From mboxrd@z Thu Jan  1 00:00:00 1970
From: Guenter Roeck <guenter.roeck@ericsson.com>
Date: Fri, 18 Mar 2011 10:28:51 +0000
Subject: Re: [lm-sensors] Update on DS1721, DS1631, DS1631A, DS1731
Message-Id: <20110318102850.GA9484@ericsson.com>
List-Id: <lm-sensors.vger.kernel.org>
References: <20110318042048.GA8315@ericsson.com>
In-Reply-To: <20110318042048.GA8315@ericsson.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
To: lm-sensors@vger.kernel.org

Hi Jean,

On Fri, Mar 18, 2011 at 03:57:58AM -0400, Jean Delvare wrote:
> On Thu, 17 Mar 2011 21:20:48 -0700, Guenter Roeck wrote:
> > Hi all,
> >=20
> > I confirmed that DS1721, DS1631, DS1631A, and DS1731
> > work with the existing ds1621 driver:
> >=20
> > DS1721 (2x):
> > ds1621-i2c-5-48
> > Adapter: i2c-devantech-iss at bus 002 device 034
> > temp1:        +23.5=B0C  (low  =3D +10.0=B0C, high =3D +70.0=B0C)
> >=20
> > ds1621-i2c-5-49
> > Adapter: i2c-devantech-iss at bus 002 device 034
> > temp1:        +23.5=B0C  (low  =3D +10.0=B0C, high =3D +70.0=B0C)
> >=20
> > DS1631:
> > ds1621-i2c-5-4a
> > Adapter: i2c-devantech-iss at bus 002 device 034
> > temp1:        +23.0=B0C  (low  =3D +10.0=B0C, high =3D +70.0=B0C)
> >=20
> > DS1631A:
> > ds1621-i2c-5-4b
> > Adapter: i2c-devantech-iss at bus 002 device 034
> > temp1:        +23.0=B0C  (low  =3D +10.0=B0C, high =3D +70.0=B0C)
> >=20
> > DS1731:
> > ds1621-i2c-5-4c
> > Adapter: i2c-devantech-iss at bus 002 device 034
> > temp1:        +23.5=B0C  (low  =3D +10.0=B0C, high =3D +70.0=B0C)
> >=20
> > Output from sensors-detect:
> >=20
> > Driver `ds1621':
> >   * Bus `i2c-devantech-iss at bus 002 device 034'
> >     Busdriver `i2c_devantech_iss', I2C address 0x48
> >     Chip `Dallas Semiconductor DS1621/DS1631' (confidence: 3)
> >   * Bus `i2c-devantech-iss at bus 002 device 034'
> >     Busdriver `i2c_devantech_iss', I2C address 0x49
> >     Chip `Dallas Semiconductor DS1621/DS1631' (confidence: 3)
> >   * Bus `i2c-devantech-iss at bus 002 device 034'
> >     Busdriver `i2c_devantech_iss', I2C address 0x4a
> >     Chip `Dallas Semiconductor DS1621/DS1631' (confidence: 3)
> >   * Bus `i2c-devantech-iss at bus 002 device 034'
> >     Busdriver `i2c_devantech_iss', I2C address 0x4b
> >     Chip `Dallas Semiconductor DS1621/DS1631' (confidence: 3)
> >   * Bus `i2c-devantech-iss at bus 002 device 034'
> >     Busdriver `i2c_devantech_iss', I2C address 0x4c
> >     Chip `Dallas Semiconductor DS1621/DS1631' (confidence: 3)
> >=20
> > The chips still support register 0xee, even though that is not document=
ed
> > in the datasheets.
> >=20
> > Auto-detection and sensors-detect may or may not work depending
> > on chip configuration (it always works after power-up).
> > Explicit device instantiation always works.
> >=20
> > I'll update the list of supported devices to reflect this information.
>=20
> If memory serves, at least the DS1631 supports better resolution than
> the ds1621 driver currently offers. So claiming that it is supported
> isn't completely exact. What the driver supports is really the DS1621
> and the other chips happen to emulate it.
>=20
> It should really not be difficult to add proper support for all chips,
> I just could never find the time to look into it. The chips I have here
> are: one DS1621, two DS1631+ and two DS1624+.
>=20
Sure, can do that. What would you suggest ? Pick the best available resolut=
ion ?

Also, if we do that, I would use i2c_device_id to select the part, and not =
try
to auto-detect it. Another option would be to play with the configuration r=
egister=20
and try detecting chip types this way (ie set bit 3,4 and observe the resul=
t).=20
Not sure if that is a good idea, though. Any thoughts on this ?

Thanks,
Guenter

_______________________________________________
lm-sensors mailing list
lm-sensors@lm-sensors.org
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors