commit c4ad974f3acef11e538e825ca0cb73be6faf2461
Author: David Fries <[EMAIL PROTECTED]>
Date: Sun Nov 4 18:14:21 2007 -0600
Corrected the decoding of negative C temperatures. The code did a binary
OR of two bytes to make a 16 bit value, but assignd it to an integer.
This caused the value to not be sign extended and to loose that it was a
negative number in the assignment.
Before the patch (in my freezer),
w1_slave
ed fe 4b 46 7f ff 03 10 e4 : crc=e4 YES
ed fe 4b 46 7f ff 03 10 e4 t=4078
With the patch,
e3 fe 4b 46 7f ff 0d 10 81 : crc=81 YES
e3 fe 4b 46 7f ff 0d 10 81 t=-17
diff --git a/drivers/w1/slaves/w1_therm.c b/drivers/w1/slaves/w1_therm.c
index 4318935..feed89e 100644
--- a/drivers/w1/slaves/w1_therm.c
+++ b/drivers/w1/slaves/w1_therm.c
@@ -112,7 +112,7 @@ static struct w1_therm_family_converter w1_therm_families[]
= {
static inline int w1_DS18B20_convert_temp(u8 rom[9])
{
- int t = (rom[1] << 8) | rom[0];
+ s16 t = (rom[1] << 8) | rom[0];
t /= 16;
return t;
}
--
David Fries <[EMAIL PROTECTED]>
http://fries.net/~david/ (PGP encryption key available)
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