[U-Boot] hwmon init

[U-Boot] hwmon init

[Heiko Schocher]

Hello,

Is there a reason why the dtt sensors are initialized and accessed on
u-boot startup?

The U-Boot Design Principles[1] clearly say:

  Initialize devices only when they are needed within U-Boot, i.e. don't
  initialize the Ethernet interface(s) unless U-Boot performs a download
  over Ethernet; don't initialize any IDE or USB devices unless U-Boot
  actually tries to load files from these, etc. (and don't forget to
  shut down these devices after using them - otherwise nasty things may
  happen when you try to boot your OS).


Should that be changed?

bye,
Heiko

[1] http://www.denx.de/wiki/U-Boot/DesignPrinciples
-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany

[U-Boot] hwmon init

[Detlev Zundel]

Hello Heiko,

> Is there a reason why the dtt sensors are initialized and accessed on
> u-boot startup?

Historical reasons?

> The U-Boot Design Principles[1] clearly say:
>
>   Initialize devices only when they are needed within U-Boot, i.e. don't
>   initialize the Ethernet interface(s) unless U-Boot performs a download
>   over Ethernet; don't initialize any IDE or USB devices unless U-Boot
>   actually tries to load files from these, etc. (and don't forget to
>   shut down these devices after using them - otherwise nasty things may
>   happen when you try to boot your OS).
>
>
> Should that be changed?

Yes indeed, the current situation is not consistent with the design
principles and thus should be changed.  Patches welcome!

Best wishes
  Detlev

-- 
LISP is the most powerful programming language, and if you want an inter-
preter, LISP is the best.  None of the other languages come anywhere near
LISP in their power.  The most exciting things about LISP are read, eval,
and print.  If you look at other languages,  they have no equivalent for
any of those.                             -- Richard Stallman
--
DENX Software Engineering GmbH,      MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich,  Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-40 Fax: (+49)-8142-66989-80 Email: dzu at denx.de

[U-Boot] hwmon init

[Wolfgang Denk]

Dear Heiko Schocher,

In message <4D007F37.3010901@denx.de> you wrote:
> 
> Is there a reason why the dtt sensors are initialized and accessed on
> u-boot startup?

Someone once thought it was a good idea, and nobody fixed it since.

> Should that be changed?

Yes.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
All your people must learn before you can reach for the stars.
	-- Kirk, "The Gamesters of Triskelion", stardate 3259.2

[U-Boot] hwmon init

[Heiko Schocher]

Hello Wolfgang,

Wolfgang Denk wrote:
> Dear Heiko Schocher,
> 
> In message <4D007F37.3010901@denx.de> you wrote:
>> Is there a reason why the dtt sensors are initialized and accessed on
>> u-boot startup?
> 
> Someone once thought it was a good idea, and nobody fixed it since.
> 
>> Should that be changed?
> 
> Yes.

Ok, I prepare a patch.

bye,
Heiko
-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany