iio: adc: qcom-pm8xxx-xoadc: convert to device properties

Make the conversion to firmware agnostic device properties. As part of
the conversion the IIO inkern interface 'of_xlate()' is also converted to
'fwnode_xlate()'. The goal is to completely drop 'of_xlate' and hence OF
dependencies from IIO.

Signed-off-by: Nuno Sá <[e-mail]>
Acked-by: Linus Walleij <[e-mail]>
Reviewed-by: Andy Shevchenko <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jonathan Cameron <[e-mail]>

drivers/iio/adc/qcom-pm8xxx-xoadc.c

···
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
 #include <linux/module.h>
-#include <linux/of.h>
-#include <linux/of_device.h>
+#include <linux/mod_devicetable.h>
 #include <linux/platform_device.h>
+#include <linux/property.h>
 #include <linux/regmap.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
···
 	}
 }
 
-static int pm8xxx_of_xlate(struct iio_dev *indio_dev,
-			   const struct of_phandle_args *iiospec)
+static int pm8xxx_fwnode_xlate(struct iio_dev *indio_dev,
+			       const struct fwnode_reference_args *iiospec)
 {
 	struct pm8xxx_xoadc *adc = iio_priv(indio_dev);
 	u8 pre_scale_mux;
···
 	 * First cell is prescaler or premux, second cell is analog
 	 * mux.
 	 */
-	if (iiospec->args_count != 2) {
-		dev_err(&indio_dev->dev, "wrong number of arguments for %pOFn need 2 got %d\n",
-			iiospec->np,
-			iiospec->args_count);
+	if (iiospec->nargs != 2) {
+		dev_err(&indio_dev->dev, "wrong number of arguments for %pfwP need 2 got %d\n",
+			iiospec->fwnode,
+			iiospec->nargs);
 		return -EINVAL;
 	}
 	pre_scale_mux = (u8)iiospec->args[0];
···
 }
 
 static const struct iio_info pm8xxx_xoadc_info = {
-	.of_xlate = pm8xxx_of_xlate,
+	.fwnode_xlate = pm8xxx_fwnode_xlate,
 	.read_raw = pm8xxx_read_raw,
 };
 
 static int pm8xxx_xoadc_parse_channel(struct device *dev,
-				      struct device_node *np,
+				      struct fwnode_handle *fwnode,
 				      const struct xoadc_channel *hw_channels,
 				      struct iio_chan_spec *iio_chan,
 				      struct pm8xxx_chan_info *ch)
 {
-	const char *name = np->name;
+	const char *name = fwnode_get_name(fwnode);
 	const struct xoadc_channel *hwchan;
-	u32 pre_scale_mux, amux_channel;
+	u32 pre_scale_mux, amux_channel, reg[2];
 	u32 rsv, dec;
 	int ret;
 	int chid;
 
-	ret = of_property_read_u32_index(np, "reg", 0, &pre_scale_mux);
+	ret = fwnode_property_read_u32_array(fwnode, "reg", reg,
+					     ARRAY_SIZE(reg));
 	if (ret) {
-		dev_err(dev, "invalid pre scale/mux number %s\n", name);
+		dev_err(dev, "invalid pre scale/mux or amux channel number %s\n",
+			name);
 		return ret;
 	}
-	ret = of_property_read_u32_index(np, "reg", 1, &amux_channel);
-	if (ret) {
-		dev_err(dev, "invalid amux channel number %s\n", name);
-		return ret;
-	}
+
+	pre_scale_mux = reg[0];
+	amux_channel = reg[1];
 
 	/* Find the right channel setting */
 	chid = 0;
···
 	/* Everyone seems to use default ("type 2") decimation */
 	ch->decimation = VADC_DEF_DECIMATION;
 
-	if (!of_property_read_u32(np, "qcom,ratiometric", &rsv)) {
+	if (!fwnode_property_read_u32(fwnode, "qcom,ratiometric", &rsv)) {
 		ch->calibration = VADC_CALIB_RATIOMETRIC;
 		if (rsv > XOADC_RSV_MAX) {
 			dev_err(dev, "%s too large RSV value %d\n", name, rsv);
···
 	}
 
 	/* Optional decimation, if omitted we use the default */
-	ret = of_property_read_u32(np, "qcom,decimation", &dec);
+	ret = fwnode_property_read_u32(fwnode, "qcom,decimation", &dec);
 	if (!ret) {
 		ret = qcom_vadc_decimation_from_dt(dec);
 		if (ret < 0) {
···
 	return 0;
 }
 
-static int pm8xxx_xoadc_parse_channels(struct pm8xxx_xoadc *adc,
-				       struct device_node *np)
+static int pm8xxx_xoadc_parse_channels(struct pm8xxx_xoadc *adc)
 {
-	struct device_node *child;
+	struct fwnode_handle *child;
 	struct pm8xxx_chan_info *ch;
 	int ret;
 	int i;
 
-	adc->nchans = of_get_available_child_count(np);
+	adc->nchans = device_get_child_node_count(adc->dev);
 	if (!adc->nchans) {
 		dev_err(adc->dev, "no channel children\n");
 		return -ENODEV;
···
 		return -ENOMEM;
 
 	i = 0;
-	for_each_available_child_of_node(np, child) {
+	device_for_each_child_node(adc->dev, child) {
 		ch = &adc->chans[i];
 		ret = pm8xxx_xoadc_parse_channel(adc->dev, child,
 						 adc->variant->channels,
 						 &adc->iio_chans[i],
 						 ch);
 		if (ret) {
-			of_node_put(child);
+			fwnode_handle_put(child);
 			return ret;
 		}
 		i++;
···
 	const struct xoadc_variant *variant;
 	struct pm8xxx_xoadc *adc;
 	struct iio_dev *indio_dev;
-	struct device_node *np = pdev->dev.of_node;
 	struct regmap *map;
 	struct device *dev = &pdev->dev;
 	int ret;
 
-	variant = of_device_get_match_data(dev);
+	variant = device_get_match_data(dev);
 	if (!variant)
 		return -ENODEV;
 
···
 	init_completion(&adc->complete);
 	mutex_init(&adc->lock);
 
-	ret = pm8xxx_xoadc_parse_channels(adc, np);
+	ret = pm8xxx_xoadc_parse_channels(adc);
 	if (ret)
 		return ret;