[PATCH v2] Revert "PCI: imx6: Add support for active-low reset GPIO"

[Fabio Estevam <festevam@gmail.com>]

From: Fabio Estevam <fabio.estevam@nxp.com>

Commit 5c5fb40de8f14 ("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.

Cc: <stable@vger.kernel.org> # 4.5
Reported-by: Krzysztof Hałasa <khalasa@piap.pl>
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
---
Changes since v1:
- Improve wording of commit log (Tim)

 drivers/pci/host/pci-imx6.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
index eb5a275..2f817fa 100644
--- a/drivers/pci/host/pci-imx6.c
+++ b/drivers/pci/host/pci-imx6.c
@@ -32,7 +32,7 @@
 #define to_imx6_pcie(x)	container_of(x, struct imx6_pcie, pp)
 
 struct imx6_pcie {
-	struct gpio_desc	*reset_gpio;
+	int			reset_gpio;
 	struct clk		*pcie_bus;
 	struct clk		*pcie_phy;
 	struct clk		*pcie;
@@ -309,10 +309,10 @@ static int imx6_pcie_deassert_core_reset(struct pcie_port *pp)
 	usleep_range(200, 500);
 
 	/* Some boards don't have PCIe reset GPIO. */
-	if (imx6_pcie->reset_gpio) {
-		gpiod_set_value_cansleep(imx6_pcie->reset_gpio, 0);
+	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
+		gpio_set_value_cansleep(imx6_pcie->reset_gpio, 0);
 		msleep(100);
-		gpiod_set_value_cansleep(imx6_pcie->reset_gpio, 1);
+		gpio_set_value_cansleep(imx6_pcie->reset_gpio, 1);
 	}
 	return 0;
 
@@ -523,6 +523,7 @@ 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;
 	struct device_node *node = pdev->dev.of_node;
 	int ret;
@@ -544,8 +545,15 @@ static int __init imx6_pcie_probe(struct platform_device *pdev)
 		return PTR_ERR(pp->dbi_base);
 
 	/* Fetch GPIOs */
-	imx6_pcie->reset_gpio = devm_gpiod_get_optional(&pdev->dev, "reset",
-							GPIOD_OUT_LOW);
+	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;
+		}
+	}
 
 	/* Fetch clocks */
 	imx6_pcie->pcie_phy = devm_clk_get(&pdev->dev, "pcie_phy");
-- 
1.9.1