[PATCH 1/2] PCI: imx6: Make reset-gpio optional

[Shawn Guo]

On Fri, Oct 11, 2013 at 04:12:31AM +0200, Marek Vasut wrote:
> Some boards do not have a PCIe reset GPIO. To avoid probe
> failure on these boards, make the reset GPIO optional as
> well.
> 
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Bjorn Helgaas <bhelgaas at google.com>
> Cc: Frank Li <lznuaa at gmail.com>
> Cc: Richard Zhu <r65037 at freescale.com>
> Cc: Sascha Hauer <s.hauer at pengutronix.de>
> Cc: Sean Cross <xobs at kosagi.com>
> Cc: Shawn Guo <shawn.guo at linaro.org>
> Cc: Tim Harvey <tharvey at gateworks.com>
> Cc: Yinghai Lu <yinghai at kernel.org>
> ---
>  drivers/pci/host/pci-imx6.c | 29 +++++++++++++++--------------
>  1 file changed, 15 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
> index d3639aa..8e7adce 100644
> --- a/drivers/pci/host/pci-imx6.c
> +++ b/drivers/pci/host/pci-imx6.c
> @@ -220,9 +220,12 @@ static int imx6_pcie_assert_core_reset(struct pcie_port *pp)
>  	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
>  			IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16);
>  
> -	gpio_set_value(imx6_pcie->reset_gpio, 0);
> -	msleep(100);
> -	gpio_set_value(imx6_pcie->reset_gpio, 1);
> +	/* Some boards don't have PCIe reset GPIO. */
> +	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
> +		gpio_set_value(imx6_pcie->reset_gpio, 0);
> +		msleep(100);
> +		gpio_set_value(imx6_pcie->reset_gpio, 1);
> +	}
>  
>  	return 0;
>  }
> @@ -447,17 +450,15 @@ static int __init imx6_pcie_probe(struct platform_device *pdev)
>  
>  	/* Fetch GPIOs */
>  	imx6_pcie->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);
> -	if (!gpio_is_valid(imx6_pcie->reset_gpio)) {
> -		dev_err(&pdev->dev, "no reset-gpio defined\n");
> -		ret = -ENODEV;
> -	}

The 'reset-gpio' is documented as a required property in bindings doc
Documentation/devicetree/bindings/pci/designware-pcie.txt.  You need
to update bindings doc if you turn it into an optional property.

Shawn

> -	ret = devm_gpio_request_one(&pdev->dev,
> -				imx6_pcie->reset_gpio,
> -				GPIOF_OUT_INIT_LOW,
> -				"PCIe reset");
> -	if (ret) {
> -		dev_err(&pdev->dev, "unable to get reset gpio\n");
> -		goto err;
> +	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
> +		ret = devm_gpio_request_one(&pdev->dev,
> +					imx6_pcie->reset_gpio,
> +					GPIOF_OUT_INIT_LOW,
> +					"PCIe reset");
> +		if (ret) {
> +			dev_err(&pdev->dev, "unable to get reset gpio\n");
> +			goto err;
> +		}
>  	}
>  
>  	imx6_pcie->power_on_gpio = of_get_named_gpio(np, "power-on-gpio", 0);
> -- 
> 1.8.4.rc3
>