Re: [PATCH v8 4/4] i2c: qcom-geni: Support multi-owner controllers in GPI mode

[Mukesh Savaliya]

On 7/15/2026 5:54 PM, Konrad Dybcio wrote:
> On 7/8/26 7:10 AM, Mukesh Kumar Savaliya wrote:
> > Some platforms use a QUP-based I2C controller in a configuration where the
> > controller is shared with another system processor. In this setup the
> > operating system must not assume exclusive ownership of the controller or
> > its associated pins.
> >
> > Add support for enabling multi-owner operation when DeviceTree specifies
> > qcom,qup-multi-owner. When enabled, mark the underlying serial engine as
> > shared so the common GENI resource handling avoids selecting the "sleep"
> > pinctrl state, which could disrupt transfers initiated by the other
> > processor.
> >
> > For GPI mode transfers, request lock/unlock TRE sequencing from the GPI
> > driver by setting a single lock_action selector per message, emitting lock
> > before the first message and unlock after the last message (handling the
> > single-message case as well). This serializes access to the shared
> > controller without requiring message-position flags to be passed into the
> > DMA engine layer.
> >
> > Signed-off-by: Mukesh Kumar Savaliya <mukesh.savaliya@xxxxxxxxxxxxxxxx>
> > ---
>
> [...]
>
>
> > +		if (gi2c->se.multi_owner)
> > +			return dev_err_probe(gi2c->se.dev, -EINVAL,
> > +					     "I2C sharing not supported in non GSI mode\n");
>
> ultra nit: "non-GSI"
Will update in next patch.
> > +
> >   		tx_depth = geni_se_get_tx_fifo_depth(&gi2c->se);
> >   
> >   		/* I2C Master Hub Serial Elements doesn't have the HW_PARAM_0 register */
> > @@ -1098,6 +1115,11 @@ static int geni_i2c_probe(struct platform_device *pdev)
> >   		gi2c->clk_freq_out = I2C_MAX_STANDARD_MODE_FREQ;
> >   	}
> >   
> > +	if (of_property_read_bool(pdev->dev.of_node, "qcom,qup-multi-owner")) {
>
> Let's use device_property_present() instead.
Sure, Thanks for the suggestion and review. Will update in next patch.
> with that:
>
> Reviewed-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxxxx>
>
> Konrad