[PATCH V5 2/4] PCI: imx6: Add skip_pwrctrl_off flag support

Frank Li Frank.li at oss.nxp.com
Thu Jul 9 07:53:57 PDT 2026


On Thu, Jul 09, 2026 at 06:15:53PM +0800, Sherry Sun (OSS) wrote:
> From: Sherry Sun <sherry.sun at nxp.com>
>
> Use dw_pcie_rp::skip_pwrctrl_off to avoid powering off devices during
> suspend to preserve wakeup capability of the devices and also not to
> power on the devices in the init path.
>
> This allows controller power-off to be skipped when some devices (e.g.
> M.2 Key E cards without auxiliary power) need to support PCIe L2 link
> state and wake-up mechanisms.
>
> Signed-off-by: Sherry Sun <sherry.sun at nxp.com>
> ---
>  drivers/pci/controller/dwc/pci-imx6.c | 16 ++++++++++------
>  1 file changed, 10 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 92f8e4a299e8..afcf3b6bf3cd 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -1382,10 +1382,12 @@ static int imx_pcie_host_init(struct dw_pcie_rp *pp)
>  		}
>  	}
>
> -	ret = pci_pwrctrl_power_on_devices(dev);
> -	if (ret) {
> -		dev_err(dev, "failed to power on pwrctrl devices\n");
> -		goto err_reg_disable;
> +	if (!pp->skip_pwrctrl_off) {

if pci_pwrctrl_power_on_devices is true, where call pci_pwrctrl_power_on_devices()

> +		ret = pci_pwrctrl_power_on_devices(dev);
> +		if (ret) {
> +			dev_err(dev, "failed to power on pwrctrl devices\n");
> +			goto err_reg_disable;
> +		}
>  	}
>
>  	ret = imx_pcie_clk_enable(imx_pcie);
> @@ -1454,7 +1456,8 @@ static int imx_pcie_host_init(struct dw_pcie_rp *pp)
>  err_clk_disable:
>  	imx_pcie_clk_disable(imx_pcie);
>  err_pwrctrl_power_off:
> -	pci_pwrctrl_power_off_devices(dev);
> +	if (!pp->skip_pwrctrl_off)
> +		pci_pwrctrl_power_off_devices(dev);
>  err_reg_disable:
>  	if (imx_pcie->vpcie)
>  		regulator_disable(imx_pcie->vpcie);
> @@ -1473,7 +1476,8 @@ static void imx_pcie_host_exit(struct dw_pcie_rp *pp)
>  	}
>  	imx_pcie_clk_disable(imx_pcie);
>
> -	pci_pwrctrl_power_off_devices(pci->dev);
> +	if (!pci->pp.skip_pwrctrl_off)
> +		pci_pwrctrl_power_off_devices(pci->dev);

Not sure if there are counter in side power_(on|off) function, if not,
just skip power_off is enough.

Frank

>  	if (imx_pcie->vpcie)
>  		regulator_disable(imx_pcie->vpcie);
>  }
> --
> 2.50.1
>
>



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