xref: /openbmc/linux/sound/soc/stm/stm32_i2s.c (revision 3fc41476)
1 /*
2  *  STM32 ALSA SoC Digital Audio Interface (I2S) driver.
3  *
4  * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
5  * Author(s): Olivier Moysan <olivier.moysan@st.com> for STMicroelectronics.
6  *
7  * License terms: GPL V2.0.
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License version 2 as published by
11  * the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
15  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
16  * details.
17  */
18 
19 #include <linux/clk.h>
20 #include <linux/delay.h>
21 #include <linux/module.h>
22 #include <linux/of_irq.h>
23 #include <linux/of_platform.h>
24 #include <linux/regmap.h>
25 #include <linux/reset.h>
26 #include <linux/spinlock.h>
27 
28 #include <sound/dmaengine_pcm.h>
29 #include <sound/pcm_params.h>
30 
31 #define STM32_I2S_CR1_REG	0x0
32 #define STM32_I2S_CFG1_REG	0x08
33 #define STM32_I2S_CFG2_REG	0x0C
34 #define STM32_I2S_IER_REG	0x10
35 #define STM32_I2S_SR_REG	0x14
36 #define STM32_I2S_IFCR_REG	0x18
37 #define STM32_I2S_TXDR_REG	0X20
38 #define STM32_I2S_RXDR_REG	0x30
39 #define STM32_I2S_CGFR_REG	0X50
40 
41 /* Bit definition for SPI2S_CR1 register */
42 #define I2S_CR1_SPE		BIT(0)
43 #define I2S_CR1_CSTART		BIT(9)
44 #define I2S_CR1_CSUSP		BIT(10)
45 #define I2S_CR1_HDDIR		BIT(11)
46 #define I2S_CR1_SSI		BIT(12)
47 #define I2S_CR1_CRC33_17	BIT(13)
48 #define I2S_CR1_RCRCI		BIT(14)
49 #define I2S_CR1_TCRCI		BIT(15)
50 
51 /* Bit definition for SPI_CFG2 register */
52 #define I2S_CFG2_IOSWP_SHIFT	15
53 #define I2S_CFG2_IOSWP		BIT(I2S_CFG2_IOSWP_SHIFT)
54 #define I2S_CFG2_LSBFRST	BIT(23)
55 #define I2S_CFG2_AFCNTR		BIT(31)
56 
57 /* Bit definition for SPI_CFG1 register */
58 #define I2S_CFG1_FTHVL_SHIFT	5
59 #define I2S_CFG1_FTHVL_MASK	GENMASK(8, I2S_CFG1_FTHVL_SHIFT)
60 #define I2S_CFG1_FTHVL_SET(x)	((x) << I2S_CFG1_FTHVL_SHIFT)
61 
62 #define I2S_CFG1_TXDMAEN	BIT(15)
63 #define I2S_CFG1_RXDMAEN	BIT(14)
64 
65 /* Bit definition for SPI2S_IER register */
66 #define I2S_IER_RXPIE		BIT(0)
67 #define I2S_IER_TXPIE		BIT(1)
68 #define I2S_IER_DPXPIE		BIT(2)
69 #define I2S_IER_EOTIE		BIT(3)
70 #define I2S_IER_TXTFIE		BIT(4)
71 #define I2S_IER_UDRIE		BIT(5)
72 #define I2S_IER_OVRIE		BIT(6)
73 #define I2S_IER_CRCEIE		BIT(7)
74 #define I2S_IER_TIFREIE		BIT(8)
75 #define I2S_IER_MODFIE		BIT(9)
76 #define I2S_IER_TSERFIE		BIT(10)
77 
78 /* Bit definition for SPI2S_SR register */
79 #define I2S_SR_RXP		BIT(0)
80 #define I2S_SR_TXP		BIT(1)
81 #define I2S_SR_DPXP		BIT(2)
82 #define I2S_SR_EOT		BIT(3)
83 #define I2S_SR_TXTF		BIT(4)
84 #define I2S_SR_UDR		BIT(5)
85 #define I2S_SR_OVR		BIT(6)
86 #define I2S_SR_CRCERR		BIT(7)
87 #define I2S_SR_TIFRE		BIT(8)
88 #define I2S_SR_MODF		BIT(9)
89 #define I2S_SR_TSERF		BIT(10)
90 #define I2S_SR_SUSP		BIT(11)
91 #define I2S_SR_TXC		BIT(12)
92 #define I2S_SR_RXPLVL		GENMASK(14, 13)
93 #define I2S_SR_RXWNE		BIT(15)
94 
95 #define I2S_SR_MASK		GENMASK(15, 0)
96 
97 /* Bit definition for SPI_IFCR register */
98 #define I2S_IFCR_EOTC		BIT(3)
99 #define I2S_IFCR_TXTFC		BIT(4)
100 #define I2S_IFCR_UDRC		BIT(5)
101 #define I2S_IFCR_OVRC		BIT(6)
102 #define I2S_IFCR_CRCEC		BIT(7)
103 #define I2S_IFCR_TIFREC		BIT(8)
104 #define I2S_IFCR_MODFC		BIT(9)
105 #define I2S_IFCR_TSERFC		BIT(10)
106 #define I2S_IFCR_SUSPC		BIT(11)
107 
108 #define I2S_IFCR_MASK		GENMASK(11, 3)
109 
110 /* Bit definition for SPI_I2SCGFR register */
111 #define I2S_CGFR_I2SMOD		BIT(0)
112 
113 #define I2S_CGFR_I2SCFG_SHIFT	1
114 #define I2S_CGFR_I2SCFG_MASK	GENMASK(3, I2S_CGFR_I2SCFG_SHIFT)
115 #define I2S_CGFR_I2SCFG_SET(x)	((x) << I2S_CGFR_I2SCFG_SHIFT)
116 
117 #define I2S_CGFR_I2SSTD_SHIFT	4
118 #define I2S_CGFR_I2SSTD_MASK	GENMASK(5, I2S_CGFR_I2SSTD_SHIFT)
119 #define I2S_CGFR_I2SSTD_SET(x)	((x) << I2S_CGFR_I2SSTD_SHIFT)
120 
121 #define I2S_CGFR_PCMSYNC	BIT(7)
122 
123 #define I2S_CGFR_DATLEN_SHIFT	8
124 #define I2S_CGFR_DATLEN_MASK	GENMASK(9, I2S_CGFR_DATLEN_SHIFT)
125 #define I2S_CGFR_DATLEN_SET(x)	((x) << I2S_CGFR_DATLEN_SHIFT)
126 
127 #define I2S_CGFR_CHLEN_SHIFT	10
128 #define I2S_CGFR_CHLEN		BIT(I2S_CGFR_CHLEN_SHIFT)
129 #define I2S_CGFR_CKPOL		BIT(11)
130 #define I2S_CGFR_FIXCH		BIT(12)
131 #define I2S_CGFR_WSINV		BIT(13)
132 #define I2S_CGFR_DATFMT		BIT(14)
133 
134 #define I2S_CGFR_I2SDIV_SHIFT	16
135 #define I2S_CGFR_I2SDIV_BIT_H	23
136 #define I2S_CGFR_I2SDIV_MASK	GENMASK(I2S_CGFR_I2SDIV_BIT_H,\
137 				I2S_CGFR_I2SDIV_SHIFT)
138 #define I2S_CGFR_I2SDIV_SET(x)	((x) << I2S_CGFR_I2SDIV_SHIFT)
139 #define	I2S_CGFR_I2SDIV_MAX	((1 << (I2S_CGFR_I2SDIV_BIT_H -\
140 				I2S_CGFR_I2SDIV_SHIFT)) - 1)
141 
142 #define I2S_CGFR_ODD_SHIFT	24
143 #define I2S_CGFR_ODD		BIT(I2S_CGFR_ODD_SHIFT)
144 #define I2S_CGFR_MCKOE		BIT(25)
145 
146 enum i2s_master_mode {
147 	I2S_MS_NOT_SET,
148 	I2S_MS_MASTER,
149 	I2S_MS_SLAVE,
150 };
151 
152 enum i2s_mode {
153 	I2S_I2SMOD_TX_SLAVE,
154 	I2S_I2SMOD_RX_SLAVE,
155 	I2S_I2SMOD_TX_MASTER,
156 	I2S_I2SMOD_RX_MASTER,
157 	I2S_I2SMOD_FD_SLAVE,
158 	I2S_I2SMOD_FD_MASTER,
159 };
160 
161 enum i2s_fifo_th {
162 	I2S_FIFO_TH_NONE,
163 	I2S_FIFO_TH_ONE_QUARTER,
164 	I2S_FIFO_TH_HALF,
165 	I2S_FIFO_TH_THREE_QUARTER,
166 	I2S_FIFO_TH_FULL,
167 };
168 
169 enum i2s_std {
170 	I2S_STD_I2S,
171 	I2S_STD_LEFT_J,
172 	I2S_STD_RIGHT_J,
173 	I2S_STD_DSP,
174 };
175 
176 enum i2s_datlen {
177 	I2S_I2SMOD_DATLEN_16,
178 	I2S_I2SMOD_DATLEN_24,
179 	I2S_I2SMOD_DATLEN_32,
180 };
181 
182 #define STM32_I2S_FIFO_SIZE		16
183 
184 #define STM32_I2S_IS_MASTER(x)		((x)->ms_flg == I2S_MS_MASTER)
185 #define STM32_I2S_IS_SLAVE(x)		((x)->ms_flg == I2S_MS_SLAVE)
186 
187 /**
188  * struct stm32_i2s_data - private data of I2S
189  * @regmap_conf: I2S register map configuration pointer
190  * @regmap: I2S register map pointer
191  * @pdev: device data pointer
192  * @dai_drv: DAI driver pointer
193  * @dma_data_tx: dma configuration data for tx channel
194  * @dma_data_rx: dma configuration data for tx channel
195  * @substream: PCM substream data pointer
196  * @i2sclk: kernel clock feeding the I2S clock generator
197  * @pclk: peripheral clock driving bus interface
198  * @x8kclk: I2S parent clock for sampling frequencies multiple of 8kHz
199  * @x11kclk: I2S parent clock for sampling frequencies multiple of 11kHz
200  * @base:  mmio register base virtual address
201  * @phys_addr: I2S registers physical base address
202  * @lock_fd: lock to manage race conditions in full duplex mode
203  * @irq_lock: prevent race condition with IRQ
204  * @mclk_rate: master clock frequency (Hz)
205  * @fmt: DAI protocol
206  * @refcount: keep count of opened streams on I2S
207  * @ms_flg: master mode flag.
208  */
209 struct stm32_i2s_data {
210 	const struct regmap_config *regmap_conf;
211 	struct regmap *regmap;
212 	struct platform_device *pdev;
213 	struct snd_soc_dai_driver *dai_drv;
214 	struct snd_dmaengine_dai_dma_data dma_data_tx;
215 	struct snd_dmaengine_dai_dma_data dma_data_rx;
216 	struct snd_pcm_substream *substream;
217 	struct clk *i2sclk;
218 	struct clk *pclk;
219 	struct clk *x8kclk;
220 	struct clk *x11kclk;
221 	void __iomem *base;
222 	dma_addr_t phys_addr;
223 	spinlock_t lock_fd; /* Manage race conditions for full duplex */
224 	spinlock_t irq_lock; /* used to prevent race condition with IRQ */
225 	unsigned int mclk_rate;
226 	unsigned int fmt;
227 	int refcount;
228 	int ms_flg;
229 };
230 
231 static irqreturn_t stm32_i2s_isr(int irq, void *devid)
232 {
233 	struct stm32_i2s_data *i2s = (struct stm32_i2s_data *)devid;
234 	struct platform_device *pdev = i2s->pdev;
235 	u32 sr, ier;
236 	unsigned long flags;
237 	int err = 0;
238 
239 	regmap_read(i2s->regmap, STM32_I2S_SR_REG, &sr);
240 	regmap_read(i2s->regmap, STM32_I2S_IER_REG, &ier);
241 
242 	flags = sr & ier;
243 	if (!flags) {
244 		dev_dbg(&pdev->dev, "Spurious IRQ sr=0x%08x, ier=0x%08x\n",
245 			sr, ier);
246 		return IRQ_NONE;
247 	}
248 
249 	regmap_write_bits(i2s->regmap, STM32_I2S_IFCR_REG,
250 			  I2S_IFCR_MASK, flags);
251 
252 	if (flags & I2S_SR_OVR) {
253 		dev_dbg(&pdev->dev, "Overrun\n");
254 		err = 1;
255 	}
256 
257 	if (flags & I2S_SR_UDR) {
258 		dev_dbg(&pdev->dev, "Underrun\n");
259 		err = 1;
260 	}
261 
262 	if (flags & I2S_SR_TIFRE)
263 		dev_dbg(&pdev->dev, "Frame error\n");
264 
265 	spin_lock(&i2s->irq_lock);
266 	if (err && i2s->substream)
267 		snd_pcm_stop_xrun(i2s->substream);
268 	spin_unlock(&i2s->irq_lock);
269 
270 	return IRQ_HANDLED;
271 }
272 
273 static bool stm32_i2s_readable_reg(struct device *dev, unsigned int reg)
274 {
275 	switch (reg) {
276 	case STM32_I2S_CR1_REG:
277 	case STM32_I2S_CFG1_REG:
278 	case STM32_I2S_CFG2_REG:
279 	case STM32_I2S_IER_REG:
280 	case STM32_I2S_SR_REG:
281 	case STM32_I2S_RXDR_REG:
282 	case STM32_I2S_CGFR_REG:
283 		return true;
284 	default:
285 		return false;
286 	}
287 }
288 
289 static bool stm32_i2s_volatile_reg(struct device *dev, unsigned int reg)
290 {
291 	switch (reg) {
292 	case STM32_I2S_SR_REG:
293 	case STM32_I2S_RXDR_REG:
294 		return true;
295 	default:
296 		return false;
297 	}
298 }
299 
300 static bool stm32_i2s_writeable_reg(struct device *dev, unsigned int reg)
301 {
302 	switch (reg) {
303 	case STM32_I2S_CR1_REG:
304 	case STM32_I2S_CFG1_REG:
305 	case STM32_I2S_CFG2_REG:
306 	case STM32_I2S_IER_REG:
307 	case STM32_I2S_IFCR_REG:
308 	case STM32_I2S_TXDR_REG:
309 	case STM32_I2S_CGFR_REG:
310 		return true;
311 	default:
312 		return false;
313 	}
314 }
315 
316 static int stm32_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
317 {
318 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
319 	u32 cgfr;
320 	u32 cgfr_mask =  I2S_CGFR_I2SSTD_MASK | I2S_CGFR_CKPOL |
321 			 I2S_CGFR_WSINV | I2S_CGFR_I2SCFG_MASK;
322 
323 	dev_dbg(cpu_dai->dev, "fmt %x\n", fmt);
324 
325 	/*
326 	 * winv = 0 : default behavior (high/low) for all standards
327 	 * ckpol = 0 for all standards.
328 	 */
329 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
330 	case SND_SOC_DAIFMT_I2S:
331 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_I2S);
332 		break;
333 	case SND_SOC_DAIFMT_MSB:
334 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_LEFT_J);
335 		break;
336 	case SND_SOC_DAIFMT_LSB:
337 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_RIGHT_J);
338 		break;
339 	case SND_SOC_DAIFMT_DSP_A:
340 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_DSP);
341 		break;
342 	/* DSP_B not mapped on I2S PCM long format. 1 bit offset does not fit */
343 	default:
344 		dev_err(cpu_dai->dev, "Unsupported protocol %#x\n",
345 			fmt & SND_SOC_DAIFMT_FORMAT_MASK);
346 		return -EINVAL;
347 	}
348 
349 	/* DAI clock strobing */
350 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
351 	case SND_SOC_DAIFMT_NB_NF:
352 		break;
353 	case SND_SOC_DAIFMT_IB_NF:
354 		cgfr |= I2S_CGFR_CKPOL;
355 		break;
356 	case SND_SOC_DAIFMT_NB_IF:
357 		cgfr |= I2S_CGFR_WSINV;
358 		break;
359 	case SND_SOC_DAIFMT_IB_IF:
360 		cgfr |= I2S_CGFR_CKPOL;
361 		cgfr |= I2S_CGFR_WSINV;
362 		break;
363 	default:
364 		dev_err(cpu_dai->dev, "Unsupported strobing %#x\n",
365 			fmt & SND_SOC_DAIFMT_INV_MASK);
366 		return -EINVAL;
367 	}
368 
369 	/* DAI clock master masks */
370 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
371 	case SND_SOC_DAIFMT_CBM_CFM:
372 		i2s->ms_flg = I2S_MS_SLAVE;
373 		break;
374 	case SND_SOC_DAIFMT_CBS_CFS:
375 		i2s->ms_flg = I2S_MS_MASTER;
376 		break;
377 	default:
378 		dev_err(cpu_dai->dev, "Unsupported mode %#x\n",
379 			fmt & SND_SOC_DAIFMT_MASTER_MASK);
380 		return -EINVAL;
381 	}
382 
383 	i2s->fmt = fmt;
384 	return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
385 				  cgfr_mask, cgfr);
386 }
387 
388 static int stm32_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
389 				int clk_id, unsigned int freq, int dir)
390 {
391 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
392 
393 	dev_dbg(cpu_dai->dev, "I2S MCLK frequency is %uHz\n", freq);
394 
395 	if ((dir == SND_SOC_CLOCK_OUT) && STM32_I2S_IS_MASTER(i2s)) {
396 		i2s->mclk_rate = freq;
397 
398 		/* Enable master clock if master mode and mclk-fs are set */
399 		return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
400 					  I2S_CGFR_MCKOE, I2S_CGFR_MCKOE);
401 	}
402 
403 	return 0;
404 }
405 
406 static int stm32_i2s_configure_clock(struct snd_soc_dai *cpu_dai,
407 				     struct snd_pcm_hw_params *params)
408 {
409 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
410 	unsigned long i2s_clock_rate;
411 	unsigned int tmp, div, real_div, nb_bits, frame_len;
412 	unsigned int rate = params_rate(params);
413 	int ret;
414 	u32 cgfr, cgfr_mask;
415 	bool odd;
416 
417 	if (!(rate % 11025))
418 		clk_set_parent(i2s->i2sclk, i2s->x11kclk);
419 	else
420 		clk_set_parent(i2s->i2sclk, i2s->x8kclk);
421 	i2s_clock_rate = clk_get_rate(i2s->i2sclk);
422 
423 	/*
424 	 * mckl = mclk_ratio x ws
425 	 *   i2s mode : mclk_ratio = 256
426 	 *   dsp mode : mclk_ratio = 128
427 	 *
428 	 * mclk on
429 	 *   i2s mode : div = i2s_clk / (mclk_ratio * ws)
430 	 *   dsp mode : div = i2s_clk / (mclk_ratio * ws)
431 	 * mclk off
432 	 *   i2s mode : div = i2s_clk / (nb_bits x ws)
433 	 *   dsp mode : div = i2s_clk / (nb_bits x ws)
434 	 */
435 	if (i2s->mclk_rate) {
436 		tmp = DIV_ROUND_CLOSEST(i2s_clock_rate, i2s->mclk_rate);
437 	} else {
438 		frame_len = 32;
439 		if ((i2s->fmt & SND_SOC_DAIFMT_FORMAT_MASK) ==
440 		    SND_SOC_DAIFMT_DSP_A)
441 			frame_len = 16;
442 
443 		/* master clock not enabled */
444 		ret = regmap_read(i2s->regmap, STM32_I2S_CGFR_REG, &cgfr);
445 		if (ret < 0)
446 			return ret;
447 
448 		nb_bits = frame_len * ((cgfr & I2S_CGFR_CHLEN) + 1);
449 		tmp = DIV_ROUND_CLOSEST(i2s_clock_rate, (nb_bits * rate));
450 	}
451 
452 	/* Check the parity of the divider */
453 	odd = tmp & 0x1;
454 
455 	/* Compute the div prescaler */
456 	div = tmp >> 1;
457 
458 	cgfr = I2S_CGFR_I2SDIV_SET(div) | (odd << I2S_CGFR_ODD_SHIFT);
459 	cgfr_mask = I2S_CGFR_I2SDIV_MASK | I2S_CGFR_ODD;
460 
461 	real_div = ((2 * div) + odd);
462 	dev_dbg(cpu_dai->dev, "I2S clk: %ld, SCLK: %d\n",
463 		i2s_clock_rate, rate);
464 	dev_dbg(cpu_dai->dev, "Divider: 2*%d(div)+%d(odd) = %d\n",
465 		div, odd, real_div);
466 
467 	if (((div == 1) && odd) || (div > I2S_CGFR_I2SDIV_MAX)) {
468 		dev_err(cpu_dai->dev, "Wrong divider setting\n");
469 		return -EINVAL;
470 	}
471 
472 	if (!div && !odd)
473 		dev_warn(cpu_dai->dev, "real divider forced to 1\n");
474 
475 	ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
476 				 cgfr_mask, cgfr);
477 	if (ret < 0)
478 		return ret;
479 
480 	/* Set bitclock and frameclock to their inactive state */
481 	return regmap_update_bits(i2s->regmap, STM32_I2S_CFG2_REG,
482 				  I2S_CFG2_AFCNTR, I2S_CFG2_AFCNTR);
483 }
484 
485 static int stm32_i2s_configure(struct snd_soc_dai *cpu_dai,
486 			       struct snd_pcm_hw_params *params,
487 			       struct snd_pcm_substream *substream)
488 {
489 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
490 	int format = params_width(params);
491 	u32 cfgr, cfgr_mask, cfg1;
492 	unsigned int fthlv;
493 	int ret;
494 
495 	switch (format) {
496 	case 16:
497 		cfgr = I2S_CGFR_DATLEN_SET(I2S_I2SMOD_DATLEN_16);
498 		cfgr_mask = I2S_CGFR_DATLEN_MASK | I2S_CGFR_CHLEN;
499 		break;
500 	case 32:
501 		cfgr = I2S_CGFR_DATLEN_SET(I2S_I2SMOD_DATLEN_32) |
502 					   I2S_CGFR_CHLEN;
503 		cfgr_mask = I2S_CGFR_DATLEN_MASK | I2S_CGFR_CHLEN;
504 		break;
505 	default:
506 		dev_err(cpu_dai->dev, "Unexpected format %d", format);
507 		return -EINVAL;
508 	}
509 
510 	if (STM32_I2S_IS_SLAVE(i2s)) {
511 		cfgr |= I2S_CGFR_I2SCFG_SET(I2S_I2SMOD_FD_SLAVE);
512 
513 		/* As data length is either 16 or 32 bits, fixch always set */
514 		cfgr |= I2S_CGFR_FIXCH;
515 		cfgr_mask |= I2S_CGFR_FIXCH;
516 	} else {
517 		cfgr |= I2S_CGFR_I2SCFG_SET(I2S_I2SMOD_FD_MASTER);
518 	}
519 	cfgr_mask |= I2S_CGFR_I2SCFG_MASK;
520 
521 	ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
522 				 cfgr_mask, cfgr);
523 	if (ret < 0)
524 		return ret;
525 
526 	fthlv = STM32_I2S_FIFO_SIZE * I2S_FIFO_TH_ONE_QUARTER / 4;
527 	cfg1 = I2S_CFG1_FTHVL_SET(fthlv - 1);
528 
529 	return regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
530 				  I2S_CFG1_FTHVL_MASK, cfg1);
531 }
532 
533 static int stm32_i2s_startup(struct snd_pcm_substream *substream,
534 			     struct snd_soc_dai *cpu_dai)
535 {
536 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
537 	unsigned long flags;
538 	int ret;
539 
540 	spin_lock_irqsave(&i2s->irq_lock, flags);
541 	i2s->substream = substream;
542 	spin_unlock_irqrestore(&i2s->irq_lock, flags);
543 
544 	if ((i2s->fmt & SND_SOC_DAIFMT_FORMAT_MASK) != SND_SOC_DAIFMT_DSP_A)
545 		snd_pcm_hw_constraint_single(substream->runtime,
546 					     SNDRV_PCM_HW_PARAM_CHANNELS, 2);
547 
548 	ret = clk_prepare_enable(i2s->i2sclk);
549 	if (ret < 0) {
550 		dev_err(cpu_dai->dev, "Failed to enable clock: %d\n", ret);
551 		return ret;
552 	}
553 
554 	return regmap_write_bits(i2s->regmap, STM32_I2S_IFCR_REG,
555 				 I2S_IFCR_MASK, I2S_IFCR_MASK);
556 }
557 
558 static int stm32_i2s_hw_params(struct snd_pcm_substream *substream,
559 			       struct snd_pcm_hw_params *params,
560 			       struct snd_soc_dai *cpu_dai)
561 {
562 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
563 	int ret;
564 
565 	ret = stm32_i2s_configure(cpu_dai, params, substream);
566 	if (ret < 0) {
567 		dev_err(cpu_dai->dev, "Configuration returned error %d\n", ret);
568 		return ret;
569 	}
570 
571 	if (STM32_I2S_IS_MASTER(i2s))
572 		ret = stm32_i2s_configure_clock(cpu_dai, params);
573 
574 	return ret;
575 }
576 
577 static int stm32_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
578 			     struct snd_soc_dai *cpu_dai)
579 {
580 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
581 	bool playback_flg = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK);
582 	u32 cfg1_mask, ier;
583 	int ret;
584 
585 	switch (cmd) {
586 	case SNDRV_PCM_TRIGGER_START:
587 	case SNDRV_PCM_TRIGGER_RESUME:
588 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
589 		/* Enable i2s */
590 		dev_dbg(cpu_dai->dev, "start I2S %s\n",
591 			playback_flg ? "playback" : "capture");
592 
593 		cfg1_mask = I2S_CFG1_RXDMAEN | I2S_CFG1_TXDMAEN;
594 		regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
595 				   cfg1_mask, cfg1_mask);
596 
597 		ret = regmap_update_bits(i2s->regmap, STM32_I2S_CR1_REG,
598 					 I2S_CR1_SPE, I2S_CR1_SPE);
599 		if (ret < 0) {
600 			dev_err(cpu_dai->dev, "Error %d enabling I2S\n", ret);
601 			return ret;
602 		}
603 
604 		ret = regmap_write_bits(i2s->regmap, STM32_I2S_CR1_REG,
605 					I2S_CR1_CSTART, I2S_CR1_CSTART);
606 		if (ret < 0) {
607 			dev_err(cpu_dai->dev, "Error %d starting I2S\n", ret);
608 			return ret;
609 		}
610 
611 		regmap_write_bits(i2s->regmap, STM32_I2S_IFCR_REG,
612 				  I2S_IFCR_MASK, I2S_IFCR_MASK);
613 
614 		spin_lock(&i2s->lock_fd);
615 		i2s->refcount++;
616 		if (playback_flg) {
617 			ier = I2S_IER_UDRIE;
618 		} else {
619 			ier = I2S_IER_OVRIE;
620 
621 			if (STM32_I2S_IS_MASTER(i2s) && i2s->refcount == 1)
622 				/* dummy write to gate bus clocks */
623 				regmap_write(i2s->regmap,
624 					     STM32_I2S_TXDR_REG, 0);
625 		}
626 		spin_unlock(&i2s->lock_fd);
627 
628 		if (STM32_I2S_IS_SLAVE(i2s))
629 			ier |= I2S_IER_TIFREIE;
630 
631 		regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG, ier, ier);
632 		break;
633 	case SNDRV_PCM_TRIGGER_STOP:
634 	case SNDRV_PCM_TRIGGER_SUSPEND:
635 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
636 		dev_dbg(cpu_dai->dev, "stop I2S %s\n",
637 			playback_flg ? "playback" : "capture");
638 
639 		if (playback_flg)
640 			regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG,
641 					   I2S_IER_UDRIE,
642 					   (unsigned int)~I2S_IER_UDRIE);
643 		else
644 			regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG,
645 					   I2S_IER_OVRIE,
646 					   (unsigned int)~I2S_IER_OVRIE);
647 
648 		spin_lock(&i2s->lock_fd);
649 		i2s->refcount--;
650 		if (i2s->refcount) {
651 			spin_unlock(&i2s->lock_fd);
652 			break;
653 		}
654 
655 		ret = regmap_update_bits(i2s->regmap, STM32_I2S_CR1_REG,
656 					 I2S_CR1_SPE, 0);
657 		if (ret < 0) {
658 			dev_err(cpu_dai->dev, "Error %d disabling I2S\n", ret);
659 			spin_unlock(&i2s->lock_fd);
660 			return ret;
661 		}
662 		spin_unlock(&i2s->lock_fd);
663 
664 		cfg1_mask = I2S_CFG1_RXDMAEN | I2S_CFG1_TXDMAEN;
665 		regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
666 				   cfg1_mask, 0);
667 		break;
668 	default:
669 		return -EINVAL;
670 	}
671 
672 	return 0;
673 }
674 
675 static void stm32_i2s_shutdown(struct snd_pcm_substream *substream,
676 			       struct snd_soc_dai *cpu_dai)
677 {
678 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
679 	unsigned long flags;
680 
681 	regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
682 			   I2S_CGFR_MCKOE, (unsigned int)~I2S_CGFR_MCKOE);
683 
684 	clk_disable_unprepare(i2s->i2sclk);
685 
686 	spin_lock_irqsave(&i2s->irq_lock, flags);
687 	i2s->substream = NULL;
688 	spin_unlock_irqrestore(&i2s->irq_lock, flags);
689 }
690 
691 static int stm32_i2s_dai_probe(struct snd_soc_dai *cpu_dai)
692 {
693 	struct stm32_i2s_data *i2s = dev_get_drvdata(cpu_dai->dev);
694 	struct snd_dmaengine_dai_dma_data *dma_data_tx = &i2s->dma_data_tx;
695 	struct snd_dmaengine_dai_dma_data *dma_data_rx = &i2s->dma_data_rx;
696 
697 	/* Buswidth will be set by framework */
698 	dma_data_tx->addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
699 	dma_data_tx->addr = (dma_addr_t)(i2s->phys_addr) + STM32_I2S_TXDR_REG;
700 	dma_data_tx->maxburst = 1;
701 	dma_data_rx->addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
702 	dma_data_rx->addr = (dma_addr_t)(i2s->phys_addr) + STM32_I2S_RXDR_REG;
703 	dma_data_rx->maxburst = 1;
704 
705 	snd_soc_dai_init_dma_data(cpu_dai, dma_data_tx, dma_data_rx);
706 
707 	return 0;
708 }
709 
710 static const struct regmap_config stm32_h7_i2s_regmap_conf = {
711 	.reg_bits = 32,
712 	.reg_stride = 4,
713 	.val_bits = 32,
714 	.max_register = STM32_I2S_CGFR_REG,
715 	.readable_reg = stm32_i2s_readable_reg,
716 	.volatile_reg = stm32_i2s_volatile_reg,
717 	.writeable_reg = stm32_i2s_writeable_reg,
718 	.fast_io = true,
719 	.cache_type = REGCACHE_FLAT,
720 };
721 
722 static const struct snd_soc_dai_ops stm32_i2s_pcm_dai_ops = {
723 	.set_sysclk	= stm32_i2s_set_sysclk,
724 	.set_fmt	= stm32_i2s_set_dai_fmt,
725 	.startup	= stm32_i2s_startup,
726 	.hw_params	= stm32_i2s_hw_params,
727 	.trigger	= stm32_i2s_trigger,
728 	.shutdown	= stm32_i2s_shutdown,
729 };
730 
731 static const struct snd_pcm_hardware stm32_i2s_pcm_hw = {
732 	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_MMAP,
733 	.buffer_bytes_max = 8 * PAGE_SIZE,
734 	.period_bytes_min = 1024,
735 	.period_bytes_max = 4 * PAGE_SIZE,
736 	.periods_min = 2,
737 	.periods_max = 8,
738 };
739 
740 static const struct snd_dmaengine_pcm_config stm32_i2s_pcm_config = {
741 	.pcm_hardware	= &stm32_i2s_pcm_hw,
742 	.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
743 	.prealloc_buffer_size = PAGE_SIZE * 8,
744 };
745 
746 static const struct snd_soc_component_driver stm32_i2s_component = {
747 	.name = "stm32-i2s",
748 };
749 
750 static void stm32_i2s_dai_init(struct snd_soc_pcm_stream *stream,
751 			       char *stream_name)
752 {
753 	stream->stream_name = stream_name;
754 	stream->channels_min = 1;
755 	stream->channels_max = 2;
756 	stream->rates = SNDRV_PCM_RATE_8000_192000;
757 	stream->formats = SNDRV_PCM_FMTBIT_S16_LE |
758 				   SNDRV_PCM_FMTBIT_S32_LE;
759 }
760 
761 static int stm32_i2s_dais_init(struct platform_device *pdev,
762 			       struct stm32_i2s_data *i2s)
763 {
764 	struct snd_soc_dai_driver *dai_ptr;
765 
766 	dai_ptr = devm_kzalloc(&pdev->dev, sizeof(struct snd_soc_dai_driver),
767 			       GFP_KERNEL);
768 	if (!dai_ptr)
769 		return -ENOMEM;
770 
771 	dai_ptr->probe = stm32_i2s_dai_probe;
772 	dai_ptr->ops = &stm32_i2s_pcm_dai_ops;
773 	dai_ptr->id = 1;
774 	stm32_i2s_dai_init(&dai_ptr->playback, "playback");
775 	stm32_i2s_dai_init(&dai_ptr->capture, "capture");
776 	i2s->dai_drv = dai_ptr;
777 
778 	return 0;
779 }
780 
781 static const struct of_device_id stm32_i2s_ids[] = {
782 	{
783 		.compatible = "st,stm32h7-i2s",
784 		.data = &stm32_h7_i2s_regmap_conf
785 	},
786 	{},
787 };
788 
789 static int stm32_i2s_parse_dt(struct platform_device *pdev,
790 			      struct stm32_i2s_data *i2s)
791 {
792 	struct device_node *np = pdev->dev.of_node;
793 	const struct of_device_id *of_id;
794 	struct reset_control *rst;
795 	struct resource *res;
796 	int irq, ret;
797 
798 	if (!np)
799 		return -ENODEV;
800 
801 	of_id = of_match_device(stm32_i2s_ids, &pdev->dev);
802 	if (of_id)
803 		i2s->regmap_conf = (const struct regmap_config *)of_id->data;
804 	else
805 		return -EINVAL;
806 
807 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
808 	i2s->base = devm_ioremap_resource(&pdev->dev, res);
809 	if (IS_ERR(i2s->base))
810 		return PTR_ERR(i2s->base);
811 
812 	i2s->phys_addr = res->start;
813 
814 	/* Get clocks */
815 	i2s->pclk = devm_clk_get(&pdev->dev, "pclk");
816 	if (IS_ERR(i2s->pclk)) {
817 		dev_err(&pdev->dev, "Could not get pclk\n");
818 		return PTR_ERR(i2s->pclk);
819 	}
820 
821 	i2s->i2sclk = devm_clk_get(&pdev->dev, "i2sclk");
822 	if (IS_ERR(i2s->i2sclk)) {
823 		dev_err(&pdev->dev, "Could not get i2sclk\n");
824 		return PTR_ERR(i2s->i2sclk);
825 	}
826 
827 	i2s->x8kclk = devm_clk_get(&pdev->dev, "x8k");
828 	if (IS_ERR(i2s->x8kclk)) {
829 		dev_err(&pdev->dev, "missing x8k parent clock\n");
830 		return PTR_ERR(i2s->x8kclk);
831 	}
832 
833 	i2s->x11kclk = devm_clk_get(&pdev->dev, "x11k");
834 	if (IS_ERR(i2s->x11kclk)) {
835 		dev_err(&pdev->dev, "missing x11k parent clock\n");
836 		return PTR_ERR(i2s->x11kclk);
837 	}
838 
839 	/* Get irqs */
840 	irq = platform_get_irq(pdev, 0);
841 	if (irq < 0) {
842 		if (irq != -EPROBE_DEFER)
843 			dev_err(&pdev->dev, "no irq for node %s\n", pdev->name);
844 		return irq;
845 	}
846 
847 	ret = devm_request_irq(&pdev->dev, irq, stm32_i2s_isr, IRQF_ONESHOT,
848 			       dev_name(&pdev->dev), i2s);
849 	if (ret) {
850 		dev_err(&pdev->dev, "irq request returned %d\n", ret);
851 		return ret;
852 	}
853 
854 	/* Reset */
855 	rst = devm_reset_control_get_exclusive(&pdev->dev, NULL);
856 	if (!IS_ERR(rst)) {
857 		reset_control_assert(rst);
858 		udelay(2);
859 		reset_control_deassert(rst);
860 	}
861 
862 	return 0;
863 }
864 
865 static int stm32_i2s_probe(struct platform_device *pdev)
866 {
867 	struct stm32_i2s_data *i2s;
868 	int ret;
869 
870 	i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
871 	if (!i2s)
872 		return -ENOMEM;
873 
874 	ret = stm32_i2s_parse_dt(pdev, i2s);
875 	if (ret)
876 		return ret;
877 
878 	i2s->pdev = pdev;
879 	i2s->ms_flg = I2S_MS_NOT_SET;
880 	spin_lock_init(&i2s->lock_fd);
881 	spin_lock_init(&i2s->irq_lock);
882 	platform_set_drvdata(pdev, i2s);
883 
884 	ret = stm32_i2s_dais_init(pdev, i2s);
885 	if (ret)
886 		return ret;
887 
888 	i2s->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "pclk",
889 						i2s->base, i2s->regmap_conf);
890 	if (IS_ERR(i2s->regmap)) {
891 		dev_err(&pdev->dev, "regmap init failed\n");
892 		return PTR_ERR(i2s->regmap);
893 	}
894 
895 	ret = devm_snd_soc_register_component(&pdev->dev, &stm32_i2s_component,
896 					      i2s->dai_drv, 1);
897 	if (ret)
898 		return ret;
899 
900 	ret = devm_snd_dmaengine_pcm_register(&pdev->dev,
901 					      &stm32_i2s_pcm_config, 0);
902 	if (ret)
903 		return ret;
904 
905 	/* Set SPI/I2S in i2s mode */
906 	return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
907 				  I2S_CGFR_I2SMOD, I2S_CGFR_I2SMOD);
908 }
909 
910 MODULE_DEVICE_TABLE(of, stm32_i2s_ids);
911 
912 #ifdef CONFIG_PM_SLEEP
913 static int stm32_i2s_suspend(struct device *dev)
914 {
915 	struct stm32_i2s_data *i2s = dev_get_drvdata(dev);
916 
917 	regcache_cache_only(i2s->regmap, true);
918 	regcache_mark_dirty(i2s->regmap);
919 
920 	return 0;
921 }
922 
923 static int stm32_i2s_resume(struct device *dev)
924 {
925 	struct stm32_i2s_data *i2s = dev_get_drvdata(dev);
926 
927 	regcache_cache_only(i2s->regmap, false);
928 	return regcache_sync(i2s->regmap);
929 }
930 #endif /* CONFIG_PM_SLEEP */
931 
932 static const struct dev_pm_ops stm32_i2s_pm_ops = {
933 	SET_SYSTEM_SLEEP_PM_OPS(stm32_i2s_suspend, stm32_i2s_resume)
934 };
935 
936 static struct platform_driver stm32_i2s_driver = {
937 	.driver = {
938 		.name = "st,stm32-i2s",
939 		.of_match_table = stm32_i2s_ids,
940 		.pm = &stm32_i2s_pm_ops,
941 	},
942 	.probe = stm32_i2s_probe,
943 };
944 
945 module_platform_driver(stm32_i2s_driver);
946 
947 MODULE_DESCRIPTION("STM32 Soc i2s Interface");
948 MODULE_AUTHOR("Olivier Moysan, <olivier.moysan@st.com>");
949 MODULE_ALIAS("platform:stm32-i2s");
950 MODULE_LICENSE("GPL v2");
951