Re: [PATCH v3 3/4] soc: qcom: geni-se: Do not keep GPIOs to sleep state for shared SE usecase

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 27.09.2024 8:31 AM, Mukesh Kumar Savaliya wrote:
> Currently the driver provides a function called geni_serial_resources_off()
> to turn off resources like clocks and  pinctrl.
> 
> For shared SE between two SS, we don't need to keep pinctrl to sleep state
> as other SS may be actively transferring data over SE. Hence,bypass keeping
> pinctrl to sleep state conditionally using shared_geni_se flag.
> 
> Signed-off-by: Mukesh Kumar Savaliya <quic_msavaliy@quicinc.com>
> ---
>  drivers/soc/qcom/qcom-geni-se.c  | 14 ++++++++++----
>  include/linux/soc/qcom/geni-se.h |  3 +++
>  2 files changed, 13 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/soc/qcom/qcom-geni-se.c b/drivers/soc/qcom/qcom-geni-se.c
> index 2e8f24d5da80..89cf18699336 100644
> --- a/drivers/soc/qcom/qcom-geni-se.c
> +++ b/drivers/soc/qcom/qcom-geni-se.c
> @@ -1,5 +1,6 @@
>  // SPDX-License-Identifier: GPL-2.0
>  // Copyright (c) 2017-2018, The Linux Foundation. All rights reserved.
> +// Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
>  
>  /* Disable MMIO tracing to prevent excessive logging of unwanted MMIO traces */
>  #define __DISABLE_TRACE_MMIO__
> @@ -503,10 +504,15 @@ int geni_se_resources_off(struct geni_se *se)
>  
>  	if (has_acpi_companion(se->dev))
>  		return 0;
> -
> -	ret = pinctrl_pm_select_sleep_state(se->dev);
> -	if (ret)
> -		return ret;
> +	/* Keep pinctrl to sleep state only for regular usecase.
> +	 * Do not sleep pinctrl for shared SE because other SS(subsystems)
> +	 * may continueto perform transfer.
> +	 */

/*
 * Don't alter pin states on shared SEs to avoid potentially
 * interrupting transfers started by other subsystems
 */


> +	if (se->shared_geni_se == false) {

if (!se->shared_geni_se)

> +		ret = pinctrl_pm_select_sleep_state(se->dev);
> +		if (ret)
> +			return ret;
> +	}
>  
>  	geni_se_clks_off(se);

Should the clocks be turned off?

Konrad