Re: [PATCH v7 1/2] i2c: core: Add i2c_update_timeout() helper for dynamic transfer timeouts

[Aniket RANDIVE]

On 8/24/2026 7:14 PM, Mukesh Savaliya wrote:
> On 8/24/2026 3:36 PM, Aniket RANDIVE wrote:
> > On 8/24/2026 11:49 AM, Mukesh Savaliya wrote:
> > > On 8/13/2026 11:15 AM, Aniket Randive wrote:
> > > [...]
> > >
> > > > +void i2c_update_timeout(struct i2c_adapter *adap, u32 bus_freq_hz,
> > > > +            size_t len, unsigned int safety_coeff,
> > > > +            unsigned int min_usec)
> > > > +{
> > > > +    u64 bit_usec = mul_u64_u32_div(len * 9, USEC_PER_SEC, 
> > > > bus_freq_hz);
> > > let's validate bus_freq_hz to prevent from 0 value in case of any 
> > > abnormal caller.
> >
> > This scenario is highly unlikely. Most drivers operate with a default 
> > bus frequency, typically 400 kHz, and therefore the condition being 
> > checked is not expected to occur in practice. As a result, I do not 
> > believe this validation is necessary in this case.
>
> Unlikely but also possible, it's framework change. So can't guarantee 
> about all other soc drivers.

Sure. I will provide a warning and return early if frequency is 0.

> > Thanks,
> > Aniket
>
> Please remove this sign from in between.
>
> > > > +    u64 total_usec = bit_usec * safety_coeff + min_usec;
> > > > +    unsigned long jiffies_val;
> > > > +
> > > > +    /* Userspace-configured timeout always takes precedence. */
> > > > +    if (adap->user_timeout > 0) {
> > > > +        adap->timeout = adap->user_timeout;
> > > > +        return;
> > > > +    }
> > > > +
> > > > +    jiffies_val = usecs_to_jiffies((unsigned int)min_t(u64, 
> > > > total_usec, UINT_MAX));
> > > > +    /* adap->timeout is int; guard against signed overflow. */
> > > > +    adap->timeout = (int)min_t(unsigned long, jiffies_val, INT_MAX);
> > > > +}
> > > > +EXPORT_SYMBOL_GPL(i2c_update_timeout);
> > > > +#endif /* CONFIG_I2C_DYNAMIC_TIMEOUT */
> > > > +
> > >
> > > [...]