When userland echoes 8bit characters to /dev/synth with e.g.
echo -e '\xe9' > /dev/synth
synth_write would get characters beyond 0x7f, and thus negative when
char is signed. When given to synth_buffer_add which takes a u16, this
would sign-extend and produce a U+ffxy character rather than U+xy.
Users thus get garbled text instead of accents in their output.
Let's fix this by making sure that we read unsigned characters.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Fixes: 89fc2ae80b ("speakup: extend synth buffer to 16bit unicode characters")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240204155736.2oh4ot7tiaa2wpbh@begin
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Users needing it with the dectlk synth report that a 100ms flush delay
is still noticeable and prefer to set it to e.g. 10ms. This leaves the
default to 4000ms (since hitting it is a sign that the cable is faulty
and should be replaced), but allows to set it as short as 10ms.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Link: https://lore.kernel.org/r/20220205232957.bc6o6yyt5hitg754@begin
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This was missed while introducing the tty-based serial access.
The only remaining use of wait_for_xmitr with tty-based access is in
spk_synth_is_alive_restart to check whether the synth can be restarted.
With tty-based this is up to the tty layer to cope with the buffering
etc. so we can just say yes.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Link: https://lore.kernel.org/r/20200804160637.x3iycau5izywbgzl@function
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
