drivers/usb/gadget/f_obex.c - fp2-dev/kernel/msm - Gitiles

 /*
  * f_obex.c -- USB CDC OBEX function driver
  *
  * Copyright (C) 2008 Nokia Corporation
  * Contact: Felipe Balbi <felipe.balbi@nokia.com>
  *
  * Based on f_acm.c by Al Borchers and David Brownell.
  *
  * 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.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */

 /* #define VERBOSE_DEBUG */

 #include <linux/kernel.h>
 #include <linux/utsname.h>
 #include <linux/device.h>

 #include "u_serial.h"
 #include "gadget_chips.h"


 /*
  * This CDC OBEX function support just packages a TTY-ish byte stream.
  * A user mode server will put it into "raw" mode and handle all the
  * relevant protocol details ... this is just a kernel passthrough.
  * When possible, we prevent gadget enumeration until that server is
  * ready to handle the commands.
  */

 struct obex_ep_descs {
 	struct usb_endpoint_descriptor	*obex_in;
 	struct usb_endpoint_descriptor	*obex_out;
 };

 struct f_obex {
 	struct gserial			port;
 	u8				ctrl_id;
 	u8				data_id;
 	u8				port_num;
 	u8				can_activate;

 	struct obex_ep_descs		fs;
 	struct obex_ep_descs		hs;
 };

 static inline struct f_obex *func_to_obex(struct usb_function *f)
 {
 	return container_of(f, struct f_obex, port.func);
 }

 static inline struct f_obex *port_to_obex(struct gserial *p)
 {
 	return container_of(p, struct f_obex, port);
 }

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

 #define OBEX_CTRL_IDX	0
 #define OBEX_DATA_IDX	1

 static struct usb_string obex_string_defs[] = {
 	[OBEX_CTRL_IDX].s	= "CDC Object Exchange (OBEX)",
 	[OBEX_DATA_IDX].s	= "CDC OBEX Data",
 	{  },	/* end of list */
 };

 static struct usb_gadget_strings obex_string_table = {
 	.language		= 0x0409,	/* en-US */
 	.strings		= obex_string_defs,
 };

 static struct usb_gadget_strings *obex_strings[] = {
 	&obex_string_table,
 	NULL,
 };

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

 static struct usb_interface_descriptor obex_control_intf __initdata = {
 	.bLength		= sizeof(obex_control_intf),
 	.bDescriptorType	= USB_DT_INTERFACE,
 	.bInterfaceNumber	= 0,

 	.bAlternateSetting	= 0,
 	.bNumEndpoints		= 0,
 	.bInterfaceClass	= USB_CLASS_COMM,
 	.bInterfaceSubClass	= USB_CDC_SUBCLASS_OBEX,
 };

 static struct usb_interface_descriptor obex_data_nop_intf __initdata = {
 	.bLength		= sizeof(obex_data_nop_intf),
 	.bDescriptorType	= USB_DT_INTERFACE,
 	.bInterfaceNumber	= 1,

 	.bAlternateSetting	= 0,
 	.bNumEndpoints		= 0,
 	.bInterfaceClass	= USB_CLASS_CDC_DATA,
 };

 static struct usb_interface_descriptor obex_data_intf __initdata = {
 	.bLength		= sizeof(obex_data_intf),
 	.bDescriptorType	= USB_DT_INTERFACE,
 	.bInterfaceNumber	= 2,

 	.bAlternateSetting	= 1,
 	.bNumEndpoints		= 2,
 	.bInterfaceClass	= USB_CLASS_CDC_DATA,
 };

 static struct usb_cdc_header_desc obex_cdc_header_desc __initdata = {
 	.bLength		= sizeof(obex_cdc_header_desc),
 	.bDescriptorType	= USB_DT_CS_INTERFACE,
 	.bDescriptorSubType	= USB_CDC_HEADER_TYPE,
 	.bcdCDC			= cpu_to_le16(0x0120),
 };

 static struct usb_cdc_union_desc obex_cdc_union_desc __initdata = {
 	.bLength		= sizeof(obex_cdc_union_desc),
 	.bDescriptorType	= USB_DT_CS_INTERFACE,
 	.bDescriptorSubType	= USB_CDC_UNION_TYPE,
 	.bMasterInterface0	= 1,
 	.bSlaveInterface0	= 2,
 };

 static struct usb_cdc_obex_desc obex_desc __initdata = {
 	.bLength		= sizeof(obex_desc),
 	.bDescriptorType	= USB_DT_CS_INTERFACE,
 	.bDescriptorSubType	= USB_CDC_OBEX_TYPE,
 	.bcdVersion		= cpu_to_le16(0x0100),
 };

 /* High-Speed Support */

 static struct usb_endpoint_descriptor obex_hs_ep_out_desc __initdata = {
 	.bLength		= USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType	= USB_DT_ENDPOINT,

 	.bEndpointAddress	= USB_DIR_OUT,
 	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
 	.wMaxPacketSize		= cpu_to_le16(512),
 };

 static struct usb_endpoint_descriptor obex_hs_ep_in_desc __initdata = {
 	.bLength		= USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType	= USB_DT_ENDPOINT,

 	.bEndpointAddress	= USB_DIR_IN,
 	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
 	.wMaxPacketSize		= cpu_to_le16(512),
 };

 static struct usb_descriptor_header *hs_function[] __initdata = {
 	(struct usb_descriptor_header *) &obex_control_intf,
 	(struct usb_descriptor_header *) &obex_cdc_header_desc,
 	(struct usb_descriptor_header *) &obex_desc,
 	(struct usb_descriptor_header *) &obex_cdc_union_desc,

 	(struct usb_descriptor_header *) &obex_data_nop_intf,
 	(struct usb_descriptor_header *) &obex_data_intf,
 	(struct usb_descriptor_header *) &obex_hs_ep_in_desc,
 	(struct usb_descriptor_header *) &obex_hs_ep_out_desc,
 	NULL,
 };

 /* Full-Speed Support */

 static struct usb_endpoint_descriptor obex_fs_ep_in_desc __initdata = {
 	.bLength		= USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType	= USB_DT_ENDPOINT,

 	.bEndpointAddress	= USB_DIR_IN,
 	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
 };

 static struct usb_endpoint_descriptor obex_fs_ep_out_desc __initdata = {
 	.bLength		= USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType	= USB_DT_ENDPOINT,

 	.bEndpointAddress	= USB_DIR_OUT,
 	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
 };

 static struct usb_descriptor_header *fs_function[] __initdata = {
 	(struct usb_descriptor_header *) &obex_control_intf,
 	(struct usb_descriptor_header *) &obex_cdc_header_desc,
 	(struct usb_descriptor_header *) &obex_desc,
 	(struct usb_descriptor_header *) &obex_cdc_union_desc,

 	(struct usb_descriptor_header *) &obex_data_nop_intf,
 	(struct usb_descriptor_header *) &obex_data_intf,
 	(struct usb_descriptor_header *) &obex_fs_ep_in_desc,
 	(struct usb_descriptor_header *) &obex_fs_ep_out_desc,
 	NULL,
 };

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

 static int obex_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 {
 	struct f_obex		*obex = func_to_obex(f);
 	struct usb_composite_dev *cdev = f->config->cdev;

 	if (intf == obex->ctrl_id) {
 		if (alt != 0)
 			goto fail;
 		/* NOP */
 		DBG(cdev, "reset obex ttyGS%d control\n", obex->port_num);

 	} else if (intf == obex->data_id) {
 		if (alt > 1)
 			goto fail;

 		if (obex->port.in->driver_data) {
 			DBG(cdev, "reset obex ttyGS%d\n", obex->port_num);
 			gserial_disconnect(&obex->port);
 		}

 		if (!obex->port.in_desc) {
 			DBG(cdev, "init obex ttyGS%d\n", obex->port_num);
 			obex->port.in_desc = ep_choose(cdev->gadget,
 					obex->hs.obex_in, obex->fs.obex_in);
 			obex->port.out_desc = ep_choose(cdev->gadget,
 					obex->hs.obex_out, obex->fs.obex_out);
 		}

 		if (alt == 1) {
 			DBG(cdev, "activate obex ttyGS%d\n", obex->port_num);
 			gserial_connect(&obex->port, obex->port_num);
 		}

 	} else
 		goto fail;

 	return 0;

 fail:
 	return -EINVAL;
 }

 static int obex_get_alt(struct usb_function *f, unsigned intf)
 {
 	struct f_obex		*obex = func_to_obex(f);

 	if (intf == obex->ctrl_id)
 		return 0;

 	return obex->port.in->driver_data ? 1 : 0;
 }

 static void obex_disable(struct usb_function *f)
 {
 	struct f_obex	*obex = func_to_obex(f);
 	struct usb_composite_dev *cdev = f->config->cdev;

 	DBG(cdev, "obex ttyGS%d disable\n", obex->port_num);
 	gserial_disconnect(&obex->port);
 }

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

 static void obex_connect(struct gserial *g)
 {
 	struct f_obex		*obex = port_to_obex(g);
 	struct usb_composite_dev *cdev = g->func.config->cdev;
 	int			status;

 	if (!obex->can_activate)
 		return;

 	status = usb_function_activate(&g->func);
 	if (status)
 		DBG(cdev, "obex ttyGS%d function activate --> %d\n",
 			obex->port_num, status);
 }

 static void obex_disconnect(struct gserial *g)
 {
 	struct f_obex		*obex = port_to_obex(g);
 	struct usb_composite_dev *cdev = g->func.config->cdev;
 	int			status;

 	if (!obex->can_activate)
 		return;

 	status = usb_function_deactivate(&g->func);
 	if (status)
 		DBG(cdev, "obex ttyGS%d function deactivate --> %d\n",
 			obex->port_num, status);
 }

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

 static int __init
 obex_bind(struct usb_configuration *c, struct usb_function *f)
 {
 	struct usb_composite_dev *cdev = c->cdev;
 	struct f_obex		*obex = func_to_obex(f);
 	int			status;
 	struct usb_ep		*ep;

 	/* allocate instance-specific interface IDs, and patch descriptors */

 	status = usb_interface_id(c, f);
 	if (status < 0)
 		goto fail;
 	obex->ctrl_id = status;

 	obex_control_intf.bInterfaceNumber = status;
 	obex_cdc_union_desc.bMasterInterface0 = status;

 	status = usb_interface_id(c, f);
 	if (status < 0)
 		goto fail;
 	obex->data_id = status;

 	obex_data_nop_intf.bInterfaceNumber = status;
 	obex_data_intf.bInterfaceNumber = status;
 	obex_cdc_union_desc.bSlaveInterface0 = status;

 	/* allocate instance-specific endpoints */

 	ep = usb_ep_autoconfig(cdev->gadget, &obex_fs_ep_in_desc);
 	if (!ep)
 		goto fail;
 	obex->port.in = ep;
 	ep->driver_data = cdev;	/* claim */

 	ep = usb_ep_autoconfig(cdev->gadget, &obex_fs_ep_out_desc);
 	if (!ep)
 		goto fail;
 	obex->port.out = ep;
 	ep->driver_data = cdev;	/* claim */

 	/* copy descriptors, and track endpoint copies */
 	f->descriptors = usb_copy_descriptors(fs_function);

 	obex->fs.obex_in = usb_find_endpoint(fs_function,
 			f->descriptors, &obex_fs_ep_in_desc);
 	obex->fs.obex_out = usb_find_endpoint(fs_function,
 			f->descriptors, &obex_fs_ep_out_desc);

 	/* support all relevant hardware speeds... we expect that when
 	 * hardware is dual speed, all bulk-capable endpoints work at
 	 * both speeds
 	 */
 	if (gadget_is_dualspeed(c->cdev->gadget)) {

 		obex_hs_ep_in_desc.bEndpointAddress =
 				obex_fs_ep_in_desc.bEndpointAddress;
 		obex_hs_ep_out_desc.bEndpointAddress =
 				obex_fs_ep_out_desc.bEndpointAddress;

 		/* copy descriptors, and track endpoint copies */
 		f->hs_descriptors = usb_copy_descriptors(hs_function);

 		obex->hs.obex_in = usb_find_endpoint(hs_function,
 				f->hs_descriptors, &obex_hs_ep_in_desc);
 		obex->hs.obex_out = usb_find_endpoint(hs_function,
 				f->hs_descriptors, &obex_hs_ep_out_desc);
 	}

 	/* Avoid letting this gadget enumerate until the userspace
 	 * OBEX server is active.
 	 */
 	status = usb_function_deactivate(f);
 	if (status < 0)
 		WARNING(cdev, "obex ttyGS%d: can't prevent enumeration, %d\n",
 			obex->port_num, status);
 	else
 		obex->can_activate = true;


 	DBG(cdev, "obex ttyGS%d: %s speed IN/%s OUT/%s\n",
 			obex->port_num,
 			gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
 			obex->port.in->name, obex->port.out->name);

 	return 0;

 fail:
 	/* we might as well release our claims on endpoints */
 	if (obex->port.out)
 		obex->port.out->driver_data = NULL;
 	if (obex->port.in)
 		obex->port.in->driver_data = NULL;

 	ERROR(cdev, "%s/%p: can't bind, err %d\n", f->name, f, status);

 	return status;
 }

 static void
 obex_unbind(struct usb_configuration *c, struct usb_function *f)
 {
 	if (gadget_is_dualspeed(c->cdev->gadget))
 		usb_free_descriptors(f->hs_descriptors);
 	usb_free_descriptors(f->descriptors);
 	kfree(func_to_obex(f));
 }

 /* Some controllers can't support CDC OBEX ... */
 static inline bool can_support_obex(struct usb_configuration *c)
 {
 	/* Since the first interface is a NOP, we can ignore the
 	 * issue of multi-interface support on most controllers.
 	 *
 	 * Altsettings are mandatory, however...
 	 */
 	if (!gadget_supports_altsettings(c->cdev->gadget))
 		return false;

 	/* everything else is *probably* fine ... */
 	return true;
 }

 /**
  * obex_bind_config - add a CDC OBEX function to a configuration
  * @c: the configuration to support the CDC OBEX instance
  * @port_num: /dev/ttyGS* port this interface will use
  * Context: single threaded during gadget setup
  *
  * Returns zero on success, else negative errno.
  *
  * Caller must have called @gserial_setup() with enough ports to
  * handle all the ones it binds.  Caller is also responsible
  * for calling @gserial_cleanup() before module unload.
  */
 int __init obex_bind_config(struct usb_configuration *c, u8 port_num)
 {
 	struct f_obex	*obex;
 	int		status;

 	if (!can_support_obex(c))
 		return -EINVAL;

 	/* maybe allocate device-global string IDs, and patch descriptors */
 	if (obex_string_defs[OBEX_CTRL_IDX].id == 0) {
 		status = usb_string_id(c->cdev);
 		if (status < 0)
 			return status;
 		obex_string_defs[OBEX_CTRL_IDX].id = status;

 		obex_control_intf.iInterface = status;

 		status = usb_string_id(c->cdev);
 		if (status < 0)
 			return status;
 		obex_string_defs[OBEX_DATA_IDX].id = status;

 		obex_data_nop_intf.iInterface =
 			obex_data_intf.iInterface = status;
 	}

 	/* allocate and initialize one new instance */
 	obex = kzalloc(sizeof *obex, GFP_KERNEL);
 	if (!obex)
 		return -ENOMEM;

 	obex->port_num = port_num;

 	obex->port.connect = obex_connect;
 	obex->port.disconnect = obex_disconnect;

 	obex->port.func.name = "obex";
 	obex->port.func.strings = obex_strings;
 	/* descriptors are per-instance copies */
 	obex->port.func.bind = obex_bind;
 	obex->port.func.unbind = obex_unbind;
 	obex->port.func.set_alt = obex_set_alt;
 	obex->port.func.get_alt = obex_get_alt;
 	obex->port.func.disable = obex_disable;

 	status = usb_add_function(c, &obex->port.func);
 	if (status)
 		kfree(obex);

 	return status;
 }

 MODULE_AUTHOR("Felipe Balbi");
 MODULE_LICENSE("GPL");
	/*
	* f_obex.c -- USB CDC OBEX function driver
	*
	* Copyright (C) 2008 Nokia Corporation
	* Contact: Felipe Balbi <felipe.balbi@nokia.com>
	*
	* Based on f_acm.c by Al Borchers and David Brownell.
	*
	* 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.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*/

	/* #define VERBOSE_DEBUG */

	#include <linux/kernel.h>
	#include <linux/utsname.h>
	#include <linux/device.h>

	#include "u_serial.h"
	#include "gadget_chips.h"


	/*
	* This CDC OBEX function support just packages a TTY-ish byte stream.
	* A user mode server will put it into "raw" mode and handle all the
	* relevant protocol details ... this is just a kernel passthrough.
	* When possible, we prevent gadget enumeration until that server is
	* ready to handle the commands.
	*/

	struct obex_ep_descs {
	struct usb_endpoint_descriptor *obex_in;
	struct usb_endpoint_descriptor *obex_out;
	};

	struct f_obex {
	struct gserial port;
	u8 ctrl_id;
	u8 data_id;
	u8 port_num;
	u8 can_activate;

	struct obex_ep_descs fs;
	struct obex_ep_descs hs;
	};

	static inline struct f_obex func_to_obex(struct usb_function f)
	{
	return container_of(f, struct f_obex, port.func);
	}

	static inline struct f_obex port_to_obex(struct gserial p)
	{
	return container_of(p, struct f_obex, port);
	}

	/-------------------------------------------------------------------------/

	#define OBEX_CTRL_IDX 0
	#define OBEX_DATA_IDX 1

	static struct usb_string obex_string_defs[] = {
	[OBEX_CTRL_IDX].s = "CDC Object Exchange (OBEX)",
	[OBEX_DATA_IDX].s = "CDC OBEX Data",
	{ }, /* end of list */
	};

	static struct usb_gadget_strings obex_string_table = {
	.language = 0x0409, /* en-US */
	.strings = obex_string_defs,
	};

	static struct usb_gadget_strings *obex_strings[] = {
	&obex_string_table,
	NULL,
	};

	/-------------------------------------------------------------------------/

	static struct usb_interface_descriptor obex_control_intf __initdata = {
	.bLength = sizeof(obex_control_intf),
	.bDescriptorType = USB_DT_INTERFACE,
	.bInterfaceNumber = 0,

	.bAlternateSetting = 0,
	.bNumEndpoints = 0,
	.bInterfaceClass = USB_CLASS_COMM,
	.bInterfaceSubClass = USB_CDC_SUBCLASS_OBEX,
	};

	static struct usb_interface_descriptor obex_data_nop_intf __initdata = {
	.bLength = sizeof(obex_data_nop_intf),
	.bDescriptorType = USB_DT_INTERFACE,
	.bInterfaceNumber = 1,

	.bAlternateSetting = 0,
	.bNumEndpoints = 0,
	.bInterfaceClass = USB_CLASS_CDC_DATA,
	};

	static struct usb_interface_descriptor obex_data_intf __initdata = {
	.bLength = sizeof(obex_data_intf),
	.bDescriptorType = USB_DT_INTERFACE,
	.bInterfaceNumber = 2,

	.bAlternateSetting = 1,
	.bNumEndpoints = 2,
	.bInterfaceClass = USB_CLASS_CDC_DATA,
	};

	static struct usb_cdc_header_desc obex_cdc_header_desc __initdata = {
	.bLength = sizeof(obex_cdc_header_desc),
	.bDescriptorType = USB_DT_CS_INTERFACE,
	.bDescriptorSubType = USB_CDC_HEADER_TYPE,
	.bcdCDC = cpu_to_le16(0x0120),
	};

	static struct usb_cdc_union_desc obex_cdc_union_desc __initdata = {
	.bLength = sizeof(obex_cdc_union_desc),
	.bDescriptorType = USB_DT_CS_INTERFACE,
	.bDescriptorSubType = USB_CDC_UNION_TYPE,
	.bMasterInterface0 = 1,
	.bSlaveInterface0 = 2,
	};

	static struct usb_cdc_obex_desc obex_desc __initdata = {
	.bLength = sizeof(obex_desc),
	.bDescriptorType = USB_DT_CS_INTERFACE,
	.bDescriptorSubType = USB_CDC_OBEX_TYPE,
	.bcdVersion = cpu_to_le16(0x0100),
	};

	/* High-Speed Support */

	static struct usb_endpoint_descriptor obex_hs_ep_out_desc __initdata = {
	.bLength = USB_DT_ENDPOINT_SIZE,
	.bDescriptorType = USB_DT_ENDPOINT,

	.bEndpointAddress = USB_DIR_OUT,
	.bmAttributes = USB_ENDPOINT_XFER_BULK,
	.wMaxPacketSize = cpu_to_le16(512),
	};

	static struct usb_endpoint_descriptor obex_hs_ep_in_desc __initdata = {
	.bLength = USB_DT_ENDPOINT_SIZE,
	.bDescriptorType = USB_DT_ENDPOINT,

	.bEndpointAddress = USB_DIR_IN,
	.bmAttributes = USB_ENDPOINT_XFER_BULK,
	.wMaxPacketSize = cpu_to_le16(512),
	};

	static struct usb_descriptor_header *hs_function[] __initdata = {
	(struct usb_descriptor_header *) &obex_control_intf,
	(struct usb_descriptor_header *) &obex_cdc_header_desc,
	(struct usb_descriptor_header *) &obex_desc,
	(struct usb_descriptor_header *) &obex_cdc_union_desc,

	(struct usb_descriptor_header *) &obex_data_nop_intf,
	(struct usb_descriptor_header *) &obex_data_intf,
	(struct usb_descriptor_header *) &obex_hs_ep_in_desc,
	(struct usb_descriptor_header *) &obex_hs_ep_out_desc,
	NULL,
	};

	/* Full-Speed Support */

	static struct usb_endpoint_descriptor obex_fs_ep_in_desc __initdata = {
	.bLength = USB_DT_ENDPOINT_SIZE,
	.bDescriptorType = USB_DT_ENDPOINT,

	.bEndpointAddress = USB_DIR_IN,
	.bmAttributes = USB_ENDPOINT_XFER_BULK,
	};

	static struct usb_endpoint_descriptor obex_fs_ep_out_desc __initdata = {
	.bLength = USB_DT_ENDPOINT_SIZE,
	.bDescriptorType = USB_DT_ENDPOINT,

	.bEndpointAddress = USB_DIR_OUT,
	.bmAttributes = USB_ENDPOINT_XFER_BULK,
	};

	static struct usb_descriptor_header *fs_function[] __initdata = {
	(struct usb_descriptor_header *) &obex_control_intf,
	(struct usb_descriptor_header *) &obex_cdc_header_desc,
	(struct usb_descriptor_header *) &obex_desc,
	(struct usb_descriptor_header *) &obex_cdc_union_desc,

	(struct usb_descriptor_header *) &obex_data_nop_intf,
	(struct usb_descriptor_header *) &obex_data_intf,
	(struct usb_descriptor_header *) &obex_fs_ep_in_desc,
	(struct usb_descriptor_header *) &obex_fs_ep_out_desc,
	NULL,
	};

	/-------------------------------------------------------------------------/

	static int obex_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
	{
	struct f_obex *obex = func_to_obex(f);
	struct usb_composite_dev *cdev = f->config->cdev;

	if (intf == obex->ctrl_id) {
	if (alt != 0)
	goto fail;
	/* NOP */
	DBG(cdev, "reset obex ttyGS%d control\n", obex->port_num);

	} else if (intf == obex->data_id) {
	if (alt > 1)
	goto fail;

	if (obex->port.in->driver_data) {
	DBG(cdev, "reset obex ttyGS%d\n", obex->port_num);
	gserial_disconnect(&obex->port);
	}

	if (!obex->port.in_desc) {
	DBG(cdev, "init obex ttyGS%d\n", obex->port_num);
	obex->port.in_desc = ep_choose(cdev->gadget,
	obex->hs.obex_in, obex->fs.obex_in);
	obex->port.out_desc = ep_choose(cdev->gadget,
	obex->hs.obex_out, obex->fs.obex_out);
	}

	if (alt == 1) {
	DBG(cdev, "activate obex ttyGS%d\n", obex->port_num);
	gserial_connect(&obex->port, obex->port_num);
	}

	} else
	goto fail;

	return 0;

	fail:
	return -EINVAL;
	}

	static int obex_get_alt(struct usb_function *f, unsigned intf)
	{
	struct f_obex *obex = func_to_obex(f);

	if (intf == obex->ctrl_id)
	return 0;

	return obex->port.in->driver_data ? 1 : 0;
	}

	static void obex_disable(struct usb_function *f)
	{
	struct f_obex *obex = func_to_obex(f);
	struct usb_composite_dev *cdev = f->config->cdev;

	DBG(cdev, "obex ttyGS%d disable\n", obex->port_num);
	gserial_disconnect(&obex->port);
	}

	/-------------------------------------------------------------------------/

	static void obex_connect(struct gserial *g)
	{
	struct f_obex *obex = port_to_obex(g);
	struct usb_composite_dev *cdev = g->func.config->cdev;
	int status;

	if (!obex->can_activate)
	return;

	status = usb_function_activate(&g->func);
	if (status)
	DBG(cdev, "obex ttyGS%d function activate --> %d\n",
	obex->port_num, status);
	}

	static void obex_disconnect(struct gserial *g)
	{
	struct f_obex *obex = port_to_obex(g);
	struct usb_composite_dev *cdev = g->func.config->cdev;
	int status;

	if (!obex->can_activate)
	return;

	status = usb_function_deactivate(&g->func);
	if (status)
	DBG(cdev, "obex ttyGS%d function deactivate --> %d\n",
	obex->port_num, status);
	}

	/-------------------------------------------------------------------------/

	static int __init
	obex_bind(struct usb_configuration c, struct usb_function f)
	{
	struct usb_composite_dev *cdev = c->cdev;
	struct f_obex *obex = func_to_obex(f);
	int status;
	struct usb_ep *ep;

	/* allocate instance-specific interface IDs, and patch descriptors */

	status = usb_interface_id(c, f);
	if (status < 0)
	goto fail;
	obex->ctrl_id = status;

	obex_control_intf.bInterfaceNumber = status;
	obex_cdc_union_desc.bMasterInterface0 = status;

	status = usb_interface_id(c, f);
	if (status < 0)
	goto fail;
	obex->data_id = status;

	obex_data_nop_intf.bInterfaceNumber = status;
	obex_data_intf.bInterfaceNumber = status;
	obex_cdc_union_desc.bSlaveInterface0 = status;

	/* allocate instance-specific endpoints */

	ep = usb_ep_autoconfig(cdev->gadget, &obex_fs_ep_in_desc);
	if (!ep)
	goto fail;
	obex->port.in = ep;
	ep->driver_data = cdev; /* claim */

	ep = usb_ep_autoconfig(cdev->gadget, &obex_fs_ep_out_desc);
	if (!ep)
	goto fail;
	obex->port.out = ep;
	ep->driver_data = cdev; /* claim */

	/* copy descriptors, and track endpoint copies */
	f->descriptors = usb_copy_descriptors(fs_function);

	obex->fs.obex_in = usb_find_endpoint(fs_function,
	f->descriptors, &obex_fs_ep_in_desc);
	obex->fs.obex_out = usb_find_endpoint(fs_function,
	f->descriptors, &obex_fs_ep_out_desc);

	/* support all relevant hardware speeds... we expect that when
	* hardware is dual speed, all bulk-capable endpoints work at
	* both speeds
	*/
	if (gadget_is_dualspeed(c->cdev->gadget)) {

	obex_hs_ep_in_desc.bEndpointAddress =
	obex_fs_ep_in_desc.bEndpointAddress;
	obex_hs_ep_out_desc.bEndpointAddress =
	obex_fs_ep_out_desc.bEndpointAddress;

	/* copy descriptors, and track endpoint copies */
	f->hs_descriptors = usb_copy_descriptors(hs_function);

	obex->hs.obex_in = usb_find_endpoint(hs_function,
	f->hs_descriptors, &obex_hs_ep_in_desc);
	obex->hs.obex_out = usb_find_endpoint(hs_function,
	f->hs_descriptors, &obex_hs_ep_out_desc);
	}

	/* Avoid letting this gadget enumerate until the userspace
	* OBEX server is active.
	*/
	status = usb_function_deactivate(f);
	if (status < 0)
	WARNING(cdev, "obex ttyGS%d: can't prevent enumeration, %d\n",
	obex->port_num, status);
	else
	obex->can_activate = true;


	DBG(cdev, "obex ttyGS%d: %s speed IN/%s OUT/%s\n",
	obex->port_num,
	gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
	obex->port.in->name, obex->port.out->name);

	return 0;

	fail:
	/* we might as well release our claims on endpoints */
	if (obex->port.out)
	obex->port.out->driver_data = NULL;
	if (obex->port.in)
	obex->port.in->driver_data = NULL;

	ERROR(cdev, "%s/%p: can't bind, err %d\n", f->name, f, status);

	return status;
	}

	static void
	obex_unbind(struct usb_configuration c, struct usb_function f)
	{
	if (gadget_is_dualspeed(c->cdev->gadget))
	usb_free_descriptors(f->hs_descriptors);
	usb_free_descriptors(f->descriptors);
	kfree(func_to_obex(f));
	}

	/* Some controllers can't support CDC OBEX ... */
	static inline bool can_support_obex(struct usb_configuration *c)
	{
	/* Since the first interface is a NOP, we can ignore the
	* issue of multi-interface support on most controllers.
	*
	* Altsettings are mandatory, however...
	*/
	if (!gadget_supports_altsettings(c->cdev->gadget))
	return false;

	/* everything else is probably fine ... */
	return true;
	}

	/**
	* obex_bind_config - add a CDC OBEX function to a configuration
	* @c: the configuration to support the CDC OBEX instance
	* @port_num: /dev/ttyGS* port this interface will use
	* Context: single threaded during gadget setup
	*
	* Returns zero on success, else negative errno.
	*
	* Caller must have called @gserial_setup() with enough ports to
	* handle all the ones it binds. Caller is also responsible
	* for calling @gserial_cleanup() before module unload.
	*/
	int __init obex_bind_config(struct usb_configuration *c, u8 port_num)
	{
	struct f_obex *obex;
	int status;

	if (!can_support_obex(c))
	return -EINVAL;

	/* maybe allocate device-global string IDs, and patch descriptors */
	if (obex_string_defs[OBEX_CTRL_IDX].id == 0) {
	status = usb_string_id(c->cdev);
	if (status < 0)
	return status;
	obex_string_defs[OBEX_CTRL_IDX].id = status;

	obex_control_intf.iInterface = status;

	status = usb_string_id(c->cdev);
	if (status < 0)
	return status;
	obex_string_defs[OBEX_DATA_IDX].id = status;

	obex_data_nop_intf.iInterface =
	obex_data_intf.iInterface = status;
	}

	/* allocate and initialize one new instance */
	obex = kzalloc(sizeof *obex, GFP_KERNEL);
	if (!obex)
	return -ENOMEM;

	obex->port_num = port_num;

	obex->port.connect = obex_connect;
	obex->port.disconnect = obex_disconnect;

	obex->port.func.name = "obex";
	obex->port.func.strings = obex_strings;
	/* descriptors are per-instance copies */
	obex->port.func.bind = obex_bind;
	obex->port.func.unbind = obex_unbind;
	obex->port.func.set_alt = obex_set_alt;
	obex->port.func.get_alt = obex_get_alt;
	obex->port.func.disable = obex_disable;

	status = usb_add_function(c, &obex->port.func);
	if (status)
	kfree(obex);

	return status;
	}

	MODULE_AUTHOR("Felipe Balbi");
	MODULE_LICENSE("GPL");