Re: [PATCH v1 3/4] soc: qcom: geni-se: Export function geni_se_clks_off()

Bryan O'Donoghue
2024-08-29T10:19:17Z

On 29/08/2024 10:24, Mukesh Kumar Savaliya wrote:
> Currently driver provides geni_se_resources_off() function to turn
> off SE resources like clocks, pinctrl. But we don't have function to
> control clock separately, hence export function geni_se_clks_off()
> to turn off clocks separately without disturbing GPIO.
>
> The client drivers like i2c requires this function for use case where
> i2c SE is shared between two subsystems.
>
> Signed-off-by: Mukesh Kumar Savaliya <quic_msavaliy@quicinc.com>

Suggest:

Currently the driver provides a function called
geni_serial_resources_off() to turn off resources like clocks and
pinctrl. We don't have a function to control clocks separately hence,
export the function geni_se_clks_off() to turn off clocks separately
without disturbing GPIO.

Client drivers like I2C require this function for use-cases where the
I2C SE is shared between two subsystems.

> ---
> drivers/soc/qcom/qcom-geni-se.c | 4 +++-
> include/linux/soc/qcom/geni-se.h | 3 +++
> 2 files changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/soc/qcom/qcom-geni-se.c b/drivers/soc/qcom/qcom-geni-se.c
> index 2e8f24d5da80..20166c8fc919 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__
> @@ -482,13 +483,14 @@ void geni_se_config_packing(struct geni_se *se, int bpw, int pack_words,
> }
> EXPORT_SYMBOL_GPL(geni_se_config_packing);
>
> -static void geni_se_clks_off(struct geni_se *se)
> +void geni_se_clks_off(struct geni_se *se)
> {
> struct geni_wrapper *wrapper = se->wrapper;
>
> clk_disable_unprepare(se->clk);
> clk_bulk_disable_unprepare(wrapper->num_clks, wrapper->clks);
> }
> +EXPORT_SYMBOL_GPL(geni_se_clks_off);
>

Does it make sense to have geni_se_clks_off() exported without having
geni_se_clks_on() similarly exported ?

Two exported functions already appear to wrapper this functionality for you.

geni_se_resources_off -> gensi_se_clks_off
geni_se_resources_on -> gensi_se_clks_on

Seems like a usage violation to have geni_se_resources_on() switch the
clocks on but then have something else directly call gensi_se_clks_off()
without going through geni_se_resources_off();

?

---
bod