[PATCH v14 20/39] pwm: tegra: Add runtime PM and OPP support

[Dmitry Osipenko]

26.10.2021 01:40, Dmitry Osipenko пишет:
> +	ret = devm_pm_runtime_enable(&pdev->dev);
> +	if (ret)
> +		return ret;
> +
> +	ret = devm_tegra_core_dev_init_opp_table_common(&pdev->dev);
> +	if (ret)
> +		return ret;
> +
> +	ret = pm_runtime_resume_and_get(&pdev->dev);
> +	if (ret)
> +		return ret;
> +
>  	/* Set maximum frequency of the IP */
> -	ret = clk_set_rate(pwm->clk, pwm->soc->max_frequency);
> +	ret = dev_pm_opp_set_rate(pwm->dev, pwm->soc->max_frequency);
>  	if (ret < 0) {
>  		dev_err(&pdev->dev, "Failed to set max frequency: %d\n", ret);
> -		return ret;
> +		goto put_pm;
>  	}
>  
>  	/*
> @@ -278,7 +294,7 @@ static int tegra_pwm_probe(struct platform_device *pdev)
>  	if (IS_ERR(pwm->rst)) {
>  		ret = PTR_ERR(pwm->rst);
>  		dev_err(&pdev->dev, "Reset control is not found: %d\n", ret);
> -		return ret;
> +		goto put_pm;
>  	}
>  
>  	reset_control_deassert(pwm->rst);
> @@ -291,10 +307,15 @@ static int tegra_pwm_probe(struct platform_device *pdev)
>  	if (ret < 0) {
>  		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
>  		reset_control_assert(pwm->rst);
> -		return ret;
> +		goto put_pm;
>  	}
>  
> +	pm_runtime_put(&pdev->dev);
> +
>  	return 0;
> +put_pm:
> +	pm_runtime_put_sync_suspend(&pdev->dev);
> +	return ret;
>  }
>  
>  static int tegra_pwm_remove(struct platform_device *pdev)
> @@ -305,20 +326,44 @@ static int tegra_pwm_remove(struct platform_device *pdev)
>  
>  	reset_control_assert(pc->rst);
>  
> +	pm_runtime_force_suspend(&pdev->dev);

I just noticed that RPM core doesn't reset RPM-enable count of a device
on driver's unbind (pm_runtime_reinit). It was a bad idea to use
devm_pm_runtime_enable() + pm_runtime_force_suspend() here, since RPM is
disabled twice on driver's removal, and thus, RPM will never be enabled
again.

I'll fix it for PWM and other drivers in this series, in v15.