| Message ID | 20181212005503.28054-6-jeremyfertic@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | staging: iio: adt7316: dac fixes | expand |
On Tue, 11 Dec 2018 17:54:57 -0700 Jeremy Fertic <jeremyfertic@gmail.com> wrote: > The calculation of the current dac value is using the wrong bits of the > dac lsb register. Create two macros to shift the lsb register value into > lsb position, depending on whether the dac is 10 or 12 bit. Initialize > data to 0 so, with an 8 bit dac, the msb register value can be bitwise > ORed with data. > > Signed-off-by: Jeremy Fertic <jeremyfertic@gmail.com> This looks good, but with the previous 2 patches under discussion I'll hold this one for v2. Thanks Jonathan > --- > drivers/staging/iio/addac/adt7316.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/drivers/staging/iio/addac/adt7316.c b/drivers/staging/iio/addac/adt7316.c > index eee7c04f93f4..b7d12d003ddc 100644 > --- a/drivers/staging/iio/addac/adt7316.c > +++ b/drivers/staging/iio/addac/adt7316.c > @@ -47,6 +47,8 @@ > #define ADT7516_MSB_AIN3 0xA > #define ADT7516_MSB_AIN4 0xB > #define ADT7316_DA_DATA_BASE 0x10 > +#define ADT7316_DA_10_BIT_LSB_SHIFT 6 > +#define ADT7316_DA_12_BIT_LSB_SHIFT 4 > #define ADT7316_DA_MSB_DATA_REGS 4 > #define ADT7316_LSB_DAC_A 0x10 > #define ADT7316_MSB_DAC_A 0x11 > @@ -1403,7 +1405,7 @@ static IIO_DEVICE_ATTR(ex_analog_temp_offset, 0644, > static ssize_t adt7316_show_DAC(struct adt7316_chip_info *chip, > int channel, char *buf) > { > - u16 data; > + u16 data = 0; > u8 msb, lsb, offset; > int ret; > > @@ -1428,7 +1430,11 @@ static ssize_t adt7316_show_DAC(struct adt7316_chip_info *chip, > if (ret) > return -EIO; > > - data = (msb << offset) + (lsb & ((1 << offset) - 1)); > + if (chip->dac_bits == 12) > + data = lsb >> ADT7316_DA_12_BIT_LSB_SHIFT; > + else if (chip->dac_bits == 10) > + data = lsb >> ADT7316_DA_10_BIT_LSB_SHIFT; > + data |= msb << offset; > > return sprintf(buf, "%d\n", data); > }
diff --git a/drivers/staging/iio/addac/adt7316.c b/drivers/staging/iio/addac/adt7316.c index eee7c04f93f4..b7d12d003ddc 100644 --- a/drivers/staging/iio/addac/adt7316.c +++ b/drivers/staging/iio/addac/adt7316.c @@ -47,6 +47,8 @@ #define ADT7516_MSB_AIN3 0xA #define ADT7516_MSB_AIN4 0xB #define ADT7316_DA_DATA_BASE 0x10 +#define ADT7316_DA_10_BIT_LSB_SHIFT 6 +#define ADT7316_DA_12_BIT_LSB_SHIFT 4 #define ADT7316_DA_MSB_DATA_REGS 4 #define ADT7316_LSB_DAC_A 0x10 #define ADT7316_MSB_DAC_A 0x11 @@ -1403,7 +1405,7 @@ static IIO_DEVICE_ATTR(ex_analog_temp_offset, 0644, static ssize_t adt7316_show_DAC(struct adt7316_chip_info *chip, int channel, char *buf) { - u16 data; + u16 data = 0; u8 msb, lsb, offset; int ret; @@ -1428,7 +1430,11 @@ static ssize_t adt7316_show_DAC(struct adt7316_chip_info *chip, if (ret) return -EIO; - data = (msb << offset) + (lsb & ((1 << offset) - 1)); + if (chip->dac_bits == 12) + data = lsb >> ADT7316_DA_12_BIT_LSB_SHIFT; + else if (chip->dac_bits == 10) + data = lsb >> ADT7316_DA_10_BIT_LSB_SHIFT; + data |= msb << offset; return sprintf(buf, "%d\n", data); }
The calculation of the current dac value is using the wrong bits of the dac lsb register. Create two macros to shift the lsb register value into lsb position, depending on whether the dac is 10 or 12 bit. Initialize data to 0 so, with an 8 bit dac, the msb register value can be bitwise ORed with data. Signed-off-by: Jeremy Fertic <jeremyfertic@gmail.com> --- drivers/staging/iio/addac/adt7316.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)