> The way the lm85 driver currently handles the additional resolution
> bits some chips have for the voltage and temperature measurements is
> quite complex. This is my attempt to make it simpler.
>
> Signed-off-by: Jean Delvare <khali at linux-fr.org>
> ---
> drivers/hwmon/lm85.c | 32 ++++++++++++--------------------
> 1 file changed, 12 insertions(+), 20 deletions(-)
>
> --- linux-2.6.22-rc6.orig/drivers/hwmon/lm85.c 2007-07-01 14:12:18.000000000 +0200
> +++ linux-2.6.22-rc6/drivers/hwmon/lm85.c 2007-07-01 17:26:43.000000000 +0200
> @@ -139,10 +139,10 @@ static int lm85_scaling[] = { /* .001 V
> #define INS_TO_REG(n,val) \
> SENSORS_LIMIT(SCALE(val,lm85_scaling[n],192),0,255)
>
> -#define INSEXT_FROM_REG(n,val,ext,scale) \
> - SCALE((val)*(scale) + (ext),192*(scale),lm85_scaling[n])
> +#define INSEXT_FROM_REG(n,val,ext) \
> + SCALE(((val) << 4) + (ext), 192 << 4, lm85_scaling[n])
>
> -#define INS_FROM_REG(n,val) INSEXT_FROM_REG(n,val,0,1)
> +#define INS_FROM_REG(n,val) SCALE((val), 192, lm85_scaling[n])
>
> /* FAN speed is measured using 90kHz clock */
> #define FAN_TO_REG(val) (SENSORS_LIMIT( (val)<=0?0: 5400000/(val),0,65534))
> @@ -151,10 +151,9 @@ static int lm85_scaling[] = { /* .001 V
> /* Temperature is reported in .001 degC increments */
> #define TEMP_TO_REG(val) \
> SENSORS_LIMIT(SCALE(val,1000,1),-127,127)
> -#define TEMPEXT_FROM_REG(val,ext,scale) \
> - SCALE((val)*scale + (ext),scale,1000)
> -#define TEMP_FROM_REG(val) \
> - TEMPEXT_FROM_REG(val,0,1)
> +#define TEMPEXT_FROM_REG(val,ext) \
> + SCALE(((val) << 4) + (ext), 16, 1000)
> +#define TEMP_FROM_REG(val) ((val) * 1000)
>
> #define PWM_TO_REG(val) (SENSORS_LIMIT(val,0,255))
> #define PWM_FROM_REG(val) (val)
> @@ -334,7 +333,6 @@ struct lm85_data {
> u8 tach_mode; /* Register encoding, combined */
> u8 temp_ext[3]; /* Decoded values */
> u8 in_ext[8]; /* Decoded values */
> - u8 adc_scale; /* ADC Extended bits scaling factor */
> u8 fan_ppr; /* Register value */
> u8 smooth[3]; /* Register encoding */
> u8 vid; /* Register value */
> @@ -541,8 +539,7 @@ static ssize_t show_in(struct device *de
> struct lm85_data *data = lm85_update_device(dev);
> return sprintf( buf, "%d\n", INSEXT_FROM_REG(nr,
> data->in[nr],
> - data->in_ext[nr],
> - data->adc_scale) );
> + data->in_ext[nr]));
> }
>
> static ssize_t show_in_min(struct device *dev, struct device_attribute *attr,
> @@ -616,8 +613,7 @@ static ssize_t show_temp(struct device *
> int nr = to_sensor_dev_attr(attr)->index;
> struct lm85_data *data = lm85_update_device(dev);
> return sprintf(buf,"%d\n", TEMPEXT_FROM_REG(data->temp[nr],
> - data->temp_ext[nr],
> - data->adc_scale) );
> + data->temp_ext[nr]));
> }
>
> static ssize_t show_temp_min(struct device *dev, struct device_attribute *attr,
> @@ -1394,6 +1390,8 @@ static struct lm85_data *lm85_update_dev
>
> /* Have to read extended bits first to "freeze" the
> * more significant bits that are read later.
> + * There are 2 additional resolution bits per channel and we
> + * have room for 4, so we shift them to the left.
> */
> if ( (data->type == adm1027) || (data->type == adt7463) ) {
> int ext1 = lm85_read_value(client,
> @@ -1403,18 +1401,12 @@ static struct lm85_data *lm85_update_dev
> int val = (ext1 << 8) + ext2;
>
> for(i = 0; i <= 4; i++)
> - data->in_ext[i] = (val>>(i * 2))&0x03;
> + data->in_ext[i] = ((val>>(i * 2))&0x03) << 2;
>
> for(i = 0; i <= 2; i++)
> - data->temp_ext[i] = (val>>((i + 5) * 2))&0x03;
> + data->temp_ext[i] = (val>>((i + 4) * 2))&0x0c;
> }
>
> - /* adc_scale is 2^(number of LSBs). There are 4 extra bits in
> - the emc6d102 and 2 in the adt7463 and adm1027. In all
> - other chips ext is always 0 and the value of scale is
> - irrelevant. So it is left in 4*/
> - data->adc_scale = (data->type == emc6d102 ) ? 16 : 4;
> -
> data->vid = lm85_read_value(client, LM85_REG_VID);
>
> for (i = 0; i <= 3; ++i) {
>
Looks good.
Acked-by: Juerg Haefliger <juergh at gmail.com>
