Re: [PATCH v5 7/8] serial: qcom-geni: Enable PM runtime for serial driver

[Bryan O'Donoghue <bryan.odonoghue@linaro.org>]

On 06/05/2025 19:02, Praveen Talari wrote:
> Add Power Management (PM) runtime support to Qualcomm GENI
> serial driver.
> 
> Introduce necessary callbacks and updates to ensure seamless
> transitions between power states, enhancing overall power
> efficiency.
> 
> Signed-off-by: Praveen Talari <quic_ptalari@quicinc.com>
> ---
>   drivers/tty/serial/qcom_geni_serial.c | 33 +++++++++++++++++++++++----
>   1 file changed, 29 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
> index 60afee3884a6..9d698c354510 100644
> --- a/drivers/tty/serial/qcom_geni_serial.c
> +++ b/drivers/tty/serial/qcom_geni_serial.c
> @@ -1686,10 +1686,10 @@ static void qcom_geni_serial_pm(struct uart_port *uport,
>   		old_state = UART_PM_STATE_OFF;
> 
>   	if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF)
> -		geni_serial_resources_on(uport);
> +		pm_runtime_resume_and_get(uport->dev);
>   	else if (new_state == UART_PM_STATE_OFF &&
>   			old_state == UART_PM_STATE_ON)
> -		geni_serial_resources_off(uport);
> +		pm_runtime_put_sync(uport->dev);
> 
>   }
> 
> @@ -1827,9 +1827,11 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
>   		return ret;
>   	}
> 
> +	pm_runtime_enable(port->se.dev);
> +
>   	ret = uart_add_one_port(drv, uport);
>   	if (ret)
> -		return ret;
> +		goto error;
> 
>   	if (port->wakeup_irq > 0) {
>   		device_init_wakeup(&pdev->dev, true);
> @@ -1839,11 +1841,15 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
>   			device_init_wakeup(&pdev->dev, false);
>   			ida_free(&port_ida, uport->line);
>   			uart_remove_one_port(drv, uport);
> -			return ret;
> +			goto error;
>   		}
>   	}
> 
>   	return 0;
> +
> +error:
> +	pm_runtime_disable(port->se.dev);
> +	return ret;
>   }
> 
>   static void qcom_geni_serial_remove(struct platform_device *pdev)
> @@ -1855,9 +1861,26 @@ static void qcom_geni_serial_remove(struct platform_device *pdev)
>   	dev_pm_clear_wake_irq(&pdev->dev);
>   	device_init_wakeup(&pdev->dev, false);
>   	ida_free(&port_ida, uport->line);
> +	pm_runtime_disable(port->se.dev);
>   	uart_remove_one_port(drv, &port->uport);
>   }
> 
> +static int qcom_geni_serial_runtime_suspend(struct device *dev)
> +{
> +	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
> +	struct uart_port *uport = &port->uport;
> +
> +	return geni_serial_resources_off(uport);
> +};
> +
> +static int qcom_geni_serial_runtime_resume(struct device *dev)
> +{
> +	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
> +	struct uart_port *uport = &port->uport;
> +
> +	return geni_serial_resources_on(uport);
> +};
> +
>   static int qcom_geni_serial_suspend(struct device *dev)
>   {
>   	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
> @@ -1901,6 +1924,8 @@ static const struct qcom_geni_device_data qcom_geni_uart_data = {
>   };
> 
>   static const struct dev_pm_ops qcom_geni_serial_pm_ops = {
> +	SET_RUNTIME_PM_OPS(qcom_geni_serial_runtime_suspend,
> +			   qcom_geni_serial_runtime_resume, NULL)
>   	SYSTEM_SLEEP_PM_OPS(qcom_geni_serial_suspend, qcom_geni_serial_resume)
>   };
> 
> --
> 2.17.1
> 
> 
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>