path: root/sound/usb/format.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 */

#include <linux/init.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/usb/audio.h>
#include <linux/usb/audio-v2.h>
#include <linux/usb/audio-v3.h>

#include <sound/core.h>
#include <sound/pcm.h>

#include "usbaudio.h"
#include "card.h"
#include "quirks.h"
#include "helper.h"
#include "clock.h"
#include "format.h"

/*
 * parse the audio format type I descriptor
 * and returns the corresponding pcm format
 *
 * @dev: usb device
 * @fp: audioformat record
 * @format: the format tag (wFormatTag)
 * @fmt: the format type descriptor (v1/v2) or AudioStreaming descriptor (v3)
 */
static u64 parse_audio_format_i_type(struct snd_usb_audio *chip,
				     struct audioformat *fp,
				     u64 format, void *_fmt)
{
	int sample_width, sample_bytes;
	u64 pcm_formats = 0;
	u64 dsd_formats = 0;

	switch (fp->protocol) {
	case UAC_VERSION_1:
	default: {
		struct uac_format_type_i_discrete_descriptor *fmt = _fmt;
		if (format >= 64) {
			usb_audio_info(chip,
				       "%u:%d: invalid format type 0x%llx is detected, processed as PCM\n",
				       fp->iface, fp->altsetting, format);
			format = UAC_FORMAT_TYPE_I_PCM;
		}
		sample_width = fmt->bBitResolution;
		sample_bytes = fmt->bSubframeSize;
		format = 1ULL << format;
		break;
	}

	case UAC_VERSION_2: {
		struct uac_format_type_i_ext_descriptor *fmt = _fmt;
		sample_width = fmt->bBitResolution;
		sample_bytes = fmt->bSubslotSize;

		if (format & UAC2_FORMAT_TYPE_I_RAW_DATA) {
			pcm_formats |= SNDRV_PCM_FMTBIT_SPECIAL;
			/* flag potentially raw DSD capable altsettings */
			fp->dsd_raw = true;
			/* clear special format bit to avoid "unsupported format" msg below */
			format &= ~UAC2_FORMAT_TYPE_I_RAW_DATA;
		}

		format <<= 1;
		break;
	}
	case UAC_VERSION_3: {
		struct uac3_as_header_descriptor *as = _fmt;

		sample_width = as->bBitResolution;
		sample_bytes = as->bSubslotSize;

		if (format & UAC3_FORMAT_TYPE_I_RAW_DATA) {
			pcm_formats |= SNDRV_PCM_FMTBIT_SPECIAL;
			/* clear special format bit to avoid "unsupported format" msg below */
			format &= ~UAC3_FORMAT_TYPE_I_RAW_DATA;
		}

		format <<= 1;
		break;
	}
	}

	fp->fmt_bits = sample_width;
	fp->fmt_sz = sample_bytes;

	if ((pcm_formats == 0) &&
	    (format == 0 || format == BIT(UAC_FORMAT_TYPE_I_UNDEFINED))) {
		/* some devices don't define this correctly... */
		usb_audio_info(chip, "%u:%d : format type 0 is detected, processed as PCM\n",
			fp->iface, fp->altsetting);
		format = BIT(UAC_FORMAT_TYPE_I_PCM);
	}
	if (format & BIT(UAC_FORMAT_TYPE_I_PCM)) {
		if (((chip->usb_id == USB_ID(0x0582, 0x0016)) ||
		     /* Edirol SD-90 */
		     (chip->usb_id == USB_ID(0x0582, 0x000c))) &&
		     /* Roland SC-D70 */
		    sample_width == 24 && sample_bytes == 2)
			sample_bytes = 3;
		else if (sample_width > sample_bytes * 8) {
			usb_audio_info(chip, "%u:%d : sample bitwidth %d in over sample bytes %d\n",
				 fp->iface, fp->altsetting,
				 sample_width, sample_bytes);
		}
		/* check the format byte size */
		switch (sample_bytes) {
		case 1:
			pcm_formats |= SNDRV_PCM_FMTBIT_S8;
			break;
		case 2:
			if (snd_usb_is_big_endian_format(chip, fp))
				pcm_formats |= SNDRV_PCM_FMTBIT_S16_BE; /* grrr, big endian!! */
			else
				pcm_formats |= SNDRV_PCM_FMTBIT_S16_LE;
			break;
		case 3:
			if (snd_usb_is_big_endian_format(chip, fp))
				pcm_formats |= SNDRV_PCM_FMTBIT_S24_3BE; /* grrr, big endian!! */
			else
				pcm_formats |= SNDRV_PCM_FMTBIT_S24_3LE;
			break;
		case 4:
			pcm_formats |= SNDRV_PCM_FMTBIT_S32_LE;
			break;
		default:
			usb_audio_info(chip,
				 "%u:%d : unsupported sample bitwidth %d in %d bytes\n",
				 fp->iface, fp->altsetting,
				 sample_width, sample_bytes);
			break;
		}
	}
	if (format & BIT(UAC_FORMAT_TYPE_I_PCM8)) {
		/* Dallas DS4201 workaround: it advertises U8 format, but really
		   supports S8. */
		if (chip->usb_id == USB_ID(0x04fa, 0x4201))
			pcm_formats |= SNDRV_PCM_FMTBIT_S8;
		else
			pcm_formats |= SNDRV_PCM_FMTBIT_U8;
	}
	if (format & BIT(UAC_FORMAT_TYPE_I_IEEE_FLOAT))
		pcm_formats |= SNDRV_PCM_FMTBIT_FLOAT_LE;
	if (format & BIT(UAC_FORMAT_TYPE_I_ALAW))
		pcm_formats |= SNDRV_PCM_FMTBIT_A_LAW;
	if (format & BIT(UAC_FORMAT_TYPE_I_MULAW))
		pcm_formats |= SNDRV_PCM_FMTBIT_MU_LAW;
	if (format & ~0x3f) {
		usb_audio_info(chip,
			 "%u:%d : unsupported format bits %#llx\n",
			 fp->iface, fp