// SPDX-License-Identifier: GPL-2.0+
/*
 * g_dnl.c -- USB Downloader Gadget
 *
 * Copyright (C) 2012 Samsung Electronics
 * Lukasz Majewski  <l.majewski@samsung.com>
 */

#include <common.h>
#include <malloc.h>

#include <mmc.h>
#include <part.h>
#include <usb.h>

#include <g_dnl.h>
#include <usb_mass_storage.h>
#include <dfu.h>
#include <thor.h>

#include <env_callback.h>

#include "gadget_chips.h"
#include "composite.c"

/*
 * One needs to define the following:
 * CONFIG_USB_GADGET_VENDOR_NUM
 * CONFIG_USB_GADGET_PRODUCT_NUM
 * CONFIG_USB_GADGET_MANUFACTURER
 * at e.g. ./configs/<board>_defconfig
 */

#define STRING_MANUFACTURER 25
#define STRING_PRODUCT 2
/* Index of String Descriptor describing this configuration */
#define STRING_USBDOWN 2
/* Index of String serial */
#define STRING_SERIAL  3
#define MAX_STRING_SERIAL       256
/* Number of supported configurations */
#define CONFIGURATION_NUMBER 1

#define DRIVER_VERSION          "usb_dnl 2.0"

static const char product[] = "USB download gadget";
static char g_dnl_serial[MAX_STRING_SERIAL];
static const char manufacturer[] = CONFIG_USB_GADGET_MANUFACTURER;

void g_dnl_set_serialnumber(char *s)
{
        memset(g_dnl_serial, 0, MAX_STRING_SERIAL);
        strncpy(g_dnl_serial, s, MAX_STRING_SERIAL - 1);
}

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

        .bcdUSB = __constant_cpu_to_le16(0x0200),
        .bDeviceClass = USB_CLASS_PER_INTERFACE,
        .bDeviceSubClass = 0, /*0x02:CDC-modem , 0x00:CDC-serial*/

        .idVendor = __constant_cpu_to_le16(CONFIG_USB_GADGET_VENDOR_NUM),
        .idProduct = __constant_cpu_to_le16(CONFIG_USB_GADGET_PRODUCT_NUM),
        /* .iProduct = DYNAMIC */
        /* .iSerialNumber = DYNAMIC */
        .bNumConfigurations = 1,
};

/*
 * static strings, in UTF-8
 * IDs for those strings are assigned dynamically at g_dnl_bind()
 */
static struct usb_string g_dnl_string_defs[] = {
        {.s = manufacturer},
        {.s = product},
        {.s = g_dnl_serial},
        { }             /* end of list */
};

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

static struct usb_gadget_strings *g_dnl_composite_strings[] = {
        &g_dnl_string_tab,
        NULL,
};

static int g_dnl_unbind(struct usb_composite_dev *cdev)
{
        struct usb_gadget *gadget = cdev->gadget;

        debug("%s: calling usb_gadget_disconnect for "
                        "controller '%s'\n", __func__, gadget->name);
        usb_gadget_disconnect(gadget);

        return 0;
}

static inline struct g_dnl_bind_callback *g_dnl_bind_callback_first(void)
{
        return ll_entry_start(struct g_dnl_bind_callback,
                                g_dnl_bind_callbacks);
}

static inline struct g_dnl_bind_callback *g_dnl_bind_callback_end(void)
{
        return ll_entry_end(struct g_dnl_bind_callback,
                                g_dnl_bind_callbacks);
}

static int g_dnl_do_config(struct usb_configuration *c)
{
        const char *s = c->cdev->driver->name;
        struct g_dnl_bind_callback *callback = g_dnl_bind_callback_first();

        debug("%s: configuration: 0x%p composite dev: 0x%p\n",
              __func__, c, c->cdev);

        for (; callback != g_dnl_bind_callback_end(); callback++)
                if (!strcmp(s, callback->usb_function_name))
                        return callback->fptr(c);
        return -ENODEV;
}

static int g_dnl_config_register(struct usb_composite_dev *cdev)
{
        struct usb_configuration *config;
        const char *name = "usb_dnload";

        config = memalign(CONFIG_SYS_CACHELINE_SIZE, sizeof(*config));
        if (!config)
                return -ENOMEM;

        memset(config, 0, sizeof(*config));

        config->label = name;
        config->bmAttributes = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER;
        config->bConfigurationValue = CONFIGURATION_NUMBER;
        config->iConfiguration = STRING_USBDOWN;
        config->bind = g_dnl_do_config;

        return usb_add_config(cdev, config);
}

__weak
int board_usb_init(int index, enum usb_init_type init)
{
        return 0;
}

__weak
int board_usb_cleanup(int index, enum usb_init_type init)
{
        return 0;
}

__weak
int g_dnl_bind_fixup(struct usb_device_descriptor *dev, const char *name)
{
        return 0;
}

__weak int g_dnl_get_board_bcd_device_number(int gcnum)
{
        return gcnum;
}

__weak int g_dnl_board_usb_cable_connected(void)
{
        return -EOPNOTSUPP;
}

static bool g_dnl_detach_request;

bool g_dnl_detach(void)
{
        return g_dnl_detach_request;
}

void g_dnl_trigger_detach(void)
{
        g_dnl_detach_request = true;
}

void g_dnl_clear_detach(void)
{
        g_dnl_detach_request = false;
}

static int g_dnl_get_bcd_device_number(struct usb_composite_dev *cdev)
{
        struct usb_gadget *gadget = cdev->gadget;
        int gcnum;

        gcnum = usb_gadget_controller_number(gadget);
        if (gcnum > 0)
                gcnum += 0x200;

        return g_dnl_get_board_bcd_device_number(gcnum);
}

/**
 * Update internal serial number variable when the "serial#" env var changes.
 *
 * Handle all cases, even when flags == H_PROGRAMMATIC or op == env_op_delete.
 */
static int on_serialno(const char *name, const char *value, enum env_op op,
                int flags)
{
        g_dnl_set_serialnumber((char *)value);
        return 0;
}
U_BOOT_ENV_CALLBACK(serialno, on_serialno);

static int g_dnl_bind(struct usb_composite_dev *cdev)
{
        struct usb_gadget *gadget = cdev->gadget;
        int id, ret;
        int gcnum;

        debug("%s: gadget: 0x%p cdev: 0x%p\n", __func__, gadget, cdev);

        id = usb_string_id(cdev);

        if (id < 0)
                return id;
        g_dnl_string_defs[0].id = id;
        device_desc.iManufacturer = id;

        id = usb_string_id(cdev);
        if (id < 0)
                return id;

        g_dnl_string_defs[1].id = id;
        device_desc.iProduct = id;

        g_dnl_bind_fixup(&device_desc, cdev->driver->name);

        if (strlen(g_dnl_serial)) {
                id = usb_string_id(cdev);
                if (id < 0)
                        return id;

                g_dnl_string_defs[2].id = id;
                device_desc.iSerialNumber = id;
        }

        ret = g_dnl_config_register(cdev);
        if (ret)
                goto error;

        gcnum = g_dnl_get_bcd_device_number(cdev);
        if (gcnum >= 0)
                device_desc.bcdDevice = cpu_to_le16(gcnum);
        else {
                debug("%s: controller '%s' not recognized\n",
                        __func__, gadget->name);
                device_desc.bcdDevice = __constant_cpu_to_le16(0x9999);
        }

        debug("%s: calling usb_gadget_connect for "
                        "controller '%s'\n", __func__, gadget->name);
        usb_gadget_connect(gadget);

        return 0;

 error:
        g_dnl_unbind(cdev);
        return -ENOMEM;
}

static struct usb_composite_driver g_dnl_driver = {
        .name = NULL,
        .dev = &device_desc,
        .strings = g_dnl_composite_strings,

        .bind = g_dnl_bind,
        .unbind = g_dnl_unbind,
};

/*
 * NOTICE:
 * Registering via USB function name won't be necessary after rewriting
 * g_dnl to support multiple USB functions.
 */
int g_dnl_register(const char *name)
{
        int ret;

        debug("%s: g_dnl_driver.name = %s\n", __func__, name);
        g_dnl_driver.name = name;

        ret = usb_composite_register(&g_dnl_driver);
        if (ret) {
                printf("%s: failed!, error: %d\n", __func__, ret);
                return ret;
        }
        return 0;
}

void g_dnl_unregister(void)
{
        usb_composite_unregister(&g_dnl_driver);
}