[PATCH] Revert "serial: amba-pl011: fix incorrect integer size in pl011_fifo_to_tty()"

Peter Hurley peter at hurleysoftware.com
Fri Oct 23 10:49:06 PDT 2015


On 10/23/2015 12:38 PM, Timur Tabi wrote:
> On 10/23/2015 11:02 AM, Dave P Martin wrote:
>> I'm pretty sure CREAD should default to enabled[1], and that usually
>> software won't modify it.
>>
>> Assuming that this is indeed the problem, it's possible that another bug
>> in the pl011 driver is wrongly clearing this flag.  Sadly I don't have
>> time to look at the code again just now ...:(
> 
> Perhaps, but !CREAD is definitely broken without this patch.  So if the driver really is clearing CREAD somewhere else, then that's where the real bug is.
> 
>>
>> Could be interesting to stick some BUG_ON(!CREAD) in the driver to
>> try and track down where that's coming from.
> 
> CREAD is disabled by default when opening the console.  You need to explicitly set it in the termios structure.

No; the initial termios structure for all serial core-based drivers has
CREAD set:

pl011_probe
   pl011_register_port
      uart_register_driver
         ...
         normal->init_termios.c_cflag = .... | CREAD | ....;

Regards,
Peter Hurley



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