linux_dsm_epyc7002/sound
Clemens Ladisch 1ca8b20130 ALSA: usb-audio: prevent CH345 multiport output SysEx corruption
The CH345 USB MIDI chip has two output ports.  However, they are
multiplexed through one pin, and the number of ports cannot be reduced
even for hardware that implements only one connector, so for those
devices, data sent to either port ends up on the same hardware output.
This becomes a problem when both ports are used at the same time, as
longer MIDI commands (such as SysEx messages) are likely to be
interrupted by messages from the other port, and thus to get lost.

It would not be possible for the driver to detect how many ports the
device actually has, except that in practice, _all_ devices built with
the CH345 have only one port.  So we can just ignore the device's
descriptors, and hardcode one output port.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: stable@vger.kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-11-16 08:59:24 +01:00
..
aoa
arm
atmel
core ALSA: Constify ratden/ratnum constraints 2015-10-28 11:42:22 +01:00
drivers
firewire ALSA: dice: fix detection of Loud devices 2015-11-14 17:50:57 +01:00
hda ALSA: hda - Add / fix kernel doc comments 2015-10-28 12:37:29 +01:00
i2c
isa
mips
oss
parisc
pci ALSA: hda - Fix noise on Dell Latitude E6440 2015-11-14 17:49:20 +01:00
pcmcia
ppc
sh
soc ASoC: Updates for v4.4 2015-10-26 12:14:49 +01:00
sparc
spi
synth
usb ALSA: usb-audio: prevent CH345 multiport output SysEx corruption 2015-11-16 08:59:24 +01:00
ac97_bus.c
Kconfig
last.c
Makefile
sound_core.c sound: fix check for error condition of register_chrdev() 2015-11-07 11:14:30 +01:00
sound_firmware.c