USB: g_mass_storage: thread_exits callback added

thread_exits callback has been added to fsg_common structure.
This callback is called when MSF's thread exits (is terminated
by a signal or function is unregistered).  It's then gadget's
responsibility to unregister the gadget.

Signed-off-by: Michal Nazarewicz <m.nazarewicz@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/gadget/f_mass_storage.c b/drivers/usb/gadget/f_mass_storage.c
index a6cec37768a9edbf4dd51345e86cb17383976930..a37640eba4344b144cc6d5747d155f55ec6f8239 100644 (file)
--- a/drivers/usb/gadget/f_mass_storage.c
+++ b/drivers/usb/gadget/f_mass_storage.c
@@ -367,6 +367,11 @@ struct fsg_common {
        struct completion       thread_notifier;
        struct task_struct      *thread_task;
 
+       /* Callback function to call when thread exits. */
+       void                    (*thread_exits)(struct fsg_common *common);
+       /* Gadget's private data. */
+       void                    *private_data;
+
        /* Vendor (8 chars), product (16 chars), release (4
         * hexadecimal digits) and NUL byte */
        char inquiry_string[8 + 16 + 4 + 1];
@@ -387,6 +392,11 @@ struct fsg_config {
        const char              *lun_name_format;
        const char              *thread_name;
 
+       /* Callback function to call when thread exits. */
+       void                    (*thread_exits)(struct fsg_common *common);
+       /* Gadget's private data. */
+       void                    *private_data;
+
        const char *vendor_name;                /*  8 characters or less */
        const char *product_name;               /* 16 characters or less */
        u16 release;
@@ -2605,11 +2615,8 @@ static int fsg_main_thread(void *common_)
        common->thread_task = NULL;
        spin_unlock_irq(&common->lock);
 
-       /* XXX */
-       /* If we are exiting because of a signal, unregister the
-        * gadget driver. */
-       /* if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags)) */
-       /*      usb_gadget_unregister_driver(&fsg_driver); */
+       if (common->thread_exits)
+               common->thread_exits(common);
 
        /* Let the unbind and cleanup routines know the thread has exited */
        complete_and_exit(&common->thread_notifier, 0);
@@ -2672,6 +2679,8 @@ static struct fsg_common *fsg_common_init(struct fsg_common *common,
                common->free_storage_on_release = 0;
        }
 
+       common->private_data = cfg->private_data;
+
        common->gadget = gadget;
        common->ep0 = gadget->ep0;
        common->ep0req = cdev->req;
@@ -2791,6 +2800,7 @@ static struct fsg_common *fsg_common_init(struct fsg_common *common,
 
 
        /* Tell the thread to start working */
+       common->thread_exits = cfg->thread_exits;
        common->thread_task =
                kthread_create(fsg_main_thread, common,
                               OR(cfg->thread_name, "file-storage"));
@@ -3057,6 +3067,9 @@ fsg_config_from_params(struct fsg_config *cfg,
        cfg->product_name = 0;
        cfg->release = 0xffff;
 
+       cfg->thread_exits = 0;
+       cfg->private_data = 0;
+
        /* Finalise */
        cfg->can_stall = params->stall;
 }

diff --git a/drivers/usb/gadget/mass_storage.c b/drivers/usb/gadget/mass_storage.c
index e43ca8f4be141fbf2e886ec2aec48d42e4fab734..19619fbf20ace5b4673520a2d0219996dc7f446f 100644 (file)
--- a/drivers/usb/gadget/mass_storage.c
+++ b/drivers/usb/gadget/mass_storage.c
@@ -132,9 +132,13 @@ static struct fsg_module_parameters mod_data = {
 };
 FSG_MODULE_PARAMETERS(/* no prefix */, mod_data);
 
+static unsigned long msg_registered = 0;
+static void msg_cleanup(void);
+
 static int __init msg_do_config(struct usb_configuration *c)
 {
        struct fsg_common *common;
+       struct fsg_config config;
        int ret;
 
        if (gadget_is_otg(c->cdev->gadget)) {
@@ -142,7 +146,9 @@ static int __init msg_do_config(struct usb_configuration *c)
                c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
        }
 
-       common = fsg_common_from_params(0, c->cdev, &mod_data);
+       fsg_config_from_params(&config, &mod_data);
+       config.thread_exits = (void(*)(struct fsg_common*))&msg_cleanup;
+       common = fsg_common_init(0, c->cdev, &config);
        if (IS_ERR(common))
                return PTR_ERR(common);
 
@@ -201,11 +207,7 @@ static int __init msg_bind(struct usb_composite_dev *cdev)
                return status;
 
        dev_info(&gadget->dev, DRIVER_DESC ", version: " DRIVER_VERSION "\n");
-       return 0;
-}
-
-static int __exit msg_unbind(struct usb_composite_dev *cdev)
-{
+       set_bit(0, &msg_registered);
        return 0;
 }
 
@@ -218,7 +220,6 @@ static struct usb_composite_driver msg_driver = {
        .dev            = &msg_device_desc,
        .strings        = dev_strings,
        .bind           = msg_bind,
-       .unbind         = __exit_p(msg_unbind),
 };
 
 MODULE_DESCRIPTION(DRIVER_DESC);
@@ -231,8 +232,9 @@ static int __init msg_init(void)
 }
 module_init(msg_init);
 
-static void __exit msg_cleanup(void)
+static void msg_cleanup(void)
 {
-       usb_composite_unregister(&msg_driver);
+       if (test_and_clear_bit(0, &msg_registered))
+               usb_composite_unregister(&msg_driver);
 }
 module_exit(msg_cleanup);