| Message ID | 20191120144756.28424-4-andrea.merello@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: max31856: provide more configuration options | expand |
On Wed, 20 Nov 2019 15:47:50 +0100 Andrea Merello <andrea.merello@gmail.com> wrote: > This sensor can perform samples averaging in hardware, but currently the > driver leaves this setting alone (default is no averaging). > > This patch binds this HW setting to the "oversampling_ratio" IIO attribute > and allows the user to set the averaging as desired (the HW supports > averaging of 2, 5, 8 or 16 samples; in-between values are rounded up). > > Cc: Hartmut Knaack <knaack.h@gmx.de> > Cc: Lars-Peter Clausen <lars@metafoo.de> > Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net> > Cc: Colin Ian King <colin.king@canonical.com> > Cc: Patrick Havelange <patrick.havelange@essensium.com> > Cc: Matt Weber <matthew.weber@rockwellcollins.com> > Cc: Matt Ranostay <matt.ranostay@konsulko.com> > Cc: Chuhong Yuan <hslester96@gmail.com> > Cc: Daniel Gomez <dagmcr@gmail.com> > Cc: linux-iio@vger.kernel.org > Signed-off-by: Andrea Merello <andrea.merello@gmail.com> Applied. Thanks, Jonathan > --- > drivers/iio/temperature/max31856.c | 43 ++++++++++++++++++++++++++++++ > 1 file changed, 43 insertions(+) > > diff --git a/drivers/iio/temperature/max31856.c b/drivers/iio/temperature/max31856.c > index d97ba9ee1598..8457ca9ae326 100644 > --- a/drivers/iio/temperature/max31856.c > +++ b/drivers/iio/temperature/max31856.c > @@ -12,6 +12,7 @@ > #include <linux/spi/spi.h> > #include <linux/iio/iio.h> > #include <linux/iio/sysfs.h> > +#include <linux/util_macros.h> > #include <dt-bindings/iio/temperature/thermocouple.h> > /* > * The MSB of the register value determines whether the following byte will > @@ -24,6 +25,8 @@ > #define MAX31856_CR0_OCFAULT BIT(4) > #define MAX31856_CR0_OCFAULT_MASK GENMASK(5, 4) > #define MAX31856_CR0_FILTER_50HZ BIT(0) > +#define MAX31856_AVERAGING_MASK GENMASK(6, 4) > +#define MAX31856_AVERAGING_SHIFT 4 > #define MAX31856_TC_TYPE_MASK GENMASK(3, 0) > #define MAX31856_FAULT_OVUV BIT(1) > #define MAX31856_FAULT_OPEN BIT(0) > @@ -51,6 +54,8 @@ static const struct iio_chan_spec max31856_channels[] = { > .type = IIO_TEMP, > .info_mask_separate = > BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), > + .info_mask_shared_by_type = > + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) > }, > { /* Cold Junction Temperature */ > .type = IIO_TEMP, > @@ -58,6 +63,8 @@ static const struct iio_chan_spec max31856_channels[] = { > .modified = 1, > .info_mask_separate = > BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), > + .info_mask_shared_by_type = > + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) > }, > }; > > @@ -65,6 +72,7 @@ struct max31856_data { > struct spi_device *spi; > u32 thermocouple_type; > bool filter_50hz; > + int averaging; > }; > > static int max31856_read(struct max31856_data *data, u8 reg, > @@ -109,6 +117,10 @@ static int max31856_init(struct max31856_data *data) > > reg_cr1_val &= ~MAX31856_TC_TYPE_MASK; > reg_cr1_val |= data->thermocouple_type; > + > + reg_cr1_val &= ~MAX31856_AVERAGING_MASK; > + reg_cr1_val |= data->averaging << MAX31856_AVERAGING_SHIFT; > + > ret = max31856_write(data, MAX31856_CR1_REG, reg_cr1_val); > if (ret) > return ret; > @@ -217,6 +229,9 @@ static int max31856_read_raw(struct iio_dev *indio_dev, > return IIO_VAL_INT_PLUS_MICRO; > } > break; > + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: > + *val = 1 << data->averaging; > + return IIO_VAL_INT; > default: > ret = -EINVAL; > break; > @@ -225,6 +240,33 @@ static int max31856_read_raw(struct iio_dev *indio_dev, > return ret; > } > > +static int max31856_write_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int val, int val2, long mask) > +{ > + struct max31856_data *data = iio_priv(indio_dev); > + int msb; > + > + switch (mask) { > + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: > + if (val > 16 || val < 1) > + return -EINVAL; > + msb = fls(val) - 1; > + /* Round up to next 2pow if needed */ > + if (BIT(msb) < val) > + msb++; > + > + data->averaging = msb; > + max31856_init(data); > + break; > + > + default: > + return -EINVAL; > + } > + > + return 0; > +} > + > static ssize_t show_fault(struct device *dev, u8 faultbit, char *buf) > { > struct iio_dev *indio_dev = dev_to_iio_dev(dev); > @@ -313,6 +355,7 @@ static const struct attribute_group max31856_group = { > > static const struct iio_info max31856_info = { > .read_raw = max31856_read_raw, > + .write_raw = max31856_write_raw, > .attrs = &max31856_group, > }; >
diff --git a/drivers/iio/temperature/max31856.c b/drivers/iio/temperature/max31856.c index d97ba9ee1598..8457ca9ae326 100644 --- a/drivers/iio/temperature/max31856.c +++ b/drivers/iio/temperature/max31856.c @@ -12,6 +12,7 @@ #include <linux/spi/spi.h> #include <linux/iio/iio.h> #include <linux/iio/sysfs.h> +#include <linux/util_macros.h> #include <dt-bindings/iio/temperature/thermocouple.h> /* * The MSB of the register value determines whether the following byte will @@ -24,6 +25,8 @@ #define MAX31856_CR0_OCFAULT BIT(4) #define MAX31856_CR0_OCFAULT_MASK GENMASK(5, 4) #define MAX31856_CR0_FILTER_50HZ BIT(0) +#define MAX31856_AVERAGING_MASK GENMASK(6, 4) +#define MAX31856_AVERAGING_SHIFT 4 #define MAX31856_TC_TYPE_MASK GENMASK(3, 0) #define MAX31856_FAULT_OVUV BIT(1) #define MAX31856_FAULT_OPEN BIT(0) @@ -51,6 +54,8 @@ static const struct iio_chan_spec max31856_channels[] = { .type = IIO_TEMP, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), + .info_mask_shared_by_type = + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) }, { /* Cold Junction Temperature */ .type = IIO_TEMP, @@ -58,6 +63,8 @@ static const struct iio_chan_spec max31856_channels[] = { .modified = 1, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), + .info_mask_shared_by_type = + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) }, }; @@ -65,6 +72,7 @@ struct max31856_data { struct spi_device *spi; u32 thermocouple_type; bool filter_50hz; + int averaging; }; static int max31856_read(struct max31856_data *data, u8 reg, @@ -109,6 +117,10 @@ static int max31856_init(struct max31856_data *data) reg_cr1_val &= ~MAX31856_TC_TYPE_MASK; reg_cr1_val |= data->thermocouple_type; + + reg_cr1_val &= ~MAX31856_AVERAGING_MASK; + reg_cr1_val |= data->averaging << MAX31856_AVERAGING_SHIFT; + ret = max31856_write(data, MAX31856_CR1_REG, reg_cr1_val); if (ret) return ret; @@ -217,6 +229,9 @@ static int max31856_read_raw(struct iio_dev *indio_dev, return IIO_VAL_INT_PLUS_MICRO; } break; + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + *val = 1 << data->averaging; + return IIO_VAL_INT; default: ret = -EINVAL; break; @@ -225,6 +240,33 @@ static int max31856_read_raw(struct iio_dev *indio_dev, return ret; } +static int max31856_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct max31856_data *data = iio_priv(indio_dev); + int msb; + + switch (mask) { + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + if (val > 16 || val < 1) + return -EINVAL; + msb = fls(val) - 1; + /* Round up to next 2pow if needed */ + if (BIT(msb) < val) + msb++; + + data->averaging = msb; + max31856_init(data); + break; + + default: + return -EINVAL; + } + + return 0; +} + static ssize_t show_fault(struct device *dev, u8 faultbit, char *buf) { struct iio_dev *indio_dev = dev_to_iio_dev(dev); @@ -313,6 +355,7 @@ static const struct attribute_group max31856_group = { static const struct iio_info max31856_info = { .read_raw = max31856_read_raw, + .write_raw = max31856_write_raw, .attrs = &max31856_group, };
This sensor can perform samples averaging in hardware, but currently the driver leaves this setting alone (default is no averaging). This patch binds this HW setting to the "oversampling_ratio" IIO attribute and allows the user to set the averaging as desired (the HW supports averaging of 2, 5, 8 or 16 samples; in-between values are rounded up). Cc: Hartmut Knaack <knaack.h@gmx.de> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net> Cc: Colin Ian King <colin.king@canonical.com> Cc: Patrick Havelange <patrick.havelange@essensium.com> Cc: Matt Weber <matthew.weber@rockwellcollins.com> Cc: Matt Ranostay <matt.ranostay@konsulko.com> Cc: Chuhong Yuan <hslester96@gmail.com> Cc: Daniel Gomez <dagmcr@gmail.com> Cc: linux-iio@vger.kernel.org Signed-off-by: Andrea Merello <andrea.merello@gmail.com> --- drivers/iio/temperature/max31856.c | 43 ++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+)