[PATCH] Handle reg-shift property for of_serial ports

Segher Boessenkool segher at kernel.crashing.org
Sun Jul 8 08:21:19 EST 2007

>> Can we add properties to indicate the common high-speed modes too?  
>> The
>> Natsemi baud-base thing could be autodetected by 8250.c if you'd  
>> let it,
>> but the SMSC trick just has to be set as a UPF_MAGIC_MULTIPLIER flag.
> Yes, that sounds good. I do not have enough understanding about the
> extra feature to know which ones should get detected with their own
> property, so I left that out for the next person that needs it...

Since these devices will work (just not with the extra-high
baudrates) when driven as a "standard" 16550, you can indeed
just add a property to declare the device supports this stuff.

But please also declare the device to be such a special device
in its "compatible" property.  So you end up with something like

	serial at i3f8
		reg = <1 3f8>;
		device_type = "serial";
		compatible = "smsc,12345", "ns16550a", "pnpPNP,501";
		clock-frequency = 1843200;
		smsc-multipliers; # <--- there's the new thing


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