On Sat, 8 Nov 2025 at 00:22, BALATON Zoltan <[email protected]> wrote: > > On Fri, 7 Nov 2025, Peter Maydell wrote: > > If the guest incorrectly programs the lm4549 audio chip with a zero > > frequency, we will pass this to AUD_open_out(), which will complain: > > > > A bug was just triggered in AUD_open_out > > Save all your work and restart without audio > > I am sorry > > Context: > > audio: frequency=0 nchannels=2 fmt=S16 endianness=little > > > > The datasheet doesn't say what we should do here, only that the valid > > range for the freqency is 8000 to 48000 Hz; we choose to log the > > guest error and ignore an attempt to change the DAC rate to something > > outside the valid range. > > > > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/410 > > Signed-off-by: Peter Maydell <[email protected]> > > --- > > This bug has been around for so long and is a weird edge case whose > > only effect is to print a debug message, so it doesn't really seem > > worth cc'ing stable on. > > --- > > hw/audio/lm4549.c | 17 ++++++++++++++++- > > 1 file changed, 16 insertions(+), 1 deletion(-) > > > > diff --git a/hw/audio/lm4549.c b/hw/audio/lm4549.c > > index 745441bd790..bf711c49c04 100644 > > --- a/hw/audio/lm4549.c > > +++ b/hw/audio/lm4549.c > > @@ -15,6 +15,7 @@ > > > > #include "qemu/osdep.h" > > #include "hw/hw.h" > > +#include "qemu/log.h" > > #include "qemu/audio.h" > > #include "lm4549.h" > > #include "migration/vmstate.h" > > @@ -179,9 +180,23 @@ void lm4549_write(lm4549_state *s, > > break; > > > > case LM4549_PCM_Front_DAC_Rate: > > - regfile[LM4549_PCM_Front_DAC_Rate] = value; > > DPRINTF("DAC rate change = %i\n", value); > > > > + /* > > + * Valid sample rates are 4kHz to 48kHz. > > Commit message says minimum is 8kHz. One of these is likely incorrect. > Maybe a typo in commit message?
Whoops; yes, you're right, the commit message is the one that's wrong. The datasheet for this is at https://www.ti.com/lit/ds/symlink/lm4549b.pdf and it says 4kHz. -- PMM
