iio: adc: xilinx-xadc: Make use of device properties

Convert the module to be property provider agnostic and allow
it to be used on non-OF platforms.

Add mod_devicetable.h include.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/20220531141118.64540-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/adc/xilinx-xadc-core.c

@@ -17,10 +17,11 @@
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
 #include <linux/module.h>
-#include <linux/of.h>
 #include <linux/overflow.h>
 #include <linux/platform_device.h>
+#include <linux/property.h>
 #include <linux/slab.h>
 #include <linux/sysfs.h>
 
@@ -1182,14 +1183,13 @@ static const struct of_device_id xadc_of_match_table[] = {
 };
 MODULE_DEVICE_TABLE(of, xadc_of_match_table);
 
-static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
-	unsigned int *conf, int irq)
+static int xadc_parse_dt(struct iio_dev *indio_dev, unsigned int *conf, int irq)
 {
 	struct device *dev = indio_dev->dev.parent;
 	struct xadc *xadc = iio_priv(indio_dev);
 	const struct iio_chan_spec *channel_templates;
 	struct iio_chan_spec *channels, *chan;
-	struct device_node *chan_node, *child;
+	struct fwnode_handle *chan_node, *child;
 	unsigned int max_channels;
 	unsigned int num_channels;
 	const char *external_mux;
@@ -1200,7 +1200,7 @@ static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
 
 	*conf = 0;
 
-	ret = of_property_read_string(np, "xlnx,external-mux", &external_mux);
+	ret = device_property_read_string(dev, "xlnx,external-mux", &external_mux);
 	if (ret < 0 || strcasecmp(external_mux, "none") == 0)
 		xadc->external_mux_mode = XADC_EXTERNAL_MUX_NONE;
 	else if (strcasecmp(external_mux, "single") == 0)
@@ -1211,8 +1211,7 @@ static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
 		return -EINVAL;
 
 	if (xadc->external_mux_mode != XADC_EXTERNAL_MUX_NONE) {
-		ret = of_property_read_u32(np, "xlnx,external-mux-channel",
-					&ext_mux_chan);
+		ret = device_property_read_u32(dev, "xlnx,external-mux-channel", &ext_mux_chan);
 		if (ret < 0)
 			return ret;
 
@@ -1247,19 +1246,19 @@ static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
 	num_channels = 9;
 	chan = &channels[9];
 
-	chan_node = of_get_child_by_name(np, "xlnx,channels");
+	chan_node = device_get_named_child_node(dev, "xlnx,channels");
 	if (chan_node) {
-		for_each_child_of_node(chan_node, child) {
+		fwnode_for_each_child_node(chan_node, child) {
 			if (num_channels >= max_channels) {
-				of_node_put(child);
+				fwnode_handle_put(child);
 				break;
 			}
 
-			ret = of_property_read_u32(child, "reg", &reg);
+			ret = fwnode_property_read_u32(child, "reg", &reg);
 			if (ret || reg > 16)
 				continue;
 
-			if (of_property_read_bool(child, "xlnx,bipolar"))
+			if (fwnode_property_read_bool(child, "xlnx,bipolar"))
 				chan->scan_type.sign = 's';
 
 			if (reg == 0) {
@@ -1273,7 +1272,7 @@ static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
 			chan++;
 		}
 	}
-	of_node_put(chan_node);
+	fwnode_handle_put(chan_node);
 
 	/* No IRQ => no events */
 	if (irq <= 0) {
@@ -1316,7 +1315,6 @@ static void xadc_cancel_delayed_work(void *data)
 static int xadc_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
-	const struct of_device_id *id;
 	const struct xadc_ops *ops;
 	struct iio_dev *indio_dev;
 	unsigned int bipolar_mask;
@@ -1326,15 +1324,10 @@ static int xadc_probe(struct platform_device *pdev)
 	int irq;
 	int i;
 
-	if (!dev->of_node)
-		return -ENODEV;
-
-	id = of_match_node(xadc_of_match_table, dev->of_node);
-	if (!id)
+	ops = device_get_match_data(dev);
+	if (!ops)
 		return -EINVAL;
 
-	ops = id->data;
-
 	irq = platform_get_irq_optional(pdev, 0);
 	if (irq < 0 &&
 	    (irq != -ENXIO || !(ops->flags & XADC_FLAGS_IRQ_OPTIONAL)))
@@ -1345,7 +1338,7 @@ static int xadc_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	xadc = iio_priv(indio_dev);
-	xadc->ops = id->data;
+	xadc->ops = ops;
 	init_completion(&xadc->completion);
 	mutex_init(&xadc->mutex);
 	spin_lock_init(&xadc->lock);
@@ -1359,7 +1352,7 @@ static int xadc_probe(struct platform_device *pdev)
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &xadc_info;
 
-	ret = xadc_parse_dt(indio_dev, dev->of_node, &conf0, irq);
+	ret = xadc_parse_dt(indio_dev, &conf0, irq);
 	if (ret)
 		return ret;