On Wed, 10 Jan 2024 13:58:07 +0100 Mårten Lindahl <marten.lindahl@xxxxxxxx> wrote: > The vcnl4040/vcnl4200 proximity sensor defaults to 12 bit data > resolution, but the chip also supports 16 bit data resolution, which is > called proximity high definition (PS_HD). > > Make the vcnl4040/vcnl4200 proximity sensor use the high definition for > all data readings. Please note that in order to preserve the 12 bit > integer part of the in_proximity_raw output, the format is changed from > integer to fixed point. > > Signed-off-by: Mårten Lindahl <marten.lindahl@xxxxxxxx> Hi Mårten, I don't understand why we'd try to carry on with using the device if the additional register accesses fail. Just fail the probe, the hardware is broken. Jonathan > --- > Changes in v2: > - Update registers for sample rate to align it with 16 bit sensor readings. > - Change sysfs output from IIO_VAL_INT to IIO_VAL_FRACTIONAL and scale by 16. > - Link to v1: https://lore.kernel.org/r/20231221-vcnl4000-ps-hd-v1-1-a024bfb28896@xxxxxxxx > --- > drivers/iio/light/vcnl4000.c | 40 +++++++++++++++++++++++++++++++++++++++- > 1 file changed, 39 insertions(+), 1 deletion(-) > > diff --git a/drivers/iio/light/vcnl4000.c b/drivers/iio/light/vcnl4000.c > index fdf763a04b0b..a078c573131e 100644 > --- a/drivers/iio/light/vcnl4000.c > +++ b/drivers/iio/light/vcnl4000.c > @@ -90,6 +90,7 @@ > #define VCNL4040_PS_CONF1_PS_SHUTDOWN BIT(0) > #define VCNL4040_PS_CONF2_PS_IT GENMASK(3, 1) /* Proximity integration time */ > #define VCNL4040_CONF1_PS_PERS GENMASK(5, 4) /* Proximity interrupt persistence setting */ > +#define VCNL4040_PS_CONF2_PS_HD BIT(11) /* Proximity high definition */ > #define VCNL4040_PS_CONF2_PS_INT GENMASK(9, 8) /* Proximity interrupt mode */ > #define VCNL4040_PS_CONF3_MPS GENMASK(6, 5) /* Proximity multi pulse number */ > #define VCNL4040_PS_MS_LED_I GENMASK(10, 8) /* Proximity current */ > @@ -114,6 +115,13 @@ > #define VCNL4010_INT_DRDY \ > (BIT(VCNL4010_INT_PROXIMITY) | BIT(VCNL4010_INT_ALS)) > > +#define VCNL4040_CONF3_PS_MPS_16BITS 3 /* 8 multi pulses */ > +#define VCNL4040_CONF3_PS_LED_I_16BITS 3 /* 120 mA */ > + > +#define VCNL4040_CONF3_PS_SAMPLE_16BITS \ > + (FIELD_PREP(VCNL4040_PS_CONF3_MPS, VCNL4040_CONF3_PS_MPS_16BITS) | \ > + FIELD_PREP(VCNL4040_PS_MS_LED_I, VCNL4040_CONF3_PS_LED_I_16BITS)) > + > static const int vcnl4010_prox_sampling_frequency[][2] = { > {1, 950000}, > {3, 906250}, > @@ -195,6 +203,7 @@ struct vcnl4000_data { > enum vcnl4000_device_ids id; > int rev; > int al_scale; > + int ps_scale; > u8 ps_int; /* proximity interrupt mode */ > u8 als_int; /* ambient light interrupt mode*/ > const struct vcnl4000_chip_spec *chip_spec; > @@ -345,6 +354,7 @@ static int vcnl4200_set_power_state(struct vcnl4000_data *data, bool on) > static int vcnl4200_init(struct vcnl4000_data *data) > { > int ret, id; > + u16 regval; > > ret = i2c_smbus_read_word_data(data->client, VCNL4200_DEV_ID); > if (ret < 0) > @@ -386,9 +396,36 @@ static int vcnl4200_init(struct vcnl4000_data *data) > break; > } > data->al_scale = data->chip_spec->ulux_step; > + data->ps_scale = 16; > mutex_init(&data->vcnl4200_al.lock); > mutex_init(&data->vcnl4200_ps.lock); > > + /* Use 16 bits proximity sensor readings */ > + ret = i2c_smbus_read_word_data(data->client, VCNL4200_PS_CONF1); > + if (ret >= 0) { > + regval = (ret | VCNL4040_PS_CONF2_PS_HD); Trivial but those brackets are unnecessary. > + ret = i2c_smbus_write_word_data(data->client, VCNL4200_PS_CONF1, > + regval); > + } > + > + if (ret < 0) { > + dev_info(&data->client->dev, "Default to 12 bits sensor data"); Silly question - how can we get here? If it's a case of a read or a write failing then that's a critical failure and we have very little idea what the state is. If that happens I'd just fail to probe the driver rather than carrying on with 12 bit assumed. > + data->ps_scale = 1; > + goto out; > + } > + > + /* Align proximity sensor sample rate to 16 bits data width */ > + ret = i2c_smbus_read_word_data(data->client, VCNL4200_PS_CONF3); > + if (ret >= 0) { If the read fails, something is very wrong. Fail the probe. > + regval = (ret | VCNL4040_CONF3_PS_SAMPLE_16BITS); > + ret = i2c_smbus_write_word_data(data->client, VCNL4200_PS_CONF3, > + regval); > + } > + > + if (ret < 0) > + dev_warn(&data->client->dev, "Sample rate may not be accurate"); If this fails, fail the probe. Don't try to carry on anyway. > + > +out: > ret = data->chip_spec->set_power_state(data, true); > if (ret < 0) > return ret; > @@ -901,8 +938,9 @@ static int vcnl4000_read_raw(struct iio_dev *indio_dev, > break; > case IIO_PROXIMITY: > ret = data->chip_spec->measure_proximity(data, val); > + *val2 = data->ps_scale; > if (!ret) > - ret = IIO_VAL_INT; > + ret = IIO_VAL_FRACTIONAL; > break; > default: > ret = -EINVAL; > > --- > base-commit: a39b6ac3781d46ba18193c9dbb2110f31e9bffe9 > change-id: 20231221-vcnl4000-ps-hd-863f4f8fcea7 > > Best regards,
