Re: [PATCH v1 1/2] i2c:busses:Register PCI1XXXX adapter to I2C subsystem

[Andy Shevchenko]

On Thu, Oct 7, 2021 at 7:25 PM Dmitry Osipenko <digetx@xxxxxxxxx> wrote:
> 05.10.2021 11:50, LakshmiPraveen Kopparthi пишет:
> >> Why i2c->freq is fixed to I2C_MAX_FAST_MODE_FREQ in
> >> pci1xxxx_i2c_init()?
> > This is the default frequency at which the adapter shall operate. This
> > driver is targeted for x86,X64 platforms. Could you please suggest a
> > way to configure the freqeuncy?
>
> For x86 it should come somewhere from ACPI info presumably, but I'm not
> ACPI expert. Andy may have more insight.
>
> At least you could add a clarifying comment to the code, telling why
> freq is fixed to the standard speed.

Since it's a host controller adapter driver we have to choose
something it will operate by default. In ACPI the peripheral may ask
for higher or lower speed and in i2c_acpi_find_bus_speed() [1] we
decide at which speed it should be.

[1]: https://elixir.bootlin.com/linux/latest/source/drivers/i2c/i2c-core-acpi.c#L331

-- 
With Best Regards,
Andy Shevchenko