| Message ID | 20210713043425.3321230-4-liambeguin@gmail.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Jonathan Cameron |
| Headers | show |
| Series | AD7949 Fixes | expand |
On Tue, 13 Jul 2021 00:34:24 -0400 Liam Beguin <liambeguin@gmail.com> wrote: > From: Liam Beguin <lvb@xiphos.com> > > Add support for selecting a custom reference voltage from the > devicetree. If an external source is used, a vref regulator should be > defined in the devicetree. > > Signed-off-by: Liam Beguin <lvb@xiphos.com> Hi Liam, A few minor things inline. Jonathan > --- > drivers/iio/adc/ad7949.c | 133 +++++++++++++++++++++++++++++++++------ > 1 file changed, 115 insertions(+), 18 deletions(-) > > diff --git a/drivers/iio/adc/ad7949.c b/drivers/iio/adc/ad7949.c > index 65f78751225b..8b78da7ead36 100644 > --- a/drivers/iio/adc/ad7949.c > +++ b/drivers/iio/adc/ad7949.c > @@ -36,7 +36,11 @@ > > /* REF: reference/buffer selection */ > #define AD7949_CFG_BIT_REF GENMASK(5, 3) > -#define AD7949_CFG_VAL_REF_EXT_BUF 7 > +#define AD7949_CFG_VAL_REF_EXT_TEMP_BUF 3 > +#define AD7949_CFG_VAL_REF_EXT_TEMP 2 > +#define AD7949_CFG_VAL_REF_INT_4096 1 > +#define AD7949_CFG_VAL_REF_INT_2500 0 > +#define AD7949_CFG_VAL_REF_EXTERNAL BIT(1) > > /* SEQ: channel sequencer. Allows for scanning channels */ > #define AD7949_CFG_BIT_SEQ GENMASK(2, 1) > @@ -61,6 +65,14 @@ static const struct ad7949_adc_spec ad7949_adc_spec[] = { > [ID_AD7689] = { .num_channels = 8, .resolution = 16 }, > }; > > +/** > + * struct ad7949_channel - ADC Channel parameters > + * @refsel: reference selection > + */ > +struct ad7949_channel { > + u32 refsel; > +}; > + > /** > * struct ad7949_adc_chip - AD ADC chip > * @lock: protects write sequences > @@ -78,6 +90,7 @@ struct ad7949_adc_chip { > struct regulator *vref; > struct iio_dev *indio_dev; > struct spi_device *spi; > + struct ad7949_channel *channels; > u8 resolution; > u8 bits_per_word; > u16 cfg; > @@ -138,6 +151,7 @@ static int ad7949_spi_read_channel(struct ad7949_adc_chip *ad7949_adc, int *val, > int i; > u8 buf8[2]; > struct spi_message msg; > + struct ad7949_channel ad7949_chan = ad7949_adc->channels[channel]; Better to use a pointer rather than copying the data. > struct spi_transfer tx[] = { > { > .rx_buf = &ad7949_adc->buffer, > @@ -154,8 +168,9 @@ static int ad7949_spi_read_channel(struct ad7949_adc_chip *ad7949_adc, int *val, > */ > for (i = 0; i < 2; i++) { > ret = ad7949_spi_write_cfg(ad7949_adc, > - FIELD_PREP(AD7949_CFG_BIT_INX, channel), > - AD7949_CFG_BIT_INX); > + FIELD_PREP(AD7949_CFG_BIT_INX, channel) | > + FIELD_PREP(AD7949_CFG_BIT_REF, ad7949_chan.refsel), > + AD7949_CFG_BIT_INX | AD7949_CFG_BIT_REF); > if (ret) > return ret; > if (channel == ad7949_adc->current_channel) > @@ -225,6 +240,7 @@ static int ad7949_spi_read_raw(struct iio_dev *indio_dev, > int *val, int *val2, long mask) > { > struct ad7949_adc_chip *ad7949_adc = iio_priv(indio_dev); > + struct ad7949_channel ad7949_chan = ad7949_adc->channels[chan->channel]; > int ret; > > if (!val) > @@ -242,12 +258,26 @@ static int ad7949_spi_read_raw(struct iio_dev *indio_dev, > return IIO_VAL_INT; > > case IIO_CHAN_INFO_SCALE: > - ret = regulator_get_voltage(ad7949_adc->vref); > - if (ret < 0) > - return ret; > + switch (ad7949_chan.refsel) { > + case AD7949_CFG_VAL_REF_INT_2500: > + *val = 2500; > + break; > + case AD7949_CFG_VAL_REF_INT_4096: > + *val = 4096; > + break; > + case AD7949_CFG_VAL_REF_EXT_TEMP: > + case AD7949_CFG_VAL_REF_EXT_TEMP_BUF: > + ret = regulator_get_voltage(ad7949_adc->vref); > + if (ret < 0) > + return ret; > + > + /* convert value back to mV */ > + *val = ret / 1000; > + break; > + } > > - *val = ret / 5000; > - return IIO_VAL_INT; > + *val2 = (1 << ad7949_adc->resolution) - 1; > + return IIO_VAL_FRACTIONAL; > } > > return -EINVAL; > @@ -286,7 +316,7 @@ static int ad7949_spi_init(struct ad7949_adc_chip *ad7949_adc) > FIELD_PREP(AD7949_CFG_BIT_INCC, AD7949_CFG_VAL_INCC_UNIPOLAR_GND) | > FIELD_PREP(AD7949_CFG_BIT_INX, ad7949_adc->current_channel) | > FIELD_PREP(AD7949_CFG_BIT_BW_FULL, 1) | > - FIELD_PREP(AD7949_CFG_BIT_REF, AD7949_CFG_VAL_REF_EXT_BUF) | > + FIELD_PREP(AD7949_CFG_BIT_REF, ad7949_adc->channels[0].refsel) | > FIELD_PREP(AD7949_CFG_BIT_SEQ, 0x0) | > FIELD_PREP(AD7949_CFG_BIT_RBN, 1); > > @@ -302,14 +332,24 @@ static int ad7949_spi_init(struct ad7949_adc_chip *ad7949_adc) > return ret; > } > > +static void ad7949_disable_reg(void *reg) > +{ > + regulator_disable(reg); > +} > + > static int ad7949_spi_probe(struct spi_device *spi) > { > u32 spi_ctrl_mask = spi->controller->bits_per_word_mask; > struct device *dev = &spi->dev; > const struct ad7949_adc_spec *spec; > struct ad7949_adc_chip *ad7949_adc; > + struct ad7949_channel *ad7949_chan; > + struct device_node *child; > struct iio_dev *indio_dev; > + int mode; > + u32 tmp; > int ret; > + int i; > > indio_dev = devm_iio_device_alloc(dev, sizeof(*ad7949_adc)); > if (!indio_dev) { > @@ -343,16 +383,75 @@ static int ad7949_spi_probe(struct spi_device *spi) > return -EINVAL; > } > > - ad7949_adc->vref = devm_regulator_get(dev, "vref"); > + /* Setup external voltage ref, buffered? */ > + ad7949_adc->vref = devm_regulator_get(dev, "vrefin"); > if (IS_ERR(ad7949_adc->vref)) { > - dev_err(dev, "fail to request regulator\n"); > - return PTR_ERR(ad7949_adc->vref); > + /* unbuffered? */ > + ad7949_adc->vref = devm_regulator_get(dev, "vref"); > + if (IS_ERR(ad7949_adc->vref)) { > + /* Internal then */ > + mode = AD7949_CFG_VAL_REF_INT_4096; > + } > + mode = AD7949_CFG_VAL_REF_EXT_TEMP; > } > + mode = AD7949_CFG_VAL_REF_EXT_TEMP_BUF; > > - ret = regulator_enable(ad7949_adc->vref); > - if (ret < 0) { > - dev_err(dev, "fail to enable regulator\n"); > - return ret; > + if (mode > AD7949_CFG_VAL_REF_INT_4096) { Range checks on enum values are always rather messy. So better to explicitly match the cases that matter. > + ret = regulator_enable(ad7949_adc->vref); > + if (ret < 0) { > + dev_err(dev, "fail to enable regulator\n"); > + return ret; > + } > + > + ret = devm_add_action_or_reset(dev, ad7949_disable_reg, > + ad7949_adc->vref); > + if (ret) > + return ret; > + } > + > + ad7949_adc->channels = devm_kcalloc(dev, spec->num_channels, > + sizeof(*ad7949_adc->channels), > + GFP_KERNEL); > + if (!ad7949_adc->channels) { > + dev_err(dev, "unable to allocate ADC channels\n"); > + return -ENOMEM; > + } > + > + /* Initialize all channel structures */ > + for (i = 0; i < spec->num_channels; i++) { > + ad7949_adc->channels[i].refsel = mode; Kernel style is no brackets when only one item in a block. > + } > + > + /* Read channel specific information form the devicetree */ > + for_each_child_of_node(dev->of_node, child) { > + ret = of_property_read_u32(child, "reg", &i); > + if (ret) { > + dev_err(dev, "missing reg property in child: %s\n", > + child->full_name); > + of_node_put(child); > + return ret; > + } > + > + ad7949_chan = &ad7949_adc->channels[i]; > + > + ret = of_property_read_u32(child, "adi,internal-ref-mv", &tmp); Preference for generic device firmware properties not of_* specific ones. I think there is nothing stopping this driver being probed from ACPI via PRP0001 before this change. Note you'll also need fwnode_for_each_child_node() above. > + if (ret < 0 && ret != -EINVAL) { > + of_node_put(child); > + return ret; > + } > + > + switch (tmp) { > + case 2500: > + ad7949_chan->refsel = AD7949_CFG_VAL_REF_INT_2500; > + break; > + case 4096: > + ad7949_chan->refsel = AD7949_CFG_VAL_REF_INT_4096; > + break; > + default: > + dev_err(dev, "unsupported internal voltage reference\n"); > + of_node_put(child); > + return -EINVAL; > + } > } > > mutex_init(&ad7949_adc->lock); > @@ -373,7 +472,6 @@ static int ad7949_spi_probe(struct spi_device *spi) > > err: > mutex_destroy(&ad7949_adc->lock); > - regulator_disable(ad7949_adc->vref); > > return ret; > } > @@ -385,7 +483,6 @@ static int ad7949_spi_remove(struct spi_device *spi) > > iio_device_unregister(indio_dev); > mutex_destroy(&ad7949_adc->lock); > - regulator_disable(ad7949_adc->vref); Given mutex_destroy is mostly pointless (and definitely is here) that leaves us with just iio_device_register(). Hence if you could do a follow up patch finishing conversion of this to entirely devm managed that would be a nice addition to this series (or separate patch is fine as well). > > return 0; > }
On Sat Jul 17, 2021 at 1:34 PM EDT, Jonathan Cameron wrote: > On Tue, 13 Jul 2021 00:34:24 -0400 > Liam Beguin <liambeguin@gmail.com> wrote: > > > From: Liam Beguin <lvb@xiphos.com> > > > > Add support for selecting a custom reference voltage from the > > devicetree. If an external source is used, a vref regulator should be > > defined in the devicetree. > > > > Signed-off-by: Liam Beguin <lvb@xiphos.com> > > Hi Liam, > > A few minor things inline. > > Jonathan > > > --- > > drivers/iio/adc/ad7949.c | 133 +++++++++++++++++++++++++++++++++------ > > 1 file changed, 115 insertions(+), 18 deletions(-) > > > > diff --git a/drivers/iio/adc/ad7949.c b/drivers/iio/adc/ad7949.c > > index 65f78751225b..8b78da7ead36 100644 > > --- a/drivers/iio/adc/ad7949.c > > +++ b/drivers/iio/adc/ad7949.c > > @@ -36,7 +36,11 @@ > > > > /* REF: reference/buffer selection */ > > #define AD7949_CFG_BIT_REF GENMASK(5, 3) > > -#define AD7949_CFG_VAL_REF_EXT_BUF 7 > > +#define AD7949_CFG_VAL_REF_EXT_TEMP_BUF 3 > > +#define AD7949_CFG_VAL_REF_EXT_TEMP 2 > > +#define AD7949_CFG_VAL_REF_INT_4096 1 > > +#define AD7949_CFG_VAL_REF_INT_2500 0 > > +#define AD7949_CFG_VAL_REF_EXTERNAL BIT(1) > > > > /* SEQ: channel sequencer. Allows for scanning channels */ > > #define AD7949_CFG_BIT_SEQ GENMASK(2, 1) > > @@ -61,6 +65,14 @@ static const struct ad7949_adc_spec ad7949_adc_spec[] = { > > [ID_AD7689] = { .num_channels = 8, .resolution = 16 }, > > }; > > > > +/** > > + * struct ad7949_channel - ADC Channel parameters > > + * @refsel: reference selection > > + */ > > +struct ad7949_channel { > > + u32 refsel; > > +}; > > + > > /** > > * struct ad7949_adc_chip - AD ADC chip > > * @lock: protects write sequences > > @@ -78,6 +90,7 @@ struct ad7949_adc_chip { > > struct regulator *vref; > > struct iio_dev *indio_dev; > > struct spi_device *spi; > > + struct ad7949_channel *channels; > > u8 resolution; > > u8 bits_per_word; > > u16 cfg; > > @@ -138,6 +151,7 @@ static int ad7949_spi_read_channel(struct ad7949_adc_chip *ad7949_adc, int *val, > > int i; > > u8 buf8[2]; > > struct spi_message msg; > > + struct ad7949_channel ad7949_chan = ad7949_adc->channels[channel]; > > Better to use a pointer rather than copying the data. > > > struct spi_transfer tx[] = { > > { > > .rx_buf = &ad7949_adc->buffer, > > @@ -154,8 +168,9 @@ static int ad7949_spi_read_channel(struct ad7949_adc_chip *ad7949_adc, int *val, > > */ > > for (i = 0; i < 2; i++) { > > ret = ad7949_spi_write_cfg(ad7949_adc, > > - FIELD_PREP(AD7949_CFG_BIT_INX, channel), > > - AD7949_CFG_BIT_INX); > > + FIELD_PREP(AD7949_CFG_BIT_INX, channel) | > > + FIELD_PREP(AD7949_CFG_BIT_REF, ad7949_chan.refsel), > > + AD7949_CFG_BIT_INX | AD7949_CFG_BIT_REF); > > if (ret) > > return ret; > > if (channel == ad7949_adc->current_channel) > > @@ -225,6 +240,7 @@ static int ad7949_spi_read_raw(struct iio_dev *indio_dev, > > int *val, int *val2, long mask) > > { > > struct ad7949_adc_chip *ad7949_adc = iio_priv(indio_dev); > > + struct ad7949_channel ad7949_chan = ad7949_adc->channels[chan->channel]; > > int ret; > > > > if (!val) > > @@ -242,12 +258,26 @@ static int ad7949_spi_read_raw(struct iio_dev *indio_dev, > > return IIO_VAL_INT; > > > > case IIO_CHAN_INFO_SCALE: > > - ret = regulator_get_voltage(ad7949_adc->vref); > > - if (ret < 0) > > - return ret; > > + switch (ad7949_chan.refsel) { > > + case AD7949_CFG_VAL_REF_INT_2500: > > + *val = 2500; > > + break; > > + case AD7949_CFG_VAL_REF_INT_4096: > > + *val = 4096; > > + break; > > + case AD7949_CFG_VAL_REF_EXT_TEMP: > > + case AD7949_CFG_VAL_REF_EXT_TEMP_BUF: > > + ret = regulator_get_voltage(ad7949_adc->vref); > > + if (ret < 0) > > + return ret; > > + > > + /* convert value back to mV */ > > + *val = ret / 1000; > > + break; > > + } > > > > - *val = ret / 5000; > > - return IIO_VAL_INT; > > + *val2 = (1 << ad7949_adc->resolution) - 1; > > + return IIO_VAL_FRACTIONAL; > > } > > > > return -EINVAL; > > @@ -286,7 +316,7 @@ static int ad7949_spi_init(struct ad7949_adc_chip *ad7949_adc) > > FIELD_PREP(AD7949_CFG_BIT_INCC, AD7949_CFG_VAL_INCC_UNIPOLAR_GND) | > > FIELD_PREP(AD7949_CFG_BIT_INX, ad7949_adc->current_channel) | > > FIELD_PREP(AD7949_CFG_BIT_BW_FULL, 1) | > > - FIELD_PREP(AD7949_CFG_BIT_REF, AD7949_CFG_VAL_REF_EXT_BUF) | > > + FIELD_PREP(AD7949_CFG_BIT_REF, ad7949_adc->channels[0].refsel) | > > FIELD_PREP(AD7949_CFG_BIT_SEQ, 0x0) | > > FIELD_PREP(AD7949_CFG_BIT_RBN, 1); > > > > @@ -302,14 +332,24 @@ static int ad7949_spi_init(struct ad7949_adc_chip *ad7949_adc) > > return ret; > > } > > > > +static void ad7949_disable_reg(void *reg) > > +{ > > + regulator_disable(reg); > > +} > > + > > static int ad7949_spi_probe(struct spi_device *spi) > > { > > u32 spi_ctrl_mask = spi->controller->bits_per_word_mask; > > struct device *dev = &spi->dev; > > const struct ad7949_adc_spec *spec; > > struct ad7949_adc_chip *ad7949_adc; > > + struct ad7949_channel *ad7949_chan; > > + struct device_node *child; > > struct iio_dev *indio_dev; > > + int mode; > > + u32 tmp; > > int ret; > > + int i; > > > > indio_dev = devm_iio_device_alloc(dev, sizeof(*ad7949_adc)); > > if (!indio_dev) { > > @@ -343,16 +383,75 @@ static int ad7949_spi_probe(struct spi_device *spi) > > return -EINVAL; > > } > > > > - ad7949_adc->vref = devm_regulator_get(dev, "vref"); > > + /* Setup external voltage ref, buffered? */ > > + ad7949_adc->vref = devm_regulator_get(dev, "vrefin"); > > if (IS_ERR(ad7949_adc->vref)) { > > - dev_err(dev, "fail to request regulator\n"); > > - return PTR_ERR(ad7949_adc->vref); > > + /* unbuffered? */ > > + ad7949_adc->vref = devm_regulator_get(dev, "vref"); > > + if (IS_ERR(ad7949_adc->vref)) { > > + /* Internal then */ > > + mode = AD7949_CFG_VAL_REF_INT_4096; > > + } > > + mode = AD7949_CFG_VAL_REF_EXT_TEMP; > > } > > + mode = AD7949_CFG_VAL_REF_EXT_TEMP_BUF; > > > > - ret = regulator_enable(ad7949_adc->vref); > > - if (ret < 0) { > > - dev_err(dev, "fail to enable regulator\n"); > > - return ret; > > + if (mode > AD7949_CFG_VAL_REF_INT_4096) { > > Range checks on enum values are always rather messy. So > better to explicitly match the cases that matter. > Understood, I'll use AD7949_CFG_VAL_REF_EXTERNAL instead. > > + ret = regulator_enable(ad7949_adc->vref); > > + if (ret < 0) { > > + dev_err(dev, "fail to enable regulator\n"); > > + return ret; > > + } > > + > > + ret = devm_add_action_or_reset(dev, ad7949_disable_reg, > > + ad7949_adc->vref); > > + if (ret) > > + return ret; > > + } > > + > > + ad7949_adc->channels = devm_kcalloc(dev, spec->num_channels, > > + sizeof(*ad7949_adc->channels), > > + GFP_KERNEL); > > + if (!ad7949_adc->channels) { > > + dev_err(dev, "unable to allocate ADC channels\n"); > > + return -ENOMEM; > > + } > > + > > + /* Initialize all channel structures */ > > + for (i = 0; i < spec->num_channels; i++) { > > + ad7949_adc->channels[i].refsel = mode; > > Kernel style is no brackets when only one item in a block. > > > + } > > + > > + /* Read channel specific information form the devicetree */ > > + for_each_child_of_node(dev->of_node, child) { > > + ret = of_property_read_u32(child, "reg", &i); > > + if (ret) { > > + dev_err(dev, "missing reg property in child: %s\n", > > + child->full_name); > > + of_node_put(child); > > + return ret; > > + } > > + > > + ad7949_chan = &ad7949_adc->channels[i]; > > + > > + ret = of_property_read_u32(child, "adi,internal-ref-mv", &tmp); > > Preference for generic device firmware properties not of_* specific > ones. > > I think there is nothing stopping this driver being probed from ACPI via > PRP0001 > before this change. Note you'll also need fwnode_for_each_child_node() > above. > will do. > > + if (ret < 0 && ret != -EINVAL) { > > + of_node_put(child); > > + return ret; > > + } > > + > > + switch (tmp) { > > + case 2500: > > + ad7949_chan->refsel = AD7949_CFG_VAL_REF_INT_2500; > > + break; > > + case 4096: > > + ad7949_chan->refsel = AD7949_CFG_VAL_REF_INT_4096; > > + break; > > + default: > > + dev_err(dev, "unsupported internal voltage reference\n"); > > + of_node_put(child); > > + return -EINVAL; > > + } > > } > > > > mutex_init(&ad7949_adc->lock); > > @@ -373,7 +472,6 @@ static int ad7949_spi_probe(struct spi_device *spi) > > > > err: > > mutex_destroy(&ad7949_adc->lock); > > - regulator_disable(ad7949_adc->vref); > > > > return ret; > > } > > @@ -385,7 +483,6 @@ static int ad7949_spi_remove(struct spi_device *spi) > > > > iio_device_unregister(indio_dev); > > mutex_destroy(&ad7949_adc->lock); > > - regulator_disable(ad7949_adc->vref); > > Given mutex_destroy is mostly pointless (and definitely is here) that > leaves us with just iio_device_register(). Hence if you could do > a follow up patch finishing conversion of this to entirely devm managed > that would be a nice addition to this series (or separate patch is fine > as well). > Sure, I'll add that cleanup in the next revision. Thanks, Liam > > > > return 0; > > }
diff --git a/drivers/iio/adc/ad7949.c b/drivers/iio/adc/ad7949.c index 65f78751225b..8b78da7ead36 100644 --- a/drivers/iio/adc/ad7949.c +++ b/drivers/iio/adc/ad7949.c @@ -36,7 +36,11 @@ /* REF: reference/buffer selection */ #define AD7949_CFG_BIT_REF GENMASK(5, 3) -#define AD7949_CFG_VAL_REF_EXT_BUF 7 +#define AD7949_CFG_VAL_REF_EXT_TEMP_BUF 3 +#define AD7949_CFG_VAL_REF_EXT_TEMP 2 +#define AD7949_CFG_VAL_REF_INT_4096 1 +#define AD7949_CFG_VAL_REF_INT_2500 0 +#define AD7949_CFG_VAL_REF_EXTERNAL BIT(1) /* SEQ: channel sequencer. Allows for scanning channels */ #define AD7949_CFG_BIT_SEQ GENMASK(2, 1) @@ -61,6 +65,14 @@ static const struct ad7949_adc_spec ad7949_adc_spec[] = { [ID_AD7689] = { .num_channels = 8, .resolution = 16 }, }; +/** + * struct ad7949_channel - ADC Channel parameters + * @refsel: reference selection + */ +struct ad7949_channel { + u32 refsel; +}; + /** * struct ad7949_adc_chip - AD ADC chip * @lock: protects write sequences @@ -78,6 +90,7 @@ struct ad7949_adc_chip { struct regulator *vref; struct iio_dev *indio_dev; struct spi_device *spi; + struct ad7949_channel *channels; u8 resolution; u8 bits_per_word; u16 cfg; @@ -138,6 +151,7 @@ static int ad7949_spi_read_channel(struct ad7949_adc_chip *ad7949_adc, int *val, int i; u8 buf8[2]; struct spi_message msg; + struct ad7949_channel ad7949_chan = ad7949_adc->channels[channel]; struct spi_transfer tx[] = { { .rx_buf = &ad7949_adc->buffer, @@ -154,8 +168,9 @@ static int ad7949_spi_read_channel(struct ad7949_adc_chip *ad7949_adc, int *val, */ for (i = 0; i < 2; i++) { ret = ad7949_spi_write_cfg(ad7949_adc, - FIELD_PREP(AD7949_CFG_BIT_INX, channel), - AD7949_CFG_BIT_INX); + FIELD_PREP(AD7949_CFG_BIT_INX, channel) | + FIELD_PREP(AD7949_CFG_BIT_REF, ad7949_chan.refsel), + AD7949_CFG_BIT_INX | AD7949_CFG_BIT_REF); if (ret) return ret; if (channel == ad7949_adc->current_channel) @@ -225,6 +240,7 @@ static int ad7949_spi_read_raw(struct iio_dev *indio_dev, int *val, int *val2, long mask) { struct ad7949_adc_chip *ad7949_adc = iio_priv(indio_dev); + struct ad7949_channel ad7949_chan = ad7949_adc->channels[chan->channel]; int ret; if (!val) @@ -242,12 +258,26 @@ static int ad7949_spi_read_raw(struct iio_dev *indio_dev, return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: - ret = regulator_get_voltage(ad7949_adc->vref); - if (ret < 0) - return ret; + switch (ad7949_chan.refsel) { + case AD7949_CFG_VAL_REF_INT_2500: + *val = 2500; + break; + case AD7949_CFG_VAL_REF_INT_4096: + *val = 4096; + break; + case AD7949_CFG_VAL_REF_EXT_TEMP: + case AD7949_CFG_VAL_REF_EXT_TEMP_BUF: + ret = regulator_get_voltage(ad7949_adc->vref); + if (ret < 0) + return ret; + + /* convert value back to mV */ + *val = ret / 1000; + break; + } - *val = ret / 5000; - return IIO_VAL_INT; + *val2 = (1 << ad7949_adc->resolution) - 1; + return IIO_VAL_FRACTIONAL; } return -EINVAL; @@ -286,7 +316,7 @@ static int ad7949_spi_init(struct ad7949_adc_chip *ad7949_adc) FIELD_PREP(AD7949_CFG_BIT_INCC, AD7949_CFG_VAL_INCC_UNIPOLAR_GND) | FIELD_PREP(AD7949_CFG_BIT_INX, ad7949_adc->current_channel) | FIELD_PREP(AD7949_CFG_BIT_BW_FULL, 1) | - FIELD_PREP(AD7949_CFG_BIT_REF, AD7949_CFG_VAL_REF_EXT_BUF) | + FIELD_PREP(AD7949_CFG_BIT_REF, ad7949_adc->channels[0].refsel) | FIELD_PREP(AD7949_CFG_BIT_SEQ, 0x0) | FIELD_PREP(AD7949_CFG_BIT_RBN, 1); @@ -302,14 +332,24 @@ static int ad7949_spi_init(struct ad7949_adc_chip *ad7949_adc) return ret; } +static void ad7949_disable_reg(void *reg) +{ + regulator_disable(reg); +} + static int ad7949_spi_probe(struct spi_device *spi) { u32 spi_ctrl_mask = spi->controller->bits_per_word_mask; struct device *dev = &spi->dev; const struct ad7949_adc_spec *spec; struct ad7949_adc_chip *ad7949_adc; + struct ad7949_channel *ad7949_chan; + struct device_node *child; struct iio_dev *indio_dev; + int mode; + u32 tmp; int ret; + int i; indio_dev = devm_iio_device_alloc(dev, sizeof(*ad7949_adc)); if (!indio_dev) { @@ -343,16 +383,75 @@ static int ad7949_spi_probe(struct spi_device *spi) return -EINVAL; } - ad7949_adc->vref = devm_regulator_get(dev, "vref"); + /* Setup external voltage ref, buffered? */ + ad7949_adc->vref = devm_regulator_get(dev, "vrefin"); if (IS_ERR(ad7949_adc->vref)) { - dev_err(dev, "fail to request regulator\n"); - return PTR_ERR(ad7949_adc->vref); + /* unbuffered? */ + ad7949_adc->vref = devm_regulator_get(dev, "vref"); + if (IS_ERR(ad7949_adc->vref)) { + /* Internal then */ + mode = AD7949_CFG_VAL_REF_INT_4096; + } + mode = AD7949_CFG_VAL_REF_EXT_TEMP; } + mode = AD7949_CFG_VAL_REF_EXT_TEMP_BUF; - ret = regulator_enable(ad7949_adc->vref); - if (ret < 0) { - dev_err(dev, "fail to enable regulator\n"); - return ret; + if (mode > AD7949_CFG_VAL_REF_INT_4096) { + ret = regulator_enable(ad7949_adc->vref); + if (ret < 0) { + dev_err(dev, "fail to enable regulator\n"); + return ret; + } + + ret = devm_add_action_or_reset(dev, ad7949_disable_reg, + ad7949_adc->vref); + if (ret) + return ret; + } + + ad7949_adc->channels = devm_kcalloc(dev, spec->num_channels, + sizeof(*ad7949_adc->channels), + GFP_KERNEL); + if (!ad7949_adc->channels) { + dev_err(dev, "unable to allocate ADC channels\n"); + return -ENOMEM; + } + + /* Initialize all channel structures */ + for (i = 0; i < spec->num_channels; i++) { + ad7949_adc->channels[i].refsel = mode; + } + + /* Read channel specific information form the devicetree */ + for_each_child_of_node(dev->of_node, child) { + ret = of_property_read_u32(child, "reg", &i); + if (ret) { + dev_err(dev, "missing reg property in child: %s\n", + child->full_name); + of_node_put(child); + return ret; + } + + ad7949_chan = &ad7949_adc->channels[i]; + + ret = of_property_read_u32(child, "adi,internal-ref-mv", &tmp); + if (ret < 0 && ret != -EINVAL) { + of_node_put(child); + return ret; + } + + switch (tmp) { + case 2500: + ad7949_chan->refsel = AD7949_CFG_VAL_REF_INT_2500; + break; + case 4096: + ad7949_chan->refsel = AD7949_CFG_VAL_REF_INT_4096; + break; + default: + dev_err(dev, "unsupported internal voltage reference\n"); + of_node_put(child); + return -EINVAL; + } } mutex_init(&ad7949_adc->lock); @@ -373,7 +472,6 @@ static int ad7949_spi_probe(struct spi_device *spi) err: mutex_destroy(&ad7949_adc->lock); - regulator_disable(ad7949_adc->vref); return ret; } @@ -385,7 +483,6 @@ static int ad7949_spi_remove(struct spi_device *spi) iio_device_unregister(indio_dev); mutex_destroy(&ad7949_adc->lock); - regulator_disable(ad7949_adc->vref); return 0; }