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

[Aniket RANDIVE]

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.

Thanks,
Aniket

> > +    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 */
> > +
>
> [...]