iio: pressure: mprls0025pa remove defaults

This driver supports 32*3 combinations of fixed ranges and transfer
functions, plus custom ranges.

So statistically a user has more than 99% chance that the provided
default configuration will generate invalid pressure readings if the
bindings are not initialized and the driver is instantiated via sysfs.

The current patch removes this loophole making sure the driver loads
only if the firmware properties are present.
Co-developed-by: Andreas Klinger <ak@it-klinger.de>
Signed-off-by: Andreas Klinger <ak@it-klinger.de>
Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Link: https://lore.kernel.org/r/20231229092445.30180-7-petre.rodan@subdimension.roSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/pressure/mprls0025pa.c

@@ -353,34 +353,26 @@ static int mpr_probe(struct i2c_client *client)
 		return dev_err_probe(dev, ret,
 				"can't get and enable vdd supply\n");
 
-	if (dev_fwnode(dev)) {
-		ret = device_property_read_u32(dev, "honeywell,pmin-pascal",
-								&data->pmin);
-		if (ret)
-			return dev_err_probe(dev, ret,
-				"honeywell,pmin-pascal could not be read\n");
-		ret = device_property_read_u32(dev, "honeywell,pmax-pascal",
-								&data->pmax);
-		if (ret)
-			return dev_err_probe(dev, ret,
-				"honeywell,pmax-pascal could not be read\n");
-		ret = device_property_read_u32(dev,
-				"honeywell,transfer-function", &func);
-		if (ret)
-			return dev_err_probe(dev, ret,
-				"honeywell,transfer-function could not be read\n");
-		data->function = func - 1;
-		if (data->function > MPR_FUNCTION_C)
-			return dev_err_probe(dev, -EINVAL,
-				"honeywell,transfer-function %d invalid\n",
-								data->function);
-	} else {
-		/* when loaded as i2c device we need to use default values */
-		dev_notice(dev, "firmware node not found; using defaults\n");
-		data->pmin = 0;
-		data->pmax = 172369; /* 25 psi */
-		data->function = MPR_FUNCTION_A;
-	}
+	ret = device_property_read_u32(dev, "honeywell,pmin-pascal",
+				       &data->pmin);
+	if (ret)
+		return dev_err_probe(dev, ret,
+				   "honeywell,pmin-pascal could not be read\n");
+	ret = device_property_read_u32(dev, "honeywell,pmax-pascal",
+				       &data->pmax);
+	if (ret)
+		return dev_err_probe(dev, ret,
+				   "honeywell,pmax-pascal could not be read\n");
+	ret = device_property_read_u32(dev,
+				       "honeywell,transfer-function", &func);
+	if (ret)
+		return dev_err_probe(dev, ret,
+			     "honeywell,transfer-function could not be read\n");
+	data->function = func - 1;
+	if (data->function > MPR_FUNCTION_C)
+		return dev_err_probe(dev, -EINVAL,
+				     "honeywell,transfer-function %d invalid\n",
+				     data->function);
 
 	data->outmin = mpr_func_spec[data->function].output_min;
 	data->outmax = mpr_func_spec[data->function].output_max;