On Mon, Mar 28, 2016 at 2:45 PM, Fabio Estevam <festevam@xxxxxxxxx> wrote: > From: Fabio Estevam <fabio.estevam@xxxxxxx> > > 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@xxxxxxxxxxxxxxx> # 4.5 > Reported-by: Krzysztof Hałasa <khalasa@xxxxxxx> > Signed-off-by: Fabio Estevam <fabio.estevam@xxxxxxx> > --- > 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 > Fabio/Krzysztof - thanks for finding this regression that breaks PCI on most IMX6. I verified reverting this resolves Gateworks Ventana PCI breakage in v4.5. Acked-by: Tim Harvey <tharvey@xxxxxxxxxxxxx> Regards, Tim -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html