Good Morning Jean, On Mon, Sep 15, 2008 at 11:50:51PM +0200, Jean Delvare wrote: > Hi Manuel, > > Le lundi 15 septembre 2008, Manuel Lauss a ?crit?: > > Driver for the Texas Instruments TMP121/TMP123 SPI temperature sensors. > > The code is 99% identical to the LM70 driver; only the formula to > > calculate the temperature (in 1/1000 deg celsius) has been adjusted. > > > > Signed-off-by: Manuel Lauss <mano at roarinelk.homelinux.net> > > --- > > drivers/hwmon/Kconfig | 10 +++ > > drivers/hwmon/Makefile | 1 + > > drivers/hwmon/tmp121.c | 168 ++++++++++++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 179 insertions(+), 0 deletions(-) > > create mode 100644 drivers/hwmon/tmp121.c > > Wouldn't it make more sense to just add support for the TMP121/TMP123 > chips to the lm70 driver? Duplicating code is better avoided when > possible. Thankfully these drivers are relatively small, but still... I can do that, sure. New patch in the works. > > --- /dev/null > > +++ b/drivers/hwmon/tmp121.c > > (...) > > + /* > > + * The "raw" temperature read into rxbuf[] is a 16-bit signed 2's > > + * complement value. Only the MSB 13 bits (1 sign + 12 temperature > > + * bits) are meaningful; the LSB 3 bits are to be discarded. > > + * Each bit represents 0.0625 degrees Celsius. > > + */ > > + val = (raw * 625) / 80; > > This does not actually discard the 3 LSB. In order to do that, you > would need to write the following: > > val = (raw / 8) * 625 / 10; Don't drink and code... (the lower 3 bits read back as zero, so I used the cheap equation). Thank you! Manuel Lauss
