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

On Saturday, October 12, 2013 6:29 PM, Marek Vasut wrote:

quoted

On Fri, Oct 11, 2013 at 04:12:31AM +0200, Marek Vasut wrote:

quoted

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 <redacted>
Cc: Richard Zhu <redacted>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Sean Cross <redacted>
Cc: Shawn Guo <redacted>
Cc: Tim Harvey <tharvey@gateworks.com>
Cc: Yinghai Lu <yinghai@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.

That's true, thanks for pointing it out!

+cc Kishon Vijay Abraham I, Pratyush Anand, Mohit KUMAR

Yes, right.
"reset-gpio" property can be moved to an optional property.
Also, the patch to fix 'Designware' part such as 'designware-pcie.txt'
can be shared with other related people as below.

  - Samsung Exynos PCIe: Jingoo Han
  - ST Spear PCIe: Pratyush Anand, Mohit KUMAR
  - TI OMAP PCIe: Kishon Vijay Abraham I

Best regards,
Jingoo Han