Acked-by: Sonic Zhang <sonic.zhang@xxxxxxxxxx> >-----Original Message----- >From: Sascha Hauer [mailto:s.hauer@xxxxxxxxxxxxxx] >Sent: Tuesday, July 03, 2012 5:21 PM >To: linux-iio@xxxxxxxxxxxxxxx >Cc: Jonathan Cameron; Zhang, Sonic; Sascha Hauer >Subject: [PATCH 2/3] staging iio adt7410: fix 13bit mode > >The driver assumes that in 13bit mode the 16bit value has >to be shifted to the right by 3 bits. This is not true, in >both 16bit and 13bit mode the MSB is at the same position. >Currently the driver returns a temperature of 194 degrees >Celsius in 13bit mode and 24 degrees Celsius in 16bit mode. >Fix this by using the same algorithm for 16bit and 13bit >mode and by just masking out the lower three bits in 13bit >mode. > >Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> >--- > drivers/staging/iio/adc/adt7410.c | 29 ++++++++++------------------- > 1 file changed, 10 insertions(+), 19 deletions(-) > >diff --git a/drivers/staging/iio/adc/adt7410.c b/drivers/staging/iio/adc/adt7410.c >index fa54a40..f9188e5 100644 >--- a/drivers/staging/iio/adc/adt7410.c >+++ b/drivers/staging/iio/adc/adt7410.c >@@ -293,26 +293,17 @@ static ssize_t adt7410_convert_temperature(struct >adt7410_chip_info *chip, > { > char sign = ' '; > >- if (chip->config & ADT7410_RESOLUTION) { >- if (data & ADT7410_T16_VALUE_SIGN) { >- /* convert supplement to positive value */ >- data = (u16)((ADT7410_T16_VALUE_SIGN << 1) - >(u32)data); >- sign = '-'; >- } >- return sprintf(buf, "%c%d.%.7d\n", sign, >- (data >> ADT7410_T16_VALUE_FLOAT_OFFSET), >- (data & ADT7410_T16_VALUE_FLOAT_MASK) * >78125); >- } else { >- if (data & ADT7410_T13_VALUE_SIGN) { >- /* convert supplement to positive value */ >- data >>= ADT7410_T13_VALUE_OFFSET; >- data = (ADT7410_T13_VALUE_SIGN << 1) - data; >- sign = '-'; >- } >- return sprintf(buf, "%c%d.%.4d\n", sign, >- (data >> ADT7410_T13_VALUE_FLOAT_OFFSET), >- (data & ADT7410_T13_VALUE_FLOAT_MASK) * >625); >+ if (!(chip->config & ADT7410_RESOLUTION)) >+ data &= ~0x7; >+ >+ if (data & ADT7410_T16_VALUE_SIGN) { >+ /* convert supplement to positive value */ >+ data = (u16)((ADT7410_T16_VALUE_SIGN << 1) - (u32)data); >+ sign = '-'; > } >+ return sprintf(buf, "%c%d.%.7d\n", sign, >+ (data >> ADT7410_T16_VALUE_FLOAT_OFFSET), >+ (data & ADT7410_T16_VALUE_FLOAT_MASK) * 78125); > } > > static ssize_t adt7410_show_value(struct device *dev, >-- >1.7.10 > -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
