The p and P packets are
implemented respectively by
rsp_read_reg ()
and
rsp_write_reg ()
.
These functions are very similar in implementation to
rsp_read_all_regs ()
and
rsp_write_all_regs ()
(see Section 4.7.6).
The two differences are that the packet data must be parsed to identify the register affected, and (clearly) only one register is read or written.