Re: [PATCH V2 1/7] PCI: imx6: Make reset-gpio optional

[Bjorn Helgaas <bhelgaas@google.com>]

On Thu, Dec 12, 2013 at 10:49:58PM +0100, 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@denx.de>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Frank Li <lznuaa@gmail.com>
> Cc: Harro Haan <hrhaan@gmail.com>
> Cc: Jingoo Han <jg1.han@samsung.com>
> Cc: Mohit KUMAR <Mohit.KUMAR@st.com>
> Cc: Pratyush Anand <pratyush.anand@st.com>
> Cc: Richard Zhu <r65037@freescale.com>
> Cc: Sascha Hauer <s.hauer@pengutronix.de>
> Cc: Sean Cross <xobs@kosagi.com>
> Cc: Shawn Guo <shawn.guo@linaro.org>
> Cc: Siva Reddy Kallam <siva.kallam@samsung.com>
> Cc: Srikanth T Shivanand <ts.srikanth@samsung.com>
> Cc: Tim Harvey <tharvey@gateworks.com>
> Cc: Troy Kisky <troy.kisky@boundarydevices.com>
> Cc: Yinghai Lu <yinghai@kernel.org>
> ---
>  .../devicetree/bindings/pci/designware-pcie.txt    |  2 ++
>  drivers/pci/host/pci-imx6.c                        | 29 +++++++++++-----------
>  2 files changed, 17 insertions(+), 14 deletions(-)

Richard or Shawn, can you ack/nak these (patches 1-6)?  I'd like to dispose
of them one way or the other.

> 
> V2: Make the 'reset-gpio' prop shared between imx6 and exynos
>     Rebase on top of pci/host-imx6
> 
> diff --git a/Documentation/devicetree/bindings/pci/designware-pcie.txt b/Documentation/devicetree/bindings/pci/designware-pcie.txt
> index d5d26d4..d6fae13 100644
> --- a/Documentation/devicetree/bindings/pci/designware-pcie.txt
> +++ b/Documentation/devicetree/bindings/pci/designware-pcie.txt
> @@ -19,6 +19,8 @@ Required properties:
>  	to define the mapping of the PCIe interface to interrupt
>  	numbers.
>  - num-lanes: number of lanes to use
> +
> +Optional properties:
>  - reset-gpio: gpio pin number of power good signal
>  
>  Optional properties for fsl,imx6q-pcie
> diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
> index 9fc1cb6..c247602 100644
> --- a/drivers/pci/host/pci-imx6.c
> +++ b/drivers/pci/host/pci-imx6.c
> @@ -214,9 +214,12 @@ 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;
>  }
> @@ -432,17 +435,15 @@ 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;
> -	}
> -	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");
> -		return ret;
> +	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");
> +			return ret;
> +		}
>  	}
>  
>  	imx6_pcie->power_on_gpio = of_get_named_gpio(np, "power-on-gpio", 0);
> -- 
> 1.8.4.3
>