// SPDX-License-Identifier: GPL-2.0+
/*
 * audio.c -- Audio gadget driver
 *
 * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
 * Copyright (C) 2008 Analog Devices, Inc
 */

/* #define VERBOSE_DEBUG */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/usb/composite.h>

#define DRIVER_DESC             "Linux USB Audio Gadget"
#define DRIVER_VERSION          "Feb 2, 2012"

USB_GADGET_COMPOSITE_OPTIONS();

#ifndef CONFIG_GADGET_UAC1
#include "u_uac2.h"

/* Playback(USB-IN) Default Stereo - Fl/Fr */
static int p_chmask = UAC2_DEF_PCHMASK;
module_param(p_chmask, uint, 0444);
MODULE_PARM_DESC(p_chmask, "Playback Channel Mask");

/* Playback Default 48 KHz */
static int p_srates[UAC_MAX_RATES] = {UAC2_DEF_PSRATE};
static int p_srates_cnt = 1;
module_param_array_named(p_srate, p_srates, uint, &p_srates_cnt, 0444);
MODULE_PARM_DESC(p_srate, "Playback Sampling Rates (array)");

/* Playback Default 16bits/sample */
static int p_ssize = UAC2_DEF_PSSIZE;
module_param(p_ssize, uint, 0444);
MODULE_PARM_DESC(p_ssize, "Playback Sample Size(bytes)");

/* Playback bInterval for HS/SS (1-4: fixed, 0: auto) */
static u8 p_hs_bint = UAC2_DEF_PHSBINT;
module_param(p_hs_bint, byte, 0444);
MODULE_PARM_DESC(p_hs_bint,
                "Playback bInterval for HS/SS (1-4: fixed, 0: auto)");

/* Capture(USB-OUT) Default Stereo - Fl/Fr */
static int c_chmask = UAC2_DEF_CCHMASK;
module_param(c_chmask, uint, 0444);
MODULE_PARM_DESC(c_chmask, "Capture Channel Mask");

/* Capture Default 64 KHz */
static int c_srates[UAC_MAX_RATES] = {UAC2_DEF_CSRATE};
static int c_srates_cnt = 1;
module_param_array_named(c_srate, c_srates, uint, &c_srates_cnt, 0444);
MODULE_PARM_DESC(c_srate, "Capture Sampling Rates (array)");

/* Capture Default 16bits/sample */
static int c_ssize = UAC2_DEF_CSSIZE;
module_param(c_ssize, uint, 0444);
MODULE_PARM_DESC(c_ssize, "Capture Sample Size(bytes)");

/* capture bInterval for HS/SS (1-4: fixed, 0: auto) */
static u8 c_hs_bint = UAC2_DEF_CHSBINT;
module_param(c_hs_bint, byte, 0444);
MODULE_PARM_DESC(c_hs_bint,
                "Capture bInterval for HS/SS (1-4: fixed, 0: auto)");

#else
#ifndef CONFIG_GADGET_UAC1_LEGACY
#include "u_uac1.h"

/* Playback(USB-IN) Default Stereo - Fl/Fr */
static int p_chmask = UAC1_DEF_PCHMASK;
module_param(p_chmask, uint, 0444);
MODULE_PARM_DESC(p_chmask, "Playback Channel Mask");

/* Playback Default 48 KHz */
static int p_srates[UAC_MAX_RATES] = {UAC1_DEF_PSRATE};
static int p_srates_cnt = 1;
module_param_array_named(p_srate, p_srates, uint, &p_srates_cnt, 0444);
MODULE_PARM_DESC(p_srate, "Playback Sampling Rates (array)");

/* Playback Default 16bits/sample */
static int p_ssize = UAC1_DEF_PSSIZE;
module_param(p_ssize, uint, 0444);
MODULE_PARM_DESC(p_ssize, "Playback Sample Size(bytes)");

/* Capture(USB-OUT) Default Stereo - Fl/Fr */
static int c_chmask = UAC1_DEF_CCHMASK;
module_param(c_chmask, uint, 0444);
MODULE_PARM_DESC(c_chmask, "Capture Channel Mask");

/* Capture Default 48 KHz */
static int c_srates[UAC_MAX_RATES] = {UAC1_DEF_CSRATE};
static int c_srates_cnt = 1;
module_param_array_named(c_srate, c_srates, uint, &c_srates_cnt, 0444);
MODULE_PARM_DESC(c_srate, "Capture Sampling Rates (array)");

/* Capture Default 16bits/sample */
static int c_ssize = UAC1_DEF_CSSIZE;
module_param(c_ssize, uint, 0444);
MODULE_PARM_DESC(c_ssize, "Capture Sample Size(bytes)");
#else /* CONFIG_GADGET_UAC1_LEGACY */
#include "u_uac1_legacy.h"

static char *fn_play = FILE_PCM_PLAYBACK;
module_param(fn_play, charp, 0444);
MODULE_PARM_DESC(fn_play, "Playback PCM device file name");

static char *fn_cap = FILE_PCM_CAPTURE;
module_param(fn_cap, charp, 0444);
MODULE_PARM_DESC(fn_cap, "Capture PCM device file name");

static char *fn_cntl = FILE_CONTROL;
module_param(fn_cntl, charp, 0444);
MODULE_PARM_DESC(fn_cntl, "Control device file name");

static int req_buf_size = UAC1_OUT_EP_MAX_PACKET_SIZE;
module_param(req_buf_size, int, 0444);
MODULE_PARM_DESC(req_buf_size, "ISO OUT endpoint request buffer size");

static int req_count = UAC1_REQ_COUNT;
module_param(req_count, int, 0444);
MODULE_PARM_DESC(req_count, "ISO OUT endpoint request count");

static int audio_buf_size = UAC1_AUDIO_BUF_SIZE;
module_param(audio_buf_size, int, 0444);
MODULE_PARM_DESC(audio_buf_size, "Audio buffer size");
#endif /* CONFIG_GADGET_UAC1_LEGACY */
#endif

/* string IDs are assigned dynamically */

static struct usb_string strings_dev[] = {
        [USB_GADGET_MANUFACTURER_IDX].s = "",
        [USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
        [USB_GADGET_SERIAL_IDX].s = "",
        {  } /* end of list */
};

static struct usb_gadget_strings stringtab_dev = {
        .language = 0x0409,     /* en-us */
        .strings = strings_dev,
};

static struct usb_gadget_strings *audio_strings[] = {
        &stringtab_dev,
        NULL,
};

#ifndef CONFIG_GADGET_UAC1
static struct usb_function_instance *fi_uac2;
static struct usb_function *f_uac2;
#else
static struct usb_function_instance *fi_uac1;
static struct usb_function *f_uac1;
#endif

/*-------------------------------------------------------------------------*/

/* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
 * Instead:  allocate your own, using normal USB-IF procedures.
 */

/* Thanks to Linux Foundation for donating this product ID. */
#define AUDIO_VENDOR_NUM                0x1d6b  /* Linux Foundation */
#define AUDIO_PRODUCT_NUM               0x0101  /* Linux-USB Audio Gadget */

/*-------------------------------------------------------------------------*/

static struct usb_device_descriptor device_desc = {
        .bLength =              sizeof device_desc,
        .bDescriptorType =      USB_DT_DEVICE,

        /* .bcdUSB = DYNAMIC */

#ifdef CONFIG_GADGET_UAC1_LEGACY
        .bDeviceClass =         USB_CLASS_PER_INTERFACE,
        .bDeviceSubClass =      0,
        .bDeviceProtocol =      0,
#else
        .bDeviceClass =         USB_CLASS_MISC,
        .bDeviceSubClass =      0x02,
        .bDeviceProtocol =      0x01,
#endif
        /* .bMaxPacketSize0 = f(hardware) */

        /* Vendor and product id defaults change according to what configs
         * we support.  (As does bNumConfigurations.)  These values can
         * also be overridden by module parameters.
         */
        .idVendor =             cpu_to_le16(AUDIO_VENDOR_NUM),
        .idProduct =            cpu_to_le16(AUDIO_PRODUCT_NUM),
        /* .bcdDevice = f(hardware) */
        /* .iManufacturer = DYNAMIC */
        /* .iProduct = DYNAMIC */
        /* NO SERIAL NUMBER */
        .bNumConfigurations =   1,
};

static const struct usb_descriptor_header *otg_desc[2];

/*-------------------------------------------------------------------------*/

static int audio_do_config(struct usb_configuration *c)
{
        int status;

        /* FIXME alloc iConfiguration string, set it in c->strings */

        if (gadget_is_otg(c->cdev->gadget)) {
                c->descriptors = otg_desc;
                c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
        }

#ifdef CONFIG_GADGET_UAC1
        f_uac1 = usb_get_function(fi_uac1);
        if (IS_ERR(f_uac1)) {
                status = PTR_ERR(f_uac1);
                return status;
        }

        status = usb_add_function(c, f_uac1);
        if (status < 0) {
                usb_put_function(f_uac1);
                return status;
        }
#else
        f_uac2 = usb_get_function(fi_uac2);
        if (IS_ERR(f_uac2)) {
                status = PTR_ERR(f_uac2);
                return status;
        }

        status = usb_add_function(c, f_uac2);
        if (status < 0) {
                usb_put_function(f_uac2);
                return status;
        }
#endif

        return 0;
}

static struct usb_configuration audio_config_driver = {
        .label                  = DRIVER_DESC,
        .bConfigurationValue    = 1,
        /* .iConfiguration = DYNAMIC */
        .bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
};

/*-------------------------------------------------------------------------*/

static int audio_bind(struct usb_composite_dev *cdev)
{
#ifndef CONFIG_GADGET_UAC1
        struct f_uac2_opts      *uac2_opts;
        int i;
#else
#ifndef CONFIG_GADGET_UAC1_LEGACY
        struct f_uac1_opts      *uac1_opts;
        int i;
#else
        struct f_uac1_legacy_opts       *uac1_opts;
#endif
#endif
        int                     status;

#ifndef CONFIG_GADGET_UAC1
        fi_uac2 = usb_get_function_instance("uac2");
        if (IS_ERR(fi_uac2))
                return PTR_ERR(fi_uac2);
#else
#ifndef CONFIG_GADGET_UAC1_LEGACY
        fi_uac1 = usb_get_function_instance("uac1");
#else
        fi_uac1 = usb_get_function_instance("uac1_legacy");
#endif
        if (IS_ERR(fi_uac1))
                return PTR_ERR(fi_uac1);
#endif

#ifndef CONFIG_GADGET_UAC1
        uac2_opts = container_of(fi_uac2, struct f_uac2_opts, func_inst);
        uac2_opts->p_chmask = p_chmask;

        for (i = 0; i < p_srates_cnt; ++i)
                uac2_opts->p_srates[i] = p_srates[i];

        uac2_opts->p_ssize = p_ssize;
        uac2_opts->p_hs_bint = p_hs_bint;
        uac2_opts->c_chmask = c_chmask;

        for (i = 0; i < c_srates_cnt; ++i)
                uac2_opts->c_srates[i] = c_srates[i];

        uac2_opts->c_ssize = c_ssize;
        uac2_opts->c_hs_bint = c_hs_bint;
        uac2_opts->req_number = UAC2_DEF_REQ_NUM;
#else
#ifndef CONFIG_GADGET_UAC1_LEGACY
        uac1_opts = container_of(fi_uac1, struct f_uac1_opts, func_inst);
        uac1_opts->p_chmask = p_chmask;

        for (i = 0; i < p_srates_cnt; ++i)
                uac1_opts->p_srates[i] = p_srates[i];

        uac1_opts->p_ssize = p_ssize;
        uac1_opts->c_chmask = c_chmask;

        for (i = 0; i < c_srates_cnt; ++i)
                uac1_opts->c_srates[i] = c_srates[i];

        uac1_opts->c_ssize = c_ssize;
        uac1_opts->req_number = UAC1_DEF_REQ_NUM;
#else /* CONFIG_GADGET_UAC1_LEGACY */
        uac1_opts = container_of(fi_uac1, struct f_uac1_legacy_opts, func_inst);
        uac1_opts->fn_play = fn_play;
        uac1_opts->fn_cap = fn_cap;
        uac1_opts->fn_cntl = fn_cntl;
        uac1_opts->req_buf_size = req_buf_size;
        uac1_opts->req_count = req_count;
        uac1_opts->audio_buf_size = audio_buf_size;
#endif /* CONFIG_GADGET_UAC1_LEGACY */
#endif

        status = usb_string_ids_tab(cdev, strings_dev);
        if (status < 0)
                goto fail;
        device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
        device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;

        if (gadget_is_otg(cdev->gadget) && !otg_desc[0]) {
                struct usb_descriptor_header *usb_desc;

                usb_desc = usb_otg_descriptor_alloc(cdev->gadget);
                if (!usb_desc) {
                        status = -ENOMEM;
                        goto fail;
                }
                usb_otg_descriptor_init(cdev->gadget, usb_desc);
                otg_desc[0] = usb_desc;
                otg_desc[1] = NULL;
        }

        status = usb_add_config(cdev, &audio_config_driver, audio_do_config);
        if (status < 0)
                goto fail_otg_desc;
        usb_composite_overwrite_options(cdev, &coverwrite);

        INFO(cdev, "%s, version: %s\n", DRIVER_DESC, DRIVER_VERSION);
        return 0;

fail_otg_desc:
        kfree(otg_desc[0]);
        otg_desc[0] = NULL;
fail:
#ifndef CONFIG_GADGET_UAC1
        usb_put_function_instance(fi_uac2);
#else
        usb_put_function_instance(fi_uac1);
#endif
        return status;
}

static int audio_unbind(struct usb_composite_dev *cdev)
{
#ifdef CONFIG_GADGET_UAC1
        if (!IS_ERR_OR_NULL(f_uac1))
                usb_put_function(f_uac1);
        if (!IS_ERR_OR_NULL(fi_uac1))
                usb_put_function_instance(fi_uac1);
#else
        if (!IS_ERR_OR_NULL(f_uac2))
                usb_put_function(f_uac2);
        if (!IS_ERR_OR_NULL(fi_uac2))
                usb_put_function_instance(fi_uac2);
#endif
        kfree(otg_desc[0]);
        otg_desc[0] = NULL;

        return 0;
}

static struct usb_composite_driver audio_driver = {
        .name           = "g_audio",
        .dev            = &device_desc,
        .strings        = audio_strings,
        .max_speed      = USB_SPEED_HIGH,
        .bind           = audio_bind,
        .unbind         = audio_unbind,
};

module_usb_composite_driver(audio_driver);

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("Bryan Wu <cooloney@kernel.org>");
MODULE_LICENSE("GPL");