local/pci: pci-exynos5433: Fix invalid GPIO accesses when of_get_named_gpio() fails

Before each use of GPIO (wlanen_gpio or reset_gpio) the driver compared
it to 0. But on error of_get_named_gpio() returns -ERRNO, not 0.
Actually 0 may be a valid GPIO.

If of_get_named_gpio() fails then fail the probe. Otherwise just work on
provided GPIO without further checks in the driver for its validity.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

diff --git a/drivers/pci/host/pci-exynos5433.c b/drivers/pci/host/pci-exynos5433.c
index 22a0c3c..9ebce33 100644 (file)
--- a/drivers/pci/host/pci-exynos5433.c
+++ b/drivers/pci/host/pci-exynos5433.c
@@ -420,12 +420,8 @@ static int exynos_pcie_wr_own_conf(struct pcie_port *pp, int where, int size,
 static int exynos_pcie_power_enabled(struct pcie_port *pp)
 {
        struct exynos_pcie *ep = to_exynos_pcie(pp);
-       int ret = 1;
 
-       if (ep->wlanen_gpio)
-               ret = gpio_get_value(ep->wlanen_gpio);
-
-       return ret;
+       return gpio_get_value(ep->wlanen_gpio);
 }
 
 static struct pcie_host_ops exynos_pcie_host_ops = {
@@ -455,7 +451,12 @@ static int __init exynos_pcie_probe(struct platform_device *pdev)
        pp->dev = &pdev->dev;
 
        exynos_pcie->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);
+       if (exynos_pcie->reset_gpio < 0)
+               return exynos_pcie->reset_gpio;
+
        exynos_pcie->wlanen_gpio = of_get_named_gpio(np, "wlanen-gpio", 0);
+       if (exynos_pcie->wlanen_gpio < 0)
+               return exynos_pcie->wlanen_gpio;
 
        exynos_pcie->clk = devm_clk_get(&pdev->dev, "pcie");
        if (IS_ERR(exynos_pcie->clk)) {
@@ -609,7 +610,7 @@ static int exynos_pcie_suspend_noirq(struct device *dev)
        struct exynos_pcie *ep = dev_get_drvdata(dev);
        u32 val, count = 0;
 
-       if (ep->wlanen_gpio && !gpio_get_value(ep->wlanen_gpio))
+       if (!gpio_get_value(ep->wlanen_gpio))
                return 0;
 
        exynos_pcie_writel(ep->elbi_base, VEN_MSG_REQ_DISABLE,
@@ -657,7 +658,7 @@ static int exynos_pcie_resume_noirq(struct device *dev)
        struct pcie_port *pp = &ep->pp;
        u32 val;
 
-       if (ep->wlanen_gpio && !gpio_get_value(ep->wlanen_gpio)) {
+       if (!gpio_get_value(ep->wlanen_gpio)) {
                clk_prepare_enable(ep->clk);
                clk_prepare_enable(ep->bus_clk);