Le 24/08/2021 à 04:01, Fabio M. De Francesco a écrit :
On Tuesday, August 24, 2021 3:38:03 AM CEST Fabio M. De Francesco wrote:
I think that I've inadvertently switched the order by which usb_control_msg_send()
and memcpy() are called. I'm very sorry for not doing my tests, but (as I had said
before) at the moment I don't have my device with me.
No, I did not switch them. There must be something else...
Sorry for the noise.
Fabio
Hi,
'usb_control_msg_recv()' looks like:
int usb_control_msg_recv(struct usb_device *dev, __u8 endpoint, ...)
{
unsigned int pipe = usb_rcvctrlpipe(dev, endpoint);
...
ret = usb_control_msg(dev, pipe, ...);
'usb_control_msg()' looks like:
int usb_control_msg(struct usb_device *dev, unsigned int pipe, ...)
{
The difference is that one expect an 'endpoint' (and compute the pipe
from it), and the other expect a 'pipe'.
Also, in your code, 'pipe' looks un-initialized.
So, my guess is that you should rename 'pipe' into 'endpoint' (to keep
the semantic), have "endpoint = 0;" somewhere and pass it to
usb_control_msg_{recv|send}.
Or just remove 'pipe' and pass an explicit 0 directly.
Not sure it is enough, but it looks like a difference between before and
after your patch.
just my 2c,
CJ
