Previously, the function would always return the max_len parameter.
This poses two issues:
1. the API requires to return the actual packet size
2. the API requires that if the packet is larger than max_len, the
packet is flushed and -ENOBUFS is returned
3. this basically bypasses the packet flushing, consequtive _recv()
would return the last packet again
This commit fixes those issues.
This changes the prefixes of the symbols generated from USEMODULE and
USEPKG variables. The changes are as follow:
KCONFIG_MODULE_ => KCONFIG_USEMODULE_
KCONFIG_PKG_ => KCONFIG_USEPKG_
MODULE_ => USEMODULE_
PKG_ => USEPKG_
The private parts need USB definitions (and are thus preferably used
from USB_H_USER_IS_RIOT_INTERNAL compilation units). Functions like
usb_board_reset_in_bootloader do not depend on USB headers for their
definitions and are fair game throughout the application even for
generic RIOT USB devices.
This adds an early exit when the usb interface with the data endpoints
is not activated. This prevents the cdc_ecm_netdev code from attempting
to send the PDU when the USB device is not yet initialized or activated
by a host.
The OUT endpoint of the cdc ecm data endpoint is only expected to
receive data when the alternative interface is activated. Signalling
ready in the init function can cause issues as the endpoints are not yet
enabled in the low level USB peripheral driver.
This commit changes the name of the requests over the control endpoints
to control requests instead of setup requests. This is a terminology fix
to follow the USB specification more closely as technically only the
first stage of a control request is named setup which contains a setup
packet. The whole transfer is a control transfer.
