Re: [PATCH 5/8] tty: mps2-uart: Use devm_clk_get_enabled() helpers

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Thu, Aug 22, 2024 at 11:39:09AM +0800, Lei Liu wrote:
> The devm_clk_get_enabled() helpers:
>     - call devm_clk_get()
>     - call clk_prepare_enable() and register what is needed in order to
>      call clk_disable_unprepare() when needed, as a managed resource.
> 
> This simplifies the code and avoids calls to clk_disable_unprepare().

...

> -	mps_port->clk = devm_clk_get(&pdev->dev, NULL);
> +	mps_port->clk = devm_clk_get_enabled(&pdev->dev, NULL);
>  	if (IS_ERR(mps_port->clk))
>  		return PTR_ERR(mps_port->clk);
>  
> -	ret = clk_prepare_enable(mps_port->clk);
> -	if (ret)
> -		return ret;
> -
>  	mps_port->port.uartclk = clk_get_rate(mps_port->clk);
>  
> -	clk_disable_unprepare(mps_port->clk);

Your change is not equivalent. In case this clock is shared this may lead to
run-time issues. Hence I don't think this patch is needed in this case.
Instead, you may add a comment on top of devm_clk_get() to explain that we only
need it be enabled to get clock rate in the probe.

-- 
With Best Regards,
Andy Shevchenko