It allows to reset prevent_medium_removal flag and "eject" the image.
This can be useful to free the drive from a hunging host or if the host
continues to use the drive even after unmounting (Linux does this).
It's also a bit like using an unfolded paperclip on an optical drive.
Previously, the undocumented method of sending SIGUSR1 to a special
"file-storage" kernel thread could be used for these purposes,
but when using multiple storages there was no way to distinguish
one from the other, so we had to send a signal to everyone.
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Maxim Devaev <mdevaev@gmail.com>
Link: https://lore.kernel.org/r/20220711102956.19642-1-mdevaev@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a configfs entry, "function_name", to change the iInterface field
for VideoControl. This name is used on host devices for user selection,
useful when multiple cameras are present. The default will remain "UVC
Camera".
Signed-off-by: Dan Vacura <w36195@motorola.com>
Link: https://lore.kernel.org/r/20220401160447.5919-1-w36195@motorola.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Allow setting configfs params p_hs_bint/c_hs_bint to 0. If they are set
to 0, determine the largest bInterval (4 to 1) for which the required
bandwidth of the max samplerate fits the max allowed packet size. If the
required bandwidth exceeds max bandwidth for single-packet mode
(ep->mc=1), keep bInterval at 1.
The FS speed is left at fixed bInterval=1.
If for any speed the required bandwidth exceeds the max bandwidth
corresponding to the selected/determined bInterval, print a warning.
Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Link: https://lore.kernel.org/r/20220127114331.41367-4-pavel.hofman@ivitera.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Allow configuring the HS/SS bInterval through configfs, via
parameters p_hs_bint/c_hs_bint separately for playback/capture.
The default param values are left at the original 4.
Suggested-by: John Keeping <john@metanate.com>
Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Link: https://lore.kernel.org/r/20220127114331.41367-2-pavel.hofman@ivitera.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This adds "function_name" configfs entry to change string value
of the iInterface field. This field will be shown in Windows' audio
settings panel, so being able to change it is useful. It will default
to "Source/Sink" just as before.
Signed-off-by: Yunhao Tian <t123yh.xyz@gmail.com>
Link: https://lore.kernel.org/r/20220122112446.1415547-2-t123yh.xyz@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This adds "function_name" configfs entry to change string value
of the iInterface field. This field will be shown in Windows' audio
settings panel, so being able to change it is useful. It will default
to "AC Interface" just as before if unchanged.
Signed-off-by: Yunhao Tian <t123yh.xyz@gmail.com>
Link: https://lore.kernel.org/r/20220122112446.1415547-1-t123yh.xyz@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A list of sampling rates can be specified via configfs. All enabled
sampling rates are sent to the USB host on request. When the host
selects a sampling rate the internal active rate is updated.
Config strings with single value stay compatible with the previous version.
Multiple samplerates passed as configuration arrays to g_audio module
when built for f_uac1.
Signed-off-by: Julian Scheel <julian@jusst.de>
Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Link: https://lore.kernel.org/r/20220121155308.48794-7-pavel.hofman@ivitera.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A list of sampling rates can be specified via configfs. All enabled
sampling rates are sent to the USB host on request. When the host
selects a sampling rate, the internal active rate (stored in
struct f_uac2) is updated.
The gadget no longer supports only one frequency. Therefore USB strings
corresponding to the clock sources are renamed from specific Hz value to
general names Input clock/Output clock.
Config strings with single value stay compatible with the previous
version.
Multiple samplerates passed as configuration arrays to g_audio module
when built for f_uac2.
Signed-off-by: Julian Scheel <julian@jusst.de>
Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Link: https://lore.kernel.org/r/20220121155308.48794-6-pavel.hofman@ivitera.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tables are separated with tabs and spaces mixed together, leading
to malformation. Changed the characters all into spaces to solve this
issue.
Signed-off-by: Hu Haowen <src.res@email.cn>
Link: https://lore.kernel.org/r/20210805040146.121526-1-src.res@email.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This adds bi-directional (host->device, device->host)
volume/mute support to the f_uac1 driver by adding
Feature Units and interrupt endpoint.
Currently only master channel is supported.
Volume and mute are configurable through configfs,
by default volume has -100..0 dB range with 1 dB step.
Similar to existing flexible endpoints configuration,
Feature Unit won't be added to the topology if both
mute and volume are not enabled, also interrupt endpoint
isn't added to the device if no feature unit is present
Signed-off-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Link: https://lore.kernel.org/r/20210712125529.76070-5-pavel.hofman@ivitera.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This adds bi-directional (host->device, device->host)
volume/mute support to the f_uac2 driver by adding
Feature Units and interrupt endpoint.
Currently only master channel is supported.
Volume and mute are configurable through configfs,
by default volume has -100..0 dB range with 1 dB step.
Similar to existing flexible endpoints configuration,
Feature Unit won't be added to the topology if both
mute and volume are not enabled, also interrupt endpoint
isn't added to the device if no feature unit is present
Signed-off-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Link: https://lore.kernel.org/r/20210712125529.76070-4-pavel.hofman@ivitera.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 <ruslan.bilovol@gmail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20210603220104.1216001-4-jbrunet@baylibre.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Current f_uac2 USB OUT (aka 'capture') synchronization
implements 'ASYNC' scenario which means USB Gadget has
it's own freerunning clock and can update Host about
real clock frequency through feedback endpoint so Host
can align number of samples sent to the USB gadget to
prevent overruns/underruns
In case if Gadget can has no it's internal clock and
can consume audio samples at any rate (for example,
on the Gadget side someone records audio directly to
a file, or audio samples are played through an
external DAC as soon as they arrive), UAC2 spec
suggests 'ADAPTIVE' synchronization type.
Change UAC2 driver to make it configurable through
additional 'c_sync' configfs file.
Default remains 'asynchronous' with possibility to
switch it to 'adaptive'
Signed-off-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20210603220104.1216001-3-jbrunet@baylibre.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 <lorenzo@google.com>
Link: https://lore.kernel.org/r/20210113234222.3272933-1-lorenzo@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
While there are a mix of things here, most of the stuff
were written from Kernel developer's PoV. So, add them to
the driver-api book.
A follow up for this patch would be to move documents from
there that are specific to sysadmins, adding them to the
admin-guide.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
