From 6227286d980d0bb40bb71d76ce0da7900f1f8f6a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?G=C3=A9=20Koerkamp?= <ge.koerkamp@gmail.com>
Date: Fri, 4 Jan 2019 12:08:14 +0100
Subject: [PATCH] USB Audio: improve native DSD playback detection (#5)

---
 sound/usb/card.h   |  1 +
 sound/usb/format.c |  5 ++++-
 sound/usb/quirks.c | 26 +++++++++++++++++++++++++-
 3 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/sound/usb/card.h b/sound/usb/card.h
index bf2889a2..1bb17983 100644
--- a/sound/usb/card.h
+++ b/sound/usb/card.h
@@ -30,6 +30,7 @@ struct audioformat {
 	struct snd_pcm_chmap_elem *chmap; /* (optional) channel map */
 	bool dsd_dop;			/* add DOP headers in case of DSD samples */
 	bool dsd_bitrev;		/* reverse the bits of each DSD sample */
+	bool dsd_raw;			/* altsetting is raw DSD */
 };
 
 struct snd_usb_substream;
diff --git a/sound/usb/format.c b/sound/usb/format.c
index 99299ffb..626d8e26 100644
--- a/sound/usb/format.c
+++ b/sound/usb/format.c
@@ -64,8 +64,11 @@ static u64 parse_audio_format_i_type(struct snd_usb_audio *chip,
 		sample_width = fmt->bBitResolution;
 		sample_bytes = fmt->bSubslotSize;
 
-		if (format & UAC2_FORMAT_TYPE_I_RAW_DATA)
+		if (format & UAC2_FORMAT_TYPE_I_RAW_DATA) {
 			pcm_formats |= SNDRV_PCM_FMTBIT_SPECIAL;
+			/* flag potentially raw DSD capable altsettings */
+			fp->dsd_raw = true;
+		}
 
 		format <<= 1;
 		break;
diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c
index e10a93eb..35dbfe5b 100644
--- a/sound/usb/quirks.c
+++ b/sound/usb/quirks.c
@@ -987,11 +987,13 @@ u64 snd_usb_interface_dsd_format_quirks(struct snd_usb_audio *chip,
 	case USB_ID(0x22d9, 0x0436): /* OPPO Sonica */
 	case USB_ID(0x22d9, 0x0461): /* OPPO UDP-205 */
 	case USB_ID(0x2522, 0x0012): /* LH Labs VI DAC Infinity */
+	case USB_ID(0x2772, 0x0230): /* Pro-Ject Pre Box S2 Digital */
 	case USB_ID(0x25ce, 0x001f): /* Mytek Brooklyn DAC */
 		if (fp->altsetting == 2)
 			return SNDRV_PCM_FMTBIT_DSD_U32_BE;
 		break;
 
+	case USB_ID(0x16d0, 0x09dd): /* Encore mDSD */
 	case USB_ID(0x0d8c, 0x0316): /* Hegel HD12 DSD */
 	case USB_ID(0x16b0, 0x06b2): /* NuPrime DAC-10 */
 	case USB_ID(0x16d0, 0x0733): /* Furutech ADL Stratos */
@@ -1020,7 +1022,10 @@ u64 snd_usb_interface_dsd_format_quirks(struct snd_usb_audio *chip,
 		break;
 
 	/* Amanero Combo384 USB interface with native DSD support */
-	case USB_ID(0x16d0, 0x071a):
+	case USB_ID(0x16d0, 0x071a):  /* Amanero - Combo384 */
+	case USB_ID(0x2ab6, 0x0004):  /* T+A DAC8DSD-V2.0, MP1000E-V2.0, MP2000R-V2.0, MP2500R-V2.0, MP3100HV-V2.0 */
+	case USB_ID(0x2ab6, 0x0005):  /* T+A USB HD Audio 1 */
+	case USB_ID(0x2ab6, 0x0006):  /* T+A USB HD Audio 2 */
 		if (fp->altsetting == 2) {
 		//	switch (chip->dev->descriptor.bcdDevice) {
 			switch (le16_to_cpu(chip->dev->descriptor.bcdDevice)) {
@@ -1033,10 +1038,29 @@ u64 snd_usb_interface_dsd_format_quirks(struct snd_usb_audio *chip,
 			}
 		}
                 break;
+	case USB_ID(0x16d0, 0x0a23):
+		if (fp->altsetting == 2)
+			return SNDRV_PCM_FMTBIT_DSD_U32_BE;
+		break;
 
+	default:
+		break;
+	}
 
+	/* Mostly generic method to detect many DSD-capable implementations -
+	 * from XMOS/Thesycon
+	 */
+	switch (USB_ID_VENDOR(chip->usb_id)) {
+	case 0x20b1:  /* XMOS based devices */
+	case 0x152a:  /* Thesycon devices */
+	case 0x25ce:  /* Mytek devices */
+		if (fp->dsd_raw) {
+			return SNDRV_PCM_FMTBIT_DSD_U32_BE;
+		}
+		break;
 	default:
 		break;
+
 	}
 
 	return 0;