Hi Darrick, Back in April 2008, Paulius Zaleckas posted a patch fixing the voltage conversion routines of the adt7473 hwmon driver [1]. I reviewed it and asked for a cleaned up version [2] but Paulius never replied and the patch was lost. Still, I think this was a good patch so I just did the cleanup work and am going to push the patch to Linus in the next days. Can you please review and ack the patch below? I tested it on an emulated chip and it seems to work fine. Thanks. [1] http://lists.lm-sensors.org/pipermail/lm-sensors/2008-April/022942.html [2] http://lists.lm-sensors.org/pipermail/lm-sensors/2008-April/022972.html * * * * * Fix voltage conversion routines. Based on an earlier patch from Paulius Zaleckas. According to the datasheet voltage is scaled with resistors and value 192 is nominal voltage. 0 is 0V. Signed-off-by: Jean Delvare <khali at linux-fr.org> Cc: Paulius Zaleckas <paulius.zaleckas at teltonika.lt> Cc: Darrick J. Wong <djwong at us.ibm.com> --- drivers/hwmon/adt7473.c | 29 +++++++++-------------------- 1 file changed, 9 insertions(+), 20 deletions(-) --- linux-2.6.28-rc0.orig/drivers/hwmon/adt7473.c 2008-10-10 09:27:55.000000000 +0200 +++ linux-2.6.28-rc0/drivers/hwmon/adt7473.c 2008-10-21 14:38:29.000000000 +0200 @@ -319,35 +319,24 @@ out: } /* - * On this chip, voltages are given as a count of steps between a minimum - * and maximum voltage, not a direct voltage. + * Conversions */ -static const int volt_convert_table[][2] = { - {2997, 3}, - {4395, 4}, + +/* IN are scaled acording to built-in resistors */ +static const int adt7473_scaling[] = { /* .001 Volts */ + 2250, 3300 }; +#define SCALE(val, from, to) (((val) * (to) + ((from) / 2)) / (from)) static int decode_volt(int volt_index, u8 raw) { - int cmax = volt_convert_table[volt_index][0]; - int cmin = volt_convert_table[volt_index][1]; - return ((raw * (cmax - cmin)) / 255) + cmin; + return SCALE(raw, 192, adt7473_scaling[volt_index]); } static u8 encode_volt(int volt_index, int cooked) { - int cmax = volt_convert_table[volt_index][0]; - int cmin = volt_convert_table[volt_index][1]; - u8 x; - - if (cooked > cmax) - cooked = cmax; - else if (cooked < cmin) - cooked = cmin; - - x = ((cooked - cmin) * 255) / (cmax - cmin); - - return x; + int raw = SCALE(cooked, adt7473_scaling[volt_index], 192); + return SENSORS_LIMIT(raw, 0, 255); } static ssize_t show_volt_min(struct device *dev, -- Jean Delvare
