xref: /linux/sound/soc/stm/stm32_i2s.c (revision 0ebbab41fba1bae6ccd96c0eec17026700ac6534)
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 		return ret;
474 
475 	mclk->freq = req->best_parent_rate / i2s->divider;
476 
477 	req->rate = mclk->freq;
478 
479 	return 0;
480 }
481 
stm32_i2smclk_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)482 static unsigned long stm32_i2smclk_recalc_rate(struct clk_hw *hw,
483 					       unsigned long parent_rate)
484 {
485 	struct stm32_i2smclk_data *mclk = to_mclk_data(hw);
486 
487 	return mclk->freq;
488 }
489 
stm32_i2smclk_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)490 static int stm32_i2smclk_set_rate(struct clk_hw *hw, unsigned long rate,
491 				  unsigned long parent_rate)
492 {
493 	struct stm32_i2smclk_data *mclk = to_mclk_data(hw);
494 	struct stm32_i2s_data *i2s = mclk->i2s_data;
495 	int ret;
496 
497 	ret = stm32_i2s_calc_clk_div(i2s, parent_rate, rate);
498 	if (ret)
499 		return ret;
500 
501 	ret = stm32_i2s_set_clk_div(i2s);
502 	if (ret)
503 		return ret;
504 
505 	mclk->freq = rate;
506 
507 	return 0;
508 }
509 
stm32_i2smclk_enable(struct clk_hw * hw)510 static int stm32_i2smclk_enable(struct clk_hw *hw)
511 {
512 	struct stm32_i2smclk_data *mclk = to_mclk_data(hw);
513 	struct stm32_i2s_data *i2s = mclk->i2s_data;
514 
515 	dev_dbg(&i2s->pdev->dev, "Enable master clock\n");
516 
517 	return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
518 				    I2S_CGFR_MCKOE, I2S_CGFR_MCKOE);
519 }
520 
stm32_i2smclk_disable(struct clk_hw * hw)521 static void stm32_i2smclk_disable(struct clk_hw *hw)
522 {
523 	struct stm32_i2smclk_data *mclk = to_mclk_data(hw);
524 	struct stm32_i2s_data *i2s = mclk->i2s_data;
525 
526 	dev_dbg(&i2s->pdev->dev, "Disable master clock\n");
527 
528 	regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG, I2S_CGFR_MCKOE, 0);
529 }
530 
531 static const struct clk_ops mclk_ops = {
532 	.enable = stm32_i2smclk_enable,
533 	.disable = stm32_i2smclk_disable,
534 	.recalc_rate = stm32_i2smclk_recalc_rate,
535 	.determine_rate = stm32_i2smclk_determine_rate,
536 	.set_rate = stm32_i2smclk_set_rate,
537 };
538 
stm32_i2s_add_mclk_provider(struct stm32_i2s_data * i2s)539 static int stm32_i2s_add_mclk_provider(struct stm32_i2s_data *i2s)
540 {
541 	struct clk_hw *hw;
542 	struct stm32_i2smclk_data *mclk;
543 	struct device *dev = &i2s->pdev->dev;
544 	const char *pname = __clk_get_name(i2s->i2sclk);
545 	char *mclk_name, *p, *s = (char *)pname;
546 	int ret, i = 0;
547 
548 	mclk = devm_kzalloc(dev, sizeof(*mclk), GFP_KERNEL);
549 	if (!mclk)
550 		return -ENOMEM;
551 
552 	mclk_name = devm_kcalloc(dev, sizeof(char),
553 				 STM32_I2S_NAME_LEN, GFP_KERNEL);
554 	if (!mclk_name)
555 		return -ENOMEM;
556 
557 	/*
558 	 * Forge mclk clock name from parent clock name and suffix.
559 	 * String after "_" char is stripped in parent name.
560 	 */
561 	p = mclk_name;
562 	while (*s && *s != '_' && (i < (STM32_I2S_NAME_LEN - 7))) {
563 		*p++ = *s++;
564 		i++;
565 	}
566 	strcat(p, "_mclk");
567 
568 	mclk->hw.init = CLK_HW_INIT(mclk_name, pname, &mclk_ops, 0);
569 	mclk->i2s_data = i2s;
570 	hw = &mclk->hw;
571 
572 	dev_dbg(dev, "Register master clock %s\n", mclk_name);
573 	ret = devm_clk_hw_register(&i2s->pdev->dev, hw);
574 	if (ret) {
575 		dev_err(dev, "mclk register fails with error %d\n", ret);
576 		return ret;
577 	}
578 	i2s->i2smclk = hw->clk;
579 
580 	/* register mclk provider */
581 	return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get, hw);
582 }
583 
stm32_i2s_isr(int irq,void * devid)584 static irqreturn_t stm32_i2s_isr(int irq, void *devid)
585 {
586 	struct stm32_i2s_data *i2s = (struct stm32_i2s_data *)devid;
587 	struct platform_device *pdev = i2s->pdev;
588 	u32 sr, ier;
589 	unsigned long flags;
590 	int err = 0;
591 
592 	regmap_read(i2s->regmap, STM32_I2S_SR_REG, &sr);
593 	regmap_read(i2s->regmap, STM32_I2S_IER_REG, &ier);
594 
595 	flags = sr & ier;
596 	if (!flags) {
597 		dev_dbg(&pdev->dev, "Spurious IRQ sr=0x%08x, ier=0x%08x\n",
598 			sr, ier);
599 		return IRQ_NONE;
600 	}
601 
602 	regmap_write_bits(i2s->regmap, STM32_I2S_IFCR_REG,
603 			  I2S_IFCR_MASK, flags);
604 
605 	if (flags & I2S_SR_OVR) {
606 		dev_dbg(&pdev->dev, "Overrun\n");
607 		err = 1;
608 	}
609 
610 	if (flags & I2S_SR_UDR) {
611 		dev_dbg(&pdev->dev, "Underrun\n");
612 		err = 1;
613 	}
614 
615 	if (flags & I2S_SR_TIFRE)
616 		dev_dbg(&pdev->dev, "Frame error\n");
617 
618 	spin_lock(&i2s->irq_lock);
619 	if (err && i2s->substream)
620 		snd_pcm_stop_xrun(i2s->substream);
621 	spin_unlock(&i2s->irq_lock);
622 
623 	return IRQ_HANDLED;
624 }
625 
stm32_i2s_readable_reg(struct device * dev,unsigned int reg)626 static bool stm32_i2s_readable_reg(struct device *dev, unsigned int reg)
627 {
628 	switch (reg) {
629 	case STM32_I2S_CR1_REG:
630 	case STM32_I2S_CFG1_REG:
631 	case STM32_I2S_CFG2_REG:
632 	case STM32_I2S_IER_REG:
633 	case STM32_I2S_SR_REG:
634 	case STM32_I2S_RXDR_REG:
635 	case STM32_I2S_CGFR_REG:
636 	case STM32_I2S_HWCFGR_REG:
637 	case STM32_I2S_VERR_REG:
638 	case STM32_I2S_IPIDR_REG:
639 	case STM32_I2S_SIDR_REG:
640 		return true;
641 	default:
642 		return false;
643 	}
644 }
645 
stm32_i2s_volatile_reg(struct device * dev,unsigned int reg)646 static bool stm32_i2s_volatile_reg(struct device *dev, unsigned int reg)
647 {
648 	switch (reg) {
649 	case STM32_I2S_SR_REG:
650 	case STM32_I2S_RXDR_REG:
651 		return true;
652 	default:
653 		return false;
654 	}
655 }
656 
stm32_i2s_writeable_reg(struct device * dev,unsigned int reg)657 static bool stm32_i2s_writeable_reg(struct device *dev, unsigned int reg)
658 {
659 	switch (reg) {
660 	case STM32_I2S_CR1_REG:
661 	case STM32_I2S_CFG1_REG:
662 	case STM32_I2S_CFG2_REG:
663 	case STM32_I2S_IER_REG:
664 	case STM32_I2S_IFCR_REG:
665 	case STM32_I2S_TXDR_REG:
666 	case STM32_I2S_CGFR_REG:
667 		return true;
668 	default:
669 		return false;
670 	}
671 }
672 
stm32_i2s_set_dai_fmt(struct snd_soc_dai * cpu_dai,unsigned int fmt)673 static int stm32_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
674 {
675 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
676 	u32 cgfr;
677 	u32 cgfr_mask =  I2S_CGFR_I2SSTD_MASK | I2S_CGFR_CKPOL |
678 			 I2S_CGFR_WSINV | I2S_CGFR_I2SCFG_MASK;
679 
680 	dev_dbg(cpu_dai->dev, "fmt %x\n", fmt);
681 
682 	/*
683 	 * winv = 0 : default behavior (high/low) for all standards
684 	 * ckpol = 0 for all standards.
685 	 */
686 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
687 	case SND_SOC_DAIFMT_I2S:
688 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_I2S);
689 		break;
690 	case SND_SOC_DAIFMT_MSB:
691 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_LEFT_J);
692 		break;
693 	case SND_SOC_DAIFMT_LSB:
694 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_RIGHT_J);
695 		break;
696 	case SND_SOC_DAIFMT_DSP_A:
697 		cgfr = I2S_CGFR_I2SSTD_SET(I2S_STD_DSP);
698 		break;
699 	/* DSP_B not mapped on I2S PCM long format. 1 bit offset does not fit */
700 	default:
701 		dev_err(cpu_dai->dev, "Unsupported protocol %#x\n",
702 			fmt & SND_SOC_DAIFMT_FORMAT_MASK);
703 		return -EINVAL;
704 	}
705 
706 	/* DAI clock strobing */
707 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
708 	case SND_SOC_DAIFMT_NB_NF:
709 		break;
710 	case SND_SOC_DAIFMT_IB_NF:
711 		cgfr |= I2S_CGFR_CKPOL;
712 		break;
713 	case SND_SOC_DAIFMT_NB_IF:
714 		cgfr |= I2S_CGFR_WSINV;
715 		break;
716 	case SND_SOC_DAIFMT_IB_IF:
717 		cgfr |= I2S_CGFR_CKPOL;
718 		cgfr |= I2S_CGFR_WSINV;
719 		break;
720 	default:
721 		dev_err(cpu_dai->dev, "Unsupported strobing %#x\n",
722 			fmt & SND_SOC_DAIFMT_INV_MASK);
723 		return -EINVAL;
724 	}
725 
726 	/* DAI clock master masks */
727 	switch (fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) {
728 	case SND_SOC_DAIFMT_BC_FC:
729 		i2s->ms_flg = I2S_MS_SLAVE;
730 		break;
731 	case SND_SOC_DAIFMT_BP_FP:
732 		i2s->ms_flg = I2S_MS_MASTER;
733 		break;
734 	default:
735 		dev_err(cpu_dai->dev, "Unsupported mode %#x\n",
736 			fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK);
737 		return -EINVAL;
738 	}
739 
740 	i2s->fmt = fmt;
741 	return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
742 				  cgfr_mask, cgfr);
743 }
744 
stm32_i2s_set_sysclk(struct snd_soc_dai * cpu_dai,int clk_id,unsigned int freq,int dir)745 static int stm32_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
746 				int clk_id, unsigned int freq, int dir)
747 {
748 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
749 	int ret = 0;
750 
751 	dev_dbg(cpu_dai->dev, "I2S MCLK frequency is %uHz. mode: %s, dir: %s\n",
752 		freq, STM32_I2S_IS_MASTER(i2s) ? "master" : "slave",
753 		dir ? "output" : "input");
754 
755 	/* MCLK generation is available only in master mode */
756 	if (dir == SND_SOC_CLOCK_OUT && STM32_I2S_IS_MASTER(i2s)) {
757 		if (!i2s->i2smclk) {
758 			dev_dbg(cpu_dai->dev, "No MCLK registered\n");
759 			return 0;
760 		}
761 
762 		/* Assume shutdown if requested frequency is 0Hz */
763 		if (!freq) {
764 			/* Release mclk rate only if rate was actually set */
765 			if (i2s->mclk_rate) {
766 				clk_rate_exclusive_put(i2s->i2smclk);
767 				i2s->mclk_rate = 0;
768 			}
769 
770 			if (i2s->put_i2s_clk_rate)
771 				i2s->put_i2s_clk_rate(i2s);
772 
773 			return regmap_update_bits(i2s->regmap,
774 						  STM32_I2S_CGFR_REG,
775 						  I2S_CGFR_MCKOE, 0);
776 		}
777 		/* If master clock is used, set parent clock now */
778 		ret = i2s->set_i2s_clk_rate(i2s, freq);
779 		if (ret)
780 			return ret;
781 		ret = clk_set_rate_exclusive(i2s->i2smclk, freq);
782 		if (ret) {
783 			dev_err(cpu_dai->dev, "Could not set mclk rate\n");
784 			return ret;
785 		}
786 		ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
787 					 I2S_CGFR_MCKOE, I2S_CGFR_MCKOE);
788 		if (!ret)
789 			i2s->mclk_rate = freq;
790 	}
791 
792 	return ret;
793 }
794 
stm32_i2s_configure_clock(struct snd_soc_dai * cpu_dai,struct snd_pcm_hw_params * params)795 static int stm32_i2s_configure_clock(struct snd_soc_dai *cpu_dai,
796 				     struct snd_pcm_hw_params *params)
797 {
798 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
799 	unsigned long i2s_clock_rate;
800 	unsigned int nb_bits, frame_len;
801 	unsigned int rate = params_rate(params);
802 	u32 cgfr;
803 	int ret;
804 
805 	if (!i2s->mclk_rate) {
806 		ret = i2s->set_i2s_clk_rate(i2s, rate);
807 		if (ret)
808 			return ret;
809 	}
810 	i2s_clock_rate = clk_get_rate(i2s->i2sclk);
811 
812 	/*
813 	 * mckl = mclk_ratio x ws
814 	 *   i2s mode : mclk_ratio = 256
815 	 *   dsp mode : mclk_ratio = 128
816 	 *
817 	 * mclk on
818 	 *   i2s mode : div = i2s_clk / (mclk_ratio * ws)
819 	 *   dsp mode : div = i2s_clk / (mclk_ratio * ws)
820 	 * mclk off
821 	 *   i2s mode : div = i2s_clk / (nb_bits x ws)
822 	 *   dsp mode : div = i2s_clk / (nb_bits x ws)
823 	 */
824 	if (i2s->mclk_rate) {
825 		ret = stm32_i2s_calc_clk_div(i2s, i2s_clock_rate,
826 					     i2s->mclk_rate);
827 		if (ret)
828 			return ret;
829 	} else {
830 		frame_len = 32;
831 		if ((i2s->fmt & SND_SOC_DAIFMT_FORMAT_MASK) ==
832 		    SND_SOC_DAIFMT_DSP_A)
833 			frame_len = 16;
834 
835 		/* master clock not enabled */
836 		ret = regmap_read(i2s->regmap, STM32_I2S_CGFR_REG, &cgfr);
837 		if (ret < 0)
838 			return ret;
839 
840 		nb_bits = frame_len * (FIELD_GET(I2S_CGFR_CHLEN, cgfr) + 1);
841 		ret = stm32_i2s_calc_clk_div(i2s, i2s_clock_rate,
842 					     (nb_bits * rate));
843 		if (ret)
844 			return ret;
845 	}
846 
847 	ret = stm32_i2s_set_clk_div(i2s);
848 	if (ret < 0)
849 		return ret;
850 
851 	/* Set bitclock and frameclock to their inactive state */
852 	return regmap_update_bits(i2s->regmap, STM32_I2S_CFG2_REG,
853 				  I2S_CFG2_AFCNTR, I2S_CFG2_AFCNTR);
854 }
855 
stm32_i2s_configure(struct snd_soc_dai * cpu_dai,struct snd_pcm_hw_params * params,struct snd_pcm_substream * substream)856 static int stm32_i2s_configure(struct snd_soc_dai *cpu_dai,
857 			       struct snd_pcm_hw_params *params,
858 			       struct snd_pcm_substream *substream)
859 {
860 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
861 	int format = params_width(params);
862 	u32 cfgr, cfgr_mask, cfg1;
863 	unsigned int fthlv;
864 	int ret;
865 
866 	switch (format) {
867 	case 16:
868 		cfgr = I2S_CGFR_DATLEN_SET(I2S_I2SMOD_DATLEN_16);
869 		cfgr_mask = I2S_CGFR_DATLEN_MASK | I2S_CGFR_CHLEN;
870 		break;
871 	case 32:
872 		cfgr = I2S_CGFR_DATLEN_SET(I2S_I2SMOD_DATLEN_32) |
873 					   I2S_CGFR_CHLEN;
874 		cfgr_mask = I2S_CGFR_DATLEN_MASK | I2S_CGFR_CHLEN;
875 		break;
876 	default:
877 		dev_err(cpu_dai->dev, "Unexpected format %d", format);
878 		return -EINVAL;
879 	}
880 
881 	if (STM32_I2S_IS_SLAVE(i2s)) {
882 		cfgr |= I2S_CGFR_I2SCFG_SET(I2S_I2SMOD_FD_SLAVE);
883 
884 		/* As data length is either 16 or 32 bits, fixch always set */
885 		cfgr |= I2S_CGFR_FIXCH;
886 		cfgr_mask |= I2S_CGFR_FIXCH;
887 	} else {
888 		cfgr |= I2S_CGFR_I2SCFG_SET(I2S_I2SMOD_FD_MASTER);
889 	}
890 	cfgr_mask |= I2S_CGFR_I2SCFG_MASK;
891 
892 	ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
893 				 cfgr_mask, cfgr);
894 	if (ret < 0)
895 		return ret;
896 
897 	fthlv = STM32_I2S_FIFO_SIZE * I2S_FIFO_TH_ONE_QUARTER / 4;
898 	cfg1 = I2S_CFG1_FTHVL_SET(fthlv - 1);
899 
900 	return regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
901 				  I2S_CFG1_FTHVL_MASK, cfg1);
902 }
903 
stm32_i2s_startup(struct snd_pcm_substream * substream,struct snd_soc_dai * cpu_dai)904 static int stm32_i2s_startup(struct snd_pcm_substream *substream,
905 			     struct snd_soc_dai *cpu_dai)
906 {
907 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
908 	unsigned long flags;
909 	int ret;
910 
911 	spin_lock_irqsave(&i2s->irq_lock, flags);
912 	i2s->substream = substream;
913 	spin_unlock_irqrestore(&i2s->irq_lock, flags);
914 
915 	if ((i2s->fmt & SND_SOC_DAIFMT_FORMAT_MASK) != SND_SOC_DAIFMT_DSP_A)
916 		snd_pcm_hw_constraint_single(substream->runtime,
917 					     SNDRV_PCM_HW_PARAM_CHANNELS, 2);
918 
919 	ret = clk_prepare_enable(i2s->i2sclk);
920 	if (ret < 0) {
921 		dev_err(cpu_dai->dev, "Failed to enable clock: %d\n", ret);
922 		return ret;
923 	}
924 
925 	return regmap_write_bits(i2s->regmap, STM32_I2S_IFCR_REG,
926 				 I2S_IFCR_MASK, I2S_IFCR_MASK);
927 }
928 
stm32_i2s_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params,struct snd_soc_dai * cpu_dai)929 static int stm32_i2s_hw_params(struct snd_pcm_substream *substream,
930 			       struct snd_pcm_hw_params *params,
931 			       struct snd_soc_dai *cpu_dai)
932 {
933 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
934 	int ret;
935 
936 	ret = stm32_i2s_configure(cpu_dai, params, substream);
937 	if (ret < 0) {
938 		dev_err(cpu_dai->dev, "Configuration returned error %d\n", ret);
939 		return ret;
940 	}
941 
942 	if (STM32_I2S_IS_MASTER(i2s))
943 		ret = stm32_i2s_configure_clock(cpu_dai, params);
944 
945 	return ret;
946 }
947 
stm32_i2s_trigger(struct snd_pcm_substream * substream,int cmd,struct snd_soc_dai * cpu_dai)948 static int stm32_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
949 			     struct snd_soc_dai *cpu_dai)
950 {
951 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
952 	bool playback_flg = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK);
953 	u32 cfg1_mask, ier;
954 	int ret;
955 
956 	switch (cmd) {
957 	case SNDRV_PCM_TRIGGER_START:
958 	case SNDRV_PCM_TRIGGER_RESUME:
959 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
960 		/* Enable i2s */
961 		dev_dbg(cpu_dai->dev, "start I2S %s\n",
962 			snd_pcm_direction_name(substream->stream));
963 
964 		cfg1_mask = I2S_CFG1_RXDMAEN | I2S_CFG1_TXDMAEN;
965 		regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
966 				   cfg1_mask, cfg1_mask);
967 
968 		ret = regmap_update_bits(i2s->regmap, STM32_I2S_CR1_REG,
969 					 I2S_CR1_SPE, I2S_CR1_SPE);
970 		if (ret < 0) {
971 			dev_err(cpu_dai->dev, "Error %d enabling I2S\n", ret);
972 			return ret;
973 		}
974 
975 		ret = regmap_write_bits(i2s->regmap, STM32_I2S_CR1_REG,
976 					I2S_CR1_CSTART, I2S_CR1_CSTART);
977 		if (ret < 0) {
978 			dev_err(cpu_dai->dev, "Error %d starting I2S\n", ret);
979 			return ret;
980 		}
981 
982 		regmap_write_bits(i2s->regmap, STM32_I2S_IFCR_REG,
983 				  I2S_IFCR_MASK, I2S_IFCR_MASK);
984 
985 		spin_lock(&i2s->lock_fd);
986 		i2s->refcount++;
987 		if (playback_flg) {
988 			ier = I2S_IER_UDRIE;
989 		} else {
990 			ier = I2S_IER_OVRIE;
991 
992 			if (STM32_I2S_IS_MASTER(i2s) && i2s->refcount == 1)
993 				/* dummy write to gate bus clocks */
994 				regmap_write(i2s->regmap,
995 					     STM32_I2S_TXDR_REG, 0);
996 		}
997 		spin_unlock(&i2s->lock_fd);
998 
999 		if (STM32_I2S_IS_SLAVE(i2s))
1000 			ier |= I2S_IER_TIFREIE;
1001 
1002 		regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG, ier, ier);
1003 		break;
1004 	case SNDRV_PCM_TRIGGER_STOP:
1005 	case SNDRV_PCM_TRIGGER_SUSPEND:
1006 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1007 		dev_dbg(cpu_dai->dev, "stop I2S %s\n",
1008 			snd_pcm_direction_name(substream->stream));
1009 
1010 		if (playback_flg)
1011 			regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG,
1012 					   I2S_IER_UDRIE,
1013 					   (unsigned int)~I2S_IER_UDRIE);
1014 		else
1015 			regmap_update_bits(i2s->regmap, STM32_I2S_IER_REG,
1016 					   I2S_IER_OVRIE,
1017 					   (unsigned int)~I2S_IER_OVRIE);
1018 
1019 		spin_lock(&i2s->lock_fd);
1020 		i2s->refcount--;
1021 		if (i2s->refcount) {
1022 			spin_unlock(&i2s->lock_fd);
1023 			break;
1024 		}
1025 
1026 		ret = regmap_update_bits(i2s->regmap, STM32_I2S_CR1_REG,
1027 					 I2S_CR1_SPE, 0);
1028 		if (ret < 0) {
1029 			dev_err(cpu_dai->dev, "Error %d disabling I2S\n", ret);
1030 			spin_unlock(&i2s->lock_fd);
1031 			return ret;
1032 		}
1033 		spin_unlock(&i2s->lock_fd);
1034 
1035 		cfg1_mask = I2S_CFG1_RXDMAEN | I2S_CFG1_TXDMAEN;
1036 		regmap_update_bits(i2s->regmap, STM32_I2S_CFG1_REG,
1037 				   cfg1_mask, 0);
1038 		break;
1039 	default:
1040 		return -EINVAL;
1041 	}
1042 
1043 	return 0;
1044 }
1045 
stm32_i2s_shutdown(struct snd_pcm_substream * substream,struct snd_soc_dai * cpu_dai)1046 static void stm32_i2s_shutdown(struct snd_pcm_substream *substream,
1047 			       struct snd_soc_dai *cpu_dai)
1048 {
1049 	struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
1050 	unsigned long flags;
1051 
1052 	clk_disable_unprepare(i2s->i2sclk);
1053 
1054 	/*
1055 	 * Release kernel clock if following conditions are fulfilled
1056 	 * - Master clock is not used. Kernel clock won't be released trough sysclk
1057 	 * - Put handler is defined. Involve that clock is managed exclusively
1058 	 */
1059 	if (!i2s->i2smclk && i2s->put_i2s_clk_rate)
1060 		i2s->put_i2s_clk_rate(i2s);
1061 
1062 	spin_lock_irqsave(&i2s->irq_lock, flags);
1063 	i2s->substream = NULL;
1064 	spin_unlock_irqrestore(&i2s->irq_lock, flags);
1065 }
1066 
stm32_i2s_dai_probe(struct snd_soc_dai * cpu_dai)1067 static int stm32_i2s_dai_probe(struct snd_soc_dai *cpu_dai)
1068 {
1069 	struct stm32_i2s_data *i2s = dev_get_drvdata(cpu_dai->dev);
1070 	struct snd_dmaengine_dai_dma_data *dma_data_tx = &i2s->dma_data_tx;
1071 	struct snd_dmaengine_dai_dma_data *dma_data_rx = &i2s->dma_data_rx;
1072 
1073 	/* Buswidth will be set by framework */
1074 	dma_data_tx->addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
1075 	dma_data_tx->addr = (dma_addr_t)(i2s->phys_addr) + STM32_I2S_TXDR_REG;
1076 	dma_data_tx->maxburst = 1;
1077 	dma_data_rx->addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
1078 	dma_data_rx->addr = (dma_addr_t)(i2s->phys_addr) + STM32_I2S_RXDR_REG;
1079 	dma_data_rx->maxburst = 1;
1080 
1081 	snd_soc_dai_init_dma_data(cpu_dai, dma_data_tx, dma_data_rx);
1082 
1083 	return 0;
1084 }
1085 
1086 static const struct regmap_config stm32_h7_i2s_regmap_conf = {
1087 	.reg_bits = 32,
1088 	.reg_stride = 4,
1089 	.val_bits = 32,
1090 	.max_register = STM32_I2S_SIDR_REG,
1091 	.readable_reg = stm32_i2s_readable_reg,
1092 	.volatile_reg = stm32_i2s_volatile_reg,
1093 	.writeable_reg = stm32_i2s_writeable_reg,
1094 	.num_reg_defaults_raw = STM32_I2S_SIDR_REG / sizeof(u32) + 1,
1095 	.fast_io = true,
1096 	.cache_type = REGCACHE_FLAT,
1097 };
1098 
1099 static const struct snd_soc_dai_ops stm32_i2s_pcm_dai_ops = {
1100 	.probe		= stm32_i2s_dai_probe,
1101 	.set_sysclk	= stm32_i2s_set_sysclk,
1102 	.set_fmt	= stm32_i2s_set_dai_fmt,
1103 	.startup	= stm32_i2s_startup,
1104 	.hw_params	= stm32_i2s_hw_params,
1105 	.trigger	= stm32_i2s_trigger,
1106 	.shutdown	= stm32_i2s_shutdown,
1107 };
1108 
1109 static const struct snd_pcm_hardware stm32_i2s_pcm_hw = {
1110 	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_MMAP,
1111 	.buffer_bytes_max = 8 * PAGE_SIZE,
1112 	.period_bytes_min = 1024,
1113 	.period_bytes_max = 4 * PAGE_SIZE,
1114 	.periods_min = 2,
1115 	.periods_max = 8,
1116 };
1117 
1118 static const struct snd_dmaengine_pcm_config stm32_i2s_pcm_config = {
1119 	.pcm_hardware	= &stm32_i2s_pcm_hw,
1120 	.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
1121 	.prealloc_buffer_size = PAGE_SIZE * 8,
1122 };
1123 
1124 static const struct snd_soc_component_driver stm32_i2s_component = {
1125 	.name = "stm32-i2s",
1126 	.legacy_dai_naming = 1,
1127 };
1128 
stm32_i2s_dai_init(struct snd_soc_pcm_stream * stream,char * stream_name)1129 static void stm32_i2s_dai_init(struct snd_soc_pcm_stream *stream,
1130 			       char *stream_name)
1131 {
1132 	stream->stream_name = stream_name;
1133 	stream->channels_min = 1;
1134 	stream->channels_max = 2;
1135 	stream->rates = SNDRV_PCM_RATE_8000_192000;
1136 	stream->formats = SNDRV_PCM_FMTBIT_S16_LE |
1137 				   SNDRV_PCM_FMTBIT_S32_LE;
1138 }
1139 
stm32_i2s_dais_init(struct platform_device * pdev,struct stm32_i2s_data * i2s)1140 static int stm32_i2s_dais_init(struct platform_device *pdev,
1141 			       struct stm32_i2s_data *i2s)
1142 {
1143 	struct snd_soc_dai_driver *dai_ptr;
1144 
1145 	dai_ptr = devm_kzalloc(&pdev->dev, sizeof(struct snd_soc_dai_driver),
1146 			       GFP_KERNEL);
1147 	if (!dai_ptr)
1148 		return -ENOMEM;
1149 
1150 	dai_ptr->ops = &stm32_i2s_pcm_dai_ops;
1151 	dai_ptr->id = 1;
1152 	stm32_i2s_dai_init(&dai_ptr->playback, "playback");
1153 	stm32_i2s_dai_init(&dai_ptr->capture, "capture");
1154 	i2s->dai_drv = dai_ptr;
1155 
1156 	return 0;
1157 }
1158 
1159 static const struct stm32_i2s_conf stm32_i2s_conf_h7 = {
1160 	.regmap_conf = &stm32_h7_i2s_regmap_conf,
1161 	.get_i2s_clk_parent = stm32_i2s_get_parent_clk,
1162 };
1163 
1164 static const struct stm32_i2s_conf stm32_i2s_conf_mp25 = {
1165 	.regmap_conf = &stm32_h7_i2s_regmap_conf
1166 };
1167 
1168 static const struct of_device_id stm32_i2s_ids[] = {
1169 	{ .compatible = "st,stm32h7-i2s", .data = &stm32_i2s_conf_h7 },
1170 	{ .compatible = "st,stm32mp25-i2s", .data = &stm32_i2s_conf_mp25 },
1171 	{},
1172 };
1173 
stm32_i2s_get_parent_clk(struct stm32_i2s_data * i2s)1174 static int stm32_i2s_get_parent_clk(struct stm32_i2s_data *i2s)
1175 {
1176 	struct device *dev = &i2s->pdev->dev;
1177 
1178 	i2s->x8kclk = devm_clk_get(dev, "x8k");
1179 	if (IS_ERR(i2s->x8kclk))
1180 		return dev_err_probe(dev, PTR_ERR(i2s->x8kclk), "Cannot get x8k parent clock\n");
1181 
1182 	i2s->x11kclk = devm_clk_get(dev, "x11k");
1183 	if (IS_ERR(i2s->x11kclk))
1184 		return dev_err_probe(dev, PTR_ERR(i2s->x11kclk), "Cannot get x11k parent clock\n");
1185 
1186 	return 0;
1187 }
1188 
stm32_i2s_parse_dt(struct platform_device * pdev,struct stm32_i2s_data * i2s)1189 static int stm32_i2s_parse_dt(struct platform_device *pdev,
1190 			      struct stm32_i2s_data *i2s)
1191 {
1192 	struct device_node *np = pdev->dev.of_node;
1193 	struct reset_control *rst;
1194 	struct resource *res;
1195 	int irq, ret;
1196 
1197 	if (!np)
1198 		return -ENODEV;
1199 
1200 	i2s->conf = device_get_match_data(&pdev->dev);
1201 	if (!i2s->conf)
1202 		return -EINVAL;
1203 
1204 	i2s->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1205 	if (IS_ERR(i2s->base))
1206 		return PTR_ERR(i2s->base);
1207 
1208 	i2s->phys_addr = res->start;
1209 
1210 	/* Get clocks */
1211 	i2s->pclk = devm_clk_get(&pdev->dev, "pclk");
1212 	if (IS_ERR(i2s->pclk))
1213 		return dev_err_probe(&pdev->dev, PTR_ERR(i2s->pclk),
1214 				     "Could not get pclk\n");
1215 
1216 	i2s->i2sclk = devm_clk_get(&pdev->dev, "i2sclk");
1217 	if (IS_ERR(i2s->i2sclk))
1218 		return dev_err_probe(&pdev->dev, PTR_ERR(i2s->i2sclk),
1219 				     "Could not get i2sclk\n");
1220 
1221 	if (i2s->conf->get_i2s_clk_parent) {
1222 		i2s->set_i2s_clk_rate = stm32_i2s_set_parent_clock;
1223 	} else {
1224 		i2s->set_i2s_clk_rate = stm32_i2s_set_parent_rate;
1225 		i2s->put_i2s_clk_rate = stm32_i2s_put_parent_rate;
1226 	}
1227 
1228 	if (i2s->conf->get_i2s_clk_parent) {
1229 		ret = i2s->conf->get_i2s_clk_parent(i2s);
1230 		if (ret)
1231 			return ret;
1232 	}
1233 
1234 	/* Register mclk provider if requested */
1235 	if (of_property_present(np, "#clock-cells")) {
1236 		ret = stm32_i2s_add_mclk_provider(i2s);
1237 		if (ret < 0)
1238 			return ret;
1239 	}
1240 
1241 	/* Get irqs */
1242 	irq = platform_get_irq(pdev, 0);
1243 	if (irq < 0)
1244 		return irq;
1245 
1246 	ret = devm_request_irq(&pdev->dev, irq, stm32_i2s_isr, 0,
1247 			       dev_name(&pdev->dev), i2s);
1248 	if (ret) {
1249 		dev_err(&pdev->dev, "irq request returned %d\n", ret);
1250 		return ret;
1251 	}
1252 
1253 	/* Reset */
1254 	rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
1255 	if (IS_ERR(rst))
1256 		return dev_err_probe(&pdev->dev, PTR_ERR(rst),
1257 				     "Reset controller error\n");
1258 
1259 	reset_control_assert(rst);
1260 	udelay(2);
1261 	reset_control_deassert(rst);
1262 
1263 	return 0;
1264 }
1265 
stm32_i2s_remove(struct platform_device * pdev)1266 static void stm32_i2s_remove(struct platform_device *pdev)
1267 {
1268 	snd_dmaengine_pcm_unregister(&pdev->dev);
1269 	snd_soc_unregister_component(&pdev->dev);
1270 	pm_runtime_disable(&pdev->dev);
1271 }
1272 
stm32_i2s_probe(struct platform_device * pdev)1273 static int stm32_i2s_probe(struct platform_device *pdev)
1274 {
1275 	struct stm32_i2s_data *i2s;
1276 	u32 val;
1277 	int ret;
1278 
1279 	i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
1280 	if (!i2s)
1281 		return -ENOMEM;
1282 
1283 	i2s->pdev = pdev;
1284 	i2s->ms_flg = I2S_MS_NOT_SET;
1285 	spin_lock_init(&i2s->lock_fd);
1286 	spin_lock_init(&i2s->irq_lock);
1287 	platform_set_drvdata(pdev, i2s);
1288 
1289 	ret = stm32_i2s_parse_dt(pdev, i2s);
1290 	if (ret)
1291 		return ret;
1292 
1293 	ret = stm32_i2s_dais_init(pdev, i2s);
1294 	if (ret)
1295 		return ret;
1296 
1297 	i2s->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "pclk",
1298 						i2s->base, i2s->conf->regmap_conf);
1299 	if (IS_ERR(i2s->regmap))
1300 		return dev_err_probe(&pdev->dev, PTR_ERR(i2s->regmap),
1301 				     "Regmap init error\n");
1302 
1303 	ret = snd_dmaengine_pcm_register(&pdev->dev, &stm32_i2s_pcm_config, 0);
1304 	if (ret)
1305 		return dev_err_probe(&pdev->dev, ret, "PCM DMA register error\n");
1306 
1307 	ret = snd_soc_register_component(&pdev->dev, &stm32_i2s_component,
1308 					 i2s->dai_drv, 1);
1309 	if (ret) {
1310 		snd_dmaengine_pcm_unregister(&pdev->dev);
1311 		return ret;
1312 	}
1313 
1314 	/* Set SPI/I2S in i2s mode */
1315 	ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
1316 				 I2S_CGFR_I2SMOD, I2S_CGFR_I2SMOD);
1317 	if (ret)
1318 		goto error;
1319 
1320 	ret = regmap_read(i2s->regmap, STM32_I2S_IPIDR_REG, &val);
1321 	if (ret)
1322 		goto error;
1323 
1324 	if (val == I2S_IPIDR_NUMBER) {
1325 		ret = regmap_read(i2s->regmap, STM32_I2S_HWCFGR_REG, &val);
1326 		if (ret)
1327 			goto error;
1328 
1329 		if (!FIELD_GET(I2S_HWCFGR_I2S_SUPPORT_MASK, val)) {
1330 			dev_err(&pdev->dev,
1331 				"Device does not support i2s mode\n");
1332 			ret = -EPERM;
1333 			goto error;
1334 		}
1335 
1336 		ret = regmap_read(i2s->regmap, STM32_I2S_VERR_REG, &val);
1337 		if (ret)
1338 			goto error;
1339 
1340 		dev_dbg(&pdev->dev, "I2S version: %lu.%lu registered\n",
1341 			FIELD_GET(I2S_VERR_MAJ_MASK, val),
1342 			FIELD_GET(I2S_VERR_MIN_MASK, val));
1343 	}
1344 
1345 	pm_runtime_enable(&pdev->dev);
1346 
1347 	return ret;
1348 
1349 error:
1350 	stm32_i2s_remove(pdev);
1351 
1352 	return ret;
1353 }
1354 
1355 MODULE_DEVICE_TABLE(of, stm32_i2s_ids);
1356 
stm32_i2s_suspend(struct device * dev)1357 static int stm32_i2s_suspend(struct device *dev)
1358 {
1359 	struct stm32_i2s_data *i2s = dev_get_drvdata(dev);
1360 
1361 	regcache_cache_only(i2s->regmap, true);
1362 	regcache_mark_dirty(i2s->regmap);
1363 
1364 	return 0;
1365 }
1366 
stm32_i2s_resume(struct device * dev)1367 static int stm32_i2s_resume(struct device *dev)
1368 {
1369 	struct stm32_i2s_data *i2s = dev_get_drvdata(dev);
1370 
1371 	regcache_cache_only(i2s->regmap, false);
1372 	return regcache_sync(i2s->regmap);
1373 }
1374 
1375 static const struct dev_pm_ops stm32_i2s_pm_ops = {
1376 	SYSTEM_SLEEP_PM_OPS(stm32_i2s_suspend, stm32_i2s_resume)
1377 };
1378 
1379 static struct platform_driver stm32_i2s_driver = {
1380 	.driver = {
1381 		.name = "st,stm32-i2s",
1382 		.of_match_table = stm32_i2s_ids,
1383 		.pm = pm_ptr(&stm32_i2s_pm_ops),
1384 	},
1385 	.probe = stm32_i2s_probe,
1386 	.remove = stm32_i2s_remove,
1387 };
1388 
1389 module_platform_driver(stm32_i2s_driver);
1390 
1391 MODULE_DESCRIPTION("STM32 Soc i2s Interface");
1392 MODULE_AUTHOR("Olivier Moysan, <olivier.moysan@st.com>");
1393 MODULE_ALIAS("platform:stm32-i2s");
1394 MODULE_LICENSE("GPL v2");
1395