[PATCH v3 2/2] usb: gadget: udc: Handle gadget_connect failure during bind operation

From: Krishna Kurapati
Date: Wed May 10 2023 - 03:54:03 EST


In the event, gadget_connect call (which invokes pullup) fails,
propagate the error to udc bind operation which inturn sends the
error to configfs. The userspace can then retry enumeartion if
it chooses to.

Signed-off-by: Krishna Kurapati <quic_kriskura@xxxxxxxxxxx>
Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
---
changes in v3: Rebase on top of usb-next

drivers/usb/gadget/udc/core.c | 21 +++++++++++++++++----
1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c
index 4641153e9706..69041cca5d24 100644
--- a/drivers/usb/gadget/udc/core.c
+++ b/drivers/usb/gadget/udc/core.c
@@ -1122,12 +1122,16 @@ EXPORT_SYMBOL_GPL(usb_gadget_set_state);
/* ------------------------------------------------------------------------- */

/* Acquire connect_lock before calling this function. */
-static void usb_udc_connect_control_locked(struct usb_udc *udc) __must_hold(&udc->connect_lock)
+static int usb_udc_connect_control_locked(struct usb_udc *udc) __must_hold(&udc->connect_lock)
{
+ int ret;
+
if (udc->vbus && udc->started)
- usb_gadget_connect_locked(udc->gadget);
+ ret = usb_gadget_connect_locked(udc->gadget);
else
- usb_gadget_disconnect_locked(udc->gadget);
+ ret = usb_gadget_disconnect_locked(udc->gadget);
+
+ return ret;
}

/**
@@ -1583,12 +1587,21 @@ static int gadget_bind_driver(struct device *dev)
goto err_start;
}
usb_gadget_enable_async_callbacks(udc);
- usb_udc_connect_control_locked(udc);
+ ret = usb_udc_connect_control_locked(udc);
+ if (ret)
+ goto err_connect_control;
+
mutex_unlock(&udc->connect_lock);

kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
return 0;

+ err_connect_control:
+ usb_gadget_disable_async_callbacks(udc);
+ if (gadget->irq)
+ synchronize_irq(gadget->irq);
+ usb_gadget_udc_stop_locked(udc);
+
err_start:
driver->unbind(udc->gadget);

--
2.40.0