Re: [PATCH] hw/misc: i2c-echo: add tracing

[Titus Rwantare]

On Tue, 21 Jan 2025 at 02:43, Philippe Mathieu-Daudé <philmd@linaro.org> wrote:
>
> Hi Titus,
>
> On 21/1/25 11:36, Titus Rwantare wrote:
> > This has been useful when debugging when unsure if the guest is
> > generating i2c traffic.
> >
> > Signed-off-by: Titus Rwantare <titusr@google.com>
> > ---
> >   hw/misc/i2c-echo.c   | 13 +++++++++++++
> >   hw/misc/trace-events |  5 +++++
> >   2 files changed, 18 insertions(+)
> >
> > diff --git a/hw/misc/i2c-echo.c b/hw/misc/i2c-echo.c
> > index 5ae3d0817e..06110e0f8e 100644
> > --- a/hw/misc/i2c-echo.c
> > +++ b/hw/misc/i2c-echo.c
> > @@ -13,6 +13,7 @@
> >   #include "qemu/main-loop.h"
> >   #include "block/aio.h"
> >   #include "hw/i2c/i2c.h"
> > +#include "trace.h"
> >
> >   #define TYPE_I2C_ECHO "i2c-echo"
> >   OBJECT_DECLARE_SIMPLE_TYPE(I2CEchoState, I2C_ECHO)
> > @@ -80,11 +81,19 @@ static int i2c_echo_event(I2CSlave *s, enum i2c_event 
> > event)
> >       case I2C_START_RECV:
> >           state->pos = 0;
> >
> > +        trace_i2c_echo_event(DEVICE(s)->canonical_path, "I2C_START_RECV");
> >           break;
> >
> >       case I2C_START_SEND:
> >           state->pos = 0;
> >
> > +        trace_i2c_echo_event(DEVICE(s)->canonical_path, "I2C_START_SEND");
> > +        break;
> > +
> > +    case I2C_START_SEND_ASYNC:
> > +        state->pos = 0;
> > +
> > +        trace_i2c_echo_event(DEVICE(s)->canonical_path, 
> > "I2C_START_SEND_ASYNC");
>
> This patch is doing a bit more that what it describes, since now
> START_SEND_ASYNC returns 0x00 instead of 0xff (besides updating pos).
>
> Please split as one patch per logical change.
>
> Thanks!
>
> Phil.
>

I've removed the async case from the patch as it's not something that
has come up.
- Titus