[PATCH 14/14] HID: wiimote: Read wiimote battery charge level

@@ -8,3 +8,11 @@ Contact:	David Herrmann <dh.herrmann@googlemail.com>
 Description:	Make it possible to set/get current led state. Reading from it
 		returns 0 if led is off and 1 if it is on. Writing 0 to it
 		disables the led, writing 1 enables it.
+
+What:		/sys/bus/hid/drivers/wiimote/<dev>/battery
+Date:		July 2011
+KernelVersion:	3.2
+Contact:	David Herrmann <dh.herrmann@googlemail.com>
+Description:	Readonly attribute which returns the current battery charge
+		level. An integer between 0 and 255 is returned, 0 means empty
+		and 255 full.

@@ -20,7 +20,7 @@
 #include <linux/spinlock.h>
 #include "hid-ids.h"
 
-#define WIIMOTE_VERSION "0.1"
+#define WIIMOTE_VERSION "0.2"
 #define WIIMOTE_NAME "Nintendo Wii Remote"
 #define WIIMOTE_BUFSIZE 32
 

@@ -133,6 +133,9 @@ static __u16 wiiproto_keymap[] = {
 	BTN_MODE,	/* WIIPROTO_KEY_HOME */
 };
 
+#define dev_to_wii(pdev) hid_get_drvdata(container_of(pdev, struct hid_device, \
+									dev))
+
 /* requires the state.lock spinlock to be held */
 static inline bool wiimote_cmd_pending(struct wiimote_data *wdata, int cmd,
 								__u32 opt)

@@ -638,6 +641,34 @@ static int wiimote_ff_play(struct input_dev *dev, void *data,
 	return 0;
 }
 
+static ssize_t wiifs_battery_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct wiimote_data *wdata = dev_to_wii(dev);
+	unsigned long flags;
+	int state, ret;
+
+	ret = wiimote_cmd_acquire(wdata);
+	if (ret)
+		return ret;
+
+	spin_lock_irqsave(&wdata->state.lock, flags);
+	wiimote_cmd_set(wdata, WIIPROTO_REQ_SREQ, 0);
+	wiiproto_req_status(wdata);
+	spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+	ret = wiimote_cmd_wait(wdata);
+	state = wdata->state.cmd_battery;
+	wiimote_cmd_release(wdata);
+
+	if (ret)
+		return ret;
+
+	return sprintf(buf, "%d\n", state);
+}
+
+static DEVICE_ATTR(battery, S_IRUGO, wiifs_battery_show, NULL);
+
 static int wiimote_input_open(struct input_dev *dev)
 {
 	struct wiimote_data *wdata = input_get_drvdata(dev);

@@ -1154,6 +1185,7 @@ err:
 static void wiimote_destroy(struct wiimote_data *wdata)
 {
 	wiimote_leds_destroy(wdata);
+	device_remove_file(&wdata->hdev->dev, &dev_attr_battery);
 
 	input_unregister_device(wdata->accel);
 	input_unregister_device(wdata->ir);

@@ -1206,6 +1238,10 @@ static int wiimote_hid_probe(struct hid_device *hdev,
 		goto err_input;
 	}
 
+	ret = device_create_file(&hdev->dev, &dev_attr_battery);
+	if (ret)
+		goto err_free;
+
 	ret = wiimote_leds_create(wdata);
 	if (ret)
 		goto err_free;