Thread (4 messages) 4 messages, 2 authors, 2018-02-21

Re: [PATCH] ARM: dtc: tegra: enable front panel leds in TrimSlice

From: Stephen Warren <hidden>
Date: 2018-02-21 16:46:34
Also in: linux-arm-kernel, linux-devicetree, lkml

On 02/21/2018 09:20 AM, Tomasz Maciej Nowak wrote:
W dniu 20.02.2018 o 20:55, Stephen Warren pisze:
quoted
On 02/19/2018 01:16 PM, Tomasz Maciej Nowak wrote:
quoted
Adds device nodes for two front panel LEDs.
Why do you need to change the pinmux settings? Configuring a pin as a 
GPIO should override any pinmux special function selection and hence 
make it irrelevant, so I don't think you should need to change the 
pinmux.
At first I did exactly that without changing the pinmux, but the LEDs 
didn't light up. After that I compared with CompuLab source tree [1]. 
The pinmux was specified as in my patch. With this change the LEDs are 
fully functional.

1. 
https://gitorious.org/trimslice-kernel/trimslice-kernel?p=trimslice-kernel:trimslice-kernel.git;a=blob;f=arch/arm/mach-tegra/board-trimslice-pinmux.c;h=cc6d5225d97eb9327c820bf1d5b2bc16ab8c6dda;hb=d25bf45d6314089489b30d218ed8a0d6d94417f9#l45 
Oh I see. Your patch isn't changing the pinmux function selection but 
the other configuration bits, which are relevant even when the pin is in 
GPIO mode. In particular, it clears the tristate bit for the dte 
pingroup. That makes perfect sense.

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help