Hi Jean,
On Wed, 2010-09-08 at 15:06 -0400, Jean Delvare wrote:
> Hi Guenter,
>
> On Wed, 8 Sep 2010 08:35:00 -0700, Guenter Roeck wrote:
> > This patch adds support for max6695/96 to sensors-detect.
> >
> > ---
> > Index: prog/detect/sensors-detect
> > ===================================================================
> > --- prog/detect/sensors-detect (revision 5857)
> > +++ prog/detect/sensors-detect (working copy)
> > @@ -921,8 +921,13 @@
> > name => "Maxim MAX6680/MAX6681",
> > driver => "lm90",
> > i2c_addrs => [0x18..0x1a, 0x29..0x2b, 0x4c..0x4e],
> > - i2c_detect => sub { lm90_detect(@_, 7); },
> > + i2c_detect => sub { max6680_95_detect(@_, 0); },
> > }, {
> > + name => "Maxim MAX6695/MAX6696",
> > + driver => "lm90",
> > + i2c_addrs => [0x18..0x1a, 0x29..0x2b, 0x4c..0x4e],
> > + i2c_detect => sub { max6680_95_detect(@_, 1); },
> > + }, {
> > name => "Winbond W83L771W/G",
> > driver => "to-be-written",
> > i2c_addrs => [0x4c],
> > @@ -4051,10 +4056,46 @@
> > return $confidence;
> > }
> >
> > +# Chip to detect: 0 = MAX6680/81, 1 = MAX6695/96
> > +# Registers used:
> > +# 0x03: Configuration
> > +# 0x04: Conversion rate
> > +# 0x12: Status2
> > +# 0x16: Overtemperature 2
> > +# 0xfe: Manufacturer ID
> > +# 0xff: Chip ID / die revision
> > +sub max6680_95_detect
> > +{
> > + my ($file, $addr, $chip) = @_;
> > + my $mid = i2c_smbus_read_byte_data($file, 0xfe);
> > + my $cid = i2c_smbus_read_byte_data($file, 0xff);
> > + my $conf = i2c_smbus_read_byte_data($file, 0x03);
> > + my $rate = i2c_smbus_read_byte_data($file, 0x04);
> > + my $emerg = i2c_smbus_read_byte_data($file, 0x16);
> > + my $status2 = i2c_smbus_read_byte_data($file, 0x12);
> > +
> > + if ($chip == 0) {
> > + return if ($conf & 0x03) != 0;
> > + return if $rate > 0x07;
> > + return if $emerg != $rate;
>
> Please take a look at max6657_detect(). Obviously you assume that the
> SMBus read commands above were executed in a specific order, which
> isn't actually guaranteed, because sensors-detect has a register cache
> to speed up detection. You really want to pass NO_CACHE as a third
> parameter if you want to by-pass the cache and thus ensure that the
> read order is as desired.
>
Yes, I completely missed that.
> Also, as discussed before, comparing $emerg and $rate is likely to work
> in most cases, but isn't 100% reliable. You might want to consider the
> following sequence instead:
>
> my $mid = i2c_smbus_read_byte_data($file, 0xfe, NO_CACHE);
> my $emerg1 = i2c_smbus_read_byte_data($file, 0x16, NO_CACHE);
> my $rate = i2c_smbus_read_byte_data($file, 0x04, NO_CACHE);
> my $emerg2 = i2c_smbus_read_byte_data($file, 0x16, NO_CACHE);
>
> if ($emerg1 != $emerg2)
> # MAX6680/MAX6681
> else
> # MAX6695/MAX6696
>
> This is guaranteed to work because $mid and $rate can't have the same
> value.
Excellent idea. I'll try that.
>
>
> > + return if $mid != 0x4d; # Maxim
> > + return 8 if $cid == 0x01; # MAX6680/MAX6681
> > + }
> > + if ($chip == 1) {
> > + return if ($conf & 0x10) != 0;
> > + return if ($status2 & 0x01) != 0;
> > + return if $rate > 0x07;
> > + return if $emerg == $rate;
> > + return if $mid != 0x4d; # Maxim
> > + return 8 if $cid == 0x01; # MAX6695/MAX6696
> > + }
> > + return;
> > +}
> > +
> > # Chip to detect: 0 = LM90, 1 = LM89/LM99, 2 = LM86, 3 = ADM1032,
> > # 4 = MAX6654, 5 = ADT7461,
> > # 6 = MAX6646/MAX6647/MAX6648/MAX6649/MAX6692,
> > -# 7 = MAX6680/MAX6681, 8 = W83L771W/G, 9 = TMP401, 10 = TMP411,
> > +# 7 = unused, 8 = W83L771W/G, 9 = TMP401, 10 = TMP411,
> > # 11 = W83L771AWG/ASG, 12 = MAX6690
> > # Registers used:
> > # 0x03: Configuration
> > @@ -4116,10 +4157,7 @@
> > return 8 if $cid == 0x59; # MAX6648/MAX6692
> > }
> > if ($chip == 7) {
> > - return if ($conf & 0x03) != 0;
> > - return if $rate > 0x07;
> > - return if $mid != 0x4d; # Maxim
> > - return 8 if $cid == 0x01; # MAX6680/MAX6681
> > + return;
> > }
>
> Why not skip it altogether? And same for the comment above? These are
> arbitrary numbers, it's totally OK if they don't follow each other.
>
Ok.
Guenter
> > if ($chip == 8) {
> > return if ($conf & 0x2a) != 0;
>
>
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