xref: /openbmc/linux/sound/soc/stm/stm32_i2s.c (revision a44e4f3a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  STM32 ALSA SoC Digital Audio Interface (I2S) 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/delay.h>
12 #include <linux/module.h>
13 #include <linux/of_irq.h>
14 #include <linux/of_platform.h>
15 #include <linux/regmap.h>
16 #include <linux/reset.h>
17 #include <linux/spinlock.h>
18 
19 #include <sound/dmaengine_pcm.h>
20 #include <sound/pcm_params.h>
21 
22 #define STM32_I2S_CR1_REG	0x0
23 #define STM32_I2S_CFG1_REG	0x08
24 #define STM32_I2S_CFG2_REG	0x0C
25 #define STM32_I2S_IER_REG	0x10
26 #define STM32_I2S_SR_REG	0x14
27 #define STM32_I2S_IFCR_REG	0x18
28 #define STM32_I2S_TXDR_REG	0X20
29 #define STM32_I2S_RXDR_REG	0x30
30 #define STM32_I2S_CGFR_REG	0X50
31 #define STM32_I2S_HWCFGR_REG	0x3F0
32 #define STM32_I2S_VERR_REG	0x3F4
33 #define STM32_I2S_IPIDR_REG	0x3F8
34 #define STM32_I2S_SIDR_REG	0x3FC
35 
36 /* Bit definition for SPI2S_CR1 register */
37 #define I2S_CR1_SPE		BIT(0)
38 #define I2S_CR1_CSTART		BIT(9)
39 #define I2S_CR1_CSUSP		BIT(10)
40 #define I2S_CR1_HDDIR		BIT(11)
41 #define I2S_CR1_SSI		BIT(12)
42 #define I2S_CR1_CRC33_17	BIT(13)
43 #define I2S_CR1_RCRCI		BIT(14)
44 #define I2S_CR1_TCRCI		BIT(15)
45 
46 /* Bit definition for SPI_CFG2 register */
47 #define I2S_CFG2_IOSWP_SHIFT	15
48 #define I2S_CFG2_IOSWP		BIT(I2S_CFG2_IOSWP_SHIFT)
49 #define I2S_CFG2_LSBFRST	BIT(23)
50 #define I2S_CFG2_AFCNTR		BIT(31)
51 
52 /* Bit definition for SPI_CFG1 register */
53 #define I2S_CFG1_FTHVL_SHIFT	5
54 #define I2S_CFG1_FTHVL_MASK	GENMASK(8, I2S_CFG1_FTHVL_SHIFT)
55 #define I2S_CFG1_FTHVL_SET(x)	((x) << I2S_CFG1_FTHVL_SHIFT)
56 
57 #define I2S_CFG1_TXDMAEN	BIT(15)
58 #define I2S_CFG1_RXDMAEN	BIT(14)
59 
60 /* Bit definition for SPI2S_IER register */
61 #define I2S_IER_RXPIE		BIT(0)
62 #define I2S_IER_TXPIE		BIT(1)
63 #define I2S_IER_DPXPIE		BIT(2)
64 #define I2S_IER_EOTIE		BIT(3)
65 #define I2S_IER_TXTFIE		BIT(4)
66 #define I2S_IER_UDRIE		BIT(5)
67 #define I2S_IER_OVRIE		BIT(6)
68 #define I2S_IER_CRCEIE		BIT(7)
69 #define I2S_IER_TIFREIE		BIT(8)
70 #define I2S_IER_MODFIE		BIT(9)
71 #define I2S_IER_TSERFIE		BIT(10)
72 
73 /* Bit definition for SPI2S_SR register */
74 #define I2S_SR_RXP		BIT(0)
75 #define I2S_SR_TXP		BIT(1)
76 #define I2S_SR_DPXP		BIT(2)
77 #define I2S_SR_EOT		BIT(3)
78 #define I2S_SR_TXTF		BIT(4)
79 #define I2S_SR_UDR		BIT(5)
80 #define I2S_SR_OVR		BIT(6)
81 #define I2S_SR_CRCERR		BIT(7)
82 #define I2S_SR_TIFRE		BIT(8)
83 #define I2S_SR_MODF		BIT(9)
84 #define I2S_SR_TSERF		BIT(10)
85 #define I2S_SR_SUSP		BIT(11)
86 #define I2S_SR_TXC		BIT(12)
87 #define I2S_SR_RXPLVL		GENMASK(14, 13)
88 #define I2S_SR_RXWNE		BIT(15)
89 
90 #define I2S_SR_MASK		GENMASK(15, 0)
91 
92 /* Bit definition for SPI_IFCR register */
93 #define I2S_IFCR_EOTC		BIT(3)
94 #define I2S_IFCR_TXTFC		BIT(4)
95 #define I2S_IFCR_UDRC		BIT(5)
96 #define I2S_IFCR_OVRC		BIT(6)
97 #define I2S_IFCR_CRCEC		BIT(7)
98 #define I2S_IFCR_TIFREC		BIT(8)
99 #define I2S_IFCR_MODFC		BIT(9)
100 #define I2S_IFCR_TSERFC		BIT(10)
101 #define I2S_IFCR_SUSPC		BIT(11)
102 
103 #define I2S_IFCR_MASK		GENMASK(11, 3)
104 
105 /* Bit definition for SPI_I2SCGFR register */
106 #define I2S_CGFR_I2SMOD		BIT(0)
107 
108 #define I2S_CGFR_I2SCFG_SHIFT	1
109 #define I2S_CGFR_I2SCFG_MASK	GENMASK(3, I2S_CGFR_I2SCFG_SHIFT)
110 #define I2S_CGFR_I2SCFG_SET(x)	((x) << I2S_CGFR_I2SCFG_SHIFT)
111 
112 #define I2S_CGFR_I2SSTD_SHIFT	4
113 #define I2S_CGFR_I2SSTD_MASK	GENMASK(5, I2S_CGFR_I2SSTD_SHIFT)
114 #define I2S_CGFR_I2SSTD_SET(x)	((x) << I2S_CGFR_I2SSTD_SHIFT)
115 
116 #define I2S_CGFR_PCMSYNC	BIT(7)
117 
118 #define I2S_CGFR_DATLEN_SHIFT	8
119 #define I2S_CGFR_DATLEN_MASK	GENMASK(9, I2S_CGFR_DATLEN_SHIFT)
120 #define I2S_CGFR_DATLEN_SET(x)	((x) << I2S_CGFR_DATLEN_SHIFT)
121 
122 #define I2S_CGFR_CHLEN_SHIFT	10
123 #define I2S_CGFR_CHLEN		BIT(I2S_CGFR_CHLEN_SHIFT)
124 #define I2S_CGFR_CKPOL		BIT(11)
125 #define I2S_CGFR_FIXCH		BIT(12)
126 #define I2S_CGFR_WSINV		BIT(13)
127 #define I2S_CGFR_DATFMT		BIT(14)
128 
129 #define I2S_CGFR_I2SDIV_SHIFT	16
130 #define I2S_CGFR_I2SDIV_BIT_H	23
131 #define I2S_CGFR_I2SDIV_MASK	GENMASK(I2S_CGFR_I2SDIV_BIT_H,\
132 				I2S_CGFR_I2SDIV_SHIFT)
133 #define I2S_CGFR_I2SDIV_SET(x)	((x) << I2S_CGFR_I2SDIV_SHIFT)
134 #define	I2S_CGFR_I2SDIV_MAX	((1 << (I2S_CGFR_I2SDIV_BIT_H -\
135 				I2S_CGFR_I2SDIV_SHIFT)) - 1)
136 
137 #define I2S_CGFR_ODD_SHIFT	24
138 #define I2S_CGFR_ODD		BIT(I2S_CGFR_ODD_SHIFT)
139 #define I2S_CGFR_MCKOE		BIT(25)
140 
141 /* Registers below apply to I2S version 1.1 and more */
142 
143 /* Bit definition for SPI_HWCFGR register */
144 #define I2S_HWCFGR_I2S_SUPPORT_MASK	GENMASK(15, 12)
145 
146 /* Bit definition for SPI_VERR register */
147 #define I2S_VERR_MIN_MASK	GENMASK(3, 0)
148 #define I2S_VERR_MAJ_MASK	GENMASK(7, 4)
149 
150 /* Bit definition for SPI_IPIDR register */
151 #define I2S_IPIDR_ID_MASK	GENMASK(31, 0)
152 
153 /* Bit definition for SPI_SIDR register */
154 #define I2S_SIDR_ID_MASK	GENMASK(31, 0)
155 
156 #define I2S_IPIDR_NUMBER	0x00130022
157 
158 enum i2s_master_mode {
159 	I2S_MS_NOT_SET,
160 	I2S_MS_MASTER,
161 	I2S_MS_SLAVE,
162 };
163 
164 enum i2s_mode {
165 	I2S_I2SMOD_TX_SLAVE,
166 	I2S_I2SMOD_RX_SLAVE,
167 	I2S_I2SMOD_TX_MASTER,
168 	I2S_I2SMOD_RX_MASTER,
169 	I2S_I2SMOD_FD_SLAVE,
170 	I2S_I2SMOD_FD_MASTER,
171 };
172 
173 enum i2s_fifo_th {
174 	I2S_FIFO_TH_NONE,
175 	I2S_FIFO_TH_ONE_QUARTER,
176 	I2S_FIFO_TH_HALF,
177 	I2S_FIFO_TH_THREE_QUARTER,
178 	I2S_FIFO_TH_FULL,
179 };
180 
181 enum i2s_std {
182 	I2S_STD_I2S,
183 	I2S_STD_LEFT_J,
184 	I2S_STD_RIGHT_J,
185 	I2S_STD_DSP,
186 };
187 
188 enum i2s_datlen {
189 	I2S_I2SMOD_DATLEN_16,
190 	I2S_I2SMOD_DATLEN_24,
191 	I2S_I2SMOD_DATLEN_32,
192 };
193 
194 #define STM32_I2S_FIFO_SIZE		16
195 
196 #define STM32_I2S_IS_MASTER(x)		((x)->ms_flg == I2S_MS_MASTER)
197 #define STM32_I2S_IS_SLAVE(x)		((x)->ms_flg == I2S_MS_SLAVE)
198 
199 /**
200  * struct stm32_i2s_data - private data of I2S
201  * @regmap_conf: I2S register map configuration pointer
202  * @regmap: I2S register map pointer
203  * @pdev: device data pointer
204  * @dai_drv: DAI driver pointer
205  * @dma_data_tx: dma configuration data for tx channel
206  * @dma_data_rx: dma configuration data for tx channel
207  * @substream: PCM substream data pointer
208  * @i2sclk: kernel clock feeding the I2S clock generator
209  * @pclk: peripheral clock driving bus interface
210  * @x8kclk: I2S parent clock for sampling frequencies multiple of 8kHz
211  * @x11kclk: I2S parent clock for sampling frequencies multiple of 11kHz
212  * @base:  mmio register base virtual address
213  * @phys_addr: I2S registers physical base address
214  * @lock_fd: lock to manage race conditions in full duplex mode
215  * @irq_lock: prevent race condition with IRQ
216  * @mclk_rate: master clock frequency (Hz)
217  * @fmt: DAI protocol
218  * @refcount: keep count of opened streams on I2S
219  * @ms_flg: master mode flag.
220  */
221 struct stm32_i2s_data {
222 	const struct regmap_config *regmap_conf;
223 	struct regmap *regmap;
224 	struct platform_device *pdev;
225 	struct snd_soc_dai_driver *dai_drv;
226 	struct snd_dmaengine_dai_dma_data dma_data_tx;
227 	struct snd_dmaengine_dai_dma_data dma_data_rx;
228 	struct snd_pcm_substream *substream;
229 	struct clk *i2sclk;
230 	struct clk *pclk;
231 	struct clk *x8kclk;
232 	struct clk *x11kclk;
233 	void __iomem *base;
234 	dma_addr_t phys_addr;
235 	spinlock_t lock_fd; /* Manage race conditions for full duplex */
236 	spinlock_t irq_lock; /* used to prevent race condition with IRQ */
237 	unsigned int mclk_rate;
238 	unsigned int fmt;
239 	int refcount;
240 	int ms_flg;
241 };
242 
243 static irqreturn_t stm32_i2s_isr(int irq, void *devid)
244 {
245 	struct stm32_i2s_data *i2s = (struct stm32_i2s_data *)devid;
246 	struct platform_device *pdev = i2s->pdev;
247 	u32 sr, ier;
248 	unsigned long flags;
249 	int err = 0;
250 
251 	regmap_read(i2s->regmap, STM32_I2S_SR_REG, &sr);
252 	regmap_read(i2s->regmap, STM32_I2S_IER_REG, &ier);
253 
254 	flags = sr & ier;
255 	if (!flags) {
256 		dev_dbg(&pdev->dev, "Spurious IRQ sr=0x%08x, ier=0x%08x\n",
257 			sr, ier);
258 		return IRQ_NONE;
259 	}
260 
261 	regmap_write_bits(i2s->regmap, STM32_I2S_IFCR_REG,
262 			  I2S_IFCR_MASK, flags);
263 
264 	if (flags & I2S_SR_OVR) {
265 		dev_dbg(&pdev->dev, "Overrun\n");
266 		err = 1;
267 	}
268 
269 	if (flags & I2S_SR_UDR) {
270 		dev_dbg(&pdev->dev, "Underrun\n");
271 		err = 1;
272 	}
273 
274 	if (flags & I2S_SR_TIFRE)
275 		dev_dbg(&pdev->dev, "Frame error\n");
276 
277 	spin_lock(&i2s->irq_lock);
278 	if (err && i2s->substream)
279 		snd_pcm_stop_xrun(i2s->substream);
280 	spin_unlock(&i2s->irq_lock);
281 
282 	return IRQ_HANDLED;
283 }
284 
285 static bool stm32_i2s_readable_reg(struct device *dev, unsigned int reg)
286 {
287 	switch (reg) {
288 	case STM32_I2S_CR1_REG:
289 	case STM32_I2S_CFG1_REG:
290 	case STM32_I2S_CFG2_REG:
291 	case STM32_I2S_IER_REG:
292 	case STM32_I2S_SR_REG:
293 	case STM32_I2S_RXDR_REG:
294 	case STM32_I2S_CGFR_REG:
295 	case STM32_I2S_HWCFGR_REG:
296 	case STM32_I2S_VERR_REG:
297 	case STM32_I2S_IPIDR_REG:
298 	case STM32_I2S_SIDR_REG:
299 		return true;
300 	default:
301 		return false;
302 	}
303 }
304 
305 static bool stm32_i2s_volatile_reg(struct device *dev, unsigned int reg)
306 {
307 	switch (reg) {
308 	case STM32_I2S_SR_REG:
309 	case STM32_I2S_RXDR_REG:
310 		return true;
311 	default:
312 		return false;
313 	}
314 }
315 
316 static bool stm32_i2s_writeable_reg(struct device *dev, unsigned int reg)
317 {
318 	switch (reg) {
319 	case STM32_I2S_CR1_REG:
320 	case STM32_I2S_CFG1_REG:
321 	case STM32_I2S_CFG2_REG:
322 	case STM32_I2S_IER_REG:
323 	case STM32_I2S_IFCR_REG:
324 	case STM32_I2S_TXDR_REG:
325 	case STM32_I2S_CGFR_REG:
326 		return true;
327 	default:
328 		return false;
329 	}
330 }
331 
332 static int stm32_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
333 {
334 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
335 	u32 cgfr;
336 	u32 cgfr_mask =  I2S_CGFR_I2SSTD_MASK | I2S_CGFR_CKPOL |
337 			 I2S_CGFR_WSINV | I2S_CGFR_I2SCFG_MASK;
338 
339 	dev_dbg(cpu_dai->dev, "fmt %x\n", fmt);
340 
341 	/*
342 	 * winv = 0 : default behavior (high/low) for all standards
343 	 * ckpol = 0 for all standards.
344 	 */
345 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
346 	case SND_SOC_DAIFMT_I2S:
347 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_I2S);
348 		break;
349 	case SND_SOC_DAIFMT_MSB:
350 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_LEFT_J);
351 		break;
352 	case SND_SOC_DAIFMT_LSB:
353 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_RIGHT_J);
354 		break;
355 	case SND_SOC_DAIFMT_DSP_A:
356 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_DSP);
357 		break;
358 	/* DSP_B not mapped on I2S PCM long format. 1 bit offset does not fit */
359 	default:
360 		dev_err(cpu_dai->dev, "Unsupported protocol %#x\n",
361 			fmt & SND_SOC_DAIFMT_FORMAT_MASK);
362 		return -EINVAL;
363 	}
364 
365 	/* DAI clock strobing */
366 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
367 	case SND_SOC_DAIFMT_NB_NF:
368 		break;
369 	case SND_SOC_DAIFMT_IB_NF:
370 		cgfr |= I2S_CGFR_CKPOL;
371 		break;
372 	case SND_SOC_DAIFMT_NB_IF:
373 		cgfr |= I2S_CGFR_WSINV;
374 		break;
375 	case SND_SOC_DAIFMT_IB_IF:
376 		cgfr |= I2S_CGFR_CKPOL;
377 		cgfr |= I2S_CGFR_WSINV;
378 		break;
379 	default:
380 		dev_err(cpu_dai->dev, "Unsupported strobing %#x\n",
381 			fmt & SND_SOC_DAIFMT_INV_MASK);
382 		return -EINVAL;
383 	}
384 
385 	/* DAI clock master masks */
386 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
387 	case SND_SOC_DAIFMT_CBM_CFM:
388 		i2s->ms_flg = I2S_MS_SLAVE;
389 		break;
390 	case SND_SOC_DAIFMT_CBS_CFS:
391 		i2s->ms_flg = I2S_MS_MASTER;
392 		break;
393 	default:
394 		dev_err(cpu_dai->dev, "Unsupported mode %#x\n",
395 			fmt & SND_SOC_DAIFMT_MASTER_MASK);
396 		return -EINVAL;
397 	}
398 
399 	i2s->fmt = fmt;
400 	return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
401 				  cgfr_mask, cgfr);
402 }
403 
404 static int stm32_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
405 				int clk_id, unsigned int freq, int dir)
406 {
407 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
408 
409 	dev_dbg(cpu_dai->dev, "I2S MCLK frequency is %uHz\n", freq);
410 
411 	if ((dir == SND_SOC_CLOCK_OUT) && STM32_I2S_IS_MASTER(i2s)) {
412 		i2s->mclk_rate = freq;
413 
414 		/* Enable master clock if master mode and mclk-fs are set */
415 		return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
416 					  I2S_CGFR_MCKOE, I2S_CGFR_MCKOE);
417 	}
418 
419 	return 0;
420 }
421 
422 static int stm32_i2s_configure_clock(struct snd_soc_dai *cpu_dai,
423 				     struct snd_pcm_hw_params *params)
424 {
425 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
426 	unsigned long i2s_clock_rate;
427 	unsigned int tmp, div, real_div, nb_bits, frame_len;
428 	unsigned int rate = params_rate(params);
429 	int ret;
430 	u32 cgfr, cgfr_mask;
431 	bool odd;
432 
433 	if (!(rate % 11025))
434 		clk_set_parent(i2s->i2sclk, i2s->x11kclk);
435 	else
436 		clk_set_parent(i2s->i2sclk, i2s->x8kclk);
437 	i2s_clock_rate = clk_get_rate(i2s->i2sclk);
438 
439 	/*
440 	 * mckl = mclk_ratio x ws
441 	 *   i2s mode : mclk_ratio = 256
442 	 *   dsp mode : mclk_ratio = 128
443 	 *
444 	 * mclk on
445 	 *   i2s mode : div = i2s_clk / (mclk_ratio * ws)
446 	 *   dsp mode : div = i2s_clk / (mclk_ratio * ws)
447 	 * mclk off
448 	 *   i2s mode : div = i2s_clk / (nb_bits x ws)
449 	 *   dsp mode : div = i2s_clk / (nb_bits x ws)
450 	 */
451 	if (i2s->mclk_rate) {
452 		tmp = DIV_ROUND_CLOSEST(i2s_clock_rate, i2s->mclk_rate);
453 	} else {
454 		frame_len = 32;
455 		if ((i2s->fmt & SND_SOC_DAIFMT_FORMAT_MASK) ==
456 		    SND_SOC_DAIFMT_DSP_A)
457 			frame_len = 16;
458 
459 		/* master clock not enabled */
460 		ret = regmap_read(i2s->regmap, STM32_I2S_CGFR_REG, &cgfr);
461 		if (ret < 0)
462 			return ret;
463 
464 		nb_bits = frame_len * ((cgfr & I2S_CGFR_CHLEN) + 1);
465 		tmp = DIV_ROUND_CLOSEST(i2s_clock_rate, (nb_bits * rate));
466 	}
467 
468 	/* Check the parity of the divider */
469 	odd = tmp & 0x1;
470 
471 	/* Compute the div prescaler */
472 	div = tmp >> 1;
473 
474 	cgfr = I2S_CGFR_I2SDIV_SET(div) | (odd << I2S_CGFR_ODD_SHIFT);
475 	cgfr_mask = I2S_CGFR_I2SDIV_MASK | I2S_CGFR_ODD;
476 
477 	real_div = ((2 * div) + odd);
478 	dev_dbg(cpu_dai->dev, "I2S clk: %ld, SCLK: %d\n",
479 		i2s_clock_rate, rate);
480 	dev_dbg(cpu_dai->dev, "Divider: 2*%d(div)+%d(odd) = %d\n",
481 		div, odd, real_div);
482 
483 	if (((div == 1) && odd) || (div > I2S_CGFR_I2SDIV_MAX)) {
484 		dev_err(cpu_dai->dev, "Wrong divider setting\n");
485 		return -EINVAL;
486 	}
487 
488 	if (!div && !odd)
489 		dev_warn(cpu_dai->dev, "real divider forced to 1\n");
490 
491 	ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
492 				 cgfr_mask, cgfr);
493 	if (ret < 0)
494 		return ret;
495 
496 	/* Set bitclock and frameclock to their inactive state */
497 	return regmap_update_bits(i2s->regmap, STM32_I2S_CFG2_REG,
498 				  I2S_CFG2_AFCNTR, I2S_CFG2_AFCNTR);
499 }
500 
501 static int stm32_i2s_configure(struct snd_soc_dai *cpu_dai,
502 			       struct snd_pcm_hw_params *params,
503 			       struct snd_pcm_substream *substream)
504 {
505 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
506 	int format = params_width(params);
507 	u32 cfgr, cfgr_mask, cfg1;
508 	unsigned int fthlv;
509 	int ret;
510 
511 	switch (format) {
512 	case 16:
513 		cfgr = I2S_CGFR_DATLEN_SET(I2S_I2SMOD_DATLEN_16);
514 		cfgr_mask = I2S_CGFR_DATLEN_MASK | I2S_CGFR_CHLEN;
515 		break;
516 	case 32:
517 		cfgr = I2S_CGFR_DATLEN_SET(I2S_I2SMOD_DATLEN_32) |
518 					   I2S_CGFR_CHLEN;
519 		cfgr_mask = I2S_CGFR_DATLEN_MASK | I2S_CGFR_CHLEN;
520 		break;
521 	default:
522 		dev_err(cpu_dai->dev, "Unexpected format %d", format);
523 		return -EINVAL;
524 	}
525 
526 	if (STM32_I2S_IS_SLAVE(i2s)) {
527 		cfgr |= I2S_CGFR_I2SCFG_SET(I2S_I2SMOD_FD_SLAVE);
528 
529 		/* As data length is either 16 or 32 bits, fixch always set */
530 		cfgr |= I2S_CGFR_FIXCH;
531 		cfgr_mask |= I2S_CGFR_FIXCH;
532 	} else {
533 		cfgr |= I2S_CGFR_I2SCFG_SET(I2S_I2SMOD_FD_MASTER);
534 	}
535 	cfgr_mask |= I2S_CGFR_I2SCFG_MASK;
536 
537 	ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
538 				 cfgr_mask, cfgr);
539 	if (ret < 0)
540 		return ret;
541 
542 	fthlv = STM32_I2S_FIFO_SIZE * I2S_FIFO_TH_ONE_QUARTER / 4;
543 	cfg1 = I2S_CFG1_FTHVL_SET(fthlv - 1);
544 
545 	return regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
546 				  I2S_CFG1_FTHVL_MASK, cfg1);
547 }
548 
549 static int stm32_i2s_startup(struct snd_pcm_substream *substream,
550 			     struct snd_soc_dai *cpu_dai)
551 {
552 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
553 	unsigned long flags;
554 	int ret;
555 
556 	spin_lock_irqsave(&i2s->irq_lock, flags);
557 	i2s->substream = substream;
558 	spin_unlock_irqrestore(&i2s->irq_lock, flags);
559 
560 	if ((i2s->fmt & SND_SOC_DAIFMT_FORMAT_MASK) != SND_SOC_DAIFMT_DSP_A)
561 		snd_pcm_hw_constraint_single(substream->runtime,
562 					     SNDRV_PCM_HW_PARAM_CHANNELS, 2);
563 
564 	ret = clk_prepare_enable(i2s->i2sclk);
565 	if (ret < 0) {
566 		dev_err(cpu_dai->dev, "Failed to enable clock: %d\n", ret);
567 		return ret;
568 	}
569 
570 	return regmap_write_bits(i2s->regmap, STM32_I2S_IFCR_REG,
571 				 I2S_IFCR_MASK, I2S_IFCR_MASK);
572 }
573 
574 static int stm32_i2s_hw_params(struct snd_pcm_substream *substream,
575 			       struct snd_pcm_hw_params *params,
576 			       struct snd_soc_dai *cpu_dai)
577 {
578 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
579 	int ret;
580 
581 	ret = stm32_i2s_configure(cpu_dai, params, substream);
582 	if (ret < 0) {
583 		dev_err(cpu_dai->dev, "Configuration returned error %d\n", ret);
584 		return ret;
585 	}
586 
587 	if (STM32_I2S_IS_MASTER(i2s))
588 		ret = stm32_i2s_configure_clock(cpu_dai, params);
589 
590 	return ret;
591 }
592 
593 static int stm32_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
594 			     struct snd_soc_dai *cpu_dai)
595 {
596 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
597 	bool playback_flg = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK);
598 	u32 cfg1_mask, ier;
599 	int ret;
600 
601 	switch (cmd) {
602 	case SNDRV_PCM_TRIGGER_START:
603 	case SNDRV_PCM_TRIGGER_RESUME:
604 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
605 		/* Enable i2s */
606 		dev_dbg(cpu_dai->dev, "start I2S %s\n",
607 			playback_flg ? "playback" : "capture");
608 
609 		cfg1_mask = I2S_CFG1_RXDMAEN | I2S_CFG1_TXDMAEN;
610 		regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
611 				   cfg1_mask, cfg1_mask);
612 
613 		ret = regmap_update_bits(i2s->regmap, STM32_I2S_CR1_REG,
614 					 I2S_CR1_SPE, I2S_CR1_SPE);
615 		if (ret < 0) {
616 			dev_err(cpu_dai->dev, "Error %d enabling I2S\n", ret);
617 			return ret;
618 		}
619 
620 		ret = regmap_write_bits(i2s->regmap, STM32_I2S_CR1_REG,
621 					I2S_CR1_CSTART, I2S_CR1_CSTART);
622 		if (ret < 0) {
623 			dev_err(cpu_dai->dev, "Error %d starting I2S\n", ret);
624 			return ret;
625 		}
626 
627 		regmap_write_bits(i2s->regmap, STM32_I2S_IFCR_REG,
628 				  I2S_IFCR_MASK, I2S_IFCR_MASK);
629 
630 		spin_lock(&i2s->lock_fd);
631 		i2s->refcount++;
632 		if (playback_flg) {
633 			ier = I2S_IER_UDRIE;
634 		} else {
635 			ier = I2S_IER_OVRIE;
636 
637 			if (STM32_I2S_IS_MASTER(i2s) && i2s->refcount == 1)
638 				/* dummy write to gate bus clocks */
639 				regmap_write(i2s->regmap,
640 					     STM32_I2S_TXDR_REG, 0);
641 		}
642 		spin_unlock(&i2s->lock_fd);
643 
644 		if (STM32_I2S_IS_SLAVE(i2s))
645 			ier |= I2S_IER_TIFREIE;
646 
647 		regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG, ier, ier);
648 		break;
649 	case SNDRV_PCM_TRIGGER_STOP:
650 	case SNDRV_PCM_TRIGGER_SUSPEND:
651 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
652 		dev_dbg(cpu_dai->dev, "stop I2S %s\n",
653 			playback_flg ? "playback" : "capture");
654 
655 		if (playback_flg)
656 			regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG,
657 					   I2S_IER_UDRIE,
658 					   (unsigned int)~I2S_IER_UDRIE);
659 		else
660 			regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG,
661 					   I2S_IER_OVRIE,
662 					   (unsigned int)~I2S_IER_OVRIE);
663 
664 		spin_lock(&i2s->lock_fd);
665 		i2s->refcount--;
666 		if (i2s->refcount) {
667 			spin_unlock(&i2s->lock_fd);
668 			break;
669 		}
670 
671 		ret = regmap_update_bits(i2s->regmap, STM32_I2S_CR1_REG,
672 					 I2S_CR1_SPE, 0);
673 		if (ret < 0) {
674 			dev_err(cpu_dai->dev, "Error %d disabling I2S\n", ret);
675 			spin_unlock(&i2s->lock_fd);
676 			return ret;
677 		}
678 		spin_unlock(&i2s->lock_fd);
679 
680 		cfg1_mask = I2S_CFG1_RXDMAEN | I2S_CFG1_TXDMAEN;
681 		regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
682 				   cfg1_mask, 0);
683 		break;
684 	default:
685 		return -EINVAL;
686 	}
687 
688 	return 0;
689 }
690 
691 static void stm32_i2s_shutdown(struct snd_pcm_substream *substream,
692 			       struct snd_soc_dai *cpu_dai)
693 {
694 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
695 	unsigned long flags;
696 
697 	regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
698 			   I2S_CGFR_MCKOE, (unsigned int)~I2S_CGFR_MCKOE);
699 
700 	clk_disable_unprepare(i2s->i2sclk);
701 
702 	spin_lock_irqsave(&i2s->irq_lock, flags);
703 	i2s->substream = NULL;
704 	spin_unlock_irqrestore(&i2s->irq_lock, flags);
705 }
706 
707 static int stm32_i2s_dai_probe(struct snd_soc_dai *cpu_dai)
708 {
709 	struct stm32_i2s_data *i2s = dev_get_drvdata(cpu_dai->dev);
710 	struct snd_dmaengine_dai_dma_data *dma_data_tx = &i2s->dma_data_tx;
711 	struct snd_dmaengine_dai_dma_data *dma_data_rx = &i2s->dma_data_rx;
712 
713 	/* Buswidth will be set by framework */
714 	dma_data_tx->addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
715 	dma_data_tx->addr = (dma_addr_t)(i2s->phys_addr) + STM32_I2S_TXDR_REG;
716 	dma_data_tx->maxburst = 1;
717 	dma_data_rx->addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
718 	dma_data_rx->addr = (dma_addr_t)(i2s->phys_addr) + STM32_I2S_RXDR_REG;
719 	dma_data_rx->maxburst = 1;
720 
721 	snd_soc_dai_init_dma_data(cpu_dai, dma_data_tx, dma_data_rx);
722 
723 	return 0;
724 }
725 
726 static const struct regmap_config stm32_h7_i2s_regmap_conf = {
727 	.reg_bits = 32,
728 	.reg_stride = 4,
729 	.val_bits = 32,
730 	.max_register = STM32_I2S_SIDR_REG,
731 	.readable_reg = stm32_i2s_readable_reg,
732 	.volatile_reg = stm32_i2s_volatile_reg,
733 	.writeable_reg = stm32_i2s_writeable_reg,
734 	.num_reg_defaults_raw = STM32_I2S_SIDR_REG / sizeof(u32) + 1,
735 	.fast_io = true,
736 	.cache_type = REGCACHE_FLAT,
737 };
738 
739 static const struct snd_soc_dai_ops stm32_i2s_pcm_dai_ops = {
740 	.set_sysclk	= stm32_i2s_set_sysclk,
741 	.set_fmt	= stm32_i2s_set_dai_fmt,
742 	.startup	= stm32_i2s_startup,
743 	.hw_params	= stm32_i2s_hw_params,
744 	.trigger	= stm32_i2s_trigger,
745 	.shutdown	= stm32_i2s_shutdown,
746 };
747 
748 static const struct snd_pcm_hardware stm32_i2s_pcm_hw = {
749 	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_MMAP,
750 	.buffer_bytes_max = 8 * PAGE_SIZE,
751 	.period_bytes_min = 1024,
752 	.period_bytes_max = 4 * PAGE_SIZE,
753 	.periods_min = 2,
754 	.periods_max = 8,
755 };
756 
757 static const struct snd_dmaengine_pcm_config stm32_i2s_pcm_config = {
758 	.pcm_hardware	= &stm32_i2s_pcm_hw,
759 	.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
760 	.prealloc_buffer_size = PAGE_SIZE * 8,
761 };
762 
763 static const struct snd_soc_component_driver stm32_i2s_component = {
764 	.name = "stm32-i2s",
765 };
766 
767 static void stm32_i2s_dai_init(struct snd_soc_pcm_stream *stream,
768 			       char *stream_name)
769 {
770 	stream->stream_name = stream_name;
771 	stream->channels_min = 1;
772 	stream->channels_max = 2;
773 	stream->rates = SNDRV_PCM_RATE_8000_192000;
774 	stream->formats = SNDRV_PCM_FMTBIT_S16_LE |
775 				   SNDRV_PCM_FMTBIT_S32_LE;
776 }
777 
778 static int stm32_i2s_dais_init(struct platform_device *pdev,
779 			       struct stm32_i2s_data *i2s)
780 {
781 	struct snd_soc_dai_driver *dai_ptr;
782 
783 	dai_ptr = devm_kzalloc(&pdev->dev, sizeof(struct snd_soc_dai_driver),
784 			       GFP_KERNEL);
785 	if (!dai_ptr)
786 		return -ENOMEM;
787 
788 	dai_ptr->probe = stm32_i2s_dai_probe;
789 	dai_ptr->ops = &stm32_i2s_pcm_dai_ops;
790 	dai_ptr->id = 1;
791 	stm32_i2s_dai_init(&dai_ptr->playback, "playback");
792 	stm32_i2s_dai_init(&dai_ptr->capture, "capture");
793 	i2s->dai_drv = dai_ptr;
794 
795 	return 0;
796 }
797 
798 static const struct of_device_id stm32_i2s_ids[] = {
799 	{
800 		.compatible = "st,stm32h7-i2s",
801 		.data = &stm32_h7_i2s_regmap_conf
802 	},
803 	{},
804 };
805 
806 static int stm32_i2s_parse_dt(struct platform_device *pdev,
807 			      struct stm32_i2s_data *i2s)
808 {
809 	struct device_node *np = pdev->dev.of_node;
810 	const struct of_device_id *of_id;
811 	struct reset_control *rst;
812 	struct resource *res;
813 	int irq, ret;
814 
815 	if (!np)
816 		return -ENODEV;
817 
818 	of_id = of_match_device(stm32_i2s_ids, &pdev->dev);
819 	if (of_id)
820 		i2s->regmap_conf = (const struct regmap_config *)of_id->data;
821 	else
822 		return -EINVAL;
823 
824 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
825 	i2s->base = devm_ioremap_resource(&pdev->dev, res);
826 	if (IS_ERR(i2s->base))
827 		return PTR_ERR(i2s->base);
828 
829 	i2s->phys_addr = res->start;
830 
831 	/* Get clocks */
832 	i2s->pclk = devm_clk_get(&pdev->dev, "pclk");
833 	if (IS_ERR(i2s->pclk)) {
834 		dev_err(&pdev->dev, "Could not get pclk\n");
835 		return PTR_ERR(i2s->pclk);
836 	}
837 
838 	i2s->i2sclk = devm_clk_get(&pdev->dev, "i2sclk");
839 	if (IS_ERR(i2s->i2sclk)) {
840 		dev_err(&pdev->dev, "Could not get i2sclk\n");
841 		return PTR_ERR(i2s->i2sclk);
842 	}
843 
844 	i2s->x8kclk = devm_clk_get(&pdev->dev, "x8k");
845 	if (IS_ERR(i2s->x8kclk)) {
846 		dev_err(&pdev->dev, "missing x8k parent clock\n");
847 		return PTR_ERR(i2s->x8kclk);
848 	}
849 
850 	i2s->x11kclk = devm_clk_get(&pdev->dev, "x11k");
851 	if (IS_ERR(i2s->x11kclk)) {
852 		dev_err(&pdev->dev, "missing x11k parent clock\n");
853 		return PTR_ERR(i2s->x11kclk);
854 	}
855 
856 	/* Get irqs */
857 	irq = platform_get_irq(pdev, 0);
858 	if (irq < 0)
859 		return irq;
860 
861 	ret = devm_request_irq(&pdev->dev, irq, stm32_i2s_isr, IRQF_ONESHOT,
862 			       dev_name(&pdev->dev), i2s);
863 	if (ret) {
864 		dev_err(&pdev->dev, "irq request returned %d\n", ret);
865 		return ret;
866 	}
867 
868 	/* Reset */
869 	rst = devm_reset_control_get_exclusive(&pdev->dev, NULL);
870 	if (!IS_ERR(rst)) {
871 		reset_control_assert(rst);
872 		udelay(2);
873 		reset_control_deassert(rst);
874 	}
875 
876 	return 0;
877 }
878 
879 static int stm32_i2s_probe(struct platform_device *pdev)
880 {
881 	struct stm32_i2s_data *i2s;
882 	u32 val;
883 	int ret;
884 
885 	i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
886 	if (!i2s)
887 		return -ENOMEM;
888 
889 	ret = stm32_i2s_parse_dt(pdev, i2s);
890 	if (ret)
891 		return ret;
892 
893 	i2s->pdev = pdev;
894 	i2s->ms_flg = I2S_MS_NOT_SET;
895 	spin_lock_init(&i2s->lock_fd);
896 	spin_lock_init(&i2s->irq_lock);
897 	platform_set_drvdata(pdev, i2s);
898 
899 	ret = stm32_i2s_dais_init(pdev, i2s);
900 	if (ret)
901 		return ret;
902 
903 	i2s->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "pclk",
904 						i2s->base, i2s->regmap_conf);
905 	if (IS_ERR(i2s->regmap)) {
906 		dev_err(&pdev->dev, "regmap init failed\n");
907 		return PTR_ERR(i2s->regmap);
908 	}
909 
910 	ret = devm_snd_soc_register_component(&pdev->dev, &stm32_i2s_component,
911 					      i2s->dai_drv, 1);
912 	if (ret)
913 		return ret;
914 
915 	ret = devm_snd_dmaengine_pcm_register(&pdev->dev,
916 					      &stm32_i2s_pcm_config, 0);
917 	if (ret)
918 		return ret;
919 
920 	/* Set SPI/I2S in i2s mode */
921 	ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
922 				 I2S_CGFR_I2SMOD, I2S_CGFR_I2SMOD);
923 	if (ret)
924 		return ret;
925 
926 	ret = regmap_read(i2s->regmap, STM32_I2S_IPIDR_REG, &val);
927 	if (ret)
928 		return ret;
929 
930 	if (val == I2S_IPIDR_NUMBER) {
931 		ret = regmap_read(i2s->regmap, STM32_I2S_HWCFGR_REG, &val);
932 		if (ret)
933 			return ret;
934 
935 		if (!FIELD_GET(I2S_HWCFGR_I2S_SUPPORT_MASK, val)) {
936 			dev_err(&pdev->dev,
937 				"Device does not support i2s mode\n");
938 			return -EPERM;
939 		}
940 
941 		ret = regmap_read(i2s->regmap, STM32_I2S_VERR_REG, &val);
942 
943 		dev_dbg(&pdev->dev, "I2S version: %lu.%lu registered\n",
944 			FIELD_GET(I2S_VERR_MAJ_MASK, val),
945 			FIELD_GET(I2S_VERR_MIN_MASK, val));
946 	}
947 
948 	return ret;
949 }
950 
951 MODULE_DEVICE_TABLE(of, stm32_i2s_ids);
952 
953 #ifdef CONFIG_PM_SLEEP
954 static int stm32_i2s_suspend(struct device *dev)
955 {
956 	struct stm32_i2s_data *i2s = dev_get_drvdata(dev);
957 
958 	regcache_cache_only(i2s->regmap, true);
959 	regcache_mark_dirty(i2s->regmap);
960 
961 	return 0;
962 }
963 
964 static int stm32_i2s_resume(struct device *dev)
965 {
966 	struct stm32_i2s_data *i2s = dev_get_drvdata(dev);
967 
968 	regcache_cache_only(i2s->regmap, false);
969 	return regcache_sync(i2s->regmap);
970 }
971 #endif /* CONFIG_PM_SLEEP */
972 
973 static const struct dev_pm_ops stm32_i2s_pm_ops = {
974 	SET_SYSTEM_SLEEP_PM_OPS(stm32_i2s_suspend, stm32_i2s_resume)
975 };
976 
977 static struct platform_driver stm32_i2s_driver = {
978 	.driver = {
979 		.name = "st,stm32-i2s",
980 		.of_match_table = stm32_i2s_ids,
981 		.pm = &stm32_i2s_pm_ops,
982 	},
983 	.probe = stm32_i2s_probe,
984 };
985 
986 module_platform_driver(stm32_i2s_driver);
987 
988 MODULE_DESCRIPTION("STM32 Soc i2s Interface");
989 MODULE_AUTHOR("Olivier Moysan, <olivier.moysan@st.com>");
990 MODULE_ALIAS("platform:stm32-i2s");
991 MODULE_LICENSE("GPL v2");
992