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Coding bug in the function serial_ioport_write in serial.c
Branch hash: b50ea0d (pulled from github).
I was reviewing the code and noticed the following in the function serial_ioport_write:
assert(size == 1 && addr < 8);
.
.
.
switch(addr) {
default:
case 0:
if (s->lcf & UART_LCR_DLAB) {
if (size == 1) {
s->divider = (s->divider & 0xff00) | val;
} else {
s->divider = val;
}
}
The assert will trigger if the size is > 1, so the else of the if (size == 1) will never be executed and an attempt to specify a size > 1 will trigger an assert.
The documentation for the UART indicates that the 16-bit divisor is broken up amongst 2 8-bit registers (DLL and DLM). There already is code to handle the DLL and DLM portions of the divider register (as coded).
This is not exactly going to cause a bug, as there is no code that calls this function with a value for size other than 1. It is just unnecessary code.
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