commit 0b00583ecacb0b51712a5ecd34cf7e6684307c67 upstream.
USB_DEVICE(0x1901, 0x0006) may send data before cdc_acm is ready, which
may be misinterpreted in the default N_TTY line discipline.
Signed-off-by: Ian Ray <ian.ray@gehealthcare.com>
Acked-by: Oliver Neuku <oneukum@suse.com>
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20240814072905.2501-1-ian.ray@gehealthcare.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 66aad7d8d3ec5a3a8ec2023841bcec2ded5f65c9 ]
In ACM support for sending breaks to devices is optional.
If a device says that it doenot support sending breaks,
the host must respect that.
Given the number of optional features providing tty operations
for each combination is not practical and errors need to be
returned dynamically if unsupported features are requested.
In case a device does not support break, we want the tty layer
to treat that like it treats drivers that statically cannot
support sending a break. It ignores the inability and does nothing.
This patch uses EOPNOTSUPP to indicate that.
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Fixes: 9e98966c7bb94 ("tty: rework break handling")
Link: https://lore.kernel.org/r/20231207132639.18250-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
