Am Dienstag, den 20.08.2019, 22:18 +0000 schrieb
Charles.Hyde@xxxxxxxxxxxx:
> The core USB driver message.c is missing get/set address functionality
This should go into usbnet. The CDC parser is where it is because
it is needed for serial and network devices. As serial devices
do not have a MAC, this can go into usbnet.
> that stops ifconfig from being able to push MAC addresses out to USB
> based ethernet devices. Without this functionality, some USB devices
> stop responding to ethernet packets when using ifconfig to change MAC
> addresses. This has been tested with a Dell Universal Dock D6000.
>
> Signed-off-by: Charles Hyde <charles.hyde@xxxxxxxxxxxx>
> Cc: Mario Limonciello <mario.limonciello@xxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: linux-usb@xxxxxxxxxxxxxxx
> ---
> drivers/usb/core/message.c | 59 ++++++++++++++++++++++++++++++++++++++
> include/linux/usb.h | 3 ++
> 2 files changed, 62 insertions(+)
>
> diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
> index 5adf489428aa..eea775234b09 100644
> --- a/drivers/usb/core/message.c
> +++ b/drivers/usb/core/message.c
> @@ -1085,6 +1085,65 @@ int usb_clear_halt(struct usb_device *dev, int pipe)
> }
> EXPORT_SYMBOL_GPL(usb_clear_halt);
>
> +/**
> + * usb_get_address -
> + * @dev: device whose endpoint is halted
Which endpoint?
> + * @mac: buffer for containing
> + * Context: !in_interrupt ()
> + *
> + * This will attempt to get the six byte MAC address from a USB device's
> + * ethernet controller using GET_NET_ADDRESS command.
> + *
> + * This call is synchronous, and may not be used in an interrupt context.
> + *
> + * Return: Zero on success, or else the status code returned by the
Well, I am afraid it will return 6 on success.
> + * underlying usb_control_msg() call.
> + */
> +int usb_get_address(struct usb_device *dev, unsigned char * mac)
> +{
> + int ret = -ENOMEM;
Initialization is unnecessary here.
> + unsigned char *tbuf = kmalloc(256, GFP_NOIO);
If you intentionally picked a safety margin of 42 times, this
is cool. Otherwise it is a litttle much.
> +
> + if (!tbuf)
> + return -ENOMEM;
> +
> + ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
> + USB_CDC_GET_NET_ADDRESS,
> + USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
> + 0, USB_REQ_SET_ADDRESS, tbuf, 256,
> + USB_CTRL_GET_TIMEOUT);
> + if (ret == 6)
> + memcpy(mac, tbuf, 6);
You cannot ignore the case of devices sending more or less than 6
bytes.
Regards
Oliver
