[PATCH v2 2/4] iio: adc: ad7768-1: introduce chip info for future multidevice support

[PATCH v2 2/4] iio: adc: ad7768-1: introduce chip info for future multidevice support

[Jonathan Santos]

Add Chip info struct in SPI device to store channel information for
each supported part.

Signed-off-by: Jonathan Santos <Jonathan.Santos@analog.com>
---
v2 Changes:
* removed AD7768_CHAN_INFO_NONE macro.
* reordered fields in ad7768_chip_info struct.
* removed trailing comma.
---
 drivers/iio/adc/ad7768-1.c | 75 ++++++++++++++++++++++++++------------
 1 file changed, 52 insertions(+), 23 deletions(-)

diff --git a/drivers/iio/adc/ad7768-1.c b/drivers/iio/adc/ad7768-1.c
index a2e061f0cb08..83b0907b068d 100644
--- a/drivers/iio/adc/ad7768-1.c
+++ b/drivers/iio/adc/ad7768-1.c
@@ -213,6 +213,13 @@ static const struct iio_scan_type ad7768_scan_type[] = {
 	},
 };
 
+struct ad7768_chip_info {
+	const char *name;
+	const unsigned long *available_masks;
+	const struct iio_chan_spec *channel_spec;
+	int num_channels;
+};
+
 struct ad7768_state {
 	struct spi_device *spi;
 	struct regmap *regmap;
@@ -234,6 +241,7 @@ struct ad7768_state {
 	struct gpio_desc *gpio_reset;
 	const char *labels[AD7768_MAX_CHANNELS];
 	struct gpio_chip gpiochip;
+	const struct ad7768_chip_info *chip;
 	bool en_spi_sync;
 	/*
 	 * DMA (thus cache coherency maintenance) may require the
@@ -750,24 +758,27 @@ static const struct iio_chan_spec_ext_info ad7768_ext_info[] = {
 	{ }
 };
 
+#define AD7768_CHAN(_idx, _msk_avail) {	\
+	.type = IIO_VOLTAGE,\
+	.info_mask_separate_available = _msk_avail,\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
+			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) | \
+			BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),\
+	.info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),\
+	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+	.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
+	.ext_info = ad7768_ext_info,\
+	.indexed = 1,\
+	.channel = _idx,\
+	.scan_index = _idx,\
+	.has_ext_scan_type = 1,\
+	.ext_scan_type = ad7768_scan_type,\
+	.num_ext_scan_type = ARRAY_SIZE(ad7768_scan_type),\
+}
+
 static const struct iio_chan_spec ad7768_channels[] = {
-	{
-		.type = IIO_VOLTAGE,
-		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
-		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |
-					    BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) |
-					    BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
-		.info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
-		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
-		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),
-		.ext_info = ad7768_ext_info,
-		.indexed = 1,
-		.channel = 0,
-		.scan_index = 0,
-		.has_ext_scan_type = 1,
-		.ext_scan_type = ad7768_scan_type,
-		.num_ext_scan_type = ARRAY_SIZE(ad7768_scan_type),
-	},
+	AD7768_CHAN(0, 0),
 };
 
 static int ad7768_read_raw(struct iio_dev *indio_dev,
@@ -1334,6 +1345,18 @@ static int ad7768_register_regulators(struct device *dev, struct ad7768_state *s
 	return 0;
 }
 
+static const unsigned long ad7768_channel_masks[] = {
+	BIT(0),
+	0
+};
+
+static const struct ad7768_chip_info ad7768_chip_info = {
+	.name = "ad7768-1",
+	.channel_spec = ad7768_channels,
+	.num_channels = ARRAY_SIZE(ad7768_channels),
+	.available_masks = ad7768_channel_masks,
+};
+
 static int ad7768_probe(struct spi_device *spi)
 {
 	struct ad7768_state *st;
@@ -1392,9 +1415,15 @@ static int ad7768_probe(struct spi_device *spi)
 
 	st->mclk_freq = clk_get_rate(st->mclk);
 
-	indio_dev->channels = ad7768_channels;
-	indio_dev->num_channels = ARRAY_SIZE(ad7768_channels);
-	indio_dev->name = spi_get_device_id(spi)->name;
+	st->chip = spi_get_device_match_data(spi);
+	if (!st->chip)
+		return dev_err_probe(&spi->dev, -ENODEV,
+				     "Could not find chip info data\n");
+
+	indio_dev->channels = st->chip->channel_spec;
+	indio_dev->num_channels = st->chip->num_channels;
+	indio_dev->available_scan_masks = st->chip->available_masks;
+	indio_dev->name = st->chip->name;
 	indio_dev->info = &ad7768_info;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 
@@ -1411,7 +1440,7 @@ static int ad7768_probe(struct spi_device *spi)
 
 	init_completion(&st->completion);
 
-	ret = ad7768_set_channel_label(indio_dev, ARRAY_SIZE(ad7768_channels));
+	ret = ad7768_set_channel_label(indio_dev, st->chip->num_channels);
 	if (ret)
 		return ret;
 
@@ -1430,13 +1459,13 @@ static int ad7768_probe(struct spi_device *spi)
 }
 
 static const struct spi_device_id ad7768_id_table[] = {
-	{ "ad7768-1", 0 },
+	{ "ad7768-1", (kernel_ulong_t)&ad7768_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(spi, ad7768_id_table);
 
 static const struct of_device_id ad7768_of_match[] = {
-	{ .compatible = "adi,ad7768-1" },
+	{ .compatible = "adi,ad7768-1", .data = &ad7768_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, ad7768_of_match);
-- 
2.34.1

Re: [PATCH v2 2/4] iio: adc: ad7768-1: introduce chip info for future multidevice support

[Jonathan Cameron]

On Sun, 24 Aug 2025 01:09:53 -0300
Jonathan Santos <Jonathan.Santos@analog.com> wrote:

> Add Chip info struct in SPI device to store channel information for
> each supported part.
> 
> Signed-off-by: Jonathan Santos <Jonathan.Santos@analog.com>
> ---
> v2 Changes:
> * removed AD7768_CHAN_INFO_NONE macro.
> * reordered fields in ad7768_chip_info struct.
> * removed trailing comma.
> ---
>  drivers/iio/adc/ad7768-1.c | 75 ++++++++++++++++++++++++++------------
>  1 file changed, 52 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/iio/adc/ad7768-1.c b/drivers/iio/adc/ad7768-1.c
> index a2e061f0cb08..83b0907b068d 100644
> --- a/drivers/iio/adc/ad7768-1.c
> +++ b/drivers/iio/adc/ad7768-1.c
> @@ -213,6 +213,13 @@ static const struct iio_scan_type ad7768_scan_type[] = {
>  	},
>  };
>  
> +struct ad7768_chip_info {
> +	const char *name;
> +	const unsigned long *available_masks;
> +	const struct iio_chan_spec *channel_spec;
> +	int num_channels;
> +};
> +
>  struct ad7768_state {
>  	struct spi_device *spi;
>  	struct regmap *regmap;
> @@ -234,6 +241,7 @@ struct ad7768_state {
>  	struct gpio_desc *gpio_reset;
>  	const char *labels[AD7768_MAX_CHANNELS];
>  	struct gpio_chip gpiochip;
> +	const struct ad7768_chip_info *chip;
>  	bool en_spi_sync;
>  	/*
>  	 * DMA (thus cache coherency maintenance) may require the
> @@ -750,24 +758,27 @@ static const struct iio_chan_spec_ext_info ad7768_ext_info[] = {
>  	{ }
>  };
>  
> +#define AD7768_CHAN(_idx, _msk_avail) {	\

Check for consistency.  looks like you were aiming for 1 space before \ but didn't
get it the same everywhere?

> +	.type = IIO_VOLTAGE,\
> +	.info_mask_separate_available = _msk_avail,\
> +	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),\
> +	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
> +			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) | \
> +			BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),\
> +	.info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),\
> +	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> +	.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
> +	.ext_info = ad7768_ext_info,\
> +	.indexed = 1,\
> +	.channel = _idx,\
> +	.scan_index = _idx,\
> +	.has_ext_scan_type = 1,\
> +	.ext_scan_type = ad7768_scan_type,\
> +	.num_ext_scan_type = ARRAY_SIZE(ad7768_scan_type),\
> +}
> +
>  static const struct iio_chan_spec ad7768_channels[] = {
> -	{
> -		.type = IIO_VOLTAGE,
> -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> -		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |
> -					    BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) |
> -					    BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
> -		.info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
> -		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
> -		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),
> -		.ext_info = ad7768_ext_info,
> -		.indexed = 1,
> -		.channel = 0,
> -		.scan_index = 0,
> -		.has_ext_scan_type = 1,
> -		.ext_scan_type = ad7768_scan_type,
> -		.num_ext_scan_type = ARRAY_SIZE(ad7768_scan_type),
> -	},
> +	AD7768_CHAN(0, 0),
>  };
>  
>  static int ad7768_read_raw(struct iio_dev *indio_dev,
> @@ -1334,6 +1345,18 @@ static int ad7768_register_regulators(struct device *dev, struct ad7768_state *s
>  	return 0;
>  }
>  
> +static const unsigned long ad7768_channel_masks[] = {
> +	BIT(0),

That doesn't make a lot of sense. Don't provide one for devices with
only one channel.  Leave it set to NULL and everything should just work.

> +	0
> +};