@@ -13,6 +13,7 @@
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/slab.h>
+#include <linux/usb/charger.h>
#include <linux/mfd/wm831x/core.h>
#include <linux/mfd/wm831x/auxadc.h>
@@ -31,6 +32,8 @@ struct wm831x_power {
char usb_name[20];
char battery_name[20];
bool have_battery;
+ struct usb_charger *usb_charger;
+ struct notifier_block usb_notify;
};
static int wm831x_power_check_online(struct wm831x *wm831x, int supply,
@@ -125,6 +128,43 @@ static enum power_supply_property wm831x_usb_props[] = {
POWER_SUPPLY_PROP_VOLTAGE_NOW,
};
+/* In milliamps */
+static const unsigned int wm831x_usb_limits[] = {
+ 0,
+ 2,
+ 100,
+ 500,
+ 900,
+ 1500,
+ 1800,
+ 550,
+};
+
+static int wm831x_usb_limit_change(struct notifier_block *nb,
+ unsigned long limit, void *data)
+{
+ struct wm831x_power *wm831x_power = container_of(nb,
+ struct wm831x_power,
+ usb_notify);
+ unsigned int i, best;
+
+ /* Find the highest supported limit */
+ best = 0;
+ for (i = 0; i < ARRAY_SIZE(wm831x_usb_limits); i++) {
+ if (limit >= wm831x_usb_limits[i] &&
+ wm831x_usb_limits[best] < wm831x_usb_limits[i])
+ best = i;
+ }
+
+ dev_dbg(wm831x_power->wm831x->dev,
+ "Limiting USB current to %umA", wm831x_usb_limits[best]);
+
+ wm831x_set_bits(wm831x_power->wm831x, WM831X_POWER_STATE,
+ WM831X_USB_ILIM_MASK, best);
+
+ return 0;
+}
+
/*********************************************************************
* Battery properties
*********************************************************************/
@@ -607,8 +647,31 @@ static int wm831x_power_probe(struct platform_device *pdev)
}
}
+ if (wm831x_pdata && wm831x_pdata->usb_gadget) {
+ power->usb_charger =
+ usb_charger_find_by_name(wm831x_pdata->usb_gadget);
+ if (IS_ERR(power->usb_charger)) {
+ ret = PTR_ERR(power->usb_charger);
+ dev_err(&pdev->dev,
+ "Failed to find USB gadget: %d\n", ret);
+ goto err_bat_irq;
+ }
+
+ power->usb_notify.notifier_call = wm831x_usb_limit_change;
+
+ ret = usb_charger_register_notify(power->usb_charger,
+ &power->usb_notify);
+ if (ret != 0) {
+ dev_err(&pdev->dev,
+ "Failed to register notifier: %d\n", ret);
+ goto err_usb_charger;
+ }
+ }
+
return ret;
+err_usb_charger:
+ /* put_device on charger */
err_bat_irq:
--i;
for (; i >= 0; i--) {
@@ -637,6 +700,12 @@ static int wm831x_power_remove(struct platform_device *pdev)
struct wm831x *wm831x = wm831x_power->wm831x;
int irq, i;
+ if (wm831x_power->usb_charger) {
+ usb_charger_unregister_notify(wm831x_power->usb_charger,
+ &wm831x_power->usb_notify);
+ /* Free charger */
+ }
+
for (i = 0; i < ARRAY_SIZE(wm831x_bat_irqs); i++) {
irq = wm831x_irq(wm831x,
platform_get_irq_byname(pdev,
@@ -126,6 +126,9 @@ struct wm831x_pdata {
/** The driver should initiate a power off sequence during shutdown */
bool soft_shutdown;
+ /** dev_name of USB charger gadget to integrate with */
+ const char *usb_gadget;
+
int irq_base;
int gpio_base;
int gpio_defaults[WM831X_GPIO_NUM];