#11 Patch to fix TIOCSERGETLSR bug (5.05)

[Ian Abbott]

This is a patch to fix a bug in serial-5.05.

The get_lsr_info() function used to get the result for
the TIOCSERGETLSR ioctl has a bug. The line that reads:

result &= TIOCSER_TEMT;

should read:

result |= TIOCSER_TEMT;

The effect of the bug is to render the second condition
for returning with the TIOCSER_TEMT bit set in the
result ineffective. (The first condition is checking if
the UART's transmitter is idle; the second condition is
checking if the UART's THR register is about to be
written.)

[Ian Abbott]

Serial 5.05 patch to fix TIOCSERGETLSR bug

[Ian Abbott]

Revised serial 5.05 patch to fix TIOCSERGETLSR bug

[Ian Abbott]

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Sorry, I mucked that up. The line should read as follows:

result &= ~TIOCSER_TEMT;

I.e. we want to clear the TIOCSER_TEMT bit in the result if
the second condition is true, NOT set it!