// SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2025 serifpersia /* * ALSA Driver for TASCAM US-144MKII Audio Interface */ #include #include #include #include #include #include #include #include #include MODULE_AUTHOR("serifpersia "); MODULE_DESCRIPTION("ALSA Driver for TASCAM US-144MKII"); MODULE_LICENSE("GPL"); #define DRIVER_NAME "snd-usb-us144mkii" /* * TODO: * - Implement audio input capture. * - Implement MIDI IN/OUT. * - Expose hardware features via the ALSA Control API (mixers): * - Digital output format selection. * - Input/output routing. */ /* --- 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; module_param_array(index, int, NULL, 0444); MODULE_PARM_DESC(index, "Index value for the US-144MKII soundcard."); module_param_array(id, charp, NULL, 0444); MODULE_PARM_DESC(id, "ID string for the US-144MKII soundcard."); module_param_array(enable, bool, NULL, 0444); MODULE_PARM_DESC(enable, "Enable this US-144MKII soundcard."); /* --- 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_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_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 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 NUM_FEEDBACK_URBS 4 #define MAX_FEEDBACK_PACKETS 5 #define MAX_PLAYBACK_URB_ISO_PACKETS 8 #define FEEDBACK_PACKET_SIZE 3 #define USB_CTRL_TIMEOUT_MS 1000 /* --- Audio Format Configuration --- */ #define BYTES_PER_SAMPLE 3 #define NUM_CHANNELS 4 /* Changed: Match hardware for efficient copy */ #define BYTES_PER_FRAME (NUM_CHANNELS * BYTES_PER_SAMPLE) #define FEEDBACK_ACCUMULATOR_SIZE 128 struct tascam_card; 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 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); /* --- Rate-to-Packet Fixing Data --- */ 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} }; /* --- 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 urb *feedback_urbs[NUM_FEEDBACK_URBS]; size_t feedback_urb_alloc_size; spinlock_t lock; atomic_t playback_active; int current_rate; /* Stores the hardware profile index decided in hw_params for use in prepare */ int profile_idx; 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_urb_skip_count; u64 playback_frames_consumed; snd_pcm_uframes_t driver_playback_pos; u64 last_period_pos; const unsigned int (*feedback_patterns)[8]; unsigned int feedback_base_value; unsigned int feedback_max_value; }; 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, /* Changed: Expose 4 channels */ .channels_max = NUM_CHANNELS, /* Changed: Expose 4 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 their buffers. * @tascam: The card instance. * * This function is the counterpart to tascam_alloc_urbs. It is called * when the PCM device is closed to release all USB resources. */ 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; } } } /** * tascam_alloc_urbs - Allocate URBs and their buffers. * @tascam: The card instance. * * Allocates all necessary URBs for playback and feedback. This is called * when the PCM device is opened. * Returns: 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 * MAX_PLAYBACK_URB_ISO_PACKETS; for (i = 0; i < NUM_PLAYBACK_URBS; i++) { struct urb *urb = usb_alloc_urb(MAX_PLAYBACK_URB_ISO_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; } 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; } 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); unsigned int period_frames = params_period_size(params); /* Latency profile thresholds (in frames) based on hardware specification */ unsigned int profile_thresholds[5]; err = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params)); if (err < 0) return err; /* Set profile thresholds based on the selected sample rate */ switch (rate) { case 44100: profile_thresholds[0] = 49; /* Lowest */ profile_thresholds[1] = 64; /* Low */ profile_thresholds[2] = 128; /* Normal */ profile_thresholds[3] = 256; /* High */ profile_thresholds[4] = 512; /* Highest */ break; case 48000: profile_thresholds[0] = 48; profile_thresholds[1] = 64; profile_thresholds[2] = 128; profile_thresholds[3] = 256; profile_thresholds[4] = 512; break; case 88200: profile_thresholds[0] = 98; profile_thresholds[1] = 128; profile_thresholds[2] = 256; profile_thresholds[3] = 512; profile_thresholds[4] = 1024; break; case 96000: profile_thresholds[0] = 96; profile_thresholds[1] = 128; profile_thresholds[2] = 256; profile_thresholds[3] = 512; profile_thresholds[4] = 1024; break; default: return -EINVAL; } /* Map the application's requested period size to a hardware profile */ if (period_frames <= profile_thresholds[0]) tascam->profile_idx = 0; else if (period_frames <= profile_thresholds[1]) tascam->profile_idx = 1; else if (period_frames <= profile_thresholds[2]) tascam->profile_idx = 2; else if (period_frames <= profile_thresholds[3]) tascam->profile_idx = 3; else /* Anything larger falls into the highest latency profile */ tascam->profile_idx = 4; dev_info(tascam->card->dev, "User requested period of %u frames @ %u Hz, mapping to hardware profile %d\n", period_frames, rate, tascam->profile_idx); /* 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; } /* Re-configure hardware only if the sample rate has changed */ if (tascam->current_rate != rate) { 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 playback_urb_iso_packets; /* Feedback packet counts for each of the 5 hardware profiles */ static const unsigned int feedback_packets_for_profile[] = { 1, 1, 2, 5, 5 }; /* 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_urb_skip_count = NUM_FEEDBACK_URBS * 2; dev_dbg(tascam->card->dev, "Prepare: Sync state reset, starting in unsynced mode.\n"); /* 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; /* * Program URBs safely based on the configuration chosen in hw_params. * This is the correct location, as the stream is guaranteed to be stopped. */ /* Configure Feedback URBs with the correct number of packets for the profile */ for (i = 0; i < NUM_FEEDBACK_URBS; i++) { struct urb *f_urb = tascam->feedback_urbs[i]; unsigned int packets = feedback_packets_for_profile[tascam->profile_idx]; int j; f_urb->number_of_packets = packets; f_urb->transfer_buffer_length = packets * FEEDBACK_PACKET_SIZE; for (j = 0; j < 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. The number of packets is always 40, * as per the hardware specification. */ playback_urb_iso_packets = MAX_PLAYBACK_URB_ISO_PACKETS; nominal_bytes_per_packet = nominal_frames_per_packet * BYTES_PER_FRAME; total_bytes_in_urb = nominal_bytes_per_packet * playback_urb_iso_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_iso_packets; for (i = 0; i < playback_urb_iso_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_pcm_trigger(struct snd_pcm_substream *substream, int cmd) { struct tascam_card *tascam = snd_pcm_substream_chip(substream); int err = 0, i; bool start = false; switch (cmd) { case SNDRV_PCM_TRIGGER_START: case SNDRV_PCM_TRIGGER_RESUME: if (atomic_xchg(&tascam->playback_active, 1) == 0) start = true; break; case SNDRV_PCM_TRIGGER_STOP: case SNDRV_PCM_TRIGGER_SUSPEND: case SNDRV_PCM_TRIGGER_PAUSE_PUSH: atomic_set(&tascam->playback_active, 0); break; default: return -EINVAL; } if (start) { for (i = 0; i < NUM_FEEDBACK_URBS; i++) { err = usb_submit_urb(tascam->feedback_urbs[i], GFP_ATOMIC); if (err < 0) goto rollback; } for (i = 0; i < NUM_PLAYBACK_URBS; i++) { err = usb_submit_urb(tascam->playback_urbs[i], GFP_ATOMIC); if (err < 0) goto rollback; } } else { for (i = 0; i < NUM_PLAYBACK_URBS; i++) usb_unlink_urb(tascam->playback_urbs[i]); for (i = 0; i < NUM_FEEDBACK_URBS; i++) usb_unlink_urb(tascam->feedback_urbs[i]); } return 0; rollback: dev_err(tascam->card->dev, "Failed to submit URBs to start stream: %d\n", err); atomic_set(&tascam->playback_active, 0); for (i = 0; i < NUM_PLAYBACK_URBS; i++) usb_unlink_urb(tascam->playback_urbs[i]); for (i = 0; i < NUM_FEEDBACK_URBS; i++) usb_unlink_urb(tascam->feedback_urbs[i]); 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 struct snd_pcm_ops tascam_playback_ops = { .open = tascam_pcm_open, .close = tascam_pcm_close, .ioctl = snd_pcm_lib_ioctl, .hw_params = tascam_pcm_hw_params, .hw_free = tascam_pcm_hw_free, .prepare = tascam_pcm_prepare, .trigger = tascam_pcm_trigger, .pointer = tascam_pcm_pointer, }; static int tascam_capture_open_stub(struct snd_pcm_substream *s) { return -ENODEV; } static int tascam_capture_close_stub(struct snd_pcm_substream *s) { return 0; } static struct snd_pcm_ops tascam_capture_ops = { .open = tascam_capture_open_stub, .close = tascam_capture_close_stub, }; 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; unsigned int total_frames_for_urb = 0; size_t total_bytes_for_urb = 0; int ret, i; if (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: Calculate the total number of frames needed for this URB. * The number of frames per packet varies based on the feedback from the device. */ for (i = 0; i < urb->number_of_packets; i++) { unsigned int frames_for_packet; if (tascam->feedback_synced) { frames_for_packet = tascam->feedback_accumulator_pattern[ (tascam->feedback_pattern_out_idx + i) % FEEDBACK_ACCUMULATOR_SIZE]; } else { frames_for_packet = runtime->rate / 8000; } total_frames_for_urb += frames_for_packet; } total_bytes_for_urb = total_frames_for_urb * BYTES_PER_FRAME; /* * Phase 2: Perform an efficient bulk memory copy. * This replaces the inefficient per-frame copy loop. It handles the * wrap-around case for the ALSA circular buffer. */ src_buf = runtime->dma_area; dst_buf = urb->transfer_buffer; if (total_bytes_for_urb > 0) { snd_pcm_uframes_t offset_frames = tascam->driver_playback_pos; snd_pcm_uframes_t frames_to_end = runtime->buffer_size - offset_frames; size_t bytes_to_end = frames_to_bytes(runtime, frames_to_end); if (total_bytes_for_urb > bytes_to_end) { /* Data wraps around the end of the circular buffer */ memcpy(dst_buf, src_buf + frames_to_bytes(runtime, offset_frames), bytes_to_end); memcpy(dst_buf + bytes_to_end, src_buf, total_bytes_for_urb - bytes_to_end); } else { /* Data is in a single contiguous block */ memcpy(dst_buf, src_buf + frames_to_bytes(runtime, offset_frames), total_bytes_for_urb); } } tascam->driver_playback_pos = (tascam->driver_playback_pos + total_frames_for_urb) % runtime->buffer_size; /* * Phase 3: Populate the isochronous frame descriptors. * The USB controller requires the offset and length for each packet within the URB. */ urb->transfer_buffer_length = total_bytes_for_urb; total_bytes_for_urb = 0; /* Reuse as running offset */ 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; } spin_unlock_irqrestore(&tascam->lock, flags); 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); } static void feedback_urb_complete(struct urb *urb) { struct tascam_card *tascam = urb->context; struct snd_pcm_substream *substream; struct snd_pcm_runtime *runtime; unsigned long flags; u64 current_period, total_frames_in_urb = 0; bool was_synced, sync_lost_this_urb = false; int ret, p; if (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); if (urb->status != 0) { dev_warn_ratelimited(tascam->card->dev, "Feedback URB failed with status %d\n", urb->status); sync_lost_this_urb = true; goto update_sync_state; } if (tascam->feedback_urb_skip_count > 0) { tascam->feedback_urb_skip_count--; goto unlock_and_resubmit; } for (p = 0; p < urb->number_of_packets; p++) { u8 feedback_value; const unsigned int *pattern; if (urb->iso_frame_desc[p].status != 0 || urb->iso_frame_desc[p].actual_length < 1) { sync_lost_this_urb = true; continue; } feedback_value = *((u8 *)urb->transfer_buffer + urb->iso_frame_desc[p].offset); if (feedback_value >= tascam->feedback_base_value && feedback_value <= tascam->feedback_max_value) { pattern = tascam->feedback_patterns[feedback_value - tascam->feedback_base_value]; 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]; } tascam->feedback_pattern_in_idx = (tascam->feedback_pattern_in_idx + 8) % FEEDBACK_ACCUMULATOR_SIZE; } else { sync_lost_this_urb = true; total_frames_in_urb += runtime->rate / 1000; } } update_sync_state: was_synced = tascam->feedback_synced; if (sync_lost_this_urb) { if (was_synced) dev_dbg(tascam->card->dev, "Sync Lost!\n"); tascam->feedback_synced = false; } else { if (!was_synced) dev_dbg(tascam->card->dev, "Sync Acquired!\n"); tascam->feedback_synced = true; } if (total_frames_in_urb > 0) tascam->playback_frames_consumed += total_frames_in_urb; current_period = div_u64(tascam->playback_frames_consumed, runtime->period_size); if (current_period > tascam->last_period_pos) { tascam->last_period_pos = current_period; spin_unlock_irqrestore(&tascam->lock, flags); snd_pcm_period_elapsed(substream); goto resubmit; } unlock_and_resubmit: spin_unlock_irqrestore(&tascam->lock, flags); resubmit: 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 PCM", 0, 1, 1, &pcm); if (err < 0) return err; tascam->pcm = pcm; pcm->private_data = tascam; strscpy(pcm->name, "US-144MKII Audio", sizeof(pcm->name)); 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; } } /** * tascam_suspend - Called when the device is being suspended. * @intf: The USB interface. * @message: Power management message. * * Stops all active audio streams to prepare for system sleep. * * Returns: 0 on success. */ 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); return 0; } /** * tascam_resume - Called when the device is being resumed. * @intf: The USB interface. * * Re-initializes the device hardware after system resume, restoring its * alternate settings and sample rate configuration. This is necessary because * the device may lose its state during suspend. * * Returns: 0 on success, or a negative error code on failure. */ 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 no stream was ever started, current_rate will be 0, and we skip this. * The ALSA core will handle resuming the PCM streams, which will * trigger our .prepare and .trigger ops as needed. */ 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"); /* Invalidate the rate so the next hw_params will re-configure fully. */ tascam->current_rate = 0; return err; } } return 0; } 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); 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] == 0x12) 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; 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; } static void tascam_disconnect(struct usb_interface *intf) { struct tascam_card *tascam = usb_get_intfdata(intf); if (!tascam) return; if (intf != tascam->iface0) return; dev_info(&intf->dev, "TASCAM US-144MKII disconnecting...\n"); snd_card_disconnect(tascam->card); if (tascam->iface1) { usb_set_intfdata(tascam->iface1, NULL); usb_driver_release_interface(&tascam_alsa_driver, tascam->iface1); tascam->iface1 = NULL; } 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);