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Subject: Re: x86-power-control
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From: "Bills, Jason M" <jason.m.bills@linux.intel.com>
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Hi Oskar,

On 10/17/2019 10:21 AM, Oskar Senft wrote:
> Hi Jason
> 
> 
>     In our DTS we use gpio-line-names to name all of the GPIOs in one block:
> 
>     &gpio {
>              status = "okay";
>              gpio-line-names =
>     [...]
>              /*D0-D7*/       "","","","","","","","",
>              /*E0-E7*/     
>       "RESET_BUTTON","RESET_OUT","POWER_BUTTON","POWER_OUT","","","","",
>              /*F0-F7*/       "NMI_OUT","","","","CPU_ERR0","CPU_ERR1","","",
>              /*G0-G7*/     
>       "CPU_ERR2","CPU_CATERR","PCH_BMC_THERMTRIP","","","","","",
> 
> 
> Ugh, ok - that's a nice trick. But it's also a little messy :-/ Is that 
> the "officially recommended" way? I guess, since the other option I 
> tried doesn't work!.
I'm not completely sure.  I remember seeing this approach as an example 
when studying up on libgpiod and a quick search showed this approach 
used for other DTS files such as for Raspberry Pi 
(https://github.com/raspberrypi/linux/blob/e33ef2c4cd5dc96aa05a7d328eff61c183c94748/arch/arm/boot/dts/bcm2835-rpi-b-plus.dts#L37). 
  So, if not "officially recommended" it's at least not unheard of. :)

> 
> Is that purely used for naming lines, or does it have any semantic impact?
As far as I know, this is purely used for naming lines for libpiod and 
associated tools such as 'gpioinfo'.  You can still find and access GPIO 
lines by chip and line number.

> 
> Thanks
> Oskar.