On Wed, Aug 02, 2023 at 08:30:05PM +0530, Anup Patel wrote:
> This allows fw_devlink to create device links between consumers of
> a MSI and the supplier of the MSI.
>
> Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
> ---
> drivers/of/property.c | 32 ++++++++++++++++++++++++++++++++
> 1 file changed, 32 insertions(+)
>
> diff --git a/drivers/of/property.c b/drivers/of/property.c
> index ddc75cd50825..bc20535deed7 100644
> --- a/drivers/of/property.c
> +++ b/drivers/of/property.c
> @@ -1325,6 +1325,37 @@ static struct device_node *parse_interrupts(struct device_node *np,
> return of_irq_parse_one(np, index, &sup_args) ? NULL : sup_args.np;
> }
>
> +static struct device_node *parse_msi_parent(struct device_node *np,
> + const char *prop_name, int index)
> +{
> + struct of_phandle_args sup_args;
> + struct device_node *msi_np;
> +
> + if (IS_ENABLED(CONFIG_SPARC))
> + return NULL;
> +
> + if (strcmp(prop_name, "msi-parent"))
> + return NULL;
> +
> + msi_np = of_parse_phandle(np, prop_name, 0);
> + if (msi_np) {
> + if (!of_property_read_bool(msi_np, "#msi-cells")) {
Use of_property_present() to check presence.
However, this check is wrong. #msi-cells is optional and assumed to be 0
if not present. There's another flavor of of_parse_phandle_with_args()
that allows specifying a default cell count, so I think you can get rid
of all this checking.
> + if (index) {
> + of_node_put(msi_np);
> + return NULL;
> + }
> + return msi_np;
> + }
> + of_node_put(msi_np);
> + }
> +
> + if (of_parse_phandle_with_args(np, prop_name, "#msi-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, },
> @@ -1359,6 +1390,7 @@ static const struct supplier_bindings of_supplier_bindings[] = {
> { .parse_prop = parse_regulators, },
> { .parse_prop = parse_gpio, },
> { .parse_prop = parse_gpios, },
> + { .parse_prop = parse_msi_parent, },
> {}
> };
>
> --
> 2.34.1
>
