marvin
/
us144mkii
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

feat: working playback alsa kernel driver 

alsa kernel driver: playback works with glitches yet to be solved
This commit is contained in:
serifpersia 2025-06-24 21:31:23 +02:00
parent 92acb50c37
commit 1a3568fca7
6 changed files with 792 additions and 52 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
.gitignore vendored
View File

@ -3,7 +3,6 @@
# Object files # Object files
*.o *.o
*.ko
*.obj *.obj
*.elf *.elf

10
README.md
View File

@ -4,6 +4,16 @@ Current feat:
- Vendor Specific Config & Initialization, - Vendor Specific Config & Initialization,
- Working Playback with glitches due to missing feedback clock resync(maybe) - Working Playback with glitches due to missing feedback clock resync(maybe)
- migrated working playback(with some glitches still) to kernel ALSA driver
- To compile and run it follow these steps:
- Blacklist us122l driver in order to be able to use this custom driver
- Get your linux headers via your package manager
- cd to driver directory & run sudo insmod us144mk2.ko
- Under sound setting you should see TASCAM US144MKII device
- the device should produce audio playback with glitches
- The release alsa custom driver might not work on newer kernel versions currently its been written on
debian 12 6.1 kernel. You might need to compile kernel with `make` and sudo insmod it.
To run need pulseaudio and libusb, to compile you need dev packages like gcc to compile the src c code. To run need pulseaudio and libusb, to compile you need dev packages like gcc to compile the src c code.
debian: debian:

BIN
latest_alsa_kernel_driver/us144mk2.ko Normal file
View File

Binary file not shown.

88
src & scripts/tascam_fifo_streamer.c
View File

@ -1,5 +1,8 @@
// MIT License Copyright (c) 2025 serifpersia // MIT License Copyright (c) 2025 serifpersia
//
// Simple, non-synchronized playback driver.
// This version is a clean base, modified only to provide a ~1.0ms
// transfer buffer size for 48kHz and 96kHz sample rates.
#include <stdio.h> #include <stdio.h>
#include <stdlib.h> #include <stdlib.h>
@ -22,7 +25,6 @@
// --- USB Request Types --- // --- USB Request Types ---
#define RT_H2D_CLASS_EP 0x22 #define RT_H2D_CLASS_EP 0x22
#define RT_D2H_CLASS_EP 0xa2
#define RT_H2D_VENDOR_DEV 0x40 #define RT_H2D_VENDOR_DEV 0x40
#define RT_D2H_VENDOR_DEV 0xc0 #define RT_D2H_VENDOR_DEV 0xc0
@ -36,11 +38,8 @@
#define BYTES_PER_SAMPLE 3 #define BYTES_PER_SAMPLE 3
#define DEVICE_CHANNELS 4 #define DEVICE_CHANNELS 4
#define DEVICE_FRAME_SIZE (DEVICE_CHANNELS * BYTES_PER_SAMPLE) // 12 bytes #define DEVICE_FRAME_SIZE (DEVICE_CHANNELS * BYTES_PER_SAMPLE) // 12 bytes
#define PIPE_CHANNELS 2 #define PIPE_CHANNELS 2
#define PIPE_FRAME_SIZE (PIPE_CHANNELS * BYTES_PER_SAMPLE) // 6 bytes #define PIPE_FRAME_SIZE (PIPE_CHANNELS * BYTES_PER_SAMPLE) // 6 bytes
#define ISO_PACKETS_PER_TRANSFER 8
#define NUM_ISO_TRANSFERS 8 #define NUM_ISO_TRANSFERS 8
#define USB_TIMEOUT 1000 #define USB_TIMEOUT 1000
@ -56,7 +55,6 @@ int perform_initialization_sequence(libusb_device_handle *handle, int rate);
static void LIBUSB_CALL iso_playback_callback(struct libusb_transfer *transfer); static void LIBUSB_CALL iso_playback_callback(struct libusb_transfer *transfer);
static void LIBUSB_CALL feedback_callback(struct libusb_transfer *transfer); static void LIBUSB_CALL feedback_callback(struct libusb_transfer *transfer);
// --- Signal Handler ---
void sigint_handler(int signum) { void sigint_handler(int signum) {
if (is_running) { if (is_running) {
printf("\nCtrl+C detected, stopping...\n"); printf("\nCtrl+C detected, stopping...\n");
@ -64,7 +62,6 @@ void sigint_handler(int signum) {
} }
} }
// --- Main Program ---
int main(int argc, char *argv[]) { int main(int argc, char *argv[]) {
libusb_device_handle *handle = NULL; libusb_device_handle *handle = NULL;
struct libusb_transfer *playback_transfers[NUM_ISO_TRANSFERS] = {0}; struct libusb_transfer *playback_transfers[NUM_ISO_TRANSFERS] = {0};
@ -86,18 +83,22 @@ int main(int argc, char *argv[]) {
fprintf(stderr, "Error: Missing required arguments.\n"); fprintf(stderr, "Error: Missing required arguments.\n");
print_usage(argv[0]); return 1; print_usage(argv[0]); return 1;
} }
if (sample_rate != 44100 && sample_rate != 48000 && sample_rate != 88200 && sample_rate != 96000) { if (sample_rate != 48000 && sample_rate != 96000) {
fprintf(stderr, "Error: Sample rate %d is not supported.\n", sample_rate); return 1; fprintf(stderr, "Error: Sample rate %d is not supported. Use 48000 or 96000.\n", sample_rate); return 1;
} }
const int frames_per_packet_playback = (sample_rate > 48000) ? 12 : 6; // --- DYNAMIC BUFFER CALCULATION FOR 1.0ms LATENCY ---
const int playback_packet_size = frames_per_packet_playback * DEVICE_FRAME_SIZE; const int frames_per_transfer = sample_rate / 1000; // 48 for 48k, 96 for 96k
const int playback_transfer_size = playback_packet_size * ISO_PACKETS_PER_TRANSFER; const int playback_transfer_size = frames_per_transfer * DEVICE_FRAME_SIZE;
const int num_iso_packets = 8; // A reasonable default
const int playback_packet_size = playback_transfer_size / num_iso_packets;
// The feedback endpoint size is fixed and small
const int feedback_packet_size = 3; const int feedback_packet_size = 3;
const int feedback_transfer_size = feedback_packet_size * ISO_PACKETS_PER_TRANSFER; const int feedback_transfer_size = feedback_packet_size * num_iso_packets;
printf("Initializing TASCAM US-144 MKII for %d Hz...\n", sample_rate); printf("Initializing TASCAM US-144 MKII for %d Hz...\n", sample_rate);
printf(" Playback Pipe: %s (using Iso EP 0x%02x)\n", playback_pipe_path, EP_AUDIO_OUT); printf("Using transfer size of %d bytes (%d frames) for ~1.0ms latency.\n", playback_transfer_size, frames_per_transfer);
signal(SIGINT, sigint_handler); signal(SIGINT, sigint_handler);
if (libusb_init(NULL) < 0) return 1; if (libusb_init(NULL) < 0) return 1;
@ -120,18 +121,18 @@ int main(int argc, char *argv[]) {
if (state.playback_fifo_fd < 0) { perror("Opening playback FIFO failed"); r = 1; goto cleanup; } if (state.playback_fifo_fd < 0) { perror("Opening playback FIFO failed"); r = 1; goto cleanup; }
char drain_buf[1024]; while (read(state.playback_fifo_fd, drain_buf, sizeof(drain_buf)) > 0); char drain_buf[1024]; while (read(state.playback_fifo_fd, drain_buf, sizeof(drain_buf)) > 0);
printf("Starting playback stream (EP 0x%02x) and feedback stream (EP 0x%02x)...\n", EP_AUDIO_OUT, EP_PLAYBACK_FEEDBACK); printf("Starting playback and feedback streams...\n");
for (int i = 0; i < NUM_ISO_TRANSFERS; i++) { for (int i = 0; i < NUM_ISO_TRANSFERS; i++) {
playback_transfers[i] = libusb_alloc_transfer(ISO_PACKETS_PER_TRANSFER); playback_transfers[i] = libusb_alloc_transfer(num_iso_packets);
unsigned char *buf = malloc(playback_transfer_size); unsigned char *buf_p = malloc(playback_transfer_size);
memset(buf, 0, playback_transfer_size); memset(buf_p, 0, playback_transfer_size);
libusb_fill_iso_transfer(playback_transfers[i], handle, EP_AUDIO_OUT, buf, playback_transfer_size, ISO_PACKETS_PER_TRANSFER, iso_playback_callback, &state, USB_TIMEOUT); libusb_fill_iso_transfer(playback_transfers[i], handle, EP_AUDIO_OUT, buf_p, playback_transfer_size, num_iso_packets, iso_playback_callback, &state, USB_TIMEOUT);
libusb_set_iso_packet_lengths(playback_transfers[i], playback_packet_size); libusb_set_iso_packet_lengths(playback_transfers[i], playback_packet_size);
libusb_submit_transfer(playback_transfers[i]); libusb_submit_transfer(playback_transfers[i]);
feedback_transfers[i] = libusb_alloc_transfer(ISO_PACKETS_PER_TRANSFER); feedback_transfers[i] = libusb_alloc_transfer(num_iso_packets);
buf = malloc(feedback_transfer_size); unsigned char *buf_f = malloc(feedback_transfer_size);
libusb_fill_iso_transfer(feedback_transfers[i], handle, EP_PLAYBACK_FEEDBACK, buf, feedback_transfer_size, ISO_PACKETS_PER_TRANSFER, feedback_callback, NULL, USB_TIMEOUT); libusb_fill_iso_transfer(feedback_transfers[i], handle, EP_PLAYBACK_FEEDBACK, buf_f, feedback_transfer_size, num_iso_packets, feedback_callback, NULL, USB_TIMEOUT);
libusb_set_iso_packet_lengths(feedback_transfers[i], feedback_packet_size); libusb_set_iso_packet_lengths(feedback_transfers[i], feedback_packet_size);
libusb_submit_transfer(feedback_transfers[i]); libusb_submit_transfer(feedback_transfers[i]);
} }
@ -170,14 +171,16 @@ cleanup:
void print_usage(const char *prog_name) { void print_usage(const char *prog_name) {
fprintf(stderr, "Usage: %s -r <rate> --playback-pipe <path>\n", prog_name); fprintf(stderr, "Usage: %s -r <rate> --playback-pipe <path>\n", prog_name);
fprintf(stderr, " -r <rate> : Set sample rate. Supported: 44100, 48000, 88200, 96000.\n"); fprintf(stderr, " -r <rate> : Set sample rate. Supported: 48000, 96000.\n");
fprintf(stderr, " --playback-pipe <path>: Path to the named pipe for audio playback.\n"); fprintf(stderr, " --playback-pipe <path>: Path to the named pipe for audio playback.\n");
} }
static void LIBUSB_CALL feedback_callback(struct libusb_transfer *transfer) { static void LIBUSB_CALL feedback_callback(struct libusb_transfer *transfer) {
if (!is_running) return; if (!is_running) return;
if (transfer->status == LIBUSB_TRANSFER_COMPLETED) { if (transfer->status == LIBUSB_TRANSFER_COMPLETED) {
if (is_running) libusb_submit_transfer(transfer); if (is_running) {
libusb_submit_transfer(transfer);
}
} }
} }
@ -192,30 +195,30 @@ static void LIBUSB_CALL iso_playback_callback(struct libusb_transfer *transfer)
struct stream_state *state = transfer->user_data; struct stream_state *state = transfer->user_data;
int total_frames = transfer->length / DEVICE_FRAME_SIZE; int total_frames = transfer->length / DEVICE_FRAME_SIZE;
int bytes_to_read_from_fifo = total_frames * PIPE_FRAME_SIZE; int bytes_to_read_from_fifo = total_frames * PIPE_FRAME_SIZE;
unsigned char source_buf[bytes_to_read_from_fifo];
// Use a static buffer to avoid malloc/free in the callback
static unsigned char source_buf[8192];
if (bytes_to_read_from_fifo > sizeof(source_buf)) {
bytes_to_read_from_fifo = sizeof(source_buf);
}
ssize_t n = read(state->playback_fifo_fd, source_buf, bytes_to_read_from_fifo); ssize_t n = read(state->playback_fifo_fd, source_buf, bytes_to_read_from_fifo);
unsigned char *device_buf = transfer->buffer; unsigned char *device_buf = transfer->buffer;
memset(device_buf, 0, transfer->length);
if (n > 0) { if (n > 0) {
int frames_read = n / PIPE_FRAME_SIZE; int frames_read = n / PIPE_FRAME_SIZE;
unsigned char *src = source_buf; unsigned char *src = source_buf;
for (int i = 0; i < frames_read; i++) { for (int i = 0; i < frames_read; i++) {
memcpy(device_buf, src, PIPE_FRAME_SIZE); memcpy(device_buf, src, PIPE_FRAME_SIZE);
memset(device_buf + PIPE_FRAME_SIZE, 0, PIPE_FRAME_SIZE);
device_buf += DEVICE_FRAME_SIZE; device_buf += DEVICE_FRAME_SIZE;
src += PIPE_FRAME_SIZE; src += PIPE_FRAME_SIZE;
} }
if (n < bytes_to_read_from_fifo) {
memset(device_buf, 0, transfer->length - (frames_read * DEVICE_FRAME_SIZE));
}
} else {
memset(transfer->buffer, 0, transfer->length);
} }
if (is_running && libusb_submit_transfer(transfer) < 0) { if (is_running) {
fprintf(stderr, "Error resubmitting playback transfer\n"); libusb_submit_transfer(transfer);
is_running = false;
} }
} }
@ -225,21 +228,18 @@ int perform_initialization_sequence(libusb_device_handle *handle, int rate) {
uint16_t rate_vendor_wValue; uint16_t rate_vendor_wValue;
switch(rate) { switch(rate) {
case 44100: memcpy(rate_data, (unsigned char[]){0x44, 0xac, 0x00}, 3); rate_vendor_wValue = 0x1000; break;
case 48000: memcpy(rate_data, (unsigned char[]){0x80, 0xbb, 0x00}, 3); rate_vendor_wValue = 0x1002; break; case 48000: memcpy(rate_data, (unsigned char[]){0x80, 0xbb, 0x00}, 3); rate_vendor_wValue = 0x1002; break;
case 88200: memcpy(rate_data, (unsigned char[]){0x88, 0x58, 0x01}, 3); rate_vendor_wValue = 0x1008; break;
case 96000: memcpy(rate_data, (unsigned char[]){0x00, 0x77, 0x01}, 3); rate_vendor_wValue = 0x100a; break; case 96000: memcpy(rate_data, (unsigned char[]){0x00, 0x77, 0x01}, 3); rate_vendor_wValue = 0x100a; break;
default: fprintf(stderr, "Invalid sample rate for initialization.\n"); return -1; default: fprintf(stderr, "Invalid sample rate for initialization.\n"); return -1;
} }
printf("\n--- STARTING DEVICE CONFIGURATION (per Spec v5.0) ---\n"); printf("\n--- STARTING DEVICE CONFIGURATION ---\n");
#define CHECK(desc, call) \ #define CHECK(desc, call) \
r = (call); \ r = (call); \
if (r < 0) { fprintf(stderr, " [FAIL] %s: %s\n", desc, libusb_error_name(r)); return -1; } \ if (r < 0) { fprintf(stderr, " [FAIL] %s: %s\n", desc, libusb_error_name(r)); return -1; } \
else { printf(" [OK] %s (returned %d)\n", desc, r); } else { printf(" [OK] %s (returned %d)\n", desc, r); }
printf(" [INFO] Step 1: Set Interfaces (already done in main, re-verifying)\n");
r = libusb_set_configuration(handle, 1); r = libusb_set_configuration(handle, 1);
if (r < 0 && r != LIBUSB_ERROR_BUSY) { fprintf(stderr, " [FAIL] Set Configuration 1: %s\n", libusb_error_name(r)); return -1; } if (r < 0 && r != LIBUSB_ERROR_BUSY) { fprintf(stderr, " [FAIL] Set Configuration 1: %s\n", libusb_error_name(r)); return -1; }
for (int i=0; i<=1; i++) { for (int i=0; i<=1; i++) {
@ -248,27 +248,17 @@ int perform_initialization_sequence(libusb_device_handle *handle, int rate) {
r = libusb_set_interface_alt_setting(handle, i, 1); r = libusb_set_interface_alt_setting(handle, i, 1);
if (r < 0) { fprintf(stderr, " [FAIL] Set Alt Setting on Intf %d: %s\n", i, libusb_error_name(r)); return -1; } if (r < 0) { fprintf(stderr, " [FAIL] Set Alt Setting on Intf %d: %s\n", i, libusb_error_name(r)); return -1; }
} }
printf(" [OK] Step 1: Interfaces set and claimed.\n"); printf(" [OK] Interfaces set and claimed.\n");
printf("\n-- Step 2: Initial Handshake --\n");
CHECK("Status Check", libusb_control_transfer(handle, RT_D2H_VENDOR_DEV, VENDOR_REQ_MODE_CONTROL, 0x0000, 0x0000, buf, 1, USB_TIMEOUT)); CHECK("Status Check", libusb_control_transfer(handle, RT_D2H_VENDOR_DEV, VENDOR_REQ_MODE_CONTROL, 0x0000, 0x0000, buf, 1, USB_TIMEOUT));
printf("\n-- Step 3: Set Initial Mode --\n");
CHECK("Set Initial Mode", libusb_control_transfer(handle, RT_H2D_VENDOR_DEV, VENDOR_REQ_MODE_CONTROL, 0x0010, 0x0000, NULL, 0, USB_TIMEOUT)); CHECK("Set Initial Mode", libusb_control_transfer(handle, RT_H2D_VENDOR_DEV, VENDOR_REQ_MODE_CONTROL, 0x0010, 0x0000, NULL, 0, USB_TIMEOUT));
printf("\n-- Step 4: Set Sample Rate to %d Hz --\n", rate);
// We still set the capture rate, as the device expects it as part of the sequence.
CHECK("Set Rate on Capture EP (0x86)", libusb_control_transfer(handle, RT_H2D_CLASS_EP, UAC_SET_CUR, UAC_SAMPLING_FREQ_CONTROL, 0x86, rate_data, 3, USB_TIMEOUT)); CHECK("Set Rate on Capture EP (0x86)", libusb_control_transfer(handle, RT_H2D_CLASS_EP, UAC_SET_CUR, UAC_SAMPLING_FREQ_CONTROL, 0x86, rate_data, 3, USB_TIMEOUT));
CHECK("Set Rate on Playback EP (0x02)", libusb_control_transfer(handle, RT_H2D_CLASS_EP, UAC_SET_CUR, UAC_SAMPLING_FREQ_CONTROL, EP_AUDIO_OUT, rate_data, 3, USB_TIMEOUT)); CHECK("Set Rate on Playback EP (0x02)", libusb_control_transfer(handle, RT_H2D_CLASS_EP, UAC_SET_CUR, UAC_SAMPLING_FREQ_CONTROL, EP_AUDIO_OUT, rate_data, 3, USB_TIMEOUT));
printf("\n-- Step 5: Configure Internal Registers --\n");
CHECK("Reg Write 1 (0x0d04)", libusb_control_transfer(handle, RT_H2D_VENDOR_DEV, VENDOR_REQ_REGISTER_WRITE, 0x0d04, 0x0101, NULL, 0, USB_TIMEOUT)); CHECK("Reg Write 1 (0x0d04)", libusb_control_transfer(handle, RT_H2D_VENDOR_DEV, VENDOR_REQ_REGISTER_WRITE, 0x0d04, 0x0101, NULL, 0, USB_TIMEOUT));
CHECK("Reg Write 2 (0x0e00)", libusb_control_transfer(handle, RT_H2D_VENDOR_DEV, VENDOR_REQ_REGISTER_WRITE, 0x0e00, 0x0101, NULL, 0, USB_TIMEOUT)); CHECK("Reg Write 2 (0x0e00)", libusb_control_transfer(handle, RT_H2D_VENDOR_DEV, VENDOR_REQ_REGISTER_WRITE, 0x0e00, 0x0101, NULL, 0, USB_TIMEOUT));
CHECK("Reg Write 3 (0x0f00)", libusb_control_transfer(handle, RT_H2D_VENDOR_DEV, VENDOR_REQ_REGISTER_WRITE, 0x0f00, 0x0101, NULL, 0, USB_TIMEOUT)); CHECK("Reg Write 3 (0x0f00)", libusb_control_transfer(handle, RT_H2D_VENDOR_DEV, VENDOR_REQ_REGISTER_WRITE, 0x0f00, 0x0101, NULL, 0, USB_TIMEOUT));
CHECK("Reg Write 4 (Rate-Dep)", libusb_control_transfer(handle, RT_H2D_VENDOR_DEV, VENDOR_REQ_REGISTER_WRITE, rate_vendor_wValue, 0x0101, NULL, 0, USB_TIMEOUT)); CHECK("Reg Write 4 (Rate-Dep)", libusb_control_transfer(handle, RT_H2D_VENDOR_DEV, VENDOR_REQ_REGISTER_WRITE, rate_vendor_wValue, 0x0101, NULL, 0, USB_TIMEOUT));
CHECK("Reg Write 5 (0x110b)", libusb_control_transfer(handle, RT_H2D_VENDOR_DEV, VENDOR_REQ_REGISTER_WRITE, 0x110b, 0x0101, NULL, 0, USB_TIMEOUT)); CHECK("Reg Write 5 (0x110b)", libusb_control_transfer(handle, RT_H2D_VENDOR_DEV, VENDOR_REQ_REGISTER_WRITE, 0x110b, 0x0101, NULL, 0, USB_TIMEOUT));
printf("\n-- Step 6: Enable Streaming --\n");
CHECK("Enable Streaming", libusb_control_transfer(handle, RT_H2D_VENDOR_DEV, VENDOR_REQ_MODE_CONTROL, 0x0030, 0x0000, NULL, 0, USB_TIMEOUT)); CHECK("Enable Streaming", libusb_control_transfer(handle, RT_H2D_VENDOR_DEV, VENDOR_REQ_MODE_CONTROL, 0x0030, 0x0000, NULL, 0, USB_TIMEOUT));
printf("\n--- CONFIGURATION COMPLETE ---\n\n"); printf("\n--- CONFIGURATION COMPLETE ---\n\n");

BIN
src & scripts/tascam_streamer Normal file
View File

Binary file not shown.

741
src & scripts/us144mk2.c Normal file
View File

@ -0,0 +1,741 @@
// SPDX-License-Identifier: GPL-2.0
// (c) 2025 serifpersia <ramiserifpersia@gmail.com>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/delay.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
MODULE_AUTHOR("serifpersia");
MODULE_DESCRIPTION("ALSA Driver for TASCAM US-144MKII");
MODULE_LICENSE("GPL");
MODULE_VERSION("1.0");
#define DRIVER_NAME "us144mkii"
// --- Device and Endpoint Configuration ---
#define TASCAM_VID 0x0644
#define TASCAM_PID 0x8020
#define EP_AUDIO_OUT 0x02
#define EP_PLAYBACK_FEEDBACK 0x81
#define EP_CAPTURE_DATA 0x86
// --- USB Request Types ---
#define RT_H2D_CLASS_EP 0x22
#define RT_H2D_VENDOR_DEV 0x40
#define RT_D2H_VENDOR_DEV 0xc0
// --- UAC / Vendor Requests ---
#define UAC_SET_CUR 0x01
#define UAC_SAMPLING_FREQ_CONTROL 0x0100
#define VENDOR_REQ_REGISTER_WRITE 65
#define VENDOR_REQ_MODE_CONTROL 73
// --- Streaming Configuration ---
#define NUM_PLAYBACK_URBS 8
#define NUM_FEEDBACK_URBS 4
#define NUM_ISO_PACKETS 8
#define BYTES_PER_SAMPLE 3
#define DEVICE_CHANNELS 4
#define PLAYBACK_BYTES_PER_FRAME (DEVICE_CHANNELS * BYTES_PER_SAMPLE)
#define FEEDBACK_BYTES_PER_PACKET 3
#define MAX_SUPPORTED_RATE 96000
#define USB_CTRL_TIMEOUT_MS 1000
static struct usb_driver tascam_alsa_driver;
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;
int p_iso_packet_size;
struct urb *feedback_urbs[NUM_FEEDBACK_URBS];
size_t feedback_urb_alloc_size;
int f_iso_packet_size;
spinlock_t playback_lock;
atomic_t playback_active;
atomic_t feedback_active;
snd_pcm_uframes_t playback_pos;
};
// --- Forward Declarations ---
static int tascam_pcm_open(struct snd_pcm_substream *substream);
static int tascam_pcm_close(struct snd_pcm_substream *substream);
static int tascam_pcm_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params);
static int tascam_pcm_hw_free(struct snd_pcm_substream *substream);
static int tascam_pcm_prepare(struct snd_pcm_substream *substream);
static int tascam_pcm_trigger(struct snd_pcm_substream *substream, int cmd);
static snd_pcm_uframes_t tascam_pcm_pointer(struct snd_pcm_substream *substream);
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 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 = DEVICE_CHANNELS,
.channels_max = DEVICE_CHANNELS,
.buffer_bytes_max = 256 * 1024,
.period_bytes_min = 256,
.period_bytes_max = 64 * 1024,
.periods_min = 2,
.periods_max = 1024,
};
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 *substream) { return -ENODEV; }
static int tascam_capture_close_stub(struct snd_pcm_substream *substream) { return 0; }
static struct snd_pcm_ops tascam_capture_ops = {
.open = tascam_capture_open_stub,
.close = tascam_capture_close_stub,
};
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 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;
dev_info(&dev->dev, "Configuring device for rate %d Hz\n", rate);
rate_payload_buf = kmalloc(3, GFP_KERNEL);
if (!rate_payload_buf) return -ENOMEM;
switch (rate) {
case 44100: current_payload_src = payload_44100; rate_vendor_wValue = 0x1000; break;
case 48000: current_payload_src = payload_48000; rate_vendor_wValue = 0x1002; break;
case 88200: current_payload_src = payload_88200; rate_vendor_wValue = 0x1008; break;
case 96000: current_payload_src = payload_96000; rate_vendor_wValue = 0x100a; break;
default:
dev_err(&dev->dev, "Unsupported sample rate %d for configuration\n", rate);
kfree(rate_payload_buf);
return -EINVAL;
}
memcpy(rate_payload_buf, current_payload_src, 3);
err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), VENDOR_REQ_MODE_CONTROL, RT_H2D_VENDOR_DEV, 0x0010, 0x0000, NULL, 0, USB_CTRL_TIMEOUT_MS);
if (err < 0) { dev_err(&dev->dev, "Set Initial Mode (0x0010) failed: %d\n", err); goto cleanup_buf; }
err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR, RT_H2D_CLASS_EP, UAC_SAMPLING_FREQ_CONTROL, EP_CAPTURE_DATA, rate_payload_buf, 3, USB_CTRL_TIMEOUT_MS);
if (err < 0) { dev_err(&dev->dev, "Set Rate on Capture EP (0x%02x) failed: %d\n", EP_CAPTURE_DATA, err); goto cleanup_buf; }
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) { dev_err(&dev->dev, "Set Rate on Playback EP (0x%02x) failed: %d\n", EP_AUDIO_OUT, err); goto cleanup_buf; }
err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), VENDOR_REQ_REGISTER_WRITE, RT_H2D_VENDOR_DEV, 0x0d04, 0x0101, NULL, 0, USB_CTRL_TIMEOUT_MS);
if (err < 0) { dev_err(&dev->dev, "Reg Write 0x0d04 failed: %d\n", err); goto cleanup_buf; }
err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), VENDOR_REQ_REGISTER_WRITE, RT_H2D_VENDOR_DEV, 0x0e00, 0x0101, NULL, 0, USB_CTRL_TIMEOUT_MS);
if (err < 0) { dev_err(&dev->dev, "Reg Write 0x0e00 failed: %d\n", err); goto cleanup_buf; }
err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), VENDOR_REQ_REGISTER_WRITE, RT_H2D_VENDOR_DEV, 0x0f00, 0x0101, NULL, 0, USB_CTRL_TIMEOUT_MS);
if (err < 0) { dev_err(&dev->dev, "Reg Write 0x0f00 failed: %d\n", err); goto cleanup_buf; }
err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), VENDOR_REQ_REGISTER_WRITE, RT_H2D_VENDOR_DEV, rate_vendor_wValue, 0x0101, NULL, 0, USB_CTRL_TIMEOUT_MS);
if (err < 0) { dev_err(&dev->dev, "Rate-Dep Reg Write (0x%04x) failed: %d\n", rate_vendor_wValue, err); goto cleanup_buf; }
err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), VENDOR_REQ_REGISTER_WRITE, RT_H2D_VENDOR_DEV, 0x110b, 0x0101, NULL, 0, USB_CTRL_TIMEOUT_MS);
if (err < 0) { dev_err(&dev->dev, "Reg Write 0x110b failed: %d\n", err); goto cleanup_buf; }
err = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), VENDOR_REQ_MODE_CONTROL, RT_H2D_VENDOR_DEV, 0x0030, 0x0000, NULL, 0, USB_CTRL_TIMEOUT_MS);
if (err < 0) { dev_err(&dev->dev, "Enable Streaming (0x0030) failed: %d\n", err); goto cleanup_buf; }
dev_info(&dev->dev, "Device configuration for rate %d Hz completed.\n", rate);
cleanup_buf:
kfree(rate_payload_buf);
return err;
}
static int tascam_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
struct usb_device *dev = interface_to_usbdev(intf);
struct tascam_card *tascam;
struct snd_card *card;
struct snd_pcm *pcm;
int err;
u8 *handshake_buf;
if (intf->cur_altsetting->desc.bInterfaceNumber != 0)
return -ENODEV;
err = snd_card_new(&intf->dev, -1, "US144MKII", THIS_MODULE,
sizeof(struct tascam_card), &card);
if (err < 0) {
dev_err(&intf->dev, "Failed to create snd_card: %d\n", err);
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->playback_lock);
atomic_set(&tascam->playback_active, 0);
atomic_set(&tascam->feedback_active, 0);
strscpy(card->driver, DRIVER_NAME, sizeof(card->driver));
strscpy(card->shortname, "TASCAM US-144MKII", sizeof(card->shortname));
snprintf(card->longname, sizeof(card->longname), "%s (VID:%04X PID:%04X) at %s IF%d",
"TASCAM US-144MKII",
le16_to_cpu(dev->descriptor.idVendor),
le16_to_cpu(dev->descriptor.idProduct),
dev->bus->bus_name,
intf->cur_altsetting->desc.bInterfaceNumber);
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; }
dev_info(&intf->dev, "Interfaces 0 and 1 set to altsetting 1.\n");
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, 0x0000, 0x0000,
handshake_buf, 1, USB_CTRL_TIMEOUT_MS);
if (err < 0) {
dev_warn(&intf->dev, "Handshake read failed: %d (continuing)\n", err);
} else if (err == 1 && handshake_buf[0] == 0x12) {
dev_info(&intf->dev, "Handshake successful (response 0x12).\n");
} else {
dev_warn(&intf->dev, "Handshake: expected 0x12, got 0x%02x (len %d) (continuing)\n", handshake_buf[0], err);
}
kfree(handshake_buf);
handshake_buf = NULL;
err = us144mkii_configure_device_for_rate(tascam, 48000);
if (err < 0) {
dev_err(&intf->dev, "Initial device configuration for 48kHz failed: %d\n", err);
goto release_iface1_and_free_card;
}
err = snd_pcm_new(card, "US144MKII PCM", 0, 1, 1, &pcm);
if (err < 0) {
dev_err(&intf->dev, "Failed to create snd_pcm: %d\n", err);
goto release_iface1_and_free_card;
}
tascam->pcm = pcm;
snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &tascam_playback_ops);
snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &tascam_capture_ops);
pcm->private_data = tascam;
strscpy(pcm->name, "US-144MKII Audio", sizeof(pcm->name));
snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
usb_ifnum_to_if(dev,0)->dev.parent,
64 * 1024,
tascam_pcm_hw.buffer_bytes_max);
err = snd_card_register(card);
if (err < 0) {
dev_err(&intf->dev, "Failed to register snd_card: %d\n", err);
goto release_iface1_and_free_card;
}
dev_info(&intf->dev, "%s: TASCAM US-144MKII ALSA driver initialized.\n", card->longname);
return 0;
release_iface1_and_free_card:
if (tascam->iface1) {
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) {
dev_warn(&intf->dev, "Disconnect called on interface with no private data.\n");
return;
}
if (intf == tascam->iface0) {
dev_info(&intf->dev, "Disconnecting TASCAM US-144MKII (iface0)...\n");
atomic_set(&tascam->playback_active, 0);
atomic_set(&tascam->feedback_active, 0);
snd_card_disconnect(tascam->card);
if (tascam->iface1) {
dev_info(&intf->dev, "Releasing claimed interface 1.\n");
usb_driver_release_interface(&tascam_alsa_driver, tascam->iface1);
tascam->iface1 = NULL;
}
snd_card_free_when_closed(tascam->card);
dev_info(&intf->dev, "TASCAM US-144MKII (iface0) disconnected and scheduled for freeing.\n");
} else if (intf == tascam->iface1) {
dev_info(&intf->dev, "Disconnecting TASCAM US-144MKII (iface1). Data already cleared by iface0 disconnect.\n");
}
}
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;
int ret;
if (urb->status == -ENOENT || urb->status == -ECONNRESET || urb->status == -ESHUTDOWN) {
return;
}
if (!tascam || !atomic_read(&tascam->playback_active)) {
return;
}
substream = tascam->playback_substream;
if (!substream) return;
runtime = substream->runtime;
if (!runtime) return;
if (urb->status != 0) {
dev_warn_ratelimited(tascam->card->dev, "Playback URB completed with status %d\n", urb->status);
}
spin_lock_irqsave(&tascam->playback_lock, flags);
for (int i = 0; i < NUM_ISO_PACKETS; ++i) {
size_t dma_pos_bytes;
size_t current_iso_packet_len = tascam->p_iso_packet_size;
u8 *urb_packet_buffer = urb->transfer_buffer + (i * current_iso_packet_len);
dma_pos_bytes = frames_to_bytes(runtime, tascam->playback_pos);
if (dma_pos_bytes + current_iso_packet_len > runtime->dma_bytes) {
size_t len1 = runtime->dma_bytes - dma_pos_bytes;
memcpy(urb_packet_buffer, runtime->dma_area + dma_pos_bytes, len1);
memcpy(urb_packet_buffer + len1, runtime->dma_area, current_iso_packet_len - len1);
} else {
memcpy(urb_packet_buffer, runtime->dma_area + dma_pos_bytes, current_iso_packet_len);
}
tascam->playback_pos += bytes_to_frames(runtime, current_iso_packet_len);
if (tascam->playback_pos >= runtime->buffer_size) {
tascam->playback_pos -= runtime->buffer_size;
}
}
spin_unlock_irqrestore(&tascam->playback_lock, flags);
if (atomic_read(&tascam->playback_active)) {
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);
}
}
snd_pcm_period_elapsed(substream);
}
static void feedback_urb_complete(struct urb *urb)
{
struct tascam_card *tascam = urb->context;
int ret;
if (urb->status == -ENOENT || urb->status == -ECONNRESET || urb->status == -ESHUTDOWN) {
return;
}
if (!tascam || !atomic_read(&tascam->feedback_active)) {
return;
}
if (urb->status != 0) {
dev_warn_ratelimited(tascam->card->dev, "Feedback URB completed with status %d\n", urb->status);
}
if (atomic_read(&tascam->feedback_active)) {
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_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;
spin_lock_irqsave(&tascam->playback_lock, flags);
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_RESUME:
if (atomic_read(&tascam->playback_active)) {
err = -EBUSY;
break;
}
tascam->playback_pos = 0;
atomic_set(&tascam->playback_active, 1);
atomic_set(&tascam->feedback_active, 1);
dev_info(tascam->card->dev, "PCM TRIGGER START/RESUME\n");
break;
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_SUSPEND:
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
if (!atomic_read(&tascam->playback_active)) {
err = 0;
break;
}
atomic_set(&tascam->playback_active, 0);
atomic_set(&tascam->feedback_active, 0);
dev_info(tascam->card->dev, "PCM TRIGGER STOP/SUSPEND/PAUSE\n");
break;
default:
err = -EINVAL;
break;
}
spin_unlock_irqrestore(&tascam->playback_lock, flags);
if (err < 0) return err;
if (cmd == SNDRV_PCM_TRIGGER_START || cmd == SNDRV_PCM_TRIGGER_RESUME) {
for (i = 0; i < NUM_PLAYBACK_URBS; i++) {
err = usb_submit_urb(tascam->playback_urbs[i], GFP_ATOMIC);
if (err < 0) {
dev_err(tascam->card->dev, "Failed to submit playback URB %d: %d\n", i, err);
atomic_set(&tascam->playback_active, 0);
atomic_set(&tascam->feedback_active, 0);
for (int j = 0; j < i; j++) usb_kill_urb(tascam->playback_urbs[j]);
return err;
}
}
for (i = 0; i < NUM_FEEDBACK_URBS; i++) {
err = usb_submit_urb(tascam->feedback_urbs[i], GFP_ATOMIC);
if (err < 0) {
dev_err(tascam->card->dev, "Failed to submit feedback URB %d: %d\n", i, err);
atomic_set(&tascam->playback_active, 0);
atomic_set(&tascam->feedback_active, 0);
for (int j = 0; j < NUM_PLAYBACK_URBS; j++) usb_kill_urb(tascam->playback_urbs[j]);
for (int j = 0; j < i; j++) usb_kill_urb(tascam->feedback_urbs[j]);
return err;
}
}
} else if (cmd == SNDRV_PCM_TRIGGER_STOP || cmd == SNDRV_PCM_TRIGGER_SUSPEND || cmd == SNDRV_PCM_TRIGGER_PAUSE_PUSH) {
for (i = 0; i < NUM_PLAYBACK_URBS; i++)
if (tascam->playback_urbs[i]) usb_kill_urb(tascam->playback_urbs[i]);
for (i = 0; i < NUM_FEEDBACK_URBS; i++)
if (tascam->feedback_urbs[i]) usb_kill_urb(tascam->feedback_urbs[i]);
}
return 0;
}
static snd_pcm_uframes_t tascam_pcm_pointer(struct snd_pcm_substream *substream)
{
struct tascam_card *tascam = snd_pcm_substream_chip(substream);
return tascam->playback_pos;
}
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;
size_t total_urb_transfer_bytes;
size_t individual_iso_packet_size;
int i, j;
dev_info(tascam->card->dev, "PCM PREPARE: rate=%d, channels=%d, format=%d, period_size=%ld, periods=%d\n",
runtime->rate, runtime->channels, runtime->format, runtime->period_size, runtime->periods);
total_urb_transfer_bytes = (runtime->rate / 1000) * PLAYBACK_BYTES_PER_FRAME;
if (NUM_ISO_PACKETS == 0) {
dev_err(tascam->card->dev, "NUM_ISO_PACKETS is zero, invalid configuration.\n");
return -EINVAL;
}
individual_iso_packet_size = total_urb_transfer_bytes / NUM_ISO_PACKETS;
if (individual_iso_packet_size == 0 && total_urb_transfer_bytes > 0) {
dev_err(tascam->card->dev, "Zero individual ISO packet size. Rate %d, BPF %d, N_ISO %d\n",
runtime->rate, PLAYBACK_BYTES_PER_FRAME, NUM_ISO_PACKETS);
return -EINVAL;
}
tascam->p_iso_packet_size = individual_iso_packet_size;
for (i = 0; i < NUM_PLAYBACK_URBS; i++) {
struct urb *urb = tascam->playback_urbs[i];
if (!urb) continue;
if (total_urb_transfer_bytes > tascam->playback_urb_alloc_size) {
dev_err(tascam->card->dev, "Playback URB transfer size %zu > allocated %zu\n",
total_urb_transfer_bytes, tascam->playback_urb_alloc_size);
return -EINVAL;
}
memset(urb->transfer_buffer, 0, total_urb_transfer_bytes);
urb->transfer_buffer_length = total_urb_transfer_bytes;
urb->number_of_packets = NUM_ISO_PACKETS;
for (j = 0; j < NUM_ISO_PACKETS; j++) {
urb->iso_frame_desc[j].offset = j * tascam->p_iso_packet_size;
urb->iso_frame_desc[j].length = tascam->p_iso_packet_size;
}
}
tascam->f_iso_packet_size = FEEDBACK_BYTES_PER_PACKET;
for (i = 0; i < NUM_FEEDBACK_URBS; i++) {
struct urb *f_urb = tascam->feedback_urbs[i];
if (!f_urb) continue;
f_urb->transfer_buffer_length = tascam->f_iso_packet_size * NUM_ISO_PACKETS;
f_urb->number_of_packets = NUM_ISO_PACKETS;
for (j = 0; j < NUM_ISO_PACKETS; j++) {
f_urb->iso_frame_desc[j].offset = j * tascam->f_iso_packet_size;
f_urb->iso_frame_desc[j].length = tascam->f_iso_packet_size;
}
}
tascam->playback_pos = 0;
return 0;
}
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;
dev_info(tascam->card->dev, "PCM HW_PARAMS: rate=%u, channels=%u, format=%d, period_bytes=%u, periods=%u\n",
params_rate(params), params_channels(params), params_format(params),
params_period_bytes(params), params_periods(params));
if (params_channels(params) != DEVICE_CHANNELS) {
dev_warn(tascam->card->dev, "Requested %d channels, but device is fixed at %d. This may cause issues.\n",
params_channels(params), DEVICE_CHANNELS);
}
err = us144mkii_configure_device_for_rate(tascam, params_rate(params));
if (err < 0) {
dev_err(tascam->card->dev, "Failed to set hardware rate to %u: %d\n", params_rate(params), err);
return err;
}
return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
}
static int tascam_pcm_hw_free(struct snd_pcm_substream *substream)
{
return snd_pcm_lib_free_pages(substream);
}
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 i;
dev_info(tascam->card->dev, "PCM OPEN\n");
runtime->hw = tascam_pcm_hw;
tascam->playback_substream = substream;
atomic_set(&tascam->playback_active, 0);
atomic_set(&tascam->feedback_active, 0);
tascam->playback_urb_alloc_size = (MAX_SUPPORTED_RATE / 1000) * PLAYBACK_BYTES_PER_FRAME;
if (tascam->playback_urb_alloc_size == 0) {
dev_err(tascam->card->dev, "Calculated playback_urb_alloc_size is zero.\n");
return -EINVAL;
}
for (i = 0; i < NUM_PLAYBACK_URBS; i++) {
struct urb *urb = usb_alloc_urb(NUM_ISO_PACKETS, GFP_KERNEL);
if (!urb) goto error_free_playback_urbs;
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_free_playback_urbs;
}
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->f_iso_packet_size = FEEDBACK_BYTES_PER_PACKET;
tascam->feedback_urb_alloc_size = tascam->f_iso_packet_size * NUM_ISO_PACKETS;
if (tascam->feedback_urb_alloc_size == 0) {
dev_err(tascam->card->dev, "Calculated feedback_urb_alloc_size is zero.\n");
goto error_free_playback_urbs;
}
for (i = 0; i < NUM_FEEDBACK_URBS; i++) {
struct urb *f_urb = usb_alloc_urb(NUM_ISO_PACKETS, GFP_KERNEL);
if (!f_urb) goto error_free_feedback_urbs;
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_free_feedback_urbs;
}
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 = 1;
f_urb->context = tascam;
f_urb->complete = feedback_urb_complete;
}
return 0;
error_free_feedback_urbs:
for (i = 0; i < NUM_FEEDBACK_URBS; i++) {
if (tascam->feedback_urbs[i]) {
if (tascam->feedback_urbs[i]->transfer_buffer) {
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;
}
}
error_free_playback_urbs:
for (i = 0; i < NUM_PLAYBACK_URBS; i++) {
if (tascam->playback_urbs[i]) {
if (tascam->playback_urbs[i]->transfer_buffer) {
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;
}
}
return -ENOMEM;
}
static int tascam_pcm_close(struct snd_pcm_substream *substream)
{
struct tascam_card *tascam = snd_pcm_substream_chip(substream);
int i;
dev_info(tascam->card->dev, "PCM CLOSE\n");
atomic_set(&tascam->playback_active, 0);
atomic_set(&tascam->feedback_active, 0);
for (i = 0; i < NUM_PLAYBACK_URBS; i++) {
if (tascam->playback_urbs[i]) {
usb_kill_urb(tascam->playback_urbs[i]);
if (tascam->playback_urbs[i]->transfer_buffer) {
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]);
if (tascam->feedback_urbs[i]->transfer_buffer) {
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->playback_substream = NULL;
return 0;
}
// --- USB Driver Registration ---
static const struct usb_device_id tascam_id_table[] = {
{ USB_DEVICE(TASCAM_VID, TASCAM_PID) },
{ }
};
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,
};
module_usb_driver(tascam_alsa_driver);