Re: [[RFC] 4/5] An LED "dimmer" trigger, which uses the PWM API to vary the brightness of an LED according to system load

[Trilok Soni <soni.trilok@gmail.com>]

Hi Luotao Fu,

On Fri, Oct 30, 2009 at 7:33 PM, Luotao Fu <l.fu@pengutronix.de> wrote:
> Hi,
>
> On Mon, Oct 19, 2009 at 08:42:36PM -0500, Bill Gatliff wrote:
>> Mike Frysinger wrote:
>> >On Mon, Oct 19, 2009 at 16:32, Bill Gatliff wrote:
>> >>--- a/drivers/leds/leds-pwm.c
>> >>+++ b/drivers/leds/leds-pwm.c
>> >>@@ -1,153 +1,167 @@
>> >>-/*
>> >>- * linux/drivers/leds-pwm.c
>> >>- *
>> >>- * simple PWM based LED control
>> >>- *
>> >>- * Copyright 2009 Luotao Fu @ Pengutronix (l.fu@pengutronix.de)
>> >>- *
>> >>- * based on leds-gpio.c by Raphael Assenat <raph@8d.com>
>> >>- *
>> >>- * This program is free software; you can redistribute it and/or modify
>> >>- * it under the terms of the GNU General Public License version 2 as
>> >>- * published by the Free Software Foundation.
>> >>- */
>> >
>> >this should not be removed.  if you wanted to add your copyright line,
>> >then that's fine, but the rest needs to stay.
>>
>> For the record, the reason the file looks like it does is because I
>> wrote an original one that replaced the previous leds-pwm.c--- but
>> obviously git didn't see it that way when it produced the diff.
>>
>> I certainly wasn't trying to write-out anyone's copyright!  I don't
>> have a problem with their names appearing in the file, regardless,
>> so I'll put them back in.  If they have problems with their names
>> appearing therein, they can let me know.  :)
>
> I certainly don't have any problems with that. ;-) As a matter of fact.
> My driver was a really simple spinoff of the gpio led driver. Nothing
> fancy in there. So I'm certainly happy that the driver will eventually
> see a rewrite. I'm just a little surprsied as I caught up this mail
> quite by occasion since I'm not subscribed to linux-embedded (time to do
> it now, I think ;-)). 'd be nice if you could put the copyright hint
> back in there. I'd test it by chance.
>
> The framework looks nice. The recent pwm stuff was more a loose policy
> and spreaded in different places in kernel. Nice to have a real frame
> work now. Nice work!

Your observation is correct, and that's why I prefer to have this
framework in mainline ASAP. It becomes more worst in the embedded
system, when you would like to share the device drivers in open-source
with different semiconductor vendor's SoCs. If you look at the Haptics
patches on LKML, you will observe this problem, and why we need to
have common PWM APIs in mainline.


-- 
---Trilok Soni
http://triloksoni.wordpress.com
http://www.linkedin.com/in/triloksoni