Re: [PATCH v3 12/12] mtd: mtdpart: Don't create platform device that'll never probe

[Maxim Kiselev]

вт, 7 февр. 2023 г. в 04:42, Saravana Kannan <saravanak@xxxxxxxxxx>:
>
> These "nvmem-cells" platform devices never get probed because there's no
> platform driver for it and it's never used anywhere else. So it's a
> waste of memory. These devices also cause fw_devlink to block nvmem
> consumers of "nvmem-cells" partition from probing because the supplier
> device never probes.
>
> So stop creating platform devices for nvmem-cells partitions to avoid
> wasting memory and to avoid blocking probing of consumers.
>
> Reported-by: Maxim Kiselev <bigunclemax@xxxxxxxxx>
> Fixes: bcdf0315a61a ("mtd: call of_platform_populate() for MTD partitions")
> Signed-off-by: Saravana Kannan <saravanak@xxxxxxxxxx>
> ---
>  drivers/mtd/mtdpart.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
>
> diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
> index d442fa94c872..85f5ee6f06fc 100644
> --- a/drivers/mtd/mtdpart.c
> +++ b/drivers/mtd/mtdpart.c
> @@ -577,6 +577,7 @@ static int mtd_part_of_parse(struct mtd_info *master,
>  {
>         struct mtd_part_parser *parser;
>         struct device_node *np;
> +       struct device_node *child;
>         struct property *prop;
>         struct device *dev;
>         const char *compat;
> @@ -594,6 +595,15 @@ static int mtd_part_of_parse(struct mtd_info *master,
>         else
>                 np = of_get_child_by_name(np, "partitions");
>
> +       /*
> +        * Don't create devices that are added to a bus but will never get
> +        * probed. That'll cause fw_devlink to block probing of consumers of
> +        * this partition until the partition device is probed.
> +        */
> +       for_each_child_of_node(np, child)
> +               if (of_device_is_compatible(child, "nvmem-cells"))
> +                       of_node_set_flag(child, OF_POPULATED);
> +
>         of_property_for_each_string(np, "compatible", prop, compat) {
>                 parser = mtd_part_get_compatible_parser(compat);
>                 if (!parser)
> --
> 2.39.1.519.gcb327c4b5f-goog
>

Hi, Saravana!

Now it works pretty well. Thank you so much for your efforts.

> Reported-by: Maxim Kiselev <bigunclemax@xxxxxxxxx>
> Fixes: bcdf0315a61a ("mtd: call of_platform_populate() for MTD partitions")
> Signed-off-by: Saravana Kannan <saravanak@xxxxxxxxxx>

Tested-by: Maksim Kiselev <bigunclemax@xxxxxxxxx>