// SPDX-License-Identifier: GPL-2.0-or-later
/*
*  Support for Digigram AlpX PCI-e boards
*
*  Copyright (c) 2024 Digigram Digital (info@digigram.com)
*/

#include <linux/version.h>

#include "alpx_reg.h"
#include "alpx.h"
#include "alpx_streams.h"
#include "alpx_led.h"

#include <sound/asound.h>
#include <sound/core.h>
#include <linux/io.h>


extern unsigned int log_transfers; //defined in alpx_core.c

#if !IS_ENABLED(CONFIG_SND_DMAENGINE_PCM)
	#if defined (CONFIG_KERNEL_GENERIC)
		#if KERNEL_VERSION(5, 17, 0) <= LINUX_VERSION_CODE
			#include "core/generic/5.17/dmaengine_pcm.h"
			#include "core/generic/5.17/pcm_dmaengine.c"
		#elif KERNEL_VERSION(5, 12, 0) <= LINUX_VERSION_CODE
			#include "core/generic/5.12/dmaengine_pcm.h"
			#include "core/generic/5.12/pcm_dmaengine.c"
		#elif KERNEL_VERSION(5, 7, 0) <= LINUX_VERSION_CODE
			#include "core/generic/5.7/dmaengine_pcm.h"
			#include "core/generic/5.7/pcm_dmaengine.c"
		#elif KERNEL_VERSION(5, 5, 0) <= LINUX_VERSION_CODE
			#include "core/generic/5.5/dmaengine_pcm.h"
			#include "core/generic/5.5/pcm_dmaengine.c"
		#elif KERNEL_VERSION(5, 2, 0) <= LINUX_VERSION_CODE
			#include "core/generic/5.2/dmaengine_pcm.h"
			#include "core/generic/5.2/pcm_dmaengine.c"
		#elif KERNEL_VERSION(4, 19, 0) <= LINUX_VERSION_CODE
			#include "core/generic/4.19/dmaengine_pcm.h"
			#include "core/generic/4.19/pcm_dmaengine.c"
		#endif
	#elif defined (CONFIG_KERNEL_REDHAT)
		#if KERNEL_VERSION(5, 14, 0) <= LINUX_VERSION_CODE
			#include "core/RedHat/5.14/dmaengine_pcm.h"
			#include "core/RedHat/5.14/pcm_dmaengine.c"
		#elif KERNEL_VERSION(4, 18, 0) == LINUX_VERSION_CODE
			#include "core/RedHat/4.18/dmaengine_pcm.h"
			#include "core/RedHat/4.18/pcm_dmaengine.c"
		#else
			#error RedHat kernel not supported yet.
		#endif
	#endif
#elif defined (CONFIG_KERNEL_GENERIC)
	#include <sound/dmaengine_pcm.h>
#else
	#error "No valid DMA Engine support!"
#endif

/* The size (in bytes) of sample's container */
const unsigned int ALPX_SAMPLE_CONTAINER_SIZE = 4;


/* Configure */

static int alpmadi_configure(struct alpx_device *alpx_dev, unsigned int rate)
{
	u32 config_fs, value;

	dev_dbg(alpx_dev->dev, "%s(): requesting rate %d\n", __func__, rate);

	switch (rate) {
	case 44100:
	config_fs = ALPMADI_CLK_MANAGER_CONFIG_FS_44_1K;
		break;
	case 48000:
		config_fs = ALPMADI_CLK_MANAGER_CONFIG_FS_48K;
		break;
	case 88200:
		config_fs = ALPMADI_CLK_MANAGER_CONFIG_FS_88_2K;
		break;
	case 96000:
		config_fs = ALPMADI_CLK_MANAGER_CONFIG_FS_96K;
		break;
	case 176400:
		config_fs = ALPMADI_CLK_MANAGER_CONFIG_FS_176_4K;
		break;
	case 192000:
		config_fs = ALPMADI_CLK_MANAGER_CONFIG_FS_192K;
		break;
	default:
		return -EINVAL;
	}

	value = readl(ALPX_REG(alpx_dev, ALPMADI, CLK_MANAGER, CONFIG));
	dev_dbg(alpx_dev->dev, "%s(): alpMadi clk manager config %x\n", __func__, value);

	value &= ~ALPMADI_CLK_MANAGER_CONFIG_FS_MASK;
	value |= config_fs;

	writel(value, ALPX_REG(alpx_dev, ALPMADI, CLK_MANAGER, CONFIG));
	dev_dbg(alpx_dev->dev, "%s(): alpMadi clk manager set to %x\n", __func__, value);

	return 0;
}

static int alpdante_configure(struct alpx_device *alpx_dev, unsigned int rate)
{
	dev_dbg(alpx_dev->dev, "%s(): requesting rate %dHz\n", __func__, rate);
	
	if (alpx_dev->variant->capture_hw->rate_min == rate) {
		dev_dbg(alpx_dev->dev, "%s(): requested rate %dHz is supported\n", __func__, rate);
		return 0;
	}
	else {
		dev_dbg(alpx_dev->dev, "Requested %dHz not supported, Currently supported rate is %dHz\n", rate, 
				alpx_dev->variant->capture_hw->rate_min);
		return -EINVAL;
	}
	
}

static int alpstereo_configure(struct alpx_device *alpx_dev, unsigned int rate)
{
	u32 config_fs, read_value, target_value;
	u32 try_qty = 10; /* retries */

	dev_dbg(alpx_dev->dev, "%s(): requesting rate %d\n", __func__, rate);

	switch (rate) {
	case 8000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_8K;
		break;
	case 11025:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_11_025K;
		break;
	case 16000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_16K;
		break;
	case 22000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_22_05K;
		break;
	case 24000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_24K;
		break;
	case 32000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_32K;
		break;
	case 44100:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_44_1K;
		break;
	case 48000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_48K;
		break;
	case 64000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_64K;
		break;		
	case 88200:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_88_2K;
		break;
	case 96000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_96K;
		break;
	case 128000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_128K;
		break;
	case 176400:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_176_4K;
		break;
	case 192000:
		config_fs =  ALPxxx_CLK_MANAGER_CLK_VALUE_192K;
		break;
	default:
		return -EINVAL;
	}

	read_value = readl(ALPX_REG(alpx_dev, ALP222, CLK_MANAGER, CONFIG));

	/* Only if needed */
	if ((read_value & ALP222_CLK_MANAGER_CONFIG_FS_MASK) == config_fs)
		return 0;

	read_value &= ~ALP222_CLK_MANAGER_CONFIG_FS_MASK;
	target_value = read_value | config_fs;

	do {
		writel(target_value, ALPX_REG(alpx_dev, ALP222, CLK_MANAGER, CONFIG));
		dev_dbg(alpx_dev->dev, "%s(): alp222 new clk config set to %x try: %d\n",
			__func__, target_value, try_qty);

		/* Add a delay to give time to the card to initialize its
		* internals (PLL, buses,...) to avoid internal stalls.
		*/
		mdelay(1);

		read_value = readl(ALPX_REG(alpx_dev, ALP222, CLK_MANAGER, CONFIG));
		dev_dbg(alpx_dev->dev, "%s(): alp222 check clk config: %x\n", __func__, read_value);
	} while (--try_qty &&
		((read_value & ALP222_CLK_MANAGER_CONFIG_FS_MASK ) !=
		(target_value & ALP222_CLK_MANAGER_CONFIG_FS_MASK)));

	if ((read_value & ALP222_CLK_MANAGER_CONFIG_FS_MASK) !=
		(target_value & ALP222_CLK_MANAGER_CONFIG_FS_MASK))
	dev_err(alpx_dev->dev, "%s(): alp222 ERROR clk config, expected: 0x%x, actual: 0x%x, \n", __func__,
			target_value, read_value);

	dev_dbg(alpx_dev->dev, "%s(): alp222 new current clk config: 0x%x\n", __func__, 
		readl(ALPX_REG(alpx_dev, ALP222, CLK_MANAGER, CONFIG)));
	
	return (read_value & ALP222_CLK_MANAGER_CONFIG_FS_MASK) ==
		(target_value & ALP222_CLK_MANAGER_CONFIG_FS_MASK) ? 0 : -EIO;
}

static int alpmultichannel_configure(struct alpx_device *alpx_dev, unsigned int rate)
{
	u32 config_fs, value;
	u32 effective_fs, source;
	/* XXX: check clock source, if not internal, error out if rate is not
	external one */
	dev_dbg(alpx_dev->dev, "%s(): requesting rate %d\n", __func__, rate);
	
	value = readl(ALPX_REG(alpx_dev, ALPMC, CLK_MANAGER, CONFIG));


	
	source = ALPMC_CLK_MANAGER_SOURCE(value);
	effective_fs = ALPMC_CLK_MANAGER_EFFECTIVE_FS(value);

	switch (rate) {
	case 8000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_8K;
		break;
	case 11025:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_11_025K;
		break;
	case 16000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_16K;
		break;
	case 22050:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_22_05K;
		break;
	case 24000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_24K;
		break;
	case 32000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_32K;
		break;
	case 44100:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_44_1K;
		break;
	case 48000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_48K;
		break;
	case 64000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_64K;
		break;
	case 88200:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_88_2K;
		break;
	case 96000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_96K;
		break;
	case 128000:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_128K;
		break;
	case 176400:
		config_fs = ALPxxx_CLK_MANAGER_CLK_VALUE_176_4K;
		break;
	case 192000:
		config_fs =  ALPxxx_CLK_MANAGER_CLK_VALUE_192K;
		break;
	default:
		return -EINVAL;
	}

	if (source != ALPMC_CLK_MANAGER_SOURCE_INTERNAL) {
		unsigned int effective_rate;

		switch(effective_fs) {
		case ALPxxx_CLK_MANAGER_CLK_VALUE_8K :
			effective_rate = 8000;
			break;
		case ALPxxx_CLK_MANAGER_CLK_VALUE_11_025K :
			effective_rate = 11025;
			break;
		case ALPxxx_CLK_MANAGER_CLK_VALUE_16K :
			effective_rate = 16000;
			break;
		case ALPxxx_CLK_MANAGER_CLK_VALUE_22_05K :
			effective_rate = 22050;
			break;
		case ALPxxx_CLK_MANAGER_CLK_VALUE_24K :
			effective_rate = 24000;
			break;
		case ALPxxx_CLK_MANAGER_CLK_VALUE_32K:
			effective_rate = 32000;
			break;
		case ALPxxx_CLK_MANAGER_CLK_VALUE_44_1K:
			effective_rate = 44100;
			break;
		case ALPxxx_CLK_MANAGER_CLK_VALUE_48K :
			effective_rate = 48000;
			break;
		case ALPxxx_CLK_MANAGER_CLK_VALUE_64K :
			effective_rate = 64000;
			break;
		case ALPxxx_CLK_MANAGER_CLK_VALUE_88_2K :
			effective_rate = 88200;
			break;
		case ALPxxx_CLK_MANAGER_CLK_VALUE_96K :
			effective_rate = 96000;
			break;
		case ALPxxx_CLK_MANAGER_CLK_VALUE_128K :
			effective_rate = 128000;
			break;
		case ALPxxx_CLK_MANAGER_CLK_VALUE_176_4K :
			effective_rate = 176400;
			break;
		case ALPxxx_CLK_MANAGER_CLK_VALUE_192K :
			effective_rate = 192000;
			break;
		default :
			dev_err(alpx_dev->dev,
				"Invalid effective sample rate\n");
			return -EINVAL;
		};

		if (effective_rate != rate) {
			dev_err(alpx_dev->dev,
				"Requested sample rate (%u) does not match external clock sample rate (%u)\n",
				rate, effective_rate);
			return -EINVAL;
		}
	} else {
		if (ALPMC_CLK_MANAGER_CONFIG_FS(value) != config_fs) {
		
			value &= ~ALPMC_CLK_MANAGER_CONFIG_FS_MASK;
			value |= config_fs;

			writel(value, ALPX_REG(alpx_dev, ALPMC, CLK_MANAGER, CONFIG));
			//Add a delay to give time to the card (PLL, internal buses,...), w/o, the setting is not effective  !
			mdelay(ALPMC_FS_SWITCH_DELAY);
		}
	}
	
	dev_dbg(alpx_dev->dev, "%s() : %s  new current clk config: 0x%x\n", __func__, 
			alpx_dev->variant->shortname,
			readl(ALPX_REG(alpx_dev, ALPMC, CLK_MANAGER, CONFIG)));

	return 0;
}

static int alpx_configure(struct alpx_device *alpx_dev, unsigned int rate)
{
	unsigned long flags;
	int ret = 0;

	spin_lock_irqsave(&alpx_dev->config.lock, flags);

	if (alpx_dev->config.users > 0 && rate != alpx_dev->config.rate) {
		ret = -EINVAL;
		goto complete;
	}

	alpx_dev->config.rate = rate;

	if (alpx_is_882(alpx_dev))
		ret = alpmultichannel_configure(alpx_dev, rate);
	else if (alpx_is_222(alpx_dev))
		ret = alpstereo_configure(alpx_dev, rate);
	else if (alpx_is_madi(alpx_dev))
		ret = alpmadi_configure(alpx_dev, rate);
	else if (alpx_is_dante(alpx_dev))
		ret = alpdante_configure(alpx_dev, rate);
	else
		snd_BUG();

	if (!ret)
		alpx_dev->config.users++;

complete:
	spin_unlock_irqrestore(&alpx_dev->config.lock, flags);

	return ret;
}

static void alpx_configure_close(struct alpx_device *alpx_dev)
{
	unsigned long flags;

	spin_lock_irqsave(&alpx_dev->config.lock, flags);

	alpx_dev->config.users--;

	spin_unlock_irqrestore(&alpx_dev->config.lock, flags);
}

/* Pipe */

static int alpx_pipe_start(struct alpx_pipe *pipe, struct snd_pcm_substream *substream)
{
	struct alpx_device *alpx_dev = snd_pcm_substream_chip(substream);

	dev_dbg( alpx_dev->dev, "%s starting\n", pipe->xdma_write ? "Playback" : "Capture");

	if (pipe->status != ALPX_PIPE_STATUS_IDLE &&
		pipe->status != ALPX_PIPE_STATUS_STOPPED) {
		dev_warn(alpx_dev->dev, "%s pipe is busy!\n",
			pipe->xdma_write ? "playback" : "capture");
		return -EBUSY;
	}

	if (alpx_is_madi(alpx_dev))
		alpmadi_set_led_state(alpx_dev, true);

	snd_dmaengine_pcm_trigger(substream, SNDRV_PCM_TRIGGER_START);
	pipe->period_qty_on_start = alpx_get_samples_counter(alpx_dev);

	dev_dbg( alpx_dev->dev, "%s Period:%u\n", pipe->xdma_write ? "Playback" : "Capture", pipe->period_qty_on_start);

	return 0;
}

static int alpx_pipe_open(struct alpx_pipe *pipe,
			struct snd_pcm_substream *substream)
{
	struct alpx_device *alpx_dev = substream->pcm->private_data;
	struct dma_chan *chan;

	/* Check */
	if (!alpx_dev) {
		printk(KERN_ERR"%s() :  alpx_dev is NULL\n",__func__);
		return -EINVAL;
	}

	if (!alpx_dev->dev) {
		printk(KERN_ERR"%s() :  alpx_dev->dev is NULL\n",__func__);
		return -EINVAL;
	}

	dev_dbg(alpx_dev->dev, "%s(): CALLED\n", __func__);

	dev_dbg(alpx_dev->dev, "%s: matching with dev [%s]\n", __func__, dev_name(alpx_dev->dev));

	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
		chan = dma_request_chan(alpx_dev->dev, "h2c-0");
	else
		chan = dma_request_chan(alpx_dev->dev, "c2h-0");

	if (IS_ERR(chan)) {
		dev_err(alpx_dev->dev, "%s() : Error %ld when requesting DMA channel\n",
			__func__, PTR_ERR(chan));
		return PTR_ERR(chan);
	}

	pipe->substream = substream;

	return snd_dmaengine_pcm_open(substream, chan);

}

static int alpx_pipe_stop(struct alpx_pipe *pipe, struct snd_pcm_substream *substream)
{
	struct alpx_device *alpx_dev = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	unsigned int samples_counter, card_samples_qty;

	/* Retrieve the samples counter as soon as possible */
	samples_counter = alpx_get_samples_counter(alpx_dev);
	snd_dmaengine_pcm_trigger(substream, SNDRV_PCM_TRIGGER_STOP);

	if (alpx_is_madi(alpx_dev))
		alpmadi_set_led_state(alpx_dev, false);

	/*
	* Since we are under stream lock here and the transfer done callback
	* also needs to grab stream lock, we cannot have a sync wait for the
	* completion. As a result, we request a stop with the stopping status.
	*/
	card_samples_qty = samples_counter - pipe->period_qty_on_start;
	dev_dbg(alpx_dev->dev, "%s stopped after %u samples (%u bytes)\n",
		pipe->xdma_write ? "Playback" : "Capture", card_samples_qty,
		runtime->hw.channels_max * ALPX_SAMPLE_CONTAINER_SIZE * card_samples_qty);

	if (pipe->status == ALPX_PIPE_STATUS_RUNNING)
		pipe->status = ALPX_PIPE_STATUS_STOPPING;
	else
		pipe->status = ALPX_PIPE_STATUS_STOPPED;

	return 0;
}

static int alpx_pipe_configure(struct alpx_pipe *pipe,
				struct snd_pcm_hw_params *hw_params)
{
	struct alpx_device *alpx_dev = pipe->substream->pcm->private_data;
	unsigned int rate = params_rate(hw_params);
	int ret;

	dev_dbg(alpx_dev->dev, "%s hardware parameters:\n",
		pipe->substream->stream == SNDRV_PCM_STREAM_PLAYBACK ? "Playback" : "Capture");
	dev_dbg(alpx_dev->dev, "* channels: %d\n", params_channels(hw_params));
	dev_dbg(alpx_dev->dev, "* rate: %d\n", params_rate(hw_params));
	dev_dbg(alpx_dev->dev, "* periods: %d\n", params_periods(hw_params));
	dev_dbg(alpx_dev->dev, "* period size: %d frames\n",
		params_period_size(hw_params));
	dev_dbg(alpx_dev->dev, "* period bytes: %d bytes\n",
		params_period_size(hw_params) * params_channels(hw_params) * 4);
	dev_dbg(alpx_dev->dev, "* buffer size: %d frames\n",
		params_buffer_size(hw_params));
	dev_dbg(alpx_dev->dev, "* buffer bytes: %d bytes\n",
		params_buffer_bytes(hw_params));

	ret = alpx_configure(alpx_dev, rate);
	if (ret)
		return ret;

	pipe->configured = true;

	return 0;
}

static void alpx_pipe_close(struct alpx_pipe *pipe)
{
	struct alpx_device *alpx_dev = pipe->substream->pcm->private_data;

	dev_dbg(alpx_dev->dev, "%s(): CALLED\n", __func__);

	snd_dmaengine_pcm_close_release_chan(pipe->substream);

	if (pipe->configured) {
		alpx_configure_close(alpx_dev);
		pipe->configured = false;
	}
}

int alpx_pipe_init(struct alpx_pipe *pipe, bool xdma_write)
{
	pipe->xdma_write = xdma_write;

	pipe->status = ALPX_PIPE_STATUS_IDLE;

	return 0;
}

/* Playback */

int alpx_playback_open(struct snd_pcm_substream *substream)
{
	struct alpx_device *alpx_dev = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	int ret;

	//Add a break to avoid playback lock when chaining playbacks. This is required for AlpDANTE cards. Looks like the XDMA needs some time here.
	msleep(200);

	dev_dbg(alpx_dev->dev, "CALLED\n");

	ret = alpx_pipe_open(&alpx_dev->playback, substream);
	if (!ret)
		runtime->hw = *alpx_dev->variant->playback_hw;

	dev_dbg(alpx_dev->dev, "=> %u\n", ret);
	return ret;
}

int alpx_playback_close(struct snd_pcm_substream *substream)
{
	struct alpx_device *alpx_dev = snd_pcm_substream_chip(substream);

	alpx_pipe_close(&alpx_dev->playback);
	return 0;
}

int alpx_playback_hw_params(struct snd_pcm_substream *substream,
				struct snd_pcm_hw_params *hw_params)
{
	struct alpx_device *alpx_dev = snd_pcm_substream_chip(substream);
	int ret;

	ret = alpx_pipe_configure(&alpx_dev->playback, hw_params);
	if (ret)
		return ret;

#if KERNEL_VERSION(5, 5, 0) <= LINUX_VERSION_CODE
	return 0;
#else
	return snd_pcm_lib_malloc_pages(substream,
					params_buffer_bytes(hw_params));
#endif
}

int alpx_playback_hw_free(struct snd_pcm_substream *substream)
{

#if KERNEL_VERSION(5, 5, 0) <= LINUX_VERSION_CODE
	return 0;
#else
	return snd_pcm_lib_free_pages(substream);
#endif
}

int alpx_playback_prepare(struct snd_pcm_substream *substream)
{
	return 0;
}

int alpx_playback_trigger(struct snd_pcm_substream *substream,
				int command)
{
	struct alpx_device *alpx_dev = snd_pcm_substream_chip(substream);

	dev_dbg(alpx_dev->dev, "CALLED\n");

	switch (command) {
	case SNDRV_PCM_TRIGGER_START:
		alpx_pipe_start(&alpx_dev->playback, substream);
		break;
	case SNDRV_PCM_TRIGGER_STOP:
		alpx_pipe_stop(&alpx_dev->playback, substream);
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

const struct snd_pcm_ops alpx_playback_ops = {
	.open		= alpx_playback_open,
	.close		= alpx_playback_close,
#if KERNEL_VERSION(5, 6, 0) > LINUX_VERSION_CODE
	.ioctl		= snd_pcm_lib_ioctl,
#endif
	.hw_params	= alpx_playback_hw_params,
	.hw_free	= alpx_playback_hw_free,
	.prepare	= alpx_playback_prepare,
	.trigger	= alpx_playback_trigger,
	.pointer	= snd_dmaengine_pcm_pointer,
};

/* Capture */

int alpx_capture_open(struct snd_pcm_substream *substream)
{
	struct alpx_device *alpx_dev = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	int ret;

	ret = alpx_pipe_open(&alpx_dev->capture, substream);
	if (ret)
		return ret;

	runtime->hw = *alpx_dev->variant->capture_hw;

	return 0;
}

int alpx_capture_close(struct snd_pcm_substream *substream)
{
	struct alpx_device *alpx_dev = snd_pcm_substream_chip(substream);

	alpx_pipe_close(&alpx_dev->capture);

	return 0;
}

int alpx_capture_hw_params(struct snd_pcm_substream *substream,
				struct snd_pcm_hw_params *hw_params)
{
	struct alpx_device *alpx_dev = snd_pcm_substream_chip(substream);
	int ret;

	ret = alpx_pipe_configure(&alpx_dev->capture, hw_params);
	if (ret)
		return ret;

#if KERNEL_VERSION(5, 5, 0) <= LINUX_VERSION_CODE
	return 0;
#else
	return snd_pcm_lib_malloc_pages(substream,
					params_buffer_bytes(hw_params));
#endif
}

int alpx_capture_hw_free(struct snd_pcm_substream *substream)
{
#if KERNEL_VERSION(5, 5, 0) <= LINUX_VERSION_CODE
	return 0;
#else
	return snd_pcm_lib_free_pages(substream);
#endif
}

int alpx_capture_prepare(struct snd_pcm_substream *substream)
{
	return 0;
}

int alpx_capture_trigger(struct snd_pcm_substream *substream,
				int command)
{
	struct alpx_device *alpx_dev = snd_pcm_substream_chip(substream);

	switch (command) {
	case SNDRV_PCM_TRIGGER_START:
		alpx_pipe_start(&alpx_dev->capture, substream);
		break;
	case SNDRV_PCM_TRIGGER_STOP:
		alpx_pipe_stop(&alpx_dev->capture, substream);
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

const struct snd_pcm_ops alpx_capture_ops = {
	.open		= alpx_capture_open,
	.close		= alpx_capture_close,
#if KERNEL_VERSION(5, 6, 0) > LINUX_VERSION_CODE
	.ioctl		= snd_pcm_lib_ioctl,
#endif
	.hw_params	= alpx_capture_hw_params,
	.hw_free	= alpx_capture_hw_free,
	.prepare	= alpx_capture_prepare,
	.trigger	= alpx_capture_trigger,
	.pointer	= snd_dmaengine_pcm_pointer,
};