/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Line 6 Linux USB driver
 *
 * Copyright (C) 2004-2010 Markus Grabner (line6@grabner-graz.at)
 */

#ifndef DRIVER_H
#define DRIVER_H

#include <linux/usb.h>
#include <linux/mutex.h>
#include <linux/kfifo.h>
#include <sound/core.h>

#include "midi.h"

/* USB 1.1 speed configuration */
#define USB_LOW_INTERVALS_PER_SECOND 1000
#define USB_LOW_ISO_BUFFERS 2

/* USB 2.0+ speed configuration */
#define USB_HIGH_INTERVALS_PER_SECOND 8000
#define USB_HIGH_ISO_BUFFERS 16

/* Fallback USB interval and max packet size values */
#define LINE6_FALLBACK_INTERVAL 10
#define LINE6_FALLBACK_MAXPACKETSIZE 16

#define LINE6_TIMEOUT 1000
#define LINE6_BUFSIZE_LISTEN 64
#define LINE6_MIDI_MESSAGE_MAXLEN 256

#define LINE6_RAW_MESSAGES_MAXCOUNT_ORDER 7
/* 4k packets are common, BUFSIZE * MAXCOUNT should be bigger... */
#define LINE6_RAW_MESSAGES_MAXCOUNT (1 << LINE6_RAW_MESSAGES_MAXCOUNT_ORDER)


#if LINE6_BUFSIZE_LISTEN > 65535
#error "Use dynamic fifo instead"
#endif

/*
        Line 6 MIDI control commands
*/
#define LINE6_PARAM_CHANGE   0xb0
#define LINE6_PROGRAM_CHANGE 0xc0
#define LINE6_SYSEX_BEGIN    0xf0
#define LINE6_SYSEX_END      0xf7
#define LINE6_RESET          0xff

/*
        MIDI channel for messages initiated by the host
        (and eventually echoed back by the device)
*/
#define LINE6_CHANNEL_HOST   0x00

/*
        MIDI channel for messages initiated by the device
*/
#define LINE6_CHANNEL_DEVICE 0x02

#define LINE6_CHANNEL_UNKNOWN 5 /* don't know yet what this is good for */

#define LINE6_CHANNEL_MASK 0x0f

extern const unsigned char line6_midi_id[3];

#define SYSEX_DATA_OFS (sizeof(line6_midi_id) + 3)
#define SYSEX_EXTRA_SIZE (sizeof(line6_midi_id) + 4)

/*
         Common properties of Line 6 devices.
*/
struct line6_properties {
        /* Card id string (maximum 16 characters).
         * This can be used to address the device in ALSA programs as
         * "default:CARD=<id>"
         */
        const char *id;

        /* Card short name (maximum 32 characters) */
        const char *name;

        /* Bit vector defining this device's capabilities in line6usb driver */
        int capabilities;

        int altsetting;

        unsigned int ctrl_if;
        unsigned int ep_ctrl_r;
        unsigned int ep_ctrl_w;
        unsigned int ep_audio_r;
        unsigned int ep_audio_w;
};

/* Capability bits */
enum {
        /* device supports settings parameter via USB */
        LINE6_CAP_CONTROL =     1 << 0,
        /* device supports PCM input/output via USB */
        LINE6_CAP_PCM =         1 << 1,
        /* device supports hardware monitoring */
        LINE6_CAP_HWMON =       1 << 2,
        /* device requires output data when input is read */
        LINE6_CAP_IN_NEEDS_OUT = 1 << 3,
        /* device uses raw MIDI via USB (data endpoints) */
        LINE6_CAP_CONTROL_MIDI = 1 << 4,
        /* device provides low-level information */
        LINE6_CAP_CONTROL_INFO = 1 << 5,
        /* device provides hardware monitoring volume control */
        LINE6_CAP_HWMON_CTL =   1 << 6,
};

/*
         Common data shared by all Line 6 devices.
         Corresponds to a pair of USB endpoints.
*/
struct usb_line6 {
        /* USB device */
        struct usb_device *usbdev;

        /* Properties */
        const struct line6_properties *properties;

        /* Interval for data USB packets */
        int interval;
        /* ...for isochronous transfers framing */
        int intervals_per_second;

        /* Number of isochronous URBs used for frame transfers */
        int iso_buffers;

        /* Maximum size of data USB packet */
        int max_packet_size;

        /* Device representing the USB interface */
        struct device *ifcdev;

        /* Line 6 sound card data structure.
         * Each device has at least MIDI or PCM.
         */
        struct snd_card *card;

        /* Line 6 PCM device data structure */
        struct snd_line6_pcm *line6pcm;

        /* Line 6 MIDI device data structure */
        struct snd_line6_midi *line6midi;

        /* URB for listening to POD data endpoint */
        struct urb *urb_listen;

        /* Buffer for incoming data from POD data endpoint */
        unsigned char *buffer_listen;

        /* Buffer for message to be processed, generated from MIDI layer */
        unsigned char *buffer_message;

        /* Length of message to be processed, generated from MIDI layer  */
        int message_length;

        /* Circular buffer for non-MIDI control messages */
        struct {
                struct mutex read_lock;
                wait_queue_head_t wait_queue;
                unsigned int active:1;
                unsigned int nonblock:1;
                STRUCT_KFIFO_REC_2(LINE6_BUFSIZE_LISTEN * LINE6_RAW_MESSAGES_MAXCOUNT)
                        fifo;
        } messages;

        /* Work for delayed PCM startup */
        struct delayed_work startup_work;

        /* If MIDI is supported, buffer_message contains the pre-processed data;
         * otherwise the data is only in urb_listen (buffer_incoming).
         */
        void (*process_message)(struct usb_line6 *);
        void (*disconnect)(struct usb_line6 *line6);
        void (*startup)(struct usb_line6 *line6);
};

extern char *line6_alloc_sysex_buffer(struct usb_line6 *line6, int code1,
                                      int code2, int size);
extern int line6_read_data(struct usb_line6 *line6, unsigned address,
                           void *data, unsigned datalen);
extern int line6_read_serial_number(struct usb_line6 *line6,
                                    u32 *serial_number);
extern int line6_send_raw_message(struct usb_line6 *line6,
                                        const char *buffer, int size);
extern int line6_send_raw_message_async(struct usb_line6 *line6,
                                        const char *buffer, int size);
extern int line6_send_sysex_message(struct usb_line6 *line6,
                                    const char *buffer, int size);
extern int line6_version_request_async(struct usb_line6 *line6);
extern int line6_write_data(struct usb_line6 *line6, unsigned address,
                            void *data, unsigned datalen);

int line6_probe(struct usb_interface *interface,
                const struct usb_device_id *id,
                const char *driver_name,
                const struct line6_properties *properties,
                int (*private_init)(struct usb_line6 *, const struct usb_device_id *id),
                size_t data_size);

void line6_disconnect(struct usb_interface *interface);

#ifdef CONFIG_PM
int line6_suspend(struct usb_interface *interface, pm_message_t message);
int line6_resume(struct usb_interface *interface);
#endif

#endif