Re: [PATCH v4 1/2] soundwire: qcom: Add flag for software clock gating check

[Srinivasa Rao Mandadapu]

On 6/9/2022 8:52 PM, Pierre-Louis Bossart wrote:
Thanks for your time Pierre-Louis!!!
> On 6/9/22 09:30, Srinivasa Rao Mandadapu wrote:
> > Validate software clock gating required or not and do software
> > clock gating on hclk if soundwire is operational and keep it
> > running by adding flag in private data structure.
> > This is to avoid conflict between older architectures,
> > where software clock gating is not required and on latest
> > architectues, where software clock gating is mandatory.
> architectures.
Okay. Will fix it.
> > Signed-off-by: Srinivasa Rao Mandadapu <quic_srivasam@xxxxxxxxxxx>
> > Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
> > ---
> >   drivers/soundwire/qcom.c | 14 ++++++++++----
> >   1 file changed, 10 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c
> > index a3fccf0..8e163da 100644
> > --- a/drivers/soundwire/qcom.c
> > +++ b/drivers/soundwire/qcom.c
> > @@ -181,6 +181,7 @@ struct qcom_swrm_ctrl {
> >   struct qcom_swrm_data {
> >   	u32 default_cols;
> >   	u32 default_rows;
> > +	bool sw_clk_gate_required;
> >   };
> >   
> >   static const struct qcom_swrm_data swrm_v1_3_data = {
> > @@ -1311,6 +1312,15 @@ static int qcom_swrm_probe(struct platform_device *pdev)
> >   			return PTR_ERR(ctrl->mmio);
> >   	}
> >   
> > +	if (data->sw_clk_gate_required) {
> > +		ctrl->audio_cgcr = devm_reset_control_get_exclusive(dev, "swr_audio_cgcr");
> > +		if (IS_ERR(ctrl->audio_cgcr)) {
> You need to handle the NULL case, devm_reset_control_get_exclusive() can
> return ERR_OR_NULL
>
> https://elixir.bootlin.com/linux/latest/source/drivers/reset/core.c#L1045
Okay. Will change accordingly.
> > +			dev_err(dev, "Failed to get cgcr reset ctrl required for SW gating\n");
> > +			ret = PTR_ERR(ctrl->audio_cgcr);
> > +			goto err_init;
> > +		}
> > +	}
> > +
> >   	ctrl->irq = of_irq_get(dev->of_node, 0);
> >   	if (ctrl->irq < 0) {
> >   		ret = ctrl->irq;
> > @@ -1336,10 +1346,6 @@ static int qcom_swrm_probe(struct platform_device *pdev)
> >   	ctrl->bus.compute_params = &qcom_swrm_compute_params;
> >   	ctrl->bus.clk_stop_timeout = 300;
> >   
> > -	ctrl->audio_cgcr = devm_reset_control_get_exclusive(dev, "swr_audio_cgcr");
> > -	if (IS_ERR(ctrl->audio_cgcr))
> > -		dev_err(dev, "Failed to get audio_cgcr reset required for soundwire-v1.6.0\n");
> > -
> >   	ret = qcom_swrm_get_port_config(ctrl);
> >   	if (ret)
> >   		goto err_clk;