of: property: Add fw_devlink support for "gpio" and "gpios" binding

To provide backward compatibility for boards that use deprecated DT
bindings, we need to add fw_devlink support for "gpio" and "gpios".

We also need to ignore these properties on nodes with "gpio-hog"
property because their gpio[s] are all supplied by the parent node.

Fixes: e590474768f1 ("driver core: Set fw_devlink=on by default")
Cc: linux-tegra <linux-tegra@vger.kernel.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20210121225712.1118239-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/of/property.c b/drivers/of/property.c
index 5f9eed7..b2ea195 100644 (file)
--- a/drivers/of/property.c
+++ b/drivers/of/property.c
@@ -1271,6 +1271,28 @@ static struct device_node *parse_iommu_maps(struct device_node *np,
        return of_parse_phandle(np, prop_name, (index * 4) + 1);
 }
 
+static struct device_node *parse_gpio_compat(struct device_node *np,
+                                            const char *prop_name, int index)
+{
+       struct of_phandle_args sup_args;
+
+       if (strcmp(prop_name, "gpio") && strcmp(prop_name, "gpios"))
+               return NULL;
+
+       /*
+        * Ignore node with gpio-hog property since its gpios are all provided
+        * by its parent.
+        */
+       if (of_find_property(np, "gpio-hog", NULL))
+               return NULL;
+
+       if (of_parse_phandle_with_args(np, prop_name, "#gpio-cells", index,
+                                      &sup_args))
+               return NULL;
+
+       return sup_args.np;
+}
+
 static const struct supplier_bindings of_supplier_bindings[] = {
        { .parse_prop = parse_clocks, },
        { .parse_prop = parse_interconnects, },
@@ -1296,6 +1318,7 @@ static const struct supplier_bindings of_supplier_bindings[] = {
        { .parse_prop = parse_pinctrl6, },
        { .parse_prop = parse_pinctrl7, },
        { .parse_prop = parse_pinctrl8, },
+       { .parse_prop = parse_gpio_compat, },
        { .parse_prop = parse_regulators, },
        { .parse_prop = parse_gpio, },
        { .parse_prop = parse_gpios, },