Re: [PATCH] i2c: spacemit: fix detect issue

Troy Mitchell
2025-11-06T01:07:05Z

On Wed, Nov 05, 2025 at 11:44:00PM +0100, Aurelien Jarno wrote:
> Hi,
>
> On 2025-11-03 15:06, Troy Mitchell wrote:
[...]
> > if (i2c->status & (SPACEMIT_SR_BED | SPACEMIT_SR_ALD)) {
> > spacemit_i2c_reset(i2c);
> > - return -EAGAIN;
> > + if (i2c->status & SPACEMIT_SR_ALD)
> > + return -EAGAIN;
> > }
>
> This makes the resulting code, while correct, complex to understand as
> it is now two really different errors, as you explained well in the
> commit message.
>
> I therefore suggest to organize the code as:
>
> /* Arbitration Loss Detected */
> if (i2c->status & SPACEMIT_SR_ALD) {
> spacemit_i2c_reset(i2c);
> return -EAGAIN;
> }
>
> /* Bus Error No ACK/NAK */
> if (i2c->status & SPACEMIT_SR_BED) {
> spacemit_i2c_reset(i2c);
> }
Thanks. I'll fix it in the next version.
>
>
> > return i2c->status & SPACEMIT_SR_ACKNAK ? -ENXIO : -EIO;
> > @@ -491,6 +492,8 @@ static int spacemit_i2c_xfer(struct i2c_adapter *adapt, struct i2c_msg *msgs, in
> >
> > spacemit_i2c_init(i2c);
> >
> > + spacemit_i2c_clear_int_status(i2c, SPACEMIT_I2C_INT_STATUS_MASK);
> > +
>
> This sounds good to start the transfer with a clean interrupt state. I
> just wonder if it should be moved to spacemit_i2c_init(), ie where the
> corresponding interrupts are enabled.
Uh, We can move it actually. But is it essentail?
>
> > spacemit_i2c_enable(i2c);
> >
> > ret = spacemit_i2c_wait_bus_idle(i2c);
>
> Anyway:
>
> Tested-by: Aurelien Jarno <aurelien@aurel32.net>
Thanks!

- Troy
>
>
> Regards
> Aurelien
>
> --
> Aurelien Jarno GPG: 4096R/1DDD8C9B
> aurelien@aurel32.net http://aurel32.net
>