[U-Boot] [PATCH 3/6] serial: Reorder serial_assign()

Simon Glass
2012-10-25T21:02:55Z

Hi,

On Thu, Oct 25, 2012 at 12:03 PM, Marek Vasut <marex@denx.de> wrote:
> Dear Simon Glass,
>
>> Hi,
>>
>> On Mon, Oct 22, 2012 at 10:23 AM, Allen Martin <amartin@nvidia.com> wrote:
>> > On Sat, Oct 20, 2012 at 01:19:00AM -0700, Marek Vasut wrote:
>> >> Dear Allen Martin,
>> >>
>> >> [...]
>> >>
>> >> > Hi Marek, the change to return value here broke serial output on
>> >> > tegra. What I see is that the serial device name (s->name) is
>> >> > "eserial0" as set by serial_ns16550.c, and the name passed in from the
>> >> > stdout environment is "serial" so they don't match and it fails. This
>> >> > always used to be ok because the return code didn't indicate failure
>> >> > and iomux_doenv() would continue on happily, but now it causes
>> >> > iomux_doenv() to fail and no printfs() work after that.
>> >> >
>> >> > Not sure what the right fix is, should stdout really be set to
>> >> > "eserial0"? It seems "serial" should mean "the default serial device"
>> >> > which for the normal case is the one and only device.
>> >>
>> >> Looking at the source, the obvious course of action is to fix iomux.c .
>> >
>> > I've been looking at this call to serial_assign() from iomux.c and I'm
>> > not convinced this code does anything meaningful at all. It passes
>> > the name of a struct stdio_dev device which serial_assign() then tries
>> > to match against the registered struct serial_devices, which will
>> > never match.
>> >
>> > What I don't understand is the case where you have a board that
>> > actually has more than one physical serial port and how the mapping
>> > from stdio_dev to serial_device happens.
>> >
>> > Also, looking at the code to cmd_nvedit, I think your change also broke
>> > "setenv stdout" for boards that don't define CONFIG_CONSOLE_MUX. We
>> > always have this on for tegra, so we don't go down this code path, but
>> > it looks identical to the code in iomux.c
>>
>> Sorry if I missed it - what was the resolution here? Should we revert
>> that change?
>
> Definitelly not. We should fix the iomux.c , possibly by flipping the inequation
> mark as a short term solution.

OK that's fine. Is someone working on a patch?

Regards,
Simon

>
> Best regards,
> Marek Vasut