCM_TRIGGER_START:
823 	case SNDRV_PCM_TRIGGER_RESUME:
824 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
825 		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IMR,
826 				   SPDIFRX_IMR_OVRIE, SPDIFRX_IMR_OVRIE);
827 
828 		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
829 				   SPDIFRX_CR_RXDMAEN, SPDIFRX_CR_RXDMAEN);
830 
831 		ret = stm32_spdifrx_start_sync(spdifrx);
832 		break;
833 	case SNDRV_PCM_TRIGGER_SUSPEND:
834 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
835 	case SNDRV_PCM_TRIGGER_STOP:
836 		stm32_spdifrx_stop(spdifrx);
837 		break;
838 	default:
839 		return -EINVAL;
840 	}
841 
842 	return ret;
843 }
844 
845 static void stm32_spdifrx_shutdown(struct snd_pcm_substream *substream,
846 				   struct snd_soc_dai *cpu_dai)
847 {
848 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
849 	unsigned long flags;
850 
851 	spin_lock_irqsave(&spdifrx->irq_lock, flags);
852 	spdifrx->substream = NULL;
853 	spin_unlock_irqrestore(&spdifrx->irq_lock, flags);
854 
855 	clk_disable_unprepare(spdifrx->kclk);
856 }
857 
858 static const struct snd_soc_dai_ops stm32_spdifrx_pcm_dai_ops = {
859 	.probe		= stm32_spdifrx_dai_probe,
860 	.startup	= stm32_spdifrx_startup,
861 	.hw_params	= stm32_spdifrx_hw_params,
862 	.trigger	= stm32_spdifrx_trigger,
863 	.shutdown	= stm32_spdifrx_shutdown,
864 };
865 
866 static struct snd_soc_dai_driver stm32_spdifrx_dai[] = {
867 	{
868 		.capture = {
869 			.stream_name = "CPU-Capture",
870 			.channels_min = 1,
871 			.channels_max = 2,
872 			.rates = SNDRV_PCM_RATE_8000_192000,
873 			.formats = SNDRV_PCM_FMTBIT_S32_LE |
874 				   SNDRV_PCM_FMTBIT_S16_LE,
875 		},
876 		.ops = &stm32_spdifrx_pcm_dai_ops,
877 	}
878 };
879 
880 static const struct snd_pcm_hardware stm32_spdifrx_pcm_hw = {
881 	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_MMAP,
882 	.buffer_bytes_max = 8 * PAGE_SIZE,
883 	.period_bytes_min = 1024,
884 	.period_bytes_max = 4 * PAGE_SIZE,
885 	.periods_min = 2,
886 	.periods_max = 8,
887 };
888 
889 static const struct snd_soc_component_driver stm32_spdifrx_component = {
890 	.name = "stm32-spdifrx",
891 	.legacy_dai_naming = 1,
892 };
893 
894 static const struct snd_dmaengine_pcm_config stm32_spdifrx_pcm_config = {
895 	.pcm_hardware = &stm32_spdifrx_pcm_hw,
896 	.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
897 };
898 
899 static const struct of_device_id stm32_spdifrx_ids[] = {
900 	{
901 		.compatible = "st,stm32h7-spdifrx",
902 		.data = &stm32_h7_spdifrx_regmap_conf
903 	},
904 	{}
905 };
906 
907 static int stm32_spdifrx_parse_of(struct platform_device *pdev,
908 				  struct stm32_spdifrx_data *spdifrx)
909 {
910 	struct device_node *np = pdev->dev.of_node;
911 	const struct of_device_id *of_id;
912 	struct resource *res;
913 
914 	if (!np)
915 		return -ENODEV;
916 
917 	of_id = of_match_device(stm32_spdifrx_ids, &pdev->dev);
918 	if (of_id)
919 		spdifrx->regmap_conf =
920 			(const struct regmap_config *)of_id->data;
921 	else
922 		return -EINVAL;
923 
924 	spdifrx->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
925 	if (IS_ERR(spdifrx->base))
926 		return PTR_ERR(spdifrx->base);
927 
928 	spdifrx->phys_addr = res->start;
929 
930 	spdifrx->kclk = devm_clk_get(&pdev->dev, "kclk");
931 	if (IS_ERR(spdifrx->kclk))
932 		return dev_err_probe(&pdev->dev, PTR_ERR(spdifrx->kclk),
933 				     "Could not get kclk\n");
934 
935 	spdifrx->irq = platform_get_irq(pdev, 0);
936 	if (spdifrx->irq < 0)
937 		return spdifrx->irq;
938 
939 	return 0;
940 }
941 
942 static void stm32_spdifrx_remove(struct platform_device *pdev)
943 {
944 	struct stm32_spdifrx_data *spdifrx = platform_get_drvdata(pdev);
945 
946 	if (spdifrx->ctrl_chan)
947 		dma_release_channel(spdifrx->ctrl_chan);
948 
949 	if (spdifrx->dmab)
950 		snd_dma_free_pages(spdifrx->dmab);
951 
952 	snd_dmaengine_pcm_unregister(&pdev->dev);
953 	snd_soc_unregister_component(&pdev->dev);
954 	pm_runtime_disable(&pdev->dev);
955 }
956 
957 static int stm32_spdifrx_probe(struct platform_device *pdev)
958 {
959 	struct stm32_spdifrx_data *spdifrx;
960 	struct reset_control *rst;
961 	const struct snd_dmaengine_pcm_config *pcm_config = NULL;
962 	u32 ver, idr;
963 	int ret;
964 
965 	spdifrx = devm_kzalloc(&pdev->dev, sizeof(*spdifrx), GFP_KERNEL);
966 	if (!spdifrx)
967 		return -ENOMEM;
968 
969 	spdifrx->pdev = pdev;
970 	init_completion(&spdifrx->cs_completion);
971 	spin_lock_init(&spdifrx->lock);
972 	spin_lock_init(&spdifrx->irq_lock);
973 
974 	platform_set_drvdata(pdev, spdifrx);
975 
976 	ret = stm32_spdifrx_parse_of(pdev, spdifrx);
977 	if (ret)
978 		return ret;
979 
980 	spdifrx->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "kclk",
981 						    spdifrx->base,
982 						    spdifrx->regmap_conf);
983 	if (IS_ERR(spdifrx->regmap))
984 		return dev_err_probe(&pdev->dev, PTR_ERR(spdifrx->regmap),
985 				     "Regmap init error\n");
986 
987 	ret = devm_request_irq(&pdev->dev, spdifrx->irq, stm32_spdifrx_isr, 0,
988 			       dev_name(&pdev->dev), spdifrx);
989 	if (ret) {
990 		dev_err(&pdev->dev, "IRQ request returned %d\n", ret);
991 		return ret;
992 	}
993 
994 	rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
995 	if (IS_ERR(rst))
996 		return dev_err_probe(&pdev->dev, PTR_ERR(rst),
997 				     "Reset controller error\n");
998 
999 	reset_control_assert(rst);
1000 	udelay(2);
1001 	reset_control_deassert(rst);
1002 
1003 	pcm_config = &stm32_spdifrx_pcm_config;
1004 	ret = snd_dmaengine_pcm_register(&pdev->dev, pcm_config, 0);
1005 	if (ret)
1006 		return dev_err_probe(&pdev->dev, ret, "PCM DMA register error\n");
1007 
1008 	ret = snd_soc_register_component(&pdev->dev,
1009 					 &stm32_spdifrx_component,
1010 					 stm32_spdifrx_dai,
1011 					 ARRAY_SIZE(stm32_spdifrx_dai));
1012 	if (ret) {
1013 		snd_dmaengine_pcm_unregister(&pdev->dev);
1014 		return ret;
1015 	}
1016 
1017 	ret = stm32_spdifrx_dma_ctrl_register(&pdev->dev, spdifrx);
1018 	if (ret)
1019 		goto error;
1020 
1021 	ret = regmap_read(spdifrx->regmap, STM32_SPDIFRX_IDR, &idr);
1022 	if (ret)
1023 		goto error;
1024 
1025 	if (idr == SPDIFRX_IPIDR_NUMBER) {
1026 		ret = regmap_read(spdifrx->regmap, STM32_SPDIFRX_VERR, &ver);
1027 		if (ret)
1028 			goto error;
1029 
1030 		dev_dbg(&pdev->dev, "SPDIFRX version: %lu.%lu registered\n",
1031 			FIELD_GET(SPDIFRX_VERR_MAJ_MASK, ver),
1032 			FIELD_GET(SPDIFRX_VERR_MIN_MASK, ver));
1033 	}
1034 
1035 	pm_runtime_enable(&pdev->dev);
1036 
1037 	return ret;
1038 
1039 error:
1040 	stm32_spdifrx_remove(pdev);
1041 
1042 	return ret;
1043 }
1044 
1045 MODULE_DEVICE_TABLE(of, stm32_spdifrx_ids);
1046 
1047 #ifdef CONFIG_PM_SLEEP
1048 static int stm32_spdifrx_suspend(struct device *dev)
1049 {
1050 	struct stm32_spdifrx_data *spdifrx = dev_get_drvdata(dev);
1051 
1052 	regcache_cache_only(spdifrx->regmap, true);
1053 	regcache_mark_dirty(spdifrx->regmap);
1054 
1055 	return 0;
1056 }
1057 
1058 static int stm32_spdifrx_resume(struct device *dev)
1059 {
1060 	struct stm32_spdifrx_data *spdifrx = dev_get_drvdata(dev);
1061 
1062 	regcache_cache_only(spdifrx->regmap, false);
1063 
1064 	return regcache_sync(spdifrx->regmap);
1065 }
1066 #endif /* CONFIG_PM_SLEEP */
1067 
1068 static const struct dev_pm_ops stm32_spdifrx_pm_ops = {
1069 	SET_SYSTEM_SLEEP_PM_OPS(stm32_spdifrx_suspend, stm32_spdifrx_resume)
1070 };
1071 
1072 static struct platform_driver stm32_spdifrx_driver = {
1073 	.driver = {
1074 		.name = "st,stm32-spdifrx",
1075 		.of_match_table = stm32_spdifrx_ids,
1076 		.pm = &stm32_spdifrx_pm_ops,
1077 	},
1078 	.probe = stm32_spdifrx_probe,
1079 	.remove_new = stm32_spdifrx_remove,
1080 };
1081 
1082 module_platform_driver(stm32_spdifrx_driver);
1083 
1084 MODULE_DESCRIPTION("STM32 Soc spdifrx Interface");
1085 MODULE_AUTHOR("Olivier Moysan, <olivier.moysan@st.com>");
1086 MODULE_ALIAS("platform:stm32-spdifrx");
1087 MODULE_LICENSE("GPL v2");
1088