ASoC: fsl: add memory to memory function for ASRC

Merge series from Shengjiu Wang <[e-mail]>:

This function is base on the accelerator implementation
for compress API:
04177158cf98 ("ALSA: compress_offload: introduce accel operation mode")

Audio signal processing also has the requirement for memory to
memory similar as Video.

This asrc memory to memory (memory ->asrc->memory) case is a non
real time use case.

User fills the input buffer to the asrc module, after conversion, then asrc
sends back the output buffer to user. So it is not a traditional ALSA playback
and capture case.

Because we had implemented the "memory -> asrc ->i2s device-> codec"
use case in ALSA. Now the "memory->asrc->memory" needs
to reuse the code in asrc driver, so the patch 1 and patch 2 is for refining
the code to make it can be shared by the "memory->asrc->memory"
driver.

Other change is to add memory to memory support for two kinds of i.MX ASRC
modules.

include/uapi/sound/compress_params.h

···
 	struct snd_dec_wma wma_d;
 	struct snd_dec_alac alac_d;
 	struct snd_dec_ape ape_d;
+	struct {
+		__u32 out_sample_rate;
+	} src_d;
+} __attribute__((packed, aligned(4)));
+
+struct snd_codec_desc_src {
+	__u32 out_sample_rate_min;
+	__u32 out_sample_rate_max;
 } __attribute__((packed, aligned(4)));
 
 /** struct snd_codec_desc - description of codec capabilities
···
  * @modes: Supported modes. See SND_AUDIOMODE defines
  * @formats: Supported formats. See SND_AUDIOSTREAMFORMAT defines
  * @min_buffer: Minimum buffer size handled by codec implementation
+ * @pcm_formats: Output (for decoders) or input (for encoders)
+ *               PCM formats (required to accel mode, 0 for other modes)
+ * @u_space: union space (for codec dependent data)
  * @reserved: reserved for future use
  *
  * This structure provides a scalar value for profiles, modes and stream
···
 	__u32 modes;
 	__u32 formats;
 	__u32 min_buffer;
-	__u32 reserved[15];
+	__u32 pcm_formats;
+	union {
+		__u32 u_space[6];
+		struct snd_codec_desc_src src;
+	} __attribute__((packed, aligned(4)));
+	__u32 reserved[8];
 } __attribute__((packed, aligned(4)));
 
 /** struct snd_codec
···
  * @align: Block alignment in bytes of an audio sample.
  *		Only required for PCM or IEC formats.
  * @options: encoder-specific settings
+ * @pcm_format: Output (for decoders) or input (for encoders)
+ *               PCM formats (required to accel mode, 0 for other modes)
  * @reserved: reserved for future use
  */
 
···
 	__u32 format;
 	__u32 align;
 	union snd_codec_options options;
-	__u32 reserved[3];
+	__u32 pcm_format;
+	__u32 reserved[2];
 } __attribute__((packed, aligned(4)));
 
 #endif

sound/soc/fsl/Kconfig

···
 	depends on HAS_DMA
 	select REGMAP_MMIO
 	select SND_SOC_GENERIC_DMAENGINE_PCM
+	select SND_COMPRESS_ACCEL
+	select SND_COMPRESS_OFFLOAD
 	help
 	  Say Y if you want to add Asynchronous Sample Rate Converter (ASRC)
 	  support for the Freescale CPUs.

sound/soc/fsl/Makefile

···
 # Freescale SSI/DMA/SAI/SPDIF Support
 snd-soc-fsl-audmix-y := fsl_audmix.o
 snd-soc-fsl-asoc-card-y := fsl-asoc-card.o
-snd-soc-fsl-asrc-y := fsl_asrc.o fsl_asrc_dma.o
+snd-soc-fsl-asrc-y := fsl_asrc.o fsl_asrc_dma.o fsl_asrc_m2m.o
 snd-soc-fsl-lpc3xxx-y := lpc3xxx-pcm.o lpc3xxx-i2s.o
 snd-soc-fsl-sai-y := fsl_sai.o
 snd-soc-fsl-ssi-y := fsl_ssi.o

sound/soc/fsl/fsl_asrc.c

···
 	return REG_ASRDx(dir, index);
 }
 
+/* Get sample numbers in FIFO */
+static unsigned int fsl_asrc_get_output_fifo_size(struct fsl_asrc_pair *pair)
+{
+	struct fsl_asrc *asrc = pair->asrc;
+	enum asrc_pair_index index = pair->index;
+	u32 val;
+
+	regmap_read(asrc->regmap, REG_ASRFST(index), &val);
+
+	val &= ASRFSTi_OUTPUT_FIFO_MASK;
+
+	return val >> ASRFSTi_OUTPUT_FIFO_SHIFT;
+}
+
+static int fsl_asrc_m2m_prepare(struct fsl_asrc_pair *pair)
+{
+	struct fsl_asrc_pair_priv *pair_priv = pair->private;
+	struct fsl_asrc *asrc = pair->asrc;
+	struct device *dev = &asrc->pdev->dev;
+	struct asrc_config config;
+	int ret;
+
+	/* fill config */
+	config.pair = pair->index;
+	config.channel_num = pair->channels;
+	config.input_sample_rate = pair->rate[IN];
+	config.output_sample_rate = pair->rate[OUT];
+	config.input_format = pair->sample_format[IN];
+	config.output_format = pair->sample_format[OUT];
+	config.inclk = INCLK_NONE;
+	config.outclk = OUTCLK_ASRCK1_CLK;
+
+	pair_priv->config = &config;
+	ret = fsl_asrc_config_pair(pair, true);
+	if (ret) {
+		dev_err(dev, "failed to config pair: %d\n", ret);
+		return ret;
+	}
+
+	pair->first_convert = 1;
+
+	return 0;
+}
+
+static int fsl_asrc_m2m_start(struct fsl_asrc_pair *pair)
+{
+	if (pair->first_convert) {
+		fsl_asrc_start_pair(pair);
+		pair->first_convert = 0;
+	}
+	/*
+	 * Clear DMA request during the stall state of ASRC:
+	 * During STALL state, the remaining in input fifo would never be
+	 * smaller than the input threshold while the output fifo would not
+	 * be bigger than output one. Thus the DMA request would be cleared.
+	 */
+	fsl_asrc_set_watermarks(pair, ASRC_FIFO_THRESHOLD_MIN,
+				ASRC_FIFO_THRESHOLD_MAX);
+
+	/* Update the real input threshold to raise DMA request */
+	fsl_asrc_set_watermarks(pair, ASRC_M2M_INPUTFIFO_WML,
+				ASRC_M2M_OUTPUTFIFO_WML);
+
+	return 0;
+}
+
+static int fsl_asrc_m2m_stop(struct fsl_asrc_pair *pair)
+{
+	if (!pair->first_convert) {
+		fsl_asrc_stop_pair(pair);
+		pair->first_convert = 1;
+	}
+
+	return 0;
+}
+
+/* calculate capture data length according to output data length and sample rate */
+static int fsl_asrc_m2m_calc_out_len(struct fsl_asrc_pair *pair, int input_buffer_length)
+{
+	unsigned int in_width, out_width;
+	unsigned int channels = pair->channels;
+	unsigned int in_samples, out_samples;
+	unsigned int out_length;
+
+	in_width = snd_pcm_format_physical_width(pair->sample_format[IN]) / 8;
+	out_width = snd_pcm_format_physical_width(pair->sample_format[OUT]) / 8;
+
+	in_samples = input_buffer_length / in_width / channels;
+	out_samples = pair->rate[OUT] * in_samples / pair->rate[IN];
+	out_length = (out_samples - ASRC_OUTPUT_LAST_SAMPLE) * out_width * channels;
+
+	return out_length;
+}
+
+static int fsl_asrc_m2m_get_maxburst(u8 dir, struct fsl_asrc_pair *pair)
+{
+	struct fsl_asrc *asrc = pair->asrc;
+	struct fsl_asrc_priv *asrc_priv = asrc->private;
+	int wml = (dir == IN) ? ASRC_M2M_INPUTFIFO_WML : ASRC_M2M_OUTPUTFIFO_WML;
+
+	if (!asrc_priv->soc->use_edma)
+		return wml * pair->channels;
+	else
+		return 1;
+}
+
+static int fsl_asrc_m2m_get_cap(struct fsl_asrc_m2m_cap *cap)
+{
+	cap->fmt_in = FSL_ASRC_FORMATS;
+	cap->fmt_out = FSL_ASRC_FORMATS | SNDRV_PCM_FMTBIT_S8;
+
+	cap->rate_in = supported_asrc_rate;
+	cap->rate_in_count = ARRAY_SIZE(supported_asrc_rate);
+	cap->rate_out = supported_asrc_rate;
+	cap->rate_out_count = ARRAY_SIZE(supported_asrc_rate);
+	cap->chan_min = 1;
+	cap->chan_max = 10;
+
+	return 0;
+}
+
+static int fsl_asrc_m2m_pair_resume(struct fsl_asrc_pair *pair)
+{
+	struct fsl_asrc *asrc = pair->asrc;
+	int i;
+
+	for (i = 0; i < pair->channels * 4; i++)
+		regmap_write(asrc->regmap, REG_ASRDI(pair->index), 0);
+
+	pair->first_convert = 1;
+	return 0;
+}
+
 static int fsl_asrc_runtime_resume(struct device *dev);
 static int fsl_asrc_runtime_suspend(struct device *dev);
 
···
 	asrc->release_pair = fsl_asrc_release_pair;
 	asrc->get_fifo_addr = fsl_asrc_get_fifo_addr;
 	asrc->pair_priv_size = sizeof(struct fsl_asrc_pair_priv);
+
+	asrc->m2m_prepare = fsl_asrc_m2m_prepare;
+	asrc->m2m_start = fsl_asrc_m2m_start;
+	asrc->m2m_stop = fsl_asrc_m2m_stop;
+	asrc->get_output_fifo_size = fsl_asrc_get_output_fifo_size;
+	asrc->m2m_calc_out_len = fsl_asrc_m2m_calc_out_len;
+	asrc->m2m_get_maxburst = fsl_asrc_m2m_get_maxburst;
+	asrc->m2m_pair_resume = fsl_asrc_m2m_pair_resume;
+	asrc->m2m_get_cap = fsl_asrc_m2m_get_cap;
 
 	if (of_device_is_compatible(np, "fsl,imx35-asrc")) {
 		asrc_priv->clk_map[IN] = input_clk_map_imx35;
···
 		goto err_pm_get_sync;
 	}
 
+	ret = fsl_asrc_m2m_init(asrc);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to init m2m device %d\n", ret);
+		return ret;
+	}
+
 	return 0;
 
 err_pm_get_sync:
···
 
 static void fsl_asrc_remove(struct platform_device *pdev)
 {
+	struct fsl_asrc *asrc = dev_get_drvdata(&pdev->dev);
+
+	fsl_asrc_m2m_exit(asrc);
+
 	pm_runtime_disable(&pdev->dev);
 	if (!pm_runtime_status_suspended(&pdev->dev))
 		fsl_asrc_runtime_suspend(&pdev->dev);
···
 	return 0;
 }
 
+static int fsl_asrc_suspend(struct device *dev)
+{
+	struct fsl_asrc *asrc = dev_get_drvdata(dev);
+	int ret;
+
+	fsl_asrc_m2m_suspend(asrc);
+	ret = pm_runtime_force_suspend(dev);
+	return ret;
+}
+
+static int fsl_asrc_resume(struct device *dev)
+{
+	struct fsl_asrc *asrc = dev_get_drvdata(dev);
+	int ret;
+
+	ret = pm_runtime_force_resume(dev);
+	fsl_asrc_m2m_resume(asrc);
+	return ret;
+}
+
 static const struct dev_pm_ops fsl_asrc_pm = {
-	SET_RUNTIME_PM_OPS(fsl_asrc_runtime_suspend, fsl_asrc_runtime_resume, NULL)
-	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
-				pm_runtime_force_resume)
+	RUNTIME_PM_OPS(fsl_asrc_runtime_suspend, fsl_asrc_runtime_resume, NULL)
+	SYSTEM_SLEEP_PM_OPS(fsl_asrc_suspend, fsl_asrc_resume)
 };
 
 static const struct fsl_asrc_soc_data fsl_asrc_imx35_data = {
···
 	.driver = {
 		.name = "fsl-asrc",
 		.of_match_table = fsl_asrc_ids,
-		.pm = &fsl_asrc_pm,
+		.pm = pm_ptr(&fsl_asrc_pm),
 	},
 };
 module_platform_driver(fsl_asrc_driver);

sound/soc/fsl/fsl_asrc.h

···
 
 #include  "fsl_asrc_common.h"
 
+#define ASRC_M2M_INPUTFIFO_WML		0x4
+#define ASRC_M2M_OUTPUTFIFO_WML		0x2
 #define ASRC_DMA_BUFFER_NUM		2
 #define ASRC_INPUTFIFO_THRESHOLD	32
 #define ASRC_OUTPUTFIFO_THRESHOLD	32

sound/soc/fsl/fsl_asrc_common.h

···
 #define PAIR_CTX_NUM  0x4
 
 /**
+ * struct fsl_asrc_m2m_cap - capability data
+ * @fmt_in: input sample format
+ * @fmt_out: output sample format
+ * @chan_min: minimum channel number
+ * @chan_max: maximum channel number
+ * @rate_in: minimum rate
+ * @rate_out: maximum rete
+ */
+struct fsl_asrc_m2m_cap {
+	u64 fmt_in;
+	u64 fmt_out;
+	int chan_min;
+	int chan_max;
+	const unsigned int *rate_in;
+	int rate_in_count;
+	const unsigned int *rate_out;
+	int rate_out_count;
+};
+
+/**
  * fsl_asrc_pair: ASRC Pair common data
  *
  * @asrc: pointer to its parent module
···
  * @pos: hardware pointer position
  * @req_dma_chan: flag to release dev_to_dev chan
  * @private: pair private area
+ * @complete: dma task complete
+ * @sample_format: format of m2m
+ * @rate: rate of m2m
+ * @buf_len: buffer length of m2m
+ * @dma_buffer: buffer pointers
+ * @first_convert: start of conversion
+ * @ratio_mod_flag: flag for new ratio modifier
+ * @ratio_mod: ratio modification
  */
 struct fsl_asrc_pair {
 	struct fsl_asrc *asrc;
···
 	bool req_dma_chan;
 
 	void *private;
+
+	/* used for m2m */
+	struct completion complete[2];
+	snd_pcm_format_t sample_format[2];
+	unsigned int rate[2];
+	unsigned int buf_len[2];
+	struct snd_dma_buffer dma_buffer[2];
+	unsigned int first_convert;
+	bool ratio_mod_flag;
+	unsigned int ratio_mod;
 };
 
 /**
···
  * @mem_clk: clock source to access register
  * @ipg_clk: clock source to drive peripheral
  * @spba_clk: SPBA clock (optional, depending on SoC design)
+ * @card: compress sound card
  * @lock: spin lock for resource protection
  * @pair: pair pointers
  * @channel_avail: non-occupied channel numbers
···
  * @request_pair: function pointer
  * @release_pair: function pointer
  * @get_fifo_addr: function pointer
+ * @m2m_get_cap: function pointer
+ * @m2m_prepare: function pointer
+ * @m2m_start: function pointer
+ * @m2m_unprepare: function pointer
+ * @m2m_stop: function pointer
+ * @m2m_calc_out_len: function pointer
+ * @m2m_get_maxburst: function pointer
+ * @m2m_pair_suspend: function pointer
+ * @m2m_pair_resume: function pointer
+ * @m2m_set_ratio_mod: function pointer
+ * @get_output_fifo_size: function pointer
  * @pair_priv_size: size of pair private struct.
  * @private: private data structure
  */
···
 	struct clk *mem_clk;
 	struct clk *ipg_clk;
 	struct clk *spba_clk;
+	struct snd_card *card;
 	spinlock_t lock;      /* spin lock for resource protection */
 
 	struct fsl_asrc_pair *pair[PAIR_CTX_NUM];
···
 	int (*request_pair)(int channels, struct fsl_asrc_pair *pair);
 	void (*release_pair)(struct fsl_asrc_pair *pair);
 	int (*get_fifo_addr)(u8 dir, enum asrc_pair_index index);
+	int (*m2m_get_cap)(struct fsl_asrc_m2m_cap *cap);
+
+	int (*m2m_prepare)(struct fsl_asrc_pair *pair);
+	int (*m2m_start)(struct fsl_asrc_pair *pair);
+	int (*m2m_unprepare)(struct fsl_asrc_pair *pair);
+	int (*m2m_stop)(struct fsl_asrc_pair *pair);
+
+	int (*m2m_calc_out_len)(struct fsl_asrc_pair *pair, int input_buffer_length);
+	int (*m2m_get_maxburst)(u8 dir, struct fsl_asrc_pair *pair);
+	int (*m2m_pair_suspend)(struct fsl_asrc_pair *pair);
+	int (*m2m_pair_resume)(struct fsl_asrc_pair *pair);
+	int (*m2m_set_ratio_mod)(struct fsl_asrc_pair *pair, int val);
+
+	unsigned int (*get_output_fifo_size)(struct fsl_asrc_pair *pair);
 	size_t pair_priv_size;
 
 	void *private;
···
 
 #define DRV_NAME "fsl-asrc-dai"
 extern struct snd_soc_component_driver fsl_asrc_component;
+
+int fsl_asrc_m2m_init(struct fsl_asrc *asrc);
+void fsl_asrc_m2m_exit(struct fsl_asrc *asrc);
+int fsl_asrc_m2m_resume(struct fsl_asrc *asrc);
+int fsl_asrc_m2m_suspend(struct fsl_asrc *asrc);
 
 #endif /* _FSL_ASRC_COMMON_H */

sound/soc/fsl/fsl_asrc_m2m.c

···
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (C) 2014-2016 Freescale Semiconductor, Inc.
+// Copyright (C) 2019-2024 NXP
+//
+// Freescale ASRC Memory to Memory (M2M) driver
+
+#include <linux/dma/imx-dma.h>
+#include <linux/dma-buf.h>
+#include <linux/dma-mapping.h>
+#include <linux/pm_runtime.h>
+#include <sound/asound.h>
+#include <sound/dmaengine_pcm.h>
+#include <sound/initval.h>
+
+#include "fsl_asrc_common.h"
+
+#define DIR_STR(dir) (dir) == IN ? "in" : "out"
+
+#define ASRC_xPUT_DMA_CALLBACK(dir) \
+	(((dir) == IN) ? asrc_input_dma_callback \
+	: asrc_output_dma_callback)
+
+/* Maximum output and capture buffer size */
+#define ASRC_M2M_BUFFER_SIZE (512 * 1024)
+
+/* Maximum output and capture period size */
+#define ASRC_M2M_PERIOD_SIZE (48 * 1024)
+
+/* dma complete callback */
+static void asrc_input_dma_callback(void *data)
+{
+	struct fsl_asrc_pair *pair = (struct fsl_asrc_pair *)data;
+
+	complete(&pair->complete[IN]);
+}
+
+/* dma complete callback */
+static void asrc_output_dma_callback(void *data)
+{
+	struct fsl_asrc_pair *pair = (struct fsl_asrc_pair *)data;
+
+	complete(&pair->complete[OUT]);
+}
+
+/**
+ *asrc_read_last_fifo: read all the remaining data from FIFO
+ *@pair: Structure pointer of fsl_asrc_pair
+ *@dma_vaddr: virtual address of capture buffer
+ *@length: payload length of capture buffer
+ */
+static void asrc_read_last_fifo(struct fsl_asrc_pair *pair, void *dma_vaddr, u32 *length)
+{
+	struct fsl_asrc *asrc = pair->asrc;
+	enum asrc_pair_index index = pair->index;
+	u32 i, reg, size, t_size = 0, width;
+	u32 *reg32 = NULL;
+	u16 *reg16 = NULL;
+	u8  *reg24 = NULL;
+
+	width = snd_pcm_format_physical_width(pair->sample_format[OUT]);
+	if (width == 32)
+		reg32 = dma_vaddr + *length;
+	else if (width == 16)
+		reg16 = dma_vaddr + *length;
+	else
+		reg24 = dma_vaddr + *length;
+retry:
+	size = asrc->get_output_fifo_size(pair);
+	if (size + *length > ASRC_M2M_BUFFER_SIZE)
+		goto end;
+
+	for (i = 0; i < size * pair->channels; i++) {
+		regmap_read(asrc->regmap, asrc->get_fifo_addr(OUT, index), &reg);
+		if (reg32) {
+			*reg32++ = reg;
+		} else if (reg16) {
+			*reg16++ = (u16)reg;
+		} else {
+			*reg24++ = (u8)reg;
+			*reg24++ = (u8)(reg >> 8);
+			*reg24++ = (u8)(reg >> 16);
+		}
+	}
+	t_size += size;
+
+	/* In case there is data left in FIFO */
+	if (size)
+		goto retry;
+end:
+	/* Update payload length */
+	if (reg32)
+		*length += t_size * pair->channels * 4;
+	else if (reg16)
+		*length += t_size * pair->channels * 2;
+	else
+		*length += t_size * pair->channels * 3;
+}
+
+/* config dma channel */
+static int asrc_dmaconfig(struct fsl_asrc_pair *pair,
+			  struct dma_chan *chan,
+			  u32 dma_addr, dma_addr_t buf_addr, u32 buf_len,
+			  int dir, int width)
+{
+	struct fsl_asrc *asrc = pair->asrc;
+	struct device *dev = &asrc->pdev->dev;
+	struct dma_slave_config slave_config;
+	enum dma_slave_buswidth buswidth;
+	unsigned int sg_len, max_period_size;
+	struct scatterlist *sg;
+	int ret, i;
+
+	switch (width) {
+	case 8:
+		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
+		break;
+	case 16:
+		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
+		break;
+	case 24:
+		buswidth = DMA_SLAVE_BUSWIDTH_3_BYTES;
+		break;
+	case 32:
+		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
+		break;
+	default:
+		dev_err(dev, "invalid word width\n");
+		return -EINVAL;
+	}
+
+	memset(&slave_config, 0, sizeof(slave_config));
+	if (dir == IN) {
+		slave_config.direction = DMA_MEM_TO_DEV;
+		slave_config.dst_addr = dma_addr;
+		slave_config.dst_addr_width = buswidth;
+		slave_config.dst_maxburst = asrc->m2m_get_maxburst(IN, pair);
+	} else {
+		slave_config.direction = DMA_DEV_TO_MEM;
+		slave_config.src_addr = dma_addr;
+		slave_config.src_addr_width = buswidth;
+		slave_config.src_maxburst = asrc->m2m_get_maxburst(OUT, pair);
+	}
+
+	ret = dmaengine_slave_config(chan, &slave_config);
+	if (ret) {
+		dev_err(dev, "failed to config dmaengine for %s task: %d\n",
+			DIR_STR(dir), ret);
+		return -EINVAL;
+	}
+
+	max_period_size = rounddown(ASRC_M2M_PERIOD_SIZE, width * pair->channels / 8);
+	/* scatter gather mode */
+	sg_len = buf_len / max_period_size;
+	if (buf_len % max_period_size)
+		sg_len += 1;
+
+	sg = kmalloc_array(sg_len, sizeof(*sg), GFP_KERNEL);
+	if (!sg)
+		return -ENOMEM;
+
+	sg_init_table(sg, sg_len);
+	for (i = 0; i < (sg_len - 1); i++) {
+		sg_dma_address(&sg[i]) = buf_addr + i * max_period_size;
+		sg_dma_len(&sg[i]) = max_period_size;
+	}
+	sg_dma_address(&sg[i]) = buf_addr + i * max_period_size;
+	sg_dma_len(&sg[i]) = buf_len - i * max_period_size;
+
+	pair->desc[dir] = dmaengine_prep_slave_sg(chan, sg, sg_len,
+						  slave_config.direction,
+						  DMA_PREP_INTERRUPT);
+	kfree(sg);
+	if (!pair->desc[dir]) {
+		dev_err(dev, "failed to prepare dmaengine for %s task\n", DIR_STR(dir));
+		return -EINVAL;
+	}
+
+	pair->desc[dir]->callback = ASRC_xPUT_DMA_CALLBACK(dir);
+	pair->desc[dir]->callback_param = pair;
+
+	return 0;
+}
+
+/* main function of converter */
+static void asrc_m2m_device_run(struct fsl_asrc_pair *pair, struct snd_compr_task_runtime *task)
+{
+	struct fsl_asrc *asrc = pair->asrc;
+	struct device *dev = &asrc->pdev->dev;
+	enum asrc_pair_index index = pair->index;
+	struct snd_dma_buffer *src_buf, *dst_buf;
+	unsigned int in_buf_len;
+	unsigned int out_dma_len;
+	unsigned int width;
+	u32 fifo_addr;
+	int ret;
+
+	/* set ratio mod */
+	if (asrc->m2m_set_ratio_mod) {
+		if (pair->ratio_mod_flag) {
+			asrc->m2m_set_ratio_mod(pair, pair->ratio_mod);
+			pair->ratio_mod_flag = false;
+		}
+	}
+
+	src_buf = &pair->dma_buffer[IN];
+	dst_buf = &pair->dma_buffer[OUT];
+
+	width = snd_pcm_format_physical_width(pair->sample_format[IN]);
+	fifo_addr = asrc->paddr + asrc->get_fifo_addr(IN, index);
+
+	in_buf_len = task->input_size;
+
+	if (in_buf_len < width * pair->channels / 8 ||
+	    in_buf_len > ASRC_M2M_BUFFER_SIZE ||
+	    in_buf_len % (width * pair->channels / 8)) {
+		dev_err(dev, "out buffer size is error: [%d]\n", in_buf_len);
+		goto end;
+	}
+
+	/* dma config for output dma channel */
+	ret = asrc_dmaconfig(pair,
+			     pair->dma_chan[IN],
+			     fifo_addr,
+			     src_buf->addr,
+			     in_buf_len, IN, width);
+	if (ret) {
+		dev_err(dev, "out dma config error\n");
+		goto end;
+	}
+
+	width = snd_pcm_format_physical_width(pair->sample_format[OUT]);
+	fifo_addr = asrc->paddr + asrc->get_fifo_addr(OUT, index);
+	out_dma_len = asrc->m2m_calc_out_len(pair, in_buf_len);
+	if (out_dma_len > 0 && out_dma_len <= ASRC_M2M_BUFFER_SIZE) {
+		/* dma config for capture dma channel */
+		ret = asrc_dmaconfig(pair,
+				     pair->dma_chan[OUT],
+				     fifo_addr,
+				     dst_buf->addr,
+				     out_dma_len, OUT, width);
+		if (ret) {
+			dev_err(dev, "cap dma config error\n");
+			goto end;
+		}
+	} else if (out_dma_len > ASRC_M2M_BUFFER_SIZE) {
+		dev_err(dev, "cap buffer size error\n");
+		goto end;
+	}
+
+	reinit_completion(&pair->complete[IN]);
+	reinit_completion(&pair->complete[OUT]);
+
+	/* Submit DMA request */
+	dmaengine_submit(pair->desc[IN]);
+	dma_async_issue_pending(pair->desc[IN]->chan);
+	if (out_dma_len > 0) {
+		dmaengine_submit(pair->desc[OUT]);
+		dma_async_issue_pending(pair->desc[OUT]->chan);
+	}
+
+	asrc->m2m_start(pair);
+
+	if (!wait_for_completion_interruptible_timeout(&pair->complete[IN], 10 * HZ)) {
+		dev_err(dev, "out DMA task timeout\n");
+		goto end;
+	}
+
+	if (out_dma_len > 0) {
+		if (!wait_for_completion_interruptible_timeout(&pair->complete[OUT], 10 * HZ)) {
+			dev_err(dev, "cap DMA task timeout\n");
+			goto end;
+		}
+	}
+
+	/* read the last words from FIFO */
+	asrc_read_last_fifo(pair, dst_buf->area, &out_dma_len);
+	/* update payload length for capture */
+	task->output_size = out_dma_len;
+end:
+	return;
+}
+
+static int fsl_asrc_m2m_comp_open(struct snd_compr_stream *stream)
+{
+	struct fsl_asrc *asrc = stream->private_data;
+	struct snd_compr_runtime *runtime = stream->runtime;
+	struct device *dev = &asrc->pdev->dev;
+	struct fsl_asrc_pair *pair;
+	int size, ret;
+
+	pair = kzalloc(sizeof(*pair) + asrc->pair_priv_size, GFP_KERNEL);
+	if (!pair)
+		return -ENOMEM;
+
+	pair->private = (void *)pair + sizeof(struct fsl_asrc_pair);
+	pair->asrc = asrc;
+
+	init_completion(&pair->complete[IN]);
+	init_completion(&pair->complete[OUT]);
+
+	runtime->private_data = pair;
+
+	size = ASRC_M2M_BUFFER_SIZE;
+	ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, dev, size, &pair->dma_buffer[IN]);
+	if (ret)
+		goto error_alloc_in_buf;
+
+	ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, dev, size, &pair->dma_buffer[OUT]);
+	if (ret)
+		goto error_alloc_out_buf;
+
+	ret = pm_runtime_get_sync(dev);
+	if (ret < 0) {
+		dev_err(dev, "Failed to power up asrc\n");
+		goto err_pm_runtime;
+	}
+
+	return 0;
+
+err_pm_runtime:
+	snd_dma_free_pages(&pair->dma_buffer[OUT]);
+error_alloc_out_buf:
+	snd_dma_free_pages(&pair->dma_buffer[IN]);
+error_alloc_in_buf:
+	kfree(pair);
+	return ret;
+}
+
+static int fsl_asrc_m2m_comp_release(struct snd_compr_stream *stream)
+{
+	struct fsl_asrc *asrc = stream->private_data;
+	struct snd_compr_runtime *runtime = stream->runtime;
+	struct fsl_asrc_pair *pair = runtime->private_data;
+	struct device *dev = &asrc->pdev->dev;
+
+	pm_runtime_put_sync(dev);
+
+	snd_dma_free_pages(&pair->dma_buffer[IN]);
+	snd_dma_free_pages(&pair->dma_buffer[OUT]);
+
+	kfree(runtime->private_data);
+
+	return 0;
+}
+
+static int fsl_asrc_m2m_comp_set_params(struct snd_compr_stream *stream,
+					struct snd_compr_params *params)
+{
+	struct fsl_asrc *asrc = stream->private_data;
+	struct snd_compr_runtime *runtime = stream->runtime;
+	struct fsl_asrc_pair *pair = runtime->private_data;
+	struct fsl_asrc_m2m_cap cap;
+	int ret, i;
+
+	ret = asrc->m2m_get_cap(&cap);
+	if (ret)
+		return -EINVAL;
+
+	if (pcm_format_to_bits(params->codec.format) & cap.fmt_in)
+		pair->sample_format[IN] = params->codec.format;
+	else
+		return -EINVAL;
+
+	if (pcm_format_to_bits(params->codec.pcm_format) & cap.fmt_out)
+		pair->sample_format[OUT] = params->codec.pcm_format;
+	else
+		return -EINVAL;
+
+	/* check input rate is in scope */
+	for (i = 0; i < cap.rate_in_count; i++)
+		if (params->codec.sample_rate == cap.rate_in[i]) {
+			pair->rate[IN] = params->codec.sample_rate;
+			break;
+		}
+	if (i == cap.rate_in_count)
+		return -EINVAL;
+
+	/* check output rate is in scope */
+	for (i = 0; i < cap.rate_out_count; i++)
+		if (params->codec.options.src_d.out_sample_rate == cap.rate_out[i]) {
+			pair->rate[OUT] = params->codec.options.src_d.out_sample_rate;
+			break;
+		}
+	if (i == cap.rate_out_count)
+		return -EINVAL;
+
+	if (params->codec.ch_in != params->codec.ch_out ||
+	    params->codec.ch_in < cap.chan_min ||
+	    params->codec.ch_in > cap.chan_max)
+		return -EINVAL;
+
+	pair->channels = params->codec.ch_in;
+	pair->buf_len[IN] = params->buffer.fragment_size;
+	pair->buf_len[OUT] = params->buffer.fragment_size;
+
+	return 0;
+}
+
+static int fsl_asrc_m2m_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)
+{
+	struct snd_dma_buffer *dmab = dmabuf->priv;
+
+	return snd_dma_buffer_mmap(dmab, vma);
+}
+
+static struct sg_table *fsl_asrc_m2m_map_dma_buf(struct dma_buf_attachment *attachment,
+						 enum dma_data_direction direction)
+{
+	struct snd_dma_buffer *dmab = attachment->dmabuf->priv;
+	struct sg_table *sgt;
+
+	sgt = kmalloc(sizeof(*sgt), GFP_KERNEL);
+	if (!sgt)
+		return NULL;
+
+	if (dma_get_sgtable(attachment->dev, sgt, dmab->area, dmab->addr, dmab->bytes) < 0)
+		goto free;
+
+	if (dma_map_sgtable(attachment->dev, sgt, direction, 0))
+		goto free;
+
+	return sgt;
+
+free:
+	sg_free_table(sgt);
+	kfree(sgt);
+	return NULL;
+}
+
+static void fsl_asrc_m2m_unmap_dma_buf(struct dma_buf_attachment *attachment,
+				       struct sg_table *table,
+				       enum dma_data_direction direction)
+{
+	dma_unmap_sgtable(attachment->dev, table, direction, 0);
+}
+
+static void fsl_asrc_m2m_release(struct dma_buf *dmabuf)
+{
+	/* buffer is released by fsl_asrc_m2m_comp_release() */
+}
+
+static const struct dma_buf_ops fsl_asrc_m2m_dma_buf_ops = {
+	.mmap = fsl_asrc_m2m_mmap,
+	.map_dma_buf = fsl_asrc_m2m_map_dma_buf,
+	.unmap_dma_buf = fsl_asrc_m2m_unmap_dma_buf,
+	.release = fsl_asrc_m2m_release,
+};
+
+static int fsl_asrc_m2m_comp_task_create(struct snd_compr_stream *stream,
+					 struct snd_compr_task_runtime *task)
+{
+	DEFINE_DMA_BUF_EXPORT_INFO(exp_info_in);
+	DEFINE_DMA_BUF_EXPORT_INFO(exp_info_out);
+	struct fsl_asrc *asrc = stream->private_data;
+	struct snd_compr_runtime *runtime = stream->runtime;
+	struct fsl_asrc_pair *pair = runtime->private_data;
+	struct device *dev = &asrc->pdev->dev;
+	int ret;
+
+	exp_info_in.ops = &fsl_asrc_m2m_dma_buf_ops;
+	exp_info_in.size = ASRC_M2M_BUFFER_SIZE;
+	exp_info_in.flags = O_RDWR;
+	exp_info_in.priv = &pair->dma_buffer[IN];
+	task->input = dma_buf_export(&exp_info_in);
+	if (IS_ERR(task->input)) {
+		ret = PTR_ERR(task->input);
+		return ret;
+	}
+
+	exp_info_out.ops = &fsl_asrc_m2m_dma_buf_ops;
+	exp_info_out.size = ASRC_M2M_BUFFER_SIZE;
+	exp_info_out.flags = O_RDWR;
+	exp_info_out.priv = &pair->dma_buffer[OUT];
+	task->output = dma_buf_export(&exp_info_out);
+	if (IS_ERR(task->output)) {
+		ret = PTR_ERR(task->output);
+		return ret;
+	}
+
+	/* Request asrc pair/context */
+	ret = asrc->request_pair(pair->channels, pair);
+	if (ret) {
+		dev_err(dev, "failed to request pair: %d\n", ret);
+		goto err_request_pair;
+	}
+
+	ret = asrc->m2m_prepare(pair);
+	if (ret) {
+		dev_err(dev, "failed to start pair part one: %d\n", ret);
+		goto err_start_part_one;
+	}
+
+	/* Request dma channels */
+	pair->dma_chan[IN] = asrc->get_dma_channel(pair, IN);
+	if (!pair->dma_chan[IN]) {
+		dev_err(dev, "[ctx%d] failed to get input DMA channel\n", pair->index);
+		ret = -EBUSY;
+		goto err_dma_channel_in;
+	}
+
+	pair->dma_chan[OUT] = asrc->get_dma_channel(pair, OUT);
+	if (!pair->dma_chan[OUT]) {
+		dev_err(dev, "[ctx%d] failed to get output DMA channel\n", pair->index);
+		ret = -EBUSY;
+		goto err_dma_channel_out;
+	}
+
+	return 0;
+
+err_dma_channel_out:
+	dma_release_channel(pair->dma_chan[IN]);
+err_dma_channel_in:
+	if (asrc->m2m_unprepare)
+		asrc->m2m_unprepare(pair);
+err_start_part_one:
+	asrc->release_pair(pair);
+err_request_pair:
+	return ret;
+}
+
+static int fsl_asrc_m2m_comp_task_start(struct snd_compr_stream *stream,
+					struct snd_compr_task_runtime *task)
+{
+	struct snd_compr_runtime *runtime = stream->runtime;
+	struct fsl_asrc_pair *pair = runtime->private_data;
+
+	asrc_m2m_device_run(pair, task);
+
+	return 0;
+}
+
+static int fsl_asrc_m2m_comp_task_stop(struct snd_compr_stream *stream,
+				       struct snd_compr_task_runtime *task)
+{
+	return 0;
+}
+
+static int fsl_asrc_m2m_comp_task_free(struct snd_compr_stream *stream,
+				       struct snd_compr_task_runtime *task)
+{
+	struct fsl_asrc *asrc = stream->private_data;
+	struct snd_compr_runtime *runtime = stream->runtime;
+	struct fsl_asrc_pair *pair = runtime->private_data;
+
+	/* Stop & release pair/context */
+	if (asrc->m2m_stop)
+		asrc->m2m_stop(pair);
+
+	if (asrc->m2m_unprepare)
+		asrc->m2m_unprepare(pair);
+	asrc->release_pair(pair);
+
+	/* Release dma channel */
+	if (pair->dma_chan[IN])
+		dma_release_channel(pair->dma_chan[IN]);
+	if (pair->dma_chan[OUT])
+		dma_release_channel(pair->dma_chan[OUT]);
+
+	return 0;
+}
+
+static int fsl_asrc_m2m_get_caps(struct snd_compr_stream *cstream,
+				 struct snd_compr_caps *caps)
+{
+	caps->num_codecs = 1;
+	caps->min_fragment_size = 4096;
+	caps->max_fragment_size = 4096;
+	caps->min_fragments = 1;
+	caps->max_fragments = 1;
+	caps->codecs[0] = SND_AUDIOCODEC_PCM;
+
+	return 0;
+}
+
+static int fsl_asrc_m2m_fill_codec_caps(struct fsl_asrc *asrc,
+					struct snd_compr_codec_caps *codec)
+{
+	struct fsl_asrc_m2m_cap cap;
+	snd_pcm_format_t k;
+	int j = 0;
+	int ret;
+
+	ret = asrc->m2m_get_cap(&cap);
+	if (ret)
+		return -EINVAL;
+
+	pcm_for_each_format(k) {
+		if (pcm_format_to_bits(k) & cap.fmt_in) {
+			codec->descriptor[j].max_ch = cap.chan_max;
+			memcpy(codec->descriptor[j].sample_rates,
+			       cap.rate_in,
+			       cap.rate_in_count * sizeof(__u32));
+			codec->descriptor[j].num_sample_rates = cap.rate_in_count;
+			codec->descriptor[j].formats = k;
+			codec->descriptor[j].pcm_formats = cap.fmt_out;
+			codec->descriptor[j].src.out_sample_rate_min = cap.rate_out[0];
+			codec->descriptor[j].src.out_sample_rate_max =
+				cap.rate_out[cap.rate_out_count - 1];
+			j++;
+		}
+	}
+
+	codec->codec = SND_AUDIOCODEC_PCM;
+	codec->num_descriptors = j;
+	return 0;
+}
+
+static int fsl_asrc_m2m_get_codec_caps(struct snd_compr_stream *stream,
+				       struct snd_compr_codec_caps *codec)
+{
+	struct fsl_asrc *asrc = stream->private_data;
+
+	return fsl_asrc_m2m_fill_codec_caps(asrc, codec);
+}
+
+static struct snd_compr_ops fsl_asrc_m2m_compr_ops = {
+	.open = fsl_asrc_m2m_comp_open,
+	.free = fsl_asrc_m2m_comp_release,
+	.set_params = fsl_asrc_m2m_comp_set_params,
+	.get_caps = fsl_asrc_m2m_get_caps,
+	.get_codec_caps = fsl_asrc_m2m_get_codec_caps,
+	.task_create = fsl_asrc_m2m_comp_task_create,
+	.task_start = fsl_asrc_m2m_comp_task_start,
+	.task_stop = fsl_asrc_m2m_comp_task_stop,
+	.task_free = fsl_asrc_m2m_comp_task_free,
+};
+
+int fsl_asrc_m2m_suspend(struct fsl_asrc *asrc)
+{
+	struct fsl_asrc_pair *pair;
+	int i;
+
+	for (i = 0; i < PAIR_CTX_NUM; i++) {
+		pair = asrc->pair[i];
+		if (!pair)
+			continue;
+		if (!completion_done(&pair->complete[IN])) {
+			if (pair->dma_chan[IN])
+				dmaengine_terminate_all(pair->dma_chan[IN]);
+			asrc_input_dma_callback((void *)pair);
+		}
+		if (!completion_done(&pair->complete[OUT])) {
+			if (pair->dma_chan[OUT])
+				dmaengine_terminate_all(pair->dma_chan[OUT]);
+			asrc_output_dma_callback((void *)pair);
+		}
+
+		if (asrc->m2m_pair_suspend)
+			asrc->m2m_pair_suspend(pair);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fsl_asrc_m2m_suspend);
+
+int fsl_asrc_m2m_resume(struct fsl_asrc *asrc)
+{
+	struct fsl_asrc_pair *pair;
+	int i;
+
+	for (i = 0; i < PAIR_CTX_NUM; i++) {
+		pair = asrc->pair[i];
+		if (!pair)
+			continue;
+		if (asrc->m2m_pair_resume)
+			asrc->m2m_pair_resume(pair);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fsl_asrc_m2m_resume);
+
+int fsl_asrc_m2m_init(struct fsl_asrc *asrc)
+{
+	struct device *dev = &asrc->pdev->dev;
+	struct snd_card *card;
+	struct snd_compr *compr;
+	int ret;
+
+	ret = snd_card_new(dev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
+			   THIS_MODULE, 0, &card);
+	if (ret < 0)
+		return ret;
+
+	strscpy(card->driver, "fsl-asrc-m2m", sizeof(card->driver));
+	strscpy(card->shortname, "ASRC-M2M", sizeof(card->shortname));
+	strscpy(card->longname, "ASRC-M2M", sizeof(card->shortname));
+
+	asrc->card = card;
+
+	compr = devm_kzalloc(dev, sizeof(*compr), GFP_KERNEL);
+	if (!compr) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	compr->ops = &fsl_asrc_m2m_compr_ops;
+	compr->private_data = asrc;
+
+	ret = snd_compress_new(card, 0, SND_COMPRESS_ACCEL, "ASRC M2M", compr);
+	if (ret < 0)
+		goto err;
+
+	ret = snd_card_register(card);
+	if (ret < 0)
+		goto err;
+
+	return 0;
+err:
+	snd_card_free(card);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(fsl_asrc_m2m_init);
+
+void fsl_asrc_m2m_exit(struct fsl_asrc *asrc)
+{
+	struct snd_card *card = asrc->card;
+
+	snd_card_free(card);
+}
+EXPORT_SYMBOL_GPL(fsl_asrc_m2m_exit);
+
+MODULE_IMPORT_NS("DMA_BUF");
+MODULE_AUTHOR("Shengjiu Wang <[e-mail]>");
+MODULE_DESCRIPTION("Freescale ASRC M2M driver");
+MODULE_LICENSE("GPL");

sound/soc/fsl/fsl_easrc.c

···
 	return REG_EASRC_FIFO(dir, index);
 }
 
+/* Get sample numbers in FIFO */
+static unsigned int fsl_easrc_get_output_fifo_size(struct fsl_asrc_pair *pair)
+{
+	struct fsl_asrc *asrc = pair->asrc;
+	enum asrc_pair_index index = pair->index;
+	u32 val;
+
+	regmap_read(asrc->regmap, REG_EASRC_SFS(index), &val);
+	val &= EASRC_SFS_NSGO_MASK;
+
+	return val >> EASRC_SFS_NSGO_SHIFT;
+}
+
+static int fsl_easrc_m2m_prepare(struct fsl_asrc_pair *pair)
+{
+	struct fsl_easrc_ctx_priv *ctx_priv = pair->private;
+	struct fsl_asrc *asrc = pair->asrc;
+	struct device *dev = &asrc->pdev->dev;
+	int ret;
+
+	ctx_priv->in_params.sample_rate = pair->rate[IN];
+	ctx_priv->in_params.sample_format = pair->sample_format[IN];
+	ctx_priv->out_params.sample_rate = pair->rate[OUT];
+	ctx_priv->out_params.sample_format = pair->sample_format[OUT];
+
+	ctx_priv->in_params.fifo_wtmk = FSL_EASRC_INPUTFIFO_WML;
+	ctx_priv->out_params.fifo_wtmk = FSL_EASRC_OUTPUTFIFO_WML;
+	/* Fill the right half of the re-sampler with zeros */
+	ctx_priv->rs_init_mode = 0x2;
+	/* Zero fill the right half of the prefilter */
+	ctx_priv->pf_init_mode = 0x2;
+
+	ret = fsl_easrc_set_ctx_format(pair,
+				       &ctx_priv->in_params.sample_format,
+				       &ctx_priv->out_params.sample_format);
+	if (ret) {
+		dev_err(dev, "failed to set context format: %d\n", ret);
+		return ret;
+	}
+
+	ret = fsl_easrc_config_context(asrc, pair->index);
+	if (ret) {
+		dev_err(dev, "failed to config context %d\n", ret);
+		return ret;
+	}
+
+	ctx_priv->in_params.iterations = 1;
+	ctx_priv->in_params.group_len = pair->channels;
+	ctx_priv->in_params.access_len = pair->channels;
+	ctx_priv->out_params.iterations = 1;
+	ctx_priv->out_params.group_len = pair->channels;
+	ctx_priv->out_params.access_len = pair->channels;
+
+	ret = fsl_easrc_set_ctx_organziation(pair);
+	if (ret) {
+		dev_err(dev, "failed to set fifo organization\n");
+		return ret;
+	}
+
+	/* The context start flag */
+	pair->first_convert = 1;
+	return 0;
+}
+
+static int fsl_easrc_m2m_start(struct fsl_asrc_pair *pair)
+{
+	/* start context once */
+	if (pair->first_convert) {
+		fsl_easrc_start_context(pair);
+		pair->first_convert = 0;
+	}
+
+	return 0;
+}
+
+static int fsl_easrc_m2m_stop(struct fsl_asrc_pair *pair)
+{
+	/* Stop pair/context */
+	if (!pair->first_convert) {
+		fsl_easrc_stop_context(pair);
+		pair->first_convert = 1;
+	}
+
+	return 0;
+}
+
+/* calculate capture data length according to output data length and sample rate */
+static int fsl_easrc_m2m_calc_out_len(struct fsl_asrc_pair *pair, int input_buffer_length)
+{
+	struct fsl_asrc *easrc = pair->asrc;
+	struct fsl_easrc_priv *easrc_priv = easrc->private;
+	struct fsl_easrc_ctx_priv *ctx_priv = pair->private;
+	unsigned int in_rate = ctx_priv->in_params.norm_rate;
+	unsigned int out_rate = ctx_priv->out_params.norm_rate;
+	unsigned int channels = pair->channels;
+	unsigned int in_samples, out_samples;
+	unsigned int in_width, out_width;
+	unsigned int out_length;
+	unsigned int frac_bits;
+	u64 val1, val2;
+
+	switch (easrc_priv->rs_num_taps) {
+	case EASRC_RS_32_TAPS:
+		/* integer bits = 5; */
+		frac_bits = 39;
+		break;
+	case EASRC_RS_64_TAPS:
+		/* integer bits = 6; */
+		frac_bits = 38;
+		break;
+	case EASRC_RS_128_TAPS:
+		/* integer bits = 7; */
+		frac_bits = 37;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	val1 = (u64)in_rate << frac_bits;
+	do_div(val1, out_rate);
+	val1 += (s64)ctx_priv->ratio_mod << (frac_bits - 31);
+
+	in_width = snd_pcm_format_physical_width(ctx_priv->in_params.sample_format) / 8;
+	out_width = snd_pcm_format_physical_width(ctx_priv->out_params.sample_format) / 8;
+
+	ctx_priv->in_filled_len += input_buffer_length;
+	if (ctx_priv->in_filled_len <= ctx_priv->in_filled_sample * in_width * channels) {
+		out_length = 0;
+	} else {
+		in_samples = ctx_priv->in_filled_len / (in_width * channels) -
+			     ctx_priv->in_filled_sample;
+
+		/* right shift 12 bit to make ratio in 32bit space */
+		val2 = (u64)in_samples << (frac_bits - 12);
+		val1 = val1 >> 12;
+		do_div(val2, val1);
+		out_samples = val2;
+
+		out_length = out_samples * out_width * channels;
+		ctx_priv->in_filled_len = ctx_priv->in_filled_sample * in_width * channels;
+	}
+
+	return out_length;
+}
+
+static int fsl_easrc_m2m_get_maxburst(u8 dir, struct fsl_asrc_pair *pair)
+{
+	struct fsl_easrc_ctx_priv *ctx_priv = pair->private;
+
+	if (dir == IN)
+		return ctx_priv->in_params.fifo_wtmk * pair->channels;
+	else
+		return ctx_priv->out_params.fifo_wtmk * pair->channels;
+}
+
+static int fsl_easrc_m2m_pair_suspend(struct fsl_asrc_pair *pair)
+{
+	fsl_easrc_stop_context(pair);
+
+	return 0;
+}
+
+static int fsl_easrc_m2m_pair_resume(struct fsl_asrc_pair *pair)
+{
+	struct fsl_easrc_ctx_priv *ctx_priv = pair->private;
+
+	pair->first_convert = 1;
+	ctx_priv->in_filled_len = 0;
+
+	return 0;
+}
+
+/* val is Q31 */
+static int fsl_easrc_m2m_set_ratio_mod(struct fsl_asrc_pair *pair, int val)
+{
+	struct fsl_easrc_ctx_priv *ctx_priv = pair->private;
+	struct fsl_asrc *easrc = pair->asrc;
+	struct fsl_easrc_priv *easrc_priv = easrc->private;
+	unsigned int frac_bits;
+
+	ctx_priv->ratio_mod += val;
+
+	switch (easrc_priv->rs_num_taps) {
+	case EASRC_RS_32_TAPS:
+		/* integer bits = 5; */
+		frac_bits = 39;
+		break;
+	case EASRC_RS_64_TAPS:
+		/* integer bits = 6; */
+		frac_bits = 38;
+		break;
+	case EASRC_RS_128_TAPS:
+		/* integer bits = 7; */
+		frac_bits = 37;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	val <<= (frac_bits - 31);
+	regmap_write(easrc->regmap, REG_EASRC_RUC(pair->index), EASRC_RSUC_RS_RM(val));
+
+	return 0;
+}
+
+static int fsl_easrc_m2m_get_cap(struct fsl_asrc_m2m_cap *cap)
+{
+	cap->fmt_in = FSL_EASRC_FORMATS;
+	cap->fmt_out = FSL_EASRC_FORMATS | SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE;
+	cap->rate_in = easrc_rates;
+	cap->rate_in_count = ARRAY_SIZE(easrc_rates);
+	cap->rate_out = easrc_rates;
+	cap->rate_out_count = ARRAY_SIZE(easrc_rates);
+	cap->chan_min = 1;
+	cap->chan_max = 32;
+	return 0;
+}
+
 static const struct of_device_id fsl_easrc_dt_ids[] = {
 	{ .compatible = "fsl,imx8mn-easrc",},
 	{}
···
 	easrc->release_pair = fsl_easrc_release_context;
 	easrc->get_fifo_addr = fsl_easrc_get_fifo_addr;
 	easrc->pair_priv_size = sizeof(struct fsl_easrc_ctx_priv);
+	easrc->m2m_prepare = fsl_easrc_m2m_prepare;
+	easrc->m2m_start = fsl_easrc_m2m_start;
+	easrc->m2m_stop = fsl_easrc_m2m_stop;
+	easrc->get_output_fifo_size = fsl_easrc_get_output_fifo_size;
+	easrc->m2m_calc_out_len = fsl_easrc_m2m_calc_out_len;
+	easrc->m2m_get_maxburst = fsl_easrc_m2m_get_maxburst;
+	easrc->m2m_pair_suspend = fsl_easrc_m2m_pair_suspend;
+	easrc->m2m_pair_resume = fsl_easrc_m2m_pair_resume;
+	easrc->m2m_set_ratio_mod = fsl_easrc_m2m_set_ratio_mod;
+	easrc->m2m_get_cap = fsl_easrc_m2m_get_cap;
 
 	easrc_priv->rs_num_taps = EASRC_RS_32_TAPS;
 	easrc_priv->const_coeff = 0x3FF0000000000000;
···
 		goto err_pm_disable;
 	}
 
+	ret = fsl_asrc_m2m_init(easrc);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to init m2m device %d\n", ret);
+		return ret;
+	}
+
 	return 0;
 
 err_pm_disable:
···
 
 static void fsl_easrc_remove(struct platform_device *pdev)
 {
+	struct fsl_asrc *easrc = dev_get_drvdata(&pdev->dev);
+
+	fsl_asrc_m2m_exit(easrc);
+
 	pm_runtime_disable(&pdev->dev);
 }
 
···
 	return ret;
 }
 
+static int fsl_easrc_suspend(struct device *dev)
+{
+	struct fsl_asrc *easrc = dev_get_drvdata(dev);
+	int ret;
+
+	fsl_asrc_m2m_suspend(easrc);
+	ret = pm_runtime_force_suspend(dev);
+	return ret;
+}
+
+static int fsl_easrc_resume(struct device *dev)
+{
+	struct fsl_asrc *easrc = dev_get_drvdata(dev);
+	int ret;
+
+	ret = pm_runtime_force_resume(dev);
+	fsl_asrc_m2m_resume(easrc);
+	return ret;
+}
+
 static const struct dev_pm_ops fsl_easrc_pm_ops = {
 	RUNTIME_PM_OPS(fsl_easrc_runtime_suspend, fsl_easrc_runtime_resume, NULL)
-	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
-				pm_runtime_force_resume)
+	SYSTEM_SLEEP_PM_OPS(fsl_easrc_suspend, fsl_easrc_resume)
 };
 
 static struct platform_driver fsl_easrc_driver = {

sound/soc/fsl/fsl_easrc.h

···
  * @out_missed_sample: sample missed in output
  * @st1_addexp: exponent added for stage1
  * @st2_addexp: exponent added for stage2
+ * @ratio_mod: update ratio
+ * @in_filled_len: input filled length
  */
 struct fsl_easrc_ctx_priv {
 	struct fsl_easrc_io_params in_params;
···
 	int out_missed_sample;
 	int st1_addexp;
 	int st2_addexp;
+	int ratio_mod;
+	unsigned int in_filled_len;
 };
 
 /**