xref: /linux/sound/soc/stm/stm32_i2s.c (revision 177bf8620cf4ed290ee170a6c5966adc0924b336)
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/clk-provider.h>
12 #include <linux/delay.h>
13 #include <linux/module.h>
14 #include <linux/of_irq.h>
15 #include <linux/of_platform.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/regmap.h>
18 #include <linux/reset.h>
19 #include <linux/spinlock.h>
20 
21 #include <sound/dmaengine_pcm.h>
22 #include <sound/pcm_params.h>
23 
24 #define STM32_I2S_CR1_REG	0x0
25 #define STM32_I2S_CFG1_REG	0x08
26 #define STM32_I2S_CFG2_REG	0x0C
27 #define STM32_I2S_IER_REG	0x10
28 #define STM32_I2S_SR_REG	0x14
29 #define STM32_I2S_IFCR_REG	0x18
30 #define STM32_I2S_TXDR_REG	0X20
31 #define STM32_I2S_RXDR_REG	0x30
32 #define STM32_I2S_CGFR_REG	0X50
33 #define STM32_I2S_HWCFGR_REG	0x3F0
34 #define STM32_I2S_VERR_REG	0x3F4
35 #define STM32_I2S_IPIDR_REG	0x3F8
36 #define STM32_I2S_SIDR_REG	0x3FC
37 
38 /* Bit definition for SPI2S_CR1 register */
39 #define I2S_CR1_SPE		BIT(0)
40 #define I2S_CR1_CSTART		BIT(9)
41 #define I2S_CR1_CSUSP		BIT(10)
42 #define I2S_CR1_HDDIR		BIT(11)
43 #define I2S_CR1_SSI		BIT(12)
44 #define I2S_CR1_CRC33_17	BIT(13)
45 #define I2S_CR1_RCRCI		BIT(14)
46 #define I2S_CR1_TCRCI		BIT(15)
47 
48 /* Bit definition for SPI_CFG2 register */
49 #define I2S_CFG2_IOSWP_SHIFT	15
50 #define I2S_CFG2_IOSWP		BIT(I2S_CFG2_IOSWP_SHIFT)
51 #define I2S_CFG2_LSBFRST	BIT(23)
52 #define I2S_CFG2_AFCNTR		BIT(31)
53 
54 /* Bit definition for SPI_CFG1 register */
55 #define I2S_CFG1_FTHVL_SHIFT	5
56 #define I2S_CFG1_FTHVL_MASK	GENMASK(8, I2S_CFG1_FTHVL_SHIFT)
57 #define I2S_CFG1_FTHVL_SET(x)	((x) << I2S_CFG1_FTHVL_SHIFT)
58 
59 #define I2S_CFG1_TXDMAEN	BIT(15)
60 #define I2S_CFG1_RXDMAEN	BIT(14)
61 
62 /* Bit definition for SPI2S_IER register */
63 #define I2S_IER_RXPIE		BIT(0)
64 #define I2S_IER_TXPIE		BIT(1)
65 #define I2S_IER_DPXPIE		BIT(2)
66 #define I2S_IER_EOTIE		BIT(3)
67 #define I2S_IER_TXTFIE		BIT(4)
68 #define I2S_IER_UDRIE		BIT(5)
69 #define I2S_IER_OVRIE		BIT(6)
70 #define I2S_IER_CRCEIE		BIT(7)
71 #define I2S_IER_TIFREIE		BIT(8)
72 #define I2S_IER_MODFIE		BIT(9)
73 #define I2S_IER_TSERFIE		BIT(10)
74 
75 /* Bit definition for SPI2S_SR register */
76 #define I2S_SR_RXP		BIT(0)
77 #define I2S_SR_TXP		BIT(1)
78 #define I2S_SR_DPXP		BIT(2)
79 #define I2S_SR_EOT		BIT(3)
80 #define I2S_SR_TXTF		BIT(4)
81 #define I2S_SR_UDR		BIT(5)
82 #define I2S_SR_OVR		BIT(6)
83 #define I2S_SR_CRCERR		BIT(7)
84 #define I2S_SR_TIFRE		BIT(8)
85 #define I2S_SR_MODF		BIT(9)
86 #define I2S_SR_TSERF		BIT(10)
87 #define I2S_SR_SUSP		BIT(11)
88 #define I2S_SR_TXC		BIT(12)
89 #define I2S_SR_RXPLVL		GENMASK(14, 13)
90 #define I2S_SR_RXWNE		BIT(15)
91 
92 #define I2S_SR_MASK		GENMASK(15, 0)
93 
94 /* Bit definition for SPI_IFCR register */
95 #define I2S_IFCR_EOTC		BIT(3)
96 #define I2S_IFCR_TXTFC		BIT(4)
97 #define I2S_IFCR_UDRC		BIT(5)
98 #define I2S_IFCR_OVRC		BIT(6)
99 #define I2S_IFCR_CRCEC		BIT(7)
100 #define I2S_IFCR_TIFREC		BIT(8)
101 #define I2S_IFCR_MODFC		BIT(9)
102 #define I2S_IFCR_TSERFC		BIT(10)
103 #define I2S_IFCR_SUSPC		BIT(11)
104 
105 #define I2S_IFCR_MASK		GENMASK(11, 3)
106 
107 /* Bit definition for SPI_I2SCGFR register */
108 #define I2S_CGFR_I2SMOD		BIT(0)
109 
110 #define I2S_CGFR_I2SCFG_SHIFT	1
111 #define I2S_CGFR_I2SCFG_MASK	GENMASK(3, I2S_CGFR_I2SCFG_SHIFT)
112 #define I2S_CGFR_I2SCFG_SET(x)	((x) << I2S_CGFR_I2SCFG_SHIFT)
113 
114 #define I2S_CGFR_I2SSTD_SHIFT	4
115 #define I2S_CGFR_I2SSTD_MASK	GENMASK(5, I2S_CGFR_I2SSTD_SHIFT)
116 #define I2S_CGFR_I2SSTD_SET(x)	((x) << I2S_CGFR_I2SSTD_SHIFT)
117 
118 #define I2S_CGFR_PCMSYNC	BIT(7)
119 
120 #define I2S_CGFR_DATLEN_SHIFT	8
121 #define I2S_CGFR_DATLEN_MASK	GENMASK(9, I2S_CGFR_DATLEN_SHIFT)
122 #define I2S_CGFR_DATLEN_SET(x)	((x) << I2S_CGFR_DATLEN_SHIFT)
123 
124 #define I2S_CGFR_CHLEN_SHIFT	10
125 #define I2S_CGFR_CHLEN		BIT(I2S_CGFR_CHLEN_SHIFT)
126 #define I2S_CGFR_CKPOL		BIT(11)
127 #define I2S_CGFR_FIXCH		BIT(12)
128 #define I2S_CGFR_WSINV		BIT(13)
129 #define I2S_CGFR_DATFMT		BIT(14)
130 
131 #define I2S_CGFR_I2SDIV_SHIFT	16
132 #define I2S_CGFR_I2SDIV_BIT_H	23
133 #define I2S_CGFR_I2SDIV_MASK	GENMASK(I2S_CGFR_I2SDIV_BIT_H,\
134 				I2S_CGFR_I2SDIV_SHIFT)
135 #define I2S_CGFR_I2SDIV_SET(x)	((x) << I2S_CGFR_I2SDIV_SHIFT)
136 #define	I2S_CGFR_I2SDIV_MAX	((1 << (I2S_CGFR_I2SDIV_BIT_H -\
137 				I2S_CGFR_I2SDIV_SHIFT)) - 1)
138 
139 #define I2S_CGFR_ODD_SHIFT	24
140 #define I2S_CGFR_ODD		BIT(I2S_CGFR_ODD_SHIFT)
141 #define I2S_CGFR_MCKOE		BIT(25)
142 
143 /* Registers below apply to I2S version 1.1 and more */
144 
145 /* Bit definition for SPI_HWCFGR register */
146 #define I2S_HWCFGR_I2S_SUPPORT_MASK	GENMASK(15, 12)
147 
148 /* Bit definition for SPI_VERR register */
149 #define I2S_VERR_MIN_MASK	GENMASK(3, 0)
150 #define I2S_VERR_MAJ_MASK	GENMASK(7, 4)
151 
152 /* Bit definition for SPI_IPIDR register */
153 #define I2S_IPIDR_ID_MASK	GENMASK(31, 0)
154 
155 /* Bit definition for SPI_SIDR register */
156 #define I2S_SIDR_ID_MASK	GENMASK(31, 0)
157 
158 #define I2S_IPIDR_NUMBER	0x00130022
159 
160 enum i2s_master_mode {
161 	I2S_MS_NOT_SET,
162 	I2S_MS_MASTER,
163 	I2S_MS_SLAVE,
164 };
165 
166 enum i2s_mode {
167 	I2S_I2SMOD_TX_SLAVE,
168 	I2S_I2SMOD_RX_SLAVE,
169 	I2S_I2SMOD_TX_MASTER,
170 	I2S_I2SMOD_RX_MASTER,
171 	I2S_I2SMOD_FD_SLAVE,
172 	I2S_I2SMOD_FD_MASTER,
173 };
174 
175 enum i2s_fifo_th {
176 	I2S_FIFO_TH_NONE,
177 	I2S_FIFO_TH_ONE_QUARTER,
178 	I2S_FIFO_TH_HALF,
179 	I2S_FIFO_TH_THREE_QUARTER,
180 	I2S_FIFO_TH_FULL,
181 };
182 
183 enum i2s_std {
184 	I2S_STD_I2S,
185 	I2S_STD_LEFT_J,
186 	I2S_STD_RIGHT_J,
187 	I2S_STD_DSP,
188 };
189 
190 enum i2s_datlen {
191 	I2S_I2SMOD_DATLEN_16,
192 	I2S_I2SMOD_DATLEN_24,
193 	I2S_I2SMOD_DATLEN_32,
194 };
195 
196 #define STM32_I2S_FIFO_SIZE		16
197 
198 #define STM32_I2S_IS_MASTER(x)		((x)->ms_flg == I2S_MS_MASTER)
199 #define STM32_I2S_IS_SLAVE(x)		((x)->ms_flg == I2S_MS_SLAVE)
200 
201 #define STM32_I2S_NAME_LEN		32
202 #define STM32_I2S_RATE_11K		11025
203 #define STM32_I2S_MAX_SAMPLE_RATE_8K	192000
204 #define STM32_I2S_MAX_SAMPLE_RATE_11K	176400
205 #define STM32_I2S_CLK_RATE_TOLERANCE	1000 /* ppm */
206 
207 /**
208  * struct stm32_i2s_data - private data of I2S
209  * @conf: I2S configuration pointer
210  * @regmap: I2S register map pointer
211  * @pdev: device data pointer
212  * @dai_drv: DAI driver pointer
213  * @dma_data_tx: dma configuration data for tx channel
214  * @dma_data_rx: dma configuration data for tx channel
215  * @substream: PCM substream data pointer
216  * @i2sclk: kernel clock feeding the I2S clock generator
217  * @i2smclk: master clock from I2S mclk provider
218  * @pclk: peripheral clock driving bus interface
219  * @x8kclk: I2S parent clock for sampling frequencies multiple of 8kHz
220  * @x11kclk: I2S parent clock for sampling frequencies multiple of 11kHz
221  * @base:  mmio register base virtual address
222  * @phys_addr: I2S registers physical base address
223  * @lock_fd: lock to manage race conditions in full duplex mode
224  * @irq_lock: prevent race condition with IRQ
225  * @mclk_rate: master clock frequency (Hz)
226  * @fmt: DAI protocol
227  * @divider: prescaler division ratio
228  * @div: prescaler div field
229  * @odd: prescaler odd field
230  * @i2s_clk_flg: flag set while exclusivity on I2S kernel clock is active
231  * @refcount: keep count of opened streams on I2S
232  * @ms_flg: master mode flag.
233  * @set_i2s_clk_rate: set I2S kernel clock rate
234  * @put_i2s_clk_rate: put I2S kernel clock rate
235  */
236 struct stm32_i2s_data {
237 	const struct stm32_i2s_conf *conf;
238 	struct regmap *regmap;
239 	struct platform_device *pdev;
240 	struct snd_soc_dai_driver *dai_drv;
241 	struct snd_dmaengine_dai_dma_data dma_data_tx;
242 	struct snd_dmaengine_dai_dma_data dma_data_rx;
243 	struct snd_pcm_substream *substream;
244 	struct clk *i2sclk;
245 	struct clk *i2smclk;
246 	struct clk *pclk;
247 	struct clk *x8kclk;
248 	struct clk *x11kclk;
249 	void __iomem *base;
250 	dma_addr_t phys_addr;
251 	spinlock_t lock_fd; /* Manage race conditions for full duplex */
252 	spinlock_t irq_lock; /* used to prevent race condition with IRQ */
253 	unsigned int mclk_rate;
254 	unsigned int fmt;
255 	unsigned int divider;
256 	unsigned int div;
257 	bool odd;
258 	bool i2s_clk_flg;
259 	int refcount;
260 	int ms_flg;
261 	int (*set_i2s_clk_rate)(struct stm32_i2s_data *i2s, unsigned int rate);
262 	void (*put_i2s_clk_rate)(struct stm32_i2s_data *i2s);
263 };
264 
265 /**
266  * struct stm32_i2s_conf - I2S configuration
267  * @regmap_conf: regmap configuration pointer
268  * @get_i2s_clk_parent: get parent clock of I2S kernel clock
269  */
270 struct stm32_i2s_conf {
271 	const struct regmap_config *regmap_conf;
272 	int (*get_i2s_clk_parent)(struct stm32_i2s_data *i2s);
273 };
274 
275 struct stm32_i2smclk_data {
276 	struct clk_hw hw;
277 	unsigned long freq;
278 	struct stm32_i2s_data *i2s_data;
279 };
280 
281 #define to_mclk_data(_hw) container_of(_hw, struct stm32_i2smclk_data, hw)
282 
283 static int stm32_i2s_get_parent_clk(struct stm32_i2s_data *i2s);
284 
stm32_i2s_calc_clk_div(struct stm32_i2s_data * i2s,unsigned long input_rate,unsigned long output_rate)285 static int stm32_i2s_calc_clk_div(struct stm32_i2s_data *i2s,
286 				  unsigned long input_rate,
287 				  unsigned long output_rate)
288 {
289 	unsigned int ratio, div, divider = 1;
290 	bool odd;
291 
292 	ratio = DIV_ROUND_CLOSEST(input_rate, output_rate);
293 
294 	/* Check the parity of the divider */
295 	odd = ratio & 0x1;
296 
297 	/* Compute the div prescaler */
298 	div = ratio >> 1;
299 
300 	/* If div is 0 actual divider is 1 */
301 	if (div) {
302 		divider = ((2 * div) + odd);
303 		dev_dbg(&i2s->pdev->dev, "Divider: 2*%d(div)+%d(odd) = %d\n",
304 			div, odd, divider);
305 	}
306 
307 	/* Division by three is not allowed by I2S prescaler */
308 	if ((div == 1 && odd) || div > I2S_CGFR_I2SDIV_MAX) {
309 		dev_err(&i2s->pdev->dev, "Wrong divider setting\n");
310 		return -EINVAL;
311 	}
312 
313 	if (input_rate % divider)
314 		dev_dbg(&i2s->pdev->dev,
315 			"Rate not accurate. requested (%ld), actual (%ld)\n",
316 			output_rate, input_rate / divider);
317 
318 	i2s->div = div;
319 	i2s->odd = odd;
320 	i2s->divider = divider;
321 
322 	return 0;
323 }
324 
stm32_i2s_set_clk_div(struct stm32_i2s_data * i2s)325 static int stm32_i2s_set_clk_div(struct stm32_i2s_data *i2s)
326 {
327 	u32 cgfr, cgfr_mask;
328 
329 	cgfr = I2S_CGFR_I2SDIV_SET(i2s->div) | (i2s->odd << I2S_CGFR_ODD_SHIFT);
330 	cgfr_mask = I2S_CGFR_I2SDIV_MASK | I2S_CGFR_ODD;
331 
332 	return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
333 				  cgfr_mask, cgfr);
334 }
335 
stm32_i2s_rate_accurate(struct stm32_i2s_data * i2s,unsigned int max_rate,unsigned int rate)336 static bool stm32_i2s_rate_accurate(struct stm32_i2s_data *i2s,
337 				    unsigned int max_rate, unsigned int rate)
338 {
339 	struct platform_device *pdev = i2s->pdev;
340 	u64 delta, dividend;
341 	int ratio;
342 
343 	if (!rate) {
344 		dev_err(&pdev->dev, "Unexpected null rate\n");
345 		return false;
346 	}
347 
348 	ratio = DIV_ROUND_CLOSEST(max_rate, rate);
349 	if (!ratio)
350 		return false;
351 
352 	dividend = mul_u32_u32(1000000, abs(max_rate - (ratio * rate)));
353 	delta = div_u64(dividend, max_rate);
354 
355 	if (delta <= STM32_I2S_CLK_RATE_TOLERANCE)
356 		return true;
357 
358 	dev_dbg(&pdev->dev, "Rate [%u] not accurate\n", rate);
359 
360 	return false;
361 }
362 
stm32_i2s_set_parent_clock(struct stm32_i2s_data * i2s,unsigned int rate)363 static int stm32_i2s_set_parent_clock(struct stm32_i2s_data *i2s,
364 				      unsigned int rate)
365 {
366 	struct platform_device *pdev = i2s->pdev;
367 	struct clk *parent_clk;
368 	int ret;
369 
370 	if (!(rate % STM32_I2S_RATE_11K))
371 		parent_clk = i2s->x11kclk;
372 	else
373 		parent_clk = i2s->x8kclk;
374 
375 	ret = clk_set_parent(i2s->i2sclk, parent_clk);
376 	if (ret)
377 		dev_err(&pdev->dev,
378 			"Error %d setting i2sclk parent clock\n", ret);
379 
380 	return ret;
381 }
382 
stm32_i2s_put_parent_rate(struct stm32_i2s_data * i2s)383 static void stm32_i2s_put_parent_rate(struct stm32_i2s_data *i2s)
384 {
385 	if (i2s->i2s_clk_flg) {
386 		i2s->i2s_clk_flg = false;
387 		clk_rate_exclusive_put(i2s->i2sclk);
388 	}
389 }
390 
stm32_i2s_set_parent_rate(struct stm32_i2s_data * i2s,unsigned int rate)391 static int stm32_i2s_set_parent_rate(struct stm32_i2s_data *i2s,
392 				     unsigned int rate)
393 {
394 	struct platform_device *pdev = i2s->pdev;
395 	unsigned int i2s_clk_rate, i2s_clk_max_rate, i2s_curr_rate, i2s_new_rate;
396 	int ret, div;
397 
398 	/*
399 	 * Set maximum expected kernel clock frequency
400 	 * - mclk on:
401 	 *   f_i2s_ck = MCKDIV * mclk-fs * fs
402 	 *   Here typical 256 ratio is assumed for mclk-fs
403 	 * - mclk off:
404 	 *   f_i2s_ck = MCKDIV * FRL * fs
405 	 *   Where FRL=[16,32], MCKDIV=[1..256]
406 	 *   f_i2s_ck = i2s_clk_max_rate * 32 / 256
407 	 */
408 	if (!(rate % STM32_I2S_RATE_11K))
409 		i2s_clk_max_rate = STM32_I2S_MAX_SAMPLE_RATE_11K * 256;
410 	else
411 		i2s_clk_max_rate = STM32_I2S_MAX_SAMPLE_RATE_8K * 256;
412 
413 	if (!i2s->i2smclk)
414 		i2s_clk_max_rate /= 8;
415 
416 	/* Request exclusivity, as the clock may be shared by I2S instances */
417 	clk_rate_exclusive_get(i2s->i2sclk);
418 	i2s->i2s_clk_flg = true;
419 
420 	/*
421 	 * Check current kernel clock rate. If it gives the expected accuracy
422 	 * return immediately.
423 	 */
424 	i2s_curr_rate = clk_get_rate(i2s->i2sclk);
425 	if (stm32_i2s_rate_accurate(i2s, i2s_clk_max_rate, i2s_curr_rate))
426 		return 0;
427 
428 	/*
429 	 * Otherwise try to set the maximum rate and check the new actual rate.
430 	 * If the new rate does not give the expected accuracy, try to set
431 	 * lower rates for the kernel clock.
432 	 */
433 	i2s_clk_rate = i2s_clk_max_rate;
434 	div = 1;
435 	do {
436 		/* Check new rate accuracy. Return if ok */
437 		i2s_new_rate = clk_round_rate(i2s->i2sclk, i2s_clk_rate);
438 		if (stm32_i2s_rate_accurate(i2s, i2s_clk_rate, i2s_new_rate)) {
439 			ret = clk_set_rate(i2s->i2sclk, i2s_clk_rate);
440 			if (ret) {
441 				dev_err(&pdev->dev, "Error %d setting i2s_clk_rate rate. %s",
442 					ret, ret == -EBUSY ?
443 					"Active stream rates may be in conflict\n" : "\n");
444 				goto err;
445 			}
446 
447 			return 0;
448 		}
449 
450 		/* Try a lower frequency */
451 		div++;
452 		i2s_clk_rate = i2s_clk_max_rate / div;
453 	} while (i2s_clk_rate > rate);
454 
455 	/* no accurate rate found */
456 	dev_err(&pdev->dev, "Failed to find an accurate rate");
457 
458 err:
459 	stm32_i2s_put_parent_rate(i2s);
460 
461 	return -EINVAL;
462 }
463 
stm32_i2smclk_determine_rate(struct clk_hw * hw,struct clk_rate_request * req)464 static int stm32_i2smclk_determine_rate(struct clk_hw *hw,
465 					struct clk_rate_request *req)
466 {
467 	struct stm32_i2smclk_data *mclk = to_mclk_data(hw);
468 	struct stm32_i2s_data *i2s = mclk->i2s_data;
469 	int ret;
470 
471 	ret = stm32_i2s_calc_clk_div(i2s, req->best_parent_rate, req->rate);
472 	if (ret) {
473 		req->rate = ret;
474 
475 		return 0;
476 	}
477 
478 	mclk->freq = req->best_parent_rate / i2s->divider;
479 
480 	req->rate = mclk->freq;
481 
482 	return 0;
483 }
484 
stm32_i2smclk_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)485 static unsigned long stm32_i2smclk_recalc_rate(struct clk_hw *hw,
486 					       unsigned long parent_rate)
487 {
488 	struct stm32_i2smclk_data *mclk = to_mclk_data(hw);
489 
490 	return mclk->freq;
491 }
492 
stm32_i2smclk_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)493 static int stm32_i2smclk_set_rate(struct clk_hw *hw, unsigned long rate,
494 				  unsigned long parent_rate)
495 {
496 	struct stm32_i2smclk_data *mclk = to_mclk_data(hw);
497 	struct stm32_i2s_data *i2s = mclk->i2s_data;
498 	int ret;
499 
500 	ret = stm32_i2s_calc_clk_div(i2s, parent_rate, rate);
501 	if (ret)
502 		return ret;
503 
504 	ret = stm32_i2s_set_clk_div(i2s);
505 	if (ret)
506 		return ret;
507 
508 	mclk->freq = rate;
509 
510 	return 0;
511 }
512 
stm32_i2smclk_enable(struct clk_hw * hw)513 static int stm32_i2smclk_enable(struct clk_hw *hw)
514 {
515 	struct stm32_i2smclk_data *mclk = to_mclk_data(hw);
516 	struct stm32_i2s_data *i2s = mclk->i2s_data;
517 
518 	dev_dbg(&i2s->pdev->dev, "Enable master clock\n");
519 
520 	return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
521 				    I2S_CGFR_MCKOE, I2S_CGFR_MCKOE);
522 }
523 
stm32_i2smclk_disable(struct clk_hw * hw)524 static void stm32_i2smclk_disable(struct clk_hw *hw)
525 {
526 	struct stm32_i2smclk_data *mclk = to_mclk_data(hw);
527 	struct stm32_i2s_data *i2s = mclk->i2s_data;
528 
529 	dev_dbg(&i2s->pdev->dev, "Disable master clock\n");
530 
531 	regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG, I2S_CGFR_MCKOE, 0);
532 }
533 
534 static const struct clk_ops mclk_ops = {
535 	.enable = stm32_i2smclk_enable,
536 	.disable = stm32_i2smclk_disable,
537 	.recalc_rate = stm32_i2smclk_recalc_rate,
538 	.determine_rate = stm32_i2smclk_determine_rate,
539 	.set_rate = stm32_i2smclk_set_rate,
540 };
541 
stm32_i2s_add_mclk_provider(struct stm32_i2s_data * i2s)542 static int stm32_i2s_add_mclk_provider(struct stm32_i2s_data *i2s)
543 {
544 	struct clk_hw *hw;
545 	struct stm32_i2smclk_data *mclk;
546 	struct device *dev = &i2s->pdev->dev;
547 	const char *pname = __clk_get_name(i2s->i2sclk);
548 	char *mclk_name, *p, *s = (char *)pname;
549 	int ret, i = 0;
550 
551 	mclk = devm_kzalloc(dev, sizeof(*mclk), GFP_KERNEL);
552 	if (!mclk)
553 		return -ENOMEM;
554 
555 	mclk_name = devm_kcalloc(dev, sizeof(char),
556 				 STM32_I2S_NAME_LEN, GFP_KERNEL);
557 	if (!mclk_name)
558 		return -ENOMEM;
559 
560 	/*
561 	 * Forge mclk clock name from parent clock name and suffix.
562 	 * String after "_" char is stripped in parent name.
563 	 */
564 	p = mclk_name;
565 	while (*s && *s != '_' && (i < (STM32_I2S_NAME_LEN - 7))) {
566 		*p++ = *s++;
567 		i++;
568 	}
569 	strcat(p, "_mclk");
570 
571 	mclk->hw.init = CLK_HW_INIT(mclk_name, pname, &mclk_ops, 0);
572 	mclk->i2s_data = i2s;
573 	hw = &mclk->hw;
574 
575 	dev_dbg(dev, "Register master clock %s\n", mclk_name);
576 	ret = devm_clk_hw_register(&i2s->pdev->dev, hw);
577 	if (ret) {
578 		dev_err(dev, "mclk register fails with error %d\n", ret);
579 		return ret;
580 	}
581 	i2s->i2smclk = hw->clk;
582 
583 	/* register mclk provider */
584 	return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get, hw);
585 }
586 
stm32_i2s_isr(int irq,void * devid)587 static irqreturn_t stm32_i2s_isr(int irq, void *devid)
588 {
589 	struct stm32_i2s_data *i2s = (struct stm32_i2s_data *)devid;
590 	struct platform_device *pdev = i2s->pdev;
591 	u32 sr, ier;
592 	unsigned long flags;
593 	int err = 0;
594 
595 	regmap_read(i2s->regmap, STM32_I2S_SR_REG, &sr);
596 	regmap_read(i2s->regmap, STM32_I2S_IER_REG, &ier);
597 
598 	flags = sr & ier;
599 	if (!flags) {
600 		dev_dbg(&pdev->dev, "Spurious IRQ sr=0x%08x, ier=0x%08x\n",
601 			sr, ier);
602 		return IRQ_NONE;
603 	}
604 
605 	regmap_write_bits(i2s->regmap, STM32_I2S_IFCR_REG,
606 			  I2S_IFCR_MASK, flags);
607 
608 	if (flags & I2S_SR_OVR) {
609 		dev_dbg(&pdev->dev, "Overrun\n");
610 		err = 1;
611 	}
612 
613 	if (flags & I2S_SR_UDR) {
614 		dev_dbg(&pdev->dev, "Underrun\n");
615 		err = 1;
616 	}
617 
618 	if (flags & I2S_SR_TIFRE)
619 		dev_dbg(&pdev->dev, "Frame error\n");
620 
621 	spin_lock(&i2s->irq_lock);
622 	if (err && i2s->substream)
623 		snd_pcm_stop_xrun(i2s->substream);
624 	spin_unlock(&i2s->irq_lock);
625 
626 	return IRQ_HANDLED;
627 }
628 
stm32_i2s_readable_reg(struct device * dev,unsigned int reg)629 static bool stm32_i2s_readable_reg(struct device *dev, unsigned int reg)
630 {
631 	switch (reg) {
632 	case STM32_I2S_CR1_REG:
633 	case STM32_I2S_CFG1_REG:
634 	case STM32_I2S_CFG2_REG:
635 	case STM32_I2S_IER_REG:
636 	case STM32_I2S_SR_REG:
637 	case STM32_I2S_RXDR_REG:
638 	case STM32_I2S_CGFR_REG:
639 	case STM32_I2S_HWCFGR_REG:
640 	case STM32_I2S_VERR_REG:
641 	case STM32_I2S_IPIDR_REG:
642 	case STM32_I2S_SIDR_REG:
643 		return true;
644 	default:
645 		return false;
646 	}
647 }
648 
stm32_i2s_volatile_reg(struct device * dev,unsigned int reg)649 static bool stm32_i2s_volatile_reg(struct device *dev, unsigned int reg)
650 {
651 	switch (reg) {
652 	case STM32_I2S_SR_REG:
653 	case STM32_I2S_RXDR_REG:
654 		return true;
655 	default:
656 		return false;
657 	}
658 }
659 
stm32_i2s_writeable_reg(struct device * dev,unsigned int reg)660 static bool stm32_i2s_writeable_reg(struct device *dev, unsigned int reg)
661 {
662 	switch (reg) {
663 	case STM32_I2S_CR1_REG:
664 	case STM32_I2S_CFG1_REG:
665 	case STM32_I2S_CFG2_REG:
666 	case STM32_I2S_IER_REG:
667 	case STM32_I2S_IFCR_REG:
668 	case STM32_I2S_TXDR_REG:
669 	case STM32_I2S_CGFR_REG:
670 		return true;
671 	default:
672 		return false;
673 	}
674 }
675 
stm32_i2s_set_dai_fmt(struct snd_soc_dai * cpu_dai,unsigned int fmt)676 static int stm32_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
677 {
678 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
679 	u32 cgfr;
680 	u32 cgfr_mask =  I2S_CGFR_I2SSTD_MASK | I2S_CGFR_CKPOL |
681 			 I2S_CGFR_WSINV | I2S_CGFR_I2SCFG_MASK;
682 
683 	dev_dbg(cpu_dai->dev, "fmt %x\n", fmt);
684 
685 	/*
686 	 * winv = 0 : default behavior (high/low) for all standards
687 	 * ckpol = 0 for all standards.
688 	 */
689 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
690 	case SND_SOC_DAIFMT_I2S:
691 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_I2S);
692 		break;
693 	case SND_SOC_DAIFMT_MSB:
694 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_LEFT_J);
695 		break;
696 	case SND_SOC_DAIFMT_LSB:
697 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_RIGHT_J);
698 		break;
699 	case SND_SOC_DAIFMT_DSP_A:
700 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_DSP);
701 		break;
702 	/* DSP_B not mapped on I2S PCM long format. 1 bit offset does not fit */
703 	default:
704 		dev_err(cpu_dai->dev, "Unsupported protocol %#x\n",
705 			fmt & SND_SOC_DAIFMT_FORMAT_MASK);
706 		return -EINVAL;
707 	}
708 
709 	/* DAI clock strobing */
710 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
711 	case SND_SOC_DAIFMT_NB_NF:
712 		break;
713 	case SND_SOC_DAIFMT_IB_NF:
714 		cgfr |= I2S_CGFR_CKPOL;
715 		break;
716 	case SND_SOC_DAIFMT_NB_IF:
717 		cgfr |= I2S_CGFR_WSINV;
718 		break;
719 	case SND_SOC_DAIFMT_IB_IF:
720 		cgfr |= I2S_CGFR_CKPOL;
721 		cgfr |= I2S_CGFR_WSINV;
722 		break;
723 	default:
724 		dev_err(cpu_dai->dev, "Unsupported strobing %#x\n",
725 			fmt & SND_SOC_DAIFMT_INV_MASK);
726 		return -EINVAL;
727 	}
728 
729 	/* DAI clock master masks */
730 	switch (fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) {
731 	case SND_SOC_DAIFMT_BC_FC:
732 		i2s->ms_flg = I2S_MS_SLAVE;
733 		break;
734 	case SND_SOC_DAIFMT_BP_FP:
735 		i2s->ms_flg = I2S_MS_MASTER;
736 		break;
737 	default:
738 		dev_err(cpu_dai->dev, "Unsupported mode %#x\n",
739 			fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK);
740 		return -EINVAL;
741 	}
742 
743 	i2s->fmt = fmt;
744 	return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
745 				  cgfr_mask, cgfr);
746 }
747 
stm32_i2s_set_sysclk(struct snd_soc_dai * cpu_dai,int clk_id,unsigned int freq,int dir)748 static int stm32_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
749 				int clk_id, unsigned int freq, int dir)
750 {
751 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
752 	int ret = 0;
753 
754 	dev_dbg(cpu_dai->dev, "I2S MCLK frequency is %uHz. mode: %s, dir: %s\n",
755 		freq, STM32_I2S_IS_MASTER(i2s) ? "master" : "slave",
756 		dir ? "output" : "input");
757 
758 	/* MCLK generation is available only in master mode */
759 	if (dir == SND_SOC_CLOCK_OUT && STM32_I2S_IS_MASTER(i2s)) {
760 		if (!i2s->i2smclk) {
761 			dev_dbg(cpu_dai->dev, "No MCLK registered\n");
762 			return 0;
763 		}
764 
765 		/* Assume shutdown if requested frequency is 0Hz */
766 		if (!freq) {
767 			/* Release mclk rate only if rate was actually set */
768 			if (i2s->mclk_rate) {
769 				clk_rate_exclusive_put(i2s->i2smclk);
770 				i2s->mclk_rate = 0;
771 			}
772 
773 			if (i2s->put_i2s_clk_rate)
774 				i2s->put_i2s_clk_rate(i2s);
775 
776 			return regmap_update_bits(i2s->regmap,
777 						  STM32_I2S_CGFR_REG,
778 						  I2S_CGFR_MCKOE, 0);
779 		}
780 		/* If master clock is used, set parent clock now */
781 		ret = i2s->set_i2s_clk_rate(i2s, freq);
782 		if (ret)
783 			return ret;
784 		ret = clk_set_rate_exclusive(i2s->i2smclk, freq);
785 		if (ret) {
786 			dev_err(cpu_dai->dev, "Could not set mclk rate\n");
787 			return ret;
788 		}
789 		ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
790 					 I2S_CGFR_MCKOE, I2S_CGFR_MCKOE);
791 		if (!ret)
792 			i2s->mclk_rate = freq;
793 	}
794 
795 	return ret;
796 }
797 
stm32_i2s_configure_clock(struct snd_soc_dai * cpu_dai,struct snd_pcm_hw_params * params)798 static int stm32_i2s_configure_clock(struct snd_soc_dai *cpu_dai,
799 				     struct snd_pcm_hw_params *params)
800 {
801 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
802 	unsigned long i2s_clock_rate;
803 	unsigned int nb_bits, frame_len;
804 	unsigned int rate = params_rate(params);
805 	u32 cgfr;
806 	int ret;
807 
808 	if (!i2s->mclk_rate) {
809 		ret = i2s->set_i2s_clk_rate(i2s, rate);
810 		if (ret)
811 			return ret;
812 	}
813 	i2s_clock_rate = clk_get_rate(i2s->i2sclk);
814 
815 	/*
816 	 * mckl = mclk_ratio x ws
817 	 *   i2s mode : mclk_ratio = 256
818 	 *   dsp mode : mclk_ratio = 128
819 	 *
820 	 * mclk on
821 	 *   i2s mode : div = i2s_clk / (mclk_ratio * ws)
822 	 *   dsp mode : div = i2s_clk / (mclk_ratio * ws)
823 	 * mclk off
824 	 *   i2s mode : div = i2s_clk / (nb_bits x ws)
825 	 *   dsp mode : div = i2s_clk / (nb_bits x ws)
826 	 */
827 	if (i2s->mclk_rate) {
828 		ret = stm32_i2s_calc_clk_div(i2s, i2s_clock_rate,
829 					     i2s->mclk_rate);
830 		if (ret)
831 			return ret;
832 	} else {
833 		frame_len = 32;
834 		if ((i2s->fmt & SND_SOC_DAIFMT_FORMAT_MASK) ==
835 		    SND_SOC_DAIFMT_DSP_A)
836 			frame_len = 16;
837 
838 		/* master clock not enabled */
839 		ret = regmap_read(i2s->regmap, STM32_I2S_CGFR_REG, &cgfr);
840 		if (ret < 0)
841 			return ret;
842 
843 		nb_bits = frame_len * (FIELD_GET(I2S_CGFR_CHLEN, cgfr) + 1);
844 		ret = stm32_i2s_calc_clk_div(i2s, i2s_clock_rate,
845 					     (nb_bits * rate));
846 		if (ret)
847 			return ret;
848 	}
849 
850 	ret = stm32_i2s_set_clk_div(i2s);
851 	if (ret < 0)
852 		return ret;
853 
854 	/* Set bitclock and frameclock to their inactive state */
855 	return regmap_update_bits(i2s->regmap, STM32_I2S_CFG2_REG,
856 				  I2S_CFG2_AFCNTR, I2S_CFG2_AFCNTR);
857 }
858 
stm32_i2s_configure(struct snd_soc_dai * cpu_dai,struct snd_pcm_hw_params * params,struct snd_pcm_substream * substream)859 static int stm32_i2s_configure(struct snd_soc_dai *cpu_dai,
860 			       struct snd_pcm_hw_params *params,
861 			       struct snd_pcm_substream *substream)
862 {
863 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
864 	int format = params_width(params);
865 	u32 cfgr, cfgr_mask, cfg1;
866 	unsigned int fthlv;
867 	int ret;
868 
869 	switch (format) {
870 	case 16:
871 		cfgr = I2S_CGFR_DATLEN_SET(I2S_I2SMOD_DATLEN_16);
872 		cfgr_mask = I2S_CGFR_DATLEN_MASK | I2S_CGFR_CHLEN;
873 		break;
874 	case 32:
875 		cfgr = I2S_CGFR_DATLEN_SET(I2S_I2SMOD_DATLEN_32) |
876 					   I2S_CGFR_CHLEN;
877 		cfgr_mask = I2S_CGFR_DATLEN_MASK | I2S_CGFR_CHLEN;
878 		break;
879 	default:
880 		dev_err(cpu_dai->dev, "Unexpected format %d", format);
881 		return -EINVAL;
882 	}
883 
884 	if (STM32_I2S_IS_SLAVE(i2s)) {
885 		cfgr |= I2S_CGFR_I2SCFG_SET(I2S_I2SMOD_FD_SLAVE);
886 
887 		/* As data length is either 16 or 32 bits, fixch always set */
888 		cfgr |= I2S_CGFR_FIXCH;
889 		cfgr_mask |= I2S_CGFR_FIXCH;
890 	} else {
891 		cfgr |= I2S_CGFR_I2SCFG_SET(I2S_I2SMOD_FD_MASTER);
892 	}
893 	cfgr_mask |= I2S_CGFR_I2SCFG_MASK;
894 
895 	ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
896 				 cfgr_mask, cfgr);
897 	if (ret < 0)
898 		return ret;
899 
900 	fthlv = STM32_I2S_FIFO_SIZE * I2S_FIFO_TH_ONE_QUARTER / 4;
901 	cfg1 = I2S_CFG1_FTHVL_SET(fthlv - 1);
902 
903 	return regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
904 				  I2S_CFG1_FTHVL_MASK, cfg1);
905 }
906 
stm32_i2s_startup(struct snd_pcm_substream * substream,struct snd_soc_dai * cpu_dai)907 static int stm32_i2s_startup(struct snd_pcm_substream *substream,
908 			     struct snd_soc_dai *cpu_dai)
909 {
910 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
911 	unsigned long flags;
912 	int ret;
913 
914 	spin_lock_irqsave(&i2s->irq_lock, flags);
915 	i2s->substream = substream;
916 	spin_unlock_irqrestore(&i2s->irq_lock, flags);
917 
918 	if ((i2s->fmt & SND_SOC_DAIFMT_FORMAT_MASK) != SND_SOC_DAIFMT_DSP_A)
919 		snd_pcm_hw_constraint_single(substream->runtime,
920 					     SNDRV_PCM_HW_PARAM_CHANNELS, 2);
921 
922 	ret = clk_prepare_enable(i2s->i2sclk);
923 	if (ret < 0) {
924 		dev_err(cpu_dai->dev, "Failed to enable clock: %d\n", ret);
925 		return ret;
926 	}
927 
928 	return regmap_write_bits(i2s->regmap, STM32_I2S_IFCR_REG,
929 				 I2S_IFCR_MASK, I2S_IFCR_MASK);
930 }
931 
stm32_i2s_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params,struct snd_soc_dai * cpu_dai)932 static int stm32_i2s_hw_params(struct snd_pcm_substream *substream,
933 			       struct snd_pcm_hw_params *params,
934 			       struct snd_soc_dai *cpu_dai)
935 {
936 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
937 	int ret;
938 
939 	ret = stm32_i2s_configure(cpu_dai, params, substream);
940 	if (ret < 0) {
941 		dev_err(cpu_dai->dev, "Configuration returned error %d\n", ret);
942 		return ret;
943 	}
944 
945 	if (STM32_I2S_IS_MASTER(i2s))
946 		ret = stm32_i2s_configure_clock(cpu_dai, params);
947 
948 	return ret;
949 }
950 
stm32_i2s_trigger(struct snd_pcm_substream * substream,int cmd,struct snd_soc_dai * cpu_dai)951 static int stm32_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
952 			     struct snd_soc_dai *cpu_dai)
953 {
954 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
955 	bool playback_flg = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK);
956 	u32 cfg1_mask, ier;
957 	int ret;
958 
959 	switch (cmd) {
960 	case SNDRV_PCM_TRIGGER_START:
961 	case SNDRV_PCM_TRIGGER_RESUME:
962 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
963 		/* Enable i2s */
964 		dev_dbg(cpu_dai->dev, "start I2S %s\n",
965 			snd_pcm_direction_name(substream->stream));
966 
967 		cfg1_mask = I2S_CFG1_RXDMAEN | I2S_CFG1_TXDMAEN;
968 		regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
969 				   cfg1_mask, cfg1_mask);
970 
971 		ret = regmap_update_bits(i2s->regmap, STM32_I2S_CR1_REG,
972 					 I2S_CR1_SPE, I2S_CR1_SPE);
973 		if (ret < 0) {
974 			dev_err(cpu_dai->dev, "Error %d enabling I2S\n", ret);
975 			return ret;
976 		}
977 
978 		ret = regmap_write_bits(i2s->regmap, STM32_I2S_CR1_REG,
979 					I2S_CR1_CSTART, I2S_CR1_CSTART);
980 		if (ret < 0) {
981 			dev_err(cpu_dai->dev, "Error %d starting I2S\n", ret);
982 			return ret;
983 		}
984 
985 		regmap_write_bits(i2s->regmap, STM32_I2S_IFCR_REG,
986 				  I2S_IFCR_MASK, I2S_IFCR_MASK);
987 
988 		spin_lock(&i2s->lock_fd);
989 		i2s->refcount++;
990 		if (playback_flg) {
991 			ier = I2S_IER_UDRIE;
992 		} else {
993 			ier = I2S_IER_OVRIE;
994 
995 			if (STM32_I2S_IS_MASTER(i2s) && i2s->refcount == 1)
996 				/* dummy write to gate bus clocks */
997 				regmap_write(i2s->regmap,
998 					     STM32_I2S_TXDR_REG, 0);
999 		}
1000 		spin_unlock(&i2s->lock_fd);
1001 
1002 		if (STM32_I2S_IS_SLAVE(i2s))
1003 			ier |= I2S_IER_TIFREIE;
1004 
1005 		regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG, ier, ier);
1006 		break;
1007 	case SNDRV_PCM_TRIGGER_STOP:
1008 	case SNDRV_PCM_TRIGGER_SUSPEND:
1009 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1010 		dev_dbg(cpu_dai->dev, "stop I2S %s\n",
1011 			snd_pcm_direction_name(substream->stream));
1012 
1013 		if (playback_flg)
1014 			regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG,
1015 					   I2S_IER_UDRIE,
1016 					   (unsigned int)~I2S_IER_UDRIE);
1017 		else
1018 			regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG,
1019 					   I2S_IER_OVRIE,
1020 					   (unsigned int)~I2S_IER_OVRIE);
1021 
1022 		spin_lock(&i2s->lock_fd);
1023 		i2s->refcount--;
1024 		if (i2s->refcount) {
1025 			spin_unlock(&i2s->lock_fd);
1026 			break;
1027 		}
1028 
1029 		ret = regmap_update_bits(i2s->regmap, STM32_I2S_CR1_REG,
1030 					 I2S_CR1_SPE, 0);
1031 		if (ret < 0) {
1032 			dev_err(cpu_dai->dev, "Error %d disabling I2S\n", ret);
1033 			spin_unlock(&i2s->lock_fd);
1034 			return ret;
1035 		}
1036 		spin_unlock(&i2s->lock_fd);
1037 
1038 		cfg1_mask = I2S_CFG1_RXDMAEN | I2S_CFG1_TXDMAEN;
1039 		regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
1040 				   cfg1_mask, 0);
1041 		break;
1042 	default:
1043 		return -EINVAL;
1044 	}
1045 
1046 	return 0;
1047 }
1048 
stm32_i2s_shutdown(struct snd_pcm_substream * substream,struct snd_soc_dai * cpu_dai)1049 static void stm32_i2s_shutdown(struct snd_pcm_substream *substream,
1050 			       struct snd_soc_dai *cpu_dai)
1051 {
1052 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
1053 	unsigned long flags;
1054 
1055 	clk_disable_unprepare(i2s->i2sclk);
1056 
1057 	/*
1058 	 * Release kernel clock if following conditions are fulfilled
1059 	 * - Master clock is not used. Kernel clock won't be released trough sysclk
1060 	 * - Put handler is defined. Involve that clock is managed exclusively
1061 	 */
1062 	if (!i2s->i2smclk && i2s->put_i2s_clk_rate)
1063 		i2s->put_i2s_clk_rate(i2s);
1064 
1065 	spin_lock_irqsave(&i2s->irq_lock, flags);
1066 	i2s->substream = NULL;
1067 	spin_unlock_irqrestore(&i2s->irq_lock, flags);
1068 }
1069 
stm32_i2s_dai_probe(struct snd_soc_dai * cpu_dai)1070 static int stm32_i2s_dai_probe(struct snd_soc_dai *cpu_dai)
1071 {
1072 	struct stm32_i2s_data *i2s = dev_get_drvdata(cpu_dai->dev);
1073 	struct snd_dmaengine_dai_dma_data *dma_data_tx = &i2s->dma_data_tx;
1074 	struct snd_dmaengine_dai_dma_data *dma_data_rx = &i2s->dma_data_rx;
1075 
1076 	/* Buswidth will be set by framework */
1077 	dma_data_tx->addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
1078 	dma_data_tx->addr = (dma_addr_t)(i2s->phys_addr) + STM32_I2S_TXDR_REG;
1079 	dma_data_tx->maxburst = 1;
1080 	dma_data_rx->addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
1081 	dma_data_rx->addr = (dma_addr_t)(i2s->phys_addr) + STM32_I2S_RXDR_REG;
1082 	dma_data_rx->maxburst = 1;
1083 
1084 	snd_soc_dai_init_dma_data(cpu_dai, dma_data_tx, dma_data_rx);
1085 
1086 	return 0;
1087 }
1088 
1089 static const struct regmap_config stm32_h7_i2s_regmap_conf = {
1090 	.reg_bits = 32,
1091 	.reg_stride = 4,
1092 	.val_bits = 32,
1093 	.max_register = STM32_I2S_SIDR_REG,
1094 	.readable_reg = stm32_i2s_readable_reg,
1095 	.volatile_reg = stm32_i2s_volatile_reg,
1096 	.writeable_reg = stm32_i2s_writeable_reg,
1097 	.num_reg_defaults_raw = STM32_I2S_SIDR_REG / sizeof(u32) + 1,
1098 	.fast_io = true,
1099 	.cache_type = REGCACHE_FLAT,
1100 };
1101 
1102 static const struct snd_soc_dai_ops stm32_i2s_pcm_dai_ops = {
1103 	.probe		= stm32_i2s_dai_probe,
1104 	.set_sysclk	= stm32_i2s_set_sysclk,
1105 	.set_fmt	= stm32_i2s_set_dai_fmt,
1106 	.startup	= stm32_i2s_startup,
1107 	.hw_params	= stm32_i2s_hw_params,
1108 	.trigger	= stm32_i2s_trigger,
1109 	.shutdown	= stm32_i2s_shutdown,
1110 };
1111 
1112 static const struct snd_pcm_hardware stm32_i2s_pcm_hw = {
1113 	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_MMAP,
1114 	.buffer_bytes_max = 8 * PAGE_SIZE,
1115 	.period_bytes_min = 1024,
1116 	.period_bytes_max = 4 * PAGE_SIZE,
1117 	.periods_min = 2,
1118 	.periods_max = 8,
1119 };
1120 
1121 static const struct snd_dmaengine_pcm_config stm32_i2s_pcm_config = {
1122 	.pcm_hardware	= &stm32_i2s_pcm_hw,
1123 	.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
1124 	.prealloc_buffer_size = PAGE_SIZE * 8,
1125 };
1126 
1127 static const struct snd_soc_component_driver stm32_i2s_component = {
1128 	.name = "stm32-i2s",
1129 	.legacy_dai_naming = 1,
1130 };
1131 
stm32_i2s_dai_init(struct snd_soc_pcm_stream * stream,char * stream_name)1132 static void stm32_i2s_dai_init(struct snd_soc_pcm_stream *stream,
1133 			       char *stream_name)
1134 {
1135 	stream->stream_name = stream_name;
1136 	stream->channels_min = 1;
1137 	stream->channels_max = 2;
1138 	stream->rates = SNDRV_PCM_RATE_8000_192000;
1139 	stream->formats = SNDRV_PCM_FMTBIT_S16_LE |
1140 				   SNDRV_PCM_FMTBIT_S32_LE;
1141 }
1142 
stm32_i2s_dais_init(struct platform_device * pdev,struct stm32_i2s_data * i2s)1143 static int stm32_i2s_dais_init(struct platform_device *pdev,
1144 			       struct stm32_i2s_data *i2s)
1145 {
1146 	struct snd_soc_dai_driver *dai_ptr;
1147 
1148 	dai_ptr = devm_kzalloc(&pdev->dev, sizeof(struct snd_soc_dai_driver),
1149 			       GFP_KERNEL);
1150 	if (!dai_ptr)
1151 		return -ENOMEM;
1152 
1153 	dai_ptr->ops = &stm32_i2s_pcm_dai_ops;
1154 	dai_ptr->id = 1;
1155 	stm32_i2s_dai_init(&dai_ptr->playback, "playback");
1156 	stm32_i2s_dai_init(&dai_ptr->capture, "capture");
1157 	i2s->dai_drv = dai_ptr;
1158 
1159 	return 0;
1160 }
1161 
1162 static const struct stm32_i2s_conf stm32_i2s_conf_h7 = {
1163 	.regmap_conf = &stm32_h7_i2s_regmap_conf,
1164 	.get_i2s_clk_parent = stm32_i2s_get_parent_clk,
1165 };
1166 
1167 static const struct stm32_i2s_conf stm32_i2s_conf_mp25 = {
1168 	.regmap_conf = &stm32_h7_i2s_regmap_conf
1169 };
1170 
1171 static const struct of_device_id stm32_i2s_ids[] = {
1172 	{ .compatible = "st,stm32h7-i2s", .data = &stm32_i2s_conf_h7 },
1173 	{ .compatible = "st,stm32mp25-i2s", .data = &stm32_i2s_conf_mp25 },
1174 	{},
1175 };
1176 
stm32_i2s_get_parent_clk(struct stm32_i2s_data * i2s)1177 static int stm32_i2s_get_parent_clk(struct stm32_i2s_data *i2s)
1178 {
1179 	struct device *dev = &i2s->pdev->dev;
1180 
1181 	i2s->x8kclk = devm_clk_get(dev, "x8k");
1182 	if (IS_ERR(i2s->x8kclk))
1183 		return dev_err_probe(dev, PTR_ERR(i2s->x8kclk), "Cannot get x8k parent clock\n");
1184 
1185 	i2s->x11kclk = devm_clk_get(dev, "x11k");
1186 	if (IS_ERR(i2s->x11kclk))
1187 		return dev_err_probe(dev, PTR_ERR(i2s->x11kclk), "Cannot get x11k parent clock\n");
1188 
1189 	return 0;
1190 }
1191 
stm32_i2s_parse_dt(struct platform_device * pdev,struct stm32_i2s_data * i2s)1192 static int stm32_i2s_parse_dt(struct platform_device *pdev,
1193 			      struct stm32_i2s_data *i2s)
1194 {
1195 	struct device_node *np = pdev->dev.of_node;
1196 	struct reset_control *rst;
1197 	struct resource *res;
1198 	int irq, ret;
1199 
1200 	if (!np)
1201 		return -ENODEV;
1202 
1203 	i2s->conf = device_get_match_data(&pdev->dev);
1204 	if (!i2s->conf)
1205 		return -EINVAL;
1206 
1207 	i2s->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1208 	if (IS_ERR(i2s->base))
1209 		return PTR_ERR(i2s->base);
1210 
1211 	i2s->phys_addr = res->start;
1212 
1213 	/* Get clocks */
1214 	i2s->pclk = devm_clk_get(&pdev->dev, "pclk");
1215 	if (IS_ERR(i2s->pclk))
1216 		return dev_err_probe(&pdev->dev, PTR_ERR(i2s->pclk),
1217 				     "Could not get pclk\n");
1218 
1219 	i2s->i2sclk = devm_clk_get(&pdev->dev, "i2sclk");
1220 	if (IS_ERR(i2s->i2sclk))
1221 		return dev_err_probe(&pdev->dev, PTR_ERR(i2s->i2sclk),
1222 				     "Could not get i2sclk\n");
1223 
1224 	if (i2s->conf->get_i2s_clk_parent) {
1225 		i2s->set_i2s_clk_rate = stm32_i2s_set_parent_clock;
1226 	} else {
1227 		i2s->set_i2s_clk_rate = stm32_i2s_set_parent_rate;
1228 		i2s->put_i2s_clk_rate = stm32_i2s_put_parent_rate;
1229 	}
1230 
1231 	if (i2s->conf->get_i2s_clk_parent) {
1232 		ret = i2s->conf->get_i2s_clk_parent(i2s);
1233 		if (ret)
1234 			return ret;
1235 	}
1236 
1237 	/* Register mclk provider if requested */
1238 	if (of_property_present(np, "#clock-cells")) {
1239 		ret = stm32_i2s_add_mclk_provider(i2s);
1240 		if (ret < 0)
1241 			return ret;
1242 	}
1243 
1244 	/* Get irqs */
1245 	irq = platform_get_irq(pdev, 0);
1246 	if (irq < 0)
1247 		return irq;
1248 
1249 	ret = devm_request_irq(&pdev->dev, irq, stm32_i2s_isr, 0,
1250 			       dev_name(&pdev->dev), i2s);
1251 	if (ret) {
1252 		dev_err(&pdev->dev, "irq request returned %d\n", ret);
1253 		return ret;
1254 	}
1255 
1256 	/* Reset */
1257 	rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
1258 	if (IS_ERR(rst))
1259 		return dev_err_probe(&pdev->dev, PTR_ERR(rst),
1260 				     "Reset controller error\n");
1261 
1262 	reset_control_assert(rst);
1263 	udelay(2);
1264 	reset_control_deassert(rst);
1265 
1266 	return 0;
1267 }
1268 
stm32_i2s_remove(struct platform_device * pdev)1269 static void stm32_i2s_remove(struct platform_device *pdev)
1270 {
1271 	snd_dmaengine_pcm_unregister(&pdev->dev);
1272 	snd_soc_unregister_component(&pdev->dev);
1273 	pm_runtime_disable(&pdev->dev);
1274 }
1275 
stm32_i2s_probe(struct platform_device * pdev)1276 static int stm32_i2s_probe(struct platform_device *pdev)
1277 {
1278 	struct stm32_i2s_data *i2s;
1279 	u32 val;
1280 	int ret;
1281 
1282 	i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
1283 	if (!i2s)
1284 		return -ENOMEM;
1285 
1286 	i2s->pdev = pdev;
1287 	i2s->ms_flg = I2S_MS_NOT_SET;
1288 	spin_lock_init(&i2s->lock_fd);
1289 	spin_lock_init(&i2s->irq_lock);
1290 	platform_set_drvdata(pdev, i2s);
1291 
1292 	ret = stm32_i2s_parse_dt(pdev, i2s);
1293 	if (ret)
1294 		return ret;
1295 
1296 	ret = stm32_i2s_dais_init(pdev, i2s);
1297 	if (ret)
1298 		return ret;
1299 
1300 	i2s->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "pclk",
1301 						i2s->base, i2s->conf->regmap_conf);
1302 	if (IS_ERR(i2s->regmap))
1303 		return dev_err_probe(&pdev->dev, PTR_ERR(i2s->regmap),
1304 				     "Regmap init error\n");
1305 
1306 	ret = snd_dmaengine_pcm_register(&pdev->dev, &stm32_i2s_pcm_config, 0);
1307 	if (ret)
1308 		return dev_err_probe(&pdev->dev, ret, "PCM DMA register error\n");
1309 
1310 	ret = snd_soc_register_component(&pdev->dev, &stm32_i2s_component,
1311 					 i2s->dai_drv, 1);
1312 	if (ret) {
1313 		snd_dmaengine_pcm_unregister(&pdev->dev);
1314 		return ret;
1315 	}
1316 
1317 	/* Set SPI/I2S in i2s mode */
1318 	ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
1319 				 I2S_CGFR_I2SMOD, I2S_CGFR_I2SMOD);
1320 	if (ret)
1321 		goto error;
1322 
1323 	ret = regmap_read(i2s->regmap, STM32_I2S_IPIDR_REG, &val);
1324 	if (ret)
1325 		goto error;
1326 
1327 	if (val == I2S_IPIDR_NUMBER) {
1328 		ret = regmap_read(i2s->regmap, STM32_I2S_HWCFGR_REG, &val);
1329 		if (ret)
1330 			goto error;
1331 
1332 		if (!FIELD_GET(I2S_HWCFGR_I2S_SUPPORT_MASK, val)) {
1333 			dev_err(&pdev->dev,
1334 				"Device does not support i2s mode\n");
1335 			ret = -EPERM;
1336 			goto error;
1337 		}
1338 
1339 		ret = regmap_read(i2s->regmap, STM32_I2S_VERR_REG, &val);
1340 		if (ret)
1341 			goto error;
1342 
1343 		dev_dbg(&pdev->dev, "I2S version: %lu.%lu registered\n",
1344 			FIELD_GET(I2S_VERR_MAJ_MASK, val),
1345 			FIELD_GET(I2S_VERR_MIN_MASK, val));
1346 	}
1347 
1348 	pm_runtime_enable(&pdev->dev);
1349 
1350 	return ret;
1351 
1352 error:
1353 	stm32_i2s_remove(pdev);
1354 
1355 	return ret;
1356 }
1357 
1358 MODULE_DEVICE_TABLE(of, stm32_i2s_ids);
1359 
stm32_i2s_suspend(struct device * dev)1360 static int stm32_i2s_suspend(struct device *dev)
1361 {
1362 	struct stm32_i2s_data *i2s = dev_get_drvdata(dev);
1363 
1364 	regcache_cache_only(i2s->regmap, true);
1365 	regcache_mark_dirty(i2s->regmap);
1366 
1367 	return 0;
1368 }
1369 
stm32_i2s_resume(struct device * dev)1370 static int stm32_i2s_resume(struct device *dev)
1371 {
1372 	struct stm32_i2s_data *i2s = dev_get_drvdata(dev);
1373 
1374 	regcache_cache_only(i2s->regmap, false);
1375 	return regcache_sync(i2s->regmap);
1376 }
1377 
1378 static const struct dev_pm_ops stm32_i2s_pm_ops = {
1379 	SYSTEM_SLEEP_PM_OPS(stm32_i2s_suspend, stm32_i2s_resume)
1380 };
1381 
1382 static struct platform_driver stm32_i2s_driver = {
1383 	.driver = {
1384 		.name = "st,stm32-i2s",
1385 		.of_match_table = stm32_i2s_ids,
1386 		.pm = pm_ptr(&stm32_i2s_pm_ops),
1387 	},
1388 	.probe = stm32_i2s_probe,
1389 	.remove = stm32_i2s_remove,
1390 };
1391 
1392 module_platform_driver(stm32_i2s_driver);
1393 
1394 MODULE_DESCRIPTION("STM32 Soc i2s Interface");
1395 MODULE_AUTHOR("Olivier Moysan, <olivier.moysan@st.com>");
1396 MODULE_ALIAS("platform:stm32-i2s");
1397 MODULE_LICENSE("GPL v2");
1398