public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
* dts: n900: isp1704 gpio
@ 2014-11-27 14:13 Pali Rohár
  2014-11-27 15:22 ` Felipe Balbi
  0 siblings, 1 reply; 2+ messages in thread
From: Pali Rohár @ 2014-11-27 14:13 UTC (permalink / raw)
  To: Sebastian Reichel, Benoit Cousson, Pavel Machek, Ivaylo Dimitrov,
	Tony Lindgren, Aaro Koskinen, linux-omap, linux-kernel

[-- Attachment #1: Type: Text/Plain, Size: 514 bytes --]

Hello,

in commit "ARM: dts: OMAP3-N900: Add isp1704 support" 
e17337a26962943c27124a14b0794eabe76af437 was added support for 
isp1704 chip with configured gpio "3". Now I looked into legacy 
board rx51 data and there is gpio "67" for isp1704.

I would like to ask, why we have different gpio in board data and 
in DTS data? I'm sure that isp1704 worked from legacy board data 
without problem, so I do not understand why in DTS code is 
different gpio number.

-- 
Pali Rohár
pali.rohar@gmail.com

[-- Attachment #2: This is a digitally signed message part. --]
[-- Type: application/pgp-signature, Size: 198 bytes --]

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: dts: n900: isp1704 gpio
  2014-11-27 14:13 dts: n900: isp1704 gpio Pali Rohár
@ 2014-11-27 15:22 ` Felipe Balbi
  0 siblings, 0 replies; 2+ messages in thread
From: Felipe Balbi @ 2014-11-27 15:22 UTC (permalink / raw)
  To: Pali Rohár
  Cc: Sebastian Reichel, Benoit Cousson, Pavel Machek, Ivaylo Dimitrov,
	Tony Lindgren, Aaro Koskinen, linux-omap, linux-kernel

[-- Attachment #1: Type: text/plain, Size: 886 bytes --]

Hi,

On Thu, Nov 27, 2014 at 03:13:43PM +0100, Pali Rohár wrote:
> Hello,
> 
> in commit "ARM: dts: OMAP3-N900: Add isp1704 support" 
> e17337a26962943c27124a14b0794eabe76af437 was added support for 
> isp1704 chip with configured gpio "3". Now I looked into legacy 
> board rx51 data and there is gpio "67" for isp1704.
> 
> I would like to ask, why we have different gpio in board data and 
> in DTS data? I'm sure that isp1704 worked from legacy board data 
> without problem, so I do not understand why in DTS code is 
> different gpio number.

it's magic! Seriously though, each GPIO bank as 32 GPIOs with numbers
starting at 0, note that DTS uses the 3rd GPIO line on the 3rd GPIO
bank.

Bank0 handles GPIOs 0 - 31, Bank1 handles GPIOs 32 - 63, Bank 2 handles
GPIOs 64 - 95, and so on...

Offset 3 on Bank 3 would be 64 + 3 == 67. Yay, magic.

-- 
balbi

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2014-11-27 15:22 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2014-11-27 14:13 dts: n900: isp1704 gpio Pali Rohár
2014-11-27 15:22 ` Felipe Balbi

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox