xref: /openbmc/linux/sound/soc/fsl/fsl_ssi.c (revision 92b19ff5)
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 	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 		tmprate = freq * factor * (i + 1);
607 
608 		if (baudclk_is_used)
609 			clkrate = clk_get_rate(ssi_private->baudclk);
610 		else
611 			clkrate = clk_round_rate(ssi_private->baudclk, tmprate);
612 
613 		/*
614 		 * Hardware limitation: The bclk rate must be
615 		 * never greater than 1/5 IPG clock rate
616 		 */
617 		if (clkrate * 5 > clk_get_rate(ssi_private->clk))
618 			continue;
619 
620 		clkrate /= factor;
621 		afreq = clkrate / (i + 1);
622 
623 		if (freq == afreq)
624 			sub = 0;
625 		else if (freq / afreq == 1)
626 			sub = freq - afreq;
627 		else if (afreq / freq == 1)
628 			sub = afreq - freq;
629 		else
630 			continue;
631 
632 		/* Calculate the fraction */
633 		sub *= 100000;
634 		do_div(sub, freq);
635 
636 		if (sub < savesub) {
637 			baudrate = tmprate;
638 			savesub = sub;
639 			pm = i;
640 		}
641 
642 		/* We are lucky */
643 		if (savesub == 0)
644 			break;
645 	}
646 
647 	/* No proper pm found if it is still remaining the initial value */
648 	if (pm == 999) {
649 		dev_err(cpu_dai->dev, "failed to handle the required sysclk\n");
650 		return -EINVAL;
651 	}
652 
653 	stccr = CCSR_SSI_SxCCR_PM(pm + 1) | (div2 ? CCSR_SSI_SxCCR_DIV2 : 0) |
654 		(psr ? CCSR_SSI_SxCCR_PSR : 0);
655 	mask = CCSR_SSI_SxCCR_PM_MASK | CCSR_SSI_SxCCR_DIV2 |
656 		CCSR_SSI_SxCCR_PSR;
657 
658 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK || synchronous)
659 		regmap_update_bits(regs, CCSR_SSI_STCCR, mask, stccr);
660 	else
661 		regmap_update_bits(regs, CCSR_SSI_SRCCR, mask, stccr);
662 
663 	if (!baudclk_is_used) {
664 		ret = clk_set_rate(ssi_private->baudclk, baudrate);
665 		if (ret) {
666 			dev_err(cpu_dai->dev, "failed to set baudclk rate\n");
667 			return -EINVAL;
668 		}
669 	}
670 
671 	return 0;
672 }
673 
674 static int fsl_ssi_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
675 		int clk_id, unsigned int freq, int dir)
676 {
677 	struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(cpu_dai);
678 
679 	ssi_private->bitclk_freq = freq;
680 
681 	return 0;
682 }
683 
684 /**
685  * fsl_ssi_hw_params - program the sample size
686  *
687  * Most of the SSI registers have been programmed in the startup function,
688  * but the word length must be programmed here.  Unfortunately, programming
689  * the SxCCR.WL bits requires the SSI to be temporarily disabled.  This can
690  * cause a problem with supporting simultaneous playback and capture.  If
691  * the SSI is already playing a stream, then that stream may be temporarily
692  * stopped when you start capture.
693  *
694  * Note: The SxCCR.DC and SxCCR.PM bits are only used if the SSI is the
695  * clock master.
696  */
697 static int fsl_ssi_hw_params(struct snd_pcm_substream *substream,
698 	struct snd_pcm_hw_params *hw_params, struct snd_soc_dai *cpu_dai)
699 {
700 	struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(cpu_dai);
701 	struct regmap *regs = ssi_private->regs;
702 	unsigned int channels = params_channels(hw_params);
703 	unsigned int sample_size =
704 		snd_pcm_format_width(params_format(hw_params));
705 	u32 wl = CCSR_SSI_SxCCR_WL(sample_size);
706 	int ret;
707 	u32 scr_val;
708 	int enabled;
709 
710 	regmap_read(regs, CCSR_SSI_SCR, &scr_val);
711 	enabled = scr_val & CCSR_SSI_SCR_SSIEN;
712 
713 	/*
714 	 * If we're in synchronous mode, and the SSI is already enabled,
715 	 * then STCCR is already set properly.
716 	 */
717 	if (enabled && ssi_private->cpu_dai_drv.symmetric_rates)
718 		return 0;
719 
720 	if (fsl_ssi_is_i2s_master(ssi_private)) {
721 		ret = fsl_ssi_set_bclk(substream, cpu_dai, hw_params);
722 		if (ret)
723 			return ret;
724 
725 		/* Do not enable the clock if it is already enabled */
726 		if (!(ssi_private->baudclk_streams & BIT(substream->stream))) {
727 			ret = clk_prepare_enable(ssi_private->baudclk);
728 			if (ret)
729 				return ret;
730 
731 			ssi_private->baudclk_streams |= BIT(substream->stream);
732 		}
733 	}
734 
735 	if (!fsl_ssi_is_ac97(ssi_private)) {
736 		u8 i2smode;
737 		/*
738 		 * Switch to normal net mode in order to have a frame sync
739 		 * signal every 32 bits instead of 16 bits
740 		 */
741 		if (fsl_ssi_is_i2s_cbm_cfs(ssi_private) && sample_size == 16)
742 			i2smode = CCSR_SSI_SCR_I2S_MODE_NORMAL |
743 				CCSR_SSI_SCR_NET;
744 		else
745 			i2smode = ssi_private->i2s_mode;
746 
747 		regmap_update_bits(regs, CCSR_SSI_SCR,
748 				CCSR_SSI_SCR_NET | CCSR_SSI_SCR_I2S_MODE_MASK,
749 				channels == 1 ? 0 : i2smode);
750 	}
751 
752 	/*
753 	 * FIXME: The documentation says that SxCCR[WL] should not be
754 	 * modified while the SSI is enabled.  The only time this can
755 	 * happen is if we're trying to do simultaneous playback and
756 	 * capture in asynchronous mode.  Unfortunately, I have been enable
757 	 * to get that to work at all on the P1022DS.  Therefore, we don't
758 	 * bother to disable/enable the SSI when setting SxCCR[WL], because
759 	 * the SSI will stop anyway.  Maybe one day, this will get fixed.
760 	 */
761 
762 	/* In synchronous mode, the SSI uses STCCR for capture */
763 	if ((substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ||
764 	    ssi_private->cpu_dai_drv.symmetric_rates)
765 		regmap_update_bits(regs, CCSR_SSI_STCCR, CCSR_SSI_SxCCR_WL_MASK,
766 				wl);
767 	else
768 		regmap_update_bits(regs, CCSR_SSI_SRCCR, CCSR_SSI_SxCCR_WL_MASK,
769 				wl);
770 
771 	return 0;
772 }
773 
774 static int fsl_ssi_hw_free(struct snd_pcm_substream *substream,
775 		struct snd_soc_dai *cpu_dai)
776 {
777 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
778 	struct fsl_ssi_private *ssi_private =
779 		snd_soc_dai_get_drvdata(rtd->cpu_dai);
780 
781 	if (fsl_ssi_is_i2s_master(ssi_private) &&
782 			ssi_private->baudclk_streams & BIT(substream->stream)) {
783 		clk_disable_unprepare(ssi_private->baudclk);
784 		ssi_private->baudclk_streams &= ~BIT(substream->stream);
785 	}
786 
787 	return 0;
788 }
789 
790 static int _fsl_ssi_set_dai_fmt(struct device *dev,
791 				struct fsl_ssi_private *ssi_private,
792 				unsigned int fmt)
793 {
794 	struct regmap *regs = ssi_private->regs;
795 	u32 strcr = 0, stcr, srcr, scr, mask;
796 	u8 wm;
797 
798 	ssi_private->dai_fmt = fmt;
799 
800 	if (fsl_ssi_is_i2s_master(ssi_private) && IS_ERR(ssi_private->baudclk)) {
801 		dev_err(dev, "baudclk is missing which is necessary for master mode\n");
802 		return -EINVAL;
803 	}
804 
805 	fsl_ssi_setup_reg_vals(ssi_private);
806 
807 	regmap_read(regs, CCSR_SSI_SCR, &scr);
808 	scr &= ~(CCSR_SSI_SCR_SYN | CCSR_SSI_SCR_I2S_MODE_MASK);
809 	scr |= CCSR_SSI_SCR_SYNC_TX_FS;
810 
811 	mask = CCSR_SSI_STCR_TXBIT0 | CCSR_SSI_STCR_TFDIR | CCSR_SSI_STCR_TXDIR |
812 		CCSR_SSI_STCR_TSCKP | CCSR_SSI_STCR_TFSI | CCSR_SSI_STCR_TFSL |
813 		CCSR_SSI_STCR_TEFS;
814 	regmap_read(regs, CCSR_SSI_STCR, &stcr);
815 	regmap_read(regs, CCSR_SSI_SRCR, &srcr);
816 	stcr &= ~mask;
817 	srcr &= ~mask;
818 
819 	ssi_private->i2s_mode = CCSR_SSI_SCR_NET;
820 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
821 	case SND_SOC_DAIFMT_I2S:
822 		switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
823 		case SND_SOC_DAIFMT_CBM_CFS:
824 		case SND_SOC_DAIFMT_CBS_CFS:
825 			ssi_private->i2s_mode |= CCSR_SSI_SCR_I2S_MODE_MASTER;
826 			regmap_update_bits(regs, CCSR_SSI_STCCR,
827 					CCSR_SSI_SxCCR_DC_MASK,
828 					CCSR_SSI_SxCCR_DC(2));
829 			regmap_update_bits(regs, CCSR_SSI_SRCCR,
830 					CCSR_SSI_SxCCR_DC_MASK,
831 					CCSR_SSI_SxCCR_DC(2));
832 			break;
833 		case SND_SOC_DAIFMT_CBM_CFM:
834 			ssi_private->i2s_mode |= CCSR_SSI_SCR_I2S_MODE_SLAVE;
835 			break;
836 		default:
837 			return -EINVAL;
838 		}
839 
840 		/* Data on rising edge of bclk, frame low, 1clk before data */
841 		strcr |= CCSR_SSI_STCR_TFSI | CCSR_SSI_STCR_TSCKP |
842 			CCSR_SSI_STCR_TXBIT0 | CCSR_SSI_STCR_TEFS;
843 		break;
844 	case SND_SOC_DAIFMT_LEFT_J:
845 		/* Data on rising edge of bclk, frame high */
846 		strcr |= CCSR_SSI_STCR_TXBIT0 | CCSR_SSI_STCR_TSCKP;
847 		break;
848 	case SND_SOC_DAIFMT_DSP_A:
849 		/* Data on rising edge of bclk, frame high, 1clk before data */
850 		strcr |= CCSR_SSI_STCR_TFSL | CCSR_SSI_STCR_TSCKP |
851 			CCSR_SSI_STCR_TXBIT0 | CCSR_SSI_STCR_TEFS;
852 		break;
853 	case SND_SOC_DAIFMT_DSP_B:
854 		/* Data on rising edge of bclk, frame high */
855 		strcr |= CCSR_SSI_STCR_TFSL | CCSR_SSI_STCR_TSCKP |
856 			CCSR_SSI_STCR_TXBIT0;
857 		break;
858 	case SND_SOC_DAIFMT_AC97:
859 		ssi_private->i2s_mode |= CCSR_SSI_SCR_I2S_MODE_NORMAL;
860 		break;
861 	default:
862 		return -EINVAL;
863 	}
864 	scr |= ssi_private->i2s_mode;
865 
866 	/* DAI clock inversion */
867 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
868 	case SND_SOC_DAIFMT_NB_NF:
869 		/* Nothing to do for both normal cases */
870 		break;
871 	case SND_SOC_DAIFMT_IB_NF:
872 		/* Invert bit clock */
873 		strcr ^= CCSR_SSI_STCR_TSCKP;
874 		break;
875 	case SND_SOC_DAIFMT_NB_IF:
876 		/* Invert frame clock */
877 		strcr ^= CCSR_SSI_STCR_TFSI;
878 		break;
879 	case SND_SOC_DAIFMT_IB_IF:
880 		/* Invert both clocks */
881 		strcr ^= CCSR_SSI_STCR_TSCKP;
882 		strcr ^= CCSR_SSI_STCR_TFSI;
883 		break;
884 	default:
885 		return -EINVAL;
886 	}
887 
888 	/* DAI clock master masks */
889 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
890 	case SND_SOC_DAIFMT_CBS_CFS:
891 		strcr |= CCSR_SSI_STCR_TFDIR | CCSR_SSI_STCR_TXDIR;
892 		scr |= CCSR_SSI_SCR_SYS_CLK_EN;
893 		break;
894 	case SND_SOC_DAIFMT_CBM_CFM:
895 		scr &= ~CCSR_SSI_SCR_SYS_CLK_EN;
896 		break;
897 	case SND_SOC_DAIFMT_CBM_CFS:
898 		strcr &= ~CCSR_SSI_STCR_TXDIR;
899 		strcr |= CCSR_SSI_STCR_TFDIR;
900 		scr &= ~CCSR_SSI_SCR_SYS_CLK_EN;
901 		break;
902 	default:
903 		return -EINVAL;
904 	}
905 
906 	stcr |= strcr;
907 	srcr |= strcr;
908 
909 	if (ssi_private->cpu_dai_drv.symmetric_rates) {
910 		/* Need to clear RXDIR when using SYNC mode */
911 		srcr &= ~CCSR_SSI_SRCR_RXDIR;
912 		scr |= CCSR_SSI_SCR_SYN;
913 	}
914 
915 	regmap_write(regs, CCSR_SSI_STCR, stcr);
916 	regmap_write(regs, CCSR_SSI_SRCR, srcr);
917 	regmap_write(regs, CCSR_SSI_SCR, scr);
918 
919 	/*
920 	 * Set the watermark for transmit FIFI 0 and receive FIFO 0. We don't
921 	 * use FIFO 1. We program the transmit water to signal a DMA transfer
922 	 * if there are only two (or fewer) elements left in the FIFO. Two
923 	 * elements equals one frame (left channel, right channel). This value,
924 	 * however, depends on the depth of the transmit buffer.
925 	 *
926 	 * We set the watermark on the same level as the DMA burstsize.  For
927 	 * fiq it is probably better to use the biggest possible watermark
928 	 * size.
929 	 */
930 	if (ssi_private->use_dma)
931 		wm = ssi_private->fifo_depth - 2;
932 	else
933 		wm = ssi_private->fifo_depth;
934 
935 	regmap_write(regs, CCSR_SSI_SFCSR,
936 			CCSR_SSI_SFCSR_TFWM0(wm) | CCSR_SSI_SFCSR_RFWM0(wm) |
937 			CCSR_SSI_SFCSR_TFWM1(wm) | CCSR_SSI_SFCSR_RFWM1(wm));
938 
939 	if (ssi_private->use_dual_fifo) {
940 		regmap_update_bits(regs, CCSR_SSI_SRCR, CCSR_SSI_SRCR_RFEN1,
941 				CCSR_SSI_SRCR_RFEN1);
942 		regmap_update_bits(regs, CCSR_SSI_STCR, CCSR_SSI_STCR_TFEN1,
943 				CCSR_SSI_STCR_TFEN1);
944 		regmap_update_bits(regs, CCSR_SSI_SCR, CCSR_SSI_SCR_TCH_EN,
945 				CCSR_SSI_SCR_TCH_EN);
946 	}
947 
948 	if (fmt & SND_SOC_DAIFMT_AC97)
949 		fsl_ssi_setup_ac97(ssi_private);
950 
951 	return 0;
952 
953 }
954 
955 /**
956  * fsl_ssi_set_dai_fmt - configure Digital Audio Interface Format.
957  */
958 static int fsl_ssi_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
959 {
960 	struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(cpu_dai);
961 
962 	return _fsl_ssi_set_dai_fmt(cpu_dai->dev, ssi_private, fmt);
963 }
964 
965 /**
966  * fsl_ssi_set_dai_tdm_slot - set TDM slot number
967  *
968  * Note: This function can be only called when using SSI as DAI master
969  */
970 static int fsl_ssi_set_dai_tdm_slot(struct snd_soc_dai *cpu_dai, u32 tx_mask,
971 				u32 rx_mask, int slots, int slot_width)
972 {
973 	struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(cpu_dai);
974 	struct regmap *regs = ssi_private->regs;
975 	u32 val;
976 
977 	/* The slot number should be >= 2 if using Network mode or I2S mode */
978 	regmap_read(regs, CCSR_SSI_SCR, &val);
979 	val &= CCSR_SSI_SCR_I2S_MODE_MASK | CCSR_SSI_SCR_NET;
980 	if (val && slots < 2) {
981 		dev_err(cpu_dai->dev, "slot number should be >= 2 in I2S or NET\n");
982 		return -EINVAL;
983 	}
984 
985 	regmap_update_bits(regs, CCSR_SSI_STCCR, CCSR_SSI_SxCCR_DC_MASK,
986 			CCSR_SSI_SxCCR_DC(slots));
987 	regmap_update_bits(regs, CCSR_SSI_SRCCR, CCSR_SSI_SxCCR_DC_MASK,
988 			CCSR_SSI_SxCCR_DC(slots));
989 
990 	/* The register SxMSKs needs SSI to provide essential clock due to
991 	 * hardware design. So we here temporarily enable SSI to set them.
992 	 */
993 	regmap_read(regs, CCSR_SSI_SCR, &val);
994 	val &= CCSR_SSI_SCR_SSIEN;
995 	regmap_update_bits(regs, CCSR_SSI_SCR, CCSR_SSI_SCR_SSIEN,
996 			CCSR_SSI_SCR_SSIEN);
997 
998 	regmap_write(regs, CCSR_SSI_STMSK, ~tx_mask);
999 	regmap_write(regs, CCSR_SSI_SRMSK, ~rx_mask);
1000 
1001 	regmap_update_bits(regs, CCSR_SSI_SCR, CCSR_SSI_SCR_SSIEN, val);
1002 
1003 	return 0;
1004 }
1005 
1006 /**
1007  * fsl_ssi_trigger: start and stop the DMA transfer.
1008  *
1009  * This function is called by ALSA to start, stop, pause, and resume the DMA
1010  * transfer of data.
1011  *
1012  * The DMA channel is in external master start and pause mode, which
1013  * means the SSI completely controls the flow of data.
1014  */
1015 static int fsl_ssi_trigger(struct snd_pcm_substream *substream, int cmd,
1016 			   struct snd_soc_dai *dai)
1017 {
1018 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
1019 	struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(rtd->cpu_dai);
1020 	struct regmap *regs = ssi_private->regs;
1021 
1022 	switch (cmd) {
1023 	case SNDRV_PCM_TRIGGER_START:
1024 	case SNDRV_PCM_TRIGGER_RESUME:
1025 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1026 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
1027 			fsl_ssi_tx_config(ssi_private, true);
1028 		else
1029 			fsl_ssi_rx_config(ssi_private, true);
1030 		break;
1031 
1032 	case SNDRV_PCM_TRIGGER_STOP:
1033 	case SNDRV_PCM_TRIGGER_SUSPEND:
1034 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1035 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
1036 			fsl_ssi_tx_config(ssi_private, false);
1037 		else
1038 			fsl_ssi_rx_config(ssi_private, false);
1039 		break;
1040 
1041 	default:
1042 		return -EINVAL;
1043 	}
1044 
1045 	if (fsl_ssi_is_ac97(ssi_private)) {
1046 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
1047 			regmap_write(regs, CCSR_SSI_SOR, CCSR_SSI_SOR_TX_CLR);
1048 		else
1049 			regmap_write(regs, CCSR_SSI_SOR, CCSR_SSI_SOR_RX_CLR);
1050 	}
1051 
1052 	return 0;
1053 }
1054 
1055 static int fsl_ssi_dai_probe(struct snd_soc_dai *dai)
1056 {
1057 	struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(dai);
1058 
1059 	if (ssi_private->soc->imx && ssi_private->use_dma) {
1060 		dai->playback_dma_data = &ssi_private->dma_params_tx;
1061 		dai->capture_dma_data = &ssi_private->dma_params_rx;
1062 	}
1063 
1064 	return 0;
1065 }
1066 
1067 static const struct snd_soc_dai_ops fsl_ssi_dai_ops = {
1068 	.startup	= fsl_ssi_startup,
1069 	.shutdown       = fsl_ssi_shutdown,
1070 	.hw_params	= fsl_ssi_hw_params,
1071 	.hw_free	= fsl_ssi_hw_free,
1072 	.set_fmt	= fsl_ssi_set_dai_fmt,
1073 	.set_sysclk	= fsl_ssi_set_dai_sysclk,
1074 	.set_tdm_slot	= fsl_ssi_set_dai_tdm_slot,
1075 	.trigger	= fsl_ssi_trigger,
1076 };
1077 
1078 /* Template for the CPU dai driver structure */
1079 static struct snd_soc_dai_driver fsl_ssi_dai_template = {
1080 	.probe = fsl_ssi_dai_probe,
1081 	.playback = {
1082 		.stream_name = "CPU-Playback",
1083 		.channels_min = 1,
1084 		.channels_max = 2,
1085 		.rates = FSLSSI_I2S_RATES,
1086 		.formats = FSLSSI_I2S_FORMATS,
1087 	},
1088 	.capture = {
1089 		.stream_name = "CPU-Capture",
1090 		.channels_min = 1,
1091 		.channels_max = 2,
1092 		.rates = FSLSSI_I2S_RATES,
1093 		.formats = FSLSSI_I2S_FORMATS,
1094 	},
1095 	.ops = &fsl_ssi_dai_ops,
1096 };
1097 
1098 static const struct snd_soc_component_driver fsl_ssi_component = {
1099 	.name		= "fsl-ssi",
1100 };
1101 
1102 static struct snd_soc_dai_driver fsl_ssi_ac97_dai = {
1103 	.bus_control = true,
1104 	.playback = {
1105 		.stream_name = "AC97 Playback",
1106 		.channels_min = 2,
1107 		.channels_max = 2,
1108 		.rates = SNDRV_PCM_RATE_8000_48000,
1109 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
1110 	},
1111 	.capture = {
1112 		.stream_name = "AC97 Capture",
1113 		.channels_min = 2,
1114 		.channels_max = 2,
1115 		.rates = SNDRV_PCM_RATE_48000,
1116 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
1117 	},
1118 	.ops = &fsl_ssi_dai_ops,
1119 };
1120 
1121 
1122 static struct fsl_ssi_private *fsl_ac97_data;
1123 
1124 static void fsl_ssi_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
1125 		unsigned short val)
1126 {
1127 	struct regmap *regs = fsl_ac97_data->regs;
1128 	unsigned int lreg;
1129 	unsigned int lval;
1130 
1131 	if (reg > 0x7f)
1132 		return;
1133 
1134 
1135 	lreg = reg <<  12;
1136 	regmap_write(regs, CCSR_SSI_SACADD, lreg);
1137 
1138 	lval = val << 4;
1139 	regmap_write(regs, CCSR_SSI_SACDAT, lval);
1140 
1141 	regmap_update_bits(regs, CCSR_SSI_SACNT, CCSR_SSI_SACNT_RDWR_MASK,
1142 			CCSR_SSI_SACNT_WR);
1143 	udelay(100);
1144 }
1145 
1146 static unsigned short fsl_ssi_ac97_read(struct snd_ac97 *ac97,
1147 		unsigned short reg)
1148 {
1149 	struct regmap *regs = fsl_ac97_data->regs;
1150 
1151 	unsigned short val = -1;
1152 	u32 reg_val;
1153 	unsigned int lreg;
1154 
1155 	lreg = (reg & 0x7f) <<  12;
1156 	regmap_write(regs, CCSR_SSI_SACADD, lreg);
1157 	regmap_update_bits(regs, CCSR_SSI_SACNT, CCSR_SSI_SACNT_RDWR_MASK,
1158 			CCSR_SSI_SACNT_RD);
1159 
1160 	udelay(100);
1161 
1162 	regmap_read(regs, CCSR_SSI_SACDAT, &reg_val);
1163 	val = (reg_val >> 4) & 0xffff;
1164 
1165 	return val;
1166 }
1167 
1168 static struct snd_ac97_bus_ops fsl_ssi_ac97_ops = {
1169 	.read		= fsl_ssi_ac97_read,
1170 	.write		= fsl_ssi_ac97_write,
1171 };
1172 
1173 /**
1174  * Make every character in a string lower-case
1175  */
1176 static void make_lowercase(char *s)
1177 {
1178 	char *p = s;
1179 	char c;
1180 
1181 	while ((c = *p)) {
1182 		if ((c >= 'A') && (c <= 'Z'))
1183 			*p = c + ('a' - 'A');
1184 		p++;
1185 	}
1186 }
1187 
1188 static int fsl_ssi_imx_probe(struct platform_device *pdev,
1189 		struct fsl_ssi_private *ssi_private, void __iomem *iomem)
1190 {
1191 	struct device_node *np = pdev->dev.of_node;
1192 	u32 dmas[4];
1193 	int ret;
1194 
1195 	if (ssi_private->has_ipg_clk_name)
1196 		ssi_private->clk = devm_clk_get(&pdev->dev, "ipg");
1197 	else
1198 		ssi_private->clk = devm_clk_get(&pdev->dev, NULL);
1199 	if (IS_ERR(ssi_private->clk)) {
1200 		ret = PTR_ERR(ssi_private->clk);
1201 		dev_err(&pdev->dev, "could not get clock: %d\n", ret);
1202 		return ret;
1203 	}
1204 
1205 	if (!ssi_private->has_ipg_clk_name) {
1206 		ret = clk_prepare_enable(ssi_private->clk);
1207 		if (ret) {
1208 			dev_err(&pdev->dev, "clk_prepare_enable failed: %d\n", ret);
1209 			return ret;
1210 		}
1211 	}
1212 
1213 	/* For those SLAVE implementations, we ingore non-baudclk cases
1214 	 * and, instead, abandon MASTER mode that needs baud clock.
1215 	 */
1216 	ssi_private->baudclk = devm_clk_get(&pdev->dev, "baud");
1217 	if (IS_ERR(ssi_private->baudclk))
1218 		dev_dbg(&pdev->dev, "could not get baud clock: %ld\n",
1219 			 PTR_ERR(ssi_private->baudclk));
1220 
1221 	/*
1222 	 * We have burstsize be "fifo_depth - 2" to match the SSI
1223 	 * watermark setting in fsl_ssi_startup().
1224 	 */
1225 	ssi_private->dma_params_tx.maxburst = ssi_private->fifo_depth - 2;
1226 	ssi_private->dma_params_rx.maxburst = ssi_private->fifo_depth - 2;
1227 	ssi_private->dma_params_tx.addr = ssi_private->ssi_phys + CCSR_SSI_STX0;
1228 	ssi_private->dma_params_rx.addr = ssi_private->ssi_phys + CCSR_SSI_SRX0;
1229 
1230 	ret = of_property_read_u32_array(np, "dmas", dmas, 4);
1231 	if (ssi_private->use_dma && !ret && dmas[2] == IMX_DMATYPE_SSI_DUAL) {
1232 		ssi_private->use_dual_fifo = true;
1233 		/* When using dual fifo mode, we need to keep watermark
1234 		 * as even numbers due to dma script limitation.
1235 		 */
1236 		ssi_private->dma_params_tx.maxburst &= ~0x1;
1237 		ssi_private->dma_params_rx.maxburst &= ~0x1;
1238 	}
1239 
1240 	if (!ssi_private->use_dma) {
1241 
1242 		/*
1243 		 * Some boards use an incompatible codec. To get it
1244 		 * working, we are using imx-fiq-pcm-audio, that
1245 		 * can handle those codecs. DMA is not possible in this
1246 		 * situation.
1247 		 */
1248 
1249 		ssi_private->fiq_params.irq = ssi_private->irq;
1250 		ssi_private->fiq_params.base = iomem;
1251 		ssi_private->fiq_params.dma_params_rx =
1252 			&ssi_private->dma_params_rx;
1253 		ssi_private->fiq_params.dma_params_tx =
1254 			&ssi_private->dma_params_tx;
1255 
1256 		ret = imx_pcm_fiq_init(pdev, &ssi_private->fiq_params);
1257 		if (ret)
1258 			goto error_pcm;
1259 	} else {
1260 		ret = imx_pcm_dma_init(pdev);
1261 		if (ret)
1262 			goto error_pcm;
1263 	}
1264 
1265 	return 0;
1266 
1267 error_pcm:
1268 
1269 	if (!ssi_private->has_ipg_clk_name)
1270 		clk_disable_unprepare(ssi_private->clk);
1271 	return ret;
1272 }
1273 
1274 static void fsl_ssi_imx_clean(struct platform_device *pdev,
1275 		struct fsl_ssi_private *ssi_private)
1276 {
1277 	if (!ssi_private->use_dma)
1278 		imx_pcm_fiq_exit(pdev);
1279 	if (!ssi_private->has_ipg_clk_name)
1280 		clk_disable_unprepare(ssi_private->clk);
1281 }
1282 
1283 static int fsl_ssi_probe(struct platform_device *pdev)
1284 {
1285 	struct fsl_ssi_private *ssi_private;
1286 	int ret = 0;
1287 	struct device_node *np = pdev->dev.of_node;
1288 	const struct of_device_id *of_id;
1289 	const char *p, *sprop;
1290 	const uint32_t *iprop;
1291 	struct resource *res;
1292 	void __iomem *iomem;
1293 	char name[64];
1294 
1295 	of_id = of_match_device(fsl_ssi_ids, &pdev->dev);
1296 	if (!of_id || !of_id->data)
1297 		return -EINVAL;
1298 
1299 	ssi_private = devm_kzalloc(&pdev->dev, sizeof(*ssi_private),
1300 			GFP_KERNEL);
1301 	if (!ssi_private) {
1302 		dev_err(&pdev->dev, "could not allocate DAI object\n");
1303 		return -ENOMEM;
1304 	}
1305 
1306 	ssi_private->soc = of_id->data;
1307 
1308 	sprop = of_get_property(np, "fsl,mode", NULL);
1309 	if (sprop) {
1310 		if (!strcmp(sprop, "ac97-slave"))
1311 			ssi_private->dai_fmt = SND_SOC_DAIFMT_AC97;
1312 	}
1313 
1314 	ssi_private->use_dma = !of_property_read_bool(np,
1315 			"fsl,fiq-stream-filter");
1316 
1317 	if (fsl_ssi_is_ac97(ssi_private)) {
1318 		memcpy(&ssi_private->cpu_dai_drv, &fsl_ssi_ac97_dai,
1319 				sizeof(fsl_ssi_ac97_dai));
1320 
1321 		fsl_ac97_data = ssi_private;
1322 
1323 		snd_soc_set_ac97_ops_of_reset(&fsl_ssi_ac97_ops, pdev);
1324 	} else {
1325 		/* Initialize this copy of the CPU DAI driver structure */
1326 		memcpy(&ssi_private->cpu_dai_drv, &fsl_ssi_dai_template,
1327 		       sizeof(fsl_ssi_dai_template));
1328 	}
1329 	ssi_private->cpu_dai_drv.name = dev_name(&pdev->dev);
1330 
1331 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1332 	iomem = devm_ioremap_resource(&pdev->dev, res);
1333 	if (IS_ERR(iomem))
1334 		return PTR_ERR(iomem);
1335 	ssi_private->ssi_phys = res->start;
1336 
1337 	ret = of_property_match_string(np, "clock-names", "ipg");
1338 	if (ret < 0) {
1339 		ssi_private->has_ipg_clk_name = false;
1340 		ssi_private->regs = devm_regmap_init_mmio(&pdev->dev, iomem,
1341 			&fsl_ssi_regconfig);
1342 	} else {
1343 		ssi_private->has_ipg_clk_name = true;
1344 		ssi_private->regs = devm_regmap_init_mmio_clk(&pdev->dev,
1345 			"ipg", iomem, &fsl_ssi_regconfig);
1346 	}
1347 	if (IS_ERR(ssi_private->regs)) {
1348 		dev_err(&pdev->dev, "Failed to init register map\n");
1349 		return PTR_ERR(ssi_private->regs);
1350 	}
1351 
1352 	ssi_private->irq = platform_get_irq(pdev, 0);
1353 	if (ssi_private->irq < 0) {
1354 		dev_err(&pdev->dev, "no irq for node %s\n", pdev->name);
1355 		return ssi_private->irq;
1356 	}
1357 
1358 	/* Are the RX and the TX clocks locked? */
1359 	if (!of_find_property(np, "fsl,ssi-asynchronous", NULL)) {
1360 		ssi_private->cpu_dai_drv.symmetric_rates = 1;
1361 		ssi_private->cpu_dai_drv.symmetric_channels = 1;
1362 		ssi_private->cpu_dai_drv.symmetric_samplebits = 1;
1363 	}
1364 
1365 	/* Determine the FIFO depth. */
1366 	iprop = of_get_property(np, "fsl,fifo-depth", NULL);
1367 	if (iprop)
1368 		ssi_private->fifo_depth = be32_to_cpup(iprop);
1369 	else
1370                 /* Older 8610 DTs didn't have the fifo-depth property */
1371 		ssi_private->fifo_depth = 8;
1372 
1373 	dev_set_drvdata(&pdev->dev, ssi_private);
1374 
1375 	if (ssi_private->soc->imx) {
1376 		ret = fsl_ssi_imx_probe(pdev, ssi_private, iomem);
1377 		if (ret)
1378 			return ret;
1379 	}
1380 
1381 	ret = devm_snd_soc_register_component(&pdev->dev, &fsl_ssi_component,
1382 					      &ssi_private->cpu_dai_drv, 1);
1383 	if (ret) {
1384 		dev_err(&pdev->dev, "failed to register DAI: %d\n", ret);
1385 		goto error_asoc_register;
1386 	}
1387 
1388 	if (ssi_private->use_dma) {
1389 		ret = devm_request_irq(&pdev->dev, ssi_private->irq,
1390 					fsl_ssi_isr, 0, dev_name(&pdev->dev),
1391 					ssi_private);
1392 		if (ret < 0) {
1393 			dev_err(&pdev->dev, "could not claim irq %u\n",
1394 					ssi_private->irq);
1395 			goto error_asoc_register;
1396 		}
1397 	}
1398 
1399 	ret = fsl_ssi_debugfs_create(&ssi_private->dbg_stats, &pdev->dev);
1400 	if (ret)
1401 		goto error_asoc_register;
1402 
1403 	/*
1404 	 * If codec-handle property is missing from SSI node, we assume
1405 	 * that the machine driver uses new binding which does not require
1406 	 * SSI driver to trigger machine driver's probe.
1407 	 */
1408 	if (!of_get_property(np, "codec-handle", NULL))
1409 		goto done;
1410 
1411 	/* Trigger the machine driver's probe function.  The platform driver
1412 	 * name of the machine driver is taken from /compatible property of the
1413 	 * device tree.  We also pass the address of the CPU DAI driver
1414 	 * structure.
1415 	 */
1416 	sprop = of_get_property(of_find_node_by_path("/"), "compatible", NULL);
1417 	/* Sometimes the compatible name has a "fsl," prefix, so we strip it. */
1418 	p = strrchr(sprop, ',');
1419 	if (p)
1420 		sprop = p + 1;
1421 	snprintf(name, sizeof(name), "snd-soc-%s", sprop);
1422 	make_lowercase(name);
1423 
1424 	ssi_private->pdev =
1425 		platform_device_register_data(&pdev->dev, name, 0, NULL, 0);
1426 	if (IS_ERR(ssi_private->pdev)) {
1427 		ret = PTR_ERR(ssi_private->pdev);
1428 		dev_err(&pdev->dev, "failed to register platform: %d\n", ret);
1429 		goto error_sound_card;
1430 	}
1431 
1432 done:
1433 	if (ssi_private->dai_fmt)
1434 		_fsl_ssi_set_dai_fmt(&pdev->dev, ssi_private,
1435 				     ssi_private->dai_fmt);
1436 
1437 	return 0;
1438 
1439 error_sound_card:
1440 	fsl_ssi_debugfs_remove(&ssi_private->dbg_stats);
1441 
1442 error_asoc_register:
1443 	if (ssi_private->soc->imx)
1444 		fsl_ssi_imx_clean(pdev, ssi_private);
1445 
1446 	return ret;
1447 }
1448 
1449 static int fsl_ssi_remove(struct platform_device *pdev)
1450 {
1451 	struct fsl_ssi_private *ssi_private = dev_get_drvdata(&pdev->dev);
1452 
1453 	fsl_ssi_debugfs_remove(&ssi_private->dbg_stats);
1454 
1455 	if (ssi_private->pdev)
1456 		platform_device_unregister(ssi_private->pdev);
1457 
1458 	if (ssi_private->soc->imx)
1459 		fsl_ssi_imx_clean(pdev, ssi_private);
1460 
1461 	return 0;
1462 }
1463 
1464 static struct platform_driver fsl_ssi_driver = {
1465 	.driver = {
1466 		.name = "fsl-ssi-dai",
1467 		.of_match_table = fsl_ssi_ids,
1468 	},
1469 	.probe = fsl_ssi_probe,
1470 	.remove = fsl_ssi_remove,
1471 };
1472 
1473 module_platform_driver(fsl_ssi_driver);
1474 
1475 MODULE_ALIAS("platform:fsl-ssi-dai");
1476 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
1477 MODULE_DESCRIPTION("Freescale Synchronous Serial Interface (SSI) ASoC Driver");
1478 MODULE_LICENSE("GPL v2");
1479