// SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2025 serifpersia /* * ALSA Driver for TASCAM US-144MKII Audio Interface */ #include #include #include #include #include #include MODULE_AUTHOR("serifpersia "); MODULE_DESCRIPTION("ALSA Driver for TASCAM US-144MKII"); MODULE_LICENSE("GPL v2"); #define DRIVER_NAME "us144mkii" #define DRIVER_VERSION "1.5" /* * TODO: * - Implement MIDI IN/OUT. */ /* --- Module Parameters --- */ static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; static bool enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0}; static int dev_idx; /* --- USB Device Identification --- */ #define USB_VID_TASCAM 0x0644 #define USB_PID_TASCAM_US144MKII 0x8020 /* --- USB Endpoints (Alternate Setting 1) --- */ #define EP_PLAYBACK_FEEDBACK 0x81 #define EP_AUDIO_OUT 0x02 #define EP_MIDI_IN 0x83 #define EP_MIDI_OUT 0x04 #define EP_AUDIO_IN 0x86 /* --- USB Control Message Protocol --- */ #define RT_H2D_CLASS_EP (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT) #define RT_D2H_CLASS_EP (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT) #define RT_H2D_VENDOR_DEV (USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE) #define RT_D2H_VENDOR_DEV (USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE) #define UAC_SET_CUR 0x01 #define UAC_GET_CUR 0x81 #define UAC_SAMPLING_FREQ_CONTROL 0x0100 #define VENDOR_REQ_REGISTER_WRITE 0x41 #define VENDOR_REQ_MODE_CONTROL 0x49 #define MODE_VAL_HANDSHAKE_READ 0x0000 #define MODE_VAL_CONFIG 0x0010 #define MODE_VAL_STREAM_START 0x0030 #define HANDSHAKE_SUCCESS_VAL 0x12 #define REG_ADDR_UNKNOWN_0D 0x0d04 #define REG_ADDR_UNKNOWN_0E 0x0e00 #define REG_ADDR_UNKNOWN_0F 0x0f00 #define REG_ADDR_RATE_44100 0x1000 #define REG_ADDR_RATE_48000 0x1002 #define REG_ADDR_RATE_88200 0x1008 #define REG_ADDR_RATE_96000 0x100a #define REG_ADDR_UNKNOWN_11 0x110b #define REG_VAL_ENABLE 0x0101 /* --- URB Configuration --- */ #define NUM_PLAYBACK_URBS 8 #define PLAYBACK_URB_PACKETS 4 #define NUM_FEEDBACK_URBS 4 #define MAX_FEEDBACK_PACKETS 5 #define FEEDBACK_PACKET_SIZE 3 #define NUM_CAPTURE_URBS 8 #define CAPTURE_URB_SIZE 512 #define CAPTURE_RING_BUFFER_SIZE (CAPTURE_URB_SIZE * NUM_CAPTURE_URBS * 4) #define USB_CTRL_TIMEOUT_MS 1000 /* --- Audio Format Configuration --- */ #define BYTES_PER_SAMPLE 3 #define NUM_CHANNELS 4 #define BYTES_PER_FRAME (NUM_CHANNELS * BYTES_PER_SAMPLE) #define FEEDBACK_ACCUMULATOR_SIZE 128 /* --- Capture Decoding Defines --- */ #define DECODED_CHANNELS_PER_FRAME 4 #define DECODED_SAMPLE_SIZE 4 /* 32-bit */ #define FRAMES_PER_DECODE_BLOCK 8 #define RAW_BYTES_PER_DECODE_BLOCK 512 /* --- Main Driver Data Structure --- */ struct tascam_card { struct usb_device *dev; struct usb_interface *iface0; struct usb_interface *iface1; struct snd_card *card; struct snd_pcm *pcm; struct snd_pcm_substream *playback_substream; struct urb *playback_urbs[NUM_PLAYBACK_URBS]; size_t playback_urb_alloc_size; struct snd_pcm_substream *capture_substream; atomic_t capture_active; snd_pcm_uframes_t driver_capture_pos; u64 capture_frames_processed; u64 last_capture_period_pos; u8 *capture_ring_buffer; size_t capture_ring_buffer_read_ptr; volatile size_t capture_ring_buffer_write_ptr; u8 *capture_decode_raw_block; s32 *capture_decode_dst_block; struct work_struct capture_work; struct urb *feedback_urbs[NUM_FEEDBACK_URBS]; size_t feedback_urb_alloc_size; spinlock_t lock; atomic_t active_urbs; int current_rate; unsigned int latency_profile; unsigned int line_out_source; /* 0: Playback 1-2, 1: Playback 3-4 */ unsigned int digital_out_source; /* 0: Playback 1-2, 1: Playback 3-4 */ unsigned int capture_12_source; /* 0: Analog In, 1: Digital In */ unsigned int capture_34_source; /* 0: Analog In, 1: Digital In */ unsigned int feedback_accumulator_pattern[FEEDBACK_ACCUMULATOR_SIZE]; unsigned int feedback_pattern_out_idx; unsigned int feedback_pattern_in_idx; bool feedback_synced; unsigned int feedback_consecutive_errors; unsigned int feedback_urb_skip_count; u64 playback_frames_consumed; snd_pcm_uframes_t driver_playback_pos; u64 last_period_pos; u64 capture_frames_produced; u64 last_capture_period_pos; const unsigned int (*feedback_patterns)[8]; unsigned int feedback_base_value; unsigned int feedback_max_value; }; static struct usb_driver tascam_alsa_driver; /* --- Forward Declarations --- */ static void playback_urb_complete(struct urb *urb); static void feedback_urb_complete(struct urb *urb); static void capture_urb_complete(struct urb *urb); static void tascam_capture_work_handler(struct work_struct *work); static int us144mkii_configure_device_for_rate(struct tascam_card *tascam, int rate); static int tascam_probe(struct usb_interface *intf, const struct usb_device_id *id); static void tascam_disconnect(struct usb_interface *intf); static int tascam_suspend(struct usb_interface *intf, pm_message_t message); static int tascam_resume(struct usb_interface *intf); /* --- Sysfs Attribute for Driver Version --- */ /** * driver_version_show - Sysfs callback to show the driver version. * @dev: The device structure. * @attr: The device attribute structure. * @buf: The buffer to write the version string into. * * Returns: The number of bytes written. */ static ssize_t driver_version_show(struct device *dev, struct device_attribute *attr, char *buf) { return sysfs_emit(buf, "%s\n", DRIVER_VERSION); } static DEVICE_ATTR_RO(driver_version); /* --- ALSA Control Definitions --- */ /* --- ALSA Control Definitions --- */ static const char * const latency_profile_texts[] = {"Low", "Normal", "High"}; static const char * const playback_source_texts[] = {"Playback 1-2", "Playback 3-4"}; static const char * const capture_source_texts[] = {"Analog In", "Digital In"}; static int tascam_latency_info(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo) { uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED; uinfo->count = 1; uinfo->value.enumerated.items = 3; if (uinfo->value.enumerated.item >= 3) uinfo->value.enumerated.item = 2; strcpy(uinfo->value.enumerated.name, latency_profile_texts[uinfo->value.enumerated.item]); return 0; } static int tascam_latency_get(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol) { struct tascam_card *tascam = snd_kcontrol_chip(kcontrol); ucontrol->value.enumerated.item[0] = tascam->latency_profile; return 0; } static int tascam_latency_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol) { struct tascam_card *tascam = snd_kcontrol_chip(kcontrol); unsigned int new_profile = ucontrol->value.enumerated.item[0]; if (new_profile >= 3) return -EINVAL; if (tascam->latency_profile != new_profile) { tascam->latency_profile = new_profile; return 1; } return 0; } static const struct snd_kcontrol_new tascam_latency_control = { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = "Latency Profile", .info = tascam_latency_info, .get = tascam_latency_get, .put = tascam_latency_put, }; static int tascam_playback_source_info(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo) { uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED; uinfo->count = 1; uinfo->value.enumerated.items = 2; if (uinfo->value.enumerated.item >= 2) uinfo->value.enumerated.item = 1; strcpy(uinfo->value.enumerated.name, playback_source_texts[uinfo->value.enumerated.item]); return 0; } static int tascam_line_out_get(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol) { struct tascam_card *tascam = snd_kcontrol_chip(kcontrol); ucontrol->value.enumerated.item[0] = tascam->line_out_source; return 0; } static int tascam_line_out_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol) { struct tascam_card *tascam = snd_kcontrol_chip(kcontrol); if (ucontrol->value.enumerated.item[0] > 1) return -EINVAL; if (tascam->line_out_source == ucontrol->value.enumerated.item[0]) return 0; tascam->line_out_source = ucontrol->value.enumerated.item[0]; return 1; } static const struct snd_kcontrol_new tascam_line_out_control = { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = "Line Out Source", .info = tascam_playback_source_info, .get = tascam_line_out_get, .put = tascam_line_out_put, }; static int tascam_digital_out_get(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol) { struct tascam_card *tascam = snd_kcontrol_chip(kcontrol); ucontrol->value.enumerated.item[0] = tascam->digital_out_source; return 0; } static int tascam_digital_out_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol) { struct tascam_card *tascam = snd_kcontrol_chip(kcontrol); if (ucontrol->value.enumerated.item[0] > 1) return -EINVAL; if (tascam->digital_out_source == ucontrol->value.enumerated.item[0]) return 0; tascam->digital_out_source = ucontrol->value.enumerated.item[0]; return 1; } static const struct snd_kcontrol_new tascam_digital_out_control = { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = "Digital Out Source", .info = tascam_playback_source_info, .get = tascam_digital_out_get, .put = tascam_digital_out_put, }; static int tascam_capture_source_info(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo) { uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED; uinfo->count = 1; uinfo->value.enumerated.items = 2; if (uinfo->value.enumerated.item >= 2) uinfo->value.enumerated.item = 1; strcpy(uinfo->value.enumerated.name, capture_source_texts[uinfo->value.enumerated.item]); return 0; } static int tascam_capture_12_get(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol) { struct tascam_card *tascam = snd_kcontrol_chip(kcontrol); ucontrol->value.enumerated.item[0] = tascam->capture_12_source; return 0; } static int tascam_capture_12_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol) { struct tascam_card *tascam = snd_kcontrol_chip(kcontrol); if (ucontrol->value.enumerated.item[0] > 1) return -EINVAL; if (tascam->capture_12_source == ucontrol->value.enumerated.item[0]) return 0; tascam->capture_12_source = ucontrol->value.enumerated.item[0]; return 1; } static const struct snd_kcontrol_new tascam_capture_12_control = { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = "Capture 1-2 Source", .info = tascam_capture_source_info, .get = tascam_capture_12_get, .put = tascam_capture_12_put, }; static int tascam_capture_34_get(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol) { struct tascam_card *tascam = snd_kcontrol_chip(kcontrol); ucontrol->value.enumerated.item[0] = tascam->capture_34_source; return 0; } static int tascam_capture_34_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol) { struct tascam_card *tascam = snd_kcontrol_chip(kcontrol); if (ucontrol->value.enumerated.item[0] > 1) return -EINVAL; if (tascam->capture_34_source == ucontrol->value.enumerated.item[0]) return 0; tascam->capture_34_source = ucontrol->value.enumerated.item[0]; return 1; } static const struct snd_kcontrol_new tascam_capture_34_control = { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = "Capture 3-4 Source", .info = tascam_capture_source_info, .get = tascam_capture_34_get, .put = tascam_capture_34_put, }; /** * tascam_samplerate_info - ALSA control info callback for the sample rate. * @kcontrol: The kcontrol instance. * @uinfo: The user control element info structure to fill. * * Provides information about the read-only sample rate control. * * Returns: 0 on success. */ static int tascam_samplerate_info(struct snd_kcontrol *kcontrol, 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 = 96000; return 0; } /** * tascam_samplerate_get - ALSA control get callback for the sample rate. * @kcontrol: The kcontrol instance. * @ucontrol: The user control element value structure to fill. * * Reports the current sample rate of the device. It first checks the driver's * internal state. If no stream is active, it queries the device directly via * a USB control message. * * Returns: 0 on success, or a negative error code on failure. */ static int tascam_samplerate_get(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol) { struct tascam_card *tascam = (struct tascam_card *)snd_kcontrol_chip(kcontrol); u8 *buf; int err; u32 rate = 0; if (tascam->current_rate > 0) { ucontrol->value.integer.value[0] = tascam->current_rate; return 0; } buf = kmalloc(3, GFP_KERNEL); if (!buf) return -ENOMEM; err = usb_control_msg(tascam->dev, usb_rcvctrlpipe(tascam->dev, 0), UAC_GET_CUR, RT_D2H_CLASS_EP, UAC_SAMPLING_FREQ_CONTROL, EP_AUDIO_IN, buf, 3, USB_CTRL_TIMEOUT_MS); if (err >= 3) rate = buf[0] | (buf[1] << 8) | (buf[2] << 16); ucontrol->value.integer.value[0] = rate; kfree(buf); return 0; } static const struct snd_kcontrol_new tascam_samplerate_control = { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = "Sample Rate", .info = tascam_samplerate_info, .get = tascam_samplerate_get, .access = SNDRV_CTL_ELEM_ACCESS_READ, }; /* --- Rate-to-Packet Fixing Data (Verified) --- */ static const unsigned int patterns_48khz[5][8] = { {5, 6, 6, 6, 5, 6, 6, 6}, {5, 6, 6, 6, 6, 6, 6, 6}, {6, 6, 6, 6, 6, 6, 6, 6}, {7, 6, 6, 6, 6, 6, 6, 6}, {7, 6, 6, 6, 7, 6, 6, 6} }; static const unsigned int patterns_96khz[5][8] = { {11, 12, 12, 12, 11, 12, 12, 12}, {11, 12, 12, 12, 12, 12, 12, 12}, {12, 12, 12, 12, 12, 12, 12, 12}, {13, 12, 12, 12, 12, 12, 12, 12}, {13, 12, 12, 12, 13, 12, 12, 12} }; static const unsigned int patterns_88khz[5][8] = { {10, 11, 11, 11, 10, 11, 11, 11}, {10, 11, 11, 11, 11, 11, 11, 11}, {11, 11, 11, 11, 11, 11, 11, 11}, {12, 11, 11, 11, 11, 11, 11, 11}, {12, 11, 11, 11, 12, 11, 11, 11} }; static const unsigned int patterns_44khz[5][8] = { {5, 5, 5, 6, 5, 5, 5, 6}, {5, 5, 6, 5, 5, 6, 5, 6}, {5, 6, 5, 6, 5, 6, 5, 6}, {6, 5, 6, 6, 5, 6, 5, 6}, {6, 6, 6, 5, 6, 6, 6, 5} }; static const struct snd_pcm_hardware tascam_pcm_hw = { .info = (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER | SNDRV_PCM_INFO_MMAP_VALID | SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME), .formats = SNDRV_PCM_FMTBIT_S24_3LE, .rates = (SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000), .rate_min = 44100, .rate_max = 96000, .channels_min = NUM_CHANNELS, .channels_max = NUM_CHANNELS, .buffer_bytes_max = 1024 * 1024, .period_bytes_min = 48 * BYTES_PER_FRAME, .period_bytes_max = 1024 * BYTES_PER_FRAME, .periods_min = 2, .periods_max = 1024, }; /** * tascam_free_urbs - Free all allocated URBs and associated buffers. * @tascam: the tascam_card instance. * * This function kills, unlinks, and frees all playback, feedback, and capture * URBs, along with their transfer buffers and the capture ring/decode buffers. */ static void tascam_free_urbs(struct tascam_card *tascam) { int i; for (i = 0; i < NUM_PLAYBACK_URBS; i++) { if (tascam->playback_urbs[i]) { usb_kill_urb(tascam->playback_urbs[i]); usb_free_coherent(tascam->dev, tascam->playback_urb_alloc_size, tascam->playback_urbs[i]->transfer_buffer, tascam->playback_urbs[i]->transfer_dma); usb_free_urb(tascam->playback_urbs[i]); tascam->playback_urbs[i] = NULL; } } for (i = 0; i < NUM_FEEDBACK_URBS; i++) { if (tascam->feedback_urbs[i]) { usb_kill_urb(tascam->feedback_urbs[i]); usb_free_coherent(tascam->dev, tascam->feedback_urb_alloc_size, tascam->feedback_urbs[i]->transfer_buffer, tascam->feedback_urbs[i]->transfer_dma); usb_free_urb(tascam->feedback_urbs[i]); tascam->feedback_urbs[i] = NULL; } } for (i = 0; i < NUM_CAPTURE_URBS; i++) { if (tascam->capture_urbs[i]) { usb_kill_urb(tascam->capture_urbs[i]); usb_free_coherent(tascam->dev, tascam->capture_urb_alloc_size, tascam->capture_urbs[i]->transfer_buffer, tascam->capture_urbs[i]->transfer_dma); usb_free_urb(tascam->capture_urbs[i]); tascam->capture_urbs[i] = NULL; } } kfree(tascam->capture_decode_dst_block); tascam->capture_decode_dst_block = NULL; kfree(tascam->capture_decode_raw_block); tascam->capture_decode_raw_block = NULL; kfree(tascam->capture_ring_buffer); tascam->capture_ring_buffer = NULL; } /** * tascam_alloc_urbs - Allocate all URBs and associated buffers. * @tascam: the tascam_card instance. * * This function allocates and initializes all URBs for playback, feedback, * and capture, as well as the necessary buffers for capture data processing. * * Return: 0 on success, or a negative error code on failure. */ static int tascam_alloc_urbs(struct tascam_card *tascam) { int i; size_t max_packet_size; max_packet_size = ((96000 / 8000) + 2) * BYTES_PER_FRAME; tascam->playback_urb_alloc_size = max_packet_size * PLAYBACK_URB_PACKETS; for (i = 0; i < NUM_PLAYBACK_URBS; i++) { struct urb *urb = usb_alloc_urb(PLAYBACK_URB_PACKETS, GFP_KERNEL); if (!urb) goto error; tascam->playback_urbs[i] = urb; urb->transfer_buffer = usb_alloc_coherent(tascam->dev, tascam->playback_urb_alloc_size, GFP_KERNEL, &urb->transfer_dma); if (!urb->transfer_buffer) goto error; urb->dev = tascam->dev; urb->pipe = usb_sndisocpipe(tascam->dev, EP_AUDIO_OUT); urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP; urb->interval = 1; urb->context = tascam; urb->complete = playback_urb_complete; } tascam->feedback_urb_alloc_size = FEEDBACK_PACKET_SIZE * MAX_FEEDBACK_PACKETS; for (i = 0; i < NUM_FEEDBACK_URBS; i++) { struct urb *f_urb = usb_alloc_urb(MAX_FEEDBACK_PACKETS, GFP_KERNEL); if (!f_urb) goto error; tascam->feedback_urbs[i] = f_urb; f_urb->transfer_buffer = usb_alloc_coherent(tascam->dev, tascam->feedback_urb_alloc_size, GFP_KERNEL, &f_urb->transfer_dma); if (!f_urb->transfer_buffer) goto error; f_urb->dev = tascam->dev; f_urb->pipe = usb_rcvisocpipe(tascam->dev, EP_PLAYBACK_FEEDBACK); f_urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP; f_urb->interval = 4; f_urb->context = tascam; f_urb->complete = feedback_urb_complete; } tascam->capture_urb_alloc_size = CAPTURE_URB_SIZE; for (i = 0; i < NUM_CAPTURE_URBS; i++) { struct urb *c_urb = usb_alloc_urb(0, GFP_KERNEL); if (!c_urb) goto error; tascam->capture_urbs[i] = c_urb; c_urb->transfer_buffer = usb_alloc_coherent(tascam->dev, tascam->capture_urb_alloc_size, GFP_KERNEL, &c_urb->transfer_dma); if (!c_urb->transfer_buffer) goto error; usb_fill_bulk_urb(c_urb, tascam->dev, usb_rcvbulkpipe(tascam->dev, EP_AUDIO_IN), c_urb->transfer_buffer, tascam->capture_urb_alloc_size, capture_urb_complete, tascam); c_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; } tascam->capture_ring_buffer = kmalloc(CAPTURE_RING_BUFFER_SIZE, GFP_KERNEL); if (!tascam->capture_ring_buffer) goto error; tascam->capture_decode_raw_block = kmalloc(RAW_BYTES_PER_DECODE_BLOCK, GFP_KERNEL); if (!tascam->capture_decode_raw_block) goto error; tascam->capture_decode_dst_block = kmalloc(FRAMES_PER_DECODE_BLOCK * DECODED_CHANNELS_PER_FRAME * DECODED_SAMPLE_SIZE, GFP_KERNEL); if (!tascam->capture_decode_dst_block) goto error; return 0; error: dev_err(tascam->card->dev, "Failed to allocate URBs\n"); tascam_free_urbs(tascam); return -ENOMEM; } static int tascam_pcm_open(struct snd_pcm_substream *substream) { struct tascam_card *tascam = snd_pcm_substream_chip(substream); struct snd_pcm_runtime *runtime = substream->runtime; int err; runtime->hw = tascam_pcm_hw; tascam->playback_substream = substream; atomic_set(&tascam->playback_active, 0); err = tascam_alloc_urbs(tascam); if (err < 0) return err; return 0; } static int tascam_pcm_close(struct snd_pcm_substream *substream) { struct tascam_card *tascam = snd_pcm_substream_chip(substream); tascam_free_urbs(tascam); return 0; } /** * us144mkii_configure_device_for_rate - Send USB control messages to set sample rate. * @tascam: the tascam_card instance. * @rate: the target sample rate (e.g., 44100, 96000). * * This function sends a sequence of vendor-specific and UAC control messages * to configure the device hardware for the specified sample rate. * * Return: 0 on success, or a negative error code on failure. */ static int us144mkii_configure_device_for_rate(struct tascam_card *tascam, int rate) { struct usb_device *dev = tascam->dev; u8 *rate_payload_buf; u16 rate_vendor_wValue; int err = 0; static const u8 payload_44100[] = {0x44, 0xac, 0x00}; static const u8 payload_48000[] = {0x80, 0xbb, 0x00}; static const u8 payload_88200[] = {0x88, 0x58, 0x01}; static const u8 payload_96000[] = {0x00, 0x77, 0x01}; const u8 *current_payload_src; switch (rate) { case 44100: current_payload_src = payload_44100; rate_vendor_wValue = REG_ADDR_RATE_44100; break; case 48000: current_payload_src = payload_48000; rate_vendor_wValue = REG_ADDR_RATE_48000; break; case 88200: current_payload_src = payload_88200; rate_vendor_wValue = REG_ADDR_RATE_88200; break; case 96000: current_payload_src = payload_96000; rate_vendor_wValue = REG_ADDR_RATE_96000; break; default: dev_err(&dev->dev, "Unsupported sample rate %d for configuration\n", rate); return -EINVAL; } rate_payload_buf = kmemdup(current_payload_src, 3, GFP_KERNEL); if (!rate_payload_buf) return -ENOMEM; dev_info(&dev->dev, "Configuring device for %d Hz\n", rate); err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), VENDOR_REQ_MODE_CONTROL, RT_H2D_VENDOR_DEV, MODE_VAL_CONFIG, 0x0000, NULL, 0, USB_CTRL_TIMEOUT_MS); if (err < 0) goto fail; err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR, RT_H2D_CLASS_EP, UAC_SAMPLING_FREQ_CONTROL, EP_AUDIO_IN, rate_payload_buf, 3, USB_CTRL_TIMEOUT_MS); if (err < 0) goto fail; err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR, RT_H2D_CLASS_EP, UAC_SAMPLING_FREQ_CONTROL, EP_AUDIO_OUT, rate_payload_buf, 3, USB_CTRL_TIMEOUT_MS); if (err < 0) goto fail; err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), VENDOR_REQ_REGISTER_WRITE, RT_H2D_VENDOR_DEV, REG_ADDR_UNKNOWN_0D, REG_VAL_ENABLE, NULL, 0, USB_CTRL_TIMEOUT_MS); if (err < 0) goto fail; err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), VENDOR_REQ_REGISTER_WRITE, RT_H2D_VENDOR_DEV, REG_ADDR_UNKNOWN_0E, REG_VAL_ENABLE, NULL, 0, USB_CTRL_TIMEOUT_MS); if (err < 0) goto fail; err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), VENDOR_REQ_REGISTER_WRITE, RT_H2D_VENDOR_DEV, REG_ADDR_UNKNOWN_0F, REG_VAL_ENABLE, NULL, 0, USB_CTRL_TIMEOUT_MS); if (err < 0) goto fail; err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), VENDOR_REQ_REGISTER_WRITE, RT_H2D_VENDOR_DEV, rate_vendor_wValue, REG_VAL_ENABLE, NULL, 0, USB_CTRL_TIMEOUT_MS); if (err < 0) goto fail; err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), VENDOR_REQ_REGISTER_WRITE, RT_H2D_VENDOR_DEV, REG_ADDR_UNKNOWN_11, REG_VAL_ENABLE, NULL, 0, USB_CTRL_TIMEOUT_MS); if (err < 0) goto fail; err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), VENDOR_REQ_MODE_CONTROL, RT_H2D_VENDOR_DEV, MODE_VAL_STREAM_START, 0x0000, NULL, 0, USB_CTRL_TIMEOUT_MS); if (err < 0) goto fail; kfree(rate_payload_buf); return 0; fail: dev_err(&dev->dev, "Device configuration failed at rate %d with error %d\n", rate, err); kfree(rate_payload_buf); return err; } static int tascam_pcm_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params) { struct tascam_card *tascam = snd_pcm_substream_chip(substream); int err; unsigned int rate = params_rate(params); err = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params)); if (err < 0) return err; /* Set rate-dependent feedback patterns and values */ switch (rate) { case 44100: tascam->feedback_patterns = patterns_44khz; tascam->feedback_base_value = 42; tascam->feedback_max_value = 46; break; case 48000: tascam->feedback_patterns = patterns_48khz; tascam->feedback_base_value = 46; tascam->feedback_max_value = 50; break; case 88200: tascam->feedback_patterns = patterns_88khz; tascam->feedback_base_value = 86; tascam->feedback_max_value = 90; break; case 96000: tascam->feedback_patterns = patterns_96khz; tascam->feedback_base_value = 94; tascam->feedback_max_value = 98; break; default: return -EINVAL; } /* Always re-configure hardware to ensure it's in a clean state */ err = us144mkii_configure_device_for_rate(tascam, rate); if (err < 0) { tascam->current_rate = 0; return err; } tascam->current_rate = rate; return 0; } static int tascam_pcm_hw_free(struct snd_pcm_substream *substream) { return snd_pcm_lib_free_pages(substream); } static int tascam_pcm_prepare(struct snd_pcm_substream *substream) { struct tascam_card *tascam = snd_pcm_substream_chip(substream); struct snd_pcm_runtime *runtime = substream->runtime; int i, u; size_t nominal_frames_per_packet, nominal_bytes_per_packet; size_t total_bytes_in_urb; unsigned int feedback_packets; /* Reset driver state for the new stream */ tascam->driver_playback_pos = 0; tascam->playback_frames_consumed = 0; tascam->last_period_pos = 0; tascam->feedback_pattern_in_idx = 0; tascam->feedback_pattern_out_idx = 0; tascam->feedback_synced = false; tascam->feedback_consecutive_errors = 0; tascam->feedback_urb_skip_count = NUM_FEEDBACK_URBS; /* Initialize feedback accumulator with nominal values */ nominal_frames_per_packet = runtime->rate / 8000; for (i = 0; i < FEEDBACK_ACCUMULATOR_SIZE; i++) tascam->feedback_accumulator_pattern[i] = nominal_frames_per_packet; /* Validate and apply latency profile */ switch (tascam->latency_profile) { case 0: feedback_packets = 1; break; /* Low */ case 1: feedback_packets = 2; break; /* Normal */ case 2: feedback_packets = 5; break; /* High */ default: feedback_packets = 2; } /* Configure Feedback URBs */ for (i = 0; i < NUM_FEEDBACK_URBS; i++) { struct urb *f_urb = tascam->feedback_urbs[i]; int j; f_urb->number_of_packets = feedback_packets; f_urb->transfer_buffer_length = feedback_packets * FEEDBACK_PACKET_SIZE; for (j = 0; j < feedback_packets; j++) { f_urb->iso_frame_desc[j].offset = j * FEEDBACK_PACKET_SIZE; f_urb->iso_frame_desc[j].length = FEEDBACK_PACKET_SIZE; } } /* Configure Playback URBs */ nominal_bytes_per_packet = nominal_frames_per_packet * BYTES_PER_FRAME; total_bytes_in_urb = nominal_bytes_per_packet * PLAYBACK_URB_PACKETS; for (u = 0; u < NUM_PLAYBACK_URBS; u++) { struct urb *urb = tascam->playback_urbs[u]; memset(urb->transfer_buffer, 0, tascam->playback_urb_alloc_size); urb->transfer_buffer_length = total_bytes_in_urb; urb->number_of_packets = PLAYBACK_URB_PACKETS; for (i = 0; i < PLAYBACK_URB_PACKETS; i++) { urb->iso_frame_desc[i].offset = i * nominal_bytes_per_packet; urb->iso_frame_desc[i].length = nominal_bytes_per_packet; } } return 0; } static int tascam_capture_prepare(struct snd_pcm_substream *substream) { struct tascam_card *tascam = snd_pcm_substream_chip(substream); tascam->driver_capture_pos = 0; tascam->capture_frames_processed = 0; tascam->last_capture_period_pos = 0; tascam->capture_ring_buffer_read_ptr = 0; tascam->capture_ring_buffer_write_ptr = 0; return 0; } static int tascam_pcm_trigger(struct snd_pcm_substream *substream, int cmd) { struct tascam_card *tascam = snd_pcm_substream_chip(substream); unsigned long flags; int err = 0; int i; bool do_start = false; bool do_stop = false; spin_lock_irqsave(&tascam->lock, flags); switch (cmd) { case SNDRV_PCM_TRIGGER_START: case SNDRV_PCM_TRIGGER_RESUME: if (!atomic_read(&tascam->playback_active)) { atomic_set(&tascam->playback_active, 1); atomic_set(&tascam->capture_active, 1); do_start = true; } break; case SNDRV_PCM_TRIGGER_STOP: case SNDRV_PCM_TRIGGER_SUSPEND: case SNDRV_PCM_TRIGGER_PAUSE_PUSH: if (atomic_read(&tascam->playback_active)) { atomic_set(&tascam->playback_active, 0); atomic_set(&tascam->capture_active, 0); do_stop = true; } break; default: err = -EINVAL; break; } spin_unlock_irqrestore(&tascam->lock, flags); if (do_start) { if (atomic_read(&tascam->active_urbs) > 0) { dev_warn(tascam->card->dev, "Cannot start, URBs still active.\n"); return -EAGAIN; } for (i = 0; i < NUM_FEEDBACK_URBS; i++) { err = usb_submit_urb(tascam->feedback_urbs[i], GFP_ATOMIC); if (err < 0) goto start_rollback; atomic_inc(&tascam->active_urbs); } for (i = 0; i < NUM_PLAYBACK_URBS; i++) { err = usb_submit_urb(tascam->playback_urbs[i], GFP_ATOMIC); if (err < 0) goto start_rollback; atomic_inc(&tascam->active_urbs); } for (i = 0; i < NUM_CAPTURE_URBS; i++) { err = usb_submit_urb(tascam->capture_urbs[i], GFP_ATOMIC); if (err < 0) goto start_rollback; atomic_inc(&tascam->active_urbs); } return 0; start_rollback: dev_err(tascam->card->dev, "Failed to submit URBs to start stream: %d\n", err); do_stop = true; } if (do_stop) { for (i = 0; i < NUM_PLAYBACK_URBS; i++) { usb_unlink_urb(tascam->playback_urbs[i]); atomic_dec(&tascam->active_urbs); } for (i = 0; i < NUM_FEEDBACK_URBS; i++) { usb_unlink_urb(tascam->feedback_urbs[i]); atomic_dec(&tascam->active_urbs); } for (i = 0; i < NUM_CAPTURE_URBS; i++) { usb_unlink_urb(tascam->capture_urbs[i]); atomic_dec(&tascam->active_urbs); } cancel_work_sync(&tascam->capture_work); } return err; } static snd_pcm_uframes_t tascam_pcm_pointer(struct snd_pcm_substream *substream) { struct tascam_card *tascam = snd_pcm_substream_chip(substream); struct snd_pcm_runtime *runtime = substream->runtime; u64 pos; unsigned long flags; if (!atomic_read(&tascam->playback_active)) return 0; spin_lock_irqsave(&tascam->lock, flags); pos = tascam->playback_frames_consumed; spin_unlock_irqrestore(&tascam->lock, flags); return runtime ? pos % runtime->buffer_size : 0; } static snd_pcm_uframes_t tascam_capture_pointer(struct snd_pcm_substream *substream) { struct tascam_card *tascam = snd_pcm_substream_chip(substream); struct snd_pcm_runtime *runtime = substream->runtime; u64 pos; unsigned long flags; if (!atomic_read(&tascam->capture_active)) return 0; spin_lock_irqsave(&tascam->lock, flags); pos = tascam->capture_frames_processed; spin_unlock_irqrestore(&tascam->lock, flags); return runtime ? pos % runtime->buffer_size : 0; } static struct snd_pcm_ops tascam_playback_ops = { .open = tascam_playback_open, .close = tascam_playback_close, .ioctl = snd_pcm_lib_ioctl, .hw_params = tascam_pcm_hw_params, .hw_free = tascam_pcm_hw_free, .prepare = tascam_playback_prepare, .trigger = tascam_pcm_trigger, .pointer = tascam_playback_pointer, }; static struct snd_pcm_ops tascam_capture_ops = { .open = tascam_capture_open, .close = tascam_capture_close, .ioctl = snd_pcm_lib_ioctl, .hw_params = tascam_pcm_hw_params, .hw_free = tascam_pcm_hw_free, .prepare = tascam_capture_prepare, .trigger = tascam_pcm_trigger, .pointer = tascam_capture_pointer, }; /** * playback_urb_complete - Completion handler for playback isochronous URBs. * @urb: the completed URB. * * This function runs in interrupt context. It calculates the number of bytes * to send in the next set of packets based on the feedback-driven clock, * copies the audio data from the ALSA ring buffer (applying routing), and * resubmits the URB. */ static void playback_urb_complete(struct urb *urb) { struct tascam_card *tascam = urb->context; struct snd_pcm_substream *substream; struct snd_pcm_runtime *runtime; unsigned long flags; char *src_buf, *dst_buf; size_t total_bytes_for_urb = 0; snd_pcm_uframes_t offset_frames; snd_pcm_uframes_t frames_to_copy; int ret, i; if (urb->status) { if (urb->status != -ENOENT && urb->status != -ECONNRESET && urb->status != -ESHUTDOWN) dev_err_ratelimited(tascam->card->dev, "Playback URB failed: %d\n", urb->status); return; } if (!tascam || !atomic_read(&tascam->playback_active)) return; substream = tascam->playback_substream; if (!substream || !substream->runtime) return; runtime = substream->runtime; spin_lock_irqsave(&tascam->lock, flags); /* Phase 1: Populate the isochronous frame descriptors from the accumulator. */ for (i = 0; i < urb->number_of_packets; i++) { unsigned int frames_for_packet; size_t bytes_for_packet; if (tascam->feedback_synced) { frames_for_packet = tascam->feedback_accumulator_pattern[tascam->feedback_pattern_out_idx]; tascam->feedback_pattern_out_idx = (tascam->feedback_pattern_out_idx + 1) % FEEDBACK_ACCUMULATOR_SIZE; } else { frames_for_packet = runtime->rate / 8000; } bytes_for_packet = frames_for_packet * BYTES_PER_FRAME; urb->iso_frame_desc[i].offset = total_bytes_for_urb; urb->iso_frame_desc[i].length = bytes_for_packet; total_bytes_for_urb += bytes_for_packet; } urb->transfer_buffer_length = total_bytes_for_urb; /* Phase 2: Atomically update the driver's position. */ offset_frames = tascam->driver_playback_pos; frames_to_copy = bytes_to_frames(runtime, total_bytes_for_urb); tascam->driver_playback_pos = (offset_frames + frames_to_copy) % runtime->buffer_size; /* --- End of Critical Section --- */ spin_unlock_irqrestore(&tascam->lock, flags); /* Phase 3: Perform the data copy OUTSIDE the lock. */ if (total_bytes_for_urb > 0) { int f; src_buf = runtime->dma_area; dst_buf = urb->transfer_buffer; for (f = 0; f < frames_to_copy; ++f) { snd_pcm_uframes_t current_frame_pos = (offset_frames + f) % runtime->buffer_size; char *src_frame = src_buf + frames_to_bytes(runtime, current_frame_pos); char *dst_frame = dst_buf + (f * BYTES_PER_FRAME); char *src_12 = src_frame; char *src_34 = src_frame + 6; char *dst_line_out = dst_frame; char *dst_digital_out = dst_frame + 6; if (tascam->line_out_source == 0) memcpy(dst_line_out, src_12, 6); else memcpy(dst_line_out, src_34, 6); if (tascam->digital_out_source == 0) memcpy(dst_digital_out, src_12, 6); else memcpy(dst_digital_out, src_34, 6); } } urb->dev = tascam->dev; ret = usb_submit_urb(urb, GFP_ATOMIC); if (ret < 0) dev_err_ratelimited(tascam->card->dev, "Failed to resubmit playback URB: %d\n", ret); } /** * feedback_urb_complete - Completion handler for feedback isochronous URBs. * @urb: the completed URB. * * This is the master clock for the driver. It runs in interrupt context. * It reads the feedback value from the device, which indicates how many * samples the device has consumed. This information is used to adjust the * playback rate and to advance the capture stream pointer, keeping both * streams in sync. It then calls snd_pcm_period_elapsed if necessary and * resubmits itself. */ static void feedback_urb_complete(struct urb *urb) { struct tascam_card *tascam = urb->context; struct snd_pcm_substream *playback_ss, *capture_ss; struct snd_pcm_runtime *playback_rt, *capture_rt; unsigned long flags; u64 total_frames_in_urb = 0; int ret, p; unsigned int old_in_idx, new_in_idx; bool playback_period_elapsed = false; bool capture_period_elapsed = false; if (urb->status) { if (urb->status != -ENOENT && urb->status != -ECONNRESET && urb->status != -ESHUTDOWN) dev_err_ratelimited(tascam->card->dev, "Feedback URB failed: %d\n", urb->status); return; } if (!tascam || !atomic_read(&tascam->playback_active)) return; playback_ss = tascam->playback_substream; if (!playback_ss || !playback_ss->runtime) return; playback_rt = playback_ss->runtime; capture_ss = tascam->capture_substream; capture_rt = capture_ss ? capture_ss->runtime : NULL; spin_lock_irqsave(&tascam->lock, flags); /* Hybrid Sync: Initial blind period for hardware to settle. */ if (tascam->feedback_urb_skip_count > 0) { tascam->feedback_urb_skip_count--; goto unlock_and_continue; } old_in_idx = tascam->feedback_pattern_in_idx; for (p = 0; p < urb->number_of_packets; p++) { u8 feedback_value = 0; const unsigned int *pattern; bool packet_ok = (urb->iso_frame_desc[p].status == 0 && urb->iso_frame_desc[p].actual_length >= 1); if (packet_ok) feedback_value = *((u8 *)urb->transfer_buffer + urb->iso_frame_desc[p].offset); if (packet_ok && feedback_value >= tascam->feedback_base_value && feedback_value <= tascam->feedback_max_value) { pattern = tascam->feedback_patterns[feedback_value - tascam->feedback_base_value]; tascam->feedback_consecutive_errors = 0; int i; for (i = 0; i < 8; i++) { unsigned int in_idx = (tascam->feedback_pattern_in_idx + i) % FEEDBACK_ACCUMULATOR_SIZE; tascam->feedback_accumulator_pattern[in_idx] = pattern[i]; total_frames_in_urb += pattern[i]; } } else { unsigned int nominal_frames = playback_rt->rate / 8000; int i; if (tascam->feedback_synced) { tascam->feedback_consecutive_errors++; if (tascam->feedback_consecutive_errors > 10) { dev_warn_ratelimited(tascam->card->dev, "Feedback sync lost! (value: %u, errors: %u)\n", feedback_value, tascam->feedback_consecutive_errors); tascam->feedback_synced = false; } } for (i = 0; i < 8; i++) { unsigned int in_idx = (tascam->feedback_pattern_in_idx + i) % FEEDBACK_ACCUMULATOR_SIZE; tascam->feedback_accumulator_pattern[in_idx] = nominal_frames; total_frames_in_urb += nominal_frames; } } tascam->feedback_pattern_in_idx = (tascam->feedback_pattern_in_idx + 8) % FEEDBACK_ACCUMULATOR_SIZE; } new_in_idx = tascam->feedback_pattern_in_idx; if (!tascam->feedback_synced) { unsigned int out_idx = tascam->feedback_pattern_out_idx; bool is_ahead = (new_in_idx - out_idx) % FEEDBACK_ACCUMULATOR_SIZE < (FEEDBACK_ACCUMULATOR_SIZE / 2); bool was_behind = (old_in_idx - out_idx) % FEEDBACK_ACCUMULATOR_SIZE >= (FEEDBACK_ACCUMULATOR_SIZE / 2); if (is_ahead && was_behind) { dev_dbg(tascam->card->dev, "Sync Acquired! (in: %u, out: %u)\n", new_in_idx, out_idx); tascam->feedback_synced = true; tascam->feedback_consecutive_errors = 0; } } if (total_frames_in_urb > 0) { tascam->playback_frames_consumed += total_frames_in_urb; if (atomic_read(&tascam->capture_active)) tascam->capture_frames_processed += total_frames_in_urb; } if (playback_rt->period_size > 0) { u64 current_period = div_u64(tascam->playback_frames_consumed, playback_rt->period_size); if (current_period > tascam->last_period_pos) { tascam->last_period_pos = current_period; playback_period_elapsed = true; } } if (atomic_read(&tascam->capture_active) && capture_rt && capture_rt->period_size > 0) { u64 current_capture_period = div_u64(tascam->capture_frames_processed, capture_rt->period_size); if (current_capture_period > tascam->last_capture_period_pos) { tascam->last_capture_period_pos = current_capture_period; capture_period_elapsed = true; } } unlock_and_continue: spin_unlock_irqrestore(&tascam->lock, flags); if (playback_period_elapsed) snd_pcm_period_elapsed(playback_ss); if (capture_period_elapsed) snd_pcm_period_elapsed(capture_ss); urb->dev = tascam->dev; ret = usb_submit_urb(urb, GFP_ATOMIC); if (ret < 0) dev_err_ratelimited(tascam->card->dev, "Failed to resubmit feedback URB: %d\n", ret); } /** * decode_tascam_capture_block - Decodes a raw 512-byte block from the device. * @src_block: Pointer to the 512-byte raw source block. * @dst_block: Pointer to the destination buffer for decoded audio frames. * * The device sends audio data in a complex, multiplexed format. This function * demultiplexes the bits from the raw block into 8 frames of 4-channel, * 24-bit audio (stored in 32-bit containers). */ static void decode_tascam_capture_block(const u8 *src_block, s32 *dst_block) { int frame, bit; memset(dst_block, 0, FRAMES_PER_DECODE_BLOCK * DECODED_CHANNELS_PER_FRAME * DECODED_SAMPLE_SIZE); for (frame = 0; frame < FRAMES_PER_DECODE_BLOCK; ++frame) { const u8 *p_src_frame_base = src_block + frame * 64; s32 *p_dst_frame = dst_block + frame * 4; s32 ch[4] = {0}; for (bit = 0; bit < 24; ++bit) { u8 byte1 = p_src_frame_base[bit]; u8 byte2 = p_src_frame_base[bit + 32]; ch[0] = (ch[0] << 1) | (byte1 & 1); ch[2] = (ch[2] << 1) | ((byte1 >> 1) & 1); ch[1] = (ch[1] << 1) | (byte2 & 1); ch[3] = (ch[3] << 1) | ((byte2 >> 1) & 1); } /* The result is a 24-bit sample. Shift left by 8 to align it to * the most significant bits of a 32-bit integer (S32_LE format). */ p_dst_frame[0] = ch[0] << 8; p_dst_frame[1] = ch[1] << 8; p_dst_frame[2] = ch[2] << 8; p_dst_frame[3] = ch[3] << 8; } } /** * tascam_capture_work_handler - Deferred work handler for processing capture data. * @work: the work_struct instance. * * This function runs in a kernel thread context, not an IRQ context. It reads * raw data from the capture ring buffer, decodes it, applies routing, and * copies the final audio data into the ALSA capture ring buffer. This offloads * the CPU-intensive decoding from the time-sensitive URB completion handlers. */ static void tascam_capture_work_handler(struct work_struct *work) { struct tascam_card *tascam = container_of(work, struct tascam_card, capture_work); struct snd_pcm_substream *substream = tascam->capture_substream; struct snd_pcm_runtime *runtime; unsigned long flags; if (!substream || !substream->runtime) return; runtime = substream->runtime; u8 *raw_block = tascam->capture_decode_raw_block; s32 *decoded_block = tascam->capture_decode_dst_block; if (!raw_block || !decoded_block) { dev_err(tascam->card->dev, "Capture decode buffers not allocated!\n"); return; } if (runtime->period_size > 0) { u64 current_period = div_u64(tascam->playback_frames_consumed, runtime->period_size); if (current_period > tascam->last_period_pos) { tascam->last_period_pos = current_period; playback_period_elapsed = true; } spin_unlock_irqrestore(&tascam->lock, flags); if (!can_process) break; decode_tascam_capture_block(raw_block, decoded_block); spin_lock_irqsave(&tascam->lock, flags); if (atomic_read(&tascam->capture_active)) { int f; for (f = 0; f < FRAMES_PER_DECODE_BLOCK; ++f) { s32 *decoded_frame = decoded_block + (f * DECODED_CHANNELS_PER_FRAME); char *dst_frame = runtime->dma_area + frames_to_bytes(runtime, tascam->driver_capture_pos); s32 *src_analog = decoded_frame; s32 *src_digital = decoded_frame + 2; /* The decoded samples are in S32_LE format. The ALSA format is * S24_3LE. We copy the 3 least significant bytes by starting * the memcpy from the second byte of the 32-bit integer. */ if (tascam->capture_12_source == 0) { memcpy(dst_frame, ((char *)src_analog) + 1, 3); // Ch1 from Analog 1 memcpy(dst_frame + 3, ((char *)(src_analog + 1)) + 1, 3); // Ch2 from Analog 2 } else { memcpy(dst_frame, ((char *)src_digital) + 1, 3); // Ch1 from Digital 1 memcpy(dst_frame + 3, ((char *)(src_digital + 1)) + 1, 3); // Ch2 from Digital 2 } /* Since the device has only two analog inputs, channels 3-4 can be * sourced from a copy of the analog inputs or the digital input. */ if (tascam->capture_34_source == 0) { memcpy(dst_frame + 6, ((char *)src_analog) + 1, 3); // Ch3 from Analog 1 memcpy(dst_frame + 9, ((char *)(src_analog + 1)) + 1, 3); // Ch4 from Analog 2 } else { memcpy(dst_frame + 6, ((char *)src_digital) + 1, 3); // Ch3 from Digital 1 memcpy(dst_frame + 9, ((char *)(src_digital + 1)) + 1, 3); // Ch4 from Digital 2 } tascam->driver_capture_pos++; if (tascam->driver_capture_pos >= runtime->buffer_size) tascam->driver_capture_pos = 0; } } spin_unlock_irqrestore(&tascam->lock, flags); } } /** * capture_urb_complete - Completion handler for capture bulk URBs. * @urb: the completed URB. * * This function runs in interrupt context. It copies the received raw data * into an intermediate ring buffer and then schedules the workqueue to process * it. It then resubmits the URB to receive more data. */ static void capture_urb_complete(struct urb *urb) { struct tascam_card *tascam = urb->context; int ret; unsigned long flags; if (urb->status) { if (urb->status != -ENOENT && urb->status != -ECONNRESET && urb->status != -ESHUTDOWN) dev_err_ratelimited(tascam->card->dev, "Capture URB failed: %d\n", urb->status); return; } if (!tascam || !atomic_read(&tascam->capture_active)) return; if (urb->actual_length > 0) { size_t i; size_t write_ptr; spin_lock_irqsave(&tascam->lock, flags); write_ptr = tascam->capture_ring_buffer_write_ptr; for (i = 0; i < urb->actual_length; i++) { tascam->capture_ring_buffer[write_ptr] = ((u8 *)urb->transfer_buffer)[i]; write_ptr = (write_ptr + 1) % CAPTURE_RING_BUFFER_SIZE; } tascam->capture_ring_buffer_write_ptr = write_ptr; spin_unlock_irqrestore(&tascam->lock, flags); schedule_work(&tascam->capture_work); } urb->dev = tascam->dev; ret = usb_submit_urb(urb, GFP_ATOMIC); if (ret < 0) dev_err_ratelimited(tascam->card->dev, "Failed to resubmit feedback URB: %d\n", ret); } static int tascam_create_pcm(struct tascam_card *tascam) { struct snd_pcm *pcm; int err; err = snd_pcm_new(tascam->card, "US144MKII", 0, 1, 1, &pcm); if (err < 0) return err; err = snd_ctl_add(tascam->card, snd_ctl_new1(&tascam_latency_control, tascam)); if (err < 0) return err; err = snd_ctl_add(tascam->card, snd_ctl_new1(&tascam_line_out_control, tascam)); if (err < 0) return err; err = snd_ctl_add(tascam->card, snd_ctl_new1(&tascam_digital_out_control, tascam)); if (err < 0) return err; err = snd_ctl_add(tascam->card, snd_ctl_new1(&tascam_capture_12_control, tascam)); if (err < 0) return err; err = snd_ctl_add(tascam->card, snd_ctl_new1(&tascam_capture_34_control, tascam)); if (err < 0) return err; err = snd_ctl_add(tascam->card, snd_ctl_new1(&tascam_samplerate_control, tascam)); if (err < 0) return err; tascam->pcm = pcm; pcm->private_data = tascam; snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &tascam_playback_ops); snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &tascam_capture_ops); snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS, tascam->dev->dev.parent, 64 * 1024, tascam_pcm_hw.buffer_bytes_max); return 0; } static void tascam_card_private_free(struct snd_card *card) { struct tascam_card *tascam = card->private_data; if (tascam && tascam->dev) { usb_put_dev(tascam->dev); tascam->dev = NULL; } } static int tascam_suspend(struct usb_interface *intf, pm_message_t message) { struct tascam_card *tascam = usb_get_intfdata(intf); if (!tascam || !tascam->pcm) return 0; snd_pcm_suspend_all(tascam->pcm); cancel_work_sync(&tascam->capture_work); return 0; } static int tascam_resume(struct usb_interface *intf) { struct tascam_card *tascam = usb_get_intfdata(intf); struct usb_device *dev; int err; if (!tascam) return 0; dev = tascam->dev; dev_info(&intf->dev, "Resuming and re-initializing device...\n"); /* Re-establish alternate settings for both interfaces */ err = usb_set_interface(dev, 0, 1); if (err < 0) { dev_err(&intf->dev, "Resume: Set Alt Setting on Intf 0 failed: %d\n", err); return err; } err = usb_set_interface(dev, 1, 1); if (err < 0) { dev_err(&intf->dev, "Resume: Set Alt Setting on Intf 1 failed: %d\n", err); return err; } /* Re-configure the device for the last used sample rate. */ if (tascam->current_rate > 0) { dev_info(&intf->dev, "Restoring sample rate to %d Hz\n", tascam->current_rate); err = us144mkii_configure_device_for_rate(tascam, tascam->current_rate); if (err < 0) { dev_err(&intf->dev, "Resume: Failed to restore sample rate configuration\n"); tascam->current_rate = 0; return err; } } return 0; } /** * tascam_probe - Entry point for when the USB device is detected. * @intf: the USB interface that was matched. * @usb_id: the matching USB device ID. * * This function is called by the USB core when a device matching the driver's * ID table is connected. It allocates the sound card, initializes the driver * data structure, claims interfaces, sets up the device, creates the PCM * and control interfaces, and registers the sound card with ALSA. * * Return: 0 on success, or a negative error code on failure. */ static int tascam_probe(struct usb_interface *intf, const struct usb_device_id *usb_id) { struct usb_device *dev = interface_to_usbdev(intf); struct tascam_card *tascam; struct snd_card *card; int err; u8 *handshake_buf; if (intf->cur_altsetting->desc.bInterfaceNumber != 0) return -ENODEV; if (dev_idx >= SNDRV_CARDS) return -ENODEV; if (!enable[dev_idx]) { dev_idx++; return -ENOENT; } err = snd_card_new(&intf->dev, index[dev_idx], id[dev_idx], THIS_MODULE, sizeof(struct tascam_card), &card); if (err < 0) return err; tascam = card->private_data; tascam->card = card; tascam->dev = usb_get_dev(dev); tascam->iface0 = intf; card->private_free = tascam_card_private_free; usb_set_intfdata(intf, tascam); spin_lock_init(&tascam->lock); atomic_set(&tascam->active_urbs, 0); INIT_WORK(&tascam->capture_work, tascam_capture_work_handler); tascam->latency_profile = 1; tascam->line_out_source = 0; tascam->digital_out_source = 1; tascam->capture_12_source = 0; tascam->capture_34_source = 1; tascam->current_rate = 0; /* Not known until hw_params */ strscpy(card->driver, DRIVER_NAME, sizeof(card->driver)); strscpy(card->shortname, "TASCAM US-144MKII", sizeof(card->shortname)); snprintf(card->longname, sizeof(card->longname), "TASCAM US-144MKII (VID:%04x, PID:%04x) at %s", le16_to_cpu(dev->descriptor.idVendor), le16_to_cpu(dev->descriptor.idProduct), dev->bus->bus_name); tascam->iface1 = usb_ifnum_to_if(dev, 1); if (!tascam->iface1) { dev_err(&intf->dev, "Interface 1 not found.\n"); err = -ENODEV; goto free_card_obj; } err = usb_driver_claim_interface(&tascam_alsa_driver, tascam->iface1, tascam); if (err < 0) { dev_err(&intf->dev, "Could not claim interface 1: %d\n", err); tascam->iface1 = NULL; goto free_card_obj; } err = usb_set_interface(dev, 0, 1); if (err < 0) { dev_err(&intf->dev, "Set Alt Setting on Intf 0 failed: %d\n", err); goto release_iface1_and_free_card; } err = usb_set_interface(dev, 1, 1); if (err < 0) { dev_err(&intf->dev, "Set Alt Setting on Intf 1 failed: %d\n", err); goto release_iface1_and_free_card; } handshake_buf = kmalloc(1, GFP_KERNEL); if (!handshake_buf) { err = -ENOMEM; goto release_iface1_and_free_card; } err = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), VENDOR_REQ_MODE_CONTROL, RT_D2H_VENDOR_DEV, MODE_VAL_HANDSHAKE_READ, 0x0000, handshake_buf, 1, USB_CTRL_TIMEOUT_MS); if (err == 1 && handshake_buf[0] == HANDSHAKE_SUCCESS_VAL) dev_info(&intf->dev, "Handshake successful.\n"); else dev_warn(&intf->dev, "Handshake failed (err %d, val 0x%02x), continuing anyway.\n", err, err > 0 ? handshake_buf[0] : 0); kfree(handshake_buf); err = tascam_create_pcm(tascam); if (err < 0) goto release_iface1_and_free_card; if (device_create_file(&intf->dev, &dev_attr_driver_version)) dev_warn(&intf->dev, "Could not create sysfs attribute for driver version\n"); err = snd_card_register(card); if (err < 0) goto release_iface1_and_free_card; dev_info(&intf->dev, "TASCAM US-144MKII driver initialized.\n"); dev_idx++; return 0; release_iface1_and_free_card: if (tascam->iface1) { usb_set_intfdata(tascam->iface1, NULL); usb_driver_release_interface(&tascam_alsa_driver, tascam->iface1); tascam->iface1 = NULL; } free_card_obj: snd_card_free(card); return err; } /** * tascam_disconnect - Entry point for when the USB device is disconnected. * @intf: the USB interface being disconnected. * * This function is called by the USB core when the device is removed. It * cancels any pending work, disconnects the sound card from ALSA, releases * claimed interfaces, and schedules the card structure to be freed. */ static void tascam_disconnect(struct usb_interface *intf) { struct tascam_card *tascam = usb_get_intfdata(intf); if (!tascam) return; device_remove_file(&intf->dev, &dev_attr_driver_version); if (intf != tascam->iface0) return; dev_info(&intf->dev, "TASCAM US-144MKII disconnecting...\n"); snd_card_disconnect(tascam->card); cancel_work_sync(&tascam->capture_work); if (tascam->iface1) { usb_set_intfdata(tascam->iface1, NULL); usb_driver_release_interface(&tascam_alsa_driver, tascam->iface1); tascam->iface1 = NULL; } /* Decrement the device index to allow the next probe to use this slot. */ if (dev_idx > 0) dev_idx--; snd_card_free_when_closed(tascam->card); } static const struct usb_device_id tascam_id_table[] = { { USB_DEVICE(USB_VID_TASCAM, USB_PID_TASCAM_US144MKII) }, { } }; MODULE_DEVICE_TABLE(usb, tascam_id_table); static struct usb_driver tascam_alsa_driver = { .name = DRIVER_NAME, .probe = tascam_probe, .disconnect = tascam_disconnect, .id_table = tascam_id_table, .suspend = tascam_suspend, .resume = tascam_resume, }; module_usb_driver(tascam_alsa_driver);