us144mkii/us144mkii.h

226 lines
7.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
// Copyright (c) 2025 Šerif Rami <ramiserifpersia@gmail.com>
#ifndef __US144MKII_H
#define __US144MKII_H
#include <linux/usb.h>
#include <linux/workqueue.h>
#include <sound/core.h>
#include <sound/initval.h>
#include <sound/pcm.h>
#define DRIVER_NAME "us144mkii"
/* --- USB Device Identification --- */
#define USB_VID_TASCAM 0x0644
#define USB_PID_TASCAM_US144 0x800f
#define USB_PID_TASCAM_US144MKII 0x8020
/* --- USB Endpoints (Alternate Setting 1) --- */
#define EP_PLAYBACK_FEEDBACK 0x81
#define EP_AUDIO_OUT 0x02
/* --- USB Control Message Protocol --- */
#define RT_H2D_CLASS_EP (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT)
#define RT_D2H_VENDOR_DEV (USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE)
#define RT_H2D_VENDOR_DEV (USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE)
enum uac_request {
UAC_SET_CUR = 0x01,
};
enum uac_control_selector {
UAC_SAMPLING_FREQ_CONTROL = 0x0100,
};
enum tascam_vendor_request {
VENDOR_REQ_REGISTER_WRITE = 0x41,
VENDOR_REQ_MODE_CONTROL = 0x49,
};
enum tascam_mode_value {
MODE_VAL_HANDSHAKE_READ = 0x0000,
MODE_VAL_CONFIG = 0x0010,
MODE_VAL_STREAM_START = 0x0030,
};
enum tascam_register {
REG_ADDR_UNKNOWN_0D = 0x0d04,
REG_ADDR_UNKNOWN_0E = 0x0e00,
REG_ADDR_UNKNOWN_0F = 0x0f00,
REG_ADDR_RATE_44100 = 0x1000,
REG_ADDR_RATE_48000 = 0x1002,
REG_ADDR_RATE_88200 = 0x1008,
REG_ADDR_RATE_96000 = 0x100a,
REG_ADDR_UNKNOWN_11 = 0x110b,
};
#define REG_VAL_ENABLE 0x0101
/* --- URB Configuration --- */
#define NUM_PLAYBACK_URBS 4
#define PLAYBACK_URB_PACKETS 8
#define NUM_FEEDBACK_URBS 4
#define FEEDBACK_URB_PACKETS 1
#define FEEDBACK_PACKET_SIZE 3
#define USB_CTRL_TIMEOUT_MS 1000
#define FEEDBACK_SYNC_LOSS_THRESHOLD 41
/* --- 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
struct tascam_card;
#include "us144mkii_pcm.h"
/**
* struct us144mkii_frame_pattern_observer - State for dynamic feedback
* patterns.
* @sample_rate_khz: The current sample rate in kHz.
* @base_feedback_value: The nominal feedback value for the current rate.
* @feedback_offset: An offset to align the feedback value range.
* @full_frame_patterns: A 2D array of pre-calculated packet size patterns.
* @current_index: The current index into the pattern array.
* @previous_index: The previous index, used for state tracking.
* @sync_locked: A flag indicating if the pattern has locked to the stream.
*/
struct us144mkii_frame_pattern_observer {
unsigned int sample_rate_khz;
unsigned int base_feedback_value;
int feedback_offset;
unsigned int full_frame_patterns[5][8];
unsigned int current_index;
unsigned int previous_index;
bool sync_locked;
};
/**
* struct tascam_card - Main driver data structure for the TASCAM US-144MKII.
* @dev: Pointer to the USB device.
* @iface0: Pointer to USB interface 0 (audio).
* @iface1: Pointer to USB interface 1 (MIDI).
* @card: Pointer to the ALSA sound card instance.
* @pcm: Pointer to the ALSA PCM device.
*
* @playback_substream: Pointer to the active playback PCM substream.
* @playback_urbs: Array of URBs for playback.
* @playback_urb_alloc_size: Size of allocated buffer for each playback URB.
* @feedback_urbs: Array of URBs for feedback.
* @feedback_urb_alloc_size: Size of allocated buffer for each feedback URB.
* @playback_active: Atomic flag indicating if playback is active.
* @playback_frames_consumed: Total frames consumed by playback.
* @driver_playback_pos: Current position in the ALSA playback buffer (frames).
* @last_period_pos: Last reported period position for playback.
*
* @capture_substream: Pointer to the active capture PCM substream.
* @capture_active: Atomic flag indicating if capture is active.
* @driver_capture_pos: Current position in the ALSA capture buffer (frames).
* @capture_frames_processed: Total frames processed for capture.
* @last_capture_period_pos: Last reported period position for capture.
*
* @stop_work: Work struct for deferred stream stopping.
* @stop_pcm_work: Work struct for stopping PCM due to a fatal error (e.g.
* xrun).
*
* @lock: Main spinlock for protecting shared driver state.
* @active_urbs: Atomic counter for active URBs.
* @current_rate: Currently configured sample rate of the device.
*
* @feedback_accumulator_pattern: Stores the calculated frames per packet for
* feedback.
* @feedback_pattern_out_idx: Read index for feedback_accumulator_pattern.
* @feedback_pattern_in_idx: Write index for feedback_accumulator_pattern.
* @feedback_synced: Flag indicating if feedback is synced.
* @feedback_consecutive_errors: Counter for consecutive feedback errors.
* @feedback_urb_skip_count: Number of feedback URBs to skip initially for
* stabilization.
* @fpo: Holds the state for the dynamic feedback pattern generation.
*
* @playback_anchor: USB anchor for playback URBs.
* @feedback_anchor: USB anchor for feedback URBs.
*/
struct tascam_card {
/* --- Core device pointers --- */
struct usb_device *dev;
struct usb_interface *iface0;
struct usb_interface *iface1;
struct snd_card *card;
struct snd_pcm *pcm;
/* --- PCM Substreams --- */
struct snd_pcm_substream *playback_substream;
struct snd_pcm_substream *capture_substream;
/* --- URBs and Anchors --- */
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;
struct usb_anchor playback_anchor;
struct usb_anchor feedback_anchor;
/* --- Stream State --- */
spinlock_t lock;
atomic_t playback_active;
atomic_t capture_active;
atomic_t active_urbs;
int current_rate;
/* --- Playback State --- */
u64 playback_frames_consumed;
snd_pcm_uframes_t driver_playback_pos;
u64 last_period_pos;
/* --- Capture State --- */
u64 capture_frames_processed;
snd_pcm_uframes_t driver_capture_pos;
u64 last_capture_period_pos;
/* --- Feedback Sync State --- */
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;
struct us144mkii_frame_pattern_observer fpo;
/* --- Workqueues --- */
struct work_struct stop_work;
struct work_struct stop_pcm_work;
};
/**
* tascam_free_urbs() - Free all allocated URBs and associated buffers.
* @tascam: the tascam_card instance
*
* This function kills, unlinks, and frees all playback and feedback URBs,
* along with their transfer buffers.
*/
void tascam_free_urbs(struct tascam_card *tascam);
/**
* tascam_alloc_urbs() - Allocate all URBs and associated buffers.
* @tascam: the tascam_card instance
*
* This function allocates and initializes all URBs for playback and feedback.
*
* Return: 0 on success, or a negative error code on failure.
*/
int tascam_alloc_urbs(struct tascam_card *tascam);
/**
* tascam_stop_work_handler() - Work handler to stop all active streams.
* @work: Pointer to the work_struct.
*
* This function is scheduled to stop all active URBs (playback, feedback)
* and reset the active_urbs counter.
*/
void tascam_stop_work_handler(struct work_struct *work);
#endif /* __US144MKII_H */