Re: [PATCH v2 1/4] PCI: rockchip: Make 'ep-gpios' DT property optional

On Sat, Dec 12, 2020 at 9:18 AM Chen-Yu Tsai [off-list ref] wrote:

On Mon, Dec 7, 2020 at 10:11 PM Rob Herring [off-list ref] wrote:

quoted

On Wed, Nov 18, 2020 at 1:17 AM Chen-Yu Tsai [off-list ref] wrote:

quoted

From: Chen-Yu Tsai <redacted>

The Rockchip PCIe controller DT binding clearly states that 'ep-gpios' is
an optional property. And indeed there are boards that don't require it.

Make the driver follow the binding by using devm_gpiod_get_optional()
instead of devm_gpiod_get().

Fixes: e77f847df54c ("PCI: rockchip: Add Rockchip PCIe controller support")
Fixes: 956cd99b35a8 ("PCI: rockchip: Separate common code from RC driver")
Fixes: 964bac9455be ("PCI: rockchip: Split out rockchip_pcie_parse_dt() to parse DT")
Signed-off-by: Chen-Yu Tsai <redacted>
---
Changes since v1:

  - Rewrite subject to match existing convention and reference
    'ep-gpios' DT property instead of the 'ep_gpio' field
---
 drivers/pci/controller/pcie-rockchip.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/controller/pcie-rockchip.c b/drivers/pci/controller/pcie-rockchip.c
index 904dec0d3a88..c95950e9004f 100644
--- a/drivers/pci/controller/pcie-rockchip.c
+++ b/drivers/pci/controller/pcie-rockchip.c

@@ -118,7 +118,7 @@ int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip)
        }

        if (rockchip->is_rc) {
-               rockchip->ep_gpio = devm_gpiod_get(dev, "ep", GPIOD_OUT_HIGH);
+               rockchip->ep_gpio = devm_gpiod_get_optional(dev, "ep", GPIOD_OUT_HIGH);
                if (IS_ERR(rockchip->ep_gpio)) {
                        dev_err(dev, "missing ep-gpios property in node\n");

You should drop the error message. What it says is now never the
reason for the error and it could most likely be a deferred probe
which you don't want an error message for.

What about switching to dev_err_probe() instead?

That way deferred probe errors get silenced (or get a better debug message),
and error messages for other issues, such as miswritten gpio properties are
still produced.

I guess, but those errors should be in the subsystem code IMO rather
than every driver.

Rob