From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean Delvare Date: Mon, 20 May 2013 12:15:25 +0000 Subject: [lm-sensors] sensors-detect:: Drop detection of DS1621-like chips Message-Id: <20130520141525.59931252@endymion.delvare> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lm-sensors@vger.kernel.org Detection of the Dallas/Maxim DS1621, DS1625 and DS1631 chips is weak and likely to result in false positives. There's no rationale for keeping it in sensors-detect as these chips are not found in desktop computer systems. So drop detection of these chips altogether. --- prog/detect/sensors-detect | 46 --------------------------------------------- 1 file changed, 46 deletions(-) --- lm-sensors.orig/prog/detect/sensors-detect 2013-05-20 13:25:33.992641174 +0200 +++ lm-sensors/prog/detect/sensors-detect 2013-05-20 14:11:21.668063379 +0200 @@ -803,11 +803,6 @@ use vars qw(@i2c_adapter_names); i2c_addrs => [0x2c..0x2f], i2c_detect => sub { adm9240_detect(@_, 0); }, }, { - name => "Dallas Semiconductor DS1621/DS1631", - driver => "ds1621", - i2c_addrs => [0x48..0x4f], - i2c_detect => sub { ds1621_detect(@_); }, - }, { name => "Dallas Semiconductor DS1780", driver => "adm9240", i2c_addrs => [0x2c..0x2f], @@ -4357,47 +4352,6 @@ sub lm92_detect return ($chip = 0) ? 4 : 2; } -# Registers used: -# 0xAA: Temperature -# 0xA1: High limit -# 0xA2: Low limit -# 0xA8: Counter -# 0xA9: Slope -# 0xAC: Configuration -# Detection is weak. We check if bit 4 (NVB) is clear, because it is -# unlikely to be set (would mean that EEPROM is currently being accessed). -# We also check the value of the counter and slope registers, the datasheet -# doesn't mention the possible values but the conversion formula together -# with experimental evidence suggest possible sanity checks. -# Not all devices enjoy SMBus read word transactions, so we do as much as -# possible with read byte transactions first, and only use read word -# transactions second. -sub ds1621_detect -{ - my ($file, $addr) = @_; - - my $conf = i2c_smbus_read_byte_data($file, 0xAC); - return if ($conf & 0x10); - - my $temp = i2c_smbus_read_word_data($file, 0xAA); - return if $temp < 0 || ($temp & 0x0f00); - # On the DS1631, the following two checks are too strict in theory, - # but in practice I very much doubt that anyone will set temperature - # limits not a multiple of 0.5 degrees C. - my $high = i2c_smbus_read_word_data($file, 0xA1); - return if $high < 0 || ($high & 0x7f00); - my $low = i2c_smbus_read_word_data($file, 0xA2); - return if $low < 0 || ($low & 0x7f00); - - return if ($temp = 0 && $high = 0 && $low = 0 && $conf = 0); - - # Old versions of the DS1621 apparently don't have the counter and - # slope registers (or they return crap) - my $counter = i2c_smbus_read_byte_data($file, 0xA8); - my $slope = i2c_smbus_read_byte_data($file, 0xA9); - return ($slope = 0x10 && $counter <= $slope) ? 3 : 2; -} - # Chip to detect: 0 = LM80, 1 = LM96080 # Registers used: # 0x00: Configuration register -- Jean Delvare _______________________________________________ lm-sensors mailing list lm-sensors@lm-sensors.org http://lists.lm-sensors.org/mailman/listinfo/lm-sensors