HID: i2c-hid: Add vddl regulator control

Some wacom w9013 devices have a vddl supply for "low valtage"
requirements. Add support in this driver to turn on this low voltage
supply. We can also drop a handful of error messages because the
regulator core is already printing an error when bulk regulators fail to
enable or disable.

Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Dmitry Torokhov <dtor@chromium.org>
Cc: Doug Anderson <dianders@chromium.org>
Acked-by: Rob Herring <robh@kernel.org>
Cc: <devicetree@vger.kernel.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Documentation/devicetree/bindings/input/hid-over-i2c.txt

@@ -26,7 +26,8 @@ device-specific compatible properties, which should be used in addition to the
 
 - compatible:
   * "wacom,w9013" (Wacom W9013 digitizer). Supports:
-    - vdd-supply
+    - vdd-supply (3.3V)
+    - vddl-supply (1.8V)
     - post-power-on-delay-ms
 
 - vdd-supply: phandle of the regulator that provides the supply voltage.

drivers/hid/i2c-hid/i2c-hid.c

@@ -1021,21 +1021,20 @@ static int i2c_hid_probe(struct i2c_client *client,
 	/* Parse platform agnostic common properties from ACPI / device tree */
 	i2c_hid_fwnode_probe(client, &ihid->pdata);
 
-	ihid->pdata.supply = devm_regulator_get(&client->dev, "vdd");
-	if (IS_ERR(ihid->pdata.supply)) {
-		ret = PTR_ERR(ihid->pdata.supply);
-		if (ret != -EPROBE_DEFER)
-			dev_err(&client->dev, "Failed to get regulator: %d\n",
-				ret);
-		goto err;
-	}
+	ihid->pdata.supplies[0].supply = "vdd";
+	ihid->pdata.supplies[1].supply = "vddl";
+
+	ret = devm_regulator_bulk_get(&client->dev,
+				      ARRAY_SIZE(ihid->pdata.supplies),
+				      ihid->pdata.supplies);
+	if (ret)
+		return ret;
+
+	ret = regulator_bulk_enable(ARRAY_SIZE(ihid->pdata.supplies),
+				    ihid->pdata.supplies);
+	if (ret < 0)
+		return ret;
 
-	ret = regulator_enable(ihid->pdata.supply);
-	if (ret < 0) {
-		dev_err(&client->dev, "Failed to enable regulator: %d\n",
-			ret);
-		goto err;
-	}
 	if (ihid->pdata.post_power_delay_ms)
 		msleep(ihid->pdata.post_power_delay_ms);
 
@@ -1122,9 +1121,8 @@ err_pm:
 	pm_runtime_disable(&client->dev);
 
 err_regulator:
-	regulator_disable(ihid->pdata.supply);
-
-err:
+	regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
+			       ihid->pdata.supplies);
 	i2c_hid_free_buffers(ihid);
 	return ret;
 }
@@ -1147,7 +1145,8 @@ static int i2c_hid_remove(struct i2c_client *client)
 	if (ihid->bufsize)
 		i2c_hid_free_buffers(ihid);
 
-	regulator_disable(ihid->pdata.supply);
+	regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
+			       ihid->pdata.supplies);
 
 	return 0;
 }
@@ -1198,9 +1197,8 @@ static int i2c_hid_suspend(struct device *dev)
 			hid_warn(hid, "Failed to enable irq wake: %d\n",
 				wake_status);
 	} else {
-		ret = regulator_disable(ihid->pdata.supply);
-		if (ret < 0)
-			hid_warn(hid, "Failed to disable supply: %d\n", ret);
+		regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
+				       ihid->pdata.supplies);
 	}
 
 	return 0;
@@ -1215,9 +1213,11 @@ static int i2c_hid_resume(struct device *dev)
 	int wake_status;
 
 	if (!device_may_wakeup(&client->dev)) {
-		ret = regulator_enable(ihid->pdata.supply);
-		if (ret < 0)
-			hid_warn(hid, "Failed to enable supply: %d\n", ret);
+		ret = regulator_bulk_enable(ARRAY_SIZE(ihid->pdata.supplies),
+					    ihid->pdata.supplies);
+		if (ret)
+			hid_warn(hid, "Failed to enable supplies: %d\n", ret);
+
 		if (ihid->pdata.post_power_delay_ms)
 			msleep(ihid->pdata.post_power_delay_ms);
 	} else if (ihid->irq_wake_enabled) {

include/linux/platform_data/i2c-hid.h

@@ -12,14 +12,13 @@
 #ifndef __LINUX_I2C_HID_H
 #define __LINUX_I2C_HID_H
 
+#include <linux/regulator/consumer.h>
 #include <linux/types.h>
 
-struct regulator;
-
 /**
  * struct i2chid_platform_data - used by hid over i2c implementation.
  * @hid_descriptor_address: i2c register where the HID descriptor is stored.
- * @supply: regulator for powering on the device.
+ * @supplies: regulators for powering on the device.
  * @post_power_delay_ms: delay after powering on before device is usable.
  *
  * Note that it is the responsibility of the platform driver (or the acpi 5.0
@@ -35,7 +34,7 @@ struct regulator;
  */
 struct i2c_hid_platform_data {
 	u16 hid_descriptor_address;
-	struct regulator *supply;
+	struct regulator_bulk_data supplies[2];
 	int post_power_delay_ms;
 };