abx500-chargalg: Add new sysfs interface to get current charge status

Allow a user to check on AB8500 charging status from debugfs.
Signed-off-by: NLee Jones <lee.jones@linaro.org>

drivers/power/ab8500_charger.c

@@ -2764,6 +2764,9 @@ static int ab8500_charger_usb_notifier_call(struct notifier_block *nb,
 	enum ab8500_usb_state bm_usb_state;
 	unsigned mA = *((unsigned *)power);
 
+	if (!di)
+		return NOTIFY_DONE;
+
 	if (event != USB_EVENT_VBUS) {
 		dev_dbg(di->dev, "not a standard host, returning\n");
 		return NOTIFY_DONE;

drivers/power/abx500_chargalg.c

@@ -1653,6 +1653,25 @@ static int abx500_chargalg_get_property(struct power_supply *psy,
 
 /* Exposure to the sysfs interface */
 
+/**
+ * abx500_chargalg_sysfs_show() - sysfs show operations
+ * @kobj:      pointer to the struct kobject
+ * @attr:      pointer to the struct attribute
+ * @buf:       buffer that holds the parameter to send to userspace
+ *
+ * Returns a buffer to be displayed in user space
+ */
+static ssize_t abx500_chargalg_sysfs_show(struct kobject *kobj,
+					  struct attribute *attr, char *buf)
+{
+	struct abx500_chargalg *di = container_of(kobj,
+               struct abx500_chargalg, chargalg_kobject);
+
+	return sprintf(buf, "%d\n",
+		       di->susp_status.ac_suspended &&
+		       di->susp_status.usb_suspended);
+}
+
 /**
  * abx500_chargalg_sysfs_charger() - sysfs store operations
  * @kobj:      pointer to the struct kobject
@@ -1721,7 +1740,7 @@ static ssize_t abx500_chargalg_sysfs_charger(struct kobject *kobj,
 static struct attribute abx500_chargalg_en_charger = \
 {
 	.name = "chargalg",
-	.mode = S_IWUSR,
+	.mode = S_IRUGO | S_IWUSR,
 };
 
 static struct attribute *abx500_chargalg_chg[] = {
@@ -1730,6 +1749,7 @@ static struct attribute *abx500_chargalg_chg[] = {
 };
 
 static const struct sysfs_ops abx500_chargalg_sysfs_ops = {
+	.show = abx500_chargalg_sysfs_show,
 	.store = abx500_chargalg_sysfs_charger,
 };