The calls to devm_gpiod_get_optional() have the -gpios at the end of
the name but the GPIO core code is already adding the suffix during
the lookup. This means the PCIe driver is not finding the necessary
reset or power lines to allow initialisation of the PCIe.
This bug has not been noticed as if U-Boot has setup the GPIO lines
for the hardware when it does the PCIe initialisation (either by
booting from PCIe or user command to access PCIe) then the PCIe
will work in Linux. The U-Boot as supplied by SiFive does not by
default initialise any PCIe component.
Signed-off-by: Ben Dooks <[email protected]>
---
drivers/pci/controller/dwc/pcie-fu740.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/controller/dwc/pcie-fu740.c b/drivers/pci/controller/dwc/pcie-fu740.c
index 00cde9a248b5..842b7202b96e 100644
--- a/drivers/pci/controller/dwc/pcie-fu740.c
+++ b/drivers/pci/controller/dwc/pcie-fu740.c
@@ -259,11 +259,11 @@ static int fu740_pcie_probe(struct platform_device *pdev)
return PTR_ERR(afp->mgmt_base);
/* Fetch GPIOs */
- afp->reset = devm_gpiod_get_optional(dev, "reset-gpios", GPIOD_OUT_LOW);
+ afp->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
if (IS_ERR(afp->reset))
return dev_err_probe(dev, PTR_ERR(afp->reset), "unable to get reset-gpios\n");
- afp->pwren = devm_gpiod_get_optional(dev, "pwren-gpios", GPIOD_OUT_LOW);
+ afp->pwren = devm_gpiod_get_optional(dev, "pwren", GPIOD_OUT_LOW);
if (IS_ERR(afp->pwren))
return dev_err_probe(dev, PTR_ERR(afp->pwren), "unable to get pwren-gpios\n");
--
2.34.1
On Mon, Feb 21, 2022 at 09:03:46PM +0000, Ben Dooks wrote:
> The calls to devm_gpiod_get_optional() have the -gpios at the end of
> the name but the GPIO core code is already adding the suffix during
> the lookup. This means the PCIe driver is not finding the necessary
> reset or power lines to allow initialisation of the PCIe.
>
> This bug has not been noticed as if U-Boot has setup the GPIO lines
> for the hardware when it does the PCIe initialisation (either by
> booting from PCIe or user command to access PCIe) then the PCIe
> will work in Linux. The U-Boot as supplied by SiFive does not by
> default initialise any PCIe component.
Lorenzo, if you apply this, would you mind s/fix/Fix/ in the subject?
Or maybe even update to "Drop redundant '-gpios' from DT GPIO lookup"?
> Signed-off-by: Ben Dooks <[email protected]>
> ---
> drivers/pci/controller/dwc/pcie-fu740.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-fu740.c b/drivers/pci/controller/dwc/pcie-fu740.c
> index 00cde9a248b5..842b7202b96e 100644
> --- a/drivers/pci/controller/dwc/pcie-fu740.c
> +++ b/drivers/pci/controller/dwc/pcie-fu740.c
> @@ -259,11 +259,11 @@ static int fu740_pcie_probe(struct platform_device *pdev)
> return PTR_ERR(afp->mgmt_base);
>
> /* Fetch GPIOs */
> - afp->reset = devm_gpiod_get_optional(dev, "reset-gpios", GPIOD_OUT_LOW);
> + afp->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
> if (IS_ERR(afp->reset))
> return dev_err_probe(dev, PTR_ERR(afp->reset), "unable to get reset-gpios\n");
>
> - afp->pwren = devm_gpiod_get_optional(dev, "pwren-gpios", GPIOD_OUT_LOW);
> + afp->pwren = devm_gpiod_get_optional(dev, "pwren", GPIOD_OUT_LOW);
> if (IS_ERR(afp->pwren))
> return dev_err_probe(dev, PTR_ERR(afp->pwren), "unable to get pwren-gpios\n");
>
> --
> 2.34.1
>