[PATCH 2/2 v2] HID: leds: Use attribute-groups in MSI GT683R driver

[Janne Kanniainen <janne.kanniainen@gmail.com>]

Use attribute-groups to fix race condition.

Signed-off-by: Janne Kanniainen <janne.kanniainen@gmail.com>
---
 .../ABI/testing/sysfs-class-hid-driver-gt683r      |  6 +++--
 drivers/hid/hid-gt683r.c                           | 31 +++++++++++++---------
 2 files changed, 22 insertions(+), 15 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-class-hid-driver-gt683r b/Documentation/ABI/testing/sysfs-class-hid-driver-gt683r
index 317e9d5..c97970a 100644
--- a/Documentation/ABI/testing/sysfs-class-hid-driver-gt683r
+++ b/Documentation/ABI/testing/sysfs-class-hid-driver-gt683r
@@ -1,9 +1,11 @@
-What:		/sys/class/hidraw/<hidraw>/device/leds_mode
+What:		/sys/class/leds/<led>/msi_mode
 Date:		Jun 2014
 KernelVersion:	3.17
 Contact:	Janne Kanniainen <janne.kanniainen@gmail.com>
 Description:
-		Set the mode of LEDs
+		Set the mode of LEDs. You should notice that changing the mode
+		of one LED will update the mode of its two sibling devices as
+		well
 
 		0 - normal
 		1 - audio
diff --git a/drivers/hid/hid-gt683r.c b/drivers/hid/hid-gt683r.c
index 073bd80..aba6636 100644
--- a/drivers/hid/hid-gt683r.c
+++ b/drivers/hid/hid-gt683r.c
@@ -84,12 +84,13 @@ static void gt683r_brightness_set(struct led_classdev *led_cdev,
 	}
 }
 
-static ssize_t leds_mode_show(struct device *dev,
+static ssize_t msi_mode_show(struct device *led_dev,
 				struct device_attribute *attr,
 				char *buf)
 {
 	u8 sysfs_mode;
-	struct hid_device *hdev = container_of(dev, struct hid_device, dev);
+	struct hid_device *hdev = container_of(led_dev->parent,
+					struct hid_device, dev);
 	struct gt683r_led *led = hid_get_drvdata(hdev);
 
 	if (led->mode == GT683R_LED_NORMAL)
@@ -102,15 +103,15 @@ static ssize_t leds_mode_show(struct device *dev,
 	return scnprintf(buf, PAGE_SIZE, "%u\n", sysfs_mode);
 }
 
-static ssize_t leds_mode_store(struct device *dev,
+static ssize_t msi_mode_store(struct device *led_dev,
 				struct device_attribute *attr,
 				const char *buf, size_t count)
 {
 	u8 sysfs_mode;
-	struct hid_device *hdev = container_of(dev, struct hid_device, dev);
+	struct hid_device *hdev = container_of(led_dev->parent,
+					struct hid_device, dev);
 	struct gt683r_led *led = hid_get_drvdata(hdev);
 
-
 	if (kstrtou8(buf, 10, &sysfs_mode) || sysfs_mode > 2)
 		return -EINVAL;
 
@@ -212,7 +213,14 @@ fail:
 	mutex_unlock(&led->lock);
 }
 
-static DEVICE_ATTR_RW(leds_mode);
+static DEVICE_ATTR_RW(msi_mode);
+
+static struct attribute *gt683r_led_attrs[] = {
+	&dev_attr_msi_mode.attr,
+	NULL
+};
+
+ATTRIBUTE_GROUPS(gt683r_led);
 
 static int gt683r_led_probe(struct hid_device *hdev,
 			const struct hid_device_id *id)
@@ -261,6 +269,8 @@ static int gt683r_led_probe(struct hid_device *hdev,
 		led->led_devs[i].name = name;
 		led->led_devs[i].max_brightness = 1;
 		led->led_devs[i].brightness_set = gt683r_brightness_set;
+		led->led_devs[i].groups = gt683r_led_groups;
+
 		ret = led_classdev_register(&hdev->dev, &led->led_devs[i]);
 		if (ret) {
 			hid_err(hdev, "could not register led device\n");
@@ -268,17 +278,12 @@ static int gt683r_led_probe(struct hid_device *hdev,
 		}
 	}
 
-	ret = device_create_file(&led->hdev->dev, &dev_attr_leds_mode);
-	if (ret) {
-		hid_err(hdev, "could not make mode attribute file\n");
-		goto fail;
-	}
-
 	return 0;
 
 fail:
 	for (i = i - 1; i >= 0; i--)
 		led_classdev_unregister(&led->led_devs[i]);
+
 	hid_hw_stop(hdev);
 	return ret;
 }
@@ -288,9 +293,9 @@ static void gt683r_led_remove(struct hid_device *hdev)
 	int i;
 	struct gt683r_led *led = hid_get_drvdata(hdev);
 
-	device_remove_file(&hdev->dev, &dev_attr_leds_mode);
 	for (i = 0; i < GT683R_LED_COUNT; i++)
 		led_classdev_unregister(&led->led_devs[i]);
+
 	flush_work(&led->work);
 	hid_hw_stop(hdev);
 }
-- 
1.9.2