On 13-12-16 05:17 AM, Linus Walleij wrote:
On Sat, Dec 14, 2013 at 2:16 AM, Sherman Yin <syin@xxxxxxxxxxxx> wrote:
+- bias-pull-up: Integer. Pull up strength in Ohm:
+ 1: 1.2 kOhm
+ 2: 1.8 kOhm
+ 3: 720 Ohm
+ 4: 2.7 kOhm
+ 5: 831 Ohm
+ 6: 1.08 kOhm
+ 7: 568 Ohm
Please do not use these custom enumerators 1 thru 7.
Instead say that the argument is given in ohms, so for
example:
bias-pull-up = <12000>;
Then translate this into the proper enumerator in your
driver instead.
Ok. The 3 bits in this enumeration correspond to enabling the 3 pull up Rs
(1.2k, 1.8k, 2.7k) in parallel, so the enum kind of make sense. But sure I
can change it to actual ohms and will error out in the driver if specified
value is not one of the 7.
Aha, that's how they do it :-)
Please write this in a comment in the driver because it makes
it a lot easier to understand what is going on, and e.g. how to
fuzz an apropriate resistance.
Yes, I plan to explain where those odd numbers come from in this file.
Can you tell me something about how such resistors are produced
in silicon?
Sorry I'm not quite sure. I only know a little bit of the circuitry
down to the schematic level...
Regards,
Sherman
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