xref: /linux/sound/soc/fsl/fsl_ssi.c (revision add4b1b02da7e7ec35c34dd04d351ac53f3f0dd8)
1 /*
2  * Freescale SSI ALSA SoC Digital Audio Interface (DAI) driver
3  *
4  * Author: Timur Tabi <timur@freescale.com>
5  *
6  * Copyright 2007-2010 Freescale Semiconductor, Inc.
7  *
8  * This file is licensed under the terms of the GNU General Public License
9  * version 2.  This program is licensed "as is" without any warranty of any
10  * kind, whether express or implied.
11  *
12  *
13  * Some notes why imx-pcm-fiq is used instead of DMA on some boards:
14  *
15  * The i.MX SSI core has some nasty limitations in AC97 mode. While most
16  * sane processor vendors have a FIFO per AC97 slot, the i.MX has only
17  * one FIFO which combines all valid receive slots. We cannot even select
18  * which slots we want to receive. The WM9712 with which this driver
19  * was developed with always sends GPIO status data in slot 12 which
20  * we receive in our (PCM-) data stream. The only chance we have is to
21  * manually skip this data in the FIQ handler. With sampling rates different
22  * from 48000Hz not every frame has valid receive data, so the ratio
23  * between pcm data and GPIO status data changes. Our FIQ handler is not
24  * able to handle this, hence this driver only works with 48000Hz sampling
25  * rate.
26  * Reading and writing AC97 registers is another challenge. The core
27  * provides us status bits when the read register is updated with *another*
28  * value. When we read the same register two times (and the register still
29  * contains the same value) these status bits are not set. We work
30  * around this by not polling these bits but only wait a fixed delay.
31  */
32 
33 #include <linux/init.h>
34 #include <linux/io.h>
35 #include <linux/module.h>
36 #include <linux/interrupt.h>
37 #include <linux/clk.h>
38 #include <linux/device.h>
39 #include <linux/delay.h>
40 #include <linux/slab.h>
41 #include <linux/spinlock.h>
42 #include <linux/of.h>
43 #include <linux/of_address.h>
44 #include <linux/of_irq.h>
45 #include <linux/of_platform.h>
46 
47 #include <sound/core.h>
48 #include <sound/pcm.h>
49 #include <sound/pcm_params.h>
50 #include <sound/initval.h>
51 #include <sound/soc.h>
52 #include <sound/dmaengine_pcm.h>
53 
54 #include "fsl_ssi.h"
55 #include "imx-pcm.h"
56 
57 /**
58  * FSLSSI_I2S_RATES: sample rates supported by the I2S
59  *
60  * This driver currently only supports the SSI running in I2S slave mode,
61  * which means the codec determines the sample rate.  Therefore, we tell
62  * ALSA that we support all rates and let the codec driver decide what rates
63  * are really supported.
64  */
65 #define FSLSSI_I2S_RATES SNDRV_PCM_RATE_CONTINUOUS
66 
67 /**
68  * FSLSSI_I2S_FORMATS: audio formats supported by the SSI
69  *
70  * The SSI has a limitation in that the samples must be in the same byte
71  * order as the host CPU.  This is because when multiple bytes are written
72  * to the STX register, the bytes and bits must be written in the same
73  * order.  The STX is a shift register, so all the bits need to be aligned
74  * (bit-endianness must match byte-endianness).  Processors typically write
75  * the bits within a byte in the same order that the bytes of a word are
76  * written in.  So if the host CPU is big-endian, then only big-endian
77  * samples will be written to STX properly.
78  */
79 #ifdef __BIG_ENDIAN
80 #define FSLSSI_I2S_FORMATS (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE | \
81 	 SNDRV_PCM_FMTBIT_S18_3BE | SNDRV_PCM_FMTBIT_S20_3BE | \
82 	 SNDRV_PCM_FMTBIT_S24_3BE | SNDRV_PCM_FMTBIT_S24_BE)
83 #else
84 #define FSLSSI_I2S_FORMATS (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_LE | \
85 	 SNDRV_PCM_FMTBIT_S18_3LE | SNDRV_PCM_FMTBIT_S20_3LE | \
86 	 SNDRV_PCM_FMTBIT_S24_3LE | SNDRV_PCM_FMTBIT_S24_LE)
87 #endif
88 
89 #define FSLSSI_SIER_DBG_RX_FLAGS (CCSR_SSI_SIER_RFF0_EN | \
90 		CCSR_SSI_SIER_RLS_EN | CCSR_SSI_SIER_RFS_EN | \
91 		CCSR_SSI_SIER_ROE0_EN | CCSR_SSI_SIER_RFRC_EN)
92 #define FSLSSI_SIER_DBG_TX_FLAGS (CCSR_SSI_SIER_TFE0_EN | \
93 		CCSR_SSI_SIER_TLS_EN | CCSR_SSI_SIER_TFS_EN | \
94 		CCSR_SSI_SIER_TUE0_EN | CCSR_SSI_SIER_TFRC_EN)
95 
96 enum fsl_ssi_type {
97 	FSL_SSI_MCP8610,
98 	FSL_SSI_MX21,
99 	FSL_SSI_MX35,
100 	FSL_SSI_MX51,
101 };
102 
103 struct fsl_ssi_reg_val {
104 	u32 sier;
105 	u32 srcr;
106 	u32 stcr;
107 	u32 scr;
108 };
109 
110 struct fsl_ssi_rxtx_reg_val {
111 	struct fsl_ssi_reg_val rx;
112 	struct fsl_ssi_reg_val tx;
113 };
114 static const struct regmap_config fsl_ssi_regconfig = {
115 	.max_register = CCSR_SSI_SACCDIS,
116 	.reg_bits = 32,
117 	.val_bits = 32,
118 	.reg_stride = 4,
119 	.val_format_endian = REGMAP_ENDIAN_NATIVE,
120 };
121 
122 struct fsl_ssi_soc_data {
123 	bool imx;
124 	bool offline_config;
125 	u32 sisr_write_mask;
126 };
127 
128 /**
129  * fsl_ssi_private: per-SSI private data
130  *
131  * @reg: Pointer to the regmap registers
132  * @irq: IRQ of this SSI
133  * @cpu_dai_drv: CPU DAI driver for this device
134  *
135  * @dai_fmt: DAI configuration this device is currently used with
136  * @i2s_mode: i2s and network mode configuration of the device. Is used to
137  * switch between normal and i2s/network mode
138  * mode depending on the number of channels
139  * @use_dma: DMA is used or FIQ with stream filter
140  * @use_dual_fifo: DMA with support for both FIFOs used
141  * @fifo_deph: Depth of the SSI FIFOs
142  * @rxtx_reg_val: Specific register settings for receive/transmit configuration
143  *
144  * @clk: SSI clock
145  * @baudclk: SSI baud clock for master mode
146  * @baudclk_streams: Active streams that are using baudclk
147  * @bitclk_freq: bitclock frequency set by .set_dai_sysclk
148  *
149  * @dma_params_tx: DMA transmit parameters
150  * @dma_params_rx: DMA receive parameters
151  * @ssi_phys: physical address of the SSI registers
152  *
153  * @fiq_params: FIQ stream filtering parameters
154  *
155  * @pdev: Pointer to pdev used for deprecated fsl-ssi sound card
156  *
157  * @dbg_stats: Debugging statistics
158  *
159  * @soc: SoC specifc data
160  */
161 struct fsl_ssi_private {
162 	struct regmap *regs;
163 	unsigned int irq;
164 	struct snd_soc_dai_driver cpu_dai_drv;
165 
166 	unsigned int dai_fmt;
167 	u8 i2s_mode;
168 	bool use_dma;
169 	bool use_dual_fifo;
170 	bool has_ipg_clk_name;
171 	unsigned int fifo_depth;
172 	struct fsl_ssi_rxtx_reg_val rxtx_reg_val;
173 
174 	struct clk *clk;
175 	struct clk *baudclk;
176 	unsigned int baudclk_streams;
177 	unsigned int bitclk_freq;
178 
179 	/* DMA params */
180 	struct snd_dmaengine_dai_dma_data dma_params_tx;
181 	struct snd_dmaengine_dai_dma_data dma_params_rx;
182 	dma_addr_t ssi_phys;
183 
184 	/* params for non-dma FIQ stream filtered mode */
185 	struct imx_pcm_fiq_params fiq_params;
186 
187 	/* Used when using fsl-ssi as sound-card. This is only used by ppc and
188 	 * should be replaced with simple-sound-card. */
189 	struct platform_device *pdev;
190 
191 	struct fsl_ssi_dbg dbg_stats;
192 
193 	const struct fsl_ssi_soc_data *soc;
194 };
195 
196 /*
197  * imx51 and later SoCs have a slightly different IP that allows the
198  * SSI configuration while the SSI unit is running.
199  *
200  * More important, it is necessary on those SoCs to configure the
201  * sperate TX/RX DMA bits just before starting the stream
202  * (fsl_ssi_trigger). The SDMA unit has to be configured before fsl_ssi
203  * sends any DMA requests to the SDMA unit, otherwise it is not defined
204  * how the SDMA unit handles the DMA request.
205  *
206  * SDMA units are present on devices starting at imx35 but the imx35
207  * reference manual states that the DMA bits should not be changed
208  * while the SSI unit is running (SSIEN). So we support the necessary
209  * online configuration of fsl-ssi starting at imx51.
210  */
211 
212 static struct fsl_ssi_soc_data fsl_ssi_mpc8610 = {
213 	.imx = false,
214 	.offline_config = true,
215 	.sisr_write_mask = CCSR_SSI_SISR_RFRC | CCSR_SSI_SISR_TFRC |
216 			CCSR_SSI_SISR_ROE0 | CCSR_SSI_SISR_ROE1 |
217 			CCSR_SSI_SISR_TUE0 | CCSR_SSI_SISR_TUE1,
218 };
219 
220 static struct fsl_ssi_soc_data fsl_ssi_imx21 = {
221 	.imx = true,
222 	.offline_config = true,
223 	.sisr_write_mask = 0,
224 };
225 
226 static struct fsl_ssi_soc_data fsl_ssi_imx35 = {
227 	.imx = true,
228 	.offline_config = true,
229 	.sisr_write_mask = CCSR_SSI_SISR_RFRC | CCSR_SSI_SISR_TFRC |
230 			CCSR_SSI_SISR_ROE0 | CCSR_SSI_SISR_ROE1 |
231 			CCSR_SSI_SISR_TUE0 | CCSR_SSI_SISR_TUE1,
232 };
233 
234 static struct fsl_ssi_soc_data fsl_ssi_imx51 = {
235 	.imx = true,
236 	.offline_config = false,
237 	.sisr_write_mask = CCSR_SSI_SISR_ROE0 | CCSR_SSI_SISR_ROE1 |
238 		CCSR_SSI_SISR_TUE0 | CCSR_SSI_SISR_TUE1,
239 };
240 
241 static const struct of_device_id fsl_ssi_ids[] = {
242 	{ .compatible = "fsl,mpc8610-ssi", .data = &fsl_ssi_mpc8610 },
243 	{ .compatible = "fsl,imx51-ssi", .data = &fsl_ssi_imx51 },
244 	{ .compatible = "fsl,imx35-ssi", .data = &fsl_ssi_imx35 },
245 	{ .compatible = "fsl,imx21-ssi", .data = &fsl_ssi_imx21 },
246 	{}
247 };
248 MODULE_DEVICE_TABLE(of, fsl_ssi_ids);
249 
250 static bool fsl_ssi_is_ac97(struct fsl_ssi_private *ssi_private)
251 {
252 	return !!(ssi_private->dai_fmt & SND_SOC_DAIFMT_AC97);
253 }
254 
255 static bool fsl_ssi_is_i2s_master(struct fsl_ssi_private *ssi_private)
256 {
257 	return (ssi_private->dai_fmt & SND_SOC_DAIFMT_MASTER_MASK) ==
258 		SND_SOC_DAIFMT_CBS_CFS;
259 }
260 
261 static bool fsl_ssi_is_i2s_cbm_cfs(struct fsl_ssi_private *ssi_private)
262 {
263 	return (ssi_private->dai_fmt & SND_SOC_DAIFMT_MASTER_MASK) ==
264 		SND_SOC_DAIFMT_CBM_CFS;
265 }
266 /**
267  * fsl_ssi_isr: SSI interrupt handler
268  *
269  * Although it's possible to use the interrupt handler to send and receive
270  * data to/from the SSI, we use the DMA instead.  Programming is more
271  * complicated, but the performance is much better.
272  *
273  * This interrupt handler is used only to gather statistics.
274  *
275  * @irq: IRQ of the SSI device
276  * @dev_id: pointer to the ssi_private structure for this SSI device
277  */
278 static irqreturn_t fsl_ssi_isr(int irq, void *dev_id)
279 {
280 	struct fsl_ssi_private *ssi_private = dev_id;
281 	struct regmap *regs = ssi_private->regs;
282 	__be32 sisr;
283 	__be32 sisr2;
284 
285 	/* We got an interrupt, so read the status register to see what we
286 	   were interrupted for.  We mask it with the Interrupt Enable register
287 	   so that we only check for events that we're interested in.
288 	 */
289 	regmap_read(regs, CCSR_SSI_SISR, &sisr);
290 
291 	sisr2 = sisr & ssi_private->soc->sisr_write_mask;
292 	/* Clear the bits that we set */
293 	if (sisr2)
294 		regmap_write(regs, CCSR_SSI_SISR, sisr2);
295 
296 	fsl_ssi_dbg_isr(&ssi_private->dbg_stats, sisr);
297 
298 	return IRQ_HANDLED;
299 }
300 
301 /*
302  * Enable/Disable all rx/tx config flags at once.
303  */
304 static void fsl_ssi_rxtx_config(struct fsl_ssi_private *ssi_private,
305 		bool enable)
306 {
307 	struct regmap *regs = ssi_private->regs;
308 	struct fsl_ssi_rxtx_reg_val *vals = &ssi_private->rxtx_reg_val;
309 
310 	if (enable) {
311 		regmap_update_bits(regs, CCSR_SSI_SIER,
312 				vals->rx.sier | vals->tx.sier,
313 				vals->rx.sier | vals->tx.sier);
314 		regmap_update_bits(regs, CCSR_SSI_SRCR,
315 				vals->rx.srcr | vals->tx.srcr,
316 				vals->rx.srcr | vals->tx.srcr);
317 		regmap_update_bits(regs, CCSR_SSI_STCR,
318 				vals->rx.stcr | vals->tx.stcr,
319 				vals->rx.stcr | vals->tx.stcr);
320 	} else {
321 		regmap_update_bits(regs, CCSR_SSI_SRCR,
322 				vals->rx.srcr | vals->tx.srcr, 0);
323 		regmap_update_bits(regs, CCSR_SSI_STCR,
324 				vals->rx.stcr | vals->tx.stcr, 0);
325 		regmap_update_bits(regs, CCSR_SSI_SIER,
326 				vals->rx.sier | vals->tx.sier, 0);
327 	}
328 }
329 
330 /*
331  * Calculate the bits that have to be disabled for the current stream that is
332  * getting disabled. This keeps the bits enabled that are necessary for the
333  * second stream to work if 'stream_active' is true.
334  *
335  * Detailed calculation:
336  * These are the values that need to be active after disabling. For non-active
337  * second stream, this is 0:
338  *	vals_stream * !!stream_active
339  *
340  * The following computes the overall differences between the setup for the
341  * to-disable stream and the active stream, a simple XOR:
342  *	vals_disable ^ (vals_stream * !!(stream_active))
343  *
344  * The full expression adds a mask on all values we care about
345  */
346 #define fsl_ssi_disable_val(vals_disable, vals_stream, stream_active) \
347 	((vals_disable) & \
348 	 ((vals_disable) ^ ((vals_stream) * (u32)!!(stream_active))))
349 
350 /*
351  * Enable/Disable a ssi configuration. You have to pass either
352  * ssi_private->rxtx_reg_val.rx or tx as vals parameter.
353  */
354 static void fsl_ssi_config(struct fsl_ssi_private *ssi_private, bool enable,
355 		struct fsl_ssi_reg_val *vals)
356 {
357 	struct regmap *regs = ssi_private->regs;
358 	struct fsl_ssi_reg_val *avals;
359 	int nr_active_streams;
360 	u32 scr_val;
361 	int keep_active;
362 
363 	regmap_read(regs, CCSR_SSI_SCR, &scr_val);
364 
365 	nr_active_streams = !!(scr_val & CCSR_SSI_SCR_TE) +
366 				!!(scr_val & CCSR_SSI_SCR_RE);
367 
368 	if (nr_active_streams - 1 > 0)
369 		keep_active = 1;
370 	else
371 		keep_active = 0;
372 
373 	/* Find the other direction values rx or tx which we do not want to
374 	 * modify */
375 	if (&ssi_private->rxtx_reg_val.rx == vals)
376 		avals = &ssi_private->rxtx_reg_val.tx;
377 	else
378 		avals = &ssi_private->rxtx_reg_val.rx;
379 
380 	/* If vals should be disabled, start with disabling the unit */
381 	if (!enable) {
382 		u32 scr = fsl_ssi_disable_val(vals->scr, avals->scr,
383 				keep_active);
384 		regmap_update_bits(regs, CCSR_SSI_SCR, scr, 0);
385 	}
386 
387 	/*
388 	 * We are running on a SoC which does not support online SSI
389 	 * reconfiguration, so we have to enable all necessary flags at once
390 	 * even if we do not use them later (capture and playback configuration)
391 	 */
392 	if (ssi_private->soc->offline_config) {
393 		if ((enable && !nr_active_streams) ||
394 				(!enable && !keep_active))
395 			fsl_ssi_rxtx_config(ssi_private, enable);
396 
397 		goto config_done;
398 	}
399 
400 	/*
401 	 * Configure single direction units while the SSI unit is running
402 	 * (online configuration)
403 	 */
404 	if (enable) {
405 		regmap_update_bits(regs, CCSR_SSI_SIER, vals->sier, vals->sier);
406 		regmap_update_bits(regs, CCSR_SSI_SRCR, vals->srcr, vals->srcr);
407 		regmap_update_bits(regs, CCSR_SSI_STCR, vals->stcr, vals->stcr);
408 	} else {
409 		u32 sier;
410 		u32 srcr;
411 		u32 stcr;
412 
413 		/*
414 		 * Disabling the necessary flags for one of rx/tx while the
415 		 * other stream is active is a little bit more difficult. We
416 		 * have to disable only those flags that differ between both
417 		 * streams (rx XOR tx) and that are set in the stream that is
418 		 * disabled now. Otherwise we could alter flags of the other
419 		 * stream
420 		 */
421 
422 		/* These assignments are simply vals without bits set in avals*/
423 		sier = fsl_ssi_disable_val(vals->sier, avals->sier,
424 				keep_active);
425 		srcr = fsl_ssi_disable_val(vals->srcr, avals->srcr,
426 				keep_active);
427 		stcr = fsl_ssi_disable_val(vals->stcr, avals->stcr,
428 				keep_active);
429 
430 		regmap_update_bits(regs, CCSR_SSI_SRCR, srcr, 0);
431 		regmap_update_bits(regs, CCSR_SSI_STCR, stcr, 0);
432 		regmap_update_bits(regs, CCSR_SSI_SIER, sier, 0);
433 	}
434 
435 config_done:
436 	/* Enabling of subunits is done after configuration */
437 	if (enable)
438 		regmap_update_bits(regs, CCSR_SSI_SCR, vals->scr, vals->scr);
439 }
440 
441 
442 static void fsl_ssi_rx_config(struct fsl_ssi_private *ssi_private, bool enable)
443 {
444 	fsl_ssi_config(ssi_private, enable, &ssi_private->rxtx_reg_val.rx);
445 }
446 
447 static void fsl_ssi_tx_config(struct fsl_ssi_private *ssi_private, bool enable)
448 {
449 	fsl_ssi_config(ssi_private, enable, &ssi_private->rxtx_reg_val.tx);
450 }
451 
452 /*
453  * Setup rx/tx register values used to enable/disable the streams. These will
454  * be used later in fsl_ssi_config to setup the streams without the need to
455  * check for all different SSI modes.
456  */
457 static void fsl_ssi_setup_reg_vals(struct fsl_ssi_private *ssi_private)
458 {
459 	struct fsl_ssi_rxtx_reg_val *reg = &ssi_private->rxtx_reg_val;
460 
461 	reg->rx.sier = CCSR_SSI_SIER_RFF0_EN;
462 	reg->rx.srcr = CCSR_SSI_SRCR_RFEN0;
463 	reg->rx.scr = 0;
464 	reg->tx.sier = CCSR_SSI_SIER_TFE0_EN;
465 	reg->tx.stcr = CCSR_SSI_STCR_TFEN0;
466 	reg->tx.scr = 0;
467 
468 	if (!fsl_ssi_is_ac97(ssi_private)) {
469 		reg->rx.scr = CCSR_SSI_SCR_SSIEN | CCSR_SSI_SCR_RE;
470 		reg->rx.sier |= CCSR_SSI_SIER_RFF0_EN;
471 		reg->tx.scr = CCSR_SSI_SCR_SSIEN | CCSR_SSI_SCR_TE;
472 		reg->tx.sier |= CCSR_SSI_SIER_TFE0_EN;
473 	}
474 
475 	if (ssi_private->use_dma) {
476 		reg->rx.sier |= CCSR_SSI_SIER_RDMAE;
477 		reg->tx.sier |= CCSR_SSI_SIER_TDMAE;
478 	} else {
479 		reg->rx.sier |= CCSR_SSI_SIER_RIE;
480 		reg->tx.sier |= CCSR_SSI_SIER_TIE;
481 	}
482 
483 	reg->rx.sier |= FSLSSI_SIER_DBG_RX_FLAGS;
484 	reg->tx.sier |= FSLSSI_SIER_DBG_TX_FLAGS;
485 }
486 
487 static void fsl_ssi_setup_ac97(struct fsl_ssi_private *ssi_private)
488 {
489 	struct regmap *regs = ssi_private->regs;
490 
491 	/*
492 	 * Setup the clock control register
493 	 */
494 	regmap_write(regs, CCSR_SSI_STCCR,
495 			CCSR_SSI_SxCCR_WL(17) | CCSR_SSI_SxCCR_DC(13));
496 	regmap_write(regs, CCSR_SSI_SRCCR,
497 			CCSR_SSI_SxCCR_WL(17) | CCSR_SSI_SxCCR_DC(13));
498 
499 	/*
500 	 * Enable AC97 mode and startup the SSI
501 	 */
502 	regmap_write(regs, CCSR_SSI_SACNT,
503 			CCSR_SSI_SACNT_AC97EN | CCSR_SSI_SACNT_FV);
504 	regmap_write(regs, CCSR_SSI_SACCDIS, 0xff);
505 	regmap_write(regs, CCSR_SSI_SACCEN, 0x300);
506 
507 	/*
508 	 * Enable SSI, Transmit and Receive. AC97 has to communicate with the
509 	 * codec before a stream is started.
510 	 */
511 	regmap_update_bits(regs, CCSR_SSI_SCR,
512 			CCSR_SSI_SCR_SSIEN | CCSR_SSI_SCR_TE | CCSR_SSI_SCR_RE,
513 			CCSR_SSI_SCR_SSIEN | CCSR_SSI_SCR_TE | CCSR_SSI_SCR_RE);
514 
515 	regmap_write(regs, CCSR_SSI_SOR, CCSR_SSI_SOR_WAIT(3));
516 }
517 
518 /**
519  * fsl_ssi_startup: create a new substream
520  *
521  * This is the first function called when a stream is opened.
522  *
523  * If this is the first stream open, then grab the IRQ and program most of
524  * the SSI registers.
525  */
526 static int fsl_ssi_startup(struct snd_pcm_substream *substream,
527 			   struct snd_soc_dai *dai)
528 {
529 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
530 	struct fsl_ssi_private *ssi_private =
531 		snd_soc_dai_get_drvdata(rtd->cpu_dai);
532 	int ret;
533 
534 	ret = clk_prepare_enable(ssi_private->clk);
535 	if (ret)
536 		return ret;
537 
538 	/* When using dual fifo mode, it is safer to ensure an even period
539 	 * size. If appearing to an odd number while DMA always starts its
540 	 * task from fifo0, fifo1 would be neglected at the end of each
541 	 * period. But SSI would still access fifo1 with an invalid data.
542 	 */
543 	if (ssi_private->use_dual_fifo)
544 		snd_pcm_hw_constraint_step(substream->runtime, 0,
545 				SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 2);
546 
547 	return 0;
548 }
549 
550 /**
551  * fsl_ssi_shutdown: shutdown the SSI
552  *
553  */
554 static void fsl_ssi_shutdown(struct snd_pcm_substream *substream,
555 				struct snd_soc_dai *dai)
556 {
557 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
558 	struct fsl_ssi_private *ssi_private =
559 		snd_soc_dai_get_drvdata(rtd->cpu_dai);
560 
561 	clk_disable_unprepare(ssi_private->clk);
562 
563 }
564 
565 /**
566  * fsl_ssi_set_bclk - configure Digital Audio Interface bit clock
567  *
568  * Note: This function can be only called when using SSI as DAI master
569  *
570  * Quick instruction for parameters:
571  * freq: Output BCLK frequency = samplerate * 32 (fixed) * channels
572  * dir: SND_SOC_CLOCK_OUT -> TxBCLK, SND_SOC_CLOCK_IN -> RxBCLK.
573  */
574 static int fsl_ssi_set_bclk(struct snd_pcm_substream *substream,
575 		struct snd_soc_dai *cpu_dai,
576 		struct snd_pcm_hw_params *hw_params)
577 {
578 	struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(cpu_dai);
579 	struct regmap *regs = ssi_private->regs;
580 	int synchronous = ssi_private->cpu_dai_drv.symmetric_rates, ret;
581 	u32 pm = 999, div2, psr, stccr, mask, afreq, factor, i;
582 	unsigned long clkrate, baudrate, tmprate;
583 	u64 sub, savesub = 100000;
584 	unsigned int freq;
585 	bool baudclk_is_used;
586 
587 	/* Prefer the explicitly set bitclock frequency */
588 	if (ssi_private->bitclk_freq)
589 		freq = ssi_private->bitclk_freq;
590 	else
591 		freq = params_channels(hw_params) * 32 * params_rate(hw_params);
592 
593 	/* Don't apply it to any non-baudclk circumstance */
594 	if (IS_ERR(ssi_private->baudclk))
595 		return -EINVAL;
596 
597 	baudclk_is_used = ssi_private->baudclk_streams & ~(BIT(substream->stream));
598 
599 	/* It should be already enough to divide clock by setting pm alone */
600 	psr = 0;
601 	div2 = 0;
602 
603 	factor = (div2 + 1) * (7 * psr + 1) * 2;
604 
605 	for (i = 0; i < 255; i++) {
606 		/* The bclk rate must be smaller than 1/5 sysclk rate */
607 		if (factor * (i + 1) < 5)
608 			continue;
609 
610 		tmprate = freq * factor * (i + 2);
611 
612 		if (baudclk_is_used)
613 			clkrate = clk_get_rate(ssi_private->baudclk);
614 		else
615 			clkrate = clk_round_rate(ssi_private->baudclk, tmprate);
616 
617 		clkrate /= factor;
618 		afreq = clkrate / (i + 1);
619 
620 		if (freq == afreq)
621 			sub = 0;
622 		else if (freq / afreq == 1)
623 			sub = freq - afreq;
624 		else if (afreq / freq == 1)
625 			sub = afreq - freq;
626 		else
627 			continue;
628 
629 		/* Calculate the fraction */
630 		sub *= 100000;
631 		do_div(sub, freq);
632 
633 		if (sub < savesub) {
634 			baudrate = tmprate;
635 			savesub = sub;
636 			pm = i;
637 		}
638 
639 		/* We are lucky */
640 		if (savesub == 0)
641 			break;
642 	}
643 
644 	/* No proper pm found if it is still remaining the initial value */
645 	if (pm == 999) {
646 		dev_err(cpu_dai->dev, "failed to handle the required sysclk\n");
647 		return -EINVAL;
648 	}
649 
650 	stccr = CCSR_SSI_SxCCR_PM(pm + 1) | (div2 ? CCSR_SSI_SxCCR_DIV2 : 0) |
651 		(psr ? CCSR_SSI_SxCCR_PSR : 0);
652 	mask = CCSR_SSI_SxCCR_PM_MASK | CCSR_SSI_SxCCR_DIV2 |
653 		CCSR_SSI_SxCCR_PSR;
654 
655 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK || synchronous)
656 		regmap_update_bits(regs, CCSR_SSI_STCCR, mask, stccr);
657 	else
658 		regmap_update_bits(regs, CCSR_SSI_SRCCR, mask, stccr);
659 
660 	if (!baudclk_is_used) {
661 		ret = clk_set_rate(ssi_private->baudclk, baudrate);
662 		if (ret) {
663 			dev_err(cpu_dai->dev, "failed to set baudclk rate\n");
664 			return -EINVAL;
665 		}
666 	}
667 
668 	return 0;
669 }
670 
671 static int fsl_ssi_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
672 		int clk_id, unsigned int freq, int dir)
673 {
674 	struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(cpu_dai);
675 
676 	ssi_private->bitclk_freq = freq;
677 
678 	return 0;
679 }
680 
681 /**
682  * fsl_ssi_hw_params - program the sample size
683  *
684  * Most of the SSI registers have been programmed in the startup function,
685  * but the word length must be programmed here.  Unfortunately, programming
686  * the SxCCR.WL bits requires the SSI to be temporarily disabled.  This can
687  * cause a problem with supporting simultaneous playback and capture.  If
688  * the SSI is already playing a stream, then that stream may be temporarily
689  * stopped when you start capture.
690  *
691  * Note: The SxCCR.DC and SxCCR.PM bits are only used if the SSI is the
692  * clock master.
693  */
694 static int fsl_ssi_hw_params(struct snd_pcm_substream *substream,
695 	struct snd_pcm_hw_params *hw_params, struct snd_soc_dai *cpu_dai)
696 {
697 	struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(cpu_dai);
698 	struct regmap *regs = ssi_private->regs;
699 	unsigned int channels = params_channels(hw_params);
700 	unsigned int sample_size =
701 		snd_pcm_format_width(params_format(hw_params));
702 	u32 wl = CCSR_SSI_SxCCR_WL(sample_size);
703 	int ret;
704 	u32 scr_val;
705 	int enabled;
706 
707 	regmap_read(regs, CCSR_SSI_SCR, &scr_val);
708 	enabled = scr_val & CCSR_SSI_SCR_SSIEN;
709 
710 	/*
711 	 * If we're in synchronous mode, and the SSI is already enabled,
712 	 * then STCCR is already set properly.
713 	 */
714 	if (enabled && ssi_private->cpu_dai_drv.symmetric_rates)
715 		return 0;
716 
717 	if (fsl_ssi_is_i2s_master(ssi_private)) {
718 		ret = fsl_ssi_set_bclk(substream, cpu_dai, hw_params);
719 		if (ret)
720 			return ret;
721 
722 		/* Do not enable the clock if it is already enabled */
723 		if (!(ssi_private->baudclk_streams & BIT(substream->stream))) {
724 			ret = clk_prepare_enable(ssi_private->baudclk);
725 			if (ret)
726 				return ret;
727 
728 			ssi_private->baudclk_streams |= BIT(substream->stream);
729 		}
730 	}
731 
732 	if (!fsl_ssi_is_ac97(ssi_private)) {
733 		u8 i2smode;
734 		/*
735 		 * Switch to normal net mode in order to have a frame sync
736 		 * signal every 32 bits instead of 16 bits
737 		 */
738 		if (fsl_ssi_is_i2s_cbm_cfs(ssi_private) && sample_size == 16)
739 			i2smode = CCSR_SSI_SCR_I2S_MODE_NORMAL |
740 				CCSR_SSI_SCR_NET;
741 		else
742 			i2smode = ssi_private->i2s_mode;
743 
744 		regmap_update_bits(regs, CCSR_SSI_SCR,
745 				CCSR_SSI_SCR_NET | CCSR_SSI_SCR_I2S_MODE_MASK,
746 				channels == 1 ? 0 : i2smode);
747 	}
748 
749 	/*
750 	 * FIXME: The documentation says that SxCCR[WL] should not be
751 	 * modified while the SSI is enabled.  The only time this can
752 	 * happen is if we're trying to do simultaneous playback and
753 	 * capture in asynchronous mode.  Unfortunately, I have been enable
754 	 * to get that to work at all on the P1022DS.  Therefore, we don't
755 	 * bother to disable/enable the SSI when setting SxCCR[WL], because
756 	 * the SSI will stop anyway.  Maybe one day, this will get fixed.
757 	 */
758 
759 	/* In synchronous mode, the SSI uses STCCR for capture */
760 	if ((substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ||
761 	    ssi_private->cpu_dai_drv.symmetric_rates)
762 		regmap_update_bits(regs, CCSR_SSI_STCCR, CCSR_SSI_SxCCR_WL_MASK,
763 				wl);
764 	else
765 		regmap_update_bits(regs, CCSR_SSI_SRCCR, CCSR_SSI_SxCCR_WL_MASK,
766 				wl);
767 
768 	return 0;
769 }
770 
771 static int fsl_ssi_hw_free(struct snd_pcm_substream *substream,
772 		struct snd_soc_dai *cpu_dai)
773 {
774 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
775 	struct fsl_ssi_private *ssi_private =
776 		snd_soc_dai_get_drvdata(rtd->cpu_dai);
777 
778 	if (fsl_ssi_is_i2s_master(ssi_private) &&
779 			ssi_private->baudclk_streams & BIT(substream->stream)) {
780 		clk_disable_unprepare(ssi_private->baudclk);
781 		ssi_private->baudclk_streams &= ~BIT(substream->stream);
782 	}
783 
784 	return 0;
785 }
786 
787 static int _fsl_ssi_set_dai_fmt(struct device *dev,
788 				struct fsl_ssi_private *ssi_private,
789 				unsigned int fmt)
790 {
791 	struct regmap *regs = ssi_private->regs;
792 	u32 strcr = 0, stcr, srcr, scr, mask;
793 	u8 wm;
794 
795 	ssi_private->dai_fmt = fmt;
796 
797 	if (fsl_ssi_is_i2s_master(ssi_private) && IS_ERR(ssi_private->baudclk)) {
798 		dev_err(dev, "baudclk is missing which is necessary for master mode\n");
799 		return -EINVAL;
800 	}
801 
802 	fsl_ssi_setup_reg_vals(ssi_private);
803 
804 	regmap_read(regs, CCSR_SSI_SCR, &scr);
805 	scr &= ~(CCSR_SSI_SCR_SYN | CCSR_SSI_SCR_I2S_MODE_MASK);
806 	scr |= CCSR_SSI_SCR_SYNC_TX_FS;
807 
808 	mask = CCSR_SSI_STCR_TXBIT0 | CCSR_SSI_STCR_TFDIR | CCSR_SSI_STCR_TXDIR |
809 		CCSR_SSI_STCR_TSCKP | CCSR_SSI_STCR_TFSI | CCSR_SSI_STCR_TFSL |
810 		CCSR_SSI_STCR_TEFS;
811 	regmap_read(regs, CCSR_SSI_STCR, &stcr);
812 	regmap_read(regs, CCSR_SSI_SRCR, &srcr);
813 	stcr &= ~mask;
814 	srcr &= ~mask;
815 
816 	ssi_private->i2s_mode = CCSR_SSI_SCR_NET;
817 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
818 	case SND_SOC_DAIFMT_I2S:
819 		switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
820 		case SND_SOC_DAIFMT_CBM_CFS:
821 		case SND_SOC_DAIFMT_CBS_CFS:
822 			ssi_private->i2s_mode |= CCSR_SSI_SCR_I2S_MODE_MASTER;
823 			regmap_update_bits(regs, CCSR_SSI_STCCR,
824 					CCSR_SSI_SxCCR_DC_MASK,
825 					CCSR_SSI_SxCCR_DC(2));
826 			regmap_update_bits(regs, CCSR_SSI_SRCCR,
827 					CCSR_SSI_SxCCR_DC_MASK,
828 					CCSR_SSI_SxCCR_DC(2));
829 			break;
830 		case SND_SOC_DAIFMT_CBM_CFM:
831 			ssi_private->i2s_mode |= CCSR_SSI_SCR_I2S_MODE_SLAVE;
832 			break;
833 		default:
834 			return -EINVAL;
835 		}
836 
837 		/* Data on rising edge of bclk, frame low, 1clk before data */
838 		strcr |= CCSR_SSI_STCR_TFSI | CCSR_SSI_STCR_TSCKP |
839 			CCSR_SSI_STCR_TXBIT0 | CCSR_SSI_STCR_TEFS;
840 		break;
841 	case SND_SOC_DAIFMT_LEFT_J:
842 		/* Data on rising edge of bclk, frame high */
843 		strcr |= CCSR_SSI_STCR_TXBIT0 | CCSR_SSI_STCR_TSCKP;
844 		break;
845 	case SND_SOC_DAIFMT_DSP_A:
846 		/* Data on rising edge of bclk, frame high, 1clk before data */
847 		strcr |= CCSR_SSI_STCR_TFSL | CCSR_SSI_STCR_TSCKP |
848 			CCSR_SSI_STCR_TXBIT0 | CCSR_SSI_STCR_TEFS;
849 		break;
850 	case SND_SOC_DAIFMT_DSP_B:
851 		/* Data on rising edge of bclk, frame high */
852 		strcr |= CCSR_SSI_STCR_TFSL | CCSR_SSI_STCR_TSCKP |
853 			CCSR_SSI_STCR_TXBIT0;
854 		break;
855 	case SND_SOC_DAIFMT_AC97:
856 		ssi_private->i2s_mode |= CCSR_SSI_SCR_I2S_MODE_NORMAL;
857 		break;
858 	default:
859 		return -EINVAL;
860 	}
861 	scr |= ssi_private->i2s_mode;
862 
863 	/* DAI clock inversion */
864 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
865 	case SND_SOC_DAIFMT_NB_NF:
866 		/* Nothing to do for both normal cases */
867 		break;
868 	case SND_SOC_DAIFMT_IB_NF:
869 		/* Invert bit clock */
870 		strcr ^= CCSR_SSI_STCR_TSCKP;
871 		break;
872 	case SND_SOC_DAIFMT_NB_IF:
873 		/* Invert frame clock */
874 		strcr ^= CCSR_SSI_STCR_TFSI;
875 		break;
876 	case SND_SOC_DAIFMT_IB_IF:
877 		/* Invert both clocks */
878 		strcr ^= CCSR_SSI_STCR_TSCKP;
879 		strcr ^= CCSR_SSI_STCR_TFSI;
880 		break;
881 	default:
882 		return -EINVAL;
883 	}
884 
885 	/* DAI clock master masks */
886 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
887 	case SND_SOC_DAIFMT_CBS_CFS:
888 		strcr |= CCSR_SSI_STCR_TFDIR | CCSR_SSI_STCR_TXDIR;
889 		scr |= CCSR_SSI_SCR_SYS_CLK_EN;
890 		break;
891 	case SND_SOC_DAIFMT_CBM_CFM:
892 		scr &= ~CCSR_SSI_SCR_SYS_CLK_EN;
893 		break;
894 	case SND_SOC_DAIFMT_CBM_CFS:
895 		strcr &= ~CCSR_SSI_STCR_TXDIR;
896 		strcr |= CCSR_SSI_STCR_TFDIR;
897 		scr &= ~CCSR_SSI_SCR_SYS_CLK_EN;
898 		break;
899 	default:
900 		return -EINVAL;
901 	}
902 
903 	stcr |= strcr;
904 	srcr |= strcr;
905 
906 	if (ssi_private->cpu_dai_drv.symmetric_rates) {
907 		/* Need to clear RXDIR when using SYNC mode */
908 		srcr &= ~CCSR_SSI_SRCR_RXDIR;
909 		scr |= CCSR_SSI_SCR_SYN;
910 	}
911 
912 	regmap_write(regs, CCSR_SSI_STCR, stcr);
913 	regmap_write(regs, CCSR_SSI_SRCR, srcr);
914 	regmap_write(regs, CCSR_SSI_SCR, scr);
915 
916 	/*
917 	 * Set the watermark for transmit FIFI 0 and receive FIFO 0. We don't
918 	 * use FIFO 1. We program the transmit water to signal a DMA transfer
919 	 * if there are only two (or fewer) elements left in the FIFO. Two
920 	 * elements equals one frame (left channel, right channel). This value,
921 	 * however, depends on the depth of the transmit buffer.
922 	 *
923 	 * We set the watermark on the same level as the DMA burstsize.  For
924 	 * fiq it is probably better to use the biggest possible watermark
925 	 * size.
926 	 */
927 	if (ssi_private->use_dma)
928 		wm = ssi_private->fifo_depth - 2;
929 	else
930 		wm = ssi_private->fifo_depth;
931 
932 	regmap_write(regs, CCSR_SSI_SFCSR,
933 			CCSR_SSI_SFCSR_TFWM0(wm) | CCSR_SSI_SFCSR_RFWM0(wm) |
934 			CCSR_SSI_SFCSR_TFWM1(wm) | CCSR_SSI_SFCSR_RFWM1(wm));
935 
936 	if (ssi_private->use_dual_fifo) {
937 		regmap_update_bits(regs, CCSR_SSI_SRCR, CCSR_SSI_SRCR_RFEN1,
938 				CCSR_SSI_SRCR_RFEN1);
939 		regmap_update_bits(regs, CCSR_SSI_STCR, CCSR_SSI_STCR_TFEN1,
940 				CCSR_SSI_STCR_TFEN1);
941 		regmap_update_bits(regs, CCSR_SSI_SCR, CCSR_SSI_SCR_TCH_EN,
942 				CCSR_SSI_SCR_TCH_EN);
943 	}
944 
945 	if (fmt & SND_SOC_DAIFMT_AC97)
946 		fsl_ssi_setup_ac97(ssi_private);
947 
948 	return 0;
949 
950 }
951 
952 /**
953  * fsl_ssi_set_dai_fmt - configure Digital Audio Interface Format.
954  */
955 static int fsl_ssi_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
956 {
957 	struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(cpu_dai);
958 
959 	return _fsl_ssi_set_dai_fmt(cpu_dai->dev, ssi_private, fmt);
960 }
961 
962 /**
963  * fsl_ssi_set_dai_tdm_slot - set TDM slot number
964  *
965  * Note: This function can be only called when using SSI as DAI master
966  */
967 static int fsl_ssi_set_dai_tdm_slot(struct snd_soc_dai *cpu_dai, u32 tx_mask,
968 				u32 rx_mask, int slots, int slot_width)
969 {
970 	struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(cpu_dai);
971 	struct regmap *regs = ssi_private->regs;
972 	u32 val;
973 
974 	/* The slot number should be >= 2 if using Network mode or I2S mode */
975 	regmap_read(regs, CCSR_SSI_SCR, &val);
976 	val &= CCSR_SSI_SCR_I2S_MODE_MASK | CCSR_SSI_SCR_NET;
977 	if (val && slots < 2) {
978 		dev_err(cpu_dai->dev, "slot number should be >= 2 in I2S or NET\n");
979 		return -EINVAL;
980 	}
981 
982 	regmap_update_bits(regs, CCSR_SSI_STCCR, CCSR_SSI_SxCCR_DC_MASK,
983 			CCSR_SSI_SxCCR_DC(slots));
984 	regmap_update_bits(regs, CCSR_SSI_SRCCR, CCSR_SSI_SxCCR_DC_MASK,
985 			CCSR_SSI_SxCCR_DC(slots));
986 
987 	/* The register SxMSKs needs SSI to provide essential clock due to
988 	 * hardware design. So we here temporarily enable SSI to set them.
989 	 */
990 	regmap_read(regs, CCSR_SSI_SCR, &val);
991 	val &= CCSR_SSI_SCR_SSIEN;
992 	regmap_update_bits(regs, CCSR_SSI_SCR, CCSR_SSI_SCR_SSIEN,
993 			CCSR_SSI_SCR_SSIEN);
994 
995 	regmap_write(regs, CCSR_SSI_STMSK, tx_mask);
996 	regmap_write(regs, CCSR_SSI_SRMSK, rx_mask);
997 
998 	regmap_update_bits(regs, CCSR_SSI_SCR, CCSR_SSI_SCR_SSIEN, val);
999 
1000 	return 0;
1001 }
1002 
1003 /**
1004  * fsl_ssi_trigger: start and stop the DMA transfer.
1005  *
1006  * This function is called by ALSA to start, stop, pause, and resume the DMA
1007  * transfer of data.
1008  *
1009  * The DMA channel is in external master start and pause mode, which
1010  * means the SSI completely controls the flow of data.
1011  */
1012 static int fsl_ssi_trigger(struct snd_pcm_substream *substream, int cmd,
1013 			   struct snd_soc_dai *dai)
1014 {
1015 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
1016 	struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(rtd->cpu_dai);
1017 	struct regmap *regs = ssi_private->regs;
1018 
1019 	switch (cmd) {
1020 	case SNDRV_PCM_TRIGGER_START:
1021 	case SNDRV_PCM_TRIGGER_RESUME:
1022 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1023 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
1024 			fsl_ssi_tx_config(ssi_private, true);
1025 		else
1026 			fsl_ssi_rx_config(ssi_private, true);
1027 		break;
1028 
1029 	case SNDRV_PCM_TRIGGER_STOP:
1030 	case SNDRV_PCM_TRIGGER_SUSPEND:
1031 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1032 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
1033 			fsl_ssi_tx_config(ssi_private, false);
1034 		else
1035 			fsl_ssi_rx_config(ssi_private, false);
1036 		break;
1037 
1038 	default:
1039 		return -EINVAL;
1040 	}
1041 
1042 	if (fsl_ssi_is_ac97(ssi_private)) {
1043 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
1044 			regmap_write(regs, CCSR_SSI_SOR, CCSR_SSI_SOR_TX_CLR);
1045 		else
1046 			regmap_write(regs, CCSR_SSI_SOR, CCSR_SSI_SOR_RX_CLR);
1047 	}
1048 
1049 	return 0;
1050 }
1051 
1052 static int fsl_ssi_dai_probe(struct snd_soc_dai *dai)
1053 {
1054 	struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(dai);
1055 
1056 	if (ssi_private->soc->imx && ssi_private->use_dma) {
1057 		dai->playback_dma_data = &ssi_private->dma_params_tx;
1058 		dai->capture_dma_data = &ssi_private->dma_params_rx;
1059 	}
1060 
1061 	return 0;
1062 }
1063 
1064 static const struct snd_soc_dai_ops fsl_ssi_dai_ops = {
1065 	.startup	= fsl_ssi_startup,
1066 	.shutdown       = fsl_ssi_shutdown,
1067 	.hw_params	= fsl_ssi_hw_params,
1068 	.hw_free	= fsl_ssi_hw_free,
1069 	.set_fmt	= fsl_ssi_set_dai_fmt,
1070 	.set_sysclk	= fsl_ssi_set_dai_sysclk,
1071 	.set_tdm_slot	= fsl_ssi_set_dai_tdm_slot,
1072 	.trigger	= fsl_ssi_trigger,
1073 };
1074 
1075 /* Template for the CPU dai driver structure */
1076 static struct snd_soc_dai_driver fsl_ssi_dai_template = {
1077 	.probe = fsl_ssi_dai_probe,
1078 	.playback = {
1079 		.stream_name = "CPU-Playback",
1080 		.channels_min = 1,
1081 		.channels_max = 2,
1082 		.rates = FSLSSI_I2S_RATES,
1083 		.formats = FSLSSI_I2S_FORMATS,
1084 	},
1085 	.capture = {
1086 		.stream_name = "CPU-Capture",
1087 		.channels_min = 1,
1088 		.channels_max = 2,
1089 		.rates = FSLSSI_I2S_RATES,
1090 		.formats = FSLSSI_I2S_FORMATS,
1091 	},
1092 	.ops = &fsl_ssi_dai_ops,
1093 };
1094 
1095 static const struct snd_soc_component_driver fsl_ssi_component = {
1096 	.name		= "fsl-ssi",
1097 };
1098 
1099 static struct snd_soc_dai_driver fsl_ssi_ac97_dai = {
1100 	.bus_control = true,
1101 	.playback = {
1102 		.stream_name = "AC97 Playback",
1103 		.channels_min = 2,
1104 		.channels_max = 2,
1105 		.rates = SNDRV_PCM_RATE_8000_48000,
1106 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
1107 	},
1108 	.capture = {
1109 		.stream_name = "AC97 Capture",
1110 		.channels_min = 2,
1111 		.channels_max = 2,
1112 		.rates = SNDRV_PCM_RATE_48000,
1113 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
1114 	},
1115 	.ops = &fsl_ssi_dai_ops,
1116 };
1117 
1118 
1119 static struct fsl_ssi_private *fsl_ac97_data;
1120 
1121 static void fsl_ssi_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
1122 		unsigned short val)
1123 {
1124 	struct regmap *regs = fsl_ac97_data->regs;
1125 	unsigned int lreg;
1126 	unsigned int lval;
1127 
1128 	if (reg > 0x7f)
1129 		return;
1130 
1131 
1132 	lreg = reg <<  12;
1133 	regmap_write(regs, CCSR_SSI_SACADD, lreg);
1134 
1135 	lval = val << 4;
1136 	regmap_write(regs, CCSR_SSI_SACDAT, lval);
1137 
1138 	regmap_update_bits(regs, CCSR_SSI_SACNT, CCSR_SSI_SACNT_RDWR_MASK,
1139 			CCSR_SSI_SACNT_WR);
1140 	udelay(100);
1141 }
1142 
1143 static unsigned short fsl_ssi_ac97_read(struct snd_ac97 *ac97,
1144 		unsigned short reg)
1145 {
1146 	struct regmap *regs = fsl_ac97_data->regs;
1147 
1148 	unsigned short val = -1;
1149 	u32 reg_val;
1150 	unsigned int lreg;
1151 
1152 	lreg = (reg & 0x7f) <<  12;
1153 	regmap_write(regs, CCSR_SSI_SACADD, lreg);
1154 	regmap_update_bits(regs, CCSR_SSI_SACNT, CCSR_SSI_SACNT_RDWR_MASK,
1155 			CCSR_SSI_SACNT_RD);
1156 
1157 	udelay(100);
1158 
1159 	regmap_read(regs, CCSR_SSI_SACDAT, &reg_val);
1160 	val = (reg_val >> 4) & 0xffff;
1161 
1162 	return val;
1163 }
1164 
1165 static struct snd_ac97_bus_ops fsl_ssi_ac97_ops = {
1166 	.read		= fsl_ssi_ac97_read,
1167 	.write		= fsl_ssi_ac97_write,
1168 };
1169 
1170 /**
1171  * Make every character in a string lower-case
1172  */
1173 static void make_lowercase(char *s)
1174 {
1175 	char *p = s;
1176 	char c;
1177 
1178 	while ((c = *p)) {
1179 		if ((c >= 'A') && (c <= 'Z'))
1180 			*p = c + ('a' - 'A');
1181 		p++;
1182 	}
1183 }
1184 
1185 static int fsl_ssi_imx_probe(struct platform_device *pdev,
1186 		struct fsl_ssi_private *ssi_private, void __iomem *iomem)
1187 {
1188 	struct device_node *np = pdev->dev.of_node;
1189 	u32 dmas[4];
1190 	int ret;
1191 
1192 	if (ssi_private->has_ipg_clk_name)
1193 		ssi_private->clk = devm_clk_get(&pdev->dev, "ipg");
1194 	else
1195 		ssi_private->clk = devm_clk_get(&pdev->dev, NULL);
1196 	if (IS_ERR(ssi_private->clk)) {
1197 		ret = PTR_ERR(ssi_private->clk);
1198 		dev_err(&pdev->dev, "could not get clock: %d\n", ret);
1199 		return ret;
1200 	}
1201 
1202 	if (!ssi_private->has_ipg_clk_name) {
1203 		ret = clk_prepare_enable(ssi_private->clk);
1204 		if (ret) {
1205 			dev_err(&pdev->dev, "clk_prepare_enable failed: %d\n", ret);
1206 			return ret;
1207 		}
1208 	}
1209 
1210 	/* For those SLAVE implementations, we ingore non-baudclk cases
1211 	 * and, instead, abandon MASTER mode that needs baud clock.
1212 	 */
1213 	ssi_private->baudclk = devm_clk_get(&pdev->dev, "baud");
1214 	if (IS_ERR(ssi_private->baudclk))
1215 		dev_dbg(&pdev->dev, "could not get baud clock: %ld\n",
1216 			 PTR_ERR(ssi_private->baudclk));
1217 
1218 	/*
1219 	 * We have burstsize be "fifo_depth - 2" to match the SSI
1220 	 * watermark setting in fsl_ssi_startup().
1221 	 */
1222 	ssi_private->dma_params_tx.maxburst = ssi_private->fifo_depth - 2;
1223 	ssi_private->dma_params_rx.maxburst = ssi_private->fifo_depth - 2;
1224 	ssi_private->dma_params_tx.addr = ssi_private->ssi_phys + CCSR_SSI_STX0;
1225 	ssi_private->dma_params_rx.addr = ssi_private->ssi_phys + CCSR_SSI_SRX0;
1226 
1227 	ret = !of_property_read_u32_array(np, "dmas", dmas, 4);
1228 	if (ssi_private->use_dma && !ret && dmas[2] == IMX_DMATYPE_SSI_DUAL) {
1229 		ssi_private->use_dual_fifo = true;
1230 		/* When using dual fifo mode, we need to keep watermark
1231 		 * as even numbers due to dma script limitation.
1232 		 */
1233 		ssi_private->dma_params_tx.maxburst &= ~0x1;
1234 		ssi_private->dma_params_rx.maxburst &= ~0x1;
1235 	}
1236 
1237 	if (!ssi_private->use_dma) {
1238 
1239 		/*
1240 		 * Some boards use an incompatible codec. To get it
1241 		 * working, we are using imx-fiq-pcm-audio, that
1242 		 * can handle those codecs. DMA is not possible in this
1243 		 * situation.
1244 		 */
1245 
1246 		ssi_private->fiq_params.irq = ssi_private->irq;
1247 		ssi_private->fiq_params.base = iomem;
1248 		ssi_private->fiq_params.dma_params_rx =
1249 			&ssi_private->dma_params_rx;
1250 		ssi_private->fiq_params.dma_params_tx =
1251 			&ssi_private->dma_params_tx;
1252 
1253 		ret = imx_pcm_fiq_init(pdev, &ssi_private->fiq_params);
1254 		if (ret)
1255 			goto error_pcm;
1256 	} else {
1257 		ret = imx_pcm_dma_init(pdev);
1258 		if (ret)
1259 			goto error_pcm;
1260 	}
1261 
1262 	return 0;
1263 
1264 error_pcm:
1265 
1266 	if (!ssi_private->has_ipg_clk_name)
1267 		clk_disable_unprepare(ssi_private->clk);
1268 	return ret;
1269 }
1270 
1271 static void fsl_ssi_imx_clean(struct platform_device *pdev,
1272 		struct fsl_ssi_private *ssi_private)
1273 {
1274 	if (!ssi_private->use_dma)
1275 		imx_pcm_fiq_exit(pdev);
1276 	if (!ssi_private->has_ipg_clk_name)
1277 		clk_disable_unprepare(ssi_private->clk);
1278 }
1279 
1280 static int fsl_ssi_probe(struct platform_device *pdev)
1281 {
1282 	struct fsl_ssi_private *ssi_private;
1283 	int ret = 0;
1284 	struct device_node *np = pdev->dev.of_node;
1285 	const struct of_device_id *of_id;
1286 	const char *p, *sprop;
1287 	const uint32_t *iprop;
1288 	struct resource res;
1289 	void __iomem *iomem;
1290 	char name[64];
1291 
1292 	/* SSIs that are not connected on the board should have a
1293 	 *      status = "disabled"
1294 	 * property in their device tree nodes.
1295 	 */
1296 	if (!of_device_is_available(np))
1297 		return -ENODEV;
1298 
1299 	of_id = of_match_device(fsl_ssi_ids, &pdev->dev);
1300 	if (!of_id || !of_id->data)
1301 		return -EINVAL;
1302 
1303 	ssi_private = devm_kzalloc(&pdev->dev, sizeof(*ssi_private),
1304 			GFP_KERNEL);
1305 	if (!ssi_private) {
1306 		dev_err(&pdev->dev, "could not allocate DAI object\n");
1307 		return -ENOMEM;
1308 	}
1309 
1310 	ssi_private->soc = of_id->data;
1311 
1312 	sprop = of_get_property(np, "fsl,mode", NULL);
1313 	if (sprop) {
1314 		if (!strcmp(sprop, "ac97-slave"))
1315 			ssi_private->dai_fmt = SND_SOC_DAIFMT_AC97;
1316 	}
1317 
1318 	ssi_private->use_dma = !of_property_read_bool(np,
1319 			"fsl,fiq-stream-filter");
1320 
1321 	if (fsl_ssi_is_ac97(ssi_private)) {
1322 		memcpy(&ssi_private->cpu_dai_drv, &fsl_ssi_ac97_dai,
1323 				sizeof(fsl_ssi_ac97_dai));
1324 
1325 		fsl_ac97_data = ssi_private;
1326 
1327 		snd_soc_set_ac97_ops_of_reset(&fsl_ssi_ac97_ops, pdev);
1328 	} else {
1329 		/* Initialize this copy of the CPU DAI driver structure */
1330 		memcpy(&ssi_private->cpu_dai_drv, &fsl_ssi_dai_template,
1331 		       sizeof(fsl_ssi_dai_template));
1332 	}
1333 	ssi_private->cpu_dai_drv.name = dev_name(&pdev->dev);
1334 
1335 	/* Get the addresses and IRQ */
1336 	ret = of_address_to_resource(np, 0, &res);
1337 	if (ret) {
1338 		dev_err(&pdev->dev, "could not determine device resources\n");
1339 		return ret;
1340 	}
1341 	ssi_private->ssi_phys = res.start;
1342 
1343 	iomem = devm_ioremap(&pdev->dev, res.start, resource_size(&res));
1344 	if (!iomem) {
1345 		dev_err(&pdev->dev, "could not map device resources\n");
1346 		return -ENOMEM;
1347 	}
1348 
1349 	ret = of_property_match_string(np, "clock-names", "ipg");
1350 	if (ret < 0) {
1351 		ssi_private->has_ipg_clk_name = false;
1352 		ssi_private->regs = devm_regmap_init_mmio(&pdev->dev, iomem,
1353 			&fsl_ssi_regconfig);
1354 	} else {
1355 		ssi_private->has_ipg_clk_name = true;
1356 		ssi_private->regs = devm_regmap_init_mmio_clk(&pdev->dev,
1357 			"ipg", iomem, &fsl_ssi_regconfig);
1358 	}
1359 	if (IS_ERR(ssi_private->regs)) {
1360 		dev_err(&pdev->dev, "Failed to init register map\n");
1361 		return PTR_ERR(ssi_private->regs);
1362 	}
1363 
1364 	ssi_private->irq = platform_get_irq(pdev, 0);
1365 	if (!ssi_private->irq) {
1366 		dev_err(&pdev->dev, "no irq for node %s\n", np->full_name);
1367 		return -ENXIO;
1368 	}
1369 
1370 	/* Are the RX and the TX clocks locked? */
1371 	if (!of_find_property(np, "fsl,ssi-asynchronous", NULL)) {
1372 		ssi_private->cpu_dai_drv.symmetric_rates = 1;
1373 		ssi_private->cpu_dai_drv.symmetric_channels = 1;
1374 		ssi_private->cpu_dai_drv.symmetric_samplebits = 1;
1375 	}
1376 
1377 	/* Determine the FIFO depth. */
1378 	iprop = of_get_property(np, "fsl,fifo-depth", NULL);
1379 	if (iprop)
1380 		ssi_private->fifo_depth = be32_to_cpup(iprop);
1381 	else
1382                 /* Older 8610 DTs didn't have the fifo-depth property */
1383 		ssi_private->fifo_depth = 8;
1384 
1385 	dev_set_drvdata(&pdev->dev, ssi_private);
1386 
1387 	if (ssi_private->soc->imx) {
1388 		ret = fsl_ssi_imx_probe(pdev, ssi_private, iomem);
1389 		if (ret)
1390 			return ret;
1391 	}
1392 
1393 	ret = snd_soc_register_component(&pdev->dev, &fsl_ssi_component,
1394 					 &ssi_private->cpu_dai_drv, 1);
1395 	if (ret) {
1396 		dev_err(&pdev->dev, "failed to register DAI: %d\n", ret);
1397 		goto error_asoc_register;
1398 	}
1399 
1400 	if (ssi_private->use_dma) {
1401 		ret = devm_request_irq(&pdev->dev, ssi_private->irq,
1402 					fsl_ssi_isr, 0, dev_name(&pdev->dev),
1403 					ssi_private);
1404 		if (ret < 0) {
1405 			dev_err(&pdev->dev, "could not claim irq %u\n",
1406 					ssi_private->irq);
1407 			goto error_irq;
1408 		}
1409 	}
1410 
1411 	ret = fsl_ssi_debugfs_create(&ssi_private->dbg_stats, &pdev->dev);
1412 	if (ret)
1413 		goto error_irq;
1414 
1415 	/*
1416 	 * If codec-handle property is missing from SSI node, we assume
1417 	 * that the machine driver uses new binding which does not require
1418 	 * SSI driver to trigger machine driver's probe.
1419 	 */
1420 	if (!of_get_property(np, "codec-handle", NULL))
1421 		goto done;
1422 
1423 	/* Trigger the machine driver's probe function.  The platform driver
1424 	 * name of the machine driver is taken from /compatible property of the
1425 	 * device tree.  We also pass the address of the CPU DAI driver
1426 	 * structure.
1427 	 */
1428 	sprop = of_get_property(of_find_node_by_path("/"), "compatible", NULL);
1429 	/* Sometimes the compatible name has a "fsl," prefix, so we strip it. */
1430 	p = strrchr(sprop, ',');
1431 	if (p)
1432 		sprop = p + 1;
1433 	snprintf(name, sizeof(name), "snd-soc-%s", sprop);
1434 	make_lowercase(name);
1435 
1436 	ssi_private->pdev =
1437 		platform_device_register_data(&pdev->dev, name, 0, NULL, 0);
1438 	if (IS_ERR(ssi_private->pdev)) {
1439 		ret = PTR_ERR(ssi_private->pdev);
1440 		dev_err(&pdev->dev, "failed to register platform: %d\n", ret);
1441 		goto error_sound_card;
1442 	}
1443 
1444 done:
1445 	if (ssi_private->dai_fmt)
1446 		_fsl_ssi_set_dai_fmt(&pdev->dev, ssi_private,
1447 				     ssi_private->dai_fmt);
1448 
1449 	return 0;
1450 
1451 error_sound_card:
1452 	fsl_ssi_debugfs_remove(&ssi_private->dbg_stats);
1453 
1454 error_irq:
1455 	snd_soc_unregister_component(&pdev->dev);
1456 
1457 error_asoc_register:
1458 	if (ssi_private->soc->imx)
1459 		fsl_ssi_imx_clean(pdev, ssi_private);
1460 
1461 	return ret;
1462 }
1463 
1464 static int fsl_ssi_remove(struct platform_device *pdev)
1465 {
1466 	struct fsl_ssi_private *ssi_private = dev_get_drvdata(&pdev->dev);
1467 
1468 	fsl_ssi_debugfs_remove(&ssi_private->dbg_stats);
1469 
1470 	if (ssi_private->pdev)
1471 		platform_device_unregister(ssi_private->pdev);
1472 	snd_soc_unregister_component(&pdev->dev);
1473 
1474 	if (ssi_private->soc->imx)
1475 		fsl_ssi_imx_clean(pdev, ssi_private);
1476 
1477 	return 0;
1478 }
1479 
1480 static struct platform_driver fsl_ssi_driver = {
1481 	.driver = {
1482 		.name = "fsl-ssi-dai",
1483 		.of_match_table = fsl_ssi_ids,
1484 	},
1485 	.probe = fsl_ssi_probe,
1486 	.remove = fsl_ssi_remove,
1487 };
1488 
1489 module_platform_driver(fsl_ssi_driver);
1490 
1491 MODULE_ALIAS("platform:fsl-ssi-dai");
1492 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
1493 MODULE_DESCRIPTION("Freescale Synchronous Serial Interface (SSI) ASoC Driver");
1494 MODULE_LICENSE("GPL v2");
1495