HID: wiimote: Add extension sysfs attribute

Add new sysfs attribute "extension" which returns the currently connected and
initialized extensions.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 46 insertions, 0 deletions

diff --git a/drivers/hid/hid-wiimote-ext.c b/drivers/hid/hid-wiimote-ext.c
index 233bdfe3205b..477513dfeb7a 100644
--- a/drivers/hid/hid-wiimote-ext.c
+++ b/drivers/hid/hid-wiimote-ext.c
@@ -199,11 +199,47 @@ bool wiiext_active(struct wiimote_data *wdata)
         return wdata->ext->motionp || wdata->ext->ext_type;
 }
 
+static ssize_t wiiext_show(struct device *dev, struct device_attribute *attr,
+                                                                char *buf)
+{
+        struct wiimote_data *wdata = dev_to_wii(dev);
+        __u8 type = WIIEXT_NONE;
+        bool motionp = false;
+        unsigned long flags;
+
+        spin_lock_irqsave(&wdata->state.lock, flags);
+        if (wdata->ext) {
+                motionp = wdata->ext->motionp;
+                type = wdata->ext->ext_type;
+        }
+        spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+        if (type == WIIEXT_NUNCHUCK) {
+                if (motionp)
+                        return sprintf(buf, "motionp+nunchuck\n");
+                else
+                        return sprintf(buf, "nunchuck\n");
+        } else if (type == WIIEXT_CLASSIC) {
+                if (motionp)
+                        return sprintf(buf, "motionp+classic\n");
+                else
+                        return sprintf(buf, "classic\n");
+        } else {
+                if (motionp)
+                        return sprintf(buf, "motionp\n");
+                else
+                        return sprintf(buf, "none\n");
+        }
+}
+
+static DEVICE_ATTR(extension, S_IRUGO, wiiext_show, NULL);
+
 /* Initializes the extension driver of a wiimote */
 int wiiext_init(struct wiimote_data *wdata)
 {
         struct wiimote_ext *ext;
         unsigned long flags;
+        int ret;
 
         ext = kzalloc(sizeof(*ext), GFP_KERNEL);
         if (!ext)
@@ -212,11 +248,19 @@ int wiiext_init(struct wiimote_data *wdata)
         ext->wdata = wdata;
         INIT_WORK(&ext->worker, wiiext_worker);
 
+        ret = device_create_file(&wdata->hdev->dev, &dev_attr_extension);
+        if (ret)
+                goto err;
+
         spin_lock_irqsave(&wdata->state.lock, flags);
         wdata->ext = ext;
         spin_unlock_irqrestore(&wdata->state.lock, flags);
 
         return 0;
+
+err:
+        kfree(ext);
+        return ret;
 }
 
 /* Deinitializes the extension driver of a wiimote */
@@ -240,6 +284,8 @@ void wiiext_deinit(struct wiimote_data *wdata)
         wdata->ext = NULL;
         spin_unlock_irqrestore(&wdata->state.lock, flags);
 
+        device_remove_file(&wdata->hdev->dev, &dev_attr_extension);
+
         cancel_work_sync(&ext->worker);
         kfree(ext);
 }