Return-Path: Received: from mail-pf0-f193.google.com ([209.85.192.193]:37801 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754332AbdIROoi (ORCPT ); Mon, 18 Sep 2017 10:44:38 -0400 Received: by mail-pf0-f193.google.com with SMTP id e69so269047pfg.4 for ; Mon, 18 Sep 2017 07:44:38 -0700 (PDT) Date: Mon, 18 Sep 2017 07:44:35 -0700 From: Guenter Roeck To: Patrick Venture Cc: joel@jms.id.au, kunyi@google.com, linux-hwmon@vger.kernel.org Subject: Re: [PATCH] hwmon: (aspeed-pwm-tacho) increase fan tach period Message-ID: <20170918144435.GA11868@roeck-us.net> References: <20170911224155.146738-1-venture@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170911224155.146738-1-venture@google.com> Sender: linux-hwmon-owner@vger.kernel.org List-Id: linux-hwmon@vger.kernel.org On Mon, Sep 11, 2017 at 03:41:55PM -0700, Patrick Venture wrote: > The previous value reduced the time required to determine > the fan value, however, it's also used as the final timeout > mechanism. The prevous value would work for any fan speed > greater than around 3k RPM. This increased value, lets the fan > speeds return quickly but will wait longer to handle speeds below 3k > RPM. > > Testing: this value was determined through experimentation on the ast2400 > on the Quanta-q71l. This configurations runs 8 fans attached to the > controller. > > Signed-off-by: Patrick Venture With reservations: Reviewed-by: Guenter Roeck This is the last time for me to accept a patch changing the value of M_TACH_UNIT in this driver. Any subsequent change will require a more comprehensive solution. Guenter > --- > drivers/hwmon/aspeed-pwm-tacho.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/hwmon/aspeed-pwm-tacho.c b/drivers/hwmon/aspeed-pwm-tacho.c > index 69b97d45e3cb..f914e5f41048 100644 > --- a/drivers/hwmon/aspeed-pwm-tacho.c > +++ b/drivers/hwmon/aspeed-pwm-tacho.c > @@ -161,7 +161,7 @@ > * 11: reserved. > */ > #define M_TACH_MODE 0x02 /* 10b */ > -#define M_TACH_UNIT 0x00c0 > +#define M_TACH_UNIT 0x0210 > #define INIT_FAN_CTRL 0xFF > > /* How long we sleep in us while waiting for an RPM result. */ > -- > 2.14.1.581.gf28d330327-goog > > -- > To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html