[PATCH v7 2/4] i2c: npcm: Modify the client address assignment

[Tyrone Ting]

Hi Paul:

Thank you for your comment.

It'll be addressed in the next patch set.

Paul Menzel <pmenzel at molgen.mpg.de> 於 2024年10月21日 週一 下午3:01寫道：
>
> Dear Tyrone,
>
>
> Thank you for your patch.
>
> Am 21.10.24 um 08:27 schrieb Tyrone Ting:
> > From: Tyrone Ting <kfting at nuvoton.com>
> >
> > Store the client address earlier since it might get called in
> > the i2c_recover_bus() logic flow at the early stage of
> > npcm_i2c_master_xfer().
>
> Thank you for the description. For the summary/title it’d be great, if
> you were more specific. For example:
>
> i2c: npcm: Assign client address earlier for `i2c_recover_bus()`
>
> It’d be great if you noted the commit, your patch fixes, so it’s clear
> since when the problem has been present.
>
> > Signed-off-by: Tyrone Ting <kfting at nuvoton.com>
> > Reviewed-by: Tali Perry <tali.perry1 at gmail.com>
> > ---
> >   drivers/i2c/busses/i2c-npcm7xx.c | 20 +++++++++++++++++++-
> >   1 file changed, 19 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
> > index c96a25d37c14..a9a9b21f1f0b 100644
> > --- a/drivers/i2c/busses/i2c-npcm7xx.c
> > +++ b/drivers/i2c/busses/i2c-npcm7xx.c
> > @@ -2155,6 +2155,16 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
> >
> >       } while (time_is_after_jiffies(time_left) && bus_busy);
> >
> > +     /*
> > +      * Previously, the 7-bit address was stored and being converted to
> > +      * the address of event in the following call to npcm_i2c_master_start_xmit().
> > +      *
> > +      * Since there are cases that the i2c_recover_bus() gets called at the
> > +      * early stage of npcm_i2c_master_xfer(), the address of event is stored
> > +      * and then used in the i2c_recover_bus().
> > +      */
> > +     bus->dest_addr = i2c_8bit_addr_from_msg(msg0);
> > +
> >       /*
> >        * Check the BER (bus error) state, when ber_state is true, it means that the module
> >        * detects the bus error which is caused by some factor like that the electricity
> > @@ -2165,6 +2175,15 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
> >        * bus is busy.
> >        */
> >       if (bus_busy || bus->ber_state) {
> > +             /*
> > +              * Since the transfer might be a read operation, remove the I2C_M_RD flag
> > +              * from the bus->dest_addr for the i2c_recover_bus() call later.
> > +              *
> > +              * The i2c_recover_bus() uses the address in a write direction to recover
> > +              * the i2c bus if some error condition occurs.
> > +              */
> > +             bus->dest_addr &= ~I2C_M_RD;
> > +
> >               iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST);
> >               npcm_i2c_reset(bus);
> >               i2c_recover_bus(adap);
> > @@ -2172,7 +2191,6 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
> >       }
> >
> >       npcm_i2c_init_params(bus);
> > -     bus->dest_addr = slave_addr;
> >       bus->msgs = msgs;
> >       bus->msgs_num = num;
> >       bus->cmd_err = 0;
>
>
> Kind regards,
>
> Paul

Have a nice day.

Regards,
Tyrone