[PATCH 0/3] Add vbus draw support to DWC3

From: Wesley Cheng
Date: Tue Dec 29 2020 - 18:04:45 EST


Some devices are connected to standard downstream ports (SDP) and draw current
from them. The current rates are defined in the BC1.2 specification, and
highlights the different charge rates depending on the device state. The DWC3
gadget does not currently have a mechanism to notify external drivers about
how much current can be drawn.

The current rates are notified by the USB gadget layer, and the DWC3 gadget will
propagate this potentially to external charger drivers. Also, the USB gadget
needs to be fixed to only allow 100mA current draw when receiving a bus reset
from the host, as the BC1.2 specification states that this is the max current
draw possible when in the connected and unconfigured state.

Wesley Cheng (3):
usb: dwc3: gadget: Introduce a DWC3 VBUS draw callback
usb: gadget: composite: Split composite reset and disconnect
usb: gadget: configfs: Add a specific configFS reset callback

drivers/usb/dwc3/gadget.c | 11 +++++++++++
drivers/usb/gadget/composite.c | 21 +++++++++++++++++++--
drivers/usb/gadget/configfs.c | 24 +++++++++++++++++++++++-
include/linux/usb/composite.h | 2 ++
4 files changed, 55 insertions(+), 3 deletions(-)

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