[PATCH 2/4] iio: adc: ad4000: Add timestamp channel

Marcelo Schmitt posted 4 patches 1 week, 1 day ago
There is a newer version of this series
[PATCH 2/4] iio: adc: ad4000: Add timestamp channel
Posted by Marcelo Schmitt 1 week, 1 day ago
The ADC data is pushed to the IIO buffer along with timestamp but no
timestamp channel was provided to retried the time data.
Add a timestamp channel to provide sample capture time.

Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
---
I was about to reply to the patches the other week but waited thinking I
would be able to test them on time.
My initial intent was to provide timestamps for ADC readings, but I didn't
realize an IIO timestamp channel would be needed (silly me).
David, do you want a Suggested-by tag in this one?

 drivers/iio/adc/ad4000.c | 98 +++++++++++++++++++++++-----------------
 1 file changed, 56 insertions(+), 42 deletions(-)

diff --git a/drivers/iio/adc/ad4000.c b/drivers/iio/adc/ad4000.c
index b3b82535f5c1..21731c4d31ee 100644
--- a/drivers/iio/adc/ad4000.c
+++ b/drivers/iio/adc/ad4000.c
@@ -49,6 +49,7 @@
 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |				\
 			      BIT(IIO_CHAN_INFO_SCALE),				\
 	.info_mask_separate_available = _reg_access ? BIT(IIO_CHAN_INFO_SCALE) : 0,\
+	.scan_index = 0,							\
 	.scan_type = {								\
 		.sign = _sign,							\
 		.realbits = _real_bits,						\
@@ -62,6 +63,12 @@
 	__AD4000_DIFF_CHANNEL((_sign), (_real_bits),				\
 				     ((_real_bits) > 16 ? 32 : 16), (_reg_access))
 
+#define AD4000_DIFF_CHANNELS(_sign, _real_bits, _reg_access)			\
+{										\
+	AD4000_DIFF_CHANNEL(_sign, _real_bits, _reg_access),			\
+	IIO_CHAN_SOFT_TIMESTAMP(1)						\
+}
+
 #define __AD4000_PSEUDO_DIFF_CHANNEL(_sign, _real_bits, _storage_bits, _reg_access)\
 {										\
 	.type = IIO_VOLTAGE,							\
@@ -71,6 +78,7 @@
 			      BIT(IIO_CHAN_INFO_SCALE) |			\
 			      BIT(IIO_CHAN_INFO_OFFSET),			\
 	.info_mask_separate_available = _reg_access ? BIT(IIO_CHAN_INFO_SCALE) : 0,\
+	.scan_index = 0,							\
 	.scan_type = {								\
 		.sign = _sign,							\
 		.realbits = _real_bits,						\
@@ -84,6 +92,12 @@
 	__AD4000_PSEUDO_DIFF_CHANNEL((_sign), (_real_bits),			\
 				     ((_real_bits) > 16 ? 32 : 16), (_reg_access))
 
+#define AD4000_PSEUDO_DIFF_CHANNELS(_sign, _real_bits, _reg_access)		\
+{										\
+	AD4000_PSEUDO_DIFF_CHANNEL(_sign, _real_bits, _reg_access),		\
+	IIO_CHAN_SOFT_TIMESTAMP(1)						\
+}
+
 static const char * const ad4000_power_supplies[] = {
 	"vdd", "vio"
 };
@@ -110,106 +124,106 @@ static const int ad4000_gains[] = {
 
 struct ad4000_chip_info {
 	const char *dev_name;
-	struct iio_chan_spec chan_spec;
-	struct iio_chan_spec reg_access_chan_spec;
+	struct iio_chan_spec chan_spec[2];
+	struct iio_chan_spec reg_access_chan_spec[2];
 	bool has_hardware_gain;
 };
 
 static const struct ad4000_chip_info ad4000_chip_info = {
 	.dev_name = "ad4000",
-	.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 0),
-	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 1),
+	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 0),
+	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 1),
 };
 
 static const struct ad4000_chip_info ad4001_chip_info = {
 	.dev_name = "ad4001",
-	.chan_spec = AD4000_DIFF_CHANNEL('s', 16, 0),
-	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 16, 1),
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 16, 0),
+	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 16, 1),
 };
 
 static const struct ad4000_chip_info ad4002_chip_info = {
 	.dev_name = "ad4002",
-	.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 0),
-	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 1),
+	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 18, 0),
+	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 18, 1),
 };
 
 static const struct ad4000_chip_info ad4003_chip_info = {
 	.dev_name = "ad4003",
-	.chan_spec = AD4000_DIFF_CHANNEL('s', 18, 0),
-	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 18, 1),
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 18, 0),
+	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 18, 1),
 };
 
 static const struct ad4000_chip_info ad4004_chip_info = {
 	.dev_name = "ad4004",
-	.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 0),
-	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 1),
+	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 0),
+	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 1),
 };
 
 static const struct ad4000_chip_info ad4005_chip_info = {
 	.dev_name = "ad4005",
-	.chan_spec = AD4000_DIFF_CHANNEL('s', 16, 0),
-	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 16, 1),
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 16, 0),
+	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 16, 1),
 };
 
 static const struct ad4000_chip_info ad4006_chip_info = {
 	.dev_name = "ad4006",
-	.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 0),
-	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 1),
+	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 18, 0),
+	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 18, 1),
 };
 
 static const struct ad4000_chip_info ad4007_chip_info = {
 	.dev_name = "ad4007",
-	.chan_spec = AD4000_DIFF_CHANNEL('s', 18, 0),
-	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 18, 1),
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 18, 0),
+	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 18, 1),
 };
 
 static const struct ad4000_chip_info ad4008_chip_info = {
 	.dev_name = "ad4008",
-	.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 0),
-	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 1),
+	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 0),
+	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 1),
 };
 
 static const struct ad4000_chip_info ad4010_chip_info = {
 	.dev_name = "ad4010",
-	.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 0),
-	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 1),
+	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 18, 0),
+	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 18, 1),
 };
 
 static const struct ad4000_chip_info ad4011_chip_info = {
 	.dev_name = "ad4011",
-	.chan_spec = AD4000_DIFF_CHANNEL('s', 18, 0),
-	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 18, 1),
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 18, 0),
+	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 18, 1),
 };
 
 static const struct ad4000_chip_info ad4020_chip_info = {
 	.dev_name = "ad4020",
-	.chan_spec = AD4000_DIFF_CHANNEL('s', 20, 0),
-	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 20, 1),
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 20, 0),
+	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 20, 1),
 };
 
 static const struct ad4000_chip_info ad4021_chip_info = {
 	.dev_name = "ad4021",
-	.chan_spec = AD4000_DIFF_CHANNEL('s', 20, 0),
-	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 20, 1),
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 20, 0),
+	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 20, 1),
 };
 
 static const struct ad4000_chip_info ad4022_chip_info = {
 	.dev_name = "ad4022",
-	.chan_spec = AD4000_DIFF_CHANNEL('s', 20, 0),
-	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 20, 1),
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 20, 0),
+	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 20, 1),
 };
 
 static const struct ad4000_chip_info adaq4001_chip_info = {
 	.dev_name = "adaq4001",
-	.chan_spec = AD4000_DIFF_CHANNEL('s', 16, 0),
-	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 16, 1),
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 16, 0),
+	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 16, 1),
 	.has_hardware_gain = true,
 };
 
 static const struct ad4000_chip_info adaq4003_chip_info = {
 	.dev_name = "adaq4003",
-	.chan_spec = AD4000_DIFF_CHANNEL('s', 18, 0),
-	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 18, 1),
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 18, 0),
+	.reg_access_chan_spec = AD4000_DIFF_CHANNELS('s', 18, 1),
 	.has_hardware_gain = true,
 };
 
@@ -591,7 +605,7 @@ static int ad4000_probe(struct spi_device *spi)
 	switch (st->sdi_pin) {
 	case AD4000_SDI_MOSI:
 		indio_dev->info = &ad4000_reg_access_info;
-		indio_dev->channels = &chip->reg_access_chan_spec;
+		indio_dev->channels = chip->reg_access_chan_spec;
 
 		/*
 		 * In "3-wire mode", the ADC SDI line must be kept high when
@@ -603,7 +617,7 @@ static int ad4000_probe(struct spi_device *spi)
 		if (ret < 0)
 			return ret;
 
-		ret = ad4000_prepare_3wire_mode_message(st, indio_dev->channels);
+		ret = ad4000_prepare_3wire_mode_message(st, &indio_dev->channels[0]);
 		if (ret)
 			return ret;
 
@@ -614,16 +628,16 @@ static int ad4000_probe(struct spi_device *spi)
 		break;
 	case AD4000_SDI_VIO:
 		indio_dev->info = &ad4000_info;
-		indio_dev->channels = &chip->chan_spec;
-		ret = ad4000_prepare_3wire_mode_message(st, indio_dev->channels);
+		indio_dev->channels = chip->chan_spec;
+		ret = ad4000_prepare_3wire_mode_message(st, &indio_dev->channels[0]);
 		if (ret)
 			return ret;
 
 		break;
 	case AD4000_SDI_CS:
 		indio_dev->info = &ad4000_info;
-		indio_dev->channels = &chip->chan_spec;
-		ret = ad4000_prepare_4wire_mode_message(st, indio_dev->channels);
+		indio_dev->channels = chip->chan_spec;
+		ret = ad4000_prepare_4wire_mode_message(st, &indio_dev->channels[0]);
 		if (ret)
 			return ret;
 
@@ -637,7 +651,7 @@ static int ad4000_probe(struct spi_device *spi)
 	}
 
 	indio_dev->name = chip->dev_name;
-	indio_dev->num_channels = 1;
+	indio_dev->num_channels = 2;
 
 	ret = devm_mutex_init(dev, &st->lock);
 	if (ret)
@@ -658,7 +672,7 @@ static int ad4000_probe(struct spi_device *spi)
 		}
 	}
 
-	ad4000_fill_scale_tbl(st, indio_dev->channels);
+	ad4000_fill_scale_tbl(st, &indio_dev->channels[0]);
 
 	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
 					      &iio_pollfunc_store_time,
-- 
2.45.2
Re: [PATCH 2/4] iio: adc: ad4000: Add timestamp channel
Posted by David Lechner 1 week ago
On 11/14/24 5:50 PM, Marcelo Schmitt wrote:
> The ADC data is pushed to the IIO buffer along with timestamp but no
> timestamp channel was provided to retried the time data.
> Add a timestamp channel to provide sample capture time.
> 
> Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
> ---
> I was about to reply to the patches the other week but waited thinking I
> would be able to test them on time.
> My initial intent was to provide timestamps for ADC readings, but I didn't
> realize an IIO timestamp channel would be needed (silly me).
> David, do you want a Suggested-by tag in this one?

I supposed that would make more sense than Reported-by: if we are
calling this a feature rather than a bug. Also,

Reviewed-by: David Lechner <dlechner@baylibre.com>