linux-mips
[Top] [All Lists]

Re: [PATCH v8 5/8] Loongson: YeeLoong: add hardware monitoring driver

To: Pavel Machek <pavel@ucw.cz>
Subject: Re: [PATCH v8 5/8] Loongson: YeeLoong: add hardware monitoring driver
From: Wu Zhangjin <wuzhangjin@gmail.com>
Date: Mon, 07 Dec 2009 17:41:10 +0800
Cc: Ralf Baechle <ralf@linux-mips.org>, akpm@linux-foundation.org, linux-mips@linux-mips.org, linux-kernel@vger.kernel.org, Dmitry Torokhov <dmitry.torokhov@gmail.com>, "Rafael J . Wysocki" <rjw@sisk.pl>, zhangfx@lemote.com, linux-laptop@vger.kernel.org, Stephen Rothwell <sfr@canb.auug.org.au>
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:subject:from:reply-to:to:cc :in-reply-to:references:content-type:organization:date:message-id :mime-version:x-mailer:content-transfer-encoding; bh=iueJ1ZW90iKbeFUGWAPugb/6njng6PWnLl9laIu155A=; b=wq44n3qQQ0JoGWw8fDiKXwriH9TLrrqLRqo5MfbpKW0238mC2cZgn23QKQVdS23SIN 8rOsOgnfyMB+p9DzJWoanZlLrGBGS5FjWWo56TE2rmaL78DaK/9ZgNUvsoeqFIyODE62 UI5zWim8MkzCx9633mMO3Cw1FpT87AaTJW30c=
Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:reply-to:to:cc:in-reply-to:references:content-type :organization:date:message-id:mime-version:x-mailer :content-transfer-encoding; b=H6FQwCvgvdQVIp3vxc3nqFCFO98BG1sYujLquQqpLeCoQUn/+MaIIj6nQN14dlY6nf iIPn1kGE6Pe4trvKp87bfGrzM/2wyifvOorxRsItmms097aiKuzE+z3Ih30YgFOg6ZuM dq7KXM/w9EUCLOZ2PzqeM1iQYLWfnxkZXrdJY=
In-reply-to: <20091207080446.GB23088@elf.ucw.cz>
Organization: DSLab, Lanzhou University, China
Original-recipient: rfc822;linux-mips@linux-mips.org
References: <cover.1260082252.git.wuzhangjin@gmail.com> <d8789fa7e97d8a170c4e2516d7ef2d2fbbe42cc6.1260082252.git.wuzhangjin@gmail.com> <20091206084717.GD2766@ucw.cz> <1260147298.3126.2.camel@falcon.domain.org> <20091207080446.GB23088@elf.ucw.cz>
Reply-to: wuzhangjin@gmail.com
Sender: linux-mips-bounce@linux-mips.org
On Mon, 2009-12-07 at 09:04 +0100, Pavel Machek wrote:
> > > What is going on here? I thought the value is already in two's
> > > complement... Is the above equivalent of
> > > 
> > >         if (value < 0)
> > >            value = -value; 
> > > 
> > > ? If so, why? If not, can you add a comment?
> > 
> > Right, then, will use this instead:
> > 
> > static int get_battery_current(void)
> > { 
> >     s16 value;
> > 
> >     value = (ec_read(REG_BAT_CURRENT_HIGH) << 8) |
> >             (ec_read(REG_BAT_CURRENT_LOW));
> > 
> >     return abs(value);
> > }
> 
> That's certainly better. But... why not return signed value? Current
> flowing from the battery is certainly very different from current
> flowing into it...

You are totally right ;)

Just test it, when flowing from the battery, the value is negative, and
when flowing into the battery, the value is positive, so, no abs()
needed. thanks!

BTW: This part of source code was written by another EC guy, not checked
it carefully, sorry ;)

Best Regards,
        Wu Zhangjin


<Prev in Thread] Current Thread [Next in Thread>