/*
 * acm_ms.c -- Composite driver, with ACM and mass storage support
 *
 * Copyright (C) 2008 David Brownell
 * Copyright (C) 2008 Nokia Corporation
 * Author: David Brownell
 * Modified: Klaus Schwarzkopf <schwarzkopf@sensortherm.de>
 *
 * Heavily based on multi.c and cdc2.c
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

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

#include "u_serial.h"

#define DRIVER_DESC		"Composite Gadget (ACM + MS)"
#define DRIVER_VERSION		"2011/10/10"

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

/*
 * DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
 * Instead:  allocate your own, using normal USB-IF procedures.
 */
#define ACM_MS_VENDOR_NUM	0x1d6b	/* Linux Foundation */
#define ACM_MS_PRODUCT_NUM	0x0106	/* Composite Gadget: ACM + MS*/

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

/*
 * Kbuild is not very cooperative with respect to linking separately
 * compiled library objects into one module.  So for now we won't use
 * separate compilation ... ensuring init/exit sections work to shrink
 * the runtime footprint, and giving us at least some parts of what
 * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
 */
#include "f_mass_storage.c"

/*-------------------------------------------------------------------------*/
USB_GADGET_COMPOSITE_OPTIONS();

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

	.bcdUSB =		cpu_to_le16(0x0200),

	.bDeviceClass =		USB_CLASS_MISC /* 0xEF */,
	.bDeviceSubClass =	2,
	.bDeviceProtocol =	1,

	/* .bMaxPacketSize0 = f(hardware) */

	/* Vendor and product id can be overridden by module parameters.  */
	.idVendor =		cpu_to_le16(ACM_MS_VENDOR_NUM),
	.idProduct =		cpu_to_le16(ACM_MS_PRODUCT_NUM),
	/* .bcdDevice = f(hardware) */
	/* .iManufacturer = DYNAMIC */
	/* .iProduct = DYNAMIC */
	/* NO SERIAL NUMBER */
	/*.bNumConfigurations =	DYNAMIC*/
};

static struct usb_otg_descriptor otg_descriptor = {
	.bLength =		sizeof otg_descriptor,
	.bDescriptorType =	USB_DT_OTG,

	/*
	 * REVISIT SRP-only hardware is possible, although
	 * it would not be called "OTG" ...
	 */
	.bmAttributes =		USB_OTG_SRP | USB_OTG_HNP,
};

static const struct usb_descriptor_header *otg_desc[] = {
	(struct usb_descriptor_header *) &otg_descriptor,
	NULL,
};

/* 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 *dev_strings[] = {
	&stringtab_dev,
	NULL,
};

/****************************** Configurations ******************************/

static struct fsg_module_parameters fsg_mod_data = { .stall = 1 };
FSG_MODULE_PARAMETERS(/* no prefix */, fsg_mod_data);

static struct fsg_common fsg_common;

/*-------------------------------------------------------------------------*/
static unsigned char tty_line;
static struct usb_function *f_acm;
static struct usb_function_instance *f_acm_inst;
/*
 * We _always_ have both ACM and mass storage functions.
 */
static int __init acm_ms_do_config(struct usb_configuration *c)
{
	struct f_serial_opts *opts;
	int	status;

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

	f_acm_inst = usb_get_function_instance("acm");
	if (IS_ERR(f_acm_inst))
		return PTR_ERR(f_acm_inst);

	opts = container_of(f_acm_inst, struct f_serial_opts, func_inst);
	opts->port_num = tty_line;

	f_acm = usb_get_function(f_acm_inst);
	if (IS_ERR(f_acm)) {
		status = PTR_ERR(f_acm);
		goto err_func;
	}

	status = usb_add_function(c, f_acm);
	if (status < 0)
		goto err_conf;

	status = fsg_bind_config(c->cdev, c, &fsg_common);
	if (status < 0)
		goto err_fsg;

	return 0;
err_fsg:
	usb_remove_function(c, f_acm);
err_conf:
	usb_put_function(f_acm);
err_func:
	usb_put_function_instance(f_acm_inst);
	return status;
}

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

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

static int __init acm_ms_bind(struct usb_composite_dev *cdev)
{
	struct usb_gadget	*gadget = cdev->gadget;
	int			status;
	void			*retp;

	/* set up serial link layer */
	status = gserial_alloc_line(&tty_line);
	if (status < 0)
		return status;

	/* set up mass storage function */
	retp = fsg_common_from_params(&fsg_common, cdev, &fsg_mod_data);
	if (IS_ERR(retp)) {
		status = PTR_ERR(retp);
		goto fail0;
	}

	/*
	 * Allocate string descriptor numbers ... note that string
	 * contents can be overridden by the composite_dev glue.
	 */
	status = usb_string_ids_tab(cdev, strings_dev);
	if (status < 0)
		goto fail1;
	device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
	device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;

	/* register our configuration */
	status = usb_add_config(cdev, &acm_ms_config_driver, acm_ms_do_config);
	if (status < 0)
		goto fail1;

	usb_composite_overwrite_options(cdev, &coverwrite);
	dev_info(&gadget->dev, "%s, version: " DRIVER_VERSION "\n",
			DRIVER_DESC);
	fsg_common_put(&fsg_common);
	return 0;

	/* error recovery */
fail1:
	fsg_common_put(&fsg_common);
fail0:
	gserial_free_line(tty_line);
	return status;
}

static int __exit acm_ms_unbind(struct usb_composite_dev *cdev)
{
	usb_put_function(f_acm);
	usb_put_function_instance(f_acm_inst);
	gserial_free_line(tty_line);
	return 0;
}

static __refdata struct usb_composite_driver acm_ms_driver = {
	.name		= "g_acm_ms",
	.dev		= &device_desc,
	.max_speed	= USB_SPEED_SUPER,
	.strings	= dev_strings,
	.bind		= acm_ms_bind,
	.unbind		= __exit_p(acm_ms_unbind),
};

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("Klaus Schwarzkopf <schwarzkopf@sensortherm.de>");
MODULE_LICENSE("GPL v2");

static int __init init(void)
{
	return usb_composite_probe(&acm_ms_driver);
}
module_init(init);

static void __exit cleanup(void)
{
	usb_composite_unregister(&acm_ms_driver);
}
module_exit(cleanup);