[PATCH] spi: rockchip: Avoid redundant clock disable in pm operation

[Kuan-Wei Chiu]

Hi Jon,

On Sat, Aug 24, 2024 at 12:57:02PM +0800, Jon Lin wrote:
> Fix WARN_ON:
> [   22.869352][ T1885] clk_spi0 already unprepared
> [   22.869379][ T1885] WARNING: CPU: 3 PID: 1885 at drivers/clk/clk.c:813 clk_core_unprepare+0xbc4
> [   22.869380][ T1885] Modules linked in: bcmdhd dhd_static_buf
> [   22.869391][ T1885] CPU: 3 PID: 1885 Comm: Binder:355_2 Tainted: G        W         5.10.66 #59
> [   22.869393][ T1885] Hardware name: Rockchip RK3588 EVB1 LP4 V10 Board (DT)
> [   22.869397][ T1885] pstate: 60400009 (nZCv daif +PAN -UAO -TCO BTYPE=--)
> [   22.869401][ T1885] pc : clk_core_unprepare+0xbc/0x214
> [   22.869404][ T1885] lr : clk_core_unprepare+0xbc/0x214
> 
> Fixes:  ("spi: rockchip: Suspend and resume the bus during NOIRQ_SYSTEM_SLEEP_PM ops")

Thanks for the patch. However, the fixes tag should include the 12
characters of SHA-1 ID. the corrected Fixes tag should be:

Fixes: e882575efc77 ("spi: rockchip: Suspend and resume the bus during NOIRQ_SYSTEM_SLEEP_PM ops")

Regards,
Kuan-Wei

> Signed-off-by: Jon Lin <jon.lin at rock-chips.com>
> ---
> 
>  drivers/spi/spi-rockchip.c | 57 +++++++++++++++++---------------------
>  1 file changed, 26 insertions(+), 31 deletions(-)
> 
> diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
> index e1ecd96c7858..043a7739c330 100644
> --- a/drivers/spi/spi-rockchip.c
> +++ b/drivers/spi/spi-rockchip.c
> @@ -940,33 +940,24 @@ static void rockchip_spi_remove(struct platform_device *pdev)
>  	spi_controller_put(ctlr);
>  }
>  
> -#ifdef CONFIG_PM_SLEEP
> -static int rockchip_spi_suspend(struct device *dev)
> +#ifdef CONFIG_PM
> +static int rockchip_spi_runtime_suspend(struct device *dev)
>  {
> -	int ret;
>  	struct spi_controller *ctlr = dev_get_drvdata(dev);
>  	struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
>  
> -	ret = spi_controller_suspend(ctlr);
> -	if (ret < 0)
> -		return ret;
> -
>  	clk_disable_unprepare(rs->spiclk);
>  	clk_disable_unprepare(rs->apb_pclk);
>  
> -	pinctrl_pm_select_sleep_state(dev);
> -
>  	return 0;
>  }
>  
> -static int rockchip_spi_resume(struct device *dev)
> +static int rockchip_spi_runtime_resume(struct device *dev)
>  {
>  	int ret;
>  	struct spi_controller *ctlr = dev_get_drvdata(dev);
>  	struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
>  
> -	pinctrl_pm_select_default_state(dev);
> -
>  	ret = clk_prepare_enable(rs->apb_pclk);
>  	if (ret < 0)
>  		return ret;
> @@ -975,41 +966,45 @@ static int rockchip_spi_resume(struct device *dev)
>  	if (ret < 0)
>  		clk_disable_unprepare(rs->apb_pclk);
>  
> -	ret = spi_controller_resume(ctlr);
> -	if (ret < 0) {
> -		clk_disable_unprepare(rs->spiclk);
> -		clk_disable_unprepare(rs->apb_pclk);
> -	}
> -
>  	return 0;
>  }
> -#endif /* CONFIG_PM_SLEEP */
> +#endif /* CONFIG_PM */
>  
> -#ifdef CONFIG_PM
> -static int rockchip_spi_runtime_suspend(struct device *dev)
> +#ifdef CONFIG_PM_SLEEP
> +static int rockchip_spi_suspend(struct device *dev)
>  {
> +	int ret;
>  	struct spi_controller *ctlr = dev_get_drvdata(dev);
> -	struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
>  
> -	clk_disable_unprepare(rs->spiclk);
> -	clk_disable_unprepare(rs->apb_pclk);
> +	ret = spi_controller_suspend(ctlr);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* Avoid redundant clock disable */
> +	if (!pm_runtime_status_suspended(dev))
> +		rockchip_spi_runtime_suspend(dev);
> +
> +	pinctrl_pm_select_sleep_state(dev);
>  
>  	return 0;
>  }
>  
> -static int rockchip_spi_runtime_resume(struct device *dev)
> +static int rockchip_spi_resume(struct device *dev)
>  {
>  	int ret;
>  	struct spi_controller *ctlr = dev_get_drvdata(dev);
> -	struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
>  
> -	ret = clk_prepare_enable(rs->apb_pclk);
> -	if (ret < 0)
> -		return ret;
> +	pinctrl_pm_select_default_state(dev);
>  
> -	ret = clk_prepare_enable(rs->spiclk);
> +	if (!pm_runtime_status_suspended(dev)) {
> +		ret = rockchip_spi_runtime_resume(dev);
> +		if (ret < 0)
> +			return ret;
> +	}
> +
> +	ret = spi_controller_resume(ctlr);
>  	if (ret < 0)
> -		clk_disable_unprepare(rs->apb_pclk);
> +		rockchip_spi_runtime_suspend(dev);
>  
>  	return 0;
>  }
> -- 
> 2.34.1
> 
>