usb: musb: Fix hub port setting for SPLIT transactions
The ifdef'ed Linux kernel code uses the 1 based port number, whereas U-Boot puts a 0 based port number into the register. The reason the 0 based port number apparently works can probably be taken from the USB 2.0 spec: 8.4.2.2 Start-Split Transaction Token ... The host must correctly set the port field for single and multiple TT hub implementations. A single TT hub implementation *may ignore* the port field. Actually, as far as I understand, a multi TT hub defaults to single TT (bAlternateSetting: 0) until switched via SetInterface, so even "port 42" would work. The change was verified by hardcoding the port number to a wrong value, SPLIT transactions kept working (although using a DWC2 instead of MUSB). Tested hubs are the RPi onboard SMC9514 and an external "05e3:0608 Genesys Logic, Inc. USB-2.0 4-Port HUB". The former is a multi TT hub, the latter single TT only. Addendum: Tested on sunxi/MUSB by Hans de Goede Signed-off-by: NStefan Brüns <stefan.bruens@rwth-aachen.de> Reviewed-by: NHans de Goede <hdegoede@redhat.com> Tested-by: NHans de Goede <hdegoede@redhat.com>
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