Commit b2d7a9cd authored by Fabio Estevam's avatar Fabio Estevam Committed by Bjorn Helgaas
Browse files

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



Commit 5c5fb40d ("PCI: imx6: Add support for active-low reset GPIO")
cause regressions on some boards like MX6 Gateworks Ventana, for example.

The reason for the breakage is that this commit sets the GPIO polarity in
the wrong logic level.

Also, the commit log is wrong because active-low reset GPIO is what the
driver used to support since the beginning.

So keep the old behavior that ignores the GPIO polarity specified in the
device tree and treat the PCI reset GPIO as active-low.

Reported-by: default avatarKrzysztof Hałasa <khalasa@piap.pl>
Tested-by: Tim Harvey <tharvey@gateworks.com>	# Gateworks Ventana
Signed-off-by: default avatarFabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Acked-by: default avatarTim Harvey <tharvey@gateworks.com>
Acked-by: default avatarLucas Stach <l.stach@pengutronix.de>
CC: stable@vger.kernel.org	# v4.5+
parent 9735a227

drivers/pci/host/pci-imx6.c

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

#define to_imx6_pcie(x)	container_of(x, struct imx6_pcie, pp)





struct imx6_pcie {

struct imx6_pcie {

	struct gpio_desc	*reset_gpio;

	int			reset_gpio;

	struct clk		*pcie_bus;

	struct clk		*pcie_bus;

	struct clk		*pcie_phy;

	struct clk		*pcie_phy;

	struct clk		*pcie;

	struct clk		*pcie;
@@ -309,10 +309,10 @@ static int imx6_pcie_deassert_core_reset(struct pcie_port *pp) 
	usleep_range(200, 500);

	usleep_range(200, 500);





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

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

	if (imx6_pcie->reset_gpio) {

	if (gpio_is_valid(imx6_pcie->reset_gpio)) {

		gpiod_set_value_cansleep(imx6_pcie->reset_gpio, 0);

		gpio_set_value_cansleep(imx6_pcie->reset_gpio, 0);

		msleep(100);

		msleep(100);

		gpiod_set_value_cansleep(imx6_pcie->reset_gpio, 1);

		gpio_set_value_cansleep(imx6_pcie->reset_gpio, 1);

	}

	}

	return 0;

	return 0;
@@ -523,6 +523,7 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) 
{

{

	struct imx6_pcie *imx6_pcie;

	struct imx6_pcie *imx6_pcie;

	struct pcie_port *pp;

	struct pcie_port *pp;

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

	struct resource *dbi_base;

	struct resource *dbi_base;

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

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

	int ret;

	int ret;
@@ -544,8 +545,15 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) 
		return PTR_ERR(pp->dbi_base);

		return PTR_ERR(pp->dbi_base);





	/* Fetch GPIOs */

	/* Fetch GPIOs */

	imx6_pcie->reset_gpio = devm_gpiod_get_optional(&pdev->dev, "reset",

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

							GPIOD_OUT_LOW);

	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;

		}

	}





	/* Fetch clocks */

	/* Fetch clocks */

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

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

CRA Git | Maintained and supported by SUSTech CRA and CCSE