On Sun, Apr 4, 2021 at 8:14 PM Ilya Lipnitskiy
<ilya.lipnitskiy@xxxxxxxxx> wrote:
>
> [<vendor>,]nr-gpios property is used by some GPIO drivers[0] to indicate
> the number of GPIOs present on a system, not define a GPIO. nr-gpios is
> not configured by #gpio-cells and can't be parsed along with other
> "*-gpios" properties.
>
> scripts/dtc/checks.c also has a special case for nr-gpio{s}. However,
> nr-gpio is not really special, so we only need to fix nr-gpios suffix
> here.
The only example of this that I see is "snps,nr-gpios". I personally
would like to deprecate such overlapping/ambiguous definitions.
Maybe fix up the DT? This warning is a nice reminder that the DT needs
to be updated (if it can be). Outside of that, it's not causing any
issues that I know of.
If they are, then we can pick up a patch similar to this. I'd also
limit this fix to "snps,nr-gpios" so that future attempts to use
-gpios for anything other than listing GPIOs triggers a warning.
Rob, thoughts?
Thanks,
Saravana
>
> [0]: nr-gpios is referenced in Documentation/devicetree/bindings/gpio:
> - gpio-adnp.txt
> - gpio-xgene-sb.txt
> - gpio-xlp.txt
> - snps,dw-apb-gpio.yaml
>
> Fixes errors such as:
> OF: /palmbus@300000/gpio@600: could not find phandle
>
> Call Trace:
> of_phandle_iterator_next+0x8c/0x16c
> __of_parse_phandle_with_args+0x38/0xb8
> of_parse_phandle_with_args+0x28/0x3c
> parse_suffix_prop_cells+0x80/0xac
> parse_gpios+0x20/0x2c
> of_link_to_suppliers+0x18c/0x288
> of_link_to_suppliers+0x1fc/0x288
> device_add+0x4e0/0x734
> of_platform_device_create_pdata+0xb8/0xfc
> of_platform_bus_create+0x170/0x214
> of_platform_populate+0x88/0xf4
> __dt_register_buses+0xbc/0xf0
> plat_of_setup+0x1c/0x34
>
> Fixes: 7f00be96f125 ("of: property: Add device link support for interrupt-parent, dmas and -gpio(s)")
> Signed-off-by: Ilya Lipnitskiy <ilya.lipnitskiy@xxxxxxxxx>
> Cc: Saravana Kannan <saravanak@xxxxxxxxxx>
> Cc: <stable@xxxxxxxxxxxxxxx> # 5.5.x
> ---
> drivers/of/property.c | 11 ++++++++++-
> 1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/of/property.c b/drivers/of/property.c
> index 2bb3158c9e43..24672c295603 100644
> --- a/drivers/of/property.c
> +++ b/drivers/of/property.c
> @@ -1271,7 +1271,16 @@ DEFINE_SIMPLE_PROP(pinctrl8, "pinctrl-8", NULL)
> DEFINE_SIMPLE_PROP(remote_endpoint, "remote-endpoint", NULL)
> DEFINE_SUFFIX_PROP(regulators, "-supply", NULL)
> DEFINE_SUFFIX_PROP(gpio, "-gpio", "#gpio-cells")
> -DEFINE_SUFFIX_PROP(gpios, "-gpios", "#gpio-cells")
> +
> +static struct device_node *parse_gpios(struct device_node *np,
> + const char *prop_name, int index)
> +{
> + if (!strcmp_suffix(prop_name, "nr-gpios"))
> + return NULL;
> +
> + return parse_suffix_prop_cells(np, prop_name, index, "-gpios",
> + "#gpio-cells");
> +}
>
> static struct device_node *parse_iommu_maps(struct device_node *np,
> const char *prop_name, int index)
> --
> 2.31.1
>
