linux.git/drivers/usb/gadget/function/u_audio.c, branch v5.17

usb: gadget: u_audio: Subdevice 0 for capture ctls

2022-01-06T14:31:02+00:00

Both capture and playback alsa devices use subdevice 0. Yet capture-side
ctls are defined for subdevice 1. The patch sets subdevice 0 for them.

Fixes: 02de698ca812 ("usb: gadget: u_audio: add bi-directional volume and mute support")
Signed-off-by: Pavel Hofman 
Link: https://lore.kernel.org/r/20220105104643.90125-1-pavel.hofman@ivitera.com
Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_audio: fix calculations for small bInterval

2022-01-06T14:28:45+00:00

If bInterval is 1, then p_interval is 8000 and p_interval_mil is 8E9,
which is too big for a 32-bit value.  While the storage is indeed
64-bit, this value is used as the divisor in do_div() which will
truncate it into a uint32_t leading to incorrect calculated values.

Switch back to keeping the base value in struct snd_uac_chip which fits
easily into an int, meaning that the division can be done in two steps
with the divisor fitting safely into a uint32_t on both steps.

Fixes: 6fec018a7e70 ("usb: gadget: u_audio.c: Adding Playback Pitch ctl for sync playback")
Tested-by: Pavel Hofman 
Signed-off-by: John Keeping 
Link: https://lore.kernel.org/r/20220104183243.718258-1-john@metanate.com
Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_audio.c: Adding Playback Pitch ctl for sync playback

2021-10-13T11:59:43+00:00

EP IN is hard-coded as ASYNC both in f_uac1 and f_uac2 but u_audio sends
steady number of audio frames in each USB packet, without any control.

This patch adds 'Playback Pitch 1000000' ctl analogous to the existing
'Capture Pitch 1000000' ctl. The calculation of playback req->length in
u_audio_iso_complete respects the Playback Pitch ctl value to 1ppm now.

Max. value for Playback Pitch is configured by the existing parameter
uac2_opts->fb_max, used also for the Capture Pitch.

Since the EP IN packet size can be increased by uac2_opts->fb_max now,
maxPacketSize for the playback direction is calculated by the same
algorithm as for the async capture direction in
f_uac2.c:set_ep_max_packet_size.

Signed-off-by: Pavel Hofman 
Link: https://lore.kernel.org/r/20211013073934.36476-1-pavel.hofman@ivitera.com
Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_audio: EP-OUT bInterval in fback frequency

2021-09-14T08:32:06+00:00

The patch increases the bitshift in feedback frequency
calculation with EP-OUT bInterval value.

Tests have revealed that Win10 and OSX UAC2 drivers require
the feedback frequency to be based on the actual packet
interval instead of on the USB2 microframe. Otherwise they
ignore the feedback value. Linux snd-usb-audio driver
detects the applied bitshift automatically.

Tested-by: Henrik Enquist 
Signed-off-by: Pavel Hofman 
Cc: stable 
Link: https://lore.kernel.org/r/20210906130822.12256-1-pavel.hofman@ivitera.com
Signed-off-by: Greg Kroah-Hartman

Merge tag 'usb-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

2021-09-01T16:59:34+00:00

Pull USB / Thunderbolt updates from Greg KH:
 "Here is the big set of USB and Thunderbolt patches for 5.15-rc1.

  Nothing huge in here, just lots of constant forward progress on a
  number of different drivers and hardware support:

   - more USB 4/Thunderbolt support added

   - dwc3 driver updates and additions

   - usb gadget fixes and addtions for new types

   - udc gadget driver updates

   - host controller updates

   - removal of obsolete drivers

   - other minor driver updates

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'usb-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (148 commits)
  usb: isp1760: otg control register access
  usb: isp1760: use the right irq status bit
  usb: isp1760: write to status and address register
  usb: isp1760: fix qtd fill length
  usb: isp1760: fix memory pool initialization
  usb: typec: tcpm: Fix spelling mistake "atleast" -> "at least"
  usb: dwc2: Fix spelling mistake "was't" -> "wasn't"
  usb: renesas_usbhs: Fix spelling mistake "faile" -> "failed"
  usb: host: xhci-rcar: Don't reload firmware after the completion
  usb: xhci-mtk: allow bandwidth table rollover
  usb: mtu3: fix random remote wakeup
  usb: mtu3: return successful suspend status
  usb: xhci-mtk: Do not use xhci's virt_dev in drop_endpoint
  usb: xhci-mtk: modify the SOF/ITP interval for mt8195
  usb: xhci-mtk: add a member of num_esit
  usb: xhci-mtk: check boundary before check tt
  usb: xhci-mtk: update fs bus bandwidth by bw_budget_table
  usb: xhci-mtk: fix issue of out-of-bounds array access
  usb: xhci-mtk: support option to disable usb2 ports
  usb: xhci-mtk: fix use-after-free of mtk->hcd
  ...

usb: gadget: u_audio: fix race condition on endpoint stop

2021-08-27T14:07:23+00:00

If the endpoint completion callback is call right after the ep_enabled flag
is cleared and before usb_ep_dequeue() is call, we could do a double free
on the request and the associated buffer.

Fix this by clearing ep_enabled after all the endpoint requests have been
dequeued.

Fixes: 7de8681be2cd ("usb: gadget: u_audio: Free requests only after callback")
Cc: stable 
Reported-by: Thinh Nguyen 
Signed-off-by: Jerome Brunet 
Link: https://lore.kernel.org/r/20210827092927.366482-1-jbrunet@baylibre.com
Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_uac2: fixup feedback endpoint stop

2021-08-27T14:06:53+00:00

When the uac2 function is stopped, there seems to be an issue reported on
some platforms (Intel Merrifield at least)

BUG: kernel NULL pointer dereference, address: 0000000000000008
...
RIP: 0010:dwc3_gadget_del_and_unmap_request+0x19/0xe0
...
Call Trace:
 dwc3_remove_requests.constprop.0+0x12f/0x170
 __dwc3_gadget_ep_disable+0x7a/0x160
 dwc3_gadget_ep_disable+0x3d/0xd0
 usb_ep_disable+0x1c/0x70
 u_audio_stop_capture+0x79/0x120 [u_audio]
 afunc_set_alt+0x73/0x80 [usb_f_uac2]
 composite_setup+0x224/0x1b90 [libcomposite]

The issue happens only when the gadget is using the sync type "async", not
"adaptive". This indicates that problem is coming from the feedback
endpoint, which is only used with async synchronization mode.

The problem is that request is freed regardless of usb_ep_dequeue(), which
ends up badly if the request is not actually dequeued yet.

Update the feedback endpoint free function to release the endpoint the same
way it is done for the data endpoint, which takes care of the problem.

Fixes: 24f779dac8f3 ("usb: gadget: f_uac2/u_audio: add feedback endpoint support")
Reported-by: Ferry Toth 
Tested-by: Ferry Toth 
Acked-by: Felipe Balbi 
Signed-off-by: Jerome Brunet 
Link: https://lore.kernel.org/r/20210827075853.266912-1-jbrunet@baylibre.com
Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_audio: add bi-directional volume and mute support

2021-07-21T08:10:11+00:00

USB Audio Class 1/2 have ability to change device's
volume and mute by USB Host through class-specific control
requests. Device also can notify Host about volume/mute
change on its side through optional interrupt endpoint.

This patch adds Volume and Mute ALSA controls which can be
used by user to send and receive notifications to/from
the USB Host about Volume and Mute change.

These params come from f_uac* so volume and mute controls
will be created only if the function support and enable
each explicitly

Signed-off-by: Ruslan Bilovol 
Signed-off-by: Pavel Hofman 
Link: https://lore.kernel.org/r/20210712125529.76070-3-pavel.hofman@ivitera.com
Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_audio: add real feedback implementation

2021-06-09T09:26:49+00:00

This adds interface between userspace and feedback endpoint to report real
feedback frequency to the Host.

Current implementation adds new userspace interface ALSA mixer control
"Capture Pitch 1000000" (similar to aloop driver's "PCM Rate Shift 100000"
mixer control)

Value in PPM is chosen to have correction value agnostic of the actual HW
rate, which the application is not necessarily dealing with, while still
retaining a good enough precision to allow smooth clock correction on the
playback side, if necessary.

Similar to sound/usb/endpoint.c, a slow down is allowed up to 25%. This
has no impact on the required bandwidth. Speedup correction has an impact
on the bandwidth reserved for the isochronous endpoint. The default
allowed speedup is 500ppm. This seems to be more than enough but, if
necessary, this is configurable through a module parameter. The reserved
bandwidth is rounded up to the next packet size.

Usage of this new control is easy to implement in existing userspace tools
like alsaloop from alsa-utils.

Signed-off-by: Ruslan Bilovol 
Signed-off-by: Jerome Brunet 
Link: https://lore.kernel.org/r/20210603220104.1216001-4-jbrunet@baylibre.com
Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_uac2/u_audio: add feedback endpoint support

2021-06-09T09:26:49+00:00

As per USB and UAC2 specs, asynchronous audio sink endpoint
requires explicit synchronization mechanism (Isochronous
Feedback Endpoint)

Implement feedback companion endpoint for ISO OUT endpoint

This patch adds all required infrastructure and USB requests
handling for feedback endpoint. Syncrhonization itself is
still dummy (feedback ep always reports 'nomimal frequency'
 e.g. no adjustement is needed). This satisfies hosts that
require feedback endpoint (like Win10) and poll it periodically

Actual synchronization mechanism should be implemented
separately

Signed-off-by: Ruslan Bilovol 
Signed-off-by: Jerome Brunet 
Link: https://lore.kernel.org/r/20210603220104.1216001-2-jbrunet@baylibre.com
Signed-off-by: Greg Kroah-Hartman