From: "Ismaïl Bahloul" <i.bahloul01@gmail.com>
To: linux-sound@vger.kernel.org
Cc: linux-usb@vger.kernel.org, alsa-devel@alsa-project.org,
perex@perex.cz, tiwai@suse.com, linux-kernel@vger.kernel.org,
"Ismaïl Bahloul" <i.bahloul01@gmail.com>
Subject: [RFC PATCH 1/1] ALSA: usb: add RME Babyface Pro FS driver (proprietary mode)
Date: Sat, 29 Aug 2026 11:03:33 +0100 [thread overview]
Message-ID: <20260829100333.32933-2-i.bahloul01@gmail.com> (raw)
In-Reply-To: <20260829100333.32933-1-i.bahloul01@gmail.com>
The RME Babyface Pro FS presents two USB personalities: a
class-compliant one already handled by snd-usb-audio, and a
proprietary one (VID 0x2a39, PID 0x3fc0) whose PCM stream runs on
INTERRUPT endpoints (interface 5, ep 0x01 OUT / 0x82 IN) instead of
the class-compliant isochronous path. snd-usb-audio's PCM engine is
isochronous-only and has no interrupt-transfer path, so this mode
cannot be handled as a quirk; it needs a standalone driver, modeled
on snd-usb-caiaq (the existing in-tree precedent for interrupt-based
USB audio streaming).
The proprietary mode is the one worth supporting: it exposes the
full channel count and the hardware DSP mixer that TotalMix FX
drives on Windows/Mac, none of which is reachable in class-compliant
mode. The vendor protocol (control requests, register map, front
panel readback) was reverse-engineered from Windows USB captures and
validated against real hardware; the capture analysis and calibrated
laws are documented alongside the userspace reference implementation
at https://github.com/ismail-bahloul/TuxMix (not part of this
series).
What's included:
- Interrupt-URB PCM streaming, full-duplex, 2-12 channels, S24_LE,
9 sample rates 32-192 kHz across 3 USB bandwidth classes.
- ALSA mixer: 6 output masters + mutes, the 6x14 crosspoint routing
matrix, 4 mic/instrument preamp gains with phantom power and PAD,
pitch/varispeed, loopback, and several device-specific toggles
(AN 1>2, input link, MS processor, DIM, width, FX send).
- Front-panel emulation: the device has no onboard DSP for its own
panel, so the host mirrors TotalMix's role, translating physical
wheel/button events into mixer writes and exposing the decoded
panel state as read-only ALSA controls.
- Hardware 3-band + low-cut parametric EQ (4 analog-input strips),
computed in fixed-point (no FPU use) and uploaded as coefficient
blocks.
- Mixer-state persistence across interface re-probes (a userspace
client can usbfs-claim the interface, silently detaching this
driver) and system suspend/resume, since the device firmware has
no state readback of its own.
Split across two files matching the driver's two natural halves:
babyfacepro.c (vendor protocol/cold-init, PCM streaming, state
persistence, card lifecycle) and babyfacepro-ctl.c (the ALSA control
surface: mixer, front panel, EQ).
Validated on real hardware: full-duplex streaming across the whole
rate x period matrix with a signal-integrity tap, start/stop stress
(30 cycles), mixer-state restore across an interface unbind/rebind,
and a mid-stream disconnect, all via the automated regression suite
kept with the driver's development tree. sparse (C=1/C=2), W=1, and
checkpatch --strict are all clean; the driver also builds in-tree
against linux-next with W=1.
Known limitations, stated up front:
- USB autosuspend is not supported yet and is explicitly disabled
(usb_disable_autosuspend at probe, balanced at disconnect) rather
than shipped untested: the front-panel poll and keepalive work
items run continuously and nothing pairs usb_autopm_get/put around
the stream. S3 suspend/resume works and is tested; full autosuspend
(pausing the panel/keepalive work + autopm pairing) is a follow-up.
- A few protocol items are not fully pinned down but do not affect
the shipped controls (the relevant paths are hardware-verified);
documented as open in PROTOCOL.md: the preamp readback index
semantics (0x003F vs 0x0000), a width strip-ownership edge case,
and the exact high-frequency warping of the EQ coefficient
computation vs TotalMix's curve.
- The latency profile is selected at load time via the frames_per_urb
/ nurbs module params (default 256 frames/URB, matching TotalMix's
256-sample buffer; frames_per_urb=16 nurbs=16 gives a 0.33 ms
monitoring-grade floor). Changing profile currently means a module
reload; a runtime reconfiguration (RME's Fireface USB Settings-style
switch) is a post-merge follow-up.
Signed-off-by: Ismaïl Bahloul <i.bahloul01@gmail.com>
---
MAINTAINERS | 6 +
sound/usb/Kconfig | 18 +
sound/usb/Makefile | 2 +-
sound/usb/babyfacepro/Makefile | 2 +
sound/usb/babyfacepro/babyfacepro-ctl.c | 2782 +++++++++++++++++++++++
sound/usb/babyfacepro/babyfacepro.c | 1449 ++++++++++++
sound/usb/babyfacepro/babyfacepro.h | 391 ++++
7 files changed, 4649 insertions(+), 1 deletion(-)
create mode 100644 sound/usb/babyfacepro/Makefile
create mode 100644 sound/usb/babyfacepro/babyfacepro-ctl.c
create mode 100644 sound/usb/babyfacepro/babyfacepro.c
create mode 100644 sound/usb/babyfacepro/babyfacepro.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 7291238bc..3a1357492 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -23653,6 +23653,12 @@ F: include/dt-bindings/power/thead,th1520-power.h
F: include/dt-bindings/reset/thead,th1520-reset.h
F: include/linux/firmware/thead/thead,th1520-aon.h
+RME BABYFACE PRO FS DRIVER (PROPRIETARY MODE)
+M: Ismaïl Bahloul <i.bahloul01@gmail.com>
+L: alsa-devel@alsa-project.org (moderated for non-subscribers)
+S: Maintained
+F: sound/usb/babyfacepro/
+
RNBD BLOCK DRIVERS
M: Md. Haris Iqbal <haris.iqbal@ionos.com>
M: Jack Wang <jinpu.wang@ionos.com>
diff --git a/sound/usb/Kconfig b/sound/usb/Kconfig
index b4588915e..14d759814 100644
--- a/sound/usb/Kconfig
+++ b/sound/usb/Kconfig
@@ -204,6 +204,24 @@ config SND_USB_AUDIO_QMI
To compile this driver as a module, choose M here: the module
will be called snd-usb-audio-qmi.
+config SND_USB_BABYFACE_PRO
+ tristate "RME Babyface Pro FS (proprietary mode)"
+ select SND_PCM
+ help
+ Say Y here to include support for the RME Babyface Pro FS in
+ its proprietary mode (VID 0x2a39, PID 0x3fc0).
+
+ The proprietary mode streams PCM over interrupt endpoints
+ (interface 5, ep 0x01/0x82) instead of the class-compliant
+ isochronous path handled by snd-usb-audio, so this driver is
+ standalone (snd-usb-caiaq-style interrupt streaming). It
+ exposes the PCM stream plus the output masters, mutes, mic
+ phantom/PAD and preamp gains as standard ALSA controls.
+
+ To compile this driver as a module, choose M here: the module
+ will be called snd-usb-babyface-pro.
+
+
source "sound/usb/line6/Kconfig"
endif # SND_USB
diff --git a/sound/usb/Makefile b/sound/usb/Makefile
index e62794a87..2f83f5881 100644
--- a/sound/usb/Makefile
+++ b/sound/usb/Makefile
@@ -35,5 +35,5 @@ obj-$(CONFIG_SND_USB_UA101) += snd-usbmidi-lib.o
obj-$(CONFIG_SND_USB_USX2Y) += snd-usbmidi-lib.o
obj-$(CONFIG_SND_USB_US122L) += snd-usbmidi-lib.o
-obj-$(CONFIG_SND) += misc/ usx2y/ caiaq/ 6fire/ hiface/ bcd2000/ qcom/
+obj-$(CONFIG_SND) += misc/ usx2y/ caiaq/ 6fire/ hiface/ bcd2000/ qcom/ babyfacepro/
obj-$(CONFIG_SND_USB_LINE6) += line6/
diff --git a/sound/usb/babyfacepro/Makefile b/sound/usb/babyfacepro/Makefile
new file mode 100644
index 000000000..40badfd14
--- /dev/null
+++ b/sound/usb/babyfacepro/Makefile
@@ -0,0 +1,2 @@
+snd-usb-babyface-pro-y := babyfacepro.o babyfacepro-ctl.o
+obj-$(CONFIG_SND_USB_BABYFACE_PRO) += snd-usb-babyface-pro.o
diff --git a/sound/usb/babyfacepro/babyfacepro-ctl.c b/sound/usb/babyfacepro/babyfacepro-ctl.c
new file mode 100644
index 000000000..dfdff9485
--- /dev/null
+++ b/sound/usb/babyfacepro/babyfacepro-ctl.c
@@ -0,0 +1,2782 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * RME Babyface Pro FS — proprietary-mode USB audio driver
+ *
+ * ALSA control surface: mixer (masters, preamp, crosspoints, flags,
+ * gains), front-panel poll + controls, and the hardware DSP EQ
+ * (3-band + low cut).
+ *
+ * See babyfacepro.h for the shared device state and register map,
+ * and babyfacepro.c for the core driver (protocol, PCM streaming,
+ * state persistence, card lifecycle).
+ */
+#include <linux/log2.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/unaligned.h>
+#include <linux/usb.h>
+#include <linux/workqueue.h>
+#include <sound/control.h>
+#include <sound/tlv.h>
+#include <sound/core.h>
+#include <sound/initval.h>
+#include <sound/pcm.h>
+
+#include "babyfacepro.h"
+
+const struct bf_source bf_sources[14] = {
+ { "AN1", 0, 0 },
+ { "AN2", 1, 1 },
+ { "AN3", 2, 2 },
+ { "AN4", 3, 3 },
+ { "AS1/2", 4, 5 },
+ { "ADAT3/4", 6, 7 },
+ { "ADAT5/6", 8, 9 },
+ { "ADAT7/8", 10, 11 },
+ { "PB1", 12, 13 },
+ { "PB2", 14, 15 },
+ { "PB3", 16, 17 },
+ { "PB4", 18, 19 },
+ { "PB5", 20, 21 },
+ { "PB6", 22, 23 },
+};
+
+/* Crosspoint-map output order vs the master-map order — HARDWARE-
+ * VERIFIED 2026-08-24: the block that feeds the Phones is the FIRST
+ * crosspoint block (0x34), while the Phones master is the SECOND
+ * (0x03E2/0x0006). The crosspoint map lists the Phones first (the
+ * monitor output); the master map lists AN1/2 first. Control index =
+ * the canonical order (AN1/2=0, PH3/4=1, ...) so the crosspoint and
+ * master controls line up; this table maps to the register block.
+ */
+const u8 bf_xpoint_block[6] = { 1, 0, 2, 3, 4, 5 };
+
+/* Master-register output order — the master map lists AN1/2 first
+ * (0x03E0) and the Phones master SECOND (0x03E2, HARDWARE-VERIFIED
+ * 2026-08-24); the crosspoint blocks are in the opposite order
+ * (Phones = block 0x34 first, hence bf_xpoint_block above). Control
+ * index → canonical output (AN1/2=0, PH3/4=1, ...) = the master
+ * register position directly: the names 'AN1/2 Playback Volume' etc.
+ * must match the register they write (corrected 2026-08-26 — the
+ * previous {1,0,...} swap made 'AN1/2' drive the Phones and 'PH3/4'
+ * drive the AN1/2 analog out).
+ */
+static const u8 bf_master_out[6] = { 0, 1, 2, 3, 4, 5 };
+
+/* The 16-bit master value → the 8-bit companion code (0.5 dB/step).
+ * Integer-only: half_db = 12·log2(v/0x2000) via ilog2 + an 8-bit
+ * fractional-octave table (12·log2(1 + n/256), ~0.05 dB resolution —
+ * fine enough for the ±0.5 dB panel wheel to track the round-trip).
+ */
+static const u8 bf_lg2_frac[256] = {
+ 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5,
+ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10,
+ 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+ 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
+ 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
+ 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
+};
+
+/* 16-bit master → dB×2 (12 half-dB per octave; 0x2000 = 0 dB).
+ * Shared by the 8-bit companion and the front-panel OUT wheel.
+ */
+int bf_master_half_db(u16 vol16)
+{
+ unsigned int k, frac;
+
+ vol16 = clamp(vol16, 1, 0x4000);
+ k = ilog2(vol16);
+ frac = ((vol16 - (1u << k)) << 8) >> k;
+ return 12 * (int)k - 156 + bf_lg2_frac[frac];
+}
+
+/* dB×2 → 16-bit master (0x2000·2^(half_db/12), rounded). The
+ * inverse of bf_master_half_db — the 12th-root table 2^(n/12).
+ */
+static const u16 bf_twelfth[12] = {
+ 0x1000, 0x10f4, 0x11f6, 0x1307, 0x1429, 0x155c,
+ 0x16a1, 0x17f9, 0x1966, 0x1ae9, 0x1c82, 0x1e34,
+};
+
+int bf_master_16bit(int half_db)
+{
+ int k = half_db / 12;
+ int n = half_db % 12;
+ u32 v;
+
+ if (n < 0) {
+ n += 12;
+ k--;
+ }
+ v = (u32)bf_twelfth[n] << 1; /* 0x2000·2^(n/12) */
+ if (k >= 0) {
+ v <<= k;
+ } else {
+ v += 1u << (-k - 1); /* round-half-up */
+ v >>= -k;
+ }
+ return (u16)clamp(v, 1, 0x4000);
+}
+
+u8 bf_master_8bit(u16 vol16)
+{
+ if (vol16 == 0)
+ return BF_MASTER_MUTE;
+ return (u8)clamp(0xf3 + bf_master_half_db(vol16), BF_MASTER_8_MIN, 0xff);
+}
+
+/* The cold-init register clear zeroes the mixer registers TotalMix
+ * re-uploads afterwards. The kernel driver has no saved scene (no
+ * readback for faders), so it applies TotalMix's factory default:
+ * every source routed to every output at unity, masters at 0 dB and
+ * unmuted — the user/TuxMix can restore its own scene on top.
+ */
+int babyface_write_default_mixer(struct snd_usb_babyface *chip)
+{
+ int out, src, ret;
+ u16 flag;
+
+ /* Output masters: 0 dB (0x2000) + the unmute companion (0xf3). */
+ for (out = 0; out < 6; out++) {
+ ret = bf_vendor_write(chip, BF_REQ_GAIN, BF_MASTER_UNMUTE,
+ BF_REG_MASTER_8 + 2 * out);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_GAIN, BF_MASTER_UNMUTE,
+ BF_REG_MASTER_8 + 2 * out + 1);
+ if (ret < 0)
+ return ret;
+ flag = bf_flag_cycle[chip->flag_cnt];
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, BF_MASTER_0DB,
+ (BF_REG_MASTER_16 + 2 * out) | flag);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, BF_MASTER_0DB,
+ (BF_REG_MASTER_16 + 2 * out + 1) | flag);
+ if (ret < 0)
+ return ret;
+ chip->master[out][0] = BF_MASTER_0DB;
+ chip->master[out][1] = BF_MASTER_0DB;
+ chip->muted[out] = false;
+ }
+
+ /* Every source into every output pair, L and R, at 0 dB (the
+ * standard map; the low map is only a shadow). The addresses use
+ * the source's idx_l/idx_r on the canonical block — writing the raw
+ * index on both bases would put PB1 R on the L side and PB1 L on
+ * the R side (L+R on both = mono). The "cross" registers
+ * (L-reg idx_r / R-reg idx_l) are left at 0; the restore at stream
+ * start re-writes the same addresses from the cache.
+ */
+ for (out = 0; out < 6; out++) {
+ unsigned int blk = bf_xpoint_block[out];
+
+ for (src = 0; src < 14; src++) {
+ flag = bf_flag_cycle[chip->flag_cnt];
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, BF_FADER_0DB,
+ (BF_REG_CROSS_BASE_L +
+ BF_REG_CROSS_STRIDE * blk +
+ bf_sources[src].idx_l) | flag);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, BF_FADER_0DB,
+ (BF_REG_CROSS_BASE_R +
+ BF_REG_CROSS_STRIDE * blk +
+ bf_sources[src].idx_r) | flag);
+ if (ret < 0)
+ return ret;
+ }
+ ret = bf_crosspoint_clear_cross(chip, blk);
+ if (ret < 0)
+ return ret;
+ }
+
+ /* Mirror the defaults into the control cache (14 controls/output). */
+ for (out = 0; out < 6; out++)
+ for (src = 0; src < 14; src++) {
+ chip->xpoint[out][src][0] = BF_FADER_0DB;
+ chip->xpoint[out][src][1] = BF_FADER_0DB;
+ }
+
+ /* Host settings word: clock Internal (0x0001). */
+ return bf_vendor_write(chip, BF_REQ_KEEPALIVE, 0x0001,
+ BF_REG_KEEPALIVE_SETTINGS);
+}
+
+/* The device resets its output masters to mute when a stream session
+ * starts (hardware-verified 2026-08-24: after a stream start the
+ * output stays silent until a master write lands — only a write
+ * un-mutes the 8-bit register). Re-apply the six output masters +
+ * mutes from the cache; also used by the PM restore path.
+ */
+int bf_apply_masters(struct snd_usb_babyface *chip)
+{
+ int out, ret;
+ u16 flag;
+
+ for (out = 0; out < 6; out++) {
+ u16 l = chip->muted[out] ? 0 : chip->master[out][0];
+ u16 r = chip->muted[out] ? 0 : chip->master[out][1];
+ u8 l8 = chip->muted[out] ? BF_MASTER_MUTE : bf_master_8bit(l);
+ u8 r8 = chip->muted[out] ? BF_MASTER_MUTE : bf_master_8bit(r);
+
+ ret = bf_vendor_write(chip, BF_REQ_GAIN, l8,
+ BF_REG_MASTER_8 + 2 * out);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_GAIN, r8,
+ BF_REG_MASTER_8 + 2 * out + 1);
+ if (ret < 0)
+ return ret;
+ flag = bf_flag_cycle[chip->flag_cnt];
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, l,
+ (BF_REG_MASTER_16 + 2 * out) | flag);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, r,
+ (BF_REG_MASTER_16 + 2 * out + 1) | flag);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
+/* ── mixer controls ──────────────────────── */
+
+/* dB TLV for the output masters: 0x2000 = 0 dB, 0x4000 = +6 dB
+ * (CALIBRATION.md) with the hardware 20*log10(v/0x2000) law — the raw
+ * 16-bit value IS the linear amplitude. WirePlumber needs this to map
+ * the volume 1:1 to the hardware control instead of applying a software
+ * volume on top (which left the output ~30 dB down).
+ */
+static const DECLARE_TLV_DB_RANGE(bf_master_tlv,
+ 0, 0x2000, TLV_DB_LINEAR_ITEM(-6500, 0),
+ 0x2000, 0x4000, TLV_DB_LINEAR_ITEM(0, 600)
+);
+
+static int bf_master_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+ uinfo->count = 2;
+ uinfo->value.integer.min = 0;
+ uinfo->value.integer.max = 0x4000; /* +6 dB = 2 × 0dB(0x2000) */
+ uinfo->value.integer.step = 1;
+ return 0;
+}
+
+static int bf_master_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ int out = bf_master_out[kctl->private_value];
+
+ ucontrol->value.integer.value[0] = chip->master[out][0];
+ ucontrol->value.integer.value[1] = chip->master[out][1];
+ return 0;
+}
+
+static int bf_master_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ int out = bf_master_out[kctl->private_value];
+ u16 l = ucontrol->value.integer.value[0];
+ u16 r = ucontrol->value.integer.value[1];
+ u16 flag;
+ int ret = 0;
+
+ mutex_lock(&chip->mutex);
+ if (l == chip->master[out][0] && r == chip->master[out][1])
+ goto out;
+
+ flag = bf_flag_cycle[chip->flag_cnt];
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+
+ /* The 8-bit register is the real volume; the 16-bit is its
+ * companion (kept in sync like TotalMix).
+ */
+ ret = bf_vendor_write(chip, BF_REQ_GAIN, bf_master_8bit(l),
+ BF_REG_MASTER_8 + 2 * out);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_GAIN, bf_master_8bit(r),
+ BF_REG_MASTER_8 + 2 * out + 1);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, l,
+ (BF_REG_MASTER_16 + 2 * out) | flag);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, r,
+ (BF_REG_MASTER_16 + 2 * out + 1) | flag);
+ if (ret < 0)
+ goto out;
+
+ chip->master[out][0] = l;
+ chip->master[out][1] = r;
+ chip->muted[out] = false;
+ /* A Phones change while DIM is engaged re-bases the restore point. */
+ if (chip->dim && out == 1) {
+ chip->dim_saved[0] = l;
+ chip->dim_saved[1] = r;
+ }
+ ret = 1;
+out:
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+static int bf_mute_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
+ uinfo->count = 2;
+ uinfo->value.integer.min = 0;
+ uinfo->value.integer.max = 1;
+ return 0;
+}
+
+static int bf_mute_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ int out = bf_master_out[kctl->private_value];
+
+ /* ALSA convention: 1 = enabled (sound on) = not muted. */
+ ucontrol->value.integer.value[0] = !chip->muted[out];
+ ucontrol->value.integer.value[1] = !chip->muted[out];
+ return 0;
+}
+
+static int bf_mute_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ int out = bf_master_out[kctl->private_value];
+ bool muted = !ucontrol->value.integer.value[0];
+ u16 flag;
+ int ret = 0;
+
+ mutex_lock(&chip->mutex);
+ if (muted == chip->muted[out])
+ goto out;
+
+ flag = bf_flag_cycle[chip->flag_cnt];
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+
+ if (muted) {
+ ret = bf_vendor_write(chip, BF_REQ_GAIN, BF_MASTER_MUTE,
+ BF_REG_MASTER_8 + 2 * out);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_GAIN, BF_MASTER_MUTE,
+ BF_REG_MASTER_8 + 2 * out + 1);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0000,
+ (BF_REG_MASTER_16 + 2 * out) | flag);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0000,
+ (BF_REG_MASTER_16 + 2 * out + 1) | flag);
+ if (ret < 0)
+ goto out;
+ } else {
+ /* Unmute restores the cached volume (TotalMix keeps the
+ * pre-mute fader value host-side), 8-bit + 16-bit.
+ */
+ ret = bf_vendor_write(chip, BF_REQ_GAIN,
+ bf_master_8bit(chip->master[out][0]),
+ BF_REG_MASTER_8 + 2 * out);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_GAIN,
+ bf_master_8bit(chip->master[out][1]),
+ BF_REG_MASTER_8 + 2 * out + 1);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT,
+ chip->master[out][0],
+ (BF_REG_MASTER_16 + 2 * out) | flag);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT,
+ chip->master[out][1],
+ (BF_REG_MASTER_16 + 2 * out + 1) | flag);
+ if (ret < 0)
+ goto out;
+ }
+ chip->muted[out] = muted;
+ ret = 1;
+out:
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+int bf_preamp_state_write(struct snd_usb_babyface *chip)
+{
+ int ret;
+
+ ret = bf_vendor_write(chip, BF_REQ_PREAMP, chip->preamp, BF_REG_PREAMP);
+ if (ret < 0)
+ return ret;
+ return bf_vendor_write(chip, BF_REQ_PREAMP_COMMIT, 0x0000, 0x0000);
+}
+
+/* ── crosspoint matrix (6 outputs × 14 sources) ────────────── */
+
+static int bf_xpoint_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+ uinfo->count = 2;
+ uinfo->value.integer.min = 0;
+ uinfo->value.integer.max = BF_FADER_TOP; /* +6 dB fader top */
+ uinfo->value.integer.step = 1;
+ return 0;
+}
+
+static int bf_xpoint_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ int out = kctl->private_value >> 8;
+ int src = kctl->private_value & 0xff;
+
+ ucontrol->value.integer.value[0] = chip->xpoint[out][src][0];
+ ucontrol->value.integer.value[1] = chip->xpoint[out][src][1];
+ return 0;
+}
+
+static int bf_xpoint_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ int out = kctl->private_value >> 8;
+ int src = kctl->private_value & 0xff;
+ unsigned int blk = bf_xpoint_block[out];
+ const struct bf_source *s = &bf_sources[src];
+ u16 l = ucontrol->value.integer.value[0];
+ u16 r = ucontrol->value.integer.value[1];
+ u16 flag;
+ int ret = 0;
+
+ if (l > BF_FADER_TOP || r > BF_FADER_TOP)
+ return -EINVAL;
+
+ mutex_lock(&chip->mutex);
+ if (l == chip->xpoint[out][src][0] && r == chip->xpoint[out][src][1])
+ goto out;
+
+ flag = bf_flag_cycle[chip->flag_cnt];
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+
+ /* L register = 0x0034 + 0x34·blk + idx, R = 0x004E + 0x34·blk + idx
+ * (mono sources use the same idx on both sides).
+ */
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, l,
+ (BF_REG_CROSS_BASE_L + BF_REG_CROSS_STRIDE * blk +
+ s->idx_l) | flag);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, r,
+ (BF_REG_CROSS_BASE_R + BF_REG_CROSS_STRIDE * blk +
+ s->idx_r) | flag);
+ if (ret < 0)
+ goto out;
+
+ chip->xpoint[out][src][0] = l;
+ chip->xpoint[out][src][1] = r;
+ ret = 1;
+out:
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+int babyface_create_xpoints(struct snd_usb_babyface *chip)
+{
+ struct snd_kcontrol *kctl;
+ int out, src, err;
+
+ for (out = 0; out < 6; out++) {
+ for (src = 0; src < 14; src++) {
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Playback Volume",
+ .index = out * 14 + src,
+ .info = bf_xpoint_info,
+ .get = bf_xpoint_get,
+ .put = bf_xpoint_put,
+ .private_value = (out << 8) | src,
+ }, chip);
+ /* Name the control by its source: "AN1 Playback Volume",
+ * "PB1 Playback Volume"... with a unique index.
+ */
+ strscpy(kctl->id.name, bf_sources[src].name,
+ sizeof(kctl->id.name));
+ strlcat(kctl->id.name, " Playback Volume",
+ sizeof(kctl->id.name));
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+ }
+ }
+ return 0;
+}
+
+/* ── flags / special controls (pitch, loopback, link, width, FX) ── */
+
+static int bf_switch_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
+ uinfo->count = 1;
+ uinfo->value.integer.min = 0;
+ uinfo->value.integer.max = 1;
+ return 0;
+}
+
+static int bf_pitch_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+ uinfo->count = 1;
+ uinfo->value.integer.min = -50; /* -5.0 % */
+ uinfo->value.integer.max = 50; /* +5.0 % */
+ uinfo->value.integer.step = 1; /* 0.1 % */
+ return 0;
+}
+
+static int bf_pitch_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+
+ ucontrol->value.integer.value[0] = chip->pitch;
+ return 0;
+}
+
+static int bf_pitch_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ int p = ucontrol->value.integer.value[0];
+ u32 dds24, dds16;
+ u16 frac, b1, b2;
+ int ret = 0;
+
+ if (p < -50 || p > 50)
+ return -EINVAL;
+
+ mutex_lock(&chip->mutex);
+ if (p == chip->pitch)
+ goto out;
+
+ /* The 0x1B DDS quad (16.8 fixed point, banked). p is 0.1 % steps:
+ * DDS_24 = round(50000·256/(1+p/1000)) = round(12800000000/(1000+p)).
+ */
+ dds24 = (12800000000u + (u32)(1000 + p) / 2) / (u32)(1000 + p);
+ dds16 = dds24 >> 8;
+ frac = dds24 & 0xff;
+ b1 = (u16)((dds16 * 72562ull + 50000) / 100000);
+ b2 = (u16)((dds16 * 2 + 1) / 3);
+
+ ret = bf_vendor_write(chip, BF_REQ_DDS, (u16)dds16, (frac << 8) | 0);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_DDS, b1, 0x0001);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_DDS, b2, 0x0002);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_DDS, 0x7cff, 0x0003);
+ if (ret < 0)
+ goto out;
+ /* Every quad must be followed by the clock keepalive. */
+ ret = bf_vendor_write(chip, BF_REQ_KEEPALIVE, 0x0001,
+ BF_REG_KEEPALIVE_SETTINGS);
+ if (ret < 0)
+ goto out;
+
+ chip->pitch = p;
+ ret = 1;
+out:
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+static int bf_loopback_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ int out = kctl->private_value;
+
+ ucontrol->value.integer.value[0] = chip->loopback[out];
+ ucontrol->value.integer.value[1] = chip->loopback[out];
+ return 0;
+}
+
+/* Write the full 30-channel loopback map: pair (2·out, 2·out+1) at
+ * `on` (0x0001/0x0000), all other channels cleared — exactly what
+ * TotalMix sends on every loopback toggle (cap_loopback2.pcap). The
+ * full-map write is also the reliable OFF (the old per-pair write
+ * sometimes failed to disengage on the hardware).
+ */
+int bf_loopback_write_map(struct snd_usb_babyface *chip, int out,
+ bool on)
+{
+ int ch, ret;
+
+ for (ch = 0; ch < BF_LOOPBACK_CHANNELS; ch++) {
+ u16 val = (on && (ch == out * 2 || ch == out * 2 + 1))
+ ? 0x0001 : 0x0000;
+
+ ret = bf_vendor_write(chip, BF_REQ_LOOPBACK, val, ch);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
+static int bf_loopback_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ int out = kctl->private_value;
+ bool on = ucontrol->value.integer.value[0];
+ int ret = 0;
+
+ mutex_lock(&chip->mutex);
+ if (on == chip->loopback[out])
+ goto out;
+ ret = bf_loopback_write_map(chip, out, on);
+ if (ret < 0)
+ goto out;
+ /* Single-active model (TotalMix writes one pair at 0x0001, the
+ * rest 0x0000): toggling one output clears the others.
+ */
+ memset(chip->loopback, 0, sizeof(chip->loopback));
+ chip->loopback[out] = on;
+ ret = 1;
+out:
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+static int bf_an12_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+
+ ucontrol->value.integer.value[0] = chip->an12;
+ return 0;
+}
+
+static int bf_an12_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ bool an12 = ucontrol->value.integer.value[0];
+ u16 v;
+ int ret = 0;
+
+ mutex_lock(&chip->mutex);
+ if (an12 == chip->an12)
+ goto out;
+ v = (chip->linked ? 0x0400 : 0x0000) | (an12 ? 0x1000 : 0x0000);
+ ret = bf_vendor_write(chip, BF_REQ_PREAMP, v, 0x1000);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_PREAMP_COMMIT, 0x0000, 0x0000);
+ if (ret < 0)
+ goto out;
+ chip->an12 = an12;
+ ret = 1;
+out:
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+static int bf_link_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+
+ ucontrol->value.integer.value[0] = chip->linked;
+ return 0;
+}
+
+static int bf_link_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ bool linked = ucontrol->value.integer.value[0];
+ u16 v;
+ int ret = 0;
+
+ mutex_lock(&chip->mutex);
+ if (linked == chip->linked)
+ goto out;
+ v = (linked ? 0x0400 : 0x0000) | (chip->an12 ? 0x1000 : 0x0000);
+ ret = bf_vendor_write(chip, BF_REQ_PREAMP, v, 0x1000);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_PREAMP_COMMIT, 0x0000, 0x0000);
+ if (ret < 0)
+ goto out;
+ chip->linked = linked;
+ ret = 1;
+out:
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+static int bf_ms_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+
+ ucontrol->value.integer.value[0] = chip->ms_proc;
+ return 0;
+}
+
+/* MS-proc: engage per the cap_ms2.pcap ON pattern — write 0x0000 to
+ * ALL FOUR AN2 (side) crosspoints: standard map 0x0035/0x004F (L/R)
+ * + low map 0x0001/0x001B (L/R) — the side path is muted (ear-
+ * verified 2026-08-26 with the mic on AN2: MS ON = silence); release
+ * restores the cached fader values (host-side, like TotalMix).
+ * (The 0x1000/0x0004 writes are the DISENGAGE restore values seen in
+ * cap_ms2 — the driver had them inverted on the engage path.)
+ */
+static int bf_ms_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ bool on = ucontrol->value.integer.value[0];
+ int ret = 0;
+
+ mutex_lock(&chip->mutex);
+ if (on == chip->ms_proc)
+ goto out;
+ if (on) {
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0000, 0x0035);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0000, 0x004f);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0000, 0x0001);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0000, 0x001b);
+ if (ret < 0)
+ goto out;
+ } else {
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT,
+ chip->xpoint[1][1][0], 0x0001);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT,
+ chip->xpoint[1][1][0], 0x0035);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT,
+ chip->xpoint[1][1][1], 0x001b);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT,
+ chip->xpoint[1][1][1], 0x004f);
+ if (ret < 0)
+ goto out;
+ }
+ chip->ms_proc = on;
+ ret = 1;
+out:
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+/* DIM — cap_dim2.pcap: an absolute -20 dB on the Phones master
+ * (out 1: 8-bit 0xCB / 16-bit 0x0333) regardless of the current level,
+ * plus the 0x17 wVal=0x2000 wIdx=0x2000 flag; release restores the
+ * pre-DIM master host-side. The master cache keeps the real volume.
+ */
+static int bf_dim_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+
+ ucontrol->value.integer.value[0] = chip->dim;
+ return 0;
+}
+
+static int bf_dim_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ bool on = ucontrol->value.integer.value[0];
+ u16 flag;
+ int ret = 0;
+
+ mutex_lock(&chip->mutex);
+ if (on == chip->dim)
+ goto out;
+ if (on) {
+ chip->dim_saved[0] = chip->master[1][0];
+ chip->dim_saved[1] = chip->master[1][1];
+ ret = bf_vendor_write(chip, BF_REQ_GAIN, 0xcb,
+ BF_REG_MASTER_8 + 2 * 1);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_GAIN, 0xcb,
+ BF_REG_MASTER_8 + 2 * 1 + 1);
+ if (ret < 0)
+ goto out;
+ flag = bf_flag_cycle[chip->flag_cnt];
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0333,
+ (BF_REG_MASTER_16 + 2 * 1) | flag);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0333,
+ (BF_REG_MASTER_16 + 2 * 1 + 1) | flag);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_PREAMP, 0x2000, 0x2000);
+ if (ret < 0)
+ goto out;
+ } else {
+ ret = bf_vendor_write(chip, BF_REQ_GAIN,
+ bf_master_8bit(chip->dim_saved[0]),
+ BF_REG_MASTER_8 + 2 * 1);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_GAIN,
+ bf_master_8bit(chip->dim_saved[1]),
+ BF_REG_MASTER_8 + 2 * 1 + 1);
+ if (ret < 0)
+ goto out;
+ flag = bf_flag_cycle[chip->flag_cnt];
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT,
+ chip->dim_saved[0],
+ (BF_REG_MASTER_16 + 2 * 1) | flag);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT,
+ chip->dim_saved[1],
+ (BF_REG_MASTER_16 + 2 * 1 + 1) | flag);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_PREAMP, 0x0000, 0x2000);
+ if (ret < 0)
+ goto out;
+ }
+ chip->dim = on;
+ ret = 1;
+out:
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+static int bf_width_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+ uinfo->count = 1;
+ uinfo->value.integer.min = -100;
+ uinfo->value.integer.max = 100;
+ uinfo->value.integer.step = 1;
+ return 0;
+}
+
+static int bf_width_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+
+ ucontrol->value.integer.value[0] = chip->width;
+ return 0;
+}
+
+static int bf_width_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ int w = ucontrol->value.integer.value[0];
+ u16 l, r;
+ int ret = 0;
+
+ if (w < -100 || w > 100)
+ return -EINVAL;
+
+ mutex_lock(&chip->mutex);
+ if (w == chip->width)
+ goto out;
+ /* Width spread: L = 0x1000·(1+w), R = 0x1000·(1−w), L+R = 0x2000.
+ * TotalMix writes the strip's src pair on BOTH maps (cap_width3-7,
+ * PROTOCOL.md “Width strip mapping”): the low map (0x0000+src L /
+ * 0x001A+src R) and the std block-0 map (0x0034+src L /
+ * 0x004E+src R) — the stereo pair spreads L/R in opposition, the
+ * mirror src (AN2) gets the swapped values.
+ */
+ l = (u16)(((0x2000 * (100 + w) / 2) + 50) / 100);
+ r = 0x2000 - l;
+ /* Low map: AN1 L=0x0000, R=0x001A; AN2 L=0x0001, R=0x001B. */
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, l, 0x0000);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, r, 0x001a);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, r, 0x0001);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, l, 0x001b);
+ if (ret < 0)
+ goto out;
+ /* Std block-0 map (item 0b, the missing half): AN1 L=0x0034,
+ * R=0x004E; AN2 L=0x0035, R=0x004F. (The playback strips PB2-6
+ * target block n−2 — 0x00AE family — reserved for the per-strip
+ * controls.)
+ */
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, l, 0x0034);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, r, 0x004e);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, r, 0x0035);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, l, 0x004f);
+ if (ret < 0)
+ goto out;
+ chip->width = w;
+ ret = 1;
+out:
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+static int bf_fx_send_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+ uinfo->count = 1;
+ uinfo->value.integer.min = 0;
+ uinfo->value.integer.max = 0x1000;
+ uinfo->value.integer.step = 1;
+ return 0;
+}
+
+static int bf_fx_send_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+
+ ucontrol->value.integer.value[0] = chip->fx_send;
+ return 0;
+}
+
+static int bf_fx_send_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ u16 v = ucontrol->value.integer.value[0];
+ int ret = 0;
+
+ if (v > 0x1000)
+ return -EINVAL;
+
+ mutex_lock(&chip->mutex);
+ if (v == chip->fx_send)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, v, 0x0138);
+ if (ret < 0)
+ goto out;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, v, 0x0153);
+ if (ret < 0)
+ goto out;
+ chip->fx_send = v;
+ ret = 1;
+out:
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+int babyface_create_flags(struct snd_usb_babyface *chip)
+{
+ struct snd_kcontrol *kctl;
+ int i, err;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Varispeed Pitch",
+ .info = bf_pitch_info,
+ .get = bf_pitch_get,
+ .put = bf_pitch_put,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+
+ for (i = 0; i < 6; i++) {
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Loopback Switch",
+ .index = i,
+ .info = bf_mute_info,
+ .get = bf_loopback_get,
+ .put = bf_loopback_put,
+ .private_value = i,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+ }
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "AN 1>2 Switch",
+ .info = bf_switch_info,
+ .get = bf_an12_get,
+ .put = bf_an12_put,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "AN1/2 Link Switch",
+ .info = bf_switch_info,
+ .get = bf_link_get,
+ .put = bf_link_put,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "MS Processor Switch",
+ .info = bf_switch_info,
+ .get = bf_ms_get,
+ .put = bf_ms_put,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Dim Switch",
+ .info = bf_switch_info,
+ .get = bf_dim_get,
+ .put = bf_dim_put,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Width",
+ .info = bf_width_info,
+ .get = bf_width_get,
+ .put = bf_width_put,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "FX Send Volume",
+ .info = bf_fx_send_info,
+ .get = bf_fx_send_get,
+ .put = bf_fx_send_put,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+
+ return 0;
+}
+
+static int bf_bool_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
+ uinfo->count = 1;
+ uinfo->value.integer.min = 0;
+ uinfo->value.integer.max = 1;
+ return 0;
+}
+
+static int bf_phantom_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+
+ ucontrol->value.integer.value[0] =
+ !!(chip->preamp & kctl->private_value);
+ return 0;
+}
+
+static int bf_phantom_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ u16 bit = kctl->private_value;
+ bool on = ucontrol->value.integer.value[0];
+ bool cur = !!(chip->preamp & bit);
+ int ret = 0;
+
+ mutex_lock(&chip->mutex);
+ if (on == cur)
+ goto out;
+ chip->preamp = on ? (chip->preamp | bit) : (chip->preamp & ~bit);
+ ret = bf_preamp_state_write(chip);
+ if (ret < 0)
+ goto out;
+ ret = 1;
+out:
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+/* Gain scales: the mic preamps (AN1/2) span 0-65 dB over raw 0-20
+ * (3.25 dB/step); the Hi-Z instrument inputs (AN3/4) are digitally
+ * limited to 9 dB over raw 0-18 (0.5 dB/step) — manual §10, raw
+ * ranges verified from cap_gain12/cap_gain34.pcap. Shared by the GUI
+ * controls and the front-panel gain wheel.
+ */
+int bf_gain_max_db(int mic)
+{
+ return mic < 2 ? BF_GAIN_MAX_DB : 9;
+}
+
+int bf_gain_db(int mic, u8 raw)
+{
+ return mic < 2 ? (raw * 13) / 4 : raw / 2;
+}
+
+u8 bf_gain_raw(int mic, int db)
+{
+ return mic < 2 ? (db * 8 + 13) / 26 : db * 2;
+}
+
+static int bf_gain_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+ uinfo->count = 1;
+ uinfo->value.integer.min = 0;
+ uinfo->value.integer.max = bf_gain_max_db(kctl->private_value);
+ uinfo->value.integer.step = 1;
+ return 0;
+}
+
+static int bf_gain_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ int mic = kctl->private_value;
+
+ /* chip->gain[] tracks the dB (the raw is derived at write time —
+ * the 3.25 dB/step mic grid would otherwise make a ±1 dB wheel
+ * stick on a raw boundary).
+ */
+ ucontrol->value.integer.value[0] = chip->gain[mic];
+ return 0;
+}
+
+static int bf_gain_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ int mic = kctl->private_value;
+ int db = ucontrol->value.integer.value[0];
+ u8 raw, counter;
+ int ret = 0;
+
+ if (db < 0 || db > bf_gain_max_db(mic))
+ return -EINVAL;
+
+ mutex_lock(&chip->mutex);
+ if (db == chip->gain[mic])
+ goto out;
+ raw = bf_gain_raw(mic, db);
+ counter = (chip->gain_cycle % 3 == 0) ? 0x20 :
+ (chip->gain_cycle % 3 == 1) ? 0x00 : 0x40;
+ chip->gain_cycle = (chip->gain_cycle + 1) % 3;
+
+ ret = bf_vendor_write(chip, BF_REQ_GAIN,
+ (u16)((raw & 0x1f) | counter),
+ BF_REG_GAIN + mic);
+ if (ret < 0)
+ goto out;
+ chip->gain[mic] = db;
+ ret = 1;
+out:
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+int babyface_create_controls(struct snd_usb_babyface *chip)
+{
+ static const char * const out_names[6] = {
+ "AN1/2", "PH3/4", "AS1/2", "ADAT3/4", "ADAT5/6", "ADAT7/8"
+ };
+ struct snd_kcontrol *kctl;
+ int i, err;
+
+ for (i = 0; i < 6; i++) {
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = out_names[i],
+ .index = i,
+ .access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
+ SNDRV_CTL_ELEM_ACCESS_TLV_READ,
+ .info = bf_master_info,
+ .get = bf_master_get,
+ .put = bf_master_put,
+ .tlv.p = bf_master_tlv,
+ .private_value = i,
+ }, chip);
+ strlcat(kctl->id.name, " Playback Volume", sizeof(kctl->id.name));
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = out_names[i],
+ .index = i,
+ .info = bf_mute_info,
+ .get = bf_mute_get,
+ .put = bf_mute_put,
+ .private_value = i,
+ }, chip);
+ strlcat(kctl->id.name, " Playback Switch", sizeof(kctl->id.name));
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+
+ dev_dbg(&chip->dev->dev, "output %d = %s\n", i, out_names[i]);
+ }
+
+ for (i = 0; i < 2; i++) {
+ u16 bit = i == 0 ? BF_PREAMP_48V_MIC1 : BF_PREAMP_48V_MIC2;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Phantom Power Mic 1",
+ .index = i,
+ .info = bf_bool_info,
+ .get = bf_phantom_get,
+ .put = bf_phantom_put,
+ .private_value = bit,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+ }
+
+ for (i = 0; i < 2; i++) {
+ u16 bit = i == 0 ? BF_PREAMP_PAD_MIC1 : BF_PREAMP_PAD_MIC2;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Pad Mic 1",
+ .index = i,
+ .info = bf_bool_info,
+ .get = bf_phantom_get,
+ .put = bf_phantom_put,
+ .private_value = bit,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+ }
+
+ for (i = 0; i < 4; i++) {
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Mic 1 Capture Volume",
+ .index = i,
+ .info = bf_gain_info,
+ .get = bf_gain_get,
+ .put = bf_gain_put,
+ .private_value = i,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+ }
+ return 0;
+}
+
+/* Control indices in chip->panel_kctl[] (for snd_ctl_notify). */
+enum {
+ BF_PANEL_KCTL_BUTTON,
+ BF_PANEL_KCTL_WHEEL,
+ BF_PANEL_KCTL_IN,
+ BF_PANEL_KCTL_OUT,
+ BF_PANEL_KCTL_MIX,
+ BF_PANEL_KCTL_DIM,
+ BF_PANEL_KCTL_SELECT,
+ BF_PANEL_KCTL_NUM,
+};
+
+static const char *const bf_panel_in_texts[] = {
+ "Unknown", "Ch 1/2", "Ch 3/4", "Opt", NULL
+};
+
+static const char *const bf_panel_out_texts[] = {
+ "Unknown", "Ch 1/2", "Phones", "Opt", NULL
+};
+
+static const char *const bf_panel_select_texts[] = {
+ "Left", "Right", "Both", "None", NULL
+};
+
+/* byte3 button flash → event code (0 = none). The idle byte3 is 0x40;
+ * a press flashes the value below the base for one or two poll frames.
+ */
+static int bf_panel_button_decode(u8 flash)
+{
+ switch (flash) {
+ case BF_PANEL_FLASH_IN: return BF_PANEL_BTN_IN;
+ case BF_PANEL_FLASH_SET: return BF_PANEL_BTN_SET;
+ case BF_PANEL_FLASH_MIX: return BF_PANEL_BTN_MIX;
+ case BF_PANEL_FLASH_OUT: return BF_PANEL_BTN_OUT;
+ case BF_PANEL_FLASH_SELECT: return BF_PANEL_BTN_SELECT;
+ case BF_PANEL_FLASH_DIM: return BF_PANEL_BTN_DIM;
+ default: return BF_PANEL_BTN_NONE;
+ }
+}
+
+/* (byte2 >> 4) & 7 = IN position 4/5/6 → enum index (0 = not in range). */
+static int bf_panel_in_decode(u8 nib)
+{
+ switch (nib) {
+ case BF_PANEL_IN_CH12: return 1;
+ case BF_PANEL_IN_CH34: return 2;
+ case BF_PANEL_IN_OPT: return 3;
+ default: return 0;
+ }
+}
+
+/* byte1 & 7 = OUT position. Two encodings seen in captures: the
+ * gain-display mode 0x04/0x05/0x06 (cap_dim.pcap, cap_buttons2.pcap)
+ * and the base mode 0x01/0x02/0x00 (cap_buttons.pcap; 0x01 is also the
+ * idle byte1 of cap_padpan.pcap and the live device). Accept both;
+ * 0x00 is ambiguous (could be Opt or no selection) so keep previous.
+ */
+static int bf_panel_out_decode(u8 v)
+{
+ switch (v) {
+ case BF_PANEL_OUT_CH12: return 1;
+ case BF_PANEL_OUT_PHONES: return 2;
+ case BF_PANEL_OUT_OPT: return 3;
+ case 0x01: return 1; /* base-mode Ch 1/2 */
+ case 0x02: return 2; /* base-mode Phones */
+ default: return 0;
+ }
+}
+
+/* ── MIX-mode monitoring level (fader curve) ────────────────
+ * Calibrated crosspoint-fader curve (AN1→AN1/2, cap_calib.pcap
+ * 2026-08-22; the same table as tuxmix-core/src/usb.rs FADER_CURVE).
+ * dB stored ×2 (half-dB grid): the MIX wheel steps ±0.5 dB per click
+ * on this curve (cap_mix.pcap). 0x0000 = −inf (digital mute),
+ * 0x0003 = −62 dB, … 0x2D41 = +6 dB. Raw values interpolate linearly
+ * between the 1-dB points.
+ */
+#define BF_FADER_DB2_INF (-130) /* −65 dB = the wheel's −inf floor */
+
+static const struct bf_fader_pt {
+ s16 db2; /* dB × 2 */
+ u16 raw;
+} bf_fader_curve[] = {
+ { -124, 0x0003 }, { -122, 0x0004 }, { -120, 0x0005 },
+ { -118, 0x0006 }, { -116, 0x0007 }, { -114, 0x0008 },
+ { -112, 0x0009 }, { -110, 0x000a }, { -108, 0x000b },
+ { -106, 0x000d }, { -104, 0x000e }, { -102, 0x0010 },
+ { -100, 0x0012 }, { -98, 0x0014 }, { -96, 0x0017 },
+ { -94, 0x0019 }, { -92, 0x001d }, { -90, 0x0020 },
+ { -88, 0x0024 }, { -86, 0x0029 }, { -84, 0x002e },
+ { -82, 0x0033 }, { -80, 0x003a }, { -78, 0x0041 },
+ { -76, 0x0049 }, { -74, 0x0051 }, { -72, 0x005b },
+ { -70, 0x0067 }, { -68, 0x0073 }, { -66, 0x0081 },
+ { -64, 0x0091 }, { -62, 0x00a3 }, { -60, 0x00b7 },
+ { -58, 0x00cd }, { -56, 0x00e6 }, { -54, 0x0102 },
+ { -52, 0x0122 }, { -50, 0x0145 }, { -48, 0x016d },
+ { -46, 0x019a }, { -44, 0x01cc }, { -42, 0x0204 },
+ { -40, 0x0243 }, { -38, 0x028a }, { -36, 0x02d9 },
+ { -34, 0x0332 }, { -32, 0x0396 }, { -30, 0x0406 },
+ { -28, 0x0483 }, { -26, 0x0510 }, { -24, 0x05af },
+ { -22, 0x0660 }, { -20, 0x0727 }, { -18, 0x0807 },
+ { -16, 0x0902 }, { -14, 0x0a1b }, { -12, 0x0b57 },
+ { -10, 0x0cb9 }, { -8, 0x0e47 }, { -6, 0x1004 },
+ { -4, 0x11f9 }, { -2, 0x142a }, { 0, 0x16a0 },
+ { 2, 0x1963 }, { 4, 0x1c7c }, { 6, 0x1ff6 },
+ { 8, 0x23dc }, { 10, 0x283d }, { 12, 0x2d41 },
+};
+
+/* Fader raw → dB×2 (linear interpolation; raw 0 = −inf). */
+static int bf_fader_raw_to_db2(u16 raw)
+{
+ int i;
+
+ if (raw == 0 || raw < bf_fader_curve[0].raw)
+ return BF_FADER_DB2_INF;
+ for (i = 0; i < ARRAY_SIZE(bf_fader_curve) - 1; i++) {
+ if (raw <= bf_fader_curve[i + 1].raw) {
+ u32 num = (u32)(raw - bf_fader_curve[i].raw) *
+ (u32)(bf_fader_curve[i + 1].db2 - bf_fader_curve[i].db2);
+ u32 den = bf_fader_curve[i + 1].raw - bf_fader_curve[i].raw;
+
+ return bf_fader_curve[i].db2 + (int)((num + den / 2) / den);
+ }
+ }
+ return bf_fader_curve[ARRAY_SIZE(bf_fader_curve) - 1].db2;
+}
+
+/* dB×2 → fader raw (linear interpolation; below −62 dB = mute 0). */
+static u16 bf_fader_db2_to_raw(int db2)
+{
+ int i;
+
+ if (db2 <= bf_fader_curve[0].db2)
+ return db2 < bf_fader_curve[0].db2 ? 0 : bf_fader_curve[0].raw;
+ for (i = 0; i < ARRAY_SIZE(bf_fader_curve) - 1; i++) {
+ if (db2 <= bf_fader_curve[i + 1].db2) {
+ u32 num = (u32)(db2 - bf_fader_curve[i].db2) *
+ (u32)(bf_fader_curve[i + 1].raw - bf_fader_curve[i].raw);
+ u32 den = bf_fader_curve[i + 1].db2 - bf_fader_curve[i].db2;
+
+ return bf_fader_curve[i].raw + (u16)((num + den / 2) / den);
+ }
+ }
+ return bf_fader_curve[ARRAY_SIZE(bf_fader_curve) - 1].raw;
+}
+
+/* MIX-mode VU display law — monitoring dB×2 → the 0x1A 0x000A display
+ * value. Piecewise-linear through the captured (dB, display) points
+ * (cap_mix.pcap 2026-08-23: (−62,0) (−54,1) (−48,2) (−42.5,3)
+ * (−35,4) (−28.4,5); cap_panel.pcap: (−7.4,10) (−6.7,11)
+ * (−4.6,12)) — a log-ish VU scale (coarse at the bottom, ~1.4 dB/step
+ * near 0). The −28..−8 dB middle is interpolated; the exact law is
+ * pending the cap_mixdisp.pcap full-range sweep (TODO 0g).
+ */
+static int bf_mix_display(int db2)
+{
+ static const struct {
+ s16 db2;
+ u8 disp;
+ } pts[] = {
+ { -124, 0 }, { -108, 1 }, { -96, 2 }, { -85, 3 },
+ { -70, 4 }, { -57, 5 }, { -15, 10 }, { -13, 11 },
+ { -9, 12 },
+ };
+ int i;
+
+ if (db2 <= pts[0].db2)
+ return 0;
+ for (i = 0; i < ARRAY_SIZE(pts) - 1; i++) {
+ if (db2 <= pts[i + 1].db2) {
+ u32 num = (u32)(db2 - pts[i].db2) *
+ (u32)(pts[i + 1].disp - pts[i].disp);
+ u32 den = pts[i + 1].db2 - pts[i].db2;
+
+ return pts[i].disp + (int)((num + den / 2) / den);
+ }
+ }
+ /* Above −4.6 dB: keep the last slope (2 dB/step) up to +6 dB. */
+ return pts[ARRAY_SIZE(pts) - 1].disp +
+ clamp((db2 - pts[ARRAY_SIZE(pts) - 1].db2) / 4, 0, 12);
+}
+
+/* The kernel driver plays the TotalMix role for the MIX button (the
+ * standalone emulator is hardware-validated in tuxmix-core/src/panel.rs
+ * + usb.rs): one wheel click in fader mode = ±0.5 dB on the SELECT-
+ * chosen channel(s) of the IN-selected pair, into the OUT-selected
+ * output's crosspoint block — the STANDARD map only (cap_mix.pcap /
+ * cap_select2.pcap, no low-map mirror). Mirrors the change into the
+ * xpoint cache so the ALSA controls follow the wheel. Takes the mutex
+ * (the 0x12 writes cycle the transaction flag like the mixer puts).
+ */
+static void bf_panel_mix_wheel(struct snd_usb_babyface *chip, int delta)
+{
+ /* Canonical output of the OUT selection (enum 1 = Ch1/2,
+ * 2 = Phones, 3 = Opt): AN1/2, PH3/4, ADAT7/8 (the optical
+ * output) respectively.
+ */
+ int out = chip->panel_out == 3 ? 5 :
+ chip->panel_out == 2 ? 1 : 0;
+ unsigned int blk = bf_xpoint_block[out];
+ u8 targets[2];
+ int n = 0;
+ int db2;
+ u16 raw, flag;
+ int i;
+
+ /* SELECT-chosen channel(s) of the IN pair (manual §5.1: SELECT
+ * steps left/right/both; none = nothing selected = no-op wheel).
+ * Source indices: AN1/AN2 = 0/1, AN3/AN4 = 2/3, AS1/2 = 4.
+ */
+ if (chip->panel_in == 3) {
+ targets[0] = 4; /* Opt: the AS1/2 pair */
+ n = 1;
+ } else if (chip->panel_select != 3) {
+ int base = chip->panel_in == 2 ? 2 : 0;
+
+ targets[0] = base + (chip->panel_select == 1 ? 1 : 0);
+ n = 1;
+ if (chip->panel_select == 2)
+ targets[n++] = base + 1;
+ }
+
+ mutex_lock(&chip->mutex);
+ db2 = bf_fader_raw_to_db2(chip->panel_mix_raw);
+ db2 = clamp(db2 + delta, BF_FADER_DB2_INF, 12);
+ raw = bf_fader_db2_to_raw(db2);
+ chip->panel_mix_raw = raw;
+ for (i = 0; i < n; i++) {
+ const struct bf_source *s = &bf_sources[targets[i]];
+
+ flag = bf_flag_cycle[chip->flag_cnt];
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+ bf_vendor_write(chip, BF_REQ_CROSSPOINT, raw,
+ (BF_REG_CROSS_BASE_L + BF_REG_CROSS_STRIDE * blk +
+ s->idx_l) | flag);
+ bf_vendor_write(chip, BF_REQ_CROSSPOINT, raw,
+ (BF_REG_CROSS_BASE_R + BF_REG_CROSS_STRIDE * blk +
+ s->idx_r) | flag);
+ chip->xpoint[out][targets[i]][0] = raw;
+ chip->xpoint[out][targets[i]][1] = raw;
+ /* MIX-mode VU display shadow (0x1A 0x000A+mic): TotalMix
+ * mirrors the monitoring level into the panel display family
+ * (cap_mix/cap_panel.pcap) — the input VU segments follow it.
+ * Written only on change (the captures show TotalMix updating
+ * it on segment crossings). Law = bf_mix_display (TODO 0g
+ * pending the exact full-range capture).
+ */
+ if (targets[i] < 4) {
+ int disp = bf_mix_display(db2);
+
+ if (disp != chip->panel_mix_disp[targets[i]]) {
+ bf_vendor_write(chip, BF_REQ_GAIN,
+ (u16)disp,
+ BF_REG_PANEL_GAIN + targets[i]);
+ chip->panel_mix_disp[targets[i]] = disp;
+ }
+ }
+ }
+ mutex_unlock(&chip->mutex);
+}
+
+/* Write an output's L/R masters (8-bit companions + 16-bit with the
+ * transaction flag) and mirror into the cache — shared by the OUT
+ * volume wheel and the balance wheel. Caller holds the mutex.
+ */
+static void bf_panel_write_master(struct snd_usb_babyface *chip, int out,
+ u16 l, u16 r)
+{
+ u16 flag;
+
+ flag = bf_flag_cycle[chip->flag_cnt];
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+ bf_vendor_write(chip, BF_REQ_GAIN, bf_master_8bit(l),
+ BF_REG_MASTER_8 + 2 * out);
+ bf_vendor_write(chip, BF_REQ_GAIN, bf_master_8bit(r),
+ BF_REG_MASTER_8 + 2 * out + 1);
+ bf_vendor_write(chip, BF_REQ_CROSSPOINT, l,
+ (BF_REG_MASTER_16 + 2 * out) | flag);
+ bf_vendor_write(chip, BF_REQ_CROSSPOINT, r,
+ (BF_REG_MASTER_16 + 2 * out + 1) | flag);
+ chip->master[out][0] = l;
+ chip->master[out][1] = r;
+ chip->muted[out] = false;
+ /* A Phones change while DIM is engaged re-bases the restore. */
+ if (chip->dim && out == 1) {
+ chip->dim_saved[0] = l;
+ chip->dim_saved[1] = r;
+ }
+}
+
+/* OUT-mode wheel: the master fader of the OUT-selected output, ±0.5 dB
+ * per click (cap_set2/cap_dim.pcap: the wheel writes the 16-bit master
+ * 0x03E0+2·out on the master curve 0x2000·2^(dB/6); the driver keeps
+ * the 8-bit companion in sync like bf_master_put — the 8-bit is the
+ * real volume). BOTH sides move by the same dB so an existing
+ * balance (hold-SELECT) is preserved. Same output mapping as the MIX
+ * wheel (Phones = canon 1, Opt = ADAT7/8 = canon 5, else AN1/2).
+ */
+static void bf_panel_out_wheel(struct snd_usb_babyface *chip, int delta)
+{
+ int out = chip->panel_out == 3 ? 5 :
+ chip->panel_out == 2 ? 1 : 0;
+ int hl, hr;
+ u16 l, r;
+
+ mutex_lock(&chip->mutex);
+ hl = bf_master_half_db(chip->master[out][0]) + delta;
+ hr = bf_master_half_db(chip->master[out][1]) + delta;
+ l = bf_master_16bit(clamp(hl, -128, 12));
+ r = bf_master_16bit(clamp(hr, -128, 12));
+ bf_panel_write_master(chip, out, l, r);
+ mutex_unlock(&chip->mutex);
+}
+
+/* IN-mode wheel: the gain of the SELECT-chosen channel(s) of the
+ * IN-selected pair, ±1 dB per click (manual §5.1: SELECT steps
+ * left/right/both, then the wheel changes the gain). Writes the PANEL
+ * gain registers 0x1A 0x000A+mic (cap_select.pcap 2026-08-24 — the
+ * "ADC gain" family, which drives the same preamp as the GUI
+ * 0x0000+mic; the cache tracks the raw either way). Opt has no
+ * preamp and SELECT None = no target.
+ */
+static void bf_panel_gain_wheel(struct snd_usb_babyface *chip, int delta)
+{
+ u8 mics[2];
+ int n = 0;
+ int i;
+
+ if (chip->panel_in == 3 || chip->panel_select == 3)
+ return;
+ {
+ int base = chip->panel_in == 2 ? 2 : 0;
+
+ mics[0] = base + (chip->panel_select == 1 ? 1 : 0);
+ n = 1;
+ if (chip->panel_select == 2)
+ mics[n++] = base + 1;
+ }
+
+ mutex_lock(&chip->mutex);
+ for (i = 0; i < n; i++) {
+ int mic = mics[i];
+ int db = clamp((int)chip->gain[mic] + delta,
+ 0, bf_gain_max_db(mic));
+ u8 raw = bf_gain_raw(mic, db);
+
+ bf_vendor_write(chip, BF_REQ_GAIN, raw, BF_REG_PANEL_GAIN + mic);
+ chip->gain[mic] = db;
+ }
+ mutex_unlock(&chip->mutex);
+}
+
+/* OUT-balance wheel (hold SELECT + wheel — manual §5.1 "Output
+ * Balance"): moves the stereo image of the OUT-selected output by
+ * attenuating ONE side, linear in raw (cap_pan_stereo.pcap: the varied
+ * side = fixed·(1−|pan|), ~0x9C raw step per click at 0 dB — the PAN
+ * of the stereo hardware output in TotalMix). The balance position is
+ * derived from the L/R master ratio (the louder side is the fixed
+ * one), so the gesture needs no extra state — and the OUT wheel below
+ * moves both sides by the same dB to preserve an existing balance.
+ */
+static void bf_panel_balance_wheel(struct snd_usb_babyface *chip, int delta)
+{
+ int out = chip->panel_out == 3 ? 5 :
+ chip->panel_out == 2 ? 1 : 0;
+ u16 l = chip->master[out][0];
+ u16 r = chip->master[out][1];
+ int bal; /* −100..+100; + = image right (left varies) */
+ u16 fixed, varied;
+
+ mutex_lock(&chip->mutex);
+ /* Balance from the L/R ratio: the louder side is the fixed one. */
+ if (l >= r) {
+ bal = r ? -(100 - (100 * r) / l) : -100;
+ fixed = l;
+ } else {
+ bal = l ? (100 - (100 * l) / r) : 100;
+ fixed = r;
+ }
+ bal = clamp(bal + delta * 2, -100, 100);
+ varied = (u16)((u32)fixed * (100 - abs(bal)) / 100);
+ l = bal >= 0 ? varied : fixed;
+ r = bal >= 0 ? fixed : varied;
+
+ bf_panel_write_master(chip, out, l, r);
+ mutex_unlock(&chip->mutex);
+}
+
+/* SET press (byte3 0x42 flash): toggle 48V phantom on the
+ * SELECT-chosen mic(s) of the IN-selected pair. The hardware only
+ * does this in standalone mode (online, TotalMix ignores SET — no USB
+ * write in the captures), but the driver IS the host: it writes the
+ * preamp state itself and the P48 LEDs follow (the tuxmix-core
+ * emulator, hardware-verified). Restricted to IN mode + Ch1/2 (the
+ * phantom-capable pair); Opt/Ch3/4 and SELECT None = no target.
+ */
+static void bf_panel_set_phantom(struct snd_usb_babyface *chip)
+{
+ u16 bits = 0;
+ int m;
+
+ if (chip->panel_mix || chip->panel_in != 1 ||
+ chip->panel_select == 3)
+ return;
+ if (chip->panel_select != 1)
+ bits |= BF_PREAMP_48V_MIC1;
+ if (chip->panel_select != 0)
+ bits |= BF_PREAMP_48V_MIC2;
+
+ mutex_lock(&chip->mutex);
+ /* One channel selected: toggle it. Both selected: ALIGN both to
+ * the same state, so repeated SET presses cycle all-on <-> all-off
+ * (a mixed phantom state cannot persist with both selected).
+ */
+ if (chip->panel_select == 2) {
+ if ((chip->preamp & bits) == bits)
+ chip->preamp &= ~bits;
+ else
+ chip->preamp |= bits;
+ } else {
+ chip->preamp ^= bits;
+ }
+ bf_preamp_state_write(chip);
+ for (m = 0; m < 4; m++)
+ chip->panel_mix_disp[m] = 0;
+ mutex_unlock(&chip->mutex);
+}
+
+static void bf_panel_notify(struct snd_usb_babyface *chip, int ctl)
+{
+ if (chip->panel_kctl[ctl])
+ snd_ctl_notify(chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
+ &chip->panel_kctl[ctl]->id);
+}
+
+/* One 0x17 read + decode. Called from the poll work; no locking needed —
+ * the worker is the only writer and the control get callbacks run under
+ * the ALSA controls lock (chip->panel_button/wheel are consumed there).
+ */
+static void bf_panel_tick(struct snd_usb_babyface *chip)
+{
+ u8 st[4];
+ int delta, in, out;
+ bool dim;
+ u8 cls, pcls;
+ int btn;
+ bool mix_flash, fader_now;
+
+ if (bf_vendor_read(chip, BF_REQ_PREAMP, BF_REG_PANEL_READ, st) < 0)
+ return; /* device gone / busy — retry next tick */
+
+ if (!chip->panel_seen) {
+ chip->panel_seen = true;
+ memcpy(chip->panel_prev, st, sizeof(st));
+ /* Seed the state controls from the first snapshot. */
+ in = bf_panel_in_decode((st[2] >> BF_PANEL_IN_SHIFT) & 0x7);
+ if (in)
+ chip->panel_in = in;
+ out = bf_panel_out_decode(st[1] & 0x07);
+ if (out)
+ chip->panel_out = out;
+ chip->panel_mix = !!(st[0] & 0x80);
+ chip->panel_saw_fader = (st[2] >> 4) == 0x0;
+ chip->panel_dim = !!(st[1] & 0x20);
+ return;
+ }
+
+ /* The udev alsactl restore (~100 ms after probe) clobbers the host
+ * SELECT with a stale stored value (the control is VOLATILE but
+ * this alsactl stores/restores it anyway) — re-assert the device's
+ * power-on state (nothing selected, cycle ARMED) for the first
+ * ~3 s so the boot always starts in sync.
+ */
+ if (time_is_after_jiffies(chip->panel_start + 3 * HZ))
+ chip->panel_select = 3;
+
+ /* Button flash (byte3 over the 0x40 idle base). */
+ btn = bf_panel_button_decode(st[3]);
+ if (btn)
+ chip->panel_button = btn;
+
+ /* Wheel: signed 4-bit wrap delta of the byte2 low nibble — only
+ * while the mode class is unchanged. A mode switch (IN 0x4x →
+ * fader 0x0x on a MIX press, or the OUT counter carrying 0x8F →
+ * 0x90 — the OUT counter is a full byte, cap_set2.pcap) must not
+ * be read as a wheel jump. Class: 0 = fader (0x0x), 1 = OUT
+ * (0x8x/0x9x), 2 = IN (0x4x/0x5x/0x6x).
+ */
+ cls = (st[2] >> 4) == 0x8 || (st[2] >> 4) == 0x9 ? 1 :
+ (st[2] >> 4) == 0x0 ? 0 : 2;
+ pcls = (chip->panel_prev[2] >> 4) == 0x8 ||
+ (chip->panel_prev[2] >> 4) == 0x9 ? 1 :
+ (chip->panel_prev[2] >> 4) == 0x0 ? 0 : 2;
+ delta = (int)(st[2] & 0x0f) - (int)(chip->panel_prev[2] & 0x0f);
+ if (delta > 8)
+ delta -= 16;
+ else if (delta < -8)
+ delta += 16;
+ if (delta && cls == pcls) {
+ chip->panel_wheel = clamp(chip->panel_wheel + delta,
+ SHRT_MIN, SHRT_MAX);
+ bf_panel_notify(chip, BF_PANEL_KCTL_WHEEL);
+ /* Wheel by mode (LINUX-VALIDATION §12, the TotalMix
+ * emulator): MIX → monitoring level, OUT (0x8x/0x9x) → the
+ * selected output master (or its balance while SELECT is
+ * held), IN (0x4x/0x5x/0x6x) → the SELECT-chosen preamp
+ * gain.
+ */
+ if (chip->panel_mix)
+ bf_panel_mix_wheel(chip, delta);
+ else if (chip->panel_sel_hold >= 10 && cls == 1)
+ bf_panel_balance_wheel(chip, delta);
+ else if (cls == 1)
+ bf_panel_out_wheel(chip, delta);
+ else if (cls == 2)
+ bf_panel_gain_wheel(chip, delta);
+ }
+
+ /* Selections — keep the previous when the field is not in range
+ * (the fader-mode readback drops the IN position bits).
+ */
+ in = bf_panel_in_decode((st[2] >> BF_PANEL_IN_SHIFT) & 0x7);
+ if (in && in != chip->panel_in) {
+ chip->panel_in = in;
+ /* The card CLEARS its L/R/both selection on an IN pair
+ * switch (user-verified 2026-08-27): re-sync the host-
+ * tracked SELECT so SET / the wheel / MIX target nothing
+ * until the user picks a channel again. This is the main
+ * anti-desync hook (the physical state is not readable).
+ */
+ if (chip->panel_select != 3) {
+ chip->panel_select = 3;
+ bf_panel_notify(chip, BF_PANEL_KCTL_SELECT);
+ }
+ /* An IN-pair switch disarms the device's SELECT cycle: the
+ * next press only re-arms it (no step), the one after that
+ * cycles (device behavior, user-verified 2026-08-28).
+ */
+ chip->panel_select_armed = false;
+ bf_panel_notify(chip, BF_PANEL_KCTL_IN);
+ }
+ out = bf_panel_out_decode(st[1] & 0x07);
+ if (out && out != chip->panel_out) {
+ chip->panel_out = out;
+ bf_panel_notify(chip, BF_PANEL_KCTL_OUT);
+ }
+
+ /* SELECT press cycles the channel selection L → R → both → none
+ * → L (manual §5.1). The state is NOT in the readback
+ * (panelprobe 2026-08-24), so it is tracked host-side.
+ */
+ if (st[3] == BF_PANEL_FLASH_SELECT &&
+ chip->panel_prev[3] != BF_PANEL_FLASH_SELECT) {
+ if (!chip->panel_select_armed) {
+ /* Disarmed (IN switch since the last step): the press
+ * only re-arms the cycle — the device steps on the
+ * NEXT press (user-verified 2026-08-28).
+ */
+ chip->panel_select_armed = true;
+ } else {
+ chip->panel_select = (chip->panel_select + 1) & 3;
+ }
+ bf_panel_notify(chip, BF_PANEL_KCTL_SELECT);
+ }
+ /* SELECT hold (the OUT-balance gesture, manual §5.1 "Output
+ * Balance"): a tap flashes byte3 0x50 for ~2-3 frames at 20 Hz
+ * (~100-150 ms — selhold_probe2), a hold keeps it sustained, and
+ * byte0 does NOT gain the 0x80 engaged bit — so the duration is
+ * the only discriminator: >= 10 ticks (200 ms at 50 Hz) = held.
+ */
+ if (st[3] == BF_PANEL_FLASH_SELECT)
+ chip->panel_sel_hold++;
+ else
+ chip->panel_sel_hold = 0;
+
+ /* SET (A) press: host-side 48V phantom toggle on the
+ * SELECT-chosen mic(s) (see bf_panel_set_phantom).
+ */
+ if (st[3] == BF_PANEL_FLASH_SET &&
+ chip->panel_prev[3] != BF_PANEL_FLASH_SET)
+ bf_panel_set_phantom(chip);
+
+ /* MIX (fader mode) — HOST-latched, like TotalMix (cap_mix.pcap,
+ * cap_select2.pcap): the raw press readback is `0D 0D 41 44` —
+ * byte3 flash 0x44, NO engaged bit, byte2 still in the current
+ * mode. The host acks the flash with `0x17 0x8480 0x8C80` → the
+ * device latches fader mode (byte0/1 gain the 0x80 bit, byte2 =
+ * 0x00+n counter) and STAYS there after the physical release; the
+ * SECOND 0x44 flash exits it (`0x17 0x0400 0x8000` + `0x8080`).
+ * A mode button (IN/OUT/SET) pressed during MIX makes the device
+ * leave fader mode by itself → same exit writes (the user: IN
+ * must return to gain control). `panel_saw_fader` gates the
+ * device-driven exit so a pre-ack readback (byte2 still 0x4x
+ * while the 0x44 flash shows) never ends MIX before it started.
+ */
+ mix_flash = st[3] == BF_PANEL_FLASH_MIX &&
+ chip->panel_prev[3] != BF_PANEL_FLASH_MIX;
+ fader_now = (st[2] >> 4) == 0x0;
+
+ if (mix_flash) {
+ if (chip->panel_mix) {
+ bf_vendor_write(chip, BF_REQ_PREAMP, 0x0400, 0x8000);
+ bf_vendor_write(chip, BF_REQ_PREAMP, 0x0400, 0x8080);
+ chip->panel_mix = false;
+ chip->panel_saw_fader = false;
+ } else {
+ int ref, out;
+ int m;
+
+ bf_vendor_write(chip, BF_REQ_PREAMP, 0x8480, 0x8c80);
+ chip->panel_mix = true;
+ /* Seed the monitoring level at the reference
+ * crosspoint's current value so the first wheel
+ * click doesn't jump from −inf (the reference =
+ * the first SELECT-chosen channel of the IN pair;
+ * Opt = the AS1/2 pair).
+ */
+ out = chip->panel_out == 3 ? 5 :
+ chip->panel_out == 2 ? 1 : 0;
+ ref = chip->panel_in == 3 ? 4 :
+ (chip->panel_in == 2 ? 2 : 0) +
+ (chip->panel_select == 1 ? 1 : 0);
+ chip->panel_mix_raw = chip->xpoint[out][ref][0];
+ /* Seed the VU display shadow at the CURRENT level
+ * (cap_panel.pcap: TotalMix writes the display value of
+ * the current fader on engage — 10 in that session —
+ * not a hard 0; cap_mix's 0 was because the fader sat
+ * at the bottom). Only the channels the wheel can move.
+ */
+ for (m = 0; m < 4; m++)
+ chip->panel_mix_disp[m] = 0;
+ if (ref < 4) {
+ int db2 = bf_fader_raw_to_db2(chip->panel_mix_raw);
+ int disp = bf_mix_display(db2);
+
+ bf_vendor_write(chip, BF_REQ_GAIN, (u16)disp,
+ BF_REG_PANEL_GAIN + ref);
+ chip->panel_mix_disp[ref] = disp;
+ }
+ }
+ bf_panel_notify(chip, BF_PANEL_KCTL_MIX);
+ }
+ if (fader_now) {
+ chip->panel_saw_fader = true;
+ } else if (chip->panel_mix && chip->panel_saw_fader &&
+ st[3] != BF_PANEL_FLASH_MIX) {
+ /* device left fader mode by itself (IN/OUT/SET press) */
+ bf_vendor_write(chip, BF_REQ_PREAMP, 0x0400, 0x8000);
+ bf_vendor_write(chip, BF_REQ_PREAMP, 0x0400, 0x8080);
+ chip->panel_mix = false;
+ chip->panel_saw_fader = false;
+ bf_panel_notify(chip, BF_PANEL_KCTL_MIX);
+ }
+
+ dim = !!(st[1] & 0x20);
+ if (dim != chip->panel_dim) {
+ chip->panel_dim = dim;
+ bf_panel_notify(chip, BF_PANEL_KCTL_DIM);
+ }
+
+ memcpy(chip->panel_prev, st, sizeof(st));
+}
+
+void babyface_panel_work(struct work_struct *work)
+{
+ struct snd_usb_babyface *chip = container_of(work,
+ struct snd_usb_babyface, panel_work.work);
+
+ if (chip->shutdown)
+ return;
+ bf_panel_tick(chip);
+ schedule_delayed_work(&chip->panel_work,
+ msecs_to_jiffies(chip->panel_poll_ms));
+}
+
+void babyface_panel_start(struct snd_usb_babyface *chip)
+{
+ chip->panel_seen = false;
+ /* The device boots with NOTHING selected (the SELECT cycle starts
+ * at none → AN1 → AN2 → both → none) — the unreadable selection
+ * must start there too, or every later SET is off by one channel
+ * (host at AN1 while the LEDs show nothing → first SELECT makes
+ * the device blink AN1 but the host believes AN2).
+ */
+ chip->panel_select = 3; /* none */
+ chip->panel_select_armed = true;
+ chip->panel_start = jiffies;
+ schedule_delayed_work(&chip->panel_work, 0);
+}
+
+void babyface_panel_stop(struct snd_usb_babyface *chip)
+{
+ cancel_delayed_work_sync(&chip->panel_work);
+}
+
+/* ── controls ────────────────────────── */
+
+/* The button/wheel controls hold the LATEST state and are NOT consumed
+ * on read: wireplumber subscribes to every notifying control and reads
+ * it, so a clear-on-get would let another reader eat the event. Each
+ * consumer tracks its own baseline and acts on changes (the button is a
+ * last-press code, the wheel an accumulated signed delta). VOLATILE
+ * keeps alsactl from caching them.
+ */
+static int bf_panel_button_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+ uinfo->count = 1;
+ uinfo->value.integer.min = 0;
+ uinfo->value.integer.max = BF_PANEL_BTN_DIM;
+ uinfo->value.integer.step = 1;
+ return 0;
+}
+
+static int bf_panel_button_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+
+ ucontrol->value.integer.value[0] = chip->panel_button;
+ return 0;
+}
+
+static int bf_panel_wheel_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+ uinfo->count = 1;
+ uinfo->value.integer.min = SHRT_MIN;
+ uinfo->value.integer.max = SHRT_MAX;
+ uinfo->value.integer.step = 1;
+ return 0;
+}
+
+static int bf_panel_wheel_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+
+ ucontrol->value.integer.value[0] = chip->panel_wheel;
+ return 0;
+}
+
+static int bf_panel_in_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ return snd_ctl_enum_info(uinfo, 1, 4, bf_panel_in_texts);
+}
+
+static int bf_panel_in_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+
+ ucontrol->value.enumerated.item[0] = chip->panel_in;
+ return 0;
+}
+
+static int bf_panel_out_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ return snd_ctl_enum_info(uinfo, 1, 4, bf_panel_out_texts);
+}
+
+static int bf_panel_out_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+
+ ucontrol->value.enumerated.item[0] = chip->panel_out;
+ return 0;
+}
+
+static int bf_panel_select_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ return snd_ctl_enum_info(uinfo, 1, 4, bf_panel_select_texts);
+}
+
+static int bf_panel_select_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+
+ ucontrol->value.enumerated.item[0] = chip->panel_select;
+ return 0;
+}
+
+/* Writable so software (or the user, after a driver reload) can
+ * re-sync the host-tracked SELECT state to the physical card — the
+ * L/R/both/none state is NOT in the 0x17 readback, so a reload starts
+ * at "Left" while the card may sit at any position; a desync makes
+ * SET / the wheel / MIX target the wrong channel. Writing the
+ * physical state re-aligns the emulation (TotalMix parity: it also
+ * lets software select channels directly).
+ */
+static int bf_panel_select_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ unsigned int v = ucontrol->value.enumerated.item[0];
+ int ret = 0;
+
+ if (v > 3)
+ return -EINVAL;
+ if (v != chip->panel_select) {
+ chip->panel_select = v;
+ bf_panel_notify(chip, BF_PANEL_KCTL_SELECT);
+ ret = 1;
+ }
+ return ret;
+}
+
+/* Shared boolean get — private_value selects mix (0) / dim (1). */
+static int bf_panel_bool_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+
+ ucontrol->value.integer.value[0] =
+ kctl->private_value ? chip->panel_dim : chip->panel_mix;
+ return 0;
+}
+
+int babyface_create_panel(struct snd_usb_babyface *chip)
+{
+ struct snd_kcontrol *kctl;
+ int err;
+
+ memset(chip->panel_kctl, 0, sizeof(chip->panel_kctl));
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Front Panel Button",
+ .access = SNDRV_CTL_ELEM_ACCESS_READ |
+ SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+ .info = bf_panel_button_info,
+ .get = bf_panel_button_get,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+ chip->panel_kctl[BF_PANEL_KCTL_BUTTON] = kctl;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Front Panel Wheel",
+ .access = SNDRV_CTL_ELEM_ACCESS_READ |
+ SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+ .info = bf_panel_wheel_info,
+ .get = bf_panel_wheel_get,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+ chip->panel_kctl[BF_PANEL_KCTL_WHEEL] = kctl;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Front Panel In",
+ .access = SNDRV_CTL_ELEM_ACCESS_READ |
+ SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+ .info = bf_panel_in_info,
+ .get = bf_panel_in_get,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+ chip->panel_kctl[BF_PANEL_KCTL_IN] = kctl;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Front Panel Out",
+ .access = SNDRV_CTL_ELEM_ACCESS_READ |
+ SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+ .info = bf_panel_out_info,
+ .get = bf_panel_out_get,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+ chip->panel_kctl[BF_PANEL_KCTL_OUT] = kctl;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Front Panel Mix",
+ .access = SNDRV_CTL_ELEM_ACCESS_READ |
+ SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+ .info = snd_ctl_boolean_mono_info,
+ .get = bf_panel_bool_get,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+ chip->panel_kctl[BF_PANEL_KCTL_MIX] = kctl;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Front Panel Dim",
+ .access = SNDRV_CTL_ELEM_ACCESS_READ |
+ SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+ .info = snd_ctl_boolean_mono_info,
+ .get = bf_panel_bool_get,
+ .private_value = 1,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+ chip->panel_kctl[BF_PANEL_KCTL_DIM] = kctl;
+
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "Front Panel Select",
+ .access = SNDRV_CTL_ELEM_ACCESS_READ |
+ SNDRV_CTL_ELEM_ACCESS_WRITE |
+ SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+ .info = bf_panel_select_info,
+ .get = bf_panel_select_get,
+ .put = bf_panel_select_put,
+ }, chip);
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+ chip->panel_kctl[BF_PANEL_KCTL_SELECT] = kctl;
+
+ return 0;
+}
+
+#define BF_EQ_Q27 (1 << 27)
+#define BF_EQ_LC_OFF 0x04000000
+#define BF_EQ_BLOCK_LEN 64
+
+/* atan(2^-i) x 2^27 (CORDIC). */
+static const s64 bf_atan_tab[28] = {
+ 0x6487ED5, 0x3B58CE1, 0x1F5B760, 0xFEADD5,
+ 0x7FD56F, 0x3FFAAB, 0x1FFF55, 0xFFFEB,
+ 0x7FFFD, 0x40000, 0x20000, 0x10000,
+ 0x8000, 0x4000, 0x2000, 0x1000,
+ 0x800, 0x400, 0x200, 0x100,
+ 0x80, 0x40, 0x20, 0x10,
+ 0x8, 0x4, 0x2, 0x1,
+};
+
+/* ---- fixed-point helpers (Q27 in/out, s64 intermediates) ---- */
+
+/* sin/cos of an angle in [0, pi/2] (Q27). Simultaneous CORDIC, 28
+ * iterations (~1e-8 residual). eq_selftest.c verifies the whole
+ * pipeline against the double-precision reference.
+ */
+static void bf_sincos(s64 ang, s64 *sn, s64 *cs)
+{
+ s64 x = 0x4DBA76D; /* 1/1.64676 x 2^27 (CORDIC gain) */
+ s64 y = 0;
+ s64 z = ang;
+ int i;
+
+ for (i = 0; i < 28; i++) {
+ s64 d = z >= 0 ? 1 : -1;
+ s64 nx = x - d * (y >> i);
+ s64 ny = y + d * (x >> i);
+
+ x = nx;
+ y = ny;
+ z -= d * bf_atan_tab[i];
+ }
+ *cs = x;
+ *sn = y;
+}
+
+/* 2^u for u in Q27, u in [-2, 2] (gain-amplitude range). */
+static s64 bf_exp2(s64 u)
+{
+ s64 n = u >> 27;
+ s64 r = u - (n << 27);
+ s64 rl = (r * 0x58B90C0 + (1 << 26)) >> 27; /* r.ln2 */
+ s64 e = BF_EQ_Q27;
+ s64 term = BF_EQ_Q27;
+ int k;
+
+ for (k = 1; k <= 10; k++) {
+ term = ((term * rl + (1 << 26)) >> 27) / k;
+ e += term;
+ }
+ return n >= 0 ? e << n : e >> -n;
+}
+
+/* The 5 stored words (c0..c3 + shared c4) for one band.
+ * type: 1 bell, 2 low shelf, 3 high shelf. freq_hz, fs in Hz;
+ * q100 = Q x 100; gain_x10 = dB x 10. fs is the stream rate.
+ */
+void bf_eq_band_words(s32 *w, int type, s32 freq_hz, s32 q100,
+ s32 gain_x10, s32 fs)
+{
+ s64 f = freq_hz;
+ s64 w0, c, s, alpha, A, sq;
+ s64 b0, b1, b2, a0, a1, a2;
+ s64 pi = 0x1921FB54; /* pi, Q27 */
+ s64 hpi = 0xC90FDAA; /* pi/2, Q27 */
+ s64 t;
+ int both = 0, cflip = 0;
+
+ if (gain_x10 == 0 || q100 <= 0) {
+ /* Inactive band: identity words (also guards the alpha
+ * division below against the default Q=0 the controls start
+ * with — a user setting gain before Q used to hit a kernel
+ * divide-by-zero oops).
+ */
+ w[0] = 0;
+ w[1] = 0;
+ w[2] = 0;
+ w[3] = 0;
+ return;
+ }
+
+ /* w0 = 2.pi.f/fs (Q27), reduced to [0, pi/2]. */
+ w0 = (f * BF_EQ_Q27) / fs;
+ w0 = (w0 * 0x3243F6A9) >> 27; /* x 2.pi */
+ t = w0;
+ if (t > pi) {
+ t -= pi;
+ both = 1;
+ }
+ if (t > hpi) {
+ t = pi - t;
+ cflip = 1;
+ }
+ bf_sincos(t, &s, &c);
+ if (both) {
+ s = -s;
+ c = -c;
+ }
+ if (cflip)
+ c = -c;
+
+ alpha = (s * 100 + q100) / (2 * (s64)q100); /* sin(w0)/(2Q) */
+ /* A = 10^(g/40), sqrt(A): g = gain_x10/10 dB */
+ A = bf_exp2((s64)gain_x10 * 0x11021E);
+ sq = bf_exp2((s64)gain_x10 * 0x8810F);
+
+ if (type == 1) {
+ s64 ta = (alpha * A + (1 << 26)) >> 27;
+
+ b0 = BF_EQ_Q27 + ta;
+ b1 = -2 * c;
+ b2 = BF_EQ_Q27 - ta;
+ a0 = BF_EQ_Q27 + (alpha * BF_EQ_Q27 + A / 2) / A;
+ a1 = -2 * c;
+ a2 = BF_EQ_Q27 - (alpha * BF_EQ_Q27 + A / 2) / A;
+ } else {
+ s64 ap1 = A + BF_EQ_Q27;
+ s64 am1 = A - BF_EQ_Q27;
+ s64 cp0 = (am1 * c + (1 << 26)) >> 27; /* (A-1).c */
+ s64 cp1 = (ap1 * c + (1 << 26)) >> 27; /* (A+1).c */
+ s64 ab = (2 * sq * alpha + (1 << 26)) >> 27;
+
+ if (type == 2) { /* low shelf */
+ b0 = (A * (ap1 - cp0 + ab) + (1 << 26)) >> 27;
+ b1 = (2 * A * (am1 - cp1) + (1 << 26)) >> 27;
+ b2 = (A * (ap1 - cp0 - ab) + (1 << 26)) >> 27;
+ a0 = ap1 + cp0 + ab;
+ a1 = -2 * (am1 + cp1);
+ a2 = ap1 + cp0 - ab;
+ } else { /* high shelf */
+ b0 = (A * (ap1 + cp0 + ab) + (1 << 26)) >> 27;
+ b1 = (-2 * A * (am1 + cp1) + (1 << 26)) >> 27;
+ b2 = (A * (ap1 + cp0 - ab) + (1 << 26)) >> 27;
+ a0 = ap1 - cp0 + ab;
+ a1 = -2 * (am1 - cp1);
+ a2 = ap1 - cp0 - ab;
+ }
+ }
+
+ w[0] = (s32)((a1 * BF_EQ_Q27 + a0 / 2) / a0);
+ w[1] = (s32)((a2 * BF_EQ_Q27 + a0 / 2) / a0);
+ w[2] = (s32)((b1 * BF_EQ_Q27 + b0 / 2) / b0);
+ w[3] = (s32)((b2 * BF_EQ_Q27 + b0 / 2) / b0);
+ w[4] = (s32)((b0 * BF_EQ_Q27 + a0 / 2) / a0);
+}
+
+/* ---- low cut ---- */
+
+/* Slope byte: 2^n-1 (n poles) -> 6/12/18/24 dB per oct; 0 = off. */
+static u8 bf_eq_lc_slope_byte(s32 slope_db)
+{
+ switch (slope_db) {
+ case 6: return 0x01;
+ case 12: return 0x03;
+ case 18: return 0x07;
+ case 24: return 0x0F;
+ }
+ return 0;
+}
+
+/* The 0x38 low-cut frequency word: round(K.f'.(11656)/(11656+f')) with
+ * K = 11508, f' = f x slope-compensation factor (cap_eq9 fit, 0.003%;
+ * the slope factor keeps the composite -3 dB point constant).
+ */
+static u32 bf_eq_lc_freq_raw(s32 freq_hz, s32 slope_db)
+{
+ s64 f, word;
+
+ if (freq_hz <= 0)
+ return BF_EQ_LC_OFF;
+ f = freq_hz;
+ switch (slope_db) {
+ case 6:
+ f = f * 15267 / 10000;
+ break;
+
+ case 18:
+ f = f * 8061 / 10000;
+ break;
+
+ case 24:
+ f = f * 6977 / 10000;
+ break;
+ }
+ word = (11508 * f * 11656 + (11656 + f) / 2) / (11656 + f);
+ return (u32)word;
+}
+
+/* ---- block build + bulk write ---- */
+
+static void bf_eq_build_block(u8 *b, int ch, u8 slope,
+ const s32 bands[3][4], s32 shared, u32 lc)
+{
+ int slot, k;
+
+ memset(b, 0, BF_EQ_BLOCK_LEN);
+ b[0] = ch;
+ b[1] = slope;
+ b[2] = ch;
+ b[3] = 0x80; /* EQ engine active */
+ for (slot = 0; slot < 3; slot++) {
+ for (k = 0; k < 4; k++) {
+ put_unaligned_le32((u32)bands[slot][k],
+ b + 0x04 + slot * 0x10 + 4 * k);
+ }
+ }
+ put_unaligned_le32((u32)shared, b + 0x34);
+ put_unaligned_le32(lc, b + 0x38);
+}
+
+/* Upload one 64-byte block on bulk OUT ep 0x0A (interface 1). */
+static int bf_eq_upload(struct snd_usb_babyface *chip, const u8 *block)
+{
+ u8 *buf;
+ int ret, len;
+
+ /* usb_bulk_msg DMA-maps the buffer: it must not be on the stack
+ * (usb_hcd_map_urb_for_dma returns -EAGAIN for stack buffers).
+ */
+ buf = kmemdup(block, BF_EQ_BLOCK_LEN, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ ret = usb_bulk_msg(chip->dev, usb_sndbulkpipe(chip->dev, 0x0a),
+ buf, BF_EQ_BLOCK_LEN, &len, 1000);
+ kfree(buf);
+ if (ret < 0)
+ dev_err(&chip->dev->dev, "EQ bulk upload failed: %d\n", ret);
+ return ret;
+}
+
+/* Write the L+R block pair for one strip (channel base = strip x 2). */
+static int bf_eq_write_strip(struct snd_usb_babyface *chip, int strip)
+{
+ struct bf_eq_channel *e = &chip->eq[strip];
+ u8 b[BF_EQ_BLOCK_LEN];
+ s32 identity[3][4] = { { 0 }, { 0 }, { 0 } };
+ s32 shared = e->on ? e->shared : BF_EQ_Q27;
+ u32 lc = e->on ? e->lc_raw : BF_EQ_LC_OFF;
+ /* The header slope byte (b[1]) is only valid while the low cut is
+ * engaged: a stale slope with 0x38 = off made the device apply a
+ * garbage-frequency cut (ear-verified: "low cut off" left only
+ * highs). cap_eq7: byte1 = 0x00 + 0x38 = 0x04000000 when off.
+ */
+ u8 slope = (e->on && e->lc_hz > 0) ? e->slope : 0;
+ int ch, ret;
+
+ for (ch = 0; ch < 2; ch++) {
+ bf_eq_build_block(b, strip * 2 + ch, slope,
+ e->on ? e->words : identity, shared, lc);
+ ret = bf_eq_upload(chip, b);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
+/* Recompute one strip's words + low cut from its params, re-upload.
+ * Lock-free by convention: every caller must already hold chip->mutex
+ * (bf_eq_put() and bf_eq_reupload() do) — asserting it here catches a
+ * future caller that forgets, instead of a silent self-deadlock.
+ */
+static void bf_eq_update_strip(struct snd_usb_babyface *chip, int strip)
+{
+ struct bf_eq_channel *e = &chip->eq[strip];
+ s32 fs = chip->rate ? chip->rate : 48000;
+ s32 last_c4 = BF_EQ_Q27;
+ int band, i;
+
+ lockdep_assert_held(&chip->mutex);
+
+ for (band = 0; band < 3; band++) {
+ s32 w[5];
+
+ bf_eq_band_words(w, e->band_type[band], e->band_freq[band],
+ e->band_q[band], e->band_gain[band], fs);
+ for (i = 0; i < 4; i++)
+ e->words[band][i] = w[i];
+ if (e->band_type[band] && e->band_gain[band])
+ last_c4 = w[4]; /* shared scale: the last band */
+ }
+ e->shared = last_c4;
+ e->lc_raw = bf_eq_lc_freq_raw(e->lc_hz, e->slope_db);
+ e->slope = bf_eq_lc_slope_byte(e->slope_db);
+ bf_eq_write_strip(chip, strip);
+}
+
+/* Recompute + re-upload all four strips (rate change). Caller must
+ * hold chip->mutex — bf_eq_update_strip()/bf_eq_write_strip() are
+ * lock-free by convention (see bf_eq_put()) and the only caller,
+ * babyface_pcm_hw_params(), already holds the lock across the rate
+ * change; locking here too self-deadlocked it (hung-task: "blocked
+ * on a mutex likely owned by" itself, hit via regress.sh's rate
+ * sweep).
+ */
+void bf_eq_reupload(struct snd_usb_babyface *chip)
+{
+ int strip;
+
+ for (strip = 0; strip < 4; strip++)
+ bf_eq_update_strip(chip, strip);
+}
+
+/* ---- ALSA controls (4 strips x 19 controls) ---- */
+
+#define EQ_STRIP(pv) ((pv) >> 8)
+#define EQ_PARAM(pv) ((pv) & 0xff)
+/* params: 0 enable, 1-3 type, 4-6 freq, 7-9 q, 10-12 gain, 13 lc freq, 14 lc slope */
+
+static const char *const bf_eq_type_texts[] = {
+ "Off", "Bell", "Low Shelf", "High Shelf", NULL
+};
+
+static const char *const bf_eq_slope_texts[] = {
+ "6 dB/oct", "12 dB/oct", "18 dB/oct", "24 dB/oct", NULL
+};
+
+static int bf_eq_info(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_info *uinfo)
+{
+ int param = EQ_PARAM(kctl->private_value);
+
+ if (param == 0) {
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
+ uinfo->count = 1;
+ return 0;
+ }
+ if (param == 1 || param == 2 || param == 3)
+ return snd_ctl_enum_info(uinfo, 1, 4, bf_eq_type_texts);
+ if (param == 14)
+ return snd_ctl_enum_info(uinfo, 1, 4, bf_eq_slope_texts);
+
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+ uinfo->count = 1;
+ uinfo->value.integer.min = (param == 10 || param == 11 ||
+ param == 12) ? -240 :
+ (param == 7 || param == 8 ||
+ param == 9) ? 5 : 0;
+ uinfo->value.integer.max = (param == 7 || param == 8 ||
+ param == 9) ? 1000 :
+ (param == 10 || param == 11 ||
+ param == 12) ? 240 : 20000;
+ uinfo->value.integer.step = 1;
+ return 0;
+}
+
+static int bf_eq_get(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ struct bf_eq_channel *e = &chip->eq[EQ_STRIP(kctl->private_value)];
+ int param = EQ_PARAM(kctl->private_value);
+ int band = (param - 1) % 3;
+ s32 *v = NULL;
+
+ switch (param) {
+ case 0:
+ v = (s32 *)&e->on;
+ break;
+
+ case 1:
+ case 2:
+ case 3:
+ v = &e->band_type[band];
+ break;
+
+ case 4:
+ case 5:
+ case 6:
+ v = &e->band_freq[band];
+ break;
+
+ case 7:
+ case 8:
+ case 9:
+ v = &e->band_q[band];
+ break;
+
+ case 10:
+ case 11:
+ case 12:
+ v = &e->band_gain[band];
+ break;
+
+ case 13:
+ v = &e->lc_hz;
+ break;
+
+ case 14:
+ v = &e->slope_db;
+ break;
+ }
+ if (param == 14) {
+ /* Inverse of put's index->dB map: slope_db stores the raw
+ * 6/12/18/24 dB/oct value, but an ENUMERATED control's .get
+ * must return the enum item index (0-3), same as .put
+ * receives — returning the raw dB value here (the bug this
+ * replaces) fed back an out-of-range index to every ALSA
+ * consumer (confirmed via amixer: writing index 1 read back
+ * as value 12, not 1).
+ */
+ s32 slope = v ? *v : 6;
+
+ ucontrol->value.integer.value[0] =
+ slope >= 24 ? 3 : slope >= 18 ? 2 : slope >= 12 ? 1 : 0;
+ } else {
+ ucontrol->value.integer.value[0] = v ? *v : 0;
+ }
+ return 0;
+}
+
+static int bf_eq_put(struct snd_kcontrol *kctl,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_usb_babyface *chip = snd_kcontrol_chip(kctl);
+ int strip = EQ_STRIP(kctl->private_value);
+ int param = EQ_PARAM(kctl->private_value);
+ struct bf_eq_channel *e = &chip->eq[strip];
+ int band = (param - 1) % 3;
+ s32 nv = (s32)ucontrol->value.integer.value[0];
+ s32 *v = NULL;
+ int ret = 0;
+
+ switch (param) {
+ case 0:
+ v = (s32 *)&e->on;
+ break;
+
+ case 1:
+ case 2:
+ case 3:
+ v = &e->band_type[band];
+ break;
+
+ case 4:
+ case 5:
+ case 6:
+ v = &e->band_freq[band];
+ break;
+
+ case 7:
+ case 8:
+ case 9:
+ v = &e->band_q[band];
+ break;
+
+ case 10:
+ case 11:
+ case 12:
+ v = &e->band_gain[band];
+ break;
+
+ case 13:
+ v = &e->lc_hz;
+ break;
+
+ case 14:
+ v = &e->slope_db;
+ break;
+ }
+ if (param == 14) /* slope enum items are 6/12/18/24 */
+ nv = nv == 0 ? 6 : nv == 1 ? 12 : nv == 2 ? 18 : 24;
+
+ mutex_lock(&chip->mutex);
+ if (v && *v != nv) {
+ *v = nv;
+ bf_eq_update_strip(chip, strip);
+ ret = 1;
+ }
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+int babyface_create_eq(struct snd_usb_babyface *chip)
+{
+ static const char *const names[4] = { "AN1", "AN2", "AN3", "AN4" };
+ static const char *const params[] = {
+ "EQ Enable",
+ "EQ Band 1 Type", "EQ Band 2 Type", "EQ Band 3 Type",
+ "EQ Band 1 Freq", "EQ Band 2 Freq", "EQ Band 3 Freq",
+ "EQ Band 1 Q", "EQ Band 2 Q", "EQ Band 3 Q",
+ "EQ Band 1 Gain", "EQ Band 2 Gain", "EQ Band 3 Gain",
+ "EQ Low Cut Freq", "EQ Low Cut Slope",
+ };
+ int strip, i, err;
+
+ for (strip = 0; strip < 4; strip++) {
+ for (i = 0; i < 15; i++) {
+ struct snd_kcontrol *kctl;
+ char name[64];
+
+ snprintf(name, sizeof(name), "%s %s", names[strip],
+ params[i]);
+ kctl = snd_ctl_new1(&(struct snd_kcontrol_new){
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "EQ",
+ .index = 0,
+ .info = bf_eq_info,
+ .get = bf_eq_get,
+ .put = bf_eq_put,
+ .private_value = (strip << 8) | i,
+ }, chip);
+ if (!kctl)
+ return -ENOMEM;
+ strscpy(kctl->id.name, name, sizeof(kctl->id.name));
+ err = snd_ctl_add(chip->card, kctl);
+ if (err < 0)
+ return err;
+ }
+ }
+ return 0;
+}
diff --git a/sound/usb/babyfacepro/babyfacepro.c b/sound/usb/babyfacepro/babyfacepro.c
new file mode 100644
index 000000000..44ad80584
--- /dev/null
+++ b/sound/usb/babyfacepro/babyfacepro.c
@@ -0,0 +1,1449 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * RME Babyface Pro FS — proprietary-mode USB audio driver
+ *
+ * Core driver: USB vendor requests + cold init, interrupt-URB PCM
+ * streaming, mixer-state persistence across re-probes/resume, and
+ * the card lifecycle (probe/disconnect/PM/module entry).
+ *
+ * See babyfacepro.h for the shared device state and register map,
+ * and babyfacepro-ctl.c for the ALSA control surface (mixer, front
+ * panel, DSP EQ).
+ */
+#include <linux/log2.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/unaligned.h>
+#include <linux/usb.h>
+#include <linux/workqueue.h>
+#include <sound/control.h>
+#include <sound/tlv.h>
+#include <sound/core.h>
+#include <sound/initval.h>
+#include <sound/pcm.h>
+
+#include "babyfacepro.h"
+
+/* The transaction-flag counter cycle on 16-bit writes. */
+const u16 bf_flag_cycle[4] = { 0xc000, 0x4000, 0x8000, 0x0000 };
+
+/* ── sample-rate / alt classes ──────────────────── */
+
+static const struct bf_rate bf_rates[] = {
+ { 32000, BF_ALT_1, 56, 8 },
+ { 44100, BF_ALT_1, 56, 8 },
+ { 48000, BF_ALT_1, 56, 8 },
+ { 64000, BF_ALT_1, 56, 8 },
+ { 88200, BF_ALT_1, 56, 8 },
+ { 96000, BF_ALT_2, 40, 16 },
+ { 128000, BF_ALT_2, 40, 16 },
+ { 176400, BF_ALT_3, 32, 32 },
+ { 192000, BF_ALT_3, 32, 32 },
+};
+
+static const unsigned int bf_rate_list[ARRAY_SIZE(bf_rates)] = {
+ 32000, 44100, 48000, 64000, 88200,
+ 96000, 128000, 176400, 192000,
+};
+
+const struct snd_pcm_hw_constraint_list bf_rates_constraint = {
+ .count = ARRAY_SIZE(bf_rate_list),
+ .list = bf_rate_list,
+ .mask = 0,
+};
+
+const struct bf_rate *bf_rate_lookup(unsigned int rate)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(bf_rates); i++)
+ if (bf_rates[i].rate == rate)
+ return &bf_rates[i];
+ return NULL;
+}
+
+/* ── vendor requests ─────────────────────── */
+
+int bf_vendor_write(struct snd_usb_babyface *chip, u8 req, u16 val, u16 idx)
+{
+ return usb_control_msg_send(chip->dev, 0, req,
+ USB_DIR_OUT | USB_TYPE_VENDOR |
+ USB_RECIP_DEVICE,
+ val, idx, NULL, 0, 1000, GFP_KERNEL);
+}
+
+int bf_vendor_read(struct snd_usb_babyface *chip, u8 req, u16 idx, u8 *buf)
+{
+ return usb_control_msg_recv(chip->dev, 0, req,
+ USB_DIR_IN | USB_TYPE_VENDOR |
+ USB_RECIP_DEVICE,
+ 0, idx, buf, 4, 1000, GFP_KERNEL);
+}
+
+/* The cold-start session init (cap_coldplug.pcap), verbatim from the
+ * user-space reference (protocol::streaming_init). Without it the
+ * firmware never validates a stream.
+ */
+int bf_cold_init(struct snd_usb_babyface *chip)
+{
+ int ret, i;
+
+ for (i = 0; i <= 0x3d; i++) {
+ if (i == 0x1e || i == 0x1f)
+ continue;
+ ret = bf_vendor_write(chip, BF_REQ_REG_CLEAR, 0x0000, i);
+ if (ret < 0)
+ return ret;
+ }
+ /* 48-kHz DDS clock quads (banked 0x1B). */
+ ret = bf_vendor_write(chip, BF_REQ_DDS, 0xc350, 0x0000);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_DDS, 0x8db8, 0xd201);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_DDS, 0x8234, 0xd302);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_DDS, 0x7cff, 0xf803);
+ if (ret < 0)
+ return ret;
+ /* 0x1C status — the hardware-validated reference (protocol::
+ * streaming_init) sends it as an OUT write; Windows reads it.
+ * Both are tolerated; match the validated path.
+ */
+ ret = bf_vendor_write(chip, BF_REQ_STATUS_2, 0x0000, 0x0000);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_KEEPALIVE, 0x0021, BF_REG_KEEPALIVE_INIT);
+ if (ret < 0)
+ return ret;
+ /* 0x17 wIdx=0x0000 does NOT touch the preamp state (0x003F). */
+ ret = bf_vendor_write(chip, BF_REQ_PREAMP, 0x000c, 0x0000);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_PREAMP_COMMIT, 0x0000, 0x0000);
+ if (ret < 0)
+ return ret;
+ for (i = 0; i < 2; i++) {
+ ret = bf_vendor_write(chip, BF_REQ_KEEPALIVE, 0x0000, 0x3000);
+ if (ret < 0)
+ return ret;
+ }
+ for (i = 0; i < 3; i++) {
+ ret = bf_vendor_write(chip, BF_REQ_KEEPALIVE, 0x0800, 0x0800);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
+/* The 0x16 cold-init clear covers only 0x00-0x3D — the "cross"
+ * registers of a block (L-reg odd / R-reg even of the stereo
+ * sources) survive from the previous session and would sum L+R into
+ * BOTH channels of the output (mono). Zero them explicitly: 10 odd
+ * L-registers (5,7,…23) + 10 even R-registers (4,6,…22).
+ */
+int bf_crosspoint_clear_cross(struct snd_usb_babyface *chip,
+ unsigned int blk)
+{
+ int ret, k;
+ u16 flag;
+
+ for (k = 5; k < 24; k += 2) {
+ flag = bf_flag_cycle[chip->flag_cnt];
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0000,
+ (BF_REG_CROSS_BASE_L +
+ BF_REG_CROSS_STRIDE * blk + k) | flag);
+ if (ret < 0)
+ return ret;
+ }
+ for (k = 4; k < 24; k += 2) {
+ flag = bf_flag_cycle[chip->flag_cnt];
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0000,
+ (BF_REG_CROSS_BASE_R +
+ BF_REG_CROSS_STRIDE * blk + k) | flag);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
+/* ── mixer-state persistence across interface re-probes ────────
+ * A userspace client can claim the proprietary interface via usbfs
+ * (USBDEVFS_DISCONNECT_CLAIM — seen with PipeWire grabbing the
+ * device when a stream targets the sink, and with the TuxMix
+ * user-space daemon's libusb). That detaches us and the card
+ * disappears for the duration; on release the interface re-probes.
+ * The device keeps its registers across the detach, but our cold
+ * init clears them — so save the mixer state at disconnect and
+ * restore it at the next probe.
+ */
+
+static LIST_HEAD(bf_saved_list);
+static DEFINE_MUTEX(bf_saved_mutex);
+
+/* Re-apply the whole cached mixer state after a resume (the device
+ * lost its registers across a system suspend — TotalMix does the same
+ * re-apply). Caller holds chip->mutex.
+ */
+int babyface_restore_state(struct snd_usb_babyface *chip)
+{
+ int out, src, mic, ret;
+ u16 flag;
+
+ /* Preamp state + commit. */
+ ret = bf_preamp_state_write(chip);
+ if (ret < 0)
+ return ret;
+
+ /* The four mic gains (the counter restarts). */
+ for (mic = 0; mic < 4; mic++) {
+ u8 counter = (mic % 3 == 0) ? 0x20 : (mic % 3 == 1) ? 0x00 : 0x40;
+
+ ret = bf_vendor_write(chip, BF_REQ_GAIN,
+ (u16)((bf_gain_raw(mic, chip->gain[mic]) & 0x1f) |
+ counter),
+ BF_REG_GAIN + mic);
+ if (ret < 0)
+ return ret;
+ }
+ chip->gain_cycle = 1;
+
+ /* Masters (8-bit = the real volume) + mutes. */
+ ret = bf_apply_masters(chip);
+ if (ret < 0)
+ return ret;
+
+ /* Crosspoints (canonical out → register block). */
+ for (out = 0; out < 6; out++) {
+ unsigned int blk = bf_xpoint_block[out];
+
+ for (src = 0; src < 14; src++) {
+ flag = bf_flag_cycle[chip->flag_cnt];
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT,
+ chip->xpoint[out][src][0],
+ (BF_REG_CROSS_BASE_L +
+ BF_REG_CROSS_STRIDE * blk +
+ bf_sources[src].idx_l) | flag);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT,
+ chip->xpoint[out][src][1],
+ (BF_REG_CROSS_BASE_R +
+ BF_REG_CROSS_STRIDE * blk +
+ bf_sources[src].idx_r) | flag);
+ if (ret < 0)
+ return ret;
+ }
+ ret = bf_crosspoint_clear_cross(chip, blk);
+ if (ret < 0)
+ return ret;
+ }
+
+ /* Pitch (the DDS quad) + the clock keepalive. */
+ if (chip->pitch) {
+ u32 dds24 = (12800000000u + (u32)(1000 + chip->pitch) / 2) /
+ (u32)(1000 + chip->pitch);
+ u16 dds16 = dds24 >> 8;
+ u16 frac = dds24 & 0xff;
+
+ ret = bf_vendor_write(chip, BF_REQ_DDS, dds16, (frac << 8) | 0);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_DDS,
+ (u16)((dds16 * 72562ull + 50000) / 100000), 0x0001);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_DDS, (u16)((dds16 * 2 + 1) / 3),
+ 0x0002);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_DDS, 0x7cff, 0x0003);
+ if (ret < 0)
+ return ret;
+ }
+ return bf_vendor_write(chip, BF_REQ_KEEPALIVE, 0x0001,
+ BF_REG_KEEPALIVE_SETTINGS);
+}
+
+/* Re-apply the non-master flags (loopback / AN1>2 / link / width /
+ * FX send / MS) after a state restore. The write patterns mirror the
+ * corresponding _put() handlers. Caller holds chip->mutex.
+ */
+int bf_state_apply_flags(struct snd_usb_babyface *chip)
+{
+ int out, ret, on_out = -1;
+ u16 l, r;
+
+ /* Loopback: the full 30-channel map from the cached state (the
+ * single-active invariant keeps at most one pair at 0x0001).
+ */
+ for (out = 0; out < 6; out++) {
+ if (chip->loopback[out]) {
+ on_out = out;
+ break;
+ }
+ }
+ ret = bf_loopback_write_map(chip, on_out, on_out >= 0);
+ if (ret < 0)
+ return ret;
+
+ ret = bf_vendor_write(chip, BF_REQ_PREAMP,
+ (chip->linked ? 0x0400 : 0x0000) |
+ (chip->an12 ? 0x1000 : 0x0000), 0x1000);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_PREAMP_COMMIT, 0x0000, 0x0000);
+ if (ret < 0)
+ return ret;
+
+ l = (u16)(((0x2000 * (100 + chip->width) / 2) + 50) / 100);
+ r = 0x2000 - l;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, l, 0x0000);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, r, 0x001a);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, r, 0x0001);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, l, 0x001b);
+ if (ret < 0)
+ return ret;
+
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, chip->fx_send, 0x0138);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, chip->fx_send, 0x0153);
+ if (ret < 0)
+ return ret;
+
+ if (chip->ms_proc) {
+ /* Same ON pattern as bf_ms_put (cap_ms2.pcap): mute the AN2
+ * (side) crosspoints, both maps.
+ */
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0000, 0x0035);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0000, 0x004f);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0000, 0x0001);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0000, 0x001b);
+ if (ret < 0)
+ return ret;
+ }
+
+ /* Re-apply an engaged DIM (the fixed -20 dB Phones pair + flag). */
+ if (chip->dim) {
+ ret = bf_vendor_write(chip, BF_REQ_GAIN, 0xcb,
+ BF_REG_MASTER_8 + 2 * 1);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_GAIN, 0xcb,
+ BF_REG_MASTER_8 + 2 * 1 + 1);
+ if (ret < 0)
+ return ret;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0333,
+ (BF_REG_MASTER_16 + 2 * 1) |
+ bf_flag_cycle[chip->flag_cnt]);
+ if (ret < 0)
+ return ret;
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+ ret = bf_vendor_write(chip, BF_REQ_CROSSPOINT, 0x0333,
+ (BF_REG_MASTER_16 + 2 * 1 + 1) |
+ bf_flag_cycle[chip->flag_cnt]);
+ if (ret < 0)
+ return ret;
+ chip->flag_cnt = (chip->flag_cnt + 1) & 3;
+ ret = bf_vendor_write(chip, BF_REQ_PREAMP, 0x2000, 0x2000);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
+void bf_state_save(struct snd_usb_babyface *chip)
+{
+ struct bf_saved *s;
+ const char *key = chip->dev->serial ? chip->dev->serial :
+ dev_name(&chip->dev->dev);
+ bool found = false;
+
+ mutex_lock(&bf_saved_mutex);
+ list_for_each_entry(s, &bf_saved_list, list) {
+ if (strcmp(s->key, key))
+ continue;
+ found = true;
+ break;
+ }
+ if (!found) {
+ s = kzalloc_obj(*s, GFP_KERNEL);
+ if (!s) {
+ mutex_unlock(&bf_saved_mutex);
+ return;
+ }
+ strscpy(s->key, key, sizeof(s->key));
+ list_add_tail(&s->list, &bf_saved_list);
+ }
+
+ s->preamp = chip->preamp;
+ memcpy(s->gain, chip->gain, sizeof(s->gain));
+ s->gain_cycle = chip->gain_cycle;
+ s->flag_cnt = chip->flag_cnt;
+ memcpy(s->master, chip->master, sizeof(s->master));
+ memcpy(s->muted, chip->muted, sizeof(s->muted));
+ memcpy(s->xpoint, chip->xpoint, sizeof(s->xpoint));
+ s->pitch = chip->pitch;
+ memcpy(s->loopback, chip->loopback, sizeof(s->loopback));
+ s->an12 = chip->an12;
+ s->linked = chip->linked;
+ s->ms_proc = chip->ms_proc;
+ s->width = chip->width;
+ s->fx_send = chip->fx_send;
+ s->dim = chip->dim;
+ mutex_unlock(&bf_saved_mutex);
+}
+
+/* Copy a saved state (if any) into a freshly probed chip and push it
+ * to the device. Returns 1 when restored, -ENOENT when there is none,
+ * or a negative error from the vendor writes.
+ */
+int bf_state_restore(struct snd_usb_babyface *chip)
+{
+ struct bf_saved *s;
+ const char *key = chip->dev->serial ? chip->dev->serial :
+ dev_name(&chip->dev->dev);
+ int ret = -ENOENT;
+
+ mutex_lock(&bf_saved_mutex);
+ list_for_each_entry(s, &bf_saved_list, list) {
+ if (strcmp(s->key, key))
+ continue;
+ chip->preamp = s->preamp;
+ memcpy(chip->gain, s->gain, sizeof(chip->gain));
+ chip->gain_cycle = s->gain_cycle;
+ chip->flag_cnt = s->flag_cnt;
+ memcpy(chip->master, s->master, sizeof(chip->master));
+ memcpy(chip->muted, s->muted, sizeof(chip->muted));
+ memcpy(chip->xpoint, s->xpoint, sizeof(chip->xpoint));
+ chip->pitch = s->pitch;
+ memcpy(chip->loopback, s->loopback, sizeof(chip->loopback));
+ chip->an12 = s->an12;
+ chip->linked = s->linked;
+ chip->ms_proc = s->ms_proc;
+ chip->width = s->width;
+ chip->fx_send = s->fx_send;
+ chip->dim = s->dim;
+ ret = 1;
+ break;
+ }
+ mutex_unlock(&bf_saved_mutex);
+ if (ret != 1)
+ return ret;
+
+ mutex_lock(&chip->mutex);
+ ret = babyface_restore_state(chip);
+ if (ret == 0)
+ ret = bf_state_apply_flags(chip);
+ mutex_unlock(&chip->mutex);
+ return ret ? ret : 1;
+}
+
+void bf_state_purge(void)
+{
+ struct bf_saved *s, *tmp;
+
+ mutex_lock(&bf_saved_mutex);
+ list_for_each_entry_safe(s, tmp, &bf_saved_list, list) {
+ list_del(&s->list);
+ kfree(s);
+ }
+ mutex_unlock(&bf_saved_mutex);
+}
+
+/* ── stream (interrupt URBs, caiaq-style) ──────────────── */
+
+static bool babyface_capture_copy(struct snd_usb_babyface *chip,
+ struct snd_pcm_substream *subs,
+ const u8 *data, unsigned int frames)
+{
+ struct snd_pcm_runtime *rt = subs->runtime;
+ unsigned int buf_frames = rt->buffer_size;
+ unsigned int words = chip->frame_bytes / 4;
+ unsigned int chans = rt->channels;
+ unsigned int pos, f, i;
+ unsigned long new_period;
+ bool crossed = false;
+ u8 *dst;
+
+ spin_lock(&chip->lock);
+ pos = chip->hw_ptr[SNDRV_PCM_STREAM_CAPTURE] % buf_frames;
+ for (f = 0; f < frames; f++) {
+ const __le32 *w = (const __le32 *)(data + f * chip->frame_bytes);
+
+ dst = rt->dma_area + frames_to_bytes(rt, pos);
+ for (i = 0; i < chans; i++) {
+ /* Channel map: app ch0-3 = device words 0-3 (AN1-4);
+ * app ch4-9 = words 6-11 (ADAT/SPDIF); app ch10/11 =
+ * words 12/13 = a FIXED-GAIN playback tap (observed
+ * 2026-08-25: the playback echoes there at ~−27 dB,
+ * independent of the output masters — NOT the output
+ * bus; the ADAT/SPDIF range is words 6-11 only). The
+ * device words 4/5 are a fixed marker, not audio —
+ * skipped. At 96/192 kHz the frame has fewer words;
+ * missing ones read as zero.
+ */
+ static const u8 map[12] = { 0, 1, 2, 3, 6, 7, 8, 9,
+ 10, 11, 12, 13 };
+ u8 wi = i < 12 ? map[i] : 0xff;
+ s32 s = 0;
+
+ if (wi < words) {
+ /* 24-bit sample in bytes 1-3; arithmetic shift
+ * sign-extends from bit 23. S24_LE container.
+ */
+ s = (s32)le32_to_cpu(w[wi]) >> 8;
+ }
+ put_unaligned_le32((u32)s, dst + i * 4);
+ }
+ pos++;
+ if (pos >= buf_frames)
+ pos = 0;
+ }
+ chip->hw_ptr[SNDRV_PCM_STREAM_CAPTURE] += frames;
+ new_period = chip->hw_ptr[SNDRV_PCM_STREAM_CAPTURE] / rt->period_size;
+ if (new_period != chip->prev_period[SNDRV_PCM_STREAM_CAPTURE]) {
+ chip->prev_period[SNDRV_PCM_STREAM_CAPTURE] = new_period;
+ crossed = true;
+ }
+ spin_unlock(&chip->lock);
+
+ return crossed;
+}
+
+static bool babyface_playback_copy(struct snd_usb_babyface *chip,
+ struct snd_pcm_substream *subs,
+ u8 *data, unsigned int frames)
+{
+ struct snd_pcm_runtime *rt = subs->runtime;
+ unsigned int buf_frames = rt->buffer_size;
+ unsigned int words = chip->frame_bytes / 4;
+ unsigned int chans = rt->channels;
+ unsigned int pos, f, i;
+ unsigned long new_period;
+ bool crossed = false;
+ const u8 *src;
+
+ spin_lock(&chip->lock);
+ /* Clamp to what the app has actually written: the in-flight URBs
+ * (nurbs × frames_per_urb) can exceed the app ring, and without
+ * this the driver advances hw_ptr past appl_ptr — the ALSA core
+ * then flags a spurious XRUN on the next app interaction even
+ * though the app refills on schedule (seen at period 16-128 /
+ * 96-192 kHz with nurbs=16). The device just repeats the last
+ * frames (stale audio) instead of corrupting the stream state.
+ * NB: subtract the unbounded counters directly — modulo arithmetic
+ * is ambiguous at exact buffer multiples (appl=512, hw=0 → both
+ * wrap to 0).
+ */
+ {
+ snd_pcm_sframes_t data =
+ (snd_pcm_sframes_t)(rt->control->appl_ptr -
+ chip->hw_ptr[SNDRV_PCM_STREAM_PLAYBACK]);
+ if (data < 0)
+ data = 0;
+ if (data > (snd_pcm_sframes_t)buf_frames)
+ data = (snd_pcm_sframes_t)buf_frames;
+ if ((unsigned int)data < frames)
+ frames = (unsigned int)data;
+ }
+ pos = chip->hw_ptr[SNDRV_PCM_STREAM_PLAYBACK] % buf_frames;
+ for (f = 0; f < frames; f++) {
+ __le32 *w = (__le32 *)(data + f * chip->frame_bytes);
+
+ src = rt->dma_area + frames_to_bytes(rt, pos);
+ /* App ch n feeds the device word n (PB1-6 = words 0-11);
+ * words 12/13 stay zero. At 96/192 kHz the frame is
+ * shorter — the extra app channels are dropped.
+ */
+ for (i = 0; i < chans && i < words; i++) {
+ u32 s = get_unaligned_le32(src + i * 4);
+
+ /* 24-bit sample into bytes 1-3, byte 0 = 0. */
+ w[i] = cpu_to_le32((s & 0x00ffffff) << 8);
+ }
+ for (; i < words; i++)
+ w[i] = 0;
+ pos++;
+ if (pos >= buf_frames)
+ pos = 0;
+ }
+ chip->hw_ptr[SNDRV_PCM_STREAM_PLAYBACK] += frames;
+ new_period = chip->hw_ptr[SNDRV_PCM_STREAM_PLAYBACK] / rt->period_size;
+ if (new_period != chip->prev_period[SNDRV_PCM_STREAM_PLAYBACK]) {
+ chip->prev_period[SNDRV_PCM_STREAM_PLAYBACK] = new_period;
+ crossed = true;
+ }
+ spin_unlock(&chip->lock);
+
+ return crossed;
+}
+
+static void babyface_complete_in(struct urb *urb)
+{
+ struct snd_usb_babyface *chip = urb->context;
+ struct snd_pcm_substream *subs;
+ unsigned long flags;
+ unsigned int frames;
+ bool crossed = false;
+ int ret;
+
+ if (urb->status < 0) {
+ if (urb->status == -ESHUTDOWN || urb->status == -ENOENT ||
+ urb->status == -ECONNRESET)
+ return; /* killed */
+ dev_dbg_ratelimited(&chip->dev->dev, "IN urb status %d\n",
+ urb->status);
+ if (atomic_inc_return(&chip->urb_err) >= BF_URB_ERR_STOP)
+ schedule_work(&chip->stream_work);
+ goto resubmit;
+ }
+ atomic_set(&chip->urb_err, 0);
+
+ subs = READ_ONCE(chip->subs[SNDRV_PCM_STREAM_CAPTURE]);
+ if (subs) {
+ snd_pcm_stream_lock_irqsave(subs, flags);
+ if (snd_pcm_running(subs)) {
+ frames = urb->actual_length / chip->frame_bytes;
+ if (frames)
+ crossed = babyface_capture_copy(chip, subs,
+ urb->transfer_buffer,
+ frames);
+ }
+ snd_pcm_stream_unlock_irqrestore(subs, flags);
+ if (crossed)
+ snd_pcm_period_elapsed(subs);
+ }
+resubmit:
+ ret = usb_submit_urb(urb, GFP_ATOMIC);
+ if (ret < 0) {
+ dev_err_ratelimited(&chip->dev->dev,
+ "IN resubmit failed: %d\n", ret);
+ if (atomic_inc_return(&chip->urb_err) >= BF_URB_ERR_STOP)
+ schedule_work(&chip->stream_work);
+ }
+}
+
+static void babyface_complete_out(struct urb *urb)
+{
+ struct snd_usb_babyface *chip = urb->context;
+ struct snd_pcm_substream *subs;
+ unsigned long flags;
+ unsigned int frames;
+ bool crossed = false;
+ int ret;
+
+ if (urb->status < 0) {
+ if (urb->status == -ESHUTDOWN || urb->status == -ENOENT ||
+ urb->status == -ECONNRESET)
+ return; /* killed */
+ dev_dbg_ratelimited(&chip->dev->dev, "OUT urb status %d\n",
+ urb->status);
+ if (atomic_inc_return(&chip->urb_err) >= BF_URB_ERR_STOP)
+ schedule_work(&chip->stream_work);
+ goto resubmit;
+ }
+ atomic_set(&chip->urb_err, 0);
+
+ subs = READ_ONCE(chip->subs[SNDRV_PCM_STREAM_PLAYBACK]);
+ if (subs) {
+ snd_pcm_stream_lock_irqsave(subs, flags);
+ if (snd_pcm_running(subs)) {
+ frames = chip->frames_per_urb;
+ crossed = babyface_playback_copy(chip, subs,
+ urb->transfer_buffer, frames);
+ }
+ snd_pcm_stream_unlock_irqrestore(subs, flags);
+ if (crossed)
+ snd_pcm_period_elapsed(subs);
+ } else {
+ /* No consumer: silence the OUT frames. */
+ memset(urb->transfer_buffer, 0, urb->transfer_buffer_length);
+ }
+resubmit:
+ ret = usb_submit_urb(urb, GFP_ATOMIC);
+ if (ret < 0) {
+ dev_err_ratelimited(&chip->dev->dev,
+ "OUT resubmit failed: %d\n", ret);
+ if (atomic_inc_return(&chip->urb_err) >= BF_URB_ERR_STOP)
+ schedule_work(&chip->stream_work);
+ }
+}
+
+void babyface_stream_kill(struct snd_usb_babyface *chip)
+{
+ int i;
+
+ for (i = 0; i < chip->nurbs; i++) {
+ usb_kill_urb(chip->urbs_in[i]);
+ usb_kill_urb(chip->urbs_out[i]);
+ }
+ chip->streaming = false;
+}
+
+/* Stream start/stop run in process context (control transfers sleep).
+ * The trigger only toggles stream_users and schedules this work.
+ */
+
+/* Stop both PCM substreams (if running) so apps blocked in read/write
+ * wake with a clean error: XRUN for a recoverable stream error, or
+ * DISCONNECTED when the card is going away.
+ */
+void babyface_pcm_stop_both(struct snd_usb_babyface *chip, snd_pcm_state_t state)
+{
+ int s;
+
+ for (s = 0; s < 2; s++) {
+ struct snd_pcm_substream *subs = READ_ONCE(chip->subs[s]);
+
+ if (subs && snd_pcm_running(subs))
+ snd_pcm_stop(subs, state);
+ }
+}
+
+/* Re-count stream_users from the substream running states. The apps
+ * can recover (re-prepare + trigger) while the stream work runs, so a
+ * hard `= 0` would wipe a fresh increment and leave a RUNNING
+ * substream with no URBs (hang). Called on the error paths with the
+ * mutex held.
+ */
+static void bf_recount_users(struct snd_usb_babyface *chip)
+{
+ unsigned long flags;
+ int s, users = 0;
+
+ for (s = 0; s < 2; s++) {
+ struct snd_pcm_substream *subs = READ_ONCE(chip->subs[s]);
+
+ if (subs && snd_pcm_running(subs))
+ users++;
+ }
+ spin_lock_irqsave(&chip->lock, flags);
+ chip->stream_users = users;
+ spin_unlock_irqrestore(&chip->lock, flags);
+}
+
+void babyface_stream_work(struct work_struct *work)
+{
+ struct snd_usb_babyface *chip =
+ container_of(work, struct snd_usb_babyface, stream_work);
+ unsigned int urbsize = chip->frame_bytes * chip->frames_per_urb;
+ unsigned long flags;
+ int i, ret;
+ int users;
+
+ mutex_lock(&chip->mutex);
+
+ if (chip->shutdown) {
+ mutex_unlock(&chip->mutex);
+ return;
+ }
+
+ /* Persistent URB errors (bad link, device wedged): stop the stream
+ * and wake the apps with -EPIPE. stream_users is re-counted from
+ * the (now stopped) substreams so an app recovery (prepare+start)
+ * re-arms the session from a clean slate.
+ */
+ if (atomic_read(&chip->urb_err) >= BF_URB_ERR_STOP) {
+ dev_err(&chip->dev->dev,
+ "stream error: %d consecutive bad URBs, stopping (apps re-arm)\n",
+ BF_URB_ERR_STOP);
+ babyface_pcm_stop_both(chip, SNDRV_PCM_STATE_XRUN);
+ if (chip->streaming)
+ babyface_stream_kill(chip);
+ bf_recount_users(chip);
+ atomic_set(&chip->urb_err, 0);
+ mutex_unlock(&chip->mutex);
+ return;
+ }
+
+ spin_lock_irqsave(&chip->lock, flags);
+ users = chip->stream_users;
+ spin_unlock_irqrestore(&chip->lock, flags);
+
+ if (users > 0 && !chip->streaming) {
+ /* The firmware only validates a stream session that is
+ * preceded by the full cold-init (the user-space reference
+ * sends streaming_init at every session start — without it
+ * the outputs stay silent). The 0x16 clear wipes the mixer
+ * registers, so the cached state is re-applied after the arm.
+ */
+ ret = bf_cold_init(chip);
+ if (ret < 0)
+ goto err;
+
+ /* Stream trigger pair (cap_audio): 0x10 0x8000 + 0x1D. */
+ ret = bf_vendor_write(chip, BF_REQ_KEEPALIVE, 0x0000, 0x8000);
+ if (ret < 0)
+ goto err;
+ ret = bf_vendor_write(chip, BF_REQ_SESSION_START, 0x0000, 0x0000);
+ if (ret < 0)
+ goto err;
+
+ for (i = 0; i < chip->nurbs; i++) {
+ usb_fill_int_urb(chip->urbs_in[i], chip->dev,
+ usb_rcvintpipe(chip->dev, BF_EP_IN),
+ chip->buf_in[i], urbsize,
+ babyface_complete_in, chip, 1);
+ usb_fill_int_urb(chip->urbs_out[i], chip->dev,
+ usb_sndintpipe(chip->dev, BF_EP_OUT),
+ chip->buf_out[i], urbsize,
+ babyface_complete_out, chip, 1);
+ }
+ for (i = 0; i < chip->nurbs; i++) {
+ ret = usb_submit_urb(chip->urbs_in[i], GFP_KERNEL);
+ if (ret < 0)
+ goto err;
+ ret = usb_submit_urb(chip->urbs_out[i], GFP_KERNEL);
+ if (ret < 0)
+ goto err;
+ }
+ /* Session arm (cap_audio frame 5829, after the URBs). */
+ ret = bf_vendor_write(chip, BF_REQ_SESSION_ARM, 0x0000, 0xc000);
+ if (ret < 0)
+ goto err;
+
+ /* The cold init above cleared the mixer registers; push the
+ * cached state back (preamp, gains, masters, crosspoints,
+ * pitch) so the session starts at the user's levels.
+ */
+ ret = babyface_restore_state(chip);
+ if (ret < 0)
+ goto err;
+
+ /* The 0x16 clear also wipes the flag registers (loopback,
+ * AN1>2, stereo link, width, FX send, MS) — re-apply them.
+ */
+ ret = bf_state_apply_flags(chip);
+ if (ret < 0)
+ goto err;
+
+ chip->streaming = true;
+ dev_dbg(&chip->dev->dev, "stream started (%u frames/URB, %u URBs)\n",
+ chip->frames_per_urb, chip->nurbs);
+ } else if (users == 0 && chip->streaming) {
+ babyface_stream_kill(chip);
+ dev_dbg(&chip->dev->dev, "stream stopped\n");
+ }
+
+ mutex_unlock(&chip->mutex);
+ return;
+
+err:
+ dev_err(&chip->dev->dev, "failed to start stream: %d\n", ret);
+ babyface_stream_kill(chip);
+ /* The apps already got a successful trigger — wake them with an
+ * XRUN so a failed start (device wedged, cold-init error) does not
+ * leave them hung in read/write with no URBs in flight.
+ */
+ babyface_pcm_stop_both(chip, SNDRV_PCM_STATE_XRUN);
+ bf_recount_users(chip);
+ mutex_unlock(&chip->mutex);
+}
+
+/* ── PCM ─────────────────────────── */
+
+static const struct snd_pcm_hardware babyface_pcm_hw = {
+ .info = SNDRV_PCM_INFO_INTERLEAVED |
+ SNDRV_PCM_INFO_BLOCK_TRANSFER,
+ .formats = SNDRV_PCM_FMTBIT_S24_LE,
+ .rate_min = 32000,
+ .rate_max = 192000,
+ .channels_min = 2,
+ .channels_max = 12,
+ .buffer_bytes_max = 1 << 20,
+ .period_bytes_max = 1 << 18,
+ .periods_min = 2,
+ .periods_max = 16,
+};
+
+static int babyface_pcm_open(struct snd_pcm_substream *subs)
+{
+ struct snd_usb_babyface *chip = snd_pcm_substream_chip(subs);
+ struct snd_pcm_runtime *rt = subs->runtime;
+ unsigned long flags;
+ int ret;
+
+ rt->hw = babyface_pcm_hw;
+ ret = snd_pcm_hw_constraint_list(rt, 0, SNDRV_PCM_HW_PARAM_RATE,
+ &bf_rates_constraint);
+ if (ret < 0)
+ return ret;
+ /* One URB delivers frames_per_urb frames per interrupt; a period must
+ * span at least one URB so a completion crosses at most one period
+ * boundary. Constrain in frames (not bytes) so the minimum period
+ * does not balloon at low channel counts: 2 ch @ 48 kHz → 256
+ * frames (5.3 ms) instead of 1536 frames from a 12-ch byte clamp.
+ */
+ ret = snd_pcm_hw_constraint_minmax(rt, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
+ chip->frames_per_urb, 1 << 18);
+ if (ret < 0)
+ return ret;
+
+ spin_lock_irqsave(&chip->lock, flags);
+ chip->subs[subs->stream] = subs;
+ spin_unlock_irqrestore(&chip->lock, flags);
+ return 0;
+}
+
+static int babyface_pcm_close(struct snd_pcm_substream *subs)
+{
+ struct snd_usb_babyface *chip = snd_pcm_substream_chip(subs);
+ unsigned long flags;
+
+ /* Wait for the stream stop work so the URB callbacks (which
+ * touch subs) are done before the substream can be freed.
+ */
+ flush_work(&chip->stream_work);
+ spin_lock_irqsave(&chip->lock, flags);
+ chip->subs[subs->stream] = NULL;
+ spin_unlock_irqrestore(&chip->lock, flags);
+ return 0;
+}
+
+static int babyface_pcm_hw_params(struct snd_pcm_substream *subs,
+ struct snd_pcm_hw_params *params)
+{
+ struct snd_usb_babyface *chip = snd_pcm_substream_chip(subs);
+ const struct bf_rate *r;
+ int ret = 0;
+
+ r = bf_rate_lookup(params_rate(params));
+ if (!r)
+ return -EINVAL;
+
+ /* The stream URBs must be at least one alt packet wide: the device
+ * delivers its IN data in alt-sized packets (448/640/1024 B for
+ * alt 1/2/3), and a smaller URB buffer makes the host controller
+ * discard the transfer with -EOVERFLOW (babble) — seen at
+ * 176.4/192 kHz with frames_per_urb below 32. Return a clean
+ * error instead of a silently dead capture stream.
+ */
+ if (chip->frames_per_urb < r->min_fpu) {
+ dev_err(&chip->dev->dev,
+ "rate %u Hz needs frames_per_urb >= %u (module has %u)\n",
+ r->rate, r->min_fpu, chip->frames_per_urb);
+ return -EINVAL;
+ }
+
+ mutex_lock(&chip->mutex);
+ if (r->rate != chip->rate) {
+ /* Both directions share one clock, so a rate change must not
+ * race live transfers. Stop the URBs, re-point the bandwidth
+ * class and let the stream work restart the session at the
+ * new rate — the other running substream briefly sees a rate
+ * step (PipeWire re-negotiates via its resampler) instead of
+ * this open failing with -EBUSY (which killed the PW sink).
+ */
+ if (chip->streaming) {
+ unsigned long flags;
+
+ babyface_stream_kill(chip);
+ spin_lock_irqsave(&chip->lock, flags);
+ if (chip->stream_users > 0)
+ schedule_work(&chip->stream_work);
+ spin_unlock_irqrestore(&chip->lock, flags);
+ }
+ ret = usb_set_interface(chip->dev, BF_IFACE, r->alt);
+ if (ret < 0)
+ goto out;
+ chip->rate = r->rate;
+ chip->alt = r->alt;
+ chip->frame_bytes = r->frame_bytes;
+ /* The DSP EQ coefficients depend on fs: re-upload. */
+ bf_eq_reupload(chip);
+ dev_dbg(&chip->dev->dev, "rate %u Hz (alt %u)\n",
+ chip->rate, chip->alt);
+ }
+out:
+ mutex_unlock(&chip->mutex);
+ return ret;
+}
+
+static int babyface_pcm_hw_free(struct snd_pcm_substream *subs)
+{
+ /* The device buffer is host-side; nothing to release here. */
+ return 0;
+}
+
+static int babyface_pcm_prepare(struct snd_pcm_substream *subs)
+{
+ struct snd_usb_babyface *chip = snd_pcm_substream_chip(subs);
+ unsigned long flags;
+
+ spin_lock_irqsave(&chip->lock, flags);
+ chip->hw_ptr[subs->stream] = 0;
+ chip->prev_period[subs->stream] = 0;
+ spin_unlock_irqrestore(&chip->lock, flags);
+ return 0;
+}
+
+static int babyface_pcm_trigger(struct snd_pcm_substream *subs, int cmd)
+{
+ struct snd_usb_babyface *chip = snd_pcm_substream_chip(subs);
+ unsigned long flags;
+
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ spin_lock_irqsave(&chip->lock, flags);
+ chip->hw_ptr[subs->stream] = 0;
+ chip->prev_period[subs->stream] = 0;
+ /* stream_users is shared by the two substreams (separate
+ * locks) — serialize the ++/-- so a concurrent trigger on
+ * the other direction can't lose an increment (which would
+ * stop the stream while a substream still runs).
+ */
+ if (chip->stream_users++ == 0)
+ schedule_work(&chip->stream_work);
+ spin_unlock_irqrestore(&chip->lock, flags);
+ return 0;
+ case SNDRV_PCM_TRIGGER_STOP:
+ spin_lock_irqsave(&chip->lock, flags);
+ if (chip->stream_users > 0 && --chip->stream_users == 0)
+ schedule_work(&chip->stream_work);
+ spin_unlock_irqrestore(&chip->lock, flags);
+ return 0;
+ }
+ return -EINVAL;
+}
+
+static snd_pcm_uframes_t babyface_pcm_pointer(struct snd_pcm_substream *subs)
+{
+ struct snd_usb_babyface *chip = snd_pcm_substream_chip(subs);
+ unsigned long flags;
+ snd_pcm_uframes_t pos;
+
+ spin_lock_irqsave(&chip->lock, flags);
+ pos = chip->hw_ptr[subs->stream] % subs->runtime->buffer_size;
+ spin_unlock_irqrestore(&chip->lock, flags);
+ return pos;
+}
+
+static const struct snd_pcm_ops babyface_pcm_ops = {
+ .open = babyface_pcm_open,
+ .close = babyface_pcm_close,
+ .ioctl = snd_pcm_lib_ioctl,
+ .hw_params = babyface_pcm_hw_params,
+ .hw_free = babyface_pcm_hw_free,
+ .prepare = babyface_pcm_prepare,
+ .trigger = babyface_pcm_trigger,
+ .pointer = babyface_pcm_pointer,
+};
+
+static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
+static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;
+static int frames_per_urb = BF_FRAMES_PER_URB_DEFAULT;
+static int nurbs = BF_NURBS_DEFAULT;
+static int panel_poll_ms = BF_PANEL_POLL_MS_DEFAULT;
+
+module_param_array(index, int, NULL, 0444);
+MODULE_PARM_DESC(index, "Index value for the Babyface Pro FS sound card.");
+module_param_array(id, charp, NULL, 0444);
+MODULE_PARM_DESC(id, "ID string for the Babyface Pro FS sound card.");
+module_param(frames_per_urb, int, 0644);
+MODULE_PARM_DESC(frames_per_urb, "Audio frames per URB, 8..1024 (16 = low-latency floor, 256 = default).");
+module_param(nurbs, int, 0644);
+MODULE_PARM_DESC(nurbs, "URBs in flight per direction, 1..16 (16 = low-latency).");
+module_param(panel_poll_ms, int, 0644);
+MODULE_PARM_DESC(panel_poll_ms, "Front-panel poll interval in ms, 10..1000 (20 = default, matches Windows' ~50 Hz).");
+
+/* ── USB driver ───────────────────────── */
+
+static void babyface_private_free(struct snd_card *card)
+{
+ struct snd_usb_babyface *chip = card->private_data;
+ unsigned int urbsize;
+ int i;
+
+ if (!chip)
+ return;
+
+ /* The URB arrays are NULL when the probe failed before allocating
+ * them (snd_card_free runs private_free on any probe error).
+ */
+ if (chip->urbs_in) {
+ urbsize = chip->frame_bytes * chip->frames_per_urb;
+ for (i = 0; i < chip->nurbs; i++) {
+ if (chip->urbs_in[i]) {
+ usb_kill_urb(chip->urbs_in[i]);
+ usb_free_urb(chip->urbs_in[i]);
+ }
+ if (chip->urbs_out[i]) {
+ usb_kill_urb(chip->urbs_out[i]);
+ usb_free_urb(chip->urbs_out[i]);
+ }
+ usb_free_coherent(chip->dev, urbsize, chip->buf_in[i],
+ chip->dma_in[i]);
+ usb_free_coherent(chip->dev, urbsize, chip->buf_out[i],
+ chip->dma_out[i]);
+ }
+ }
+ kfree(chip->urbs_in);
+ kfree(chip->urbs_out);
+ kfree(chip->buf_in);
+ kfree(chip->buf_out);
+ kfree(chip->dma_in);
+ kfree(chip->dma_out);
+ usb_put_dev(chip->dev);
+}
+
+static int babyface_probe(struct usb_interface *intf,
+ const struct usb_device_id *usb_id)
+{
+ struct usb_device *dev = interface_to_usbdev(intf);
+ struct snd_usb_babyface *chip;
+ struct snd_card *card;
+ struct snd_pcm *pcm;
+ unsigned int urbsize;
+ u8 st[4];
+ int i, err;
+
+ if (intf->cur_altsetting->desc.bInterfaceNumber != BF_IFACE) {
+ /* Only the proprietary audio interface is ours; the MIDI
+ * (standard class) and bulk interfaces stay unclaimed so
+ * snd-usb-audio can take the MIDI one.
+ */
+ return -ENODEV;
+ }
+
+ frames_per_urb = clamp(frames_per_urb, 8, 1024) & ~7;
+ nurbs = clamp(nurbs, 1, 16);
+ panel_poll_ms = clamp(panel_poll_ms, 10, 1000);
+
+ err = snd_card_new(&intf->dev, index[0], id[0], THIS_MODULE,
+ sizeof(*chip), &card);
+ if (err < 0) {
+ dev_err(&intf->dev, "snd_card_new failed: %d\n", err);
+ return err;
+ }
+ chip = card->private_data;
+ chip->card = card;
+
+ chip->dev = usb_get_dev(dev);
+ /* USB autosuspend is untested: babyface_suspend()/_resume() don't
+ * check PMSG_IS_AUTO, and nothing in this driver holds a PM
+ * reference while streaming or while the panel poll/keepalive
+ * timers are running, so an autosuspend request could race a
+ * live stream or panel tick. Disable it explicitly rather than
+ * ship an untested code path — full autosuspend support (correct
+ * autopm_get/put pairing around the stream and the panel/keepalive
+ * work) is a deliberate follow-up, not an oversight.
+ */
+ usb_disable_autosuspend(chip->dev);
+ chip->iface = intf;
+ chip->nurbs = nurbs;
+ chip->frames_per_urb = frames_per_urb;
+ chip->panel_poll_ms = panel_poll_ms;
+ chip->rate = 48000;
+ chip->alt = BF_ALT_1;
+ chip->frame_bytes = 56;
+ chip->preamp = BF_PREAMP_BASE;
+ mutex_init(&chip->mutex);
+ spin_lock_init(&chip->lock);
+ atomic_set(&chip->urb_err, 0);
+ INIT_WORK(&chip->stream_work, babyface_stream_work);
+ INIT_DELAYED_WORK(&chip->panel_work, babyface_panel_work);
+ chip->card->private_free = babyface_private_free;
+
+ strscpy(chip->card->driver, "BabyfaceProFS",
+ sizeof(chip->card->driver));
+ strscpy(chip->card->shortname, "Babyface Pro FS",
+ sizeof(chip->card->shortname));
+ snprintf(chip->card->longname, sizeof(chip->card->longname),
+ "RME Babyface Pro FS (proprietary mode) at %s",
+ dev_name(&dev->dev));
+ strscpy(chip->card->mixername, "Babyface Pro FS",
+ sizeof(chip->card->mixername));
+
+ /* alt 1 = the default 48-kHz bandwidth class. */
+ err = usb_set_interface(dev, BF_IFACE, BF_ALT_1);
+ if (err < 0) {
+ dev_err(&intf->dev, "usb_set_interface failed: %d\n", err);
+ goto error;
+ }
+
+ err = bf_cold_init(chip);
+ if (err < 0) {
+ dev_err(&intf->dev, "cold init failed: %d\n", err);
+ goto error;
+ }
+
+ /* Sync the preamp state from the 0x17 readback (byte 0 mirrors
+ * the 48V/PAD bits; it persists across power cycles).
+ */
+ err = bf_vendor_read(chip, BF_REQ_PREAMP, BF_REG_PREAMP, st);
+ if (err < 0)
+ dev_dbg(&intf->dev, "preamp readback failed: %d\n", err);
+ else
+ chip->preamp = st[0];
+
+ /* Restore the mixer state saved at the last disconnect (if any);
+ * the device keeps its registers across a usbfs detach, but the
+ * cold init above cleared them, so push the user's settings back.
+ */
+ err = bf_state_restore(chip);
+ if (err == -ENOENT) {
+ /* No saved state: the 0x16 clear zeroed the mixer registers,
+ * so restore the factory default routing to keep the outputs
+ * live out of the box.
+ */
+ err = babyface_write_default_mixer(chip);
+ if (err < 0) {
+ dev_err(&intf->dev, "default mixer restore failed: %d\n", err);
+ goto error;
+ }
+ } else if (err < 0) {
+ dev_err(&intf->dev, "mixer state restore failed: %d\n", err);
+ goto error;
+ }
+
+ urbsize = chip->frame_bytes * chip->frames_per_urb;
+ chip->urbs_in = kcalloc(chip->nurbs, sizeof(*chip->urbs_in), GFP_KERNEL);
+ chip->urbs_out = kcalloc(chip->nurbs, sizeof(*chip->urbs_out), GFP_KERNEL);
+ chip->buf_in = kcalloc(chip->nurbs, sizeof(*chip->buf_in), GFP_KERNEL);
+ chip->buf_out = kcalloc(chip->nurbs, sizeof(*chip->buf_out), GFP_KERNEL);
+ chip->dma_in = kcalloc(chip->nurbs, sizeof(*chip->dma_in), GFP_KERNEL);
+ chip->dma_out = kcalloc(chip->nurbs, sizeof(*chip->dma_out), GFP_KERNEL);
+ if (!chip->urbs_in || !chip->urbs_out || !chip->buf_in ||
+ !chip->buf_out || !chip->dma_in || !chip->dma_out)
+ goto error;
+
+ for (i = 0; i < chip->nurbs; i++) {
+ chip->urbs_in[i] = usb_alloc_urb(0, GFP_KERNEL);
+ chip->urbs_out[i] = usb_alloc_urb(0, GFP_KERNEL);
+ chip->buf_in[i] = usb_alloc_coherent(dev, urbsize, GFP_KERNEL,
+ &chip->dma_in[i]);
+ chip->buf_out[i] = usb_alloc_coherent(dev, urbsize, GFP_KERNEL,
+ &chip->dma_out[i]);
+ if (!chip->urbs_in[i] || !chip->urbs_out[i] ||
+ !chip->buf_in[i] || !chip->buf_out[i])
+ goto error;
+ }
+
+ err = snd_pcm_new(chip->card, "Babyface Pro FS", 0, 1, 1, &pcm);
+ if (err < 0) {
+ dev_err(&intf->dev, "snd_pcm_new failed: %d\n", err);
+ goto error;
+ }
+ pcm->private_data = chip;
+ strscpy(pcm->name, "Babyface Pro FS", sizeof(pcm->name));
+ snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &babyface_pcm_ops);
+ snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &babyface_pcm_ops);
+
+ /* The PCM buffer is host-side (the URB callbacks copy in/out of
+ * it); vmalloc is the standard choice for that.
+ */
+ err = snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_VMALLOC,
+ NULL, 0, 1 << 20);
+ if (err < 0) {
+ dev_err(&intf->dev, "buffer allocation failed: %d\n", err);
+ goto error;
+ }
+
+ err = babyface_create_controls(chip);
+ if (err < 0) {
+ dev_err(&intf->dev, "control creation failed: %d\n", err);
+ goto error;
+ }
+
+ err = babyface_create_xpoints(chip);
+ if (err < 0) {
+ dev_err(&intf->dev, "crosspoint creation failed: %d\n", err);
+ goto error;
+ }
+
+ err = babyface_create_flags(chip);
+ if (err < 0) {
+ dev_err(&intf->dev, "flag control creation failed: %d\n", err);
+ goto error;
+ }
+
+ err = babyface_create_panel(chip);
+ if (err < 0) {
+ dev_err(&intf->dev, "front-panel control creation failed: %d\n", err);
+ goto error;
+ }
+
+ err = babyface_create_eq(chip);
+ if (err < 0) {
+ dev_err(&intf->dev, "EQ control creation failed: %d\n", err);
+ goto error;
+ }
+
+ /* The DSP coefficient stream (EQ, bulk ep 0x0A) lives on interface
+ * 1, which has a single altsetting (alt 0) already active in the
+ * default configuration — the endpoint is scheduled, no
+ * SET_INTERFACE or interface claim is needed (the earlier
+ * -EAGAIN was the on-stack transfer buffer, and SET_INTERFACE on
+ * interface 1 wedged the iface-5 audio stream — playback URBs
+ * never completed).
+ */
+
+ err = snd_card_register(chip->card);
+ if (err < 0) {
+ dev_err(&intf->dev, "snd_card_register failed: %d\n", err);
+ goto error;
+ }
+
+ /* The panel poll mirrors the physical buttons/wheel into the
+ * Front Panel controls; it runs for the whole card lifetime.
+ */
+ babyface_panel_start(chip);
+
+ usb_set_intfdata(intf, chip);
+ dev_info(&intf->dev,
+ "Babyface Pro FS: card %i, %u frames/URB, %u URBs/direction\n",
+ chip->card->number, chip->frames_per_urb, chip->nurbs);
+ return 0;
+
+error:
+ usb_set_intfdata(intf, NULL);
+ snd_card_free(chip->card);
+ return err;
+}
+
+static void babyface_disconnect(struct usb_interface *intf)
+{
+ struct snd_usb_babyface *chip = usb_get_intfdata(intf);
+
+ if (!chip)
+ return;
+
+ /* Idempotence guard: a disconnect can race a re-probe (usbfs
+ * detach/re-attach) — tear the card down exactly once.
+ */
+ usb_set_intfdata(intf, NULL);
+ if (chip->shutdown)
+ return;
+
+ /* Keep the mixer state for the next probe: a userspace usbfs
+ * claim (PipeWire sink grab, TuxMix daemon) detaches us and the
+ * cold init of the re-probe would otherwise wipe the settings.
+ */
+ bf_state_save(chip);
+
+ chip->shutdown = true;
+ cancel_work_sync(&chip->stream_work);
+ babyface_panel_stop(chip);
+ /* Balance the probe()-time usb_disable_autosuspend(): the usb_device
+ * outlives this interface claim (a usbfs detach re-probes without
+ * the physical device ever disconnecting), so leaving autosuspend
+ * disabled here would wrongly affect whatever claims the device next.
+ */
+ usb_enable_autosuspend(chip->dev);
+ /* Wake apps blocked in read/write: the card is going away. */
+ dev_info(&chip->dev->dev, "disconnect: stopping PCM substreams\n");
+ babyface_pcm_stop_both(chip, SNDRV_PCM_STATE_DISCONNECTED);
+ mutex_lock(&chip->mutex);
+ if (chip->streaming)
+ babyface_stream_kill(chip);
+ mutex_unlock(&chip->mutex);
+
+ snd_card_disconnect(chip->card);
+ /* NEVER snd_card_free() here: it blocks until the last user
+ * closes the card, and an open client (e.g. PipeWire) deadlocks
+ * the disconnect (seen live: pipewire stuck in snd_card_free,
+ * D state). free_when_closed frees on the last close.
+ */
+ snd_card_free_when_closed(chip->card);
+}
+
+static int babyface_suspend(struct usb_interface *intf, pm_message_t message)
+{
+ struct snd_usb_babyface *chip = usb_get_intfdata(intf);
+
+ struct snd_device *sdev;
+
+ if (!chip)
+ return 0;
+ list_for_each_entry(sdev, &chip->card->devices, list) {
+ if (sdev->type == SNDRV_DEV_PCM)
+ snd_pcm_suspend_all(sdev->device_data);
+ }
+ cancel_work_sync(&chip->stream_work);
+ babyface_panel_stop(chip);
+ mutex_lock(&chip->mutex);
+ if (chip->streaming)
+ babyface_stream_kill(chip);
+ mutex_unlock(&chip->mutex);
+ return 0;
+}
+
+static int babyface_resume(struct usb_interface *intf)
+{
+ struct snd_usb_babyface *chip = usb_get_intfdata(intf);
+ int err;
+
+ if (!chip)
+ return 0;
+
+ /* The device lost its state across the suspend; re-run the cold
+ * init and re-apply the cached mixer state. Suspended PCM
+ * substreams are woken by the core — apps get -ESTRPIPE and
+ * restart (the trigger re-arms the stream).
+ */
+ mutex_lock(&chip->mutex);
+ err = usb_set_interface(chip->dev, BF_IFACE, chip->alt);
+ if (err < 0)
+ goto out;
+ err = bf_cold_init(chip);
+ if (err < 0)
+ goto out;
+ err = babyface_restore_state(chip);
+out:
+ mutex_unlock(&chip->mutex);
+ if (!err)
+ babyface_panel_start(chip);
+ return err;
+}
+
+static const struct usb_device_id babyface_ids[] = {
+ { USB_DEVICE(USB_VENDOR_RME, USB_PRODUCT_BABYFACE_PRO_FS) },
+ { }
+};
+MODULE_DEVICE_TABLE(usb, babyface_ids);
+
+static struct usb_driver babyface_driver = {
+ .name = "snd-usb-babyface-pro",
+ .probe = babyface_probe,
+ .disconnect = babyface_disconnect,
+ .suspend = babyface_suspend,
+ .resume = babyface_resume,
+ .id_table = babyface_ids,
+};
+
+static int __init babyface_init(void)
+{
+ return usb_register(&babyface_driver);
+}
+
+static void __exit babyface_exit(void)
+{
+ bf_state_purge();
+ usb_deregister(&babyface_driver);
+}
+
+module_init(babyface_init);
+module_exit(babyface_exit);
+
+MODULE_AUTHOR("Ismaïl Bahloul <i.bahloul01@gmail.com>");
+MODULE_DESCRIPTION("RME Babyface Pro FS (proprietary mode) USB audio driver");
+MODULE_LICENSE("GPL");
diff --git a/sound/usb/babyfacepro/babyfacepro.h b/sound/usb/babyfacepro/babyfacepro.h
new file mode 100644
index 000000000..df90f48ed
--- /dev/null
+++ b/sound/usb/babyfacepro/babyfacepro.h
@@ -0,0 +1,391 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * RME Babyface Pro FS — proprietary-mode USB audio driver
+ *
+ * The Babyface Pro FS presents two personalities on the USB bus: a
+ * class-compliant one (handled by snd-usb-audio) and a proprietary one
+ * (VID 0x2a39 / PID 0x3fc0) whose PCM stream runs on INTERRUPT
+ * endpoints (interface 5, ep 0x01 OUT / 0x82 IN). Isochronous
+ * transfers are rejected there with EINVAL, and snd-usb-audio has no
+ * interrupt-PCM path, so this driver is standalone (snd-usb-caiaq-style
+ * interrupt streaming) instead of an snd-usb-audio quirk.
+ *
+ * The protocol (vendor requests + 14×32-bit frame layout) was
+ * reverse-engineered from Windows captures and validated on hardware —
+ * tools/usbdump/PROTOCOL.md is the authoritative reference.
+ *
+ * Stream notes (hardware-validated 2026-08):
+ * - frames_per_urb is tunable 8..1024 (multiple of 8) but must be at
+ * least one alt packet wide — the device delivers IN data in
+ * alt-sized packets (448/640/1024 B for alt 1/2/3), smaller URBs
+ * get -EOVERFLOW (babble). So frames_per_urb >= 8/16/32 for
+ * alt 1/2/3; the driver rejects violating rates in hw_params.
+ * - Validated sweep 256→128→64→32→16 (≤ 128 kHz): with nurbs=8 the
+ * period floor is 32 frames (0.67 ms @ 48 kHz) without glitches;
+ * nurbs=16 drops it to 16 frames (0.33 ms). Soaks (5-15 min,
+ * 2026-08-25) refine this: period 32 is the zero-glitch floor
+ * (0 xruns both directions); period 16 is rock-solid on playback
+ * but the capture side drops ~1 buffer per 7 s (0.67 ms each —
+ * any scheduler hiccup overruns a 0.33 ms ring) — fine for
+ * monitoring, not for clean recording. Defaults (256×8) match
+ * the RME TotalMix 256-sample buffer; the low-latency profile is
+ * 16×16.
+ * - The device only advances the stream while BOTH endpoints have a
+ * pending URB — IN and OUT are always submitted as a pair.
+ * - Sample rate = SET_INTERFACE(5, alt) only; the alt is a bandwidth
+ * class (alt 1 = 32/44.1/48/64/88.2 kHz, alt 2 = 96/128 kHz,
+ * alt 3 = 176.4/192 kHz), not a 1:1 rate code.
+ */
+
+#include <linux/log2.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/unaligned.h>
+#include <linux/usb.h>
+#include <linux/workqueue.h>
+#include <sound/control.h>
+#include <sound/tlv.h>
+#include <sound/core.h>
+#include <sound/initval.h>
+#include <sound/pcm.h>
+
+#define USB_VENDOR_RME 0x2a39
+#define USB_PRODUCT_BABYFACE_PRO_FS 0x3fc0
+
+/* The proprietary audio interface (interface 5, interrupt endpoints). */
+#define BF_IFACE 5
+#define BF_EP_OUT 0x01
+#define BF_EP_IN 0x82
+
+#define BF_ALT_1 1 /* 32/44.1/48/64/88.2 kHz, 448-B packets */
+#define BF_ALT_2 2 /* 96/128 kHz, 640-B packets */
+#define BF_ALT_3 3 /* 176.4/192 kHz, 1024-B packets */
+
+/* Default stream geometry — conservative, matches the RME TotalMix
+ * 256-sample buffer. Both are tunable via module params; the
+ * low-latency profile (validated) is frames_per_urb=16 nurbs=16.
+ */
+#define BF_FRAMES_PER_URB_DEFAULT 256
+#define BF_NURBS_DEFAULT 8
+
+/* Front-panel poll interval default — Windows polls the 5-register
+ * status set at ~50 cycles/s (20 ms); match that. Tunable via the
+ * panel_poll_ms module param for reviewers/distros who want a slower
+ * (or faster) rate than the Windows-matching default.
+ */
+#define BF_PANEL_POLL_MS_DEFAULT 20
+
+#define BF_WORDS_PER_FRAME 14 /* 14 × 32-bit words per frame */
+
+/* Consecutive URB errors (CRC/babble/protocol or a failed resubmit)
+ * before the stream is stopped and the apps get a clean -EPIPE.
+ */
+#define BF_URB_ERR_STOP 3
+
+/* Vendor requests (bmRequestType 0x40, value in wValue, no data phase). */
+#define BF_REQ_KEEPALIVE 0x10 /* settings word / stream trigger */
+#define BF_REQ_STATUS 0x11 /* read 4 B */
+#define BF_REQ_CROSSPOINT 0x12 /* 16-bit crosspoint / master */
+#define BF_REQ_SESSION_STOP 0x13 /* disarm — never sent mid-run */
+#define BF_REQ_SESSION_ARM 0x14
+#define BF_REQ_REG_CLEAR 0x16 /* cold-init register clear */
+#define BF_REQ_PREAMP 0x17 /* 48V/PAD state + readback */
+#define BF_REQ_GAIN 0x1a /* 8-bit gain / master companion */
+#define BF_REQ_DDS 0x1b /* clock quads */
+#define BF_REQ_STATUS_2 0x1c /* read 4 B */
+#define BF_REQ_SESSION_START 0x1d
+#define BF_REQ_PREAMP_COMMIT 0x21 /* commit after 0x17 */
+#define BF_REQ_LOOPBACK 0x15 /* per-output-channel flag */
+
+/* Loopback map width (captured 2026-08-25, cap_loopback2.pcap):
+ * TotalMix writes the FULL 30-channel 0x15 map on every toggle (ON =
+ * the pair at 0x0001 + the other 28 at 0x0000; OFF = all 0x0000).
+ * wIdx = 2×out_index: AN1/2 = 0/1, PH3/4 = 2/3, AS1/2 = 4/5, …
+ */
+#define BF_LOOPBACK_CHANNELS 30
+
+/* Register addresses. */
+#define BF_REG_PREAMP 0x003f
+#define BF_REG_MASTER_16 0x03e0 /* + 2·out (bReq 0x12) */
+#define BF_REG_MASTER_8 0x0004 /* + 2·out (bReq 0x1a) */
+#define BF_REG_GAIN 0x0000 /* + mic 0-3 (bReq 0x1a) */
+#define BF_REG_CROSS_BASE_L 0x0034 /* + 0x34·out + src (bReq 0x12) */
+#define BF_REG_CROSS_BASE_R 0x004e /* + 0x34·out + src */
+#define BF_REG_CROSS_STRIDE 0x0034
+#define BF_REG_KEEPALIVE_SETTINGS 0x05cf
+#define BF_REG_KEEPALIVE_INIT 0x05ff
+
+/* Front-panel readback (babyfacepro-ctl.c): 0x17 read at wIdx 0x0000 — the index
+ * the Windows driver polls (cap_buttons2.pcap). byte0 = preamp 48V/PAD,
+ * byte1 = OUT sel + DIM/MIX bits, byte2 = IN sel + wheel counter,
+ * byte3 = button flash (see babyfacepro-ctl.c for the full layout).
+ */
+#define BF_REG_PANEL_READ 0x0000
+#define BF_PANEL_IN_SHIFT 4
+#define BF_PANEL_IN_CH12 0x04
+#define BF_PANEL_IN_CH34 0x05
+#define BF_PANEL_IN_OPT 0x06
+/* OUT selection — the gain-display-mode encoding (cap_dim.pcap);
+ * babyfacepro-ctl.c also accepts the base-mode 0x01/0x02 (cap_buttons.pcap).
+ */
+#define BF_PANEL_OUT_CH12 0x04
+#define BF_PANEL_OUT_PHONES 0x05
+#define BF_PANEL_OUT_OPT 0x06
+#define BF_PANEL_FLASH_IN 0x41
+#define BF_PANEL_FLASH_SET 0x42
+#define BF_PANEL_FLASH_MIX 0x44
+#define BF_PANEL_FLASH_OUT 0x48
+#define BF_PANEL_FLASH_SELECT 0x50
+#define BF_PANEL_FLASH_DIM 0x60
+#define BF_PANEL_BTN_NONE 0
+#define BF_PANEL_BTN_IN 1
+#define BF_PANEL_BTN_SET 2
+#define BF_PANEL_BTN_MIX 3
+#define BF_PANEL_BTN_OUT 4
+#define BF_PANEL_BTN_SELECT 5
+#define BF_PANEL_BTN_DIM 6
+
+/* Preamp state byte (0x17, wIdx 0x003F — full state, verified).
+ * NOTE 2026-08-26 (cap_reflevel3.pcap): the 0x0C "base" is NOT a
+ * constant — it is the Instr 3/4 REF-LEVEL bits (bits 2-3, +4dBu =
+ * 0x0C set; −10dBV/Boost = clear; Boost additionally commits 0x21
+ * wVal 0x0003). Keeping it always set = forcing the default +4dBu,
+ * which is correct for the driver (no ref-level control).
+ */
+#define BF_PREAMP_REF_4DBU 0x000c
+#define BF_PREAMP_BASE BF_PREAMP_REF_4DBU
+#define BF_PREAMP_48V_MIC1 0x0001
+#define BF_PREAMP_48V_MIC2 0x0002
+#define BF_PREAMP_PAD_MIC1 0x0010
+#define BF_PREAMP_PAD_MIC2 0x0020
+
+/* Calibrated master value: 0 dB = 0x2000 (+6 dB = 0x4000). See
+ * CALIBRATION.md. The crosspoint fader curve is DIFFERENT (0 dB =
+ * 0x16a0, top 0x2d41 — see below).
+ */
+#define BF_MASTER_0DB 0x2000
+
+/* The 8-bit master is the REAL output volume (hardware-verified
+ * 2026-08-24: writing it changes the level, the 16-bit does not).
+ * Scale: 0.5 dB per step, 0xf3 = 0 dB (the scene-load default),
+ * bottom 0x73 = -64 dB (silence), top 0xff = +6 dB. The 16-bit
+ * register is a companion kept in sync (TotalMix writes both).
+ * The mute value is 0x3B.
+ */
+#define BF_MASTER_8_0DB 0xf3
+#define BF_MASTER_8_MIN 0x73
+#define BF_MASTER_MUTE 0x3b
+#define BF_MASTER_UNMUTE 0xf3
+
+/* The front-panel gain/display family (0x1A, wIdx 0x000A + mic 0-3;
+ * cap_panel/cap_mix.pcap): in gain mode the wheel writes the "ADC
+ * gain" here (drives the same preamp as the GUI 0x0000+mic); in MIX
+ * (fader) mode the same registers carry the VU DISPLAY shadow —
+ * TotalMix writes the monitoring level display value (0..~31) and the
+ * card lights the input VU segments accordingly (hardware-verified
+ * 2026-08-26 live: sweeping 0x1A values moved the input VU).
+ */
+#define BF_REG_PANEL_GAIN 0x000a
+
+/* Crosspoint fader curve: 0 dB = 0x16a0, +6 dB = 0x2d41 (fader curve,
+ * DIFFERENT from the master 0x4000 top — see CALIBRATION.md).
+ */
+#define BF_FADER_0DB 0x16a0
+#define BF_FADER_TOP 0x2d41
+
+/* The crosspoint matrix sources (14 controls per output). */
+struct bf_source {
+ const char *name;
+ u8 idx_l;
+ u8 idx_r;
+};
+
+/* Crosspoint-source order + register block maps (babyfacepro-ctl.c). */
+extern const struct bf_source bf_sources[14];
+extern const u8 bf_xpoint_block[6];
+
+/* Calibrated preamp gain: 65 dB over 20 raw steps (3.25 dB/step). */
+#define BF_GAIN_MAX_DB 65
+
+struct snd_usb_babyface {
+ struct snd_card *card;
+ struct usb_device *dev;
+ struct usb_interface *iface;
+
+ struct mutex mutex; /* controls + stream geometry */
+ spinlock_t lock; /* hw_ptr / subs */
+
+ /* stream */
+ struct urb **urbs_in;
+ struct urb **urbs_out;
+ void **buf_in;
+ void **buf_out;
+ dma_addr_t *dma_in;
+ dma_addr_t *dma_out;
+ unsigned int nurbs;
+ unsigned int frames_per_urb;
+ unsigned int frame_bytes; /* 56/40/32 for alt 1/2/3 */
+ unsigned int rate;
+ unsigned int alt;
+ int stream_users; /* PCM substreams sharing the stream */
+ bool streaming; /* URBs actually in flight */
+ bool shutdown;
+ atomic_t urb_err; /* consecutive bad URBs (stops the stream) */
+ struct work_struct stream_work;
+
+ struct snd_pcm_substream *subs[2];
+ unsigned long hw_ptr[2];
+ unsigned long prev_period[2];
+
+ /* mixer state (no gain readback exists — host-side mirror) */
+ u16 preamp; /* 48V/PAD bits, base 0x0c */
+ u8 gain[4]; /* preamp gain in dB 0-65/9 (raw derived
+ * at write: mic 3.25 dB/step, instr
+ * 0.5 dB/step)
+ */
+ u8 gain_cycle; /* 0x20/0x00/0x40 transaction counter */
+ u8 flag_cnt; /* 0xc000/0x4000/0x8000/0x0000 */
+ u16 master[6][2]; /* cached 16-bit masters */
+ bool muted[6];
+ u16 dim_saved[2]; /* pre-DIM Phones master (out 1 L/R) */
+ bool dim; /* DIM engaged (fixed -20 dB on Phones) */
+ u16 xpoint[6][14][2]; /* cached crosspoints (out, src, L/R) */
+ int pitch; /* varispeed in 0.1% (-500..+500) */
+ bool loopback[6];
+ bool an12; /* AN 1>2 copy */
+ bool linked; /* AN1/2 input link */
+ bool ms_proc; /* MS processor engaged */
+ int width; /* width knob -100..+100 */
+ u16 fx_send; /* FX send level 0..0x1000 */
+
+ /* DSP EQ (babyfacepro-ctl.c) — 4 analog-input strips, params kept in state */
+ struct bf_eq_channel {
+ bool on; /* EQ engaged (else identity blocks) */
+ s32 slope_db; /* low-cut slope 6/12/18/24 (0 = off) */
+ s32 lc_hz; /* low-cut freq, 0 = off */
+ u32 lc_raw; /* cached 0x38 word */
+ u8 slope; /* cached slope byte (2^n - 1) */
+ s32 band_type[3]; /* 0 off, 1 bell, 2 low shelf, 3 high shelf */
+ s32 band_freq[3]; /* Hz */
+ s32 band_q[3]; /* Q x 100 */
+ s32 band_gain[3]; /* dB x 10 */
+ s32 words[3][4]; /* cached c0..c3 */
+ s32 shared; /* cached c4 (shared by the slots) */
+ } eq[4];
+
+ /* front panel (babyfacepro-ctl.c) — 0x17 readback poll */
+ struct delayed_work panel_work;
+ unsigned int panel_poll_ms; /* front-panel poll interval, module param */
+ u8 panel_prev[4]; /* last 0x17 snapshot */
+ bool panel_seen; /* first snapshot taken */
+ bool panel_select_armed; /* device SELECT cycle armed (IN switch disarms) */
+ unsigned long panel_start; /* jiffies at panel_start (boot re-assert) */
+ int panel_button; /* latched button event (consumed on get) */
+ int panel_wheel; /* accumulated wheel delta (consumed on get) */
+ int panel_in; /* enum: 0 unknown, 1 Ch1/2, 2 Ch3/4, 3 Opt */
+ int panel_out; /* enum: 0 unknown, 1 Ch1/2, 2 Phones, 3 Opt */
+ bool panel_mix; /* MIX engaged — HOST-latched (like TotalMix):
+ * set by the 0x44 flash ack, NOT by the readback
+ * 0x80 bit (the raw press has none)
+ */
+ bool panel_dim; /* DIM sticky (byte1 bit 0x20) */
+ bool panel_saw_fader; /* device observed in fader mode (byte2 0x0x)
+ * — gates the device-driven MIX exit
+ */
+ int panel_select; /* SELECT state: 0 L, 1 R, 2 both, 3 none
+ * (host-tracked — not in the readback)
+ */
+ int panel_sel_hold; /* consecutive ticks with byte3 = 0x50
+ * (SELECT held > 200 ms = the OUT-balance
+ * gesture; a tap flashes only ~100-150 ms,
+ * selhold_probe2 — no engaged bit)
+ */
+ u16 panel_mix_raw; /* MIX-mode monitoring level (fader raw) */
+ u8 panel_mix_disp[4]; /* MIX-mode VU display shadow per mic
+ * (0x1A 0x000A+mic — written on change
+ * so the input VU follows the wheel)
+ */
+ struct snd_kcontrol *panel_kctl[7]; /* for snd_ctl_notify */
+};
+
+struct bf_saved {
+ struct list_head list;
+ char key[32];
+ u16 preamp;
+ u8 gain[4];
+ u8 gain_cycle;
+ u8 flag_cnt;
+ u16 master[6][2];
+ bool muted[6];
+ u16 xpoint[6][14][2];
+ int pitch;
+ bool loopback[6];
+ bool an12;
+ bool linked;
+ bool ms_proc;
+ int width;
+ u16 fx_send;
+ bool dim;
+};
+
+struct bf_rate {
+ unsigned int rate;
+ unsigned int alt;
+ unsigned int frame_bytes;
+ unsigned int min_fpu; /* frames/URB floor = one alt packet (448/640/1024 B) */
+};
+
+/* Sample-rate / alt classes (babyfacepro.c). */
+const struct bf_rate *bf_rate_lookup(unsigned int rate);
+
+/* ── shared driver state ────────────────────── */
+extern const u16 bf_flag_cycle[4];
+extern const struct bf_source bf_sources[14];
+
+/* babyfacepro-ctl.c — the DSP EQ (struct snd_usb_babyface is defined above). */
+void bf_eq_band_words(s32 *w, int type, s32 freq_hz, s32 q100,
+ s32 gain_x10, s32 fs);
+void bf_eq_reupload(struct snd_usb_babyface *chip);
+int babyface_create_eq(struct snd_usb_babyface *chip);
+extern const u8 bf_xpoint_block[6];
+extern const struct snd_pcm_hw_constraint_list bf_rates_constraint;
+
+/* ── babyfacepro.c ──────────────────────── */
+int bf_vendor_write(struct snd_usb_babyface *chip, u8 req, u16 val, u16 idx);
+int bf_vendor_read(struct snd_usb_babyface *chip, u8 req, u16 idx, u8 *buf);
+int bf_cold_init(struct snd_usb_babyface *chip);
+int bf_crosspoint_clear_cross(struct snd_usb_babyface *chip,
+ unsigned int blk);
+const struct bf_rate *bf_rate_lookup(unsigned int rate);
+void babyface_stream_kill(struct snd_usb_babyface *chip);
+void babyface_pcm_stop_both(struct snd_usb_babyface *chip, snd_pcm_state_t state);
+void babyface_stream_work(struct work_struct *work);
+
+/* ── babyfacepro-ctl.c ─────────────────────── */
+int babyface_write_default_mixer(struct snd_usb_babyface *chip);
+int bf_apply_masters(struct snd_usb_babyface *chip);
+int bf_loopback_write_map(struct snd_usb_babyface *chip, int out, bool on);
+int bf_preamp_state_write(struct snd_usb_babyface *chip);
+int babyface_create_controls(struct snd_usb_babyface *chip);
+int babyface_create_xpoints(struct snd_usb_babyface *chip);
+int babyface_create_flags(struct snd_usb_babyface *chip);
+
+/* Master + gain law helpers — shared with the front-panel wheels. */
+int bf_master_half_db(u16 vol16); /* 16-bit master → dB×2 */
+int bf_master_16bit(int half_db); /* dB×2 → 16-bit master */
+u8 bf_master_8bit(u16 vol16); /* 16-bit master → 8-bit companion */
+int bf_gain_max_db(int mic);
+int bf_gain_db(int mic, u8 raw); u8 bf_gain_raw(int mic, int db);
+
+/* ── babyfacepro-ctl.c ─────────────────────── */
+int babyface_create_panel(struct snd_usb_babyface *chip);
+void babyface_panel_start(struct snd_usb_babyface *chip);
+void babyface_panel_stop(struct snd_usb_babyface *chip);
+void babyface_panel_work(struct work_struct *work);
+
+/* ── babyfacepro.c ──────────────────────── */
+void bf_state_save(struct snd_usb_babyface *chip);
+int bf_state_restore(struct snd_usb_babyface *chip);
+void bf_state_purge(void);
+int babyface_restore_state(struct snd_usb_babyface *chip);
+int bf_state_apply_flags(struct snd_usb_babyface *chip);
--
2.55.0
next prev parent reply other threads:[~2026-08-29 10:03 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-29 10:03 [RFC PATCH 0/1] RME Babyface Pro FS driver (proprietary mode) Ismaïl Bahloul
2026-08-29 10:03 ` Ismaïl Bahloul [this message]
2026-08-31 14:11 ` Takashi Iwai
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