Input: ad7879 - return plain error code from ad7879_probe()

With the switch to devm, there is no need for ad7879_probe() to return the
touchscreen structure, we can use plain error code. This also fixes issue
introduced with devm concersion, where we returned 0 on success (which
worked OK since IS_ERR(0) would not trigger, but was not correct
regardless).

Fixes: 381f688eee3d ("Input: ad7879 - use more devm interfaces")
Acked-by: Michael Hennerich <[e-mail]>
Signed-off-by: Dmitry Torokhov <[e-mail]>

drivers/input/touchscreen/ad7879-i2c.c

···
 static int ad7879_i2c_probe(struct i2c_client *client,
 				      const struct i2c_device_id *id)
 {
-	struct ad7879 *ts;
 	struct regmap *regmap;
 
 	if (!i2c_check_functionality(client->adapter,
···
 	if (IS_ERR(regmap))
 		return PTR_ERR(regmap);
 
-	ts = ad7879_probe(&client->dev, regmap, client->irq,
-			  BUS_I2C, AD7879_DEVID);
-	if (IS_ERR(ts))
-		return PTR_ERR(ts);
-
-	return 0;
+	return ad7879_probe(&client->dev, regmap, client->irq,
+			    BUS_I2C, AD7879_DEVID);
 }
 
 static const struct i2c_device_id ad7879_id[] = {

drivers/input/touchscreen/ad7879-spi.c

···
 
 static int ad7879_spi_probe(struct spi_device *spi)
 {
-	struct ad7879 *ts;
 	struct regmap *regmap;
 
 	/* don't exceed max specified SPI CLK frequency */
···
 	if (IS_ERR(regmap))
 		return PTR_ERR(regmap);
 
-	ts = ad7879_probe(&spi->dev, regmap, spi->irq, BUS_SPI, AD7879_DEVID);
-	if (IS_ERR(ts))
-		return PTR_ERR(ts);
-
-	return 0;
+	return ad7879_probe(&spi->dev, regmap, spi->irq, BUS_SPI, AD7879_DEVID);
 }
 
 #ifdef CONFIG_OF

drivers/input/touchscreen/ad7879.c

···
 	sysfs_remove_group(&ts->dev->kobj, &ad7879_attr_group);
 }
 
-struct ad7879 *ad7879_probe(struct device *dev, struct regmap *regmap,
-			    int irq, u16 bustype, u8 devid)
+int ad7879_probe(struct device *dev, struct regmap *regmap,
+		 int irq, u16 bustype, u8 devid)
 {
 	struct ad7879_platform_data *pdata = dev_get_platdata(dev);
 	struct ad7879 *ts;
···
 
 	if (irq <= 0) {
 		dev_err(dev, "No IRQ specified\n");
-		return ERR_PTR(-EINVAL);
+		return -EINVAL;
 	}
 
 	ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
 	if (!ts)
-		return ERR_PTR(-ENOMEM);
+		return -ENOMEM;
 
 	if (pdata) {
 		/* Platform data use swapped axis (backward compatibility) */
···
 		ad7879_parse_dt(dev, ts);
 	} else {
 		dev_err(dev, "No platform data\n");
-		return ERR_PTR(-EINVAL);
+		return -EINVAL;
 	}
 
 	input_dev = devm_input_allocate_device(dev);
 	if (!input_dev) {
 		dev_err(dev, "Failed to allocate input device\n");
-		return ERR_PTR(-ENOMEM);
+		return -ENOMEM;
 	}
 
 	ts->dev = dev;
···
 		touchscreen_parse_properties(input_dev, false, NULL);
 		if (!input_abs_get_max(input_dev, ABS_PRESSURE)) {
 			dev_err(dev, "Touchscreen pressure is not specified\n");
-			return ERR_PTR(-EINVAL);
+			return -EINVAL;
 		}
 	}
 
 	err = ad7879_write(ts, AD7879_REG_CTRL2, AD7879_RESET);
 	if (err < 0) {
 		dev_err(dev, "Failed to write %s\n", input_dev->name);
-		return ERR_PTR(err);
+		return err;
 	}
 
 	revid = ad7879_read(ts, AD7879_REG_REVID);
···
 	if (input_dev->id.product != devid) {
 		dev_err(dev, "Failed to probe %s (%x vs %x)\n",
 			input_dev->name, devid, revid);
-		return ERR_PTR(-ENODEV);
+		return -ENODEV;
 	}
 
 	ts->cmd_crtl3 = AD7879_YPLUS_BIT |
···
 					dev_name(dev), ts);
 	if (err) {
 		dev_err(dev, "Failed to request IRQ: %d\n", err);
-		return ERR_PTR(err);
+		return err;
 	}
 
 	__ad7879_disable(ts);
 
 	err = sysfs_create_group(&dev->kobj, &ad7879_attr_group);
 	if (err)
-		return ERR_PTR(err);
+		return err;
 
 	err = devm_add_action_or_reset(dev, ad7879_cleanup_sysfs, ts);
 	if (err)
-		return ERR_PTR(err);
+		return err;
 
 	err = ad7879_gpio_add(ts, pdata);
 	if (err)
-		return ERR_PTR(err);
+		return err;
 
 	err = input_register_device(input_dev);
 	if (err)
-		return ERR_PTR(err);
+		return err;
 
 	dev_set_drvdata(dev, ts);
 

drivers/input/touchscreen/ad7879.h

···
 
 #include <linux/types.h>
 
-struct ad7879;
 struct device;
 struct regmap;
 
 extern const struct dev_pm_ops ad7879_pm_ops;
 
-struct ad7879 *ad7879_probe(struct device *dev, struct regmap *regmap,
-			    int irq, u16 bustype, u8 devid);
+int ad7879_probe(struct device *dev, struct regmap *regmap,
+		 int irq, u16 bustype, u8 devid);
 
 #endif