linux.git/drivers/usb/gadget/function, branch v5.12

usb: gadget: f_uac1: stop playback on function disable

2021-03-10T08:36:12+00:00

There is missing playback stop/cleanup in case of
gadget's ->disable callback that happens on
events like USB host resetting or gadget disconnection

Fixes: 0591bc236015 ("usb: gadget: add f_uac1 variant based on a new u_audio api")
Cc:  # 4.13+
Signed-off-by: Ruslan Bilovol 
Link: https://lore.kernel.org/r/1614599375-8803-3-git-send-email-ruslan.bilovol@gmail.com
Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_uac2: always increase endpoint max_packet_size by one audio slot

2021-03-10T08:36:12+00:00

As per UAC2 Audio Data Formats spec (2.3.1.1 USB Packets),
if the sampling rate is a constant, the allowable variation
of number of audio slots per virtual frame is +/- 1 audio slot.

It means that endpoint should be able to accept/send +1 audio
slot.

Previous endpoint max_packet_size calculation code
was adding sometimes +1 audio slot due to DIV_ROUND_UP
behaviour which was rounding up to closest integer.
However this doesn't work if the numbers are divisible.

It had no any impact with Linux hosts which ignore
this issue, but in case of more strict Windows it
caused rejected enumeration

Thus always add +1 audio slot to endpoint's max packet size

Fixes: 913e4a90b6f9 ("usb: gadget: f_uac2: finalize wMaxPacketSize according to bandwidth")
Cc: Peter Chen 
Cc:  #v4.3+
Signed-off-by: Ruslan Bilovol 
Link: https://lore.kernel.org/r/1614599375-8803-2-git-send-email-ruslan.bilovol@gmail.com
Signed-off-by: Greg Kroah-Hartman

USB: gadget: u_ether: Fix a configfs return code

2021-03-10T08:36:12+00:00

If the string is invalid, this should return -EINVAL instead of 0.

Fixes: 73517cf49bd4 ("usb: gadget: add RNDIS configfs options for class/subclass/protocol")
Cc: stable 
Acked-by: Lorenzo Colitti 
Signed-off-by: Dan Carpenter 
Link: https://lore.kernel.org/r/YCqZ3P53yyIg5cn7@mwanda
Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_serial: Remove old tasklet comments

2021-01-19T12:30:52+00:00

Update old comments as of 8b4c62aef6f (usb: gadget: u_serial: process RX
in workqueue instead of tasklet).

Acked-by: Felipe Balbi 
Signed-off-by: Davidlohr Bueso 
Link: https://lore.kernel.org/r/20210119001321.127750-1-dave@stgolabs.net
Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_audio: clean up locking

2021-01-18T17:43:09+00:00

snd_pcm_stream_lock() is held when the ALSA .trigger() callback is called.
The lock of 'struct uac_rtd_params' is not necessary since all its locking
operation are done under the snd_pcm_stream_lock() too.

Also, usb_request .complete() is called with irqs disabled, so saving and
restoring the irqs is not necessary.

Acked-by: Felipe Balbi 
Signed-off-by: Jerome Brunet 
Link: https://lore.kernel.org/r/20210118084931.322861-1-jbrunet@baylibre.com
Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_audio: remove struct uac_req

2021-01-18T17:43:09+00:00

'struct uac_req' purpose is to link 'struct usb_request' to the
corresponding 'struct uac_rtd_params'. However member req is never
used. Using the context of the usb request, we can keep track of the
corresponding 'struct uac_rtd_params' just as well, without allocating
extra memory.

Acked-by: Felipe Balbi 
Signed-off-by: Jerome Brunet 
Link: https://lore.kernel.org/r/20210118084642.322510-4-jbrunet@baylibre.com
Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_audio: factorize ssize to alsa fmt conversion

2021-01-18T17:43:09+00:00

Factorize format related code common to the capture and playback path.

Acked-by: Felipe Balbi 
Signed-off-by: Jerome Brunet 
Link: https://lore.kernel.org/r/20210118084642.322510-3-jbrunet@baylibre.com
Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_audio: Free requests only after callback

2021-01-18T17:43:09+00:00

As per the kernel doc for usb_ep_dequeue(), it states that "this
routine is asynchronous, that is, it may return before the completion
routine runs". And indeed since v5.0 the dwc3 gadget driver updated
its behavior to place dequeued requests on to a cancelled list to be
given back later after the endpoint is stopped.

The free_ep() was incorrectly assuming that a request was ready to
be freed after calling dequeue which results in a use-after-free
in dwc3 when it traverses its cancelled list. Fix this by moving
the usb_ep_free_request() call to the callback itself in case the
ep is disabled.

Fixes: eb9fecb9e69b0 ("usb: gadget: f_uac2: split out audio core")
Reported-and-tested-by: Ferry Toth 
Reviewed-and-tested-by: Peter Chen 
Acked-by: Felipe Balbi 
Signed-off-by: Jack Pham 
Signed-off-by: Jerome Brunet 
Link: https://lore.kernel.org/r/20210118084642.322510-2-jbrunet@baylibre.com
Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_ether: support configuring interface names.

2021-01-15T15:08:53+00:00

This patch allows the administrator to configure the interface
name of a function using u_ether (e.g., eem, ncm, rndis).

Currently, all such interfaces, regardless of function type, are
always called usb0, usb1, etc. This makes it very cumbersome to
use more than one such type at a time, because userspace cannnot
easily tell the interfaces apart and apply the right
configuration to each one. Interface renaming in userspace based
on driver doesn't help, because the interfaces all have the same
driver. Without this patch, doing this require hacks/workarounds
such as setting fixed MAC addresses on the functions, and then
renaming by MAC address, or scraping configfs after each
interface is created to find out what it is.

Setting the interface name is done by writing to the same
"ifname" configfs attribute that reports the interface name after
the function is bound. The write must contain an interface
pattern such as "usb%d" (which will cause the net core to pick
the next available interface name starting with "usb").
This patch does not allow writing an exact interface name (as
opposed to a pattern) because if the interface already exists at
bind time, the bind will fail and the whole gadget will fail to
activate. This could be allowed in a future patch.

For compatibility with current userspace, when reading an ifname
that has not currently been set, the result is still "(unnamed
net_device)". Once a write to ifname happens, then reading ifname
will return whatever was last written.

Tested by configuring an rndis function and an ncm function on
the same gadget, and writing "rndis%d" to ifname on the rndis
function and "ncm%d" to ifname on the ncm function. When the
gadget was bound, the rndis interface was rndis0 and the ncm
interface was ncm0.

Signed-off-by: Lorenzo Colitti 
Link: https://lore.kernel.org/r/20210113234222.3272933-1-lorenzo@google.com
Signed-off-by: Greg Kroah-Hartman

usb/gadget: f_midi: Replace tasklet with work

2021-01-12T11:52:28+00:00

Currently a tasklet is used to transmit input substream buffer
data. However, tasklets have long been deprecated as being too
heavy on the system by running in irq context - and this is not
a performance critical path. If a higher priority process wants
to run, it must wait for the tasklet to finish before doing so.

Deferring work to a workqueue and executing in process context
should be fine considering the callback already does
f_midi_do_transmit() under the transmit_lock and thus changes in
semantics are ok regarding concurrency - tasklets being serialized
against itself.

Cc: Takashi Iwai 
Reviewed-by: Takashi Iwai 
Acked-by: Felipe Balbi 
Signed-off-by: Davidlohr Bueso 
Link: https://lore.kernel.org/r/20210111042855.73289-1-dave@stgolabs.net
Signed-off-by: Greg Kroah-Hartman