[PATCH v3 3/3] Bluetooth: Allow reset via sysfs

[Hsin-chen Chuang]

From: Hsin-chen Chuang <chharry@xxxxxxxxxxxx>

Allow sysfs to trigger hdev reset. This is required to recover devices
that are not responsive from userspace.

Signed-off-by: Hsin-chen Chuang <chharry@xxxxxxxxxxxx>
---
This commit has been tested on a Chromebook by running
`echo 1 > /sys/class/bluetooth/hci0/reset`

(no changes since v2)

Changes in v2:
- Splitted out the btusb change

 net/bluetooth/hci_sysfs.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/net/bluetooth/hci_sysfs.c b/net/bluetooth/hci_sysfs.c
index 4b54dbbf0729..041ce9adc378 100644
--- a/net/bluetooth/hci_sysfs.c
+++ b/net/bluetooth/hci_sysfs.c
@@ -90,9 +90,28 @@ static void bt_host_release(struct device *dev)
 	module_put(THIS_MODULE);
 }
 
+static ssize_t reset_store(struct device *dev, struct device_attribute *attr,
+			   const char *buf, size_t count)
+{
+	struct hci_dev *hdev = to_hci_dev(dev);
+
+	if (hdev->reset)
+		hdev->reset(hdev);
+
+	return count;
+}
+static DEVICE_ATTR_WO(reset);
+
+static struct attribute *bt_host_attrs[] = {
+	&dev_attr_reset.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(bt_host);
+
 static const struct device_type bt_host = {
 	.name    = "host",
 	.release = bt_host_release,
+	.groups = bt_host_groups,
 };
 
 void hci_init_sysfs(struct hci_dev *hdev)
-- 
2.47.1.613.gc27f4b7a9f-goog