On Mon, Feb 18, 2019 at 12:48 PM sxau...@163.com <sxau...@163.com> wrote:
>
> Hi , Shubhrajyoti
>
> >Hi ,
> >On Sat, Feb 16, 2019 at 1:21 PM sxau...@163.com <sxau...@163.com> wrote:
> >>
> >> >Hi Sxauwsk,
> >> >
> >> >On Wed, Jan 30, 2019 at 3:13 PM sxauwsk <sxau...@163.com> wrote:
> >> >>
> >> >> When the adapter receive error interrupts, such as NACK, arbitration
> >> >> lost,
> >> >> cdns_i2c_master_xfer return to the caller directly instead of resuming
> >> >> the adapter which resulted in the adapter being out of control.
> >> >>
> >> >> So when driver detect err_status then try to repair and fix it.
> >> >>
> >> >> Signed-off-by: sxauwsk <sxau...@163.com>
> >> >> ---
> >> >> drivers/i2c/busses/i2c-cadence.c | 12 +++++++-----
> >> >> 1 file changed, 7 insertions(+), 5 deletions(-)
> >> >>
> >> >> diff --git a/drivers/i2c/busses/i2c-cadence.c
> >> >> b/drivers/i2c/busses/i2c-cadence.c
> >> >> index b13605718291..e10048d7524a 100644
> >> >> --- a/drivers/i2c/busses/i2c-cadence.c
> >> >> +++ b/drivers/i2c/busses/i2c-cadence.c
> >> >> @@ -548,10 +548,6 @@ static int cdns_i2c_process_msg(struct cdns_i2c
> >> >> *id, struct i2c_msg *msg,
> >> >> cdns_i2c_writereg(CDNS_I2C_IXR_ALL_INTR_MASK,
> >> >> CDNS_I2C_IDR_OFFSET);
> >> >>
> >> >> - /* If it is bus arbitration error, try again */
> >> >> - if (id->err_status & CDNS_I2C_IXR_ARB_LOST)
> >> >> - return -EAGAIN;
> >> >> -
> >> >> return 0;
> >> >> }
> >> >>
> >> >> @@ -617,13 +613,19 @@ static int cdns_i2c_master_xfer(struct
> >> >> i2c_adapter *adap, struct i2c_msg *msgs,
> >> >> id->bus_hold_flag = 0;
> >> >>
> >> >> ret = cdns_i2c_process_msg(id, msgs, adap);
> >> >> - if (ret)
> >> >> + if (!ret)
> >> >> goto out;
> >> >>
> >> >In case the Arbitration error happend the cdns_i2c_process_msg would
> >> >return 0
> >> >and we will miss the check below.
> >> >
> >> >Am I missing something ?
> >> >
> >> >> /* Report the other error interrupts to application */
> >> >> if (id->err_status) {
> >> >> cdns_i2c_master_reset(adap);
> >> >>
> >> >> + /* If it is bus arbitration error, try again */
> >> >> + if (id->err_status & CDNS_I2C_IXR_ARB_LOST) {
> >> >> + ret = -EAGAIN;
> >> >> + goto out;
> >> >> + }
> >> >> +
> >> >> if (id->err_status & CDNS_I2C_IXR_NACK) {
> >> >> ret = -ENXIO;
> >> >> goto out;
> >> >> --
> >> >> 2.19.2
> >> >>
> >> >>
> >>
> >> In cdns_i2c_process_msg process, when detect arbitration lost error return
> >> -EAGAIN to cdns_i2c_master_xfer, not return 0
> >> that mean cdns_i2c_process_msg just go out ignore error check and
> >> problem occur, So we should do something when arbitration error detect.
> >
> >Arbitration lost is fine how about other errors like NACK.
>
> >> >> ret = cdns_i2c_process_msg(id, msgs, adap);
> >> >> - if (ret)
> >> >> + if (!ret)
> >> >> goto out;
>
> Yes, you're right, This place I should't make any change, perfect solution!
>
> >> >>
> >> >> - /* If it is bus arbitration error, try again */
> >> >> - if (id->err_status & CDNS_I2C_IXR_ARB_LOST)
> >> >> - return -EAGAIN;
> >> >> -
> >> >> return 0;
> >> >> }
>
>
> >> >> /* Report the other error interrupts to application */
> >> >> if (id->err_status) {
> >> >> cdns_i2c_master_reset(adap);
> >> >>
> >> >> + /* If it is bus arbitration error, try again */
> >> >> + if (id->err_status & CDNS_I2C_IXR_ARB_LOST) {
> >> >> + ret = -EAGAIN;
> >> >> + goto out;
> >> >> + }
> >> >> +
>
> Maybe Just remove Arbitration lost Detect part from cdns_i2c_process_msg
> function, then add to cdns_i2c_master_xfer, Do you think?
I agree.
>
>
>
>
