leds: aw200xx: Calculate dts property display_rows in the driver

Get rid of device tree property "awinic,display-rows". The property
value actually means number of current switches and depends on how LEDs
are connected to the device. It should be calculated manually by max
used LED number. In the same way it is computed automatically now.
Max used LED is taken from LED definition subnodes.

Signed-off-by: George Stark <gnstark@salutedevices.com>
Signed-off-by: Dmitry Rokosov <ddrokosov@salutedevices.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20231125200519.1750-5-ddrokosov@salutedevices.com
Signed-off-by: Lee Jones <lee@kernel.org>

Author: geo-stark

drivers/leds/leds-aw200xx.c

@@ -379,25 +379,42 @@ static void aw200xx_disable(const struct aw200xx *const chip)
 	return gpiod_set_value_cansleep(chip->hwen, 0);
 }
 
+static int aw200xx_probe_get_display_rows(struct device *dev,
+					  struct aw200xx *chip)
+{
+	struct fwnode_handle *child;
+	u32 max_source = 0;
+
+	device_for_each_child_node(dev, child) {
+		u32 source;
+		int ret;
+
+		ret = fwnode_property_read_u32(child, "reg", &source);
+		if (ret || source >= chip->cdef->channels)
+			continue;
+
+		max_source = max(max_source, source);
+	}
+
+	if (max_source == 0)
+		return -EINVAL;
+
+	chip->display_rows = max_source / chip->cdef->display_size_columns + 1;
+
+	return 0;
+}
+
 static int aw200xx_probe_fw(struct device *dev, struct aw200xx *chip)
 {
 	struct fwnode_handle *child;
 	u32 current_min, current_max, min_uA;
 	int ret;
 	int i;
 
-	ret = device_property_read_u32(dev, "awinic,display-rows",
-				       &chip->display_rows);
+	ret = aw200xx_probe_get_display_rows(dev, chip);
 	if (ret)
 		return dev_err_probe(dev, ret,
-				     "Failed to read 'display-rows' property\n");
-
-	if (!chip->display_rows ||
-	    chip->display_rows > chip->cdef->display_size_rows_max) {
-		return dev_err_probe(dev, -EINVAL,
-				     "Invalid leds display size %u\n",
-				     chip->display_rows);
-	}
+				     "No valid led definitions found\n");
 
 	current_max = aw200xx_imax_from_global(chip, AW200XX_IMAX_MAX_uA);
 	current_min = aw200xx_imax_from_global(chip, AW200XX_IMAX_MIN_uA);