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Commit 08cce56f authored by Ajay Agarwal's avatar Ajay Agarwal Committed by Gerrit - the friendly Code Review server
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usb: misc: Add snapshot of diag_bridge driver 



USB diag host driver will be used to connect diag interface
exposed by Qualcomm devices. This is a snapshot of diag_bridge
driver from kernel msm-3.10 'commit 680769b57a70
("wcnss: Fix buffer overflow in wcnss_prealloc_get")'. Fix
checkpatch failures and minor code improvements.

Change-Id: Ide503c5bf729a7e41de98b12c89e4edc12af61fe
Signed-off-by: default avatarAjay Agarwal <ajaya@codeaurora.org>
parent 59f01699

drivers/usb/misc/Kconfig

+11 −0
Original line number Diff line number Diff line
@@ -287,3 +287,14 @@ config USB_TYPEC_MUX_NXP5150A 
	help

	  Say Y here if you want to use NXP CC Logic Type-C Chipset NXP5150A

	  for CC detection and Mux control.



config USB_QCOM_DIAG_BRIDGE

	tristate "USB QTI diagnostic bridge driver"

	depends on USB

	help

	  Say Y here if you have a QTI modem device connected via USB that

	  will be bridged in kernel space. This driver communicates with the

	  diagnostic interface and allows for bridging with the diag forwarding

	  driver.

	  To compile this driver as a module, choose M here: the

	  module will be called diag_bridge.  If unsure, choose N.

drivers/usb/misc/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -33,3 +33,4 @@ obj-$(CONFIG_USB_TYPEC_MUX_NXP5150A) += nxp_typec.o 
obj-$(CONFIG_USB_SISUSBVGA)		+= sisusbvga/

obj-$(CONFIG_USB_LINK_LAYER_TEST)	+= lvstest.o

obj-$(CONFIG_USB_REDRIVER_NB7VPQ904M)	+= ssusb-redriver-nb7vpq904m.o

obj-$(CONFIG_USB_QCOM_DIAG_BRIDGE)	+= diag_bridge.o

drivers/usb/misc/diag_bridge.c

0 → 100644
+662 −0
Original line number Diff line number Diff line 
/* Copyright (c) 2011-2015, 2019, The Linux Foundation. All rights reserved.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 and

 * only version 2 as published by the Free Software Foundation.

 *

 * 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.

 */



/* add additional information to our printk's */

#define pr_fmt(fmt) "%s: " fmt "\n", __func__



#include <linux/kernel.h>

#include <linux/errno.h>

#include <linux/init.h>

#include <linux/slab.h>

#include <linux/module.h>

#include <linux/kref.h>

#include <linux/mutex.h>

#include <linux/platform_device.h>

#include <linux/ratelimit.h>

#include <linux/uaccess.h>

#include <linux/usb.h>

#include <linux/debugfs.h>

#include <linux/usb/diag_bridge.h>



#define DRIVER_DESC	"USB host diag bridge driver"

#define DRIVER_VERSION	"1.0"



#define MAX_DIAG_BRIDGE_DEVS	2

#define AUTOSUSP_DELAY_WITH_USB 1000



struct diag_bridge {

	struct usb_device	*udev;

	struct usb_interface	*ifc;

	struct usb_anchor	submitted;

	__u8			in_epAddr;

	__u8			out_epAddr;

	int			err;

	struct kref		kref;

	struct mutex		ifc_mutex;

	struct diag_bridge_ops	*ops;

	struct platform_device	*pdev;

	unsigned int		default_autosusp_delay;

	int			id;



	/* Support INT IN instead of BULK IN */

	bool			use_int_in_pipe;

	unsigned int		period;



	/* debugging counters */

	unsigned long		bytes_to_host;

	unsigned long		bytes_to_mdm;

	unsigned int		pending_reads;

	unsigned int		pending_writes;

	unsigned int		drop_count;

};

struct diag_bridge *__dev[MAX_DIAG_BRIDGE_DEVS];



int diag_bridge_open(int id, struct diag_bridge_ops *ops)

{

	struct diag_bridge	*dev;



	if (id < 0 || id >= MAX_DIAG_BRIDGE_DEVS) {

		pr_err("Invalid device ID");

		return -ENODEV;

	}



	dev = __dev[id];

	if (!dev) {

		pr_err("dev is null");

		return -ENODEV;

	}



	if (dev->ops) {

		pr_err("bridge already opened");

		return -EALREADY;

	}



	dev->ops = ops;

	dev->err = 0;



	if (!id) {

#ifdef CONFIG_PM_RUNTIME

		dev->default_autosusp_delay =

			dev->udev->dev.power.autosuspend_delay;

#endif

		pm_runtime_set_autosuspend_delay(&dev->udev->dev,

				AUTOSUSP_DELAY_WITH_USB);

	}



	kref_get(&dev->kref);



	return 0;

}

EXPORT_SYMBOL(diag_bridge_open);



static void diag_bridge_delete(struct kref *kref)

{

	struct diag_bridge *dev = container_of(kref, struct diag_bridge, kref);

	int id = dev->id;



	usb_put_dev(dev->udev);

	__dev[id] = 0;

	kfree(dev);

}



void diag_bridge_close(int id)

{

	struct diag_bridge	*dev;



	if (id < 0 || id >= MAX_DIAG_BRIDGE_DEVS) {

		pr_err("Invalid device ID");

		return;

	}



	dev = __dev[id];

	if (!dev) {

		pr_err("dev is null");

		return;

	}



	if (!dev->ops) {

		pr_err("can't close bridge that was not open");

		return;

	}



	dev_dbg(&dev->ifc->dev, "%s:\n", __func__);



	usb_kill_anchored_urbs(&dev->submitted);

	dev->ops = 0;





	if (!id) {

		pm_runtime_set_autosuspend_delay(&dev->udev->dev,

			dev->default_autosusp_delay);

	}



	kref_put(&dev->kref, diag_bridge_delete);

}

EXPORT_SYMBOL(diag_bridge_close);



static void diag_bridge_read_cb(struct urb *urb)

{

	struct diag_bridge	*dev = urb->context;

	struct diag_bridge_ops	*cbs = dev->ops;



	dev_dbg(&dev->ifc->dev, "%s: status:%d actual:%d\n", __func__,

			urb->status, urb->actual_length);



	/* save error so that subsequent read/write returns ENODEV */

	if (urb->status == -EPROTO)

		dev->err = urb->status;



	if (cbs && cbs->read_complete_cb)

		cbs->read_complete_cb(cbs->ctxt,

			urb->transfer_buffer,

			urb->transfer_buffer_length,

			urb->status < 0 ? urb->status : urb->actual_length);



	dev->bytes_to_host += urb->actual_length;

	dev->pending_reads--;

	kref_put(&dev->kref, diag_bridge_delete);

}



int diag_bridge_read(int id, char *data, int size)

{

	struct urb		*urb = NULL;

	unsigned int		pipe;

	struct diag_bridge	*dev;

	int			ret;



	if (id < 0 || id >= MAX_DIAG_BRIDGE_DEVS) {

		pr_err("Invalid device ID");

		return -ENODEV;

	}



	pr_debug("reading %d bytes", size);



	dev = __dev[id];

	if (!dev) {

		pr_err("device is disconnected");

		return -ENODEV;

	}



	mutex_lock(&dev->ifc_mutex);

	if (!dev->ifc) {

		ret = -ENODEV;

		goto error;

	}



	if (!dev->ops) {

		pr_err("bridge is not open");

		ret = -ENODEV;

		goto error;

	}



	if (!size) {

		dev_dbg(&dev->ifc->dev, "invalid size:%d\n", size);

		dev->drop_count++;

		ret = -EINVAL;

		goto error;

	}



	/* if there was a previous unrecoverable error, just quit */

	if (dev->err) {

		ret = -ENODEV;

		goto error;

	}



	kref_get(&dev->kref);



	urb = usb_alloc_urb(0, GFP_KERNEL);

	if (!urb) {

		dev_dbg(&dev->ifc->dev, "unable to allocate urb\n");

		ret = -ENOMEM;

		goto put_error;

	}



	ret = usb_autopm_get_interface(dev->ifc);

	if (ret < 0 && ret != -EAGAIN && ret != -EACCES) {

		pr_err_ratelimited("read: autopm_get failed:%d", ret);

		goto free_error;

	}



	if (dev->use_int_in_pipe) {

		pipe = usb_rcvintpipe(dev->udev, dev->in_epAddr);

		usb_fill_int_urb(urb, dev->udev, pipe, data, size,

		diag_bridge_read_cb, dev, dev->period);

	} else {

		pipe = usb_rcvbulkpipe(dev->udev, dev->in_epAddr);

		usb_fill_bulk_urb(urb, dev->udev, pipe, data, size,

				diag_bridge_read_cb, dev);

	}



	usb_anchor_urb(urb, &dev->submitted);

	dev->pending_reads++;



	ret = usb_submit_urb(urb, GFP_KERNEL);

	if (ret) {

		pr_err_ratelimited("submitting urb failed err:%d", ret);

		dev->pending_reads--;

		usb_unanchor_urb(urb);

		usb_autopm_put_interface(dev->ifc);

		goto free_error;

	}



	usb_autopm_put_interface(dev->ifc);



free_error:

	usb_free_urb(urb);

put_error:

	if (ret) /* otherwise this is done in the completion handler */

		kref_put(&dev->kref, diag_bridge_delete);

error:

	mutex_unlock(&dev->ifc_mutex);

	return ret;

}

EXPORT_SYMBOL(diag_bridge_read);



static void diag_bridge_write_cb(struct urb *urb)

{

	struct diag_bridge	*dev = urb->context;

	struct diag_bridge_ops	*cbs = dev->ops;



	dev_dbg(&dev->ifc->dev, "%s:\n", __func__);



	usb_autopm_put_interface_async(dev->ifc);



	/* save error so that subsequent read/write returns ENODEV */

	if (urb->status == -EPROTO)

		dev->err = urb->status;



	if (cbs && cbs->write_complete_cb)

		cbs->write_complete_cb(cbs->ctxt,

			urb->transfer_buffer,

			urb->transfer_buffer_length,

			urb->status < 0 ? urb->status : urb->actual_length);



	dev->bytes_to_mdm += urb->actual_length;

	dev->pending_writes--;

	kref_put(&dev->kref, diag_bridge_delete);

}



int diag_bridge_write(int id, char *data, int size)

{

	struct urb		*urb = NULL;

	unsigned int		pipe;

	struct diag_bridge	*dev;

	int			ret;



	if (id < 0 || id >= MAX_DIAG_BRIDGE_DEVS) {

		pr_err("Invalid device ID");

		return -ENODEV;

	}



	pr_debug("writing %d bytes", size);



	dev = __dev[id];

	if (!dev) {

		pr_err("device is disconnected");

		return -ENODEV;

	}



	mutex_lock(&dev->ifc_mutex);

	if (!dev->ifc) {

		ret = -ENODEV;

		goto error;

	}



	if (!dev->ops) {

		pr_err("bridge is not open");

		ret = -ENODEV;

		goto error;

	}



	if (!size) {

		dev_err(&dev->ifc->dev, "invalid size:%d\n", size);

		ret = -EINVAL;

		goto error;

	}



	/* if there was a previous unrecoverable error, just quit */

	if (dev->err) {

		ret = -ENODEV;

		goto error;

	}



	kref_get(&dev->kref);



	urb = usb_alloc_urb(0, GFP_KERNEL);

	if (!urb) {

		dev_err(&dev->ifc->dev, "unable to allocate urb\n");

		ret = -ENOMEM;

		goto put_error;

	}



	ret = usb_autopm_get_interface(dev->ifc);

	if (ret < 0 && ret != -EAGAIN && ret != -EACCES) {

		pr_err_ratelimited("write: autopm_get failed:%d", ret);

		goto free_error;

	}



	pipe = usb_sndbulkpipe(dev->udev, dev->out_epAddr);

	usb_fill_bulk_urb(urb, dev->udev, pipe, data, size,

				diag_bridge_write_cb, dev);

	urb->transfer_flags |= URB_ZERO_PACKET;

	usb_anchor_urb(urb, &dev->submitted);

	dev->pending_writes++;



	ret = usb_submit_urb(urb, GFP_KERNEL);

	if (ret) {

		pr_err_ratelimited("submitting urb failed err:%d", ret);

		dev->pending_writes--;

		usb_unanchor_urb(urb);

		usb_autopm_put_interface(dev->ifc);

		goto free_error;

	}



free_error:

	usb_free_urb(urb);

put_error:

	if (ret) /* otherwise this is done in the completion handler */

		kref_put(&dev->kref, diag_bridge_delete);

error:

	mutex_unlock(&dev->ifc_mutex);

	return ret;

}

EXPORT_SYMBOL(diag_bridge_write);



#if defined(CONFIG_DEBUG_FS)

#define DEBUG_BUF_SIZE	512

static ssize_t diag_read_stats(struct file *file, char __user *ubuf,

				size_t count, loff_t *ppos)

{

	char			*buf;

	int			i, ret = 0;



	buf = kzalloc(sizeof(char) * DEBUG_BUF_SIZE, GFP_KERNEL);

	if (!buf)

		return -ENOMEM;



	for (i = 0; i < MAX_DIAG_BRIDGE_DEVS; i++) {

		struct diag_bridge *dev = __dev[i];



		if (!dev)

			continue;



		ret += scnprintf(buf, DEBUG_BUF_SIZE,

				"epin:%d, epout:%d\n"

				"bytes to host: %lu\n"

				"bytes to mdm: %lu\n"

				"pending reads: %u\n"

				"pending writes: %u\n"

				"drop count:%u\n"

				"last error: %d\n",

				dev->in_epAddr, dev->out_epAddr,

				dev->bytes_to_host, dev->bytes_to_mdm,

				dev->pending_reads, dev->pending_writes,

				dev->drop_count,

				dev->err);

	}



	ret = simple_read_from_buffer(ubuf, count, ppos, buf, ret);

	kfree(buf);

	return ret;

}



static ssize_t diag_reset_stats(struct file *file, const char __user *buf,

				 size_t count, loff_t *ppos)

{

	int i;



	for (i = 0; i < MAX_DIAG_BRIDGE_DEVS; i++) {

		struct diag_bridge *dev = __dev[i];



		if (dev) {

			dev->bytes_to_host = dev->bytes_to_mdm = 0;

			dev->pending_reads = dev->pending_writes = 0;

			dev->drop_count = 0;

		}

	}



	return count;

}



const struct file_operations diag_stats_ops = {

	.read = diag_read_stats,

	.write = diag_reset_stats,

};



static struct dentry *dent;



static void diag_bridge_debugfs_init(void)

{

	struct dentry *dfile;



	dent = debugfs_create_dir("diag_bridge", 0);

	if (IS_ERR(dent))

		return;



	dfile = debugfs_create_file("status", 0444, dent, 0, &diag_stats_ops);

	if (!dfile || IS_ERR(dfile))

		debugfs_remove(dent);

}



static void diag_bridge_debugfs_cleanup(void)

{

	debugfs_remove_recursive(dent);

	dent = NULL;

}

#else

static inline void diag_bridge_debugfs_init(void) { }

static inline void diag_bridge_debugfs_cleanup(void) { }

#endif



static int

diag_bridge_probe(struct usb_interface *ifc, const struct usb_device_id *id)

{

	struct diag_bridge		*dev;

	struct usb_host_interface	*ifc_desc;

	struct usb_endpoint_descriptor	*ep_desc;

	int				i, devid, ret = -ENOMEM;



	pr_debug("id:%lu", id->driver_info);



	devid = id->driver_info & 0xFF;

	if (devid < 0 || devid >= MAX_DIAG_BRIDGE_DEVS)

		return -ENODEV;



	/* already probed? */

	if (__dev[devid]) {

		pr_err("Diag device already probed");

		return -ENODEV;

	}



	dev = kzalloc(sizeof(*dev), GFP_KERNEL);

	if (!dev)

		return -ENOMEM;



	__dev[devid] = dev;

	dev->id = devid;



	dev->udev = usb_get_dev(interface_to_usbdev(ifc));

	dev->ifc = ifc;

	kref_init(&dev->kref);

	mutex_init(&dev->ifc_mutex);

	init_usb_anchor(&dev->submitted);



	ifc_desc = ifc->cur_altsetting;

	for (i = 0; i < ifc_desc->desc.bNumEndpoints; i++) {

		ep_desc = &ifc_desc->endpoint[i].desc;

		if (!dev->in_epAddr && (usb_endpoint_is_bulk_in(ep_desc) ||

			usb_endpoint_is_int_in(ep_desc))) {

			dev->in_epAddr = ep_desc->bEndpointAddress;

			if (usb_endpoint_is_int_in(ep_desc)) {

				dev->use_int_in_pipe = 1;

				dev->period = ep_desc->bInterval;

			}

		}

		if (!dev->out_epAddr && usb_endpoint_is_bulk_out(ep_desc))

			dev->out_epAddr = ep_desc->bEndpointAddress;

	}



	if (!(dev->in_epAddr && dev->out_epAddr)) {

		pr_err("could not find bulk in and bulk out endpoints");

		ret = -ENODEV;

		goto error;

	}



	usb_set_intfdata(ifc, dev);

	diag_bridge_debugfs_init();

	dev->pdev = platform_device_register_simple("diag_bridge", devid,

						    NULL, 0);

	if (IS_ERR(dev->pdev)) {

		pr_err("unable to allocate platform device");

		ret = PTR_ERR(dev->pdev);

		goto clean_debugfs;

	}



	dev_dbg(&dev->ifc->dev, "%s: complete\n", __func__);



	return 0;



clean_debugfs:

	diag_bridge_debugfs_cleanup();

error:

	if (dev)

		kref_put(&dev->kref, diag_bridge_delete);



	return ret;

}



static void diag_bridge_disconnect(struct usb_interface *ifc)

{

	struct diag_bridge	*dev = usb_get_intfdata(ifc);



	dev_dbg(&dev->ifc->dev, "%s:\n", __func__);



	platform_device_unregister(dev->pdev);

	mutex_lock(&dev->ifc_mutex);

	dev->ifc = NULL;

	mutex_unlock(&dev->ifc_mutex);

	diag_bridge_debugfs_cleanup();

	kref_put(&dev->kref, diag_bridge_delete);

	usb_set_intfdata(ifc, NULL);

}



static int diag_bridge_suspend(struct usb_interface *ifc, pm_message_t message)

{

	struct diag_bridge	*dev = usb_get_intfdata(ifc);

	struct diag_bridge_ops	*cbs = dev->ops;

	int ret = 0;



	if (cbs && cbs->suspend) {

		ret = cbs->suspend(cbs->ctxt);

		if (ret) {

			dev_dbg(&dev->ifc->dev,

				"%s: diag veto'd suspend\n", __func__);

			return ret;

		}



		usb_kill_anchored_urbs(&dev->submitted);

	}



	return ret;

}



static int diag_bridge_resume(struct usb_interface *ifc)

{

	struct diag_bridge	*dev = usb_get_intfdata(ifc);

	struct diag_bridge_ops	*cbs = dev->ops;





	if (cbs && cbs->resume)

		cbs->resume(cbs->ctxt);



	return 0;

}



#define DEV_ID(n)		(n)



static const struct usb_device_id diag_bridge_ids[] = {

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x9001, 0),

	.driver_info =  DEV_ID(0), },

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x9034, 0),

	.driver_info =  DEV_ID(0), },

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x9048, 0),

	.driver_info =  DEV_ID(0), },

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x904C, 0),

	.driver_info =  DEV_ID(0), },

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x9075, 0),

	.driver_info =  DEV_ID(0), },

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x9079, 0),

	.driver_info =  DEV_ID(1), },

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x908A, 0),

	.driver_info =  DEV_ID(0), },

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x908E, 0),

	.driver_info =  DEV_ID(0), },

	/* 908E, ifc#1 refers to diag client interface */

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x908E, 1),

	.driver_info =  DEV_ID(1), },

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x909C, 0),

	.driver_info =  DEV_ID(0), },

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x909D, 0),

	.driver_info =  DEV_ID(0), },

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x909E, 0),

	.driver_info =  DEV_ID(0), },

	/* 909E, ifc#1 refers to diag client interface */

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x909E, 1),

	.driver_info =  DEV_ID(1), },

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x909F, 0),

	.driver_info =	DEV_ID(0), },

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x90A0, 0),

	.driver_info =  DEV_ID(0), },

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x90A4, 0),

	.driver_info =	DEV_ID(0), },

	/* 909E, ifc#1 refers to diag client interface */

	{ USB_DEVICE_INTERFACE_NUMBER(0x5c6, 0x90A4, 1),

	.driver_info =	DEV_ID(1), },



	{} /* terminating entry */

};

MODULE_DEVICE_TABLE(usb, diag_bridge_ids);



static struct usb_driver diag_bridge_driver = {

	.name =		"diag_bridge",

	.probe =	diag_bridge_probe,

	.disconnect =	diag_bridge_disconnect,

	.suspend =	diag_bridge_suspend,

	.resume =	diag_bridge_resume,

	.reset_resume =	diag_bridge_resume,

	.id_table =	diag_bridge_ids,

	.supports_autosuspend = 1,

};



static int __init diag_bridge_init(void)

{

	int ret;



	ret = usb_register(&diag_bridge_driver);

	if (ret) {

		pr_err("unable to register diag driver");

		return ret;

	}



	return 0;

}



static void __exit diag_bridge_exit(void)

{

	usb_deregister(&diag_bridge_driver);

}



module_init(diag_bridge_init);

module_exit(diag_bridge_exit);



MODULE_DESCRIPTION(DRIVER_DESC);

MODULE_LICENSE("GPL v2");

include/linux/usb/diag_bridge.h

0 → 100644
+54 −0
Original line number Diff line number Diff line 
/* Copyright (c) 2011, 2013, 2018-2019, The Linux Foundation. All rights reserved.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 and

 * only version 2 as published by the Free Software Foundation.

 *

 * 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.

 */



#ifndef __LINUX_USB_DIAG_BRIDGE_H__

#define __LINUX_USB_DIAG_BRIDGE_H__



struct diag_bridge_ops {

	void *ctxt;

	void (*read_complete_cb)(void *ctxt, char *buf,

			int buf_size, int actual);

	void (*write_complete_cb)(void *ctxt, char *buf,

			int buf_size, int actual);

	int (*suspend)(void *ctxt);

	void (*resume)(void *ctxt);

};



#if IS_ENABLED(CONFIG_USB_QCOM_DIAG_BRIDGE)



extern int diag_bridge_read(int id, char *data, int size);

extern int diag_bridge_write(int id, char *data, int size);

extern int diag_bridge_open(int id, struct diag_bridge_ops *ops);

extern void diag_bridge_close(int id);



#else



static int __maybe_unused diag_bridge_read(int id, char *data, int size)

{

	return -ENODEV;

}



static int __maybe_unused diag_bridge_write(int id, char *data, int size)

{

	return -ENODEV;

}



static int __maybe_unused diag_bridge_open(int id, struct diag_bridge_ops *ops)

{

	return -ENODEV;

}



static void __maybe_unused diag_bridge_close(int id) { }



#endif



#endif