tps6598x error: failed to register partner

There is this error message when booting the Librem 5, and it appears again later on when the USB-C charging cable is plugged or unplugged.

Mar 09 10:35:40 pureos kernel: tps6598x 0-003f: failed to register partner

This happens in drivers/usb/typec/tps6598x.c in tps6598x_read_partner_identity when it fails to read identity info, it tries to read a number of bytes given by the size of the tps6598x_rx_identity_reg struct, but the number of bytes read is smaller than that.

Fixing this may be a step on the way towards solving https://source.puri.sm/Librem5/linux-next/-/issues/250 but it seems something else will be needed also.