USB: gadget: composite: Add userspace notifications for USB state changes
Add switch to notify current USB configuration. This can be used to detect
USB connect and disconnect events.
Broadcast a change via the usb_composite class when a USB function is
enabled or disabled.
Rename usb_function.hidden to usb_function.disabled.
Signed-off-by: Mike Lockwood <lockwood@android.com>
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index fa785c6..e15c0b6 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -79,7 +79,7 @@
char *buf)
{
struct usb_function *f = dev_get_drvdata(dev);
- return sprintf(buf, "%d\n", !f->hidden);
+ return sprintf(buf, "%d\n", !f->disabled);
}
static ssize_t enable_store(
@@ -94,13 +94,18 @@
if (driver->enable_function)
driver->enable_function(f, value);
else
- f->hidden = !value;
+ usb_function_set_enabled(f, value);
return size;
}
static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR, enable_show, enable_store);
+void usb_function_set_enabled(struct usb_function *f, int enabled)
+{
+ f->disabled = !enabled;
+ kobject_uevent(&f->dev->kobj, KOBJ_CHANGE);
+}
/**
* usb_add_function() - add a function to a configuration
@@ -315,7 +320,7 @@
descriptors = f->hs_descriptors;
else
descriptors = f->descriptors;
- if (f->hidden || !descriptors || descriptors[0] == NULL)
+ if (f->disabled || !descriptors || descriptors[0] == NULL)
continue;
status = usb_descriptor_fillbuf(next, len,
(const struct usb_descriptor_header **) descriptors);
@@ -489,7 +494,7 @@
if (!f)
break;
- if (f->hidden)
+ if (f->disabled)
continue;
/*
@@ -539,6 +544,9 @@
power = c->bMaxPower ? (2 * c->bMaxPower) : CONFIG_USB_GADGET_VBUS_DRAW;
done:
usb_gadget_vbus_draw(gadget, power);
+
+ switch_set_state(&cdev->sdev, number);
+
if (result >= 0 && cdev->delayed_status)
result = USB_GADGET_DELAYED_STATUS;
return result;
@@ -1094,6 +1102,8 @@
if (composite->disconnect)
composite->disconnect(cdev);
spin_unlock_irqrestore(&cdev->lock, flags);
+
+ switch_set_state(&cdev->sdev, 0);
}
/*-------------------------------------------------------------------------*/
@@ -1154,6 +1164,7 @@
kfree(cdev->req->buf);
usb_ep_free_request(gadget->ep0, cdev->req);
}
+ switch_dev_unregister(&cdev->sdev);
device_remove_file(&gadget->dev, &dev_attr_suspended);
kfree(cdev);
set_gadget_data(gadget, NULL);
@@ -1222,6 +1233,11 @@
if (status < 0)
goto fail;
+ cdev->sdev.name = "usb_configuration";
+ status = switch_dev_register(&cdev->sdev);
+ if (status < 0)
+ goto fail;
+
cdev->desc = *composite->dev;
cdev->desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
@@ -1327,6 +1343,23 @@
cdev->suspended = 0;
}
+static int
+composite_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ struct usb_function *f = dev_get_drvdata(dev);
+
+ if (!f) {
+ /* this happens when the device is first created */
+ return 0;
+ }
+
+ if (add_uevent_var(env, "FUNCTION=%s", f->name))
+ return -ENOMEM;
+ if (add_uevent_var(env, "ENABLED=%d", !f->disabled))
+ return -ENOMEM;
+ return 0;
+}
+
/*-------------------------------------------------------------------------*/
static struct usb_gadget_driver composite_driver = {
@@ -1382,6 +1415,7 @@
driver->class = class_create(THIS_MODULE, "usb_composite");
if (IS_ERR(driver->class))
return PTR_ERR(driver->class);
+ driver->class->dev_uevent = composite_uevent;
return usb_gadget_probe_driver(&composite_driver, composite_bind);
}