LinuxLists.cc - [PATCH v2 0/9] Add support for AD411x

[permalink] [raw]

Subject: [PATCH v2 1/9] dt-bindings: adc: ad7173: add support for ad411x

From: Dumitru Ceclan <[email protected]>

Add support for: AD4111, AD4112, AD4114, AD4115, AD4116.

AD411x family ADCs support a VCOM pin, dedicated for single-ended usage.
AD4111/AD4112 support current channels, usage is implemented by
specifying channel reg values bigger than 15.

Signed-off-by: Dumitru Ceclan <[email protected]>
---
.../devicetree/bindings/iio/adc/adi,ad7173.yaml | 118 ++++++++++++++++++++-
1 file changed, 117 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
index ea6cfcd0aff4..6cc3514f5ed8 100644
--- a/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
@@ -19,7 +19,18 @@ description: |
primarily for measurement of signals close to DC but also delivers
outstanding performance with input bandwidths out to ~10kHz.

+ Analog Devices AD411x ADC's:
+ The AD411X family encompasses a series of low power, low noise, 24-bit,
+ sigma-delta analog-to-digital converters that offer a versatile range of
+ specifications. They integrate an analog front end suitable for processing
+ fully differential/single-ended and bipolar voltage inputs.
+
Datasheets for supported chips:
+ https://www.analog.com/media/en/technical-documentation/data-sheets/AD4111.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/AD4112.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/AD4114.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/AD4115.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/AD4116.pdf
https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-2.pdf
https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-4.pdf
https://www.analog.com/media/en/technical-documentation/data-sheets/AD7173-8.pdf
@@ -31,6 +42,11 @@ description: |
properties:
compatible:
enum:
+ - adi,ad4111
+ - adi,ad4112
+ - adi,ad4114
+ - adi,ad4115
+ - adi,ad4116
- adi,ad7172-2
- adi,ad7172-4
- adi,ad7173-8
@@ -129,6 +145,31 @@ patternProperties:
maximum: 15

diff-channels:
+ description: |
+ For using current channels specify select the current inputs
+ and enable the adi,current-channel property.
+
+ Family AD411x supports a dedicated VCOM voltage input.
+ To select it set the second channel to 16.
+ (VIN2, VCOM) -> diff-channels = <2 16>
+
+ There are special values that can be selected besides the voltage
+ analog inputs:
+ 21: REF+
+ 22: REF−
+ Supported only by AD7172-2, AD7172-4, AD7175-2, AD7175-8, AD7177-2:
+ 19: ((AVDD1 − AVSS)/5)+
+ 20: ((AVDD1 − AVSS)/5)−
+ Supported only by AD4111, AD4112:
+ 12: IIN3+
+ 11: IIN3−
+ 13: IIN2+
+ 10: IIN2−
+ 14: IIN1+
+ 9: IIN1−
+ 15: IIN0+
+ 8: IIN0−
+
items:
minimum: 0
maximum: 31
@@ -154,6 +195,23 @@ patternProperties:
- avdd
default: refout-avss

+ adi,current-channel:
+ description: |
+ Signal that the selected inputs are current channels.
+ Only available on AD4111 and AD4112.
+ type: boolean
+
+ adi,channel-type:
+ description:
+ Used to differentiate between different channel types as the device
+ register configurations are the same for all usage types.
+ $ref: /schemas/types.yaml#/definitions/string
+ enum:
+ - single-ended
+ - pseudo-differential
+ - differential
+ default: differential
+
required:
- reg
- diff-channels
@@ -166,7 +224,6 @@ allOf:
- $ref: /schemas/spi/spi-peripheral-props.yaml#

# Only ad7172-4, ad7173-8 and ad7175-8 support vref2
- # Other models have [0-3] channel registers
- if:
properties:
compatible:
@@ -187,6 +244,37 @@ allOf:
- vref
- refout-avss
- avdd
+
+ - if:
+ properties:
+ compatible:
+ contains:
+ enum:
+ - adi,ad4114
+ - adi,ad4115
+ - adi,ad4116
+ - adi,ad7173-8
+ - adi,ad7175-8
+ then:
+ patternProperties:
+ "^channel@[0-9a-f]$":
+ properties:
+ reg:
+ maximum: 15
+
+ - if:
+ properties:
+ compatible:
+ contains:
+ enum:
+ - adi,ad7172-2
+ - adi,ad7175-2
+ - adi,ad7176-2
+ - adi,ad7177-2
+ then:
+ patternProperties:
+ "^channel@[0-9a-f]$":
+ properties:
reg:
maximum: 3

@@ -210,6 +298,34 @@ allOf:
required:
- adi,reference-select

+ - if:
+ properties:
+ compatible:
+ contains:
+ enum:
+ - adi,ad4111
+ - adi,ad4112
+ - adi,ad4114
+ - adi,ad4115
+ - adi,ad4116
+ then:
+ properties:
+ avdd2-supply: false
+
+ - if:
+ properties:
+ compatible:
+ not:
+ contains:
+ enum:
+ - adi,ad4111
+ - adi,ad4112
+ then:
+ patternProperties:
+ "^channel@[0-9a-f]$":
+ properties:
+ adi,current-channel: false
+
- if:
anyOf:
- required: [clock-names]

--
2.43.0

2024-05-14 07:24:49

[permalink] [raw]

Subject: [PATCH v2 3/9] iio: adc: ad7173: refactor channel configuration parsing

From: Dumitru Ceclan <[email protected]>

Move configurations regarding number of channels from
*_fw_parse_device_config to *_fw_parse_channel_config.

Suggested-by: Jonathan Cameron <[email protected]>
Link: https://lore.kernel.org/all/20240303162148.3ad91aa2@jic23-huawei/

Reviewed-by: David Lechner <[email protected]>
Signed-off-by: Dumitru Ceclan <[email protected]>
---
drivers/iio/adc/ad7173.c | 29 +++++++++++++++++------------
1 file changed, 17 insertions(+), 12 deletions(-)

diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
index 850574437bda..d5ad3f01dec7 100644
--- a/drivers/iio/adc/ad7173.c
+++ b/drivers/iio/adc/ad7173.c
@@ -918,7 +918,23 @@ static int ad7173_fw_parse_channel_config(struct iio_dev *indio_dev)
struct device *dev = indio_dev->dev.parent;
struct iio_chan_spec *chan_arr, *chan;
unsigned int ain[2], chan_index = 0;
- int ref_sel, ret;
+ int ref_sel, ret, num_channels;
+
+ num_channels = device_get_child_node_count(dev);
+
+ if (st->info->has_temp)
+ num_channels++;
+
+ if (num_channels == 0)
+ return dev_err_probe(dev, -ENODATA, "No channels specified\n");
+
+ if (num_channels > st->info->num_channels)
+ return dev_err_probe(dev, -EINVAL,
+ "Too many channels specified. Maximum is %d, not including temperature channel if supported.\n",
+ st->info->num_channels);
+
+ indio_dev->num_channels = num_channels;
+ st->num_channels = num_channels;

chan_arr = devm_kcalloc(dev, sizeof(*indio_dev->channels),
st->num_channels, GFP_KERNEL);
@@ -1013,7 +1029,6 @@ static int ad7173_fw_parse_device_config(struct iio_dev *indio_dev)
{
struct ad7173_state *st = iio_priv(indio_dev);
struct device *dev = indio_dev->dev.parent;
- unsigned int num_channels;
int ret;

st->regulators[0].supply = ad7173_ref_sel_str[AD7173_SETUP_REF_SEL_EXT_REF];
@@ -1072,16 +1087,6 @@ static int ad7173_fw_parse_device_config(struct iio_dev *indio_dev)

ad7173_sigma_delta_info.irq_line = ret;

- num_channels = device_get_child_node_count(dev);
-
- if (st->info->has_temp)
- num_channels++;
-
- if (num_channels == 0)
- return dev_err_probe(dev, -ENODATA, "No channels specified\n");
- indio_dev->num_channels = num_channels;
- st->num_channels = num_channels;
-
return ad7173_fw_parse_channel_config(indio_dev);
}

--
2.43.0

2024-05-14 07:24:49

[permalink] [raw]

Subject: [PATCH v2 5/9] iio: adc: ad7173: add support for special inputs

From: Dumitru Ceclan <[email protected]>

Add support for selecting REF+ and REF- inputs on all models.
Add support for selecting ((AVDD1 − AVSS)/5) inputs
on supported models.

Signed-off-by: Dumitru Ceclan <[email protected]>
---
drivers/iio/adc/ad7173.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)

diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
index fb33534d63a9..1e9ba3070770 100644
--- a/drivers/iio/adc/ad7173.c
+++ b/drivers/iio/adc/ad7173.c
@@ -65,6 +65,10 @@
FIELD_PREP(AD7173_CH_SETUP_AINNEG_MASK, neg))
#define AD7173_AIN_TEMP_POS 17
#define AD7173_AIN_TEMP_NEG 18
+#define AD7173_AIN_COM_IN_POS 19
+#define AD7173_AIN_COM_IN_NEG 20
+#define AD7173_AIN_REF_POS 21
+#define AD7173_AIN_REF_NEG 22

#define AD7172_2_ID 0x00d0
#define AD7175_ID 0x0cd0
@@ -145,6 +149,8 @@ struct ad7173_device_info {
unsigned int id;
char *name;
bool has_temp;
+ /* ((AVDD1 − AVSS)/5) */
+ bool has_common_input;
bool has_input_buf;
bool has_int_ref;
bool has_ref2;
@@ -215,6 +221,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
.has_temp = true,
.has_input_buf = true,
.has_int_ref = true,
+ .has_common_input = true,
.clock = 2 * HZ_PER_MHZ,
.sinc5_data_rates = ad7173_sinc5_data_rates,
.num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
@@ -228,6 +235,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
.has_temp = false,
.has_input_buf = true,
.has_ref2 = true,
+ .has_common_input = true,
.clock = 2 * HZ_PER_MHZ,
.sinc5_data_rates = ad7173_sinc5_data_rates,
.num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
@@ -243,6 +251,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
.has_input_buf = true,
.has_int_ref = true,
.has_ref2 = true,
+ .has_common_input = false,
.clock = 2 * HZ_PER_MHZ,
.sinc5_data_rates = ad7173_sinc5_data_rates,
.num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
@@ -257,6 +266,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
.has_temp = true,
.has_input_buf = true,
.has_int_ref = true,
+ .has_common_input = true,
.clock = 16 * HZ_PER_MHZ,
.sinc5_data_rates = ad7175_sinc5_data_rates,
.num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
@@ -271,6 +281,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
.has_input_buf = true,
.has_int_ref = true,
.has_ref2 = true,
+ .has_common_input = true,
.clock = 16 * HZ_PER_MHZ,
.sinc5_data_rates = ad7175_sinc5_data_rates,
.num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
@@ -285,6 +296,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
.has_temp = false,
.has_input_buf = false,
.has_int_ref = true,
+ .has_common_input = false,
.clock = 16 * HZ_PER_MHZ,
.sinc5_data_rates = ad7175_sinc5_data_rates,
.num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
@@ -298,6 +310,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
.has_temp = true,
.has_input_buf = true,
.has_int_ref = true,
+ .has_common_input = true,
.clock = 16 * HZ_PER_MHZ,
.odr_start_value = AD7177_ODR_START_VALUE,
.sinc5_data_rates = ad7175_sinc5_data_rates,
@@ -920,6 +933,14 @@ static int ad7173_validate_voltage_ain_inputs(struct ad7173_state *st,
if (ain[i] < st->info->num_inputs)
continue;

+ if (ain[i] == AD7173_AIN_REF_POS || ain[i] == AD7173_AIN_REF_NEG)
+ continue;
+
+ if ((ain[i] == AD7173_AIN_COM_IN_POS ||
+ ain[i] == AD7173_AIN_COM_IN_NEG) &&
+ st->info->has_common_input)
+ continue;
+
return dev_err_probe(dev, -EINVAL,
"Input pin number out of range for pair (%d %d).\n",
ain[0], ain[1]);

--
2.43.0

2024-05-14 07:24:49

[permalink] [raw]

Subject: [PATCH v2 4/9] iio: adc: ad7173: refactor ain and vref selection

From: Dumitru Ceclan <[email protected]>

Move validation of analog inputs and reference voltage selection to
separate functions to reduce the size of the channel config parsing
function and improve readability.

Signed-off-by: Dumitru Ceclan <[email protected]>
---
drivers/iio/adc/ad7173.c | 62 ++++++++++++++++++++++++++++++++++--------------
1 file changed, 44 insertions(+), 18 deletions(-)

diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
index d5ad3f01dec7..fb33534d63a9 100644
--- a/drivers/iio/adc/ad7173.c
+++ b/drivers/iio/adc/ad7173.c
@@ -911,6 +911,44 @@ static int ad7173_register_clk_provider(struct iio_dev *indio_dev)
&st->int_clk_hw);
}

+static int ad7173_validate_voltage_ain_inputs(struct ad7173_state *st,
+ unsigned int ain[2])
+{
+ struct device *dev = &st->sd.spi->dev;
+
+ for (int i = 0; i < 2; i++) {
+ if (ain[i] < st->info->num_inputs)
+ continue;
+
+ return dev_err_probe(dev, -EINVAL,
+ "Input pin number out of range for pair (%d %d).\n",
+ ain[0], ain[1]);
+ }
+
+ return 0;
+}
+
+static int ad7173_validate_reference(struct ad7173_state *st, int ref_sel)
+{
+ struct device *dev = &st->sd.spi->dev;
+ int ret;
+
+ if (ref_sel == AD7173_SETUP_REF_SEL_INT_REF && !st->info->has_int_ref)
+ return dev_err_probe(dev, -EINVAL,
+ "Internal reference is not available on current model.\n");
+
+ if (ref_sel == AD7173_SETUP_REF_SEL_EXT_REF2 && !st->info->has_ref2)
+ return dev_err_probe(dev, -EINVAL,
+ "External reference 2 is not available on current model.\n");
+
+ ret = ad7173_get_ref_voltage_milli(st, ref_sel);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "Cannot use reference %u\n",
+ ref_sel);
+
+ return 0;
+}
+
static int ad7173_fw_parse_channel_config(struct iio_dev *indio_dev)
{
struct ad7173_channel *chans_st_arr, *chan_st_priv;
@@ -971,11 +1009,9 @@ static int ad7173_fw_parse_channel_config(struct iio_dev *indio_dev)
if (ret)
return ret;

- if (ain[0] >= st->info->num_inputs ||
- ain[1] >= st->info->num_inputs)
- return dev_err_probe(dev, -EINVAL,
- "Input pin number out of range for pair (%d %d).\n",
- ain[0], ain[1]);
+ ret = ad7173_validate_voltage_ain_inputs(st, ain);
+ if (ret)
+ return ret;

ret = fwnode_property_match_property_string(child,
"adi,reference-select",
@@ -986,19 +1022,9 @@ static int ad7173_fw_parse_channel_config(struct iio_dev *indio_dev)
else
ref_sel = ret;

- if (ref_sel == AD7173_SETUP_REF_SEL_INT_REF &&
- !st->info->has_int_ref)
- return dev_err_probe(dev, -EINVAL,
- "Internal reference is not available on current model.\n");
-
- if (ref_sel == AD7173_SETUP_REF_SEL_EXT_REF2 && !st->info->has_ref2)
- return dev_err_probe(dev, -EINVAL,
- "External reference 2 is not available on current model.\n");
-
- ret = ad7173_get_ref_voltage_milli(st, ref_sel);
- if (ret < 0)
- return dev_err_probe(dev, ret,
- "Cannot use reference %u\n", ref_sel);
+ ret = ad7173_validate_reference(st, ref_sel);
+ if (ret)
+ return ret;

if (ref_sel == AD7173_SETUP_REF_SEL_INT_REF)
st->adc_mode |= AD7173_ADC_MODE_REF_EN;

--
2.43.0

2024-05-14 07:25:01

[permalink] [raw]

Subject: [PATCH v2 6/9] iio: adc: ad7173: Add ad7173_device_info names

From: Dumitru Ceclan <[email protected]>

Add missing names from the device info struct for 3 models to ensure
consistency with the rest of the models.

Signed-off-by: Dumitru Ceclan <[email protected]>
---
drivers/iio/adc/ad7173.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
index 1e9ba3070770..d965b66d4d5a 100644
--- a/drivers/iio/adc/ad7173.c
+++ b/drivers/iio/adc/ad7173.c
@@ -227,6 +227,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
.num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
},
[ID_AD7172_4] = {
+ .name = "ad7172-4",
.id = AD7172_4_ID,
.num_inputs = 9,
.num_channels = 8,
@@ -272,6 +273,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
.num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
},
[ID_AD7175_8] = {
+ .name = "ad7175-8",
.id = AD7175_8_ID,
.num_inputs = 17,
.num_channels = 16,
@@ -302,6 +304,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
.num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
},
[ID_AD7177_2] = {
+ .name = "ad7177-2",
.id = AD7177_ID,
.num_inputs = 5,
.num_channels = 4,

--
2.43.0

2024-05-14 07:25:38

[permalink] [raw]

Subject: [PATCH v2 9/9] iio: adc: ad7173: Reduce device info struct size

From: Dumitru Ceclan <[email protected]>

Reduce the size used by the device info struct by packing the bool
fields within the same byte. This reduces the struct size from 52 bytes
to 44 bytes.

Signed-off-by: Dumitru Ceclan <[email protected]>
---
drivers/iio/adc/ad7173.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
index f049d79380ac..f963c731cae3 100644
--- a/drivers/iio/adc/ad7173.c
+++ b/drivers/iio/adc/ad7173.c
@@ -180,15 +180,15 @@ struct ad7173_device_info {
unsigned int clock;
unsigned int id;
char *name;
- bool has_current_inputs;
- bool has_vcom_input;
- bool has_temp;
+ bool has_current_inputs :1;
+ bool has_vcom_input :1;
+ bool has_temp :1;
/* ((AVDD1 − AVSS)/5) */
- bool has_common_input;
- bool has_input_buf;
- bool has_int_ref;
- bool has_ref2;
- bool higher_gpio_bits;
+ bool has_common_input :1;
+ bool has_input_buf :1;
+ bool has_int_ref :1;
+ bool has_ref2 :1;
+ bool higher_gpio_bits :1;
u8 num_gpios;
};

--
2.43.0

2024-05-14 07:26:03

[permalink] [raw]

Subject: [PATCH v2 8/9] iio: adc: ad7173: Add support for AD411x devices

From: Dumitru Ceclan <[email protected]>

Add support for AD4111/AD4112/AD4114/AD4115/AD4116.

The AD411X family encompasses a series of low power, low noise, 24-bit,
sigma-delta analog-to-digital converters that offer a versatile range of
specifications.

This family of ADCs integrates an analog front end suitable for processing
both fully differential and single-ended, bipolar voltage inputs
addressing a wide array of industrial and instrumentation requirements.

- All ADCs have inputs with a precision voltage divider with a division
ratio of 10.
- AD4116 has 5 low level inputs without a voltage divider.
- AD4111 and AD4112 support current inputs (0 mA to 20 mA) using a 50ohm
shunt resistor.

Signed-off-by: Dumitru Ceclan <[email protected]>
---
drivers/iio/adc/ad7173.c | 316 ++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 288 insertions(+), 28 deletions(-)

diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
index d66b47e1a186..f049d79380ac 100644
--- a/drivers/iio/adc/ad7173.c
+++ b/drivers/iio/adc/ad7173.c
@@ -1,8 +1,9 @@
// SPDX-License-Identifier: GPL-2.0+
/*
- * AD717x family SPI ADC driver
+ * AD717x and AD411x family SPI ADC driver
*
* Supported devices:
+ * AD4111/AD4112/AD4114/AD4115/AD4116
* AD7172-2/AD7172-4/AD7173-8/AD7175-2
* AD7175-8/AD7176-2/AD7177-2
*
@@ -75,7 +76,9 @@
#define AD7176_ID 0x0c90
#define AD7175_2_ID 0x0cd0
#define AD7172_4_ID 0x2050
-#define AD7173_ID 0x30d0
+#define AD7173_AD4111_AD4112_AD4114_ID 0x30d0
+#define AD4116_ID 0x34d0
+#define AD4115_ID 0x38d0
#define AD7175_8_ID 0x3cd0
#define AD7177_ID 0x4fd0
#define AD7173_ID_MASK GENMASK(15, 4)
@@ -106,6 +109,7 @@

#define AD7173_GPO12_DATA(x) BIT((x) + 0)
#define AD7173_GPO23_DATA(x) BIT((x) + 4)
+#define AD4111_GPO01_DATA(x) BIT((x) + 6)
#define AD7173_GPO_DATA(x) ((x) < 2 ? AD7173_GPO12_DATA(x) : AD7173_GPO23_DATA(x))

#define AD7173_INTERFACE_DATA_STAT BIT(6)
@@ -124,11 +128,20 @@
#define AD7173_VOLTAGE_INT_REF_uV 2500000
#define AD7173_TEMP_SENSIIVITY_uV_per_C 477
#define AD7177_ODR_START_VALUE 0x07
+#define AD4111_SHUNT_RESISTOR_OHM 50
+#define AD4111_DIVIDER_RATIO 10
+#define AD411X_VCOM_INPUT 0X10
+#define AD4111_CURRENT_CHAN_CUTOFF 16

#define AD7173_FILTER_ODR0_MASK GENMASK(5, 0)
#define AD7173_MAX_CONFIGS 8

enum ad7173_ids {
+ ID_AD4111,
+ ID_AD4112,
+ ID_AD4114,
+ ID_AD4115,
+ ID_AD4116,
ID_AD7172_2,
ID_AD7172_4,
ID_AD7173_8,
@@ -138,22 +151,44 @@ enum ad7173_ids {
ID_AD7177_2,
};

+enum ad4111_current_channels {
+ AD4111_CURRENT_IN0P_IN0N,
+ AD4111_CURRENT_IN1P_IN1N,
+ AD4111_CURRENT_IN2P_IN2N,
+ AD4111_CURRENT_IN3P_IN3N,
+};
+
+enum ad7173_channel_types {
+ AD7173_CHAN_SINGLE_ENDED,
+ AD7173_CHAN_PSEUDO_DIFFERENTIAL,
+ AD7173_CHAN_DIFFERENTIAL,
+};
+
struct ad7173_device_info {
const unsigned int *sinc5_data_rates;
unsigned int num_sinc5_data_rates;
unsigned int odr_start_value;
+ /*
+ * AD4116 has both inputs with a volage divider and without.
+ * These inputs cannot be mixed in the channel configuration.
+ * Does not include the VCOM input.
+ */
+ unsigned int num_voltage_inputs_with_divider;
unsigned int num_channels;
unsigned int num_configs;
- unsigned int num_inputs;
+ unsigned int num_voltage_inputs;
unsigned int clock;
unsigned int id;
char *name;
+ bool has_current_inputs;
+ bool has_vcom_input;
bool has_temp;
/* ((AVDD1 − AVSS)/5) */
bool has_common_input;
bool has_input_buf;
bool has_int_ref;
bool has_ref2;
+ bool higher_gpio_bits;
u8 num_gpios;
};

@@ -195,6 +230,24 @@ struct ad7173_state {
#endif
};

+static unsigned int ad4115_sinc5_data_rates[] = {
+ 24845000, 24845000, 20725000, 20725000, /* 0-3 */
+ 15564000, 13841000, 10390000, 10390000, /* 4-7 */
+ 4994000, 2499000, 1000000, 500000, /* 8-11 */
+ 395500, 200000, 100000, 59890, /* 12-15 */
+ 49920, 20000, 16660, 10000, /* 16-19 */
+ 5000, 2500, 2500, /* 20-22 */
+};
+
+static unsigned int ad4116_sinc5_data_rates[] = {
+ 12422360, 12422360, 12422360, 12422360, /* 0-3 */
+ 10362690, 10362690, 7782100, 6290530, /* 4-7 */
+ 5194800, 2496900, 1007600, 499900, /* 8-11 */
+ 390600, 200300, 100000, 59750, /* 12-15 */
+ 49840, 20000, 16650, 10000, /* 16-19 */
+ 5000, 2500, 1250, /* 20-22 */
+};
+
static const unsigned int ad7173_sinc5_data_rates[] = {
6211000, 6211000, 6211000, 6211000, 6211000, 6211000, 5181000, 4444000, /* 0-7 */
3115000, 2597000, 1007000, 503800, 381000, 200300, 100500, 59520, /* 8-15 */
@@ -210,14 +263,109 @@ static const unsigned int ad7175_sinc5_data_rates[] = {
5000, /* 20 */
};

+static unsigned int ad4111_current_channel_config[] = {
+ [AD4111_CURRENT_IN0P_IN0N] = 0x1E8,
+ [AD4111_CURRENT_IN1P_IN1N] = 0x1C9,
+ [AD4111_CURRENT_IN2P_IN2N] = 0x1AA,
+ [AD4111_CURRENT_IN3P_IN3N] = 0x18B,
+};
+
static const struct ad7173_device_info ad7173_device_info[] = {
+ [ID_AD4111] = {
+ .name = "ad4111",
+ .id = AD7173_AD4111_AD4112_AD4114_ID,
+ .num_voltage_inputs_with_divider = 8,
+ .num_channels = 16,
+ .num_configs = 8,
+ .num_voltage_inputs = 8,
+ .num_gpios = 2,
+ .higher_gpio_bits = true,
+ .has_temp = true,
+ .has_vcom_input = true,
+ .has_input_buf = true,
+ .has_current_inputs = true,
+ .has_int_ref = true,
+ .clock = 2 * HZ_PER_MHZ,
+ .sinc5_data_rates = ad7173_sinc5_data_rates,
+ .num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
+ },
+ [ID_AD4112] = {
+ .name = "ad4112",
+ .id = AD7173_AD4111_AD4112_AD4114_ID,
+ .num_voltage_inputs_with_divider = 8,
+ .num_channels = 16,
+ .num_configs = 8,
+ .num_voltage_inputs = 8,
+ .num_gpios = 2,
+ .higher_gpio_bits = true,
+ .has_vcom_input = true,
+ .has_temp = true,
+ .has_input_buf = true,
+ .has_current_inputs = true,
+ .has_int_ref = true,
+ .clock = 2 * HZ_PER_MHZ,
+ .sinc5_data_rates = ad7173_sinc5_data_rates,
+ .num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
+ },
+ [ID_AD4114] = {
+ .name = "ad4114",
+ .id = AD7173_AD4111_AD4112_AD4114_ID,
+ .num_voltage_inputs_with_divider = 16,
+ .num_channels = 16,
+ .num_configs = 8,
+ .num_voltage_inputs = 16,
+ .num_gpios = 4,
+ .higher_gpio_bits = true,
+ .has_vcom_input = true,
+ .has_temp = true,
+ .has_input_buf = true,
+ .has_int_ref = true,
+ .clock = 2 * HZ_PER_MHZ,
+ .sinc5_data_rates = ad7173_sinc5_data_rates,
+ .num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
+ },
+ [ID_AD4115] = {
+ .name = "ad4115",
+ .id = AD4115_ID,
+ .num_voltage_inputs_with_divider = 16,
+ .num_channels = 16,
+ .num_configs = 8,
+ .num_voltage_inputs = 16,
+ .num_gpios = 4,
+ .higher_gpio_bits = true,
+ .has_vcom_input = true,
+ .has_temp = true,
+ .has_input_buf = true,
+ .has_int_ref = true,
+ .clock = 8 * HZ_PER_MHZ,
+ .sinc5_data_rates = ad4115_sinc5_data_rates,
+ .num_sinc5_data_rates = ARRAY_SIZE(ad4115_sinc5_data_rates),
+ },
+ [ID_AD4116] = {
+ .name = "ad4116",
+ .id = AD4116_ID,
+ .num_voltage_inputs_with_divider = 11,
+ .num_channels = 16,
+ .num_configs = 8,
+ .num_voltage_inputs = 16,
+ .num_gpios = 4,
+ .higher_gpio_bits = true,
+ .has_vcom_input = true,
+ .has_temp = true,
+ .has_input_buf = true,
+ .has_int_ref = true,
+ .clock = 4 * HZ_PER_MHZ,
+ .sinc5_data_rates = ad4116_sinc5_data_rates,
+ .num_sinc5_data_rates = ARRAY_SIZE(ad4116_sinc5_data_rates),
+ },
[ID_AD7172_2] = {
.name = "ad7172-2",
.id = AD7172_2_ID,
- .num_inputs = 5,
+ .num_voltage_inputs = 5,
.num_channels = 4,
.num_configs = 4,
.num_gpios = 2,
+ .higher_gpio_bits = false,
.has_temp = true,
.has_input_buf = true,
.has_int_ref = true,
@@ -229,10 +377,11 @@ static const struct ad7173_device_info ad7173_device_info[] = {
[ID_AD7172_4] = {
.name = "ad7172-4",
.id = AD7172_4_ID,
- .num_inputs = 9,
+ .num_voltage_inputs = 9,
.num_channels = 8,
.num_configs = 8,
.num_gpios = 4,
+ .higher_gpio_bits = false,
.has_temp = false,
.has_input_buf = true,
.has_ref2 = true,
@@ -243,11 +392,12 @@ static const struct ad7173_device_info ad7173_device_info[] = {
},
[ID_AD7173_8] = {
.name = "ad7173-8",
- .id = AD7173_ID,
- .num_inputs = 17,
+ .id = AD7173_AD4111_AD4112_AD4114_ID,
+ .num_voltage_inputs = 17,
.num_channels = 16,
.num_configs = 8,
.num_gpios = 4,
+ .higher_gpio_bits = false,
.has_temp = true,
.has_input_buf = true,
.has_int_ref = true,
@@ -260,10 +410,11 @@ static const struct ad7173_device_info ad7173_device_info[] = {
[ID_AD7175_2] = {
.name = "ad7175-2",
.id = AD7175_2_ID,
- .num_inputs = 5,
+ .num_voltage_inputs = 5,
.num_channels = 4,
.num_configs = 4,
.num_gpios = 2,
+ .higher_gpio_bits = false,
.has_temp = true,
.has_input_buf = true,
.has_int_ref = true,
@@ -275,10 +426,11 @@ static const struct ad7173_device_info ad7173_device_info[] = {
[ID_AD7175_8] = {
.name = "ad7175-8",
.id = AD7175_8_ID,
- .num_inputs = 17,
+ .num_voltage_inputs = 17,
.num_channels = 16,
.num_configs = 8,
.num_gpios = 4,
+ .higher_gpio_bits = false,
.has_temp = true,
.has_input_buf = true,
.has_int_ref = true,
@@ -291,10 +443,11 @@ static const struct ad7173_device_info ad7173_device_info[] = {
[ID_AD7176_2] = {
.name = "ad7176-2",
.id = AD7176_ID,
- .num_inputs = 5,
+ .num_voltage_inputs = 5,
.num_channels = 4,
.num_configs = 4,
.num_gpios = 2,
+ .higher_gpio_bits = false,
.has_temp = false,
.has_input_buf = false,
.has_int_ref = true,
@@ -306,10 +459,11 @@ static const struct ad7173_device_info ad7173_device_info[] = {
[ID_AD7177_2] = {
.name = "ad7177-2",
.id = AD7177_ID,
- .num_inputs = 5,
+ .num_voltage_inputs = 5,
.num_channels = 4,
.num_configs = 4,
.num_gpios = 2,
+ .higher_gpio_bits = false,
.has_temp = true,
.has_input_buf = true,
.has_int_ref = true,
@@ -328,6 +482,12 @@ static const char *const ad7173_ref_sel_str[] = {
[AD7173_SETUP_REF_SEL_AVDD1_AVSS] = "avdd",
};

+static const char *const ad7173_channel_types[] = {
+ [AD7173_CHAN_SINGLE_ENDED] = "single-ended",
+ [AD7173_CHAN_PSEUDO_DIFFERENTIAL] = "pseudo-differential",
+ [AD7173_CHAN_DIFFERENTIAL] = "differential",
+};
+
static const char *const ad7173_clk_sel[] = {
"ext-clk", "xtal"
};
@@ -360,6 +520,15 @@ static int ad7173_mask_xlate(struct gpio_regmap *gpio, unsigned int base,
return 0;
}

+static int ad4111_mask_xlate(struct gpio_regmap *gpio, unsigned int base,
+ unsigned int offset, unsigned int *reg,
+ unsigned int *mask)
+{
+ *mask = AD4111_GPO01_DATA(offset);
+ *reg = base;
+ return 0;
+}
+
static void ad7173_gpio_disable(void *data)
{
struct ad7173_state *st = data;
@@ -392,7 +561,10 @@ static int ad7173_gpio_init(struct ad7173_state *st)
gpio_regmap.regmap = st->reg_gpiocon_regmap;
gpio_regmap.ngpio = st->info->num_gpios;
gpio_regmap.reg_set_base = AD7173_REG_GPIO;
- gpio_regmap.reg_mask_xlate = ad7173_mask_xlate;
+ if (st->info->higher_gpio_bits)
+ gpio_regmap.reg_mask_xlate = ad4111_mask_xlate;
+ else
+ gpio_regmap.reg_mask_xlate = ad7173_mask_xlate;

st->gpio_regmap = devm_gpio_regmap_register(dev, &gpio_regmap);
ret = PTR_ERR_OR_ZERO(st->gpio_regmap);
@@ -687,18 +859,33 @@ static int ad7173_read_raw(struct iio_dev *indio_dev,

return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
- if (chan->type == IIO_TEMP) {
+
+ switch (chan->type) {
+ case IIO_TEMP:
temp = AD7173_VOLTAGE_INT_REF_uV * MILLI;
temp /= AD7173_TEMP_SENSIIVITY_uV_per_C;
*val = temp;
*val2 = chan->scan_type.realbits;
- } else {
+ return IIO_VAL_FRACTIONAL_LOG2;
+ case IIO_VOLTAGE:
*val = ad7173_get_ref_voltage_milli(st, ch->cfg.ref_sel);
*val2 = chan->scan_type.realbits - !!(ch->cfg.bipolar);
+
+ if (chan->channel < st->info->num_voltage_inputs_with_divider)
+ *val *= AD4111_DIVIDER_RATIO;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ case IIO_CURRENT:
+ *val = ad7173_get_ref_voltage_milli(st, ch->cfg.ref_sel);
+ *val /= AD4111_SHUNT_RESISTOR_OHM;
+ *val2 = chan->scan_type.realbits - (ch->cfg.bipolar ? 1 : 0);
+ return IIO_VAL_FRACTIONAL_LOG2;
+ default:
+ return -EINVAL;
}
- return IIO_VAL_FRACTIONAL_LOG2;
case IIO_CHAN_INFO_OFFSET:
- if (chan->type == IIO_TEMP) {
+
+ switch (chan->type) {
+ case IIO_TEMP:
/* 0 Kelvin -> raw sample */
temp = -ABSOLUTE_ZERO_MILLICELSIUS;
temp *= AD7173_TEMP_SENSIIVITY_uV_per_C;
@@ -707,10 +894,14 @@ static int ad7173_read_raw(struct iio_dev *indio_dev,
AD7173_VOLTAGE_INT_REF_uV *
MILLI);
*val = -temp;
- } else {
+ return IIO_VAL_INT;
+ case IIO_VOLTAGE:
+ case IIO_CURRENT:
*val = -BIT(chan->scan_type.realbits - 1);
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
}
- return IIO_VAL_INT;
case IIO_CHAN_INFO_SAMP_FREQ:
reg = st->channels[chan->address].cfg.odr;

@@ -926,13 +1117,37 @@ static int ad7173_register_clk_provider(struct iio_dev *indio_dev)
&st->int_clk_hw);
}

+static int ad4111_validate_current_ain(struct ad7173_state *st,
+ unsigned int ain[2])
+{
+ struct device *dev = &st->sd.spi->dev;
+ int i;
+
+ if (!st->info->has_current_inputs)
+ return dev_err_probe(dev, -EINVAL,
+ "Model %s does not support current channels\n",
+ st->info->name);
+
+ for (i = 0; i < ARRAY_SIZE(ad4111_current_channel_config); i++)
+ if (ad4111_current_channel_config[i] == AD7173_CH_ADDRESS(ain[0], ain[1]))
+ return 0;
+
+ return dev_err_probe(dev, -EINVAL,
+ "Current channel configuration invalid (%d, %d).\n",
+ ain[0], ain[1]);
+}
+
static int ad7173_validate_voltage_ain_inputs(struct ad7173_state *st,
unsigned int ain[2])
{
struct device *dev = &st->sd.spi->dev;
+ bool ain_selects_normal_input[] = {
+ ain[0] < st->info->num_voltage_inputs,
+ ain[1] < st->info->num_voltage_inputs
+ };

for (int i = 0; i < 2; i++) {
- if (ain[i] < st->info->num_inputs)
+ if (ain_selects_normal_input[i])
continue;

if (ain[i] == AD7173_AIN_REF_POS || ain[i] == AD7173_AIN_REF_NEG)
@@ -943,11 +1158,27 @@ static int ad7173_validate_voltage_ain_inputs(struct ad7173_state *st,
st->info->has_common_input)
continue;

+ if (st->info->has_vcom_input && ain[i] == AD411X_VCOM_INPUT) {
+ if (ain_selects_normal_input[(i + 1) % 2] &&
+ ain[(i + 1) % 2] >= st->info->num_voltage_inputs_with_divider)
+ return dev_err_probe(dev, -EINVAL,
+ "VCOM must be paired with inputs having divider.\n");
+
+ continue;
+ }
+
return dev_err_probe(dev, -EINVAL,
"Input pin number out of range for pair (%d %d).\n",
ain[0], ain[1]);
}

+ if ((ain_selects_normal_input[0] && ain_selects_normal_input[1]) &&
+ ((ain[0] >= st->info->num_voltage_inputs_with_divider) !=
+ (ain[1] >= st->info->num_voltage_inputs_with_divider)))
+ return dev_err_probe(dev, -EINVAL,
+ "Both inputs must either have a voltage divider or not have: (%d %d).\n",
+ ain[0], ain[1]);
+
return 0;
}

@@ -979,7 +1210,7 @@ static int ad7173_fw_parse_channel_config(struct iio_dev *indio_dev)
struct device *dev = indio_dev->dev.parent;
struct iio_chan_spec *chan_arr, *chan;
unsigned int ain[2], chan_index = 0;
- int ref_sel, ret, num_channels;
+ int ref_sel, ret, is_current_chan, num_channels;

num_channels = device_get_child_node_count(dev);

@@ -1032,9 +1263,16 @@ static int ad7173_fw_parse_channel_config(struct iio_dev *indio_dev)
if (ret)
return ret;

- ret = ad7173_validate_voltage_ain_inputs(st, ain);
- if (ret)
- return ret;
+ is_current_chan = fwnode_property_read_bool(child, "adi,current-channel");
+ if (is_current_chan) {
+ ret = ad4111_validate_current_ain(st, ain);
+ if (ret)
+ return ret;
+ } else {
+ ret = ad7173_validate_voltage_ain_inputs(st, ain);
+ if (ret)
+ return ret;
+ }

ret = fwnode_property_match_property_string(child,
"adi,reference-select",
@@ -1058,17 +1296,26 @@ static int ad7173_fw_parse_channel_config(struct iio_dev *indio_dev)
chan->scan_index = chan_index;
chan->channel = ain[0];
chan->channel2 = ain[1];
- chan->differential = true;
-
chan_st_priv->ain = AD7173_CH_ADDRESS(ain[0], ain[1]);
chan_st_priv->chan_reg = chan_index;
- chan_st_priv->cfg.input_buf = st->info->has_input_buf;
chan_st_priv->cfg.odr = 0;
-
chan_st_priv->cfg.bipolar = fwnode_property_read_bool(child, "bipolar");
+
if (chan_st_priv->cfg.bipolar)
chan->info_mask_separate |= BIT(IIO_CHAN_INFO_OFFSET);

+ if (is_current_chan)
+ chan->type = IIO_CURRENT;
+ else
+ chan_st_priv->cfg.input_buf = st->info->has_input_buf;
+
+ ret = fwnode_property_match_property_string(child,
+ "adi,channel-type",
+ ad7173_channel_types,
+ ARRAY_SIZE(ad7173_channel_types));
+ chan->differential = (ret < 0 || ret == AD7173_CHAN_DIFFERENTIAL)
+ ? true : false;
+
chan_index++;
}
return 0;
@@ -1195,6 +1442,14 @@ static int ad7173_probe(struct spi_device *spi)
}

static const struct of_device_id ad7173_of_match[] = {
+ { .compatible = "ad4111",
+ .data = &ad7173_device_info[ID_AD4111]},
+ { .compatible = "ad4112",
+ .data = &ad7173_device_info[ID_AD4112]},
+ { .compatible = "ad4114",
+ .data = &ad7173_device_info[ID_AD4114]},
+ { .compatible = "ad4115",
+ .data = &ad7173_device_info[ID_AD4115]},
{ .compatible = "adi,ad7172-2",
.data = &ad7173_device_info[ID_AD7172_2]},
{ .compatible = "adi,ad7172-4",
@@ -1214,6 +1469,11 @@ static const struct of_device_id ad7173_of_match[] = {
MODULE_DEVICE_TABLE(of, ad7173_of_match);

static const struct spi_device_id ad7173_id_table[] = {
+ { "ad4111", (kernel_ulong_t)&ad7173_device_info[ID_AD4111]},
+ { "ad4112", (kernel_ulong_t)&ad7173_device_info[ID_AD4112]},
+ { "ad4114", (kernel_ulong_t)&ad7173_device_info[ID_AD4114]},
+ { "ad4115", (kernel_ulong_t)&ad7173_device_info[ID_AD4115]},
+ { "ad4116", (kernel_ulong_t)&ad7173_device_info[ID_AD4116]},
{ "ad7172-2", (kernel_ulong_t)&ad7173_device_info[ID_AD7172_2]},
{ "ad7172-4", (kernel_ulong_t)&ad7173_device_info[ID_AD7172_4]},
{ "ad7173-8", (kernel_ulong_t)&ad7173_device_info[ID_AD7173_8]},
@@ -1238,5 +1498,5 @@ module_spi_driver(ad7173_driver);
MODULE_IMPORT_NS(IIO_AD_SIGMA_DELTA);
MODULE_AUTHOR("Lars-Peter Clausen <[email protected]>");
MODULE_AUTHOR("Dumitru Ceclan <[email protected]>");
-MODULE_DESCRIPTION("Analog Devices AD7172/AD7173/AD7175/AD7176 ADC driver");
+MODULE_DESCRIPTION("Analog Devices AD717x and AD411x ADC driver");
MODULE_LICENSE("GPL");

--
2.43.0

2024-05-14 07:26:14

[permalink] [raw]

Subject: [PATCH v2 7/9] iio: adc: ad7173: Remove index from temp channel

From: Dumitru Ceclan <[email protected]>

Temperature channel is unique per device, index is not needed.

This is breaking userspace: as main driver has not reached mainline yet
it won't affect users as there are none.

Signed-off-by: Dumitru Ceclan <[email protected]>
---
drivers/iio/adc/ad7173.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
index d965b66d4d5a..d66b47e1a186 100644
--- a/drivers/iio/adc/ad7173.c
+++ b/drivers/iio/adc/ad7173.c
@@ -828,7 +828,6 @@ static const struct iio_chan_spec ad7173_channel_template = {

static const struct iio_chan_spec ad7173_temp_iio_channel_template = {
.type = IIO_TEMP,
- .indexed = 1,
.channel = AD7173_AIN_TEMP_POS,
.channel2 = AD7173_AIN_TEMP_NEG,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |

--
2.43.0

2024-05-15 22:35:49

[permalink] [raw]

Subject: Re: [PATCH v2 0/9] Add support for AD411x

On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay
<[email protected]> wrote:
>
> This patch series adds support for the Analog Devices AD4111, AD4112,
> AD4114, AD4115, AD4116 within the existing AD7173 driver.
>

It looks like most of the patches in this series are cleanups and
fixes of the existing driver unrelated to adding AD411x. Perhaps it
would be better to split those out into a separate series so we can
focus on that first? Especially since several of them need to be sent
as fixes for the v6.10 kernel to avoid breaking usespace or bindings
in the next release.

2024-05-15 22:38:07

[permalink] [raw]

Subject: Re: [PATCH v2 1/9] dt-bindings: adc: ad7173: add support for ad411x

On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay
<[email protected]> wrote:
>
> From: Dumitru Ceclan <[email protected]>
>
> Add support for: AD4111, AD4112, AD4114, AD4115, AD4116.
>
> AD411x family ADCs support a VCOM pin, dedicated for single-ended usage.
> AD4111/AD4112 support current channels, usage is implemented by
> specifying channel reg values bigger than 15.
>
> Signed-off-by: Dumitru Ceclan <[email protected]>
> ---
> .../devicetree/bindings/iio/adc/adi,ad7173.yaml | 118 ++++++++++++++++++++-
> 1 file changed, 117 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
> index ea6cfcd0aff4..6cc3514f5ed8 100644
> --- a/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
> +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
> @@ -19,7 +19,18 @@ description: |
> primarily for measurement of signals close to DC but also delivers
> outstanding performance with input bandwidths out to ~10kHz.
>
> + Analog Devices AD411x ADC's:
> + The AD411X family encompasses a series of low power, low noise, 24-bit,
> + sigma-delta analog-to-digital converters that offer a versatile range of
> + specifications. They integrate an analog front end suitable for processing
> + fully differential/single-ended and bipolar voltage inputs.
> +
> Datasheets for supported chips:
> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4111.pdf
> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4112.pdf
> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4114.pdf
> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4115.pdf
> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4116.pdf
> https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-2.pdf
> https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-4.pdf
> https://www.analog.com/media/en/technical-documentation/data-sheets/AD7173-8.pdf
> @@ -31,6 +42,11 @@ description: |
> properties:
> compatible:
> enum:
> + - adi,ad4111
> + - adi,ad4112
> + - adi,ad4114
> + - adi,ad4115
> + - adi,ad4116
> - adi,ad7172-2
> - adi,ad7172-4
> - adi,ad7173-8
> @@ -129,6 +145,31 @@ patternProperties:
> maximum: 15
>
> diff-channels:
> + description: |
> + For using current channels specify select the current inputs
> + and enable the adi,current-channel property.
> +
> + Family AD411x supports a dedicated VCOM voltage input.

Did you mean VINCOM? Searching the datasheets for "VCOM" comes up empty.

> + To select it set the second channel to 16.
> + (VIN2, VCOM) -> diff-channels = <2 16>

Jonathan mentioned this in v1 with regard to the current inputs, but
it applies here too. There is a new proposed single-channel property
[1] that would be preferred when an input is used as a single-ended or
pseudo-differential input (i.e. with VINCOM or ADCIN15).

[1]: https://lore.kernel.org/linux-iio/[email protected]/

> +
> + There are special values that can be selected besides the voltage
> + analog inputs:
> + 21: REF+
> + 22: REF−
> + Supported only by AD7172-2, AD7172-4, AD7175-2, AD7175-8, AD7177-2:
> + 19: ((AVDD1 − AVSS)/5)+
> + 20: ((AVDD1 − AVSS)/5)−
> + Supported only by AD4111, AD4112:
> + 12: IIN3+
> + 11: IIN3−
> + 13: IIN2+
> + 10: IIN2−
> + 14: IIN1+
> + 9: IIN1−
> + 15: IIN0+
> + 8: IIN0−

I just made a late reply on v1 where Jonathan suggested that the
current inputs are differential with a similar comment to this:

It doesn't seem to me like current inputs are differential if they are
only measuring one current. They take 2 pins because you need a way
for current to come in and go back out, but the datasheet calls them
single-ended inputs.

> +
> items:
> minimum: 0
> maximum: 31
> @@ -154,6 +195,23 @@ patternProperties:
> - avdd
> default: refout-avss
>
> + adi,current-channel:
> + description: |
> + Signal that the selected inputs are current channels.
> + Only available on AD4111 and AD4112.
> + type: boolean
> +
> + adi,channel-type:
> + description:
> + Used to differentiate between different channel types as the device
> + register configurations are the same for all usage types.
> + $ref: /schemas/types.yaml#/definitions/string
> + enum:
> + - single-ended
> + - pseudo-differential
> + - differential
> + default: differential
> +

As suggested above, we should soon have diff-channels and
single-channel to differentiate between (fully) differential and
single-ended. Do we actually need to differentiate between
single-ended and pseudo-differential though?

I think the AD4116 datasheet is the only one that uses both of those
terms. It gives the examples that for "single-ended" ADCIN15 would be
connected to AVSS and for "pseudo-differential" ADCIN15 would be
connected to REFOUT (AVSS + 2.5 V). So the only difference seems to be
if the voltage on ADCIN15 is == 0V or != 0V.

To make this like other pseudo-differential chips we have done
recently, it seems to me like we should have an adcin15-supply
property to describe the ADCIN15 input. Then we could use that
property to determine single-ended vs. pseudo-differential (if there
actually is a need for that) and we wouldn't need the adi,channel-type
property.

> required:
> - reg
> - diff-channels
> @@ -166,7 +224,6 @@ allOf:
> - $ref: /schemas/spi/spi-peripheral-props.yaml#
>
> # Only ad7172-4, ad7173-8 and ad7175-8 support vref2
> - # Other models have [0-3] channel registers
> - if:
> properties:
> compatible:
> @@ -187,6 +244,37 @@ allOf:
> - vref
> - refout-avss
> - avdd
> +
> + - if:
> + properties:
> + compatible:
> + contains:
> + enum:
> + - adi,ad4114
> + - adi,ad4115
> + - adi,ad4116
> + - adi,ad7173-8
> + - adi,ad7175-8
> + then:
> + patternProperties:
> + "^channel@[0-9a-f]$":
> + properties:
> + reg:
> + maximum: 15

As discussed recently in the the very similar ad719x bindings [2], we
may have been misunderstanding this limit so far. 15 is a bit
artificially low since input pins can be used more than once in
different "channels". But that is really an issues with the existing
bindings, not just this patch.

[2]: https://lore.kernel.org/linux-iio/20240511122955.2372f56e@jic23-huawei/

> +
> + - if:
> + properties:
> + compatible:
> + contains:
> + enum:
> + - adi,ad7172-2
> + - adi,ad7175-2
> + - adi,ad7176-2
> + - adi,ad7177-2
> + then:
> + patternProperties:
> + "^channel@[0-9a-f]$":
> + properties:
> reg:
> maximum: 3
>
> @@ -210,6 +298,34 @@ allOf:
> required:
> - adi,reference-select
>
> + - if:
> + properties:
> + compatible:
> + contains:
> + enum:
> + - adi,ad4111
> + - adi,ad4112
> + - adi,ad4114
> + - adi,ad4115
> + - adi,ad4116
> + then:
> + properties:
> + avdd2-supply: false
> +
> + - if:
> + properties:
> + compatible:
> + not:
> + contains:
> + enum:
> + - adi,ad4111
> + - adi,ad4112
> + then:
> + patternProperties:
> + "^channel@[0-9a-f]$":
> + properties:
> + adi,current-channel: false
> +
> - if:
> anyOf:
> - required: [clock-names]
>
> --
> 2.43.0
>
>

2024-05-15 22:55:02

[permalink] [raw]

Subject: Re: [PATCH v2 4/9] iio: adc: ad7173: refactor ain and vref selection

On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay
<[email protected]> wrote:
>
> From: Dumitru Ceclan <[email protected]>
>
> Move validation of analog inputs and reference voltage selection to
> separate functions to reduce the size of the channel config parsing
> function and improve readability.
>
> Signed-off-by: Dumitru Ceclan <[email protected]>
> ---

Reviewed-by: David Lechner <[email protected]>

2024-05-15 23:27:57

[permalink] [raw]

Subject: Re: [PATCH v2 5/9] iio: adc: ad7173: add support for special inputs

On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay
<[email protected]> wrote:
>
> From: Dumitru Ceclan <[email protected]>
>
> Add support for selecting REF+ and REF- inputs on all models.
> Add support for selecting ((AVDD1 − AVSS)/5) inputs
> on supported models.
>
> Signed-off-by: Dumitru Ceclan <[email protected]>
> ---
> drivers/iio/adc/ad7173.c | 21 +++++++++++++++++++++
> 1 file changed, 21 insertions(+)
>
> diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
> index fb33534d63a9..1e9ba3070770 100644
> --- a/drivers/iio/adc/ad7173.c
> +++ b/drivers/iio/adc/ad7173.c
> @@ -65,6 +65,10 @@
> FIELD_PREP(AD7173_CH_SETUP_AINNEG_MASK, neg))
> #define AD7173_AIN_TEMP_POS 17
> #define AD7173_AIN_TEMP_NEG 18
> +#define AD7173_AIN_COM_IN_POS 19
> +#define AD7173_AIN_COM_IN_NEG 20
> +#define AD7173_AIN_REF_POS 21
> +#define AD7173_AIN_REF_NEG 22
>
> #define AD7172_2_ID 0x00d0
> #define AD7175_ID 0x0cd0
> @@ -145,6 +149,8 @@ struct ad7173_device_info {
> unsigned int id;
> char *name;
> bool has_temp;
> + /* ((AVDD1 − AVSS)/5) */
> + bool has_common_input;
> bool has_input_buf;
> bool has_int_ref;
> bool has_ref2;
> @@ -215,6 +221,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
> .has_temp = true,
> .has_input_buf = true,
> .has_int_ref = true,
> + .has_common_input = true,
> .clock = 2 * HZ_PER_MHZ,
> .sinc5_data_rates = ad7173_sinc5_data_rates,
> .num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
> @@ -228,6 +235,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
> .has_temp = false,
> .has_input_buf = true,
> .has_ref2 = true,
> + .has_common_input = true,
> .clock = 2 * HZ_PER_MHZ,
> .sinc5_data_rates = ad7173_sinc5_data_rates,
> .num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
> @@ -243,6 +251,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
> .has_input_buf = true,
> .has_int_ref = true,
> .has_ref2 = true,
> + .has_common_input = false,
> .clock = 2 * HZ_PER_MHZ,
> .sinc5_data_rates = ad7173_sinc5_data_rates,
> .num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
> @@ -257,6 +266,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
> .has_temp = true,
> .has_input_buf = true,
> .has_int_ref = true,
> + .has_common_input = true,
> .clock = 16 * HZ_PER_MHZ,
> .sinc5_data_rates = ad7175_sinc5_data_rates,
> .num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
> @@ -271,6 +281,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
> .has_input_buf = true,
> .has_int_ref = true,
> .has_ref2 = true,
> + .has_common_input = true,
> .clock = 16 * HZ_PER_MHZ,
> .sinc5_data_rates = ad7175_sinc5_data_rates,
> .num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
> @@ -285,6 +296,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
> .has_temp = false,
> .has_input_buf = false,
> .has_int_ref = true,
> + .has_common_input = false,
> .clock = 16 * HZ_PER_MHZ,
> .sinc5_data_rates = ad7175_sinc5_data_rates,
> .num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
> @@ -298,6 +310,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
> .has_temp = true,
> .has_input_buf = true,
> .has_int_ref = true,
> + .has_common_input = true,
> .clock = 16 * HZ_PER_MHZ,
> .odr_start_value = AD7177_ODR_START_VALUE,
> .sinc5_data_rates = ad7175_sinc5_data_rates,
> @@ -920,6 +933,14 @@ static int ad7173_validate_voltage_ain_inputs(struct ad7173_state *st,
> if (ain[i] < st->info->num_inputs)
> continue;
>
> + if (ain[i] == AD7173_AIN_REF_POS || ain[i] == AD7173_AIN_REF_NEG)
> + continue;
> +
> + if ((ain[i] == AD7173_AIN_COM_IN_POS ||
> + ain[i] == AD7173_AIN_COM_IN_NEG) &&
> + st->info->has_common_input)
> + continue;
> +

If there is only one valid combination, it seems like these should be
fixed channels like the temperature input rather than something coming
from the device tree.

It looks like on AD411x, it is the case that there is only one valid
option for the reference input in the channel configuration. But in
the case of AD717x since both REF+ and REF- are listed as possible
inputs for both AINPOS0 and AINNEG0, it seems like they could be mixed
and matched with other channels. The datasheet doesn't seem very clear
on this though.

If it is valid to combine, say AIN0 with REF+ though, then the
validation would need to be relaxed. But I'm guessing that is not
actually the case?

> return dev_err_probe(dev, -EINVAL,
> "Input pin number out of range for pair (%d %d).\n",
> ain[0], ain[1]);
>
> --
> 2.43.0
>
>

2024-05-15 23:32:46

[permalink] [raw]

Subject: Re: [PATCH v2 6/9] iio: adc: ad7173: Add ad7173_device_info names

On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay
<[email protected]> wrote:
>
> From: Dumitru Ceclan <[email protected]>
>
> Add missing names from the device info struct for 3 models to ensure
> consistency with the rest of the models.
>

This affects userspace, right? So probably needs a Fixes: to make sure
this gets into the 6.10 release?

> Signed-off-by: Dumitru Ceclan <[email protected]>
> ---
> drivers/iio/adc/ad7173.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
> index 1e9ba3070770..d965b66d4d5a 100644
> --- a/drivers/iio/adc/ad7173.c
> +++ b/drivers/iio/adc/ad7173.c
> @@ -227,6 +227,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
> .num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
> },
> [ID_AD7172_4] = {
> + .name = "ad7172-4",
> .id = AD7172_4_ID,
> .num_inputs = 9,
> .num_channels = 8,
> @@ -272,6 +273,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
> .num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
> },
> [ID_AD7175_8] = {
> + .name = "ad7175-8",
> .id = AD7175_8_ID,
> .num_inputs = 17,
> .num_channels = 16,
> @@ -302,6 +304,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
> .num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
> },
> [ID_AD7177_2] = {
> + .name = "ad7177-2",
> .id = AD7177_ID,
> .num_inputs = 5,
> .num_channels = 4,
>
> --
> 2.43.0
>
>

2024-05-15 23:34:40

[permalink] [raw]

Subject: Re: [PATCH v2 7/9] iio: adc: ad7173: Remove index from temp channel

On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay
<[email protected]> wrote:
>
> From: Dumitru Ceclan <[email protected]>
>
> Temperature channel is unique per device, index is not needed.
>
> This is breaking userspace: as main driver has not reached mainline yet
> it won't affect users as there are none.

But it is queued up, so probably need a Fixes: here to make sure it
makes it into the release.

>
> Signed-off-by: Dumitru Ceclan <[email protected]>
> ---
> drivers/iio/adc/ad7173.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
> index d965b66d4d5a..d66b47e1a186 100644
> --- a/drivers/iio/adc/ad7173.c
> +++ b/drivers/iio/adc/ad7173.c
> @@ -828,7 +828,6 @@ static const struct iio_chan_spec ad7173_channel_template = {
>
> static const struct iio_chan_spec ad7173_temp_iio_channel_template = {
> .type = IIO_TEMP,
> - .indexed = 1,
> .channel = AD7173_AIN_TEMP_POS,
> .channel2 = AD7173_AIN_TEMP_NEG,
> .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>
> --
> 2.43.0
>
>

2024-05-16 15:49:52

[permalink] [raw]

Subject: Re: [PATCH v2 1/9] dt-bindings: adc: ad7173: add support for ad411x

On 16/05/2024 01:37, David Lechner wrote:
> On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay
> <[email protected]> wrote:
>>
>> From: Dumitru Ceclan <[email protected]>
>>
>> Add support for: AD4111, AD4112, AD4114, AD4115, AD4116.
>>
>> AD411x family ADCs support a VCOM pin, dedicated for single-ended usage.
>> AD4111/AD4112 support current channels, usage is implemented by
>> specifying channel reg values bigger than 15.
>>
>> Signed-off-by: Dumitru Ceclan <[email protected]>
>> ---
>> .../devicetree/bindings/iio/adc/adi,ad7173.yaml | 118 ++++++++++++++++++++-
>> 1 file changed, 117 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
>> index ea6cfcd0aff4..6cc3514f5ed8 100644
>> --- a/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
>> +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
>> @@ -19,7 +19,18 @@ description: |
>> primarily for measurement of signals close to DC but also delivers
>> outstanding performance with input bandwidths out to ~10kHz.
>>
>> + Analog Devices AD411x ADC's:
>> + The AD411X family encompasses a series of low power, low noise, 24-bit,
>> + sigma-delta analog-to-digital converters that offer a versatile range of
>> + specifications. They integrate an analog front end suitable for processing
>> + fully differential/single-ended and bipolar voltage inputs.
>> +
>> Datasheets for supported chips:
>> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4111.pdf
>> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4112.pdf
>> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4114.pdf
>> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4115.pdf
>> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4116.pdf
>> https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-2.pdf
>> https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-4.pdf
>> https://www.analog.com/media/en/technical-documentation/data-sheets/AD7173-8.pdf
>> @@ -31,6 +42,11 @@ description: |
>> properties:
>> compatible:
>> enum:
>> + - adi,ad4111
>> + - adi,ad4112
>> + - adi,ad4114
>> + - adi,ad4115
>> + - adi,ad4116
>> - adi,ad7172-2
>> - adi,ad7172-4
>> - adi,ad7173-8
>> @@ -129,6 +145,31 @@ patternProperties:
>> maximum: 15
>>
>> diff-channels:
>> + description: |
>> + For using current channels specify select the current inputs
>> + and enable the adi,current-channel property.
>> +
>> + Family AD411x supports a dedicated VCOM voltage input.
>
> Did you mean VINCOM? Searching the datasheets for "VCOM" comes up empty.
>
Yep
>> + To select it set the second channel to 16.
>> + (VIN2, VCOM) -> diff-channels = <2 16>
>
> Jonathan mentioned this in v1 with regard to the current inputs, but
> it applies here too. There is a new proposed single-channel property
> [1] that would be preferred when an input is used as a single-ended or
> pseudo-differential input (i.e. with VINCOM or ADCIN15).
>
> [1]: https://lore.kernel.org/linux-iio/[email protected]/
>
Yet here I thought that it was clear from previous conversations that
we are not really dealing with a single-ended/pseudo-differential input,
just a differential ADC that can be used in that manner.

We do not have here such a clear cut case as with AD7194, where an input
is dedicated for single-ended/pseudo usage. Here, the inputs are mix and
match and single-ended/pseudo is obtainable with other pins than VINCOM/
ADCIN15.

When configuring channels we are *always* specifying two voltage inputs.
I strongly disagree using single-channel for voltage channels in these
families of ADC's.

>> +
>> + There are special values that can be selected besides the voltage
>> + analog inputs:
>> + 21: REF+
>> + 22: REF−
>> + Supported only by AD7172-2, AD7172-4, AD7175-2, AD7175-8, AD7177-2:
>> + 19: ((AVDD1 − AVSS)/5)+
>> + 20: ((AVDD1 − AVSS)/5)−
>> + Supported only by AD4111, AD4112:
>> + 12: IIN3+
>> + 11: IIN3−
>> + 13: IIN2+
>> + 10: IIN2−
>> + 14: IIN1+
>> + 9: IIN1−
>> + 15: IIN0+
>> + 8: IIN0−
>
> I just made a late reply on v1 where Jonathan suggested that the
> current inputs are differential with a similar comment to this:
>
> It doesn't seem to me like current inputs are differential if they are
> only measuring one current. They take 2 pins because you need a way
> for current to come in and go back out, but the datasheet calls them
> single-ended inputs.
>
It seemed to me that the conclusion that we arrived to was to expose the
precise pins that are used in the conversion and document the selection.

Yes, it is a single-ended channel. So revert to the way it was in V1 using
single-channel?

>> +
>> items:
>> minimum: 0
>> maximum: 31
>> @@ -154,6 +195,23 @@ patternProperties:
>> - avdd
>> default: refout-avss
>>
>> + adi,current-channel:
>> + description: |
>> + Signal that the selected inputs are current channels.
>> + Only available on AD4111 and AD4112.
>> + type: boolean
>> +
>> + adi,channel-type:
>> + description:
>> + Used to differentiate between different channel types as the device
>> + register configurations are the same for all usage types.
>> + $ref: /schemas/types.yaml#/definitions/string
>> + enum:
>> + - single-ended
>> + - pseudo-differential
>> + - differential
>> + default: differential
>> +
>
> As suggested above, we should soon have diff-channels and
> single-channel to differentiate between (fully) differential and
> single-ended. Do we actually need to differentiate between
> single-ended and pseudo-differential though?
>
Not really, so just a bool differential flag? (this seems weird as we have diff-channels)

> I think the AD4116 datasheet is the only one that uses both of those
> terms. It gives the examples that for "single-ended" ADCIN15 would be
> connected to AVSS and for "pseudo-differential" ADCIN15 would be
> connected to REFOUT (AVSS + 2.5 V). So the only difference seems to be
> if the voltage on ADCIN15 is == 0V or != 0V.
>
In the ad411x yes, over to ad717x it's mixed:
https://lore.kernel.org/all/[email protected]/

> To make this like other pseudo-differential chips we have done
> recently, it seems to me like we should have an adcin15-supply
> property to describe the ADCIN15 input. Then we could use that
> property to determine single-ended vs. pseudo-differential (if there
> actually is a need for that) and we wouldn't need the adi,channel-type
> property.
>

I agree that we do not need to differentiate between those two.
But the approach with the supply is too specific, the adi,channel-type
property is not only for AD4116-ADCIN15, but for all models compatible.

>> required:
>> - reg
>> - diff-channels
>> @@ -166,7 +224,6 @@ allOf:
>> - $ref: /schemas/spi/spi-peripheral-props.yaml#
>>
>> # Only ad7172-4, ad7173-8 and ad7175-8 support vref2
>> - # Other models have [0-3] channel registers
>> - if:
>> properties:
>> compatible:
>> @@ -187,6 +244,37 @@ allOf:
>> - vref
>> - refout-avss
>> - avdd
>> +
>> + - if:
>> + properties:
>> + compatible:
>> + contains:
>> + enum:
>> + - adi,ad4114
>> + - adi,ad4115
>> + - adi,ad4116
>> + - adi,ad7173-8
>> + - adi,ad7175-8
>> + then:
>> + patternProperties:
>> + "^channel@[0-9a-f]$":
>> + properties:
>> + reg:
>> + maximum: 15
>
> As discussed recently in the the very similar ad719x bindings [2], we
> may have been misunderstanding this limit so far. 15 is a bit
> artificially low since input pins can be used more than once in
> different "channels". But that is really an issues with the existing
> bindings, not just this patch.
>
> [2]: https://lore.kernel.org/linux-iio/20240511122955.2372f56e@jic23-huawei/
>
>
In this case there is a 1-1 correspondence between this reg limit and the number
of channel configuration registers available to the device. Maybe another property
then reg? Sure...but this limitation fits the current situation.

In addition, the device does not work the same as ad719x. If I understood correctly
that documentation, the configuration register needs to be rewritten for every different
input combination. This means that the driver is implemented to overwrite the reg for
every read. This device, it seems to me, is more in the liking's of write all the channel
configs at once, then keep using those.

For AD719x yes, it is artificial. Over here we have a clear reason.

>> +
>> + - if:
>> + properties:
>> + compatible:
>> + contains:
>> + enum:
>> + - adi,ad7172-2
>> + - adi,ad7175-2
>> + - adi,ad7176-2
>> + - adi,ad7177-2
>> + then:
>> + patternProperties:
>> + "^channel@[0-9a-f]$":
>> + properties:
>> reg:
>> maximum: 3
>>
>> @@ -210,6 +298,34 @@ allOf:
>> required:
>> - adi,reference-select
>>
>> + - if:
>> + properties:
>> + compatible:
>> + contains:
>> + enum:
>> + - adi,ad4111
>> + - adi,ad4112
>> + - adi,ad4114
>> + - adi,ad4115
>> + - adi,ad4116
>> + then:
>> + properties:
>> + avdd2-supply: false
>> +
>> + - if:
>> + properties:
>> + compatible:
>> + not:
>> + contains:
>> + enum:
>> + - adi,ad4111
>> + - adi,ad4112
>> + then:
>> + patternProperties:
>> + "^channel@[0-9a-f]$":
>> + properties:
>> + adi,current-channel: false
>> +
>> - if:
>> anyOf:
>> - required: [clock-names]
>>
>> --
>> 2.43.0
>>
>>

2024-05-16 16:03:34

[permalink] [raw]

Subject: Re: [PATCH v2 5/9] iio: adc: ad7173: add support for special inputs

On 16/05/2024 02:27, David Lechner wrote:
> On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay
> <[email protected]> wrote:
>>
>> From: Dumitru Ceclan <[email protected]>
>>
>> Add support for selecting REF+ and REF- inputs on all models.
>> Add support for selecting ((AVDD1 − AVSS)/5) inputs
>> on supported models.
>>
>> Signed-off-by: Dumitru Ceclan <[email protected]>
>> ---
>> drivers/iio/adc/ad7173.c | 21 +++++++++++++++++++++
>> 1 file changed, 21 insertions(+)
>>
>> diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
>> index fb33534d63a9..1e9ba3070770 100644
>> --- a/drivers/iio/adc/ad7173.c
>> +++ b/drivers/iio/adc/ad7173.c
>> @@ -65,6 +65,10 @@
>> FIELD_PREP(AD7173_CH_SETUP_AINNEG_MASK, neg))
>> #define AD7173_AIN_TEMP_POS 17
>> #define AD7173_AIN_TEMP_NEG 18
>> +#define AD7173_AIN_COM_IN_POS 19
>> +#define AD7173_AIN_COM_IN_NEG 20
>> +#define AD7173_AIN_REF_POS 21
>> +#define AD7173_AIN_REF_NEG 22
>>
>> #define AD7172_2_ID 0x00d0
>> #define AD7175_ID 0x0cd0
>> @@ -145,6 +149,8 @@ struct ad7173_device_info {
>> unsigned int id;
>> char *name;
>> bool has_temp;
>> + /* ((AVDD1 − AVSS)/5) */
>> + bool has_common_input;
>> bool has_input_buf;
>> bool has_int_ref;
>> bool has_ref2;
>> @@ -215,6 +221,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
>> .has_temp = true,
>> .has_input_buf = true,
>> .has_int_ref = true,
>> + .has_common_input = true,
>> .clock = 2 * HZ_PER_MHZ,
>> .sinc5_data_rates = ad7173_sinc5_data_rates,
>> .num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
>> @@ -228,6 +235,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
>> .has_temp = false,
>> .has_input_buf = true,
>> .has_ref2 = true,
>> + .has_common_input = true,
>> .clock = 2 * HZ_PER_MHZ,
>> .sinc5_data_rates = ad7173_sinc5_data_rates,
>> .num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
>> @@ -243,6 +251,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
>> .has_input_buf = true,
>> .has_int_ref = true,
>> .has_ref2 = true,
>> + .has_common_input = false,
>> .clock = 2 * HZ_PER_MHZ,
>> .sinc5_data_rates = ad7173_sinc5_data_rates,
>> .num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
>> @@ -257,6 +266,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
>> .has_temp = true,
>> .has_input_buf = true,
>> .has_int_ref = true,
>> + .has_common_input = true,
>> .clock = 16 * HZ_PER_MHZ,
>> .sinc5_data_rates = ad7175_sinc5_data_rates,
>> .num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
>> @@ -271,6 +281,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
>> .has_input_buf = true,
>> .has_int_ref = true,
>> .has_ref2 = true,
>> + .has_common_input = true,
>> .clock = 16 * HZ_PER_MHZ,
>> .sinc5_data_rates = ad7175_sinc5_data_rates,
>> .num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
>> @@ -285,6 +296,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
>> .has_temp = false,
>> .has_input_buf = false,
>> .has_int_ref = true,
>> + .has_common_input = false,
>> .clock = 16 * HZ_PER_MHZ,
>> .sinc5_data_rates = ad7175_sinc5_data_rates,
>> .num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
>> @@ -298,6 +310,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
>> .has_temp = true,
>> .has_input_buf = true,
>> .has_int_ref = true,
>> + .has_common_input = true,
>> .clock = 16 * HZ_PER_MHZ,
>> .odr_start_value = AD7177_ODR_START_VALUE,
>> .sinc5_data_rates = ad7175_sinc5_data_rates,
>> @@ -920,6 +933,14 @@ static int ad7173_validate_voltage_ain_inputs(struct ad7173_state *st,
>> if (ain[i] < st->info->num_inputs)
>> continue;
>>
>> + if (ain[i] == AD7173_AIN_REF_POS || ain[i] == AD7173_AIN_REF_NEG)
>> + continue;
>> +
>> + if ((ain[i] == AD7173_AIN_COM_IN_POS ||
>> + ain[i] == AD7173_AIN_COM_IN_NEG) &&
>> + st->info->has_common_input)
>> + continue;
>> +
>
> If there is only one valid combination, it seems like these should be
> fixed channels like the temperature input rather than something coming
> from the device tree.
>
As I've said, I do not agree with forcing one channel slot to be used.
I could add a property that spawns this channel. Although as I see under,
I think I'll permit these inputs to be mixed and matched.

> It looks like on AD411x, it is the case that there is only one valid
> option for the reference input in the channel configuration. But in
> the case of AD717x since both REF+ and REF- are listed as possible
> inputs for both AINPOS0 and AINNEG0, it seems like they could be mixed
> and matched with other channels. The datasheet doesn't seem very clear
> on this though.
>
This is imposed artificially, AD411x has the same cross-point mux that
can mix and match all the inputs.

> If it is valid to combine, say AIN0 with REF+ though, then the
> validation would need to be relaxed. But I'm guessing that is not
> actually the case?
>

I think it is the case.

>> return dev_err_probe(dev, -EINVAL,
>> "Input pin number out of range for pair (%d %d).\n",
>> ain[0], ain[1]);
>>
>> --
>> 2.43.0
>>
>>

2024-05-16 16:13:16

[permalink] [raw]

Subject: Re: [PATCH v2 6/9] iio: adc: ad7173: Add ad7173_device_info names

On 16/05/2024 02:32, David Lechner wrote:
> On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay
> <[email protected]> wrote:
>>
>> From: Dumitru Ceclan <[email protected]>
>>
>> Add missing names from the device info struct for 3 models to ensure
>> consistency with the rest of the models.
>>
>
> This affects userspace, right? So probably needs a Fixes: to make sure
> this gets into the 6.10 release?
>
I don't think that it breaks userspace, just creates an additional file.

This creates the file "name" in the iio:deviceX directory that reads the
string. I do not consider the Fixes: tag a necessity. I consider that it
resolves inconsistencies in the _device_info struct.
>> Signed-off-by: Dumitru Ceclan <[email protected]>
>> ---
>> drivers/iio/adc/ad7173.c | 3 +++
>> 1 file changed, 3 insertions(+)
>>
>> diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
>> index 1e9ba3070770..d965b66d4d5a 100644
>> --- a/drivers/iio/adc/ad7173.c
>> +++ b/drivers/iio/adc/ad7173.c
>> @@ -227,6 +227,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
>> .num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
>> },
>> [ID_AD7172_4] = {
>> + .name = "ad7172-4",
>> .id = AD7172_4_ID,
>> .num_inputs = 9,
>> .num_channels = 8,
>> @@ -272,6 +273,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
>> .num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
>> },
>> [ID_AD7175_8] = {
>> + .name = "ad7175-8",
>> .id = AD7175_8_ID,
>> .num_inputs = 17,
>> .num_channels = 16,
>> @@ -302,6 +304,7 @@ static const struct ad7173_device_info ad7173_device_info[] = {
>> .num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
>> },
>> [ID_AD7177_2] = {
>> + .name = "ad7177-2",
>> .id = AD7177_ID,
>> .num_inputs = 5,
>> .num_channels = 4,
>>
>> --
>> 2.43.0
>>
>>

2024-05-16 16:15:30

[permalink] [raw]

Subject: Re: [PATCH v2 0/9] Add support for AD411x

On 16/05/2024 01:35, David Lechner wrote:
> On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay
> <[email protected]> wrote:
>>
>> This patch series adds support for the Analog Devices AD4111, AD4112,
>> AD4114, AD4115, AD4116 within the existing AD7173 driver.
>>
>
> It looks like most of the patches in this series are cleanups and
> fixes of the existing driver unrelated to adding AD411x. Perhaps it
> would be better to split those out into a separate series so we can
> focus on that first? Especially since several of them need to be sent
> as fixes for the v6.10 kernel to avoid breaking usespace or bindings
> in the next release.

Sure

2024-05-16 16:43:29

[permalink] [raw]

Subject: Re: [PATCH v2 1/9] dt-bindings: adc: ad7173: add support for ad411x

On Thu, May 16, 2024 at 10:49 AM Ceclan, Dumitru
<[email protected]> wrote:
>
> On 16/05/2024 01:37, David Lechner wrote:
> > On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay
> > <[email protected]> wrote:
> >>
> >> From: Dumitru Ceclan <[email protected]>
> >>
> >> Add support for: AD4111, AD4112, AD4114, AD4115, AD4116.
> >>
> >> AD411x family ADCs support a VCOM pin, dedicated for single-ended usage.
> >> AD4111/AD4112 support current channels, usage is implemented by
> >> specifying channel reg values bigger than 15.
> >>
> >> Signed-off-by: Dumitru Ceclan <[email protected]>
> >> ---
> >> .../devicetree/bindings/iio/adc/adi,ad7173.yaml | 118 ++++++++++++++++++++-
> >> 1 file changed, 117 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
> >> index ea6cfcd0aff4..6cc3514f5ed8 100644
> >> --- a/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
> >> +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
> >> @@ -19,7 +19,18 @@ description: |
> >> primarily for measurement of signals close to DC but also delivers
> >> outstanding performance with input bandwidths out to ~10kHz.
> >>
> >> + Analog Devices AD411x ADC's:
> >> + The AD411X family encompasses a series of low power, low noise, 24-bit,
> >> + sigma-delta analog-to-digital converters that offer a versatile range of
> >> + specifications. They integrate an analog front end suitable for processing
> >> + fully differential/single-ended and bipolar voltage inputs.
> >> +
> >> Datasheets for supported chips:
> >> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4111.pdf
> >> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4112.pdf
> >> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4114.pdf
> >> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4115.pdf
> >> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD4116.pdf
> >> https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-2.pdf
> >> https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-4.pdf
> >> https://www.analog.com/media/en/technical-documentation/data-sheets/AD7173-8.pdf
> >> @@ -31,6 +42,11 @@ description: |
> >> properties:
> >> compatible:
> >> enum:
> >> + - adi,ad4111
> >> + - adi,ad4112
> >> + - adi,ad4114
> >> + - adi,ad4115
> >> + - adi,ad4116
> >> - adi,ad7172-2
> >> - adi,ad7172-4
> >> - adi,ad7173-8
> >> @@ -129,6 +145,31 @@ patternProperties:
> >> maximum: 15
> >>
> >> diff-channels:
> >> + description: |
> >> + For using current channels specify select the current inputs
> >> + and enable the adi,current-channel property.
> >> +
> >> + Family AD411x supports a dedicated VCOM voltage input.
> >
> > Did you mean VINCOM? Searching the datasheets for "VCOM" comes up empty.
> >
> Yep
> >> + To select it set the second channel to 16.
> >> + (VIN2, VCOM) -> diff-channels = <2 16>
> >
> > Jonathan mentioned this in v1 with regard to the current inputs, but
> > it applies here too. There is a new proposed single-channel property
> > [1] that would be preferred when an input is used as a single-ended or
> > pseudo-differential input (i.e. with VINCOM or ADCIN15).
> >
> > [1]: https://lore.kernel.org/linux-iio/[email protected]/
> >
> Yet here I thought that it was clear from previous conversations that
> we are not really dealing with a single-ended/pseudo-differential input,
> just a differential ADC that can be used in that manner.
>
> We do not have here such a clear cut case as with AD7194, where an input
> is dedicated for single-ended/pseudo usage. Here, the inputs are mix and
> match and single-ended/pseudo is obtainable with other pins than VINCOM/
> ADCIN15.
>
> When configuring channels we are *always* specifying two voltage inputs.
> I strongly disagree using single-channel for voltage channels in these
> families of ADC's.

Yes, sorry, you are right. I forgot that VINCOM isn't actually
electrically different from the other pins (even if the name makes it
seem like it would be).

>
> >> +
> >> + There are special values that can be selected besides the voltage
> >> + analog inputs:
> >> + 21: REF+
> >> + 22: REF−
> >> + Supported only by AD7172-2, AD7172-4, AD7175-2, AD7175-8, AD7177-2:
> >> + 19: ((AVDD1 − AVSS)/5)+
> >> + 20: ((AVDD1 − AVSS)/5)−
> >> + Supported only by AD4111, AD4112:
> >> + 12: IIN3+
> >> + 11: IIN3−
> >> + 13: IIN2+
> >> + 10: IIN2−
> >> + 14: IIN1+
> >> + 9: IIN1−
> >> + 15: IIN0+
> >> + 8: IIN0−
> >
> > I just made a late reply on v1 where Jonathan suggested that the
> > current inputs are differential with a similar comment to this:
> >
> > It doesn't seem to me like current inputs are differential if they are
> > only measuring one current. They take 2 pins because you need a way
> > for current to come in and go back out, but the datasheet calls them
> > single-ended inputs.
> >
> It seemed to me that the conclusion that we arrived to was to expose the
> precise pins that are used in the conversion and document the selection.
>
> Yes, it is a single-ended channel. So revert to the way it was in V1 using
> single-channel?

I'd like to hear Jonathan's opinion on this one.

>
> >> +
> >> items:
> >> minimum: 0
> >> maximum: 31
> >> @@ -154,6 +195,23 @@ patternProperties:
> >> - avdd
> >> default: refout-avss
> >>
> >> + adi,current-channel:
> >> + description: |
> >> + Signal that the selected inputs are current channels.
> >> + Only available on AD4111 and AD4112.
> >> + type: boolean
> >> +
> >> + adi,channel-type:
> >> + description:
> >> + Used to differentiate between different channel types as the device
> >> + register configurations are the same for all usage types.
> >> + $ref: /schemas/types.yaml#/definitions/string
> >> + enum:
> >> + - single-ended
> >> + - pseudo-differential
> >> + - differential
> >> + default: differential
> >> +
> >
> > As suggested above, we should soon have diff-channels and
> > single-channel to differentiate between (fully) differential and
> > single-ended. Do we actually need to differentiate between
> > single-ended and pseudo-differential though?
> >
> Not really, so just a bool differential flag? (this seems weird as we have diff-channels)

Or we need to change the proposed single-channel property to allow two
inputs. I guess we'll see what Johnathan has to say.

>
> > I think the AD4116 datasheet is the only one that uses both of those
> > terms. It gives the examples that for "single-ended" ADCIN15 would be
> > connected to AVSS and for "pseudo-differential" ADCIN15 would be
> > connected to REFOUT (AVSS + 2.5 V). So the only difference seems to be
> > if the voltage on ADCIN15 is == 0V or != 0V.
> >
> In the ad411x yes, over to ad717x it's mixed:
> https://lore.kernel.org/all/[email protected]/
>
> > To make this like other pseudo-differential chips we have done
> > recently, it seems to me like we should have an adcin15-supply
> > property to describe the ADCIN15 input. Then we could use that
> > property to determine single-ended vs. pseudo-differential (if there
> > actually is a need for that) and we wouldn't need the adi,channel-type
> > property.
> >
>
> I agree that we do not need to differentiate between those two.
> But the approach with the supply is too specific, the adi,channel-type
> property is not only for AD4116-ADCIN15, but for all models compatible.
>

Makes sense, especially given the point above that ADCIN15 isn't
really electrically different from other inputs.

> >> required:
> >> - reg
> >> - diff-channels
> >> @@ -166,7 +224,6 @@ allOf:
> >> - $ref: /schemas/spi/spi-peripheral-props.yaml#
> >>
> >> # Only ad7172-4, ad7173-8 and ad7175-8 support vref2
> >> - # Other models have [0-3] channel registers
> >> - if:
> >> properties:
> >> compatible:
> >> @@ -187,6 +244,37 @@ allOf:
> >> - vref
> >> - refout-avss
> >> - avdd
> >> +
> >> + - if:
> >> + properties:
> >> + compatible:
> >> + contains:
> >> + enum:
> >> + - adi,ad4114
> >> + - adi,ad4115
> >> + - adi,ad4116
> >> + - adi,ad7173-8
> >> + - adi,ad7175-8
> >> + then:
> >> + patternProperties:
> >> + "^channel@[0-9a-f]$":
> >> + properties:
> >> + reg:
> >> + maximum: 15
> >
> > As discussed recently in the the very similar ad719x bindings [2], we
> > may have been misunderstanding this limit so far. 15 is a bit
> > artificially low since input pins can be used more than once in
> > different "channels". But that is really an issues with the existing
> > bindings, not just this patch.
> >
> > [2]: https://lore.kernel.org/linux-iio/20240511122955.2372f56e@jic23-huawei/
> >
> >
> In this case there is a 1-1 correspondence between this reg limit and the number
> of channel configuration registers available to the device. Maybe another property
> then reg? Sure...but this limitation fits the current situation.
>
> In addition, the device does not work the same as ad719x. If I understood correctly
> that documentation, the configuration register needs to be rewritten for every different
> input combination. This means that the driver is implemented to overwrite the reg for
> every read. This device, it seems to me, is more in the liking's of write all the channel
> configs at once, then keep using those.
>
> For AD719x yes, it is artificial. Over here we have a clear reason.

I thought they worked nearly the same in this regard since they are
sharing a lot of code via adc/ad_sigma_delta.h, It looks to me like
the channel registers are only set up for a raw read (single channel)
or buffered read (only enabled channels), but maybe I didn't look deep
enough. Anyway, not a big deal to me.

>
> >> +
> >> + - if:
> >> + properties:
> >> + compatible:
> >> + contains:
> >> + enum:
> >> + - adi,ad7172-2
> >> + - adi,ad7175-2
> >> + - adi,ad7176-2
> >> + - adi,ad7177-2
> >> + then:
> >> + patternProperties:
> >> + "^channel@[0-9a-f]$":
> >> + properties:
> >> reg:
> >> maximum: 3
> >>
> >> @@ -210,6 +298,34 @@ allOf:
> >> required:
> >> - adi,reference-select
> >>
> >> + - if:
> >> + properties:
> >> + compatible:
> >> + contains:
> >> + enum:
> >> + - adi,ad4111
> >> + - adi,ad4112
> >> + - adi,ad4114
> >> + - adi,ad4115
> >> + - adi,ad4116
> >> + then:
> >> + properties:
> >> + avdd2-supply: false
> >> +
> >> + - if:
> >> + properties:
> >> + compatible:
> >> + not:
> >> + contains:
> >> + enum:
> >> + - adi,ad4111
> >> + - adi,ad4112
> >> + then:
> >> + patternProperties:
> >> + "^channel@[0-9a-f]$":
> >> + properties:
> >> + adi,current-channel: false
> >> +
> >> - if:
> >> anyOf:
> >> - required: [clock-names]
> >>
> >> --
> >> 2.43.0
> >>
> >>
>

2024-05-16 16:43:54

[permalink] [raw]

Subject: Re: [PATCH v2 6/9] iio: adc: ad7173: Add ad7173_device_info names

On Thu, May 16, 2024 at 11:09 AM Ceclan, Dumitru
<[email protected]> wrote:
>
> On 16/05/2024 02:32, David Lechner wrote:
> > On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay
> > <[email protected]> wrote:
> >>
> >> From: Dumitru Ceclan <[email protected]>
> >>
> >> Add missing names from the device info struct for 3 models to ensure
> >> consistency with the rest of the models.
> >>
> >
> > This affects userspace, right? So probably needs a Fixes: to make sure
> > this gets into the 6.10 release?
> >
> I don't think that it breaks userspace, just creates an additional file.
>
> This creates the file "name" in the iio:deviceX directory that reads the
> string. I do not consider the Fixes: tag a necessity. I consider that it
> resolves inconsistencies in the _device_info struct.

Ah, OK. For some reason, I was thinking that it would default to the
driver name if this was left out.

2024-05-19 16:55:03

[permalink] [raw]

Subject: Re: [PATCH v2 1/9] dt-bindings: adc: ad7173: add support for ad411x

> >
> > >> +
> > >> + There are special values that can be selected besides the voltage
> > >> + analog inputs:
> > >> + 21: REF+
> > >> + 22: REF−
> > >> + Supported only by AD7172-2, AD7172-4, AD7175-2, AD7175-8, AD7177-2:
> > >> + 19: ((AVDD1 − AVSS)/5)+
> > >> + 20: ((AVDD1 − AVSS)/5)−
> > >> + Supported only by AD4111, AD4112:
> > >> + 12: IIN3+
> > >> + 11: IIN3−
> > >> + 13: IIN2+
> > >> + 10: IIN2−
> > >> + 14: IIN1+
> > >> + 9: IIN1−
> > >> + 15: IIN0+
> > >> + 8: IIN0−
> > >
> > > I just made a late reply on v1 where Jonathan suggested that the
> > > current inputs are differential with a similar comment to this:
> > >
> > > It doesn't seem to me like current inputs are differential if they are
> > > only measuring one current. They take 2 pins because you need a way
> > > for current to come in and go back out, but the datasheet calls them
> > > single-ended inputs.
> > >
> > It seemed to me that the conclusion that we arrived to was to expose the
> > precise pins that are used in the conversion and document the selection.
> >
> > Yes, it is a single-ended channel. So revert to the way it was in V1 using
> > single-channel?
>
> I'd like to hear Jonathan's opinion on this one.

Yes. I think we rather went off on a false tangent on this. Any current input
using a shunt is of this form and so far we've treated them as single ended :(
e.g. pac1934 does this for it's sense inputs where there is an external
'sense resitor'. Similar for the stand alone afe driver for a current sense shunt
which is used with a differential voltage input, but presents a single ended
current measurement.

Sorry for misguiding things :(

At the end of this, I don't suppose anyone fancies writing up some notes
on how to describe different types of channel?

>
> >
> > >> +
> > >> items:
> > >> minimum: 0
> > >> maximum: 31
> > >> @@ -154,6 +195,23 @@ patternProperties:
> > >> - avdd
> > >> default: refout-avss
> > >>
> > >> + adi,current-channel:
> > >> + description: |
> > >> + Signal that the selected inputs are current channels.
> > >> + Only available on AD4111 and AD4112.
> > >> + type: boolean

I'm lost. Why do we need this one? Is the channel selection not sufficient
to tell us this?

> > >> +
> > >> + adi,channel-type:
> > >> + description:
> > >> + Used to differentiate between different channel types as the device
> > >> + register configurations are the same for all usage types.
> > >> + $ref: /schemas/types.yaml#/definitions/string
> > >> + enum:
> > >> + - single-ended
> > >> + - pseudo-differential
> > >> + - differential
> > >> + default: differential
> > >> +
> > >
> > > As suggested above, we should soon have diff-channels and
> > > single-channel to differentiate between (fully) differential and
> > > single-ended. Do we actually need to differentiate between
> > > single-ended and pseudo-differential though?
> > >
> > Not really, so just a bool differential flag? (this seems weird as we have diff-channels)
>
> Or we need to change the proposed single-channel property to allow two
> inputs. I guess we'll see what Johnathan has to say.

I think single ended fits better for the current channels with just one
parameter.

2024-05-19 16:58:25

[permalink] [raw]

Subject: Re: [PATCH v2 3/9] iio: adc: ad7173: refactor channel configuration parsing

On Tue, 14 May 2024 10:22:48 +0300
Dumitru Ceclan via B4 Relay <[email protected]> wrote:

> From: Dumitru Ceclan <[email protected]>
>
> Move configurations regarding number of channels from
> *_fw_parse_device_config to *_fw_parse_channel_config.
>
> Suggested-by: Jonathan Cameron <[email protected]>
> Link: https://lore.kernel.org/all/20240303162148.3ad91aa2@jic23-huawei/
>
These are all part of the tag block so no blank line here.
Having one will break some scripts that parse these blocks and

> Reviewed-by: David Lechner <[email protected]>
> Signed-off-by: Dumitru Ceclan <[email protected]>

2024-05-19 17:09:11

[permalink] [raw]

Subject: Re: [PATCH v2 7/9] iio: adc: ad7173: Remove index from temp channel

On Wed, 15 May 2024 18:34:17 -0500
David Lechner <[email protected]> wrote:

> On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay
> <[email protected]> wrote:
> >
> > From: Dumitru Ceclan <[email protected]>
> >
> > Temperature channel is unique per device, index is not needed.
> >
> > This is breaking userspace: as main driver has not reached mainline yet
> > it won't affect users as there are none.
>
> But it is queued up, so probably need a Fixes: here to make sure it
> makes it into the release.
Yes. We can fix this but it will need to go as a fix during the rc cycles
rather than wait for the next merge window like the rest of this series.

Jonathan

>
> >
> > Signed-off-by: Dumitru Ceclan <[email protected]>
> > ---
> > drivers/iio/adc/ad7173.c | 1 -
> > 1 file changed, 1 deletion(-)
> >
> > diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
> > index d965b66d4d5a..d66b47e1a186 100644
> > --- a/drivers/iio/adc/ad7173.c
> > +++ b/drivers/iio/adc/ad7173.c
> > @@ -828,7 +828,6 @@ static const struct iio_chan_spec ad7173_channel_template = {
> >
> > static const struct iio_chan_spec ad7173_temp_iio_channel_template = {
> > .type = IIO_TEMP,
> > - .indexed = 1,
> > .channel = AD7173_AIN_TEMP_POS,
> > .channel2 = AD7173_AIN_TEMP_NEG,
> > .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> >
> > --
> > 2.43.0
> >
> >

2024-05-19 17:10:02

[permalink] [raw]

Subject: Re: [PATCH v2 6/9] iio: adc: ad7173: Add ad7173_device_info names

On Thu, 16 May 2024 11:43:17 -0500
David Lechner <[email protected]> wrote:

> On Thu, May 16, 2024 at 11:09 AM Ceclan, Dumitru
> <[email protected]> wrote:
> >
> > On 16/05/2024 02:32, David Lechner wrote:
> > > On Tue, May 14, 2024 at 2:23 AM Dumitru Ceclan via B4 Relay
> > > <[email protected]> wrote:
> > >>
> > >> From: Dumitru Ceclan <[email protected]>
> > >>
> > >> Add missing names from the device info struct for 3 models to ensure
> > >> consistency with the rest of the models.
> > >>
> > >
> > > This affects userspace, right? So probably needs a Fixes: to make sure
> > > this gets into the 6.10 release?
> > >
> > I don't think that it breaks userspace, just creates an additional file.
> >
> > This creates the file "name" in the iio:deviceX directory that reads the
> > string. I do not consider the Fixes: tag a necessity. I consider that it
> > resolves inconsistencies in the _device_info struct.
>
> Ah, OK. For some reason, I was thinking that it would default to the
> driver name if this was left out.

Hmm. I'd be tempted to take this a fix as some userspace code relies
on that name being present and it is unusual to not see it.

Jonathan

2024-05-19 17:14:12

[permalink] [raw]

Subject: Re: [PATCH v2 8/9] iio: adc: ad7173: Add support for AD411x devices

On Tue, 14 May 2024 10:22:53 +0300
Dumitru Ceclan via B4 Relay <[email protected]> wrote:

> From: Dumitru Ceclan <[email protected]>
>
> Add support for AD4111/AD4112/AD4114/AD4115/AD4116.
>
> The AD411X family encompasses a series of low power, low noise, 24-bit,
> sigma-delta analog-to-digital converters that offer a versatile range of
> specifications.
>
> This family of ADCs integrates an analog front end suitable for processing
> both fully differential and single-ended, bipolar voltage inputs
> addressing a wide array of industrial and instrumentation requirements.
>
> - All ADCs have inputs with a precision voltage divider with a division
> ratio of 10.
> - AD4116 has 5 low level inputs without a voltage divider.
> - AD4111 and AD4112 support current inputs (0 mA to 20 mA) using a 50ohm
> shunt resistor.
>
> Signed-off-by: Dumitru Ceclan <[email protected]>
A couple of trivial things inline. Otherwise lgtm

> @@ -1058,17 +1296,26 @@ static int ad7173_fw_parse_channel_config(struct iio_dev *indio_dev)
> chan->scan_index = chan_index;
> chan->channel = ain[0];
> chan->channel2 = ain[1];
> - chan->differential = true;
> -
> chan_st_priv->ain = AD7173_CH_ADDRESS(ain[0], ain[1]);
> chan_st_priv->chan_reg = chan_index;
> - chan_st_priv->cfg.input_buf = st->info->has_input_buf;
> chan_st_priv->cfg.odr = 0;
> -
> chan_st_priv->cfg.bipolar = fwnode_property_read_bool(child, "bipolar");
> +
> if (chan_st_priv->cfg.bipolar)
> chan->info_mask_separate |= BIT(IIO_CHAN_INFO_OFFSET);
>
> + if (is_current_chan)
> + chan->type = IIO_CURRENT;
> + else
> + chan_st_priv->cfg.input_buf = st->info->has_input_buf;
> +
> + ret = fwnode_property_match_property_string(child,
> + "adi,channel-type",
> + ad7173_channel_types,
> + ARRAY_SIZE(ad7173_channel_types));
> + chan->differential = (ret < 0 || ret == AD7173_CHAN_DIFFERENTIAL)
> + ? true : false;

That's not a boolean. So better to set 1 or 0.

> +MODULE_DESCRIPTION("Analog Devices AD717x and AD411x ADC driver");

I'm scared of wildcards even in descriptive fields as they often end up covering
something unintended. I'd just go with 'and similar'.

> MODULE_LICENSE("GPL");
>

2024-05-19 19:17:44