On Tue, Aug 20, 2019 at 10:18:42PM +0000, Charles.Hyde@xxxxxxxxxxxx wrote:
> The core USB driver message.c is missing get/set address functionality
> 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 -
trailing whitespace?
No description of what the function does?
> + * @dev: device whose endpoint is halted
> + * @mac: buffer for containing
Trailing whitespace?
> + * 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
> + * underlying usb_control_msg() call.
> + */
> +int usb_get_address(struct usb_device *dev, unsigned char * mac)
> +{
> + int ret = -ENOMEM;
> + unsigned char *tbuf = kmalloc(256, GFP_NOIO);
> +
> + 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);
> +
> + kfree(tbuf);
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(usb_get_address);
This is a VERY cdc-net-specific function. It is not a "generic" USB
function at all. Why does it belong in the USB core? Shouldn't it live
in the code that handles the other cdc-net-specific logic?
thanks,
greg k-h
