The UAC2 function driver currently responds to all packets at all times
with wMaxPacketSize packets. That results in way too fast audio
playback as the function driver (which is in fact supposed to define
the audio stream pace) delivers as fast as it can.
Fix this by sizing each packet correctly with the following steps:
a) Set the packet's size by dividing the nominal data rate by the
playback endpoint's interval.
b) If there is a residual value from the calculation in a), add
it to a accumulator to keep track of it across packets.
c) If the accumulator has gathered at least the number of bytes
that are needed for one sample frame, increase the packet size.
This way, the packet size calculation will get rid of any kind of
imprecision that would otherwise occur with a simple division over
time.
Some of the variables that are needed while processing each packet
are pre-computed for performance reasons.
Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
With packet sizes other than 512, payloads in the packets may wrap
around the ALSA dma buffer partially, which leads to memory corruption
and audible clicks and pops in the audio stream at the moment, because
there is no boundary check before the memcpy().
In preparation to an implementation for smaller and dynamically sized
packets, we have to address such cases, and copy the payload in two
steps conditionally.
The 'src' and 'dst' approach doesn't work here anymore, as different
behavior is necessary in playback and capture cases. Thus, this patch
open-codes the routine now.
Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Add a simple container_of() wrapper to get a struct f_uac2_opts from a
struct struct audio_dev. Use it in two places where it is currently
open-coded.
Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
In afunc_bind() and afunc_set_alt(), &uac2->pdev.dev are used multiple
times. Adding a short-hand for them makes lines shorter so we can
remove some line wraps.
No functional change.
Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Restructure some code to make it easier to read.
While at it, return -ENOMEM instead of -EINVAL if
usb_ep_alloc_request() fails, and omit the logging in such cases
(the mm core will complain loud enough).
Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Add support for using f_uac2 function as a component of a gadget
composed with configfs.
Tested-by: Sebastian Reimers <sebastian.reimers@googlemail.com>
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Use the new usb_gstring_attach interface.
Tested-by: Sebastian Reimers <sebastian.reimers@googlemail.com>
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
There are no users of the old interface left, so it can be removed.
Tested-by: Sebastian Reimers <sebastian.reimers@googlemail.com>
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Converting uac2 to the new function interface requires converting
the USB uac2's function code and its users.
This patch converts the f_uac2.c to the new function interface.
The file is now compiled into a separate usb_f_uac2.ko module.
The old function interface is provided by means of a preprocessor
conditional directives. After all users are converted, the old interface
can be removed.
Tested-by: Sebastian Reimers <sebastian.reimers@googlemail.com>
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Eliminate static struct *agdev_g from f_uac2.c.
It is used for freeing its memory, but the same address can be found
by calling container_of in afunc_unbind(). This implies eliminating
uac2_unbind_config(). The audio_config_driver in audio.c does not have
its unbind method any more. It has been used only when uac2 is used,
so uac2 itself can handle unbinding in afunc_unbind().
Tested-by: Sebastian Reimers <sebastian.reimers@googlemail.com>
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
The pcm playback and capture sample size format was fixed
SNDRV_PCM_FMTBIT_S16_LE.
This patch respects also 16, 24 and 32 bit p_ssize and c_ssize values.
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sebastian Reimers <sebastian.reimers@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
The drivers/usb/gadget directory contains many files.
Files which are related can be distributed into separate directories.
This patch moves the USB functions implementations into a separate directory.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Daniel Mack