Commit b0c13860 authored by Bjørn Mork's avatar Bjørn Mork Committed by Greg Kroah-Hartman
Browse files

usb: cdc-wdm: adding list lookup indirection 



Register all interfaces handled by this driver in a list, getting
rid of the dependency on usb_set_intfdata.  This allows further
generalization and simplification of the probe/create functions.

This is needed to decouple wdm_open from the driver owning the
interface, and it also allows us to share all the code in
wdm_create with drivers unable to do usb_set_intfdata.

Signed-off-by: default avatarBjørn Mork <bjorn@mork.no>
Acked-by: default avatarOliver Neukum <oneukum@suse.de>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 0dffb486

drivers/usb/class/cdc-wdm.c

+48 −12
Original line number Diff line number Diff line
@@ -78,6 +78,8 @@ MODULE_DEVICE_TABLE (usb, wdm_ids); 
#define WDM_DEFAULT_BUFSIZE	256



static DEFINE_MUTEX(wdm_mutex);

static DEFINE_SPINLOCK(wdm_device_list_lock);

static LIST_HEAD(wdm_device_list);



/* --- method tables --- */
@@ -112,10 +114,39 @@ struct wdm_device { 
	struct work_struct	rxwork;

	int			werr;

	int			rerr;



	struct list_head	device_list;

};



static struct usb_driver wdm_driver;



/* return intfdata if we own the interface, else look up intf in the list */

static struct wdm_device *wdm_find_device(struct usb_interface *intf)

{

	struct wdm_device *desc = NULL;



	spin_lock(&wdm_device_list_lock);

	list_for_each_entry(desc, &wdm_device_list, device_list)

		if (desc->intf == intf)

			break;

	spin_unlock(&wdm_device_list_lock);



	return desc;

}



static struct wdm_device *wdm_find_device_by_minor(int minor)

{

	struct wdm_device *desc = NULL;



	spin_lock(&wdm_device_list_lock);

	list_for_each_entry(desc, &wdm_device_list, device_list)

		if (desc->intf->minor == minor)

			break;

	spin_unlock(&wdm_device_list_lock);



	return desc;

}



/* --- callbacks --- */

static void wdm_out_callback(struct urb *urb)

{
@@ -275,6 +306,9 @@ static void free_urbs(struct wdm_device *desc) 


static void cleanup(struct wdm_device *desc)

{

	spin_lock(&wdm_device_list_lock);

	list_del(&desc->device_list);

	spin_unlock(&wdm_device_list_lock);

	kfree(desc->sbuf);

	kfree(desc->inbuf);

	kfree(desc->orq);
@@ -532,11 +566,11 @@ static int wdm_open(struct inode *inode, struct file *file) 
	struct wdm_device *desc;



	mutex_lock(&wdm_mutex);

	intf = usb_find_interface(&wdm_driver, minor);

	if (!intf)

	desc = wdm_find_device_by_minor(minor);

	if (!desc)

		goto out;



	desc = usb_get_intfdata(intf);

	intf = desc->intf;

	if (test_bit(WDM_DISCONNECTING, &desc->flags))

		goto out;

	file->private_data = desc;
@@ -639,6 +673,7 @@ static int wdm_create(struct usb_interface *intf, struct usb_endpoint_descriptor 
	desc = kzalloc(sizeof(struct wdm_device), GFP_KERNEL);

	if (!desc)

		goto out;

	INIT_LIST_HEAD(&desc->device_list);

	mutex_init(&desc->rlock);

	mutex_init(&desc->wlock);

	spin_lock_init(&desc->iuspin);
@@ -715,16 +750,17 @@ static int wdm_create(struct usb_interface *intf, struct usb_endpoint_descriptor 
		desc

	);



	usb_set_intfdata(intf, desc);

	spin_lock(&wdm_device_list_lock);

	list_add(&desc->device_list, &wdm_device_list);

	spin_unlock(&wdm_device_list_lock);



	rv = usb_register_dev(intf, &wdm_class);

	if (rv < 0)

		goto err2;

		goto err;

	else

		dev_info(&intf->dev, "%s: USB WDM device\n", dev_name(intf->usb_dev));

out:

	return rv;

err2:

	usb_set_intfdata(intf, NULL);

err:

	cleanup(desc);

	return rv;
@@ -785,8 +821,8 @@ static void wdm_disconnect(struct usb_interface *intf) 
	unsigned long flags;



	usb_deregister_dev(intf, &wdm_class);

	desc = wdm_find_device(intf);

	mutex_lock(&wdm_mutex);

	desc = usb_get_intfdata(intf);



	/* the spinlock makes sure no new urbs are generated in the callbacks */

	spin_lock_irqsave(&desc->iuspin, flags);
@@ -810,7 +846,7 @@ static void wdm_disconnect(struct usb_interface *intf) 
#ifdef CONFIG_PM

static int wdm_suspend(struct usb_interface *intf, pm_message_t message)

{

	struct wdm_device *desc = usb_get_intfdata(intf);

	struct wdm_device *desc = wdm_find_device(intf);

	int rv = 0;



	dev_dbg(&desc->intf->dev, "wdm%d_suspend\n", intf->minor);
@@ -860,7 +896,7 @@ static int recover_from_urb_loss(struct wdm_device *desc) 
#ifdef CONFIG_PM

static int wdm_resume(struct usb_interface *intf)

{

	struct wdm_device *desc = usb_get_intfdata(intf);

	struct wdm_device *desc = wdm_find_device(intf);

	int rv;



	dev_dbg(&desc->intf->dev, "wdm%d_resume\n", intf->minor);
@@ -874,7 +910,7 @@ static int wdm_resume(struct usb_interface *intf) 


static int wdm_pre_reset(struct usb_interface *intf)

{

	struct wdm_device *desc = usb_get_intfdata(intf);

	struct wdm_device *desc = wdm_find_device(intf);



	/*

	 * we notify everybody using poll of
@@ -898,7 +934,7 @@ static int wdm_pre_reset(struct usb_interface *intf) 


static int wdm_post_reset(struct usb_interface *intf)

{

	struct wdm_device *desc = usb_get_intfdata(intf);

	struct wdm_device *desc = wdm_find_device(intf);

	int rv;



	clear_bit(WDM_RESETTING, &desc->flags);

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