[PATCH v17 2/4] usb: gadget: Support for the usb charger framework

[Baolin Wang]

For supporting the usb charger, it adds the usb_charger_init() and
usb_charger_exit() functions for usb charger initialization and exit.

It will report to the usb charger when the gadget state is changed,
then the usb charger can do the power things.

Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
Reviewed-by: Li Jun <jun.li@xxxxxxx>
Tested-by: Li Jun <jun.li@xxxxxxx>
---
 drivers/usb/gadget/udc/core.c |   19 ++++++++++++++++++-
 include/linux/usb/gadget.h    |    3 +++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c
index 9483489..90df022 100644
--- a/drivers/usb/gadget/udc/core.c
+++ b/drivers/usb/gadget/udc/core.c
@@ -25,6 +25,7 @@
 #include <linux/dma-mapping.h>
 #include <linux/workqueue.h>
 
+#include <linux/usb/charger.h>
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
 #include <linux/usb.h>
@@ -576,12 +577,17 @@ EXPORT_SYMBOL_GPL(usb_gadget_vbus_connect);
  * reporting how much power the device may consume.  For example, this
  * could affect how quickly batteries are recharged.
  *
+ * It will also notify the USB charger how much power the device may
+ * consume if there is a USB charger linking with the gadget.
+ *
  * Returns zero on success, else negative errno.
  */
 int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
 {
 	int ret = 0;
 
+	usb_charger_set_cur_limit_by_gadget(gadget, mA);
+
 	if (!gadget->ops->vbus_draw) {
 		ret = -EOPNOTSUPP;
 		goto out;
@@ -963,6 +969,9 @@ static void usb_gadget_state_work(struct work_struct *work)
 	struct usb_gadget *gadget = work_to_gadget(work);
 	struct usb_udc *udc = gadget->udc;
 
+	/* when the gadget state is changed, then report to USB charger */
+	usb_charger_plug_by_gadget(gadget, gadget->state);
+
 	if (udc)
 		sysfs_notify(&udc->dev.kobj, NULL, "state");
 }
@@ -1132,6 +1141,10 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
 	if (ret)
 		goto err4;
 
+	ret = usb_charger_init(gadget);
+	if (ret)
+		goto err5;
+
 	usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
 	udc->vbus = true;
 
@@ -1143,7 +1156,7 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
 			if (ret != -EPROBE_DEFER)
 				list_del(&driver->pending);
 			if (ret)
-				goto err5;
+				goto err6;
 			break;
 		}
 	}
@@ -1152,6 +1165,9 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
 
 	return 0;
 
+err6:
+	usb_charger_exit(gadget);
+
 err5:
 	device_del(&udc->dev);
 
@@ -1263,6 +1279,7 @@ void usb_del_gadget_udc(struct usb_gadget *gadget)
 	kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
 	flush_work(&gadget->work);
 	device_unregister(&udc->dev);
+	usb_charger_exit(gadget);
 	device_unregister(&gadget->dev);
 }
 EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 8e81f9e..82a0d63 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -24,6 +24,7 @@
 #include <linux/types.h>
 #include <linux/workqueue.h>
 #include <linux/usb/ch9.h>
+#include <linux/usb/charger.h>
 
 #define UDC_TRACE_STR_MAX	512
 
@@ -328,6 +329,7 @@ struct usb_gadget_ops {
  * @in_epnum: last used in ep number
  * @mA: last set mA value
  * @otg_caps: OTG capabilities of this gadget.
+ * @charger: Negotiate the power with the usb charger.
  * @sg_supported: true if we can handle scatter-gather
  * @is_otg: True if the USB device port uses a Mini-AB jack, so that the
  *	gadget driver must provide a USB OTG descriptor.
@@ -387,6 +389,7 @@ struct usb_gadget {
 	unsigned			in_epnum;
 	unsigned			mA;
 	struct usb_otg_caps		*otg_caps;
+	struct usb_charger		*charger;
 
 	unsigned			sg_supported:1;
 	unsigned			is_otg:1;
-- 
1.7.9.5