Commit 5c5fb40d authored by Petr Štetiar's avatar Petr Štetiar Committed by Bjorn Helgaas
Browse files

PCI: imx6: Add support for active-low reset GPIO 



We previously used of_get_named_gpio(), which ignores the OF flags cell, so
the reset GPIO defaulted to "active high." This doesn't work on the Toradex
Apalis SoM with Ixora base board, which has an active-low reset GPIO.

Use devm_gpiod_get_optional() instead so we pay attention to the active
high/low flag.  This also adds support for GPIOs described via ACPI.

[bhelgaas: changelog]
Signed-off-by: default avatarPetr Štetiar <ynezz@true.cz>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarLucas Stach <l.stach@pengutronix.de>
parent bd534e69

drivers/pci/host/pci-imx6.c

+6 −14
Original line number Diff line number Diff line
@@ -32,7 +32,7 @@ 
#define to_imx6_pcie(x)	container_of(x, struct imx6_pcie, pp)



struct imx6_pcie {

	int			reset_gpio;

	struct gpio_desc	*reset_gpio;

	struct clk		*pcie_bus;

	struct clk		*pcie_phy;

	struct clk		*pcie;
@@ -287,10 +287,10 @@ static int imx6_pcie_deassert_core_reset(struct pcie_port *pp) 
	usleep_range(200, 500);



	/* Some boards don't have PCIe reset GPIO. */

	if (gpio_is_valid(imx6_pcie->reset_gpio)) {

		gpio_set_value_cansleep(imx6_pcie->reset_gpio, 0);

	if (imx6_pcie->reset_gpio) {

		gpiod_set_value_cansleep(imx6_pcie->reset_gpio, 0);

		msleep(100);

		gpio_set_value_cansleep(imx6_pcie->reset_gpio, 1);

		gpiod_set_value_cansleep(imx6_pcie->reset_gpio, 1);

	}

	return 0;
@@ -560,7 +560,6 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) 
{

	struct imx6_pcie *imx6_pcie;

	struct pcie_port *pp;

	struct device_node *np = pdev->dev.of_node;

	struct resource *dbi_base;

	int ret;
@@ -581,15 +580,8 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) 
		return PTR_ERR(pp->dbi_base);



	/* Fetch GPIOs */

	imx6_pcie->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);

	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->reset_gpio = devm_gpiod_get_optional(&pdev->dev, "reset",

							GPIOD_OUT_LOW);



	/* Fetch clocks */

	imx6_pcie->pcie_phy = devm_clk_get(&pdev->dev, "pcie_phy");

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