Re: [PATCH v7 3/5] iio: adc: versal-sysmon: add I2C driver

[Erim, Salih]

Hi Andy,

On 15/06/2026 15:30, Andy Shevchenko wrote:
> On Mon, Jun 15, 2026 at 12:37:20AM +0100, Salih Erim wrote:
> > Add an I2C transport driver for the Versal SysMon block. The SysMon
> > provides an I2C slave interface that allows an external master to
> > read voltage and temperature measurements through the same register
> > map used by the MMIO path.
> >
> > The I2C command frame is an 8-byte structure containing a 4-byte data
> > payload, a 2-byte register offset, and a 1-byte instruction field.
> > Read operations send the frame with a read instruction, then receive
> > a 4-byte response containing the register value.
> >
> > Events are not supported on the I2C path because there is no
> > interrupt line and the I2C regmap backend cannot be called from
> > atomic context.
>
> ...
>
> > +static const struct regmap_config sysmon_i2c_regmap_config = {
> > +     .reg_bits = 32,
> > +     .val_bits = 32,
> > +     .reg_stride = SYSMON_REG_STRIDE,
> > +     .max_register = SYSMON_MAX_REG,
> > +     .reg_read = sysmon_i2c_reg_read,
> > +     .reg_write = sysmon_i2c_reg_write,
> > +};
>
> No cache?

No, the registers are live ADC readings and interrupt status.
Caching would return stale voltage and temperature data.

Thanks,
Salih

> --
> With Best Regards,
> Andy Shevchenko