From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from bh-25.webhostbox.net ([208.91.199.152]:35630 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756378AbcHDNZh (ORCPT ); Thu, 4 Aug 2016 09:25:37 -0400 Subject: Re: [PATCH] hwmon: (nct6775) Do not accept force_id unless chip is found To: Jean Delvare References: <1470287737-1212-1-git-send-email-linux@roeck-us.net> <20160804130048.5a33f1fb@endymion> Cc: Hardware Monitoring From: Guenter Roeck Message-ID: <57A341FB.2090308@roeck-us.net> Date: Thu, 4 Aug 2016 06:24:11 -0700 MIME-Version: 1.0 In-Reply-To: <20160804130048.5a33f1fb@endymion> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-hwmon-owner@vger.kernel.org List-Id: linux-hwmon@vger.kernel.org On 08/04/2016 04:00 AM, Jean Delvare wrote: > Hi Guenter, > > On Wed, 3 Aug 2016 22:15:37 -0700, Guenter Roeck wrote: >> Since commit 698a7c24a544 ("hwmon: (nct6775) Support two SuperIO chips >> in the same system"), the driver supports two Super-IO chips. This has >> the undesirable side effect that force_id always detects a second chip >> at address 0xfff8, even if no chip exists at that address. >> >> nct6775: Found NCT6793D or compatible chip at 0x4e:0xfff8 >> >> If no chip at all is found at a given SIO address, it does not make sense >> to instantiate it. Limit force_id to only work if some chip is found, >> that is if the chip ID returns a value other than 0xffff. > > Agreed, good catch. > >> >> Signed-off-by: Guenter Roeck >> --- >> drivers/hwmon/nct6775.c | 8 ++++---- >> 1 file changed, 4 insertions(+), 4 deletions(-) >> >> diff --git a/drivers/hwmon/nct6775.c b/drivers/hwmon/nct6775.c >> index d087a8e00cf5..7859a30ce31e 100644 >> --- a/drivers/hwmon/nct6775.c >> +++ b/drivers/hwmon/nct6775.c >> @@ -4232,11 +4232,11 @@ static int __init nct6775_find(int sioaddr, struct nct6775_sio_data *sio_data) >> if (err) >> return err; >> >> - if (force_id) >> + val = (superio_inb(sioaddr, SIO_REG_DEVID) << 8) | >> + superio_inb(sioaddr, SIO_REG_DEVID + 1); >> + if (force_id && val != 0xffff) >> val = force_id; >> - else >> - val = (superio_inb(sioaddr, SIO_REG_DEVID) << 8) >> - | superio_inb(sioaddr, SIO_REG_DEVID + 1); >> + >> switch (val & SIO_ID_MASK) { >> case SIO_NCT6106_ID: >> sio_data->kind = nct6106; > > Reviewed-by: Jean Delvare > Thanks! Guenter