| Message ID | 20240514120222.56488-4-alisa.roman@analog.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | iio: adc: ad7192: Add AD7194 support | expand |
On Tue, May 14, 2024 at 03:02:19PM +0300, Alisa-Dariana Roman wrote: > AINCOM should actually be a supply. AINx inputs are referenced to AINCOM > in pseudo-differential operation mode. AINCOM voltage represents the > offset of corresponding channels. ... Possible cleanup with the help of struct device *dev = &spi->dev; > struct ad7192_state *st; > struct iio_dev *indio_dev; > + struct regulator *aincom; > int ret; ... > + aincom = devm_regulator_get_optional(&spi->dev, "aincom"); aincom = devm_regulator_get_optional(dev, "aincom"); ... > + return dev_err_probe(&spi->dev, PTR_ERR(aincom), > + "Failed to get AINCOM supply\n"); return dev_err_probe(dev, PTR_ERR(aincom), "Failed to get AINCOM supply\n"); ... > + return dev_err_probe(&spi->dev, ret, > + "Failed to enable specified AINCOM supply\n"); return dev_err_probe(dev, ret, "Failed to enable specified AINCOM supply\n"); ... > + ret = devm_add_action_or_reset(&spi->dev, ad7192_reg_disable, aincom); ret = devm_add_action_or_reset(dev, ad7192_reg_disable, aincom); ... > + return dev_err_probe(&spi->dev, ret, > + "Device tree error, AINCOM voltage undefined\n"); return dev_err_probe(dev, ret, "Device tree error, AINCOM voltage undefined\n");
On Tue, 14 May 2024 16:13:05 +0300 Andy Shevchenko <andy@kernel.org> wrote: > On Tue, May 14, 2024 at 03:02:19PM +0300, Alisa-Dariana Roman wrote: > > AINCOM should actually be a supply. AINx inputs are referenced to AINCOM > > in pseudo-differential operation mode. AINCOM voltage represents the > > offset of corresponding channels. > > ... > > Possible cleanup with the help of > > struct device *dev = &spi->dev; This is a good thing to have as a follow up as it applies much more widely than what is visible in this patch. In ideal world it would have been a precursor to this series, but I don't want to delay this for a v9 just to add that. Hence I'm not going to tweak this whilst applying. Patch applied as is. Thanks, Jonathan > > > > struct ad7192_state *st; > > struct iio_dev *indio_dev; > > + struct regulator *aincom; > > int ret; > > ... > > > + aincom = devm_regulator_get_optional(&spi->dev, "aincom"); > > aincom = devm_regulator_get_optional(dev, "aincom"); > > ... > > > + return dev_err_probe(&spi->dev, PTR_ERR(aincom), > > + "Failed to get AINCOM supply\n"); > > return dev_err_probe(dev, PTR_ERR(aincom), > "Failed to get AINCOM supply\n"); > > ... > > > + return dev_err_probe(&spi->dev, ret, > > + "Failed to enable specified AINCOM supply\n"); > > return dev_err_probe(dev, ret, > "Failed to enable specified AINCOM supply\n"); > > ... > > > + ret = devm_add_action_or_reset(&spi->dev, ad7192_reg_disable, aincom); > > ret = devm_add_action_or_reset(dev, ad7192_reg_disable, aincom); > > ... > > > + return dev_err_probe(&spi->dev, ret, > > + "Device tree error, AINCOM voltage undefined\n"); > > return dev_err_probe(dev, ret, > "Device tree error, AINCOM voltage undefined\n"); >
diff --git a/drivers/iio/adc/ad7192.c b/drivers/iio/adc/ad7192.c index ace81e3817a1..7160929d32c9 100644 --- a/drivers/iio/adc/ad7192.c +++ b/drivers/iio/adc/ad7192.c @@ -20,6 +20,7 @@ #include <linux/module.h> #include <linux/mod_devicetable.h> #include <linux/property.h> +#include <linux/units.h> #include <linux/iio/iio.h> #include <linux/iio/sysfs.h> @@ -186,6 +187,7 @@ struct ad7192_state { struct regulator *vref; struct clk *mclk; u16 int_vref_mv; + u32 aincom_mv; u32 fclk; u32 mode; u32 conf; @@ -742,10 +744,24 @@ static int ad7192_read_raw(struct iio_dev *indio_dev, *val = -(1 << (chan->scan_type.realbits - 1)); else *val = 0; + + switch (chan->type) { + case IIO_VOLTAGE: + /* + * Only applies to pseudo-differential inputs. + * AINCOM voltage has to be converted to "raw" units. + */ + if (st->aincom_mv && !chan->differential) + *val += DIV_ROUND_CLOSEST_ULL((u64)st->aincom_mv * NANO, + st->scale_avail[gain][1]); + return IIO_VAL_INT; /* Kelvin to Celsius */ - if (chan->type == IIO_TEMP) + case IIO_TEMP: *val -= 273 * ad7192_get_temp_scale(unipolar); - return IIO_VAL_INT; + return IIO_VAL_INT; + default: + return -EINVAL; + } case IIO_CHAN_INFO_SAMP_FREQ: *val = DIV_ROUND_CLOSEST(ad7192_get_f_adc(st), 1024); return IIO_VAL_INT; @@ -1052,6 +1068,7 @@ static int ad7192_probe(struct spi_device *spi) { struct ad7192_state *st; struct iio_dev *indio_dev; + struct regulator *aincom; int ret; if (!spi->irq) { @@ -1067,6 +1084,35 @@ static int ad7192_probe(struct spi_device *spi) mutex_init(&st->lock); + /* + * Regulator aincom is optional to maintain compatibility with older DT. + * Newer firmware should provide a zero volt fixed supply if wired to + * ground. + */ + aincom = devm_regulator_get_optional(&spi->dev, "aincom"); + if (IS_ERR(aincom)) { + if (PTR_ERR(aincom) != -ENODEV) + return dev_err_probe(&spi->dev, PTR_ERR(aincom), + "Failed to get AINCOM supply\n"); + + st->aincom_mv = 0; + } else { + ret = regulator_enable(aincom); + if (ret) + return dev_err_probe(&spi->dev, ret, + "Failed to enable specified AINCOM supply\n"); + + ret = devm_add_action_or_reset(&spi->dev, ad7192_reg_disable, aincom); + if (ret) + return ret; + + ret = regulator_get_voltage(aincom); + if (ret < 0) + return dev_err_probe(&spi->dev, ret, + "Device tree error, AINCOM voltage undefined\n"); + st->aincom_mv = ret / MILLI; + } + st->avdd = devm_regulator_get(&spi->dev, "avdd"); if (IS_ERR(st->avdd)) return PTR_ERR(st->avdd);
AINCOM should actually be a supply. AINx inputs are referenced to AINCOM in pseudo-differential operation mode. AINCOM voltage represents the offset of corresponding channels. Signed-off-by: Alisa-Dariana Roman <alisa.roman@analog.com> --- drivers/iio/adc/ad7192.c | 50 ++++++++++++++++++++++++++++++++++++++-- 1 file changed, 48 insertions(+), 2 deletions(-)