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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_DAI_NAME_SIZE		20
183 #define STM32_I2S_FIFO_SIZE		16
184 
185 #define STM32_I2S_IS_MASTER(x)		((x)->ms_flg == I2S_MS_MASTER)
186 #define STM32_I2S_IS_SLAVE(x)		((x)->ms_flg == I2S_MS_SLAVE)
187 
188 /**
189  * @regmap_conf: I2S register map configuration pointer
190  * @egmap: 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  * @dais_name: DAI name
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 	char dais_name[STM32_I2S_DAI_NAME_SIZE];
225 	unsigned int mclk_rate;
226 	unsigned int fmt;
227 	int refcount;
228 	int ms_flg;
229 };
230 
stm32_i2s_isr(int irq,void * devid)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 	if (err)
266 		snd_pcm_stop_xrun(i2s->substream);
267 
268 	return IRQ_HANDLED;
269 }
270 
stm32_i2s_readable_reg(struct device * dev,unsigned int reg)271 static bool stm32_i2s_readable_reg(struct device *dev, unsigned int reg)
272 {
273 	switch (reg) {
274 	case STM32_I2S_CR1_REG:
275 	case STM32_I2S_CFG1_REG:
276 	case STM32_I2S_CFG2_REG:
277 	case STM32_I2S_IER_REG:
278 	case STM32_I2S_SR_REG:
279 	case STM32_I2S_TXDR_REG:
280 	case STM32_I2S_RXDR_REG:
281 	case STM32_I2S_CGFR_REG:
282 		return true;
283 	default:
284 		return false;
285 	}
286 }
287 
stm32_i2s_volatile_reg(struct device * dev,unsigned int reg)288 static bool stm32_i2s_volatile_reg(struct device *dev, unsigned int reg)
289 {
290 	switch (reg) {
291 	case STM32_I2S_TXDR_REG:
292 	case STM32_I2S_RXDR_REG:
293 		return true;
294 	default:
295 		return false;
296 	}
297 }
298 
stm32_i2s_writeable_reg(struct device * dev,unsigned int reg)299 static bool stm32_i2s_writeable_reg(struct device *dev, unsigned int reg)
300 {
301 	switch (reg) {
302 	case STM32_I2S_CR1_REG:
303 	case STM32_I2S_CFG1_REG:
304 	case STM32_I2S_CFG2_REG:
305 	case STM32_I2S_IER_REG:
306 	case STM32_I2S_IFCR_REG:
307 	case STM32_I2S_TXDR_REG:
308 	case STM32_I2S_CGFR_REG:
309 		return true;
310 	default:
311 		return false;
312 	}
313 }
314 
stm32_i2s_set_dai_fmt(struct snd_soc_dai * cpu_dai,unsigned int fmt)315 static int stm32_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
316 {
317 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
318 	u32 cgfr;
319 	u32 cgfr_mask =  I2S_CGFR_I2SSTD_MASK | I2S_CGFR_CKPOL |
320 			 I2S_CGFR_WSINV | I2S_CGFR_I2SCFG_MASK;
321 
322 	dev_dbg(cpu_dai->dev, "fmt %x\n", fmt);
323 
324 	/*
325 	 * winv = 0 : default behavior (high/low) for all standards
326 	 * ckpol = 0 for all standards.
327 	 */
328 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
329 	case SND_SOC_DAIFMT_I2S:
330 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_I2S);
331 		break;
332 	case SND_SOC_DAIFMT_MSB:
333 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_LEFT_J);
334 		break;
335 	case SND_SOC_DAIFMT_LSB:
336 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_RIGHT_J);
337 		break;
338 	case SND_SOC_DAIFMT_DSP_A:
339 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_DSP);
340 		break;
341 	/* DSP_B not mapped on I2S PCM long format. 1 bit offset does not fit */
342 	default:
343 		dev_err(cpu_dai->dev, "Unsupported protocol %#x\n",
344 			fmt & SND_SOC_DAIFMT_FORMAT_MASK);
345 		return -EINVAL;
346 	}
347 
348 	/* DAI clock strobing */
349 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
350 	case SND_SOC_DAIFMT_NB_NF:
351 		break;
352 	case SND_SOC_DAIFMT_IB_NF:
353 		cgfr |= I2S_CGFR_CKPOL;
354 		break;
355 	case SND_SOC_DAIFMT_NB_IF:
356 		cgfr |= I2S_CGFR_WSINV;
357 		break;
358 	case SND_SOC_DAIFMT_IB_IF:
359 		cgfr |= I2S_CGFR_CKPOL;
360 		cgfr |= I2S_CGFR_WSINV;
361 		break;
362 	default:
363 		dev_err(cpu_dai->dev, "Unsupported strobing %#x\n",
364 			fmt & SND_SOC_DAIFMT_INV_MASK);
365 		return -EINVAL;
366 	}
367 
368 	/* DAI clock master masks */
369 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
370 	case SND_SOC_DAIFMT_CBM_CFM:
371 		i2s->ms_flg = I2S_MS_SLAVE;
372 		break;
373 	case SND_SOC_DAIFMT_CBS_CFS:
374 		i2s->ms_flg = I2S_MS_MASTER;
375 		break;
376 	default:
377 		dev_err(cpu_dai->dev, "Unsupported mode %#x\n",
378 			fmt & SND_SOC_DAIFMT_MASTER_MASK);
379 		return -EINVAL;
380 	}
381 
382 	i2s->fmt = fmt;
383 	return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
384 				  cgfr_mask, cgfr);
385 }
386 
stm32_i2s_set_sysclk(struct snd_soc_dai * cpu_dai,int clk_id,unsigned int freq,int dir)387 static int stm32_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
388 				int clk_id, unsigned int freq, int dir)
389 {
390 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
391 
392 	dev_dbg(cpu_dai->dev, "I2S MCLK frequency is %uHz\n", freq);
393 
394 	if ((dir == SND_SOC_CLOCK_OUT) && STM32_I2S_IS_MASTER(i2s)) {
395 		i2s->mclk_rate = freq;
396 
397 		/* Enable master clock if master mode and mclk-fs are set */
398 		return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
399 					  I2S_CGFR_MCKOE, I2S_CGFR_MCKOE);
400 	}
401 
402 	return 0;
403 }
404 
stm32_i2s_configure_clock(struct snd_soc_dai * cpu_dai,struct snd_pcm_hw_params * params)405 static int stm32_i2s_configure_clock(struct snd_soc_dai *cpu_dai,
406 				     struct snd_pcm_hw_params *params)
407 {
408 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
409 	unsigned long i2s_clock_rate;
410 	unsigned int tmp, div, real_div, nb_bits, frame_len;
411 	unsigned int rate = params_rate(params);
412 	int ret;
413 	u32 cgfr, cgfr_mask;
414 	bool odd;
415 
416 	if (!(rate % 11025))
417 		clk_set_parent(i2s->i2sclk, i2s->x11kclk);
418 	else
419 		clk_set_parent(i2s->i2sclk, i2s->x8kclk);
420 	i2s_clock_rate = clk_get_rate(i2s->i2sclk);
421 
422 	/*
423 	 * mckl = mclk_ratio x ws
424 	 *   i2s mode : mclk_ratio = 256
425 	 *   dsp mode : mclk_ratio = 128
426 	 *
427 	 * mclk on
428 	 *   i2s mode : div = i2s_clk / (mclk_ratio * ws)
429 	 *   dsp mode : div = i2s_clk / (mclk_ratio * ws)
430 	 * mclk off
431 	 *   i2s mode : div = i2s_clk / (nb_bits x ws)
432 	 *   dsp mode : div = i2s_clk / (nb_bits x ws)
433 	 */
434 	if (i2s->mclk_rate) {
435 		tmp = DIV_ROUND_CLOSEST(i2s_clock_rate, i2s->mclk_rate);
436 	} else {
437 		frame_len = 32;
438 		if ((i2s->fmt & SND_SOC_DAIFMT_FORMAT_MASK) ==
439 		    SND_SOC_DAIFMT_DSP_A)
440 			frame_len = 16;
441 
442 		/* master clock not enabled */
443 		ret = regmap_read(i2s->regmap, STM32_I2S_CGFR_REG, &cgfr);
444 		if (ret < 0)
445 			return ret;
446 
447 		nb_bits = frame_len * ((cgfr & I2S_CGFR_CHLEN) + 1);
448 		tmp = DIV_ROUND_CLOSEST(i2s_clock_rate, (nb_bits * rate));
449 	}
450 
451 	/* Check the parity of the divider */
452 	odd = tmp & 0x1;
453 
454 	/* Compute the div prescaler */
455 	div = tmp >> 1;
456 
457 	cgfr = I2S_CGFR_I2SDIV_SET(div) | (odd << I2S_CGFR_ODD_SHIFT);
458 	cgfr_mask = I2S_CGFR_I2SDIV_MASK | I2S_CGFR_ODD;
459 
460 	real_div = ((2 * div) + odd);
461 	dev_dbg(cpu_dai->dev, "I2S clk: %ld, SCLK: %d\n",
462 		i2s_clock_rate, rate);
463 	dev_dbg(cpu_dai->dev, "Divider: 2*%d(div)+%d(odd) = %d\n",
464 		div, odd, real_div);
465 
466 	if (((div == 1) && odd) || (div > I2S_CGFR_I2SDIV_MAX)) {
467 		dev_err(cpu_dai->dev, "Wrong divider setting\n");
468 		return -EINVAL;
469 	}
470 
471 	if (!div && !odd)
472 		dev_warn(cpu_dai->dev, "real divider forced to 1\n");
473 
474 	ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
475 				 cgfr_mask, cgfr);
476 	if (ret < 0)
477 		return ret;
478 
479 	/* Set bitclock and frameclock to their inactive state */
480 	return regmap_update_bits(i2s->regmap, STM32_I2S_CFG2_REG,
481 				  I2S_CFG2_AFCNTR, I2S_CFG2_AFCNTR);
482 }
483 
stm32_i2s_configure(struct snd_soc_dai * cpu_dai,struct snd_pcm_hw_params * params,struct snd_pcm_substream * substream)484 static int stm32_i2s_configure(struct snd_soc_dai *cpu_dai,
485 			       struct snd_pcm_hw_params *params,
486 			       struct snd_pcm_substream *substream)
487 {
488 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
489 	int format = params_width(params);
490 	u32 cfgr, cfgr_mask, cfg1;
491 	unsigned int fthlv;
492 	int ret;
493 
494 	if ((params_channels(params) == 1) &&
495 	    ((i2s->fmt & SND_SOC_DAIFMT_FORMAT_MASK) != SND_SOC_DAIFMT_DSP_A)) {
496 		dev_err(cpu_dai->dev, "Mono mode supported only by DSP_A\n");
497 		return -EINVAL;
498 	}
499 
500 	switch (format) {
501 	case 16:
502 		cfgr = I2S_CGFR_DATLEN_SET(I2S_I2SMOD_DATLEN_16);
503 		cfgr_mask = I2S_CGFR_DATLEN_MASK | I2S_CGFR_CHLEN;
504 		break;
505 	case 32:
506 		cfgr = I2S_CGFR_DATLEN_SET(I2S_I2SMOD_DATLEN_32) |
507 					   I2S_CGFR_CHLEN;
508 		cfgr_mask = I2S_CGFR_DATLEN_MASK | I2S_CGFR_CHLEN;
509 		break;
510 	default:
511 		dev_err(cpu_dai->dev, "Unexpected format %d", format);
512 		return -EINVAL;
513 	}
514 
515 	if (STM32_I2S_IS_SLAVE(i2s)) {
516 		cfgr |= I2S_CGFR_I2SCFG_SET(I2S_I2SMOD_FD_SLAVE);
517 
518 		/* As data length is either 16 or 32 bits, fixch always set */
519 		cfgr |= I2S_CGFR_FIXCH;
520 		cfgr_mask |= I2S_CGFR_FIXCH;
521 	} else {
522 		cfgr |= I2S_CGFR_I2SCFG_SET(I2S_I2SMOD_FD_MASTER);
523 	}
524 	cfgr_mask |= I2S_CGFR_I2SCFG_MASK;
525 
526 	ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
527 				 cfgr_mask, cfgr);
528 	if (ret < 0)
529 		return ret;
530 
531 	fthlv = STM32_I2S_FIFO_SIZE * I2S_FIFO_TH_ONE_QUARTER / 4;
532 	cfg1 = I2S_CFG1_FTHVL_SET(fthlv - 1);
533 
534 	return regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
535 				  I2S_CFG1_FTHVL_MASK, cfg1);
536 }
537 
stm32_i2s_startup(struct snd_pcm_substream * substream,struct snd_soc_dai * cpu_dai)538 static int stm32_i2s_startup(struct snd_pcm_substream *substream,
539 			     struct snd_soc_dai *cpu_dai)
540 {
541 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
542 
543 	i2s->substream = substream;
544 
545 	spin_lock(&i2s->lock_fd);
546 	i2s->refcount++;
547 	spin_unlock(&i2s->lock_fd);
548 
549 	return regmap_write_bits(i2s->regmap, STM32_I2S_IFCR_REG,
550 				 I2S_IFCR_MASK, I2S_IFCR_MASK);
551 }
552 
stm32_i2s_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params,struct snd_soc_dai * cpu_dai)553 static int stm32_i2s_hw_params(struct snd_pcm_substream *substream,
554 			       struct snd_pcm_hw_params *params,
555 			       struct snd_soc_dai *cpu_dai)
556 {
557 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
558 	int ret;
559 
560 	ret = stm32_i2s_configure(cpu_dai, params, substream);
561 	if (ret < 0) {
562 		dev_err(cpu_dai->dev, "Configuration returned error %d\n", ret);
563 		return ret;
564 	}
565 
566 	if (STM32_I2S_IS_MASTER(i2s))
567 		ret = stm32_i2s_configure_clock(cpu_dai, params);
568 
569 	return ret;
570 }
571 
stm32_i2s_trigger(struct snd_pcm_substream * substream,int cmd,struct snd_soc_dai * cpu_dai)572 static int stm32_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
573 			     struct snd_soc_dai *cpu_dai)
574 {
575 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
576 	bool playback_flg = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK);
577 	u32 cfg1_mask, ier;
578 	int ret;
579 
580 	switch (cmd) {
581 	case SNDRV_PCM_TRIGGER_START:
582 	case SNDRV_PCM_TRIGGER_RESUME:
583 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
584 		/* Enable i2s */
585 		dev_dbg(cpu_dai->dev, "start I2S\n");
586 
587 		cfg1_mask = I2S_CFG1_RXDMAEN | I2S_CFG1_TXDMAEN;
588 		regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
589 				   cfg1_mask, cfg1_mask);
590 
591 		ret = regmap_update_bits(i2s->regmap, STM32_I2S_CR1_REG,
592 					 I2S_CR1_SPE, I2S_CR1_SPE);
593 		if (ret < 0) {
594 			dev_err(cpu_dai->dev, "Error %d enabling I2S\n", ret);
595 			return ret;
596 		}
597 
598 		ret = regmap_update_bits(i2s->regmap, STM32_I2S_CR1_REG,
599 					 I2S_CR1_CSTART, I2S_CR1_CSTART);
600 		if (ret < 0) {
601 			dev_err(cpu_dai->dev, "Error %d starting I2S\n", ret);
602 			return ret;
603 		}
604 
605 		regmap_write_bits(i2s->regmap, STM32_I2S_IFCR_REG,
606 				  I2S_IFCR_MASK, I2S_IFCR_MASK);
607 
608 		if (playback_flg) {
609 			ier = I2S_IER_UDRIE;
610 		} else {
611 			ier = I2S_IER_OVRIE;
612 
613 			spin_lock(&i2s->lock_fd);
614 			if (i2s->refcount == 1)
615 				/* dummy write to trigger capture */
616 				regmap_write(i2s->regmap,
617 					     STM32_I2S_TXDR_REG, 0);
618 			spin_unlock(&i2s->lock_fd);
619 		}
620 
621 		if (STM32_I2S_IS_SLAVE(i2s))
622 			ier |= I2S_IER_TIFREIE;
623 
624 		regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG, ier, ier);
625 		break;
626 	case SNDRV_PCM_TRIGGER_STOP:
627 	case SNDRV_PCM_TRIGGER_SUSPEND:
628 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
629 		if (playback_flg)
630 			regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG,
631 					   I2S_IER_UDRIE,
632 					   (unsigned int)~I2S_IER_UDRIE);
633 		else
634 			regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG,
635 					   I2S_IER_OVRIE,
636 					   (unsigned int)~I2S_IER_OVRIE);
637 
638 		spin_lock(&i2s->lock_fd);
639 		i2s->refcount--;
640 		if (i2s->refcount) {
641 			spin_unlock(&i2s->lock_fd);
642 			break;
643 		}
644 		spin_unlock(&i2s->lock_fd);
645 
646 		dev_dbg(cpu_dai->dev, "stop I2S\n");
647 
648 		ret = regmap_update_bits(i2s->regmap, STM32_I2S_CR1_REG,
649 					 I2S_CR1_SPE, 0);
650 		if (ret < 0) {
651 			dev_err(cpu_dai->dev, "Error %d disabling I2S\n", ret);
652 			return ret;
653 		}
654 
655 		cfg1_mask = I2S_CFG1_RXDMAEN | I2S_CFG1_TXDMAEN;
656 		regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
657 				   cfg1_mask, 0);
658 		break;
659 	default:
660 		return -EINVAL;
661 	}
662 
663 	return 0;
664 }
665 
stm32_i2s_shutdown(struct snd_pcm_substream * substream,struct snd_soc_dai * cpu_dai)666 static void stm32_i2s_shutdown(struct snd_pcm_substream *substream,
667 			       struct snd_soc_dai *cpu_dai)
668 {
669 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
670 
671 	i2s->substream = NULL;
672 
673 	regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
674 			   I2S_CGFR_MCKOE, (unsigned int)~I2S_CGFR_MCKOE);
675 }
676 
stm32_i2s_dai_probe(struct snd_soc_dai * cpu_dai)677 static int stm32_i2s_dai_probe(struct snd_soc_dai *cpu_dai)
678 {
679 	struct stm32_i2s_data *i2s = dev_get_drvdata(cpu_dai->dev);
680 	struct snd_dmaengine_dai_dma_data *dma_data_tx = &i2s->dma_data_tx;
681 	struct snd_dmaengine_dai_dma_data *dma_data_rx = &i2s->dma_data_rx;
682 
683 	/* Buswidth will be set by framework */
684 	dma_data_tx->addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
685 	dma_data_tx->addr = (dma_addr_t)(i2s->phys_addr) + STM32_I2S_TXDR_REG;
686 	dma_data_tx->maxburst = 1;
687 	dma_data_rx->addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
688 	dma_data_rx->addr = (dma_addr_t)(i2s->phys_addr) + STM32_I2S_RXDR_REG;
689 	dma_data_rx->maxburst = 1;
690 
691 	snd_soc_dai_init_dma_data(cpu_dai, dma_data_tx, dma_data_rx);
692 
693 	return 0;
694 }
695 
696 static const struct regmap_config stm32_h7_i2s_regmap_conf = {
697 	.reg_bits = 32,
698 	.reg_stride = 4,
699 	.val_bits = 32,
700 	.max_register = STM32_I2S_CGFR_REG,
701 	.readable_reg = stm32_i2s_readable_reg,
702 	.volatile_reg = stm32_i2s_volatile_reg,
703 	.writeable_reg = stm32_i2s_writeable_reg,
704 	.fast_io = true,
705 };
706 
707 static const struct snd_soc_dai_ops stm32_i2s_pcm_dai_ops = {
708 	.set_sysclk	= stm32_i2s_set_sysclk,
709 	.set_fmt	= stm32_i2s_set_dai_fmt,
710 	.startup	= stm32_i2s_startup,
711 	.hw_params	= stm32_i2s_hw_params,
712 	.trigger	= stm32_i2s_trigger,
713 	.shutdown	= stm32_i2s_shutdown,
714 };
715 
716 static const struct snd_pcm_hardware stm32_i2s_pcm_hw = {
717 	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_MMAP,
718 	.buffer_bytes_max = 8 * PAGE_SIZE,
719 	.period_bytes_max = 2048,
720 	.periods_min = 2,
721 	.periods_max = 8,
722 };
723 
724 static const struct snd_dmaengine_pcm_config stm32_i2s_pcm_config = {
725 	.pcm_hardware	= &stm32_i2s_pcm_hw,
726 	.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
727 	.prealloc_buffer_size = PAGE_SIZE * 8,
728 };
729 
730 static const struct snd_soc_component_driver stm32_i2s_component = {
731 	.name = "stm32-i2s",
732 };
733 
stm32_i2s_dai_init(struct snd_soc_pcm_stream * stream,char * stream_name)734 static void stm32_i2s_dai_init(struct snd_soc_pcm_stream *stream,
735 			       char *stream_name)
736 {
737 	stream->stream_name = stream_name;
738 	stream->channels_min = 1;
739 	stream->channels_max = 2;
740 	stream->rates = SNDRV_PCM_RATE_8000_192000;
741 	stream->formats = SNDRV_PCM_FMTBIT_S16_LE |
742 				   SNDRV_PCM_FMTBIT_S32_LE;
743 }
744 
stm32_i2s_dais_init(struct platform_device * pdev,struct stm32_i2s_data * i2s)745 static int stm32_i2s_dais_init(struct platform_device *pdev,
746 			       struct stm32_i2s_data *i2s)
747 {
748 	struct snd_soc_dai_driver *dai_ptr;
749 
750 	dai_ptr = devm_kzalloc(&pdev->dev, sizeof(struct snd_soc_dai_driver),
751 			       GFP_KERNEL);
752 	if (!dai_ptr)
753 		return -ENOMEM;
754 
755 	snprintf(i2s->dais_name, STM32_I2S_DAI_NAME_SIZE,
756 		 "%s", dev_name(&pdev->dev));
757 
758 	dai_ptr->probe = stm32_i2s_dai_probe;
759 	dai_ptr->ops = &stm32_i2s_pcm_dai_ops;
760 	dai_ptr->name = i2s->dais_name;
761 	dai_ptr->id = 1;
762 	stm32_i2s_dai_init(&dai_ptr->playback, "playback");
763 	stm32_i2s_dai_init(&dai_ptr->capture, "capture");
764 	i2s->dai_drv = dai_ptr;
765 
766 	return 0;
767 }
768 
769 static const struct of_device_id stm32_i2s_ids[] = {
770 	{
771 		.compatible = "st,stm32h7-i2s",
772 		.data = &stm32_h7_i2s_regmap_conf
773 	},
774 	{},
775 };
776 
stm32_i2s_parse_dt(struct platform_device * pdev,struct stm32_i2s_data * i2s)777 static int stm32_i2s_parse_dt(struct platform_device *pdev,
778 			      struct stm32_i2s_data *i2s)
779 {
780 	struct device_node *np = pdev->dev.of_node;
781 	const struct of_device_id *of_id;
782 	struct reset_control *rst;
783 	struct resource *res;
784 	int irq, ret;
785 
786 	if (!np)
787 		return -ENODEV;
788 
789 	of_id = of_match_device(stm32_i2s_ids, &pdev->dev);
790 	if (of_id)
791 		i2s->regmap_conf = (const struct regmap_config *)of_id->data;
792 	else
793 		return -EINVAL;
794 
795 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
796 	i2s->base = devm_ioremap_resource(&pdev->dev, res);
797 	if (IS_ERR(i2s->base))
798 		return PTR_ERR(i2s->base);
799 
800 	i2s->phys_addr = res->start;
801 
802 	/* Get clocks */
803 	i2s->pclk = devm_clk_get(&pdev->dev, "pclk");
804 	if (IS_ERR(i2s->pclk)) {
805 		dev_err(&pdev->dev, "Could not get pclk\n");
806 		return PTR_ERR(i2s->pclk);
807 	}
808 
809 	i2s->i2sclk = devm_clk_get(&pdev->dev, "i2sclk");
810 	if (IS_ERR(i2s->i2sclk)) {
811 		dev_err(&pdev->dev, "Could not get i2sclk\n");
812 		return PTR_ERR(i2s->i2sclk);
813 	}
814 
815 	i2s->x8kclk = devm_clk_get(&pdev->dev, "x8k");
816 	if (IS_ERR(i2s->x8kclk)) {
817 		dev_err(&pdev->dev, "missing x8k parent clock\n");
818 		return PTR_ERR(i2s->x8kclk);
819 	}
820 
821 	i2s->x11kclk = devm_clk_get(&pdev->dev, "x11k");
822 	if (IS_ERR(i2s->x11kclk)) {
823 		dev_err(&pdev->dev, "missing x11k parent clock\n");
824 		return PTR_ERR(i2s->x11kclk);
825 	}
826 
827 	/* Get irqs */
828 	irq = platform_get_irq(pdev, 0);
829 	if (irq < 0) {
830 		dev_err(&pdev->dev, "no irq for node %s\n", pdev->name);
831 		return -ENOENT;
832 	}
833 
834 	ret = devm_request_irq(&pdev->dev, irq, stm32_i2s_isr, IRQF_ONESHOT,
835 			       dev_name(&pdev->dev), i2s);
836 	if (ret) {
837 		dev_err(&pdev->dev, "irq request returned %d\n", ret);
838 		return ret;
839 	}
840 
841 	/* Reset */
842 	rst = devm_reset_control_get_exclusive(&pdev->dev, NULL);
843 	if (!IS_ERR(rst)) {
844 		reset_control_assert(rst);
845 		udelay(2);
846 		reset_control_deassert(rst);
847 	}
848 
849 	return 0;
850 }
851 
stm32_i2s_probe(struct platform_device * pdev)852 static int stm32_i2s_probe(struct platform_device *pdev)
853 {
854 	struct stm32_i2s_data *i2s;
855 	int ret;
856 
857 	i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
858 	if (!i2s)
859 		return -ENOMEM;
860 
861 	ret = stm32_i2s_parse_dt(pdev, i2s);
862 	if (ret)
863 		return ret;
864 
865 	i2s->pdev = pdev;
866 	i2s->ms_flg = I2S_MS_NOT_SET;
867 	spin_lock_init(&i2s->lock_fd);
868 	platform_set_drvdata(pdev, i2s);
869 
870 	ret = stm32_i2s_dais_init(pdev, i2s);
871 	if (ret)
872 		return ret;
873 
874 	i2s->regmap = devm_regmap_init_mmio(&pdev->dev, i2s->base,
875 					    i2s->regmap_conf);
876 	if (IS_ERR(i2s->regmap)) {
877 		dev_err(&pdev->dev, "regmap init failed\n");
878 		return PTR_ERR(i2s->regmap);
879 	}
880 
881 	ret = clk_prepare_enable(i2s->pclk);
882 	if (ret) {
883 		dev_err(&pdev->dev, "Enable pclk failed: %d\n", ret);
884 		return ret;
885 	}
886 
887 	ret = clk_prepare_enable(i2s->i2sclk);
888 	if (ret) {
889 		dev_err(&pdev->dev, "Enable i2sclk failed: %d\n", ret);
890 		goto err_pclk_disable;
891 	}
892 
893 	ret = devm_snd_soc_register_component(&pdev->dev, &stm32_i2s_component,
894 					      i2s->dai_drv, 1);
895 	if (ret)
896 		goto err_clocks_disable;
897 
898 	ret = devm_snd_dmaengine_pcm_register(&pdev->dev,
899 					      &stm32_i2s_pcm_config, 0);
900 	if (ret)
901 		goto err_clocks_disable;
902 
903 	/* Set SPI/I2S in i2s mode */
904 	ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
905 				 I2S_CGFR_I2SMOD, I2S_CGFR_I2SMOD);
906 	if (ret)
907 		goto err_clocks_disable;
908 
909 	return ret;
910 
911 err_clocks_disable:
912 	clk_disable_unprepare(i2s->i2sclk);
913 err_pclk_disable:
914 	clk_disable_unprepare(i2s->pclk);
915 
916 	return ret;
917 }
918 
stm32_i2s_remove(struct platform_device * pdev)919 static int stm32_i2s_remove(struct platform_device *pdev)
920 {
921 	struct stm32_i2s_data *i2s = platform_get_drvdata(pdev);
922 
923 	clk_disable_unprepare(i2s->i2sclk);
924 	clk_disable_unprepare(i2s->pclk);
925 
926 	return 0;
927 }
928 
929 MODULE_DEVICE_TABLE(of, stm32_i2s_ids);
930 
931 static struct platform_driver stm32_i2s_driver = {
932 	.driver = {
933 		.name = "st,stm32-i2s",
934 		.of_match_table = stm32_i2s_ids,
935 	},
936 	.probe = stm32_i2s_probe,
937 	.remove = stm32_i2s_remove,
938 };
939 
940 module_platform_driver(stm32_i2s_driver);
941 
942 MODULE_DESCRIPTION("STM32 Soc i2s Interface");
943 MODULE_AUTHOR("Olivier Moysan, <olivier.moysan@st.com>");
944 MODULE_ALIAS("platform:stm32-i2s");
945 MODULE_LICENSE("GPL v2");
946