[PATCH 1/8] of: provide of_machine_get_compatible()

[Geert Uytterhoeven]

Hi Bartosz,

On Mon, 19 Jan 2026 at 11:40, Bartosz Golaszewski
<bartosz.golaszewski at oss.qualcomm.com> wrote:
> Provide a helper function allowing users to read the compatible string
> of the machine, hiding the access to the root node.
>
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski at oss.qualcomm.com>

Thanks for your patch!

> --- a/drivers/of/base.c
> +++ b/drivers/of/base.c
> @@ -434,6 +434,19 @@ bool of_machine_compatible_match(const char *const *compats)
>  }
>  EXPORT_SYMBOL(of_machine_compatible_match);
>
> +/**
> + * of_machine_get_compatible - Get the compatible string of this machine

... the first compatible string...

Do you see a need for adding an index parameter?

> + * @compatible: address at which the compatible string will be stored
> + *
> + * Returns:
> + * 0 on success, negative error number on failure.
> + */
> +int of_machine_get_compatible(const char **compatible)
> +{
> +       return of_property_read_string(of_root, "compatible", compatible);
> +}
> +EXPORT_SYMBOL_GPL(of_machine_get_compatible);
> +
>  /**
>   * of_machine_device_match - Test root of device tree against a of_device_id array
>   * @matches:   NULL terminated array of of_device_id match structures to search in

> --- a/include/linux/of.h
> +++ b/include/linux/of.h
> @@ -426,6 +426,8 @@ static inline bool of_machine_is_compatible(const char *compat)
>         return of_machine_compatible_match(compats);
>  }
>
> +int of_machine_get_compatible(const char **compatible);
> +
>  extern int of_add_property(struct device_node *np, struct property *prop);
>  extern int of_remove_property(struct device_node *np, struct property *prop);
>  extern int of_update_property(struct device_node *np, struct property *newprop);
>

Do you need a dummy for the !CONFIG_OF case?
This is only used by drivers/soc/fsl/guts.c, and FSL_GUTS is selected
by MMC_SDHCI_OF_ESDHC, which is OF-only, but can be enabled
when PPC || COMPILE_TEST.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds