On Fri, Nov 27, 2015 at 11:56:34AM +0100, Petr Štetiar wrote:
> It's currently not possible to use reset-gpio on board where the GPIO is
> active low as the code incorrectly assumes, that reset-gpio will be
> always active high.
>
> In my case the broken behavior was observed on Toradex Apalis SoM with
> Ixora base board.
>
> Signed-off-by: Petr Štetiar <ynezz@xxxxxxx>
Applied as follows with Lucas' reviewed-by to pci/host-imx6 for v4.5,
thanks!
commit 5c5fb40de8f14391a1238db05cef88754faf9229
Author: Petr Štetiar <ynezz@xxxxxxx>
Date: Fri Nov 27 11:56:34 2015 +0100
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: Petr Štetiar <ynezz@xxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Reviewed-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
index 3c3b37f..8e9afa5 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 {
- 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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