[PATCH 07/12] iio: adc: ad9467: fix scale setting

Nuno Sa via B4 Relay
2023-11-21T10:18:02Z

From: Nuno Sa <nuno.sa@analog.com>

When reading in_voltage_scale we can get something like:

root@analog:/sys/bus/iio/devices/iio:device2# cat in_voltage_scale
0.038146

However, when reading the available options:

root@analog:/sys/bus/iio/devices/iio:device2# cat
in_voltage_scale_available
2000.000000 2100.000006 2200.000007 2300.000008 2400.000009 2500.000010

which does not make sense. Moreover, when trying to set a new scale we
get an error because there's no call to __ad9467_get_scale() to give us
values as given when reading in_voltage_scale. Fix it by computing the
available scales during probe and properly pass the list when
.read_available() is called.

While at it, change to use .read_available() from iio_info. Also note
that to properly fix this, adi-axi-adc.c has to be changed accordingly.

Fixes: ad6797120238 ("iio: adc: ad9467: add support AD9467 ADC")
Signed-off-by: Nuno Sa <nuno.sa@analog.com>
---
drivers/iio/adc/ad9467.c | 47 +++++++++++++++++++++++
drivers/iio/adc/adi-axi-adc.c | 74 ++++++++-----------------------------
include/linux/iio/adc/adi-axi-adc.h | 4 ++
3 files changed, 66 insertions(+), 59 deletions(-)

diff --git a/drivers/iio/adc/ad9467.c b/drivers/iio/adc/ad9467.c
index 91821dee03b7..df4c21248226 100644
--- a/drivers/iio/adc/ad9467.c
+++ b/drivers/iio/adc/ad9467.c
@@ -120,6 +120,7 @@ struct ad9467_state {
struct spi_device *spi;
struct clk *clk;
unsigned int output_mode;
+ unsigned int (*scales)[2];

struct gpio_desc *pwrdown_gpio;
/* protect against concurrent accesses to the device */
@@ -216,6 +217,7 @@ static void __ad9467_get_scale(struct adi_axi_adc_conv *conv, int index,
.channel = _chan, \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SCALE), \
.scan_index = _si, \
.scan_type = { \
.sign = _sign, \
@@ -369,6 +371,26 @@ static int ad9467_write_raw(struct adi_axi_adc_conv *conv,
}
}

+static int ad9467_read_avail(struct adi_axi_adc_conv *conv,
+ struct iio_chan_spec const *chan,
+ const int **vals, int *type, int *length,
+ long mask)
+{
+ const struct adi_axi_adc_chip_info *info = conv->chip_info;
+ struct ad9467_state *st = adi_axi_adc_conv_priv(conv);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SCALE:
+ *vals = (const int *)st->scales;
+ *type = IIO_VAL_INT_PLUS_MICRO;
+ /* Values are stored in a 2D matrix */
+ *length = info->num_scales * 2;
+ return IIO_AVAIL_LIST;
+ default:
+ return -EINVAL;
+ }
+}
+
static int ad9467_outputmode_set(struct spi_device *spi, unsigned int mode)
{
int ret;
@@ -381,6 +403,26 @@ static int ad9467_outputmode_set(struct spi_device *spi, unsigned int mode)
AN877_ADC_TRANSFER_SYNC);
}

+static int ad9467_scale_fill(struct adi_axi_adc_conv *conv)
+{
+ const struct adi_axi_adc_chip_info *info = conv->chip_info;
+ struct ad9467_state *st = adi_axi_adc_conv_priv(conv);
+ unsigned int i, val1, val2;
+
+ st->scales = devm_kcalloc(&st->spi->dev, ARRAY_SIZE(*st->scales),
+ info->num_scales, GFP_KERNEL);
+ if (!st->scales)
+ return -ENOMEM;
+
+ for (i = 0; i < info->num_scales * 2; i++) {
+ __ad9467_get_scale(conv, i, &val1, &val2);
+ st->scales[i][0] = val1;
+ st->scales[i][1] = val2;
+ }
+
+ return 0;
+}
+
static int ad9467_preenable_setup(struct adi_axi_adc_conv *conv)
{
struct ad9467_state *st = adi_axi_adc_conv_priv(conv);
@@ -441,6 +483,10 @@ static int ad9467_probe(struct spi_device *spi)

conv->chip_info = &info->axi_adc_info;

+ ret = ad9467_scale_fill(conv);
+ if (ret)
+ return ret;
+
id = ad9467_spi_read(spi, AN877_ADC_REG_CHIP_ID);
if (id != conv->chip_info->id) {
dev_err(&spi->dev, "Mismatch CHIP_ID, got 0x%X, expected 0x%X\n",
@@ -451,6 +497,7 @@ static int ad9467_probe(struct spi_device *spi)
conv->reg_access = ad9467_reg_access;
conv->write_raw = ad9467_write_raw;
conv->read_raw = ad9467_read_raw;
+ conv->read_avail = ad9467_read_avail;
conv->preenable_setup = ad9467_preenable_setup;

st->output_mode = info->default_output_mode |
diff --git a/drivers/iio/adc/adi-axi-adc.c b/drivers/iio/adc/adi-axi-adc.c
index aff0532a974a..ae83ada7f9f2 100644
--- a/drivers/iio/adc/adi-axi-adc.c
+++ b/drivers/iio/adc/adi-axi-adc.c
@@ -144,6 +144,20 @@ static int adi_axi_adc_write_raw(struct iio_dev *indio_dev,
return conv->write_raw(conv, chan, val, val2, mask);
}

+static int adi_axi_adc_read_avail(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ const int **vals, int *type, int *length,
+ long mask)
+{
+ struct adi_axi_adc_state *st = iio_priv(indio_dev);
+ struct adi_axi_adc_conv *conv = &st->client->conv;
+
+ if (!conv->read_avail)
+ return -EOPNOTSUPP;
+
+ return conv->read_avail(conv, chan, vals, type, length, mask);
+}
+
static int adi_axi_adc_update_scan_mode(struct iio_dev *indio_dev,
const unsigned long *scan_mask)
{
@@ -228,69 +242,11 @@ struct adi_axi_adc_conv *devm_adi_axi_adc_conv_register(struct device *dev,
}
EXPORT_SYMBOL_NS_GPL(devm_adi_axi_adc_conv_register, IIO_ADI_AXI);

-static ssize_t in_voltage_scale_available_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev *indio_dev = dev_to_iio_dev(dev);
- struct adi_axi_adc_state *st = iio_priv(indio_dev);
- struct adi_axi_adc_conv *conv = &st->client->conv;
- size_t len = 0;
- int i;
-
- for (i = 0; i < conv->chip_info->num_scales; i++) {
- const unsigned int *s = conv->chip_info->scale_table[i];
-
- len += scnprintf(buf + len, PAGE_SIZE - len,
- "%u.%06u ", s[0], s[1]);
- }
- buf[len - 1] = '\n';
-
- return len;
-}
-
-static IIO_DEVICE_ATTR_RO(in_voltage_scale_available, 0);
-
-enum {
- ADI_AXI_ATTR_SCALE_AVAIL,
-};
-
-#define ADI_AXI_ATTR(_en_, _file_) \
- [ADI_AXI_ATTR_##_en_] = &iio_dev_attr_##_file_.dev_attr.attr
-
-static struct attribute *adi_axi_adc_attributes[] = {
- ADI_AXI_ATTR(SCALE_AVAIL, in_voltage_scale_available),
- NULL
-};
-
-static umode_t axi_adc_attr_is_visible(struct kobject *kobj,
- struct attribute *attr, int n)
-{
- struct device *dev = kobj_to_dev(kobj);
- struct iio_dev *indio_dev = dev_to_iio_dev(dev);
- struct adi_axi_adc_state *st = iio_priv(indio_dev);
- struct adi_axi_adc_conv *conv = &st->client->conv;
-
- switch (n) {
- case ADI_AXI_ATTR_SCALE_AVAIL:
- if (!conv->chip_info->num_scales)
- return 0;
- return attr->mode;
- default:
- return attr->mode;
- }
-}
-
-static const struct attribute_group adi_axi_adc_attribute_group = {
- .attrs = adi_axi_adc_attributes,
- .is_visible = axi_adc_attr_is_visible,
-};
-
static const struct iio_info adi_axi_adc_info = {
.read_raw = &adi_axi_adc_read_raw,
.write_raw = &adi_axi_adc_write_raw,
- .attrs = &adi_axi_adc_attribute_group,
.update_scan_mode = &adi_axi_adc_update_scan_mode,
+ .read_avail = &adi_axi_adc_read_avail,
};

static const struct adi_axi_adc_core_info adi_axi_adc_10_0_a_info = {
diff --git a/include/linux/iio/adc/adi-axi-adc.h b/include/linux/iio/adc/adi-axi-adc.h
index 52620e5b8052..b7904992d561 100644
--- a/include/linux/iio/adc/adi-axi-adc.h
+++ b/include/linux/iio/adc/adi-axi-adc.h
@@ -41,6 +41,7 @@ struct adi_axi_adc_chip_info {
* @reg_access IIO debugfs_reg_access hook for the client ADC
* @read_raw IIO read_raw hook for the client ADC
* @write_raw IIO write_raw hook for the client ADC
+ * @read_avail IIO read_avail hook for the client ADC
*/
struct adi_axi_adc_conv {
const struct adi_axi_adc_chip_info *chip_info;
@@ -54,6 +55,9 @@ struct adi_axi_adc_conv {
int (*write_raw)(struct adi_axi_adc_conv *conv,
struct iio_chan_spec const *chan,
int val, int val2, long mask);
+ int (*read_avail)(struct adi_axi_adc_conv *conv,
+ struct iio_chan_spec const *chan,
+ const int **val, int *type, int *length, long mask);
};

struct adi_axi_adc_conv *devm_adi_axi_adc_conv_register(struct device *dev,

--
2.42.1