[PATCH v6 3/4] iio: adc: ad7768-1: Add channel labels.

From: Cristian Pop
Date: Mon Sep 21 2020 - 09:30:52 EST


For better identification of the channels.

Signed-off-by: Cristian Pop <cristian.pop@xxxxxxxxxx>
---
Changes in v6:
- Use static variable for labels
drivers/iio/adc/ad7768-1.c | 41 ++++++++++++++++++++++++++++++++++++++
1 file changed, 41 insertions(+)

diff --git a/drivers/iio/adc/ad7768-1.c b/drivers/iio/adc/ad7768-1.c
index 0e93b0766eb4..5c0cbee03230 100644
--- a/drivers/iio/adc/ad7768-1.c
+++ b/drivers/iio/adc/ad7768-1.c
@@ -161,6 +161,7 @@ struct ad7768_state {
struct completion completion;
struct iio_trigger *trig;
struct gpio_desc *gpio_sync_in;
+ const char *labels[ARRAY_SIZE(ad7768_channels)];
/*
* DMA (thus cache coherency maintenance) requires the
* transfer buffers to live in their own cache lines.
@@ -407,6 +408,14 @@ static int ad7768_write_raw(struct iio_dev *indio_dev,
}
}

+static int ad7768_read_label(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan, char *label)
+{
+ struct ad7768_state *st = iio_priv(indio_dev);
+
+ return sprintf(label, "%s\n", st->labels[chan->channel]);
+}
+
static struct attribute *ad7768_attributes[] = {
&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
NULL
@@ -420,6 +429,7 @@ static const struct iio_info ad7768_info = {
.attrs = &ad7768_group,
.read_raw = &ad7768_read_raw,
.write_raw = &ad7768_write_raw,
+ .read_label = ad7768_read_label,
.debugfs_reg_access = &ad7768_reg_access,
};

@@ -532,6 +542,33 @@ static void ad7768_clk_disable(void *data)
clk_disable_unprepare(st->mclk);
}

+static int ad7768_set_channel_label(struct iio_dev *indio_dev,
+ int num_channels)
+{
+ struct ad7768_state *st = iio_priv(indio_dev);
+ struct device *device = indio_dev->dev.parent;
+ struct fwnode_handle *fwnode;
+ struct fwnode_handle *child;
+ const char *label;
+ int crt_ch = 0;
+
+ fwnode = dev_fwnode(device);
+ fwnode_for_each_child_node(fwnode, child) {
+ if (fwnode_property_read_u32(child, "reg", &crt_ch))
+ continue;
+
+ if (crt_ch >= num_channels)
+ continue;
+
+ if (fwnode_property_read_string(child, "label", &label))
+ continue;
+
+ st->labels[crt_ch] = label;
+ }
+
+ return 0;
+}
+
static int ad7768_probe(struct spi_device *spi)
{
struct ad7768_state *st;
@@ -604,6 +641,10 @@ static int ad7768_probe(struct spi_device *spi)

init_completion(&st->completion);

+ ret = ad7768_set_channel_label(indio_dev, ARRAY_SIZE(ad7768_channels));
+ if (ret)
+ return ret;
+
ret = devm_request_irq(&spi->dev, spi->irq,
&ad7768_interrupt,
IRQF_TRIGGER_RISING | IRQF_ONESHOT,
--
2.17.1