From 8280de6ab07b4c63eb607662754f151e539031a1 Mon Sep 17 00:00:00 2001 From: Wesley Cheng Date: Tue, 29 Dec 2020 15:03:30 -0800 Subject: [PATCH] usb: gadget: composite: Split composite reset and disconnect Add a specific composite reset API to differentiate between disconnect and reset events. This is needed for adjusting the current draw accordingly based on the USB battery charging specification. The device is only allowed to draw the 500/900 mA (HS/SS) while in the CONFIGURED state, and only 100 mA in the connected and UNCONFIGURED state. Reviewed-by: Peter Chen Signed-off-by: Wesley Cheng Link: https://lore.kernel.org/r/1609283011-21997-3-git-send-email-wcheng@codeaurora.org Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/composite.c | 21 +++++++++++++++++++-- include/linux/usb/composite.h | 2 ++ 2 files changed, 21 insertions(+), 2 deletions(-) diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c index c6d455f2bb92..86e86a005e25 100644 --- a/drivers/usb/gadget/composite.c +++ b/drivers/usb/gadget/composite.c @@ -2036,7 +2036,7 @@ done: return value; } -void composite_disconnect(struct usb_gadget *gadget) +static void __composite_disconnect(struct usb_gadget *gadget) { struct usb_composite_dev *cdev = get_gadget_data(gadget); unsigned long flags; @@ -2053,6 +2053,23 @@ void composite_disconnect(struct usb_gadget *gadget) spin_unlock_irqrestore(&cdev->lock, flags); } +void composite_disconnect(struct usb_gadget *gadget) +{ + usb_gadget_vbus_draw(gadget, 0); + __composite_disconnect(gadget); +} + +void composite_reset(struct usb_gadget *gadget) +{ + /* + * Section 1.4.13 Standard Downstream Port of the USB battery charging + * specification v1.2 states that a device connected on a SDP shall only + * draw at max 100mA while in a connected, but unconfigured state. + */ + usb_gadget_vbus_draw(gadget, 100); + __composite_disconnect(gadget); +} + /*-------------------------------------------------------------------------*/ static ssize_t suspended_show(struct device *dev, struct device_attribute *attr, @@ -2373,7 +2390,7 @@ static const struct usb_gadget_driver composite_driver_template = { .unbind = composite_unbind, .setup = composite_setup, - .reset = composite_disconnect, + .reset = composite_reset, .disconnect = composite_disconnect, .suspend = composite_suspend, diff --git a/include/linux/usb/composite.h b/include/linux/usb/composite.h index a2d229ab63ba..5646dad886e6 100644 --- a/include/linux/usb/composite.h +++ b/include/linux/usb/composite.h @@ -525,6 +525,8 @@ extern struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev, extern int usb_string_ids_n(struct usb_composite_dev *c, unsigned n); extern void composite_disconnect(struct usb_gadget *gadget); +extern void composite_reset(struct usb_gadget *gadget); + extern int composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl); extern void composite_suspend(struct usb_gadget *gadget); -- 2.11.0