linux/include
Andrey Konovalov 97df5e5758 usb: raw-gadget: fix gadget endpoint selection
Currently automatic gadget endpoint selection based on required features
doesn't work. Raw Gadget tries iterating over the list of available
endpoints and finding one that has the right direction and transfer type.
Unfortunately selecting arbitrary gadget endpoints (even if they satisfy
feature requirements) doesn't work, as (depending on the UDC driver) they
might have fixed addresses, and one also needs to provide matching
endpoint addresses in the descriptors sent to the host.

The composite framework deals with this by assigning endpoint addresses
in usb_ep_autoconfig() before enumeration starts. This approach won't work
with Raw Gadget as the endpoints are supposed to be enabled after a
set_configuration/set_interface request from the host, so it's too late to
patch the endpoint descriptors that had already been sent to the host.

For Raw Gadget we take another approach. Similarly to GadgetFS, we allow
the user to make the decision as to which gadget endpoints to use.

This patch adds another Raw Gadget ioctl USB_RAW_IOCTL_EPS_INFO that
exposes information about all non-control endpoints that a currently
connected UDC has. This information includes endpoints addresses, as well
as their capabilities and limits to allow the user to choose the most
fitting gadget endpoint.

The USB_RAW_IOCTL_EP_ENABLE ioctl is updated to use the proper endpoint
validation routine usb_gadget_ep_match_desc().

These changes affect the portability of the gadgets that use Raw Gadget
when running on different UDCs. Nevertheless, as long as the user relies
on the information provided by USB_RAW_IOCTL_EPS_INFO to dynamically
choose endpoint addresses, UDC-agnostic gadgets can still be written with
Raw Gadget.

Fixes: f2c2e71764 ("usb: gadget: add raw-gadget interface")
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
2020-05-14 12:30:17 +03:00
..
acpi Additional ACPI updates for 5.7-rc1 2020-04-06 10:35:06 -07:00
asm-generic arch: split MODULE_ARCH_VERMAGIC definitions out to <asm/vermagic.h> 2020-04-23 10:50:26 +09:00
clocksource
crypto crypto: curve25519 - do not pollute dispatcher based on assembler 2020-04-09 00:01:59 +09:00
drm drm/bridge: analogix_dp: Split bind() into probe() and real bind() 2020-04-09 10:29:35 +02:00
dt-bindings RISC-V Patches for the 5.7 Merge Window, Part 1 2020-04-09 10:51:30 -07:00
keys
kunit
kvm
linux block-5.7-2020-05-09 2020-05-10 11:16:07 -07:00
math-emu
media
misc
net net: flow_offload: skip hw stats check for FLOW_ACTION_HW_STATS_DONT_CARE 2020-05-06 20:13:10 -07:00
pcmcia
ras
rdma
scsi
soc net: dsa: ocelot: the MAC table on Felix is twice as large 2020-05-06 17:15:24 -07:00
sound ASoC: Fixes for v5.7 2020-04-21 21:41:36 +02:00
target
trace block-5.7-2020-05-09 2020-05-10 11:16:07 -07:00
uapi usb: raw-gadget: fix gadget endpoint selection 2020-05-14 12:30:17 +03:00
vdso vdso/datapage: Use correct clock mode name in comment 2020-04-20 19:19:52 +02:00
video
xen xen: Use evtchn_type_t as a type for event channels 2020-04-07 12:12:54 +02:00