Hi,
On Thu, Jul 26, 2012 at 06:28:36PM +0800, Bhupesh SHARMA wrote:
> > I just doesn't work :-) Calling usb_gadget_disconnect() during bind
> > doesn't
> > prevent the device from being visible to the USB host. Bhupesh has
> > analyzed
> > the problem and submitted this RFC as a possible fix.
how about something like this instead:
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 3f72110..3390af2 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -1640,6 +1640,8 @@ int usb_composite_probe(struct usb_composite_driver *driver,
composite = driver;
composite_gadget_bind = bind;
+ composite_driver.controls_pullup = driver->controls_pullup;
+
return usb_gadget_probe_driver(&composite_driver, composite_bind);
}
diff --git a/drivers/usb/gadget/udc-core.c b/drivers/usb/gadget/udc-core.c
index e5e44f8..d8b4dc3 100644
--- a/drivers/usb/gadget/udc-core.c
+++ b/drivers/usb/gadget/udc-core.c
@@ -263,7 +263,10 @@ static void usb_gadget_remove_driver(struct usb_udc *udc)
if (udc_is_newstyle(udc)) {
udc->driver->disconnect(udc->gadget);
- usb_gadget_disconnect(udc->gadget);
+
+ if (!udc->driver->controls_pullup)
+ usb_gadget_disconnect(udc->gadget);
+
udc->driver->unbind(udc->gadget);
usb_gadget_udc_stop(udc->gadget, udc->driver);
} else {
@@ -347,7 +350,9 @@ found:
driver->unbind(udc->gadget);
goto err1;
}
- usb_gadget_connect(udc->gadget);
+
+ if (!driver->controls_pullup)
+ usb_gadget_connect(udc->gadget);
} else {
ret = usb_gadget_start(udc->gadget, driver, bind);
diff --git a/drivers/usb/gadget/webcam.c b/drivers/usb/gadget/webcam.c
index 120e134..1cfd951 100644
--- a/drivers/usb/gadget/webcam.c
+++ b/drivers/usb/gadget/webcam.c
@@ -396,6 +396,8 @@ static struct usb_composite_driver webcam_driver = {
.strings = webcam_device_strings,
.max_speed = USB_SPEED_SUPER,
.unbind = webcam_unbind,
+
+ .controls_pullup = true,
};
static int __init
diff --git a/include/linux/usb/composite.h b/include/linux/usb/composite.h
index 9d8c3b6..28326e5 100644
--- a/include/linux/usb/composite.h
+++ b/include/linux/usb/composite.h
@@ -262,6 +262,8 @@ void usb_remove_config(struct usb_composite_dev *,
* @max_speed: Highest speed the driver supports.
* @needs_serial: set to 1 if the gadget needs userspace to provide
* a serial number. If one is not provided, warning will be printed.
+ * @controls_pullup: this driver will control pullup and udc-core shouldn't
+ * enable it by default
* @unbind: Reverses bind; called as a side effect of unregistering
* this driver.
* @disconnect: optional driver disconnect method
@@ -290,6 +292,7 @@ struct usb_composite_driver {
struct usb_gadget_strings **strings;
enum usb_device_speed max_speed;
unsigned needs_serial:1;
+ unsigned controls_pullup:1;
int (*unbind)(struct usb_composite_dev *);
diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 9517466..eaa50ab 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -787,6 +787,7 @@ static inline int usb_gadget_disconnect(struct usb_gadget *gadget)
* @suspend: Invoked on USB suspend. May be called in_interrupt.
* @resume: Invoked on USB resume. May be called in_interrupt.
* @driver: Driver model state for this driver.
+ * @controls_pullup: tells udc-core to not enable pullups by default
*
* Devices are disabled till a gadget driver successfully bind()s, which
* means the driver will handle setup() requests needed to enumerate (and
@@ -844,6 +845,8 @@ struct usb_gadget_driver {
/* FIXME support safe rmmod */
struct device_driver driver;
+
+ unsigned controls_pullup:1;
};
All that's missing now is for uvc gadget to call
usb_function_activate/usb_function_deactivate() and the correct
locations. Make sure to call it from your ->disconnect() method as
udc-core won't do that for you by default.
> Yes. Felipe, plz go through the problem description as mentioned in the patch log
> message which can be seen here:
> http://permalink.gmane.org/gmane.linux.usb.general/66585
sure, please see above patch. The difference is that this has no impact
on the controller drivers.
--
balbi
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