Re: [PATCH v2 2/3] iio: adc: Fix integration time/averaging for INA219/220

From: Jonathan Cameron
Date: Sat Jun 03 2017 - 05:03:39 EST


On Sun, 28 May 2017 17:00:51 +0100
Jonathan Cameron <jic23@xxxxxxxxxx> wrote:

> On Wed, 24 May 2017 20:50:45 +0100
> Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
>
> > On Wed, 24 May 2017 02:09:06 +0200
> > Stefan BrÃns <stefan.bruens@xxxxxxxxxxxxxx> wrote:
> >
> > > INA226/230/231 has integration times per voltage channel and common
> > > averaging setting for both channels, while the INA219/220 only has a
> > > combined integration time/averaging setting per channel.
> > > Only expose the averaging attribute for the INA226, and expose the correct
> > > integration times for the INA219.
> > >
> > > Signed-off-by: Stefan BrÃns <stefan.bruens@xxxxxxxxxxxxxx>
> > One comment inline, but not really anything I want you to change.
> >
> > I would like some input from Marc or perhaps Andrew on this though.
>
> I'll give this another week I think and if we don't here anything
> go with it as is. Give me a poke if I look to have missed it though!
Long enough. I guess everyone is busy.

Applied to the togreg branch of iio.git and pushed out as testing for
the autobuilders to play with it.

Thanks,

Jonathan
>
> Jonathan
> > > ---
> > > drivers/iio/adc/ina2xx-adc.c | 204 ++++++++++++++++++++++++++++++++++++++-----
> > > 1 file changed, 182 insertions(+), 22 deletions(-)
> > >
> > > diff --git a/drivers/iio/adc/ina2xx-adc.c b/drivers/iio/adc/ina2xx-adc.c
> > > index bba10a1b2fcb..232c0b80d658 100644
> > > --- a/drivers/iio/adc/ina2xx-adc.c
> > > +++ b/drivers/iio/adc/ina2xx-adc.c
> > > @@ -49,6 +49,7 @@
> > >
> > > /* settings - depend on use case */
> > > #define INA219_CONFIG_DEFAULT 0x399F /* PGA=8 */
> > > +#define INA219_DEFAULT_IT 532
> > > #define INA226_CONFIG_DEFAULT 0x4327
> > > #define INA226_DEFAULT_AVG 4
> > > #define INA226_DEFAULT_IT 1110
> > > @@ -56,19 +57,24 @@
> > > #define INA2XX_RSHUNT_DEFAULT 10000
> > >
> > > /*
> > > - * bit mask for reading the averaging setting in the configuration register
> > > + * bit masks for reading the settings in the configuration register
> > > * FIXME: use regmap_fields.
> > > */
> > > #define INA2XX_MODE_MASK GENMASK(3, 0)
> > >
> > > +/* Averaging for VBus/VShunt/Power */
> > > #define INA226_AVG_MASK GENMASK(11, 9)
> > > #define INA226_SHIFT_AVG(val) ((val) << 9)
> > >
> > > /* Integration time for VBus */
> > > +#define INA219_ITB_MASK GENMASK(10, 7)
> > > +#define INA219_SHIFT_ITB(val) ((val) << 7)
> > > #define INA226_ITB_MASK GENMASK(8, 6)
> > > #define INA226_SHIFT_ITB(val) ((val) << 6)
> > >
> > > /* Integration time for VShunt */
> > > +#define INA219_ITS_MASK GENMASK(6, 3)
> > > +#define INA219_SHIFT_ITS(val) ((val) << 3)
> > > #define INA226_ITS_MASK GENMASK(5, 3)
> > > #define INA226_SHIFT_ITS(val) ((val) << 3)
> > >
> > > @@ -108,6 +114,7 @@ struct ina2xx_config {
> > > int bus_voltage_shift;
> > > int bus_voltage_lsb; /* uV */
> > > int power_lsb; /* uW */
> > > + enum ina2xx_ids chip_id;
> > I wonder if it would be cleaner to have someting more
> > specific than simply an ID? Chances are as more parts
> > get added we'll get a steadily growing list of quirks
> > on different sets of them.
> >
> > Mind you can always make that sort of generalization if /
> > when it is needed ;)
> > > };
> > >
> > > struct ina2xx_chip_info {
> > > @@ -130,6 +137,7 @@ static const struct ina2xx_config ina2xx_config[] = {
> > > .bus_voltage_shift = 3,
> > > .bus_voltage_lsb = 4000,
> > > .power_lsb = 20000,
> > > + .chip_id = ina219,
> > > },
> > > [ina226] = {
> > > .config_default = INA226_CONFIG_DEFAULT,
> > > @@ -138,6 +146,7 @@ static const struct ina2xx_config ina2xx_config[] = {
> > > .bus_voltage_shift = 0,
> > > .bus_voltage_lsb = 1250,
> > > .power_lsb = 25000,
> > > + .chip_id = ina226,
> > > },
> > > };
> > >
> > > @@ -283,6 +292,66 @@ static int ina226_set_int_time_vshunt(struct ina2xx_chip_info *chip,
> > > return 0;
> > > }
> > >
> > > +/* Conversion times in uS. */
> > > +static const int ina219_conv_time_tab_subsample[] = { 84, 148, 276, 532 };
> > > +static const int ina219_conv_time_tab_average[] = { 532, 1060, 2130, 4260,
> > > + 8510, 17020, 34050, 68100};
> > > +
> > > +static int ina219_lookup_int_time(unsigned int *val_us, int *bits)
> > > +{
> > > + if (*val_us > 68100 || *val_us < 84)
> > > + return -EINVAL;
> > > +
> > > + if (*val_us <= 532) {
> > > + *bits = find_closest(*val_us, ina219_conv_time_tab_subsample,
> > > + ARRAY_SIZE(ina219_conv_time_tab_subsample));
> > > + *val_us = ina219_conv_time_tab_subsample[*bits];
> > > + } else {
> > > + *bits = find_closest(*val_us, ina219_conv_time_tab_average,
> > > + ARRAY_SIZE(ina219_conv_time_tab_average));
> > > + *val_us = ina219_conv_time_tab_average[*bits];
> > > + *bits |= 0x8;
> > > + }
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static int ina219_set_int_time_vbus(struct ina2xx_chip_info *chip,
> > > + unsigned int val_us, unsigned int *config)
> > > +{
> > > + int bits, ret;
> > > + unsigned int val_us_best = val_us;
> > > +
> > > + ret = ina219_lookup_int_time(&val_us_best, &bits);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + chip->int_time_vbus = val_us_best;
> > > +
> > > + *config &= ~INA219_ITB_MASK;
> > > + *config |= INA219_SHIFT_ITB(bits) & INA219_ITB_MASK;
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static int ina219_set_int_time_vshunt(struct ina2xx_chip_info *chip,
> > > + unsigned int val_us, unsigned int *config)
> > > +{
> > > + int bits, ret;
> > > + unsigned int val_us_best = val_us;
> > > +
> > > + ret = ina219_lookup_int_time(&val_us_best, &bits);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + chip->int_time_vshunt = val_us_best;
> > > +
> > > + *config &= ~INA219_ITS_MASK;
> > > + *config |= INA219_SHIFT_ITS(bits) & INA219_ITS_MASK;
> > > +
> > > + return 0;
> > > +}
> > > +
> > > static int ina2xx_write_raw(struct iio_dev *indio_dev,
> > > struct iio_chan_spec const *chan,
> > > int val, int val2, long mask)
> > > @@ -308,10 +377,21 @@ static int ina2xx_write_raw(struct iio_dev *indio_dev,
> > > break;
> > >
> > > case IIO_CHAN_INFO_INT_TIME:
> > > - if (chan->address == INA2XX_SHUNT_VOLTAGE)
> > > - ret = ina226_set_int_time_vshunt(chip, val2, &tmp);
> > > - else
> > > - ret = ina226_set_int_time_vbus(chip, val2, &tmp);
> > > + if (chip->config->chip_id == ina226) {
> > > + if (chan->address == INA2XX_SHUNT_VOLTAGE)
> > > + ret = ina226_set_int_time_vshunt(chip, val2,
> > > + &tmp);
> > > + else
> > > + ret = ina226_set_int_time_vbus(chip, val2,
> > > + &tmp);
> > > + } else {
> > > + if (chan->address == INA2XX_SHUNT_VOLTAGE)
> > > + ret = ina219_set_int_time_vshunt(chip, val2,
> > > + &tmp);
> > > + else
> > > + ret = ina219_set_int_time_vbus(chip, val2,
> > > + &tmp);
> > > + }
> > > break;
> > >
> > > default:
> > > @@ -412,7 +492,24 @@ static ssize_t ina2xx_shunt_resistor_store(struct device *dev,
> > > return len;
> > > }
> > >
> > > -#define INA2XX_CHAN(_type, _index, _address) { \
> > > +#define INA219_CHAN(_type, _index, _address) { \
> > > + .type = (_type), \
> > > + .address = (_address), \
> > > + .indexed = 1, \
> > > + .channel = (_index), \
> > > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
> > > + BIT(IIO_CHAN_INFO_SCALE), \
> > > + .info_mask_shared_by_dir = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> > > + .scan_index = (_index), \
> > > + .scan_type = { \
> > > + .sign = 'u', \
> > > + .realbits = 16, \
> > > + .storagebits = 16, \
> > > + .endianness = IIO_CPU, \
> > > + } \
> > > +}
> > > +
> > > +#define INA226_CHAN(_type, _index, _address) { \
> > > .type = (_type), \
> > > .address = (_address), \
> > > .indexed = 1, \
> > > @@ -434,7 +531,25 @@ static ssize_t ina2xx_shunt_resistor_store(struct device *dev,
> > > * Sampling Freq is a consequence of the integration times of
> > > * the Voltage channels.
> > > */
> > > -#define INA2XX_CHAN_VOLTAGE(_index, _address) { \
> > > +#define INA219_CHAN_VOLTAGE(_index, _address) { \
> > > + .type = IIO_VOLTAGE, \
> > > + .address = (_address), \
> > > + .indexed = 1, \
> > > + .channel = (_index), \
> > > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
> > > + BIT(IIO_CHAN_INFO_SCALE) | \
> > > + BIT(IIO_CHAN_INFO_INT_TIME), \
> > > + .info_mask_shared_by_dir = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> > > + .scan_index = (_index), \
> > > + .scan_type = { \
> > > + .sign = 'u', \
> > > + .realbits = 16, \
> > > + .storagebits = 16, \
> > > + .endianness = IIO_LE, \
> > > + } \
> > > +}
> > > +
> > > +#define INA226_CHAN_VOLTAGE(_index, _address) { \
> > > .type = IIO_VOLTAGE, \
> > > .address = (_address), \
> > > .indexed = 1, \
> > > @@ -453,11 +568,20 @@ static ssize_t ina2xx_shunt_resistor_store(struct device *dev,
> > > } \
> > > }
> > >
> > > -static const struct iio_chan_spec ina2xx_channels[] = {
> > > - INA2XX_CHAN_VOLTAGE(0, INA2XX_SHUNT_VOLTAGE),
> > > - INA2XX_CHAN_VOLTAGE(1, INA2XX_BUS_VOLTAGE),
> > > - INA2XX_CHAN(IIO_POWER, 2, INA2XX_POWER),
> > > - INA2XX_CHAN(IIO_CURRENT, 3, INA2XX_CURRENT),
> > > +
> > > +static const struct iio_chan_spec ina226_channels[] = {
> > > + INA226_CHAN_VOLTAGE(0, INA2XX_SHUNT_VOLTAGE),
> > > + INA226_CHAN_VOLTAGE(1, INA2XX_BUS_VOLTAGE),
> > > + INA226_CHAN(IIO_POWER, 2, INA2XX_POWER),
> > > + INA226_CHAN(IIO_CURRENT, 3, INA2XX_CURRENT),
> > > + IIO_CHAN_SOFT_TIMESTAMP(4),
> > > +};
> > > +
> > > +static const struct iio_chan_spec ina219_channels[] = {
> > > + INA219_CHAN_VOLTAGE(0, INA2XX_SHUNT_VOLTAGE),
> > > + INA219_CHAN_VOLTAGE(1, INA2XX_BUS_VOLTAGE),
> > > + INA219_CHAN(IIO_POWER, 2, INA2XX_POWER),
> > > + INA219_CHAN(IIO_CURRENT, 3, INA2XX_CURRENT),
> > > IIO_CHAN_SOFT_TIMESTAMP(4),
> > > };
> > >
> > > @@ -592,7 +716,14 @@ static int ina2xx_debug_reg(struct iio_dev *indio_dev,
> > > }
> > >
> > > /* Possible integration times for vshunt and vbus */
> > > -static IIO_CONST_ATTR_INT_TIME_AVAIL("0.000140 0.000204 0.000332 0.000588 0.001100 0.002116 0.004156 0.008244");
> > > +static IIO_CONST_ATTR_NAMED(ina219_integration_time_available,
> > > + integration_time_available,
> > > + "0.000084 0.000148 0.000276 0.000532 0.001060 0.002130 0.004260 0.008510 0.017020 0.034050 0.068100");
> > > +
> > > +static IIO_CONST_ATTR_NAMED(ina226_integration_time_available,
> > > + integration_time_available,
> > > + "0.000140 0.000204 0.000332 0.000588 0.001100 0.002116 0.004156 0.008244");
> > > +
> > >
> > > static IIO_DEVICE_ATTR(in_allow_async_readout, S_IRUGO | S_IWUSR,
> > > ina2xx_allow_async_readout_show,
> > > @@ -602,20 +733,39 @@ static IIO_DEVICE_ATTR(in_shunt_resistor, S_IRUGO | S_IWUSR,
> > > ina2xx_shunt_resistor_show,
> > > ina2xx_shunt_resistor_store, 0);
> > >
> > > -static struct attribute *ina2xx_attributes[] = {
> > > +static struct attribute *ina219_attributes[] = {
> > > + &iio_dev_attr_in_allow_async_readout.dev_attr.attr,
> > > + &iio_const_attr_ina219_integration_time_available.dev_attr.attr,
> > > + &iio_dev_attr_in_shunt_resistor.dev_attr.attr,
> > > + NULL,
> > > +};
> > > +
> > > +static struct attribute *ina226_attributes[] = {
> > > &iio_dev_attr_in_allow_async_readout.dev_attr.attr,
> > > - &iio_const_attr_integration_time_available.dev_attr.attr,
> > > + &iio_const_attr_ina226_integration_time_available.dev_attr.attr,
> > > &iio_dev_attr_in_shunt_resistor.dev_attr.attr,
> > > NULL,
> > > };
> > >
> > > -static const struct attribute_group ina2xx_attribute_group = {
> > > - .attrs = ina2xx_attributes,
> > > +static const struct attribute_group ina219_attribute_group = {
> > > + .attrs = ina219_attributes,
> > > };
> > >
> > > -static const struct iio_info ina2xx_info = {
> > > +static const struct attribute_group ina226_attribute_group = {
> > > + .attrs = ina226_attributes,
> > > +};
> > > +
> > > +static const struct iio_info ina219_info = {
> > > + .driver_module = THIS_MODULE,
> > > + .attrs = &ina219_attribute_group,
> > > + .read_raw = ina2xx_read_raw,
> > > + .write_raw = ina2xx_write_raw,
> > > + .debugfs_reg_access = ina2xx_debug_reg,
> > > +};
> > > +
> > > +static const struct iio_info ina226_info = {
> > > .driver_module = THIS_MODULE,
> > > - .attrs = &ina2xx_attribute_group,
> > > + .attrs = &ina226_attribute_group,
> > > .read_raw = ina2xx_read_raw,
> > > .write_raw = ina2xx_write_raw,
> > > .debugfs_reg_access = ina2xx_debug_reg,
> > > @@ -686,6 +836,10 @@ static int ina2xx_probe(struct i2c_client *client,
> > > ina226_set_average(chip, INA226_DEFAULT_AVG, &val);
> > > ina226_set_int_time_vbus(chip, INA226_DEFAULT_IT, &val);
> > > ina226_set_int_time_vshunt(chip, INA226_DEFAULT_IT, &val);
> > > + } else {
> > > + chip->avg = 1;
> > > + ina219_set_int_time_vbus(chip, INA219_DEFAULT_IT, &val);
> > > + ina219_set_int_time_vshunt(chip, INA219_DEFAULT_IT, &val);
> > > }
> > >
> > > ret = ina2xx_init(chip, val);
> > > @@ -697,10 +851,16 @@ static int ina2xx_probe(struct i2c_client *client,
> > > indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
> > > indio_dev->dev.parent = &client->dev;
> > > indio_dev->dev.of_node = client->dev.of_node;
> > > - indio_dev->channels = ina2xx_channels;
> > > - indio_dev->num_channels = ARRAY_SIZE(ina2xx_channels);
> > > + if (id->driver_data == ina226) {
> > > + indio_dev->channels = ina226_channels;
> > > + indio_dev->num_channels = ARRAY_SIZE(ina226_channels);
> > > + indio_dev->info = &ina226_info;
> > > + } else {
> > > + indio_dev->channels = ina219_channels;
> > > + indio_dev->num_channels = ARRAY_SIZE(ina219_channels);
> > > + indio_dev->info = &ina219_info;
> > > + }
> > > indio_dev->name = id->name;
> > > - indio_dev->info = &ina2xx_info;
> > > indio_dev->setup_ops = &ina2xx_setup_ops;
> > >
> > > buffer = devm_iio_kfifo_allocate(&indio_dev->dev);
> >
> > --
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