Re: [PATCH v5 2/4] ACPI: of: match PRP0001 in of_match_device

[Krzysztof Kozlowski <krzk@kernel.org>]

On Sun, Mar 29, 2026 at 08:02:16PM +0200, Markus Probst wrote:
> Export `acpi_of_match_device` function and use it to match for PRP0001
> in `of_match_device`, if the device does not have a device node.
> 
> This fixes the match data being NULL when using ACPI PRP0001, even though
> the device was matched against an of device table.

Fixes tag?

I don't see how this is going to fix !ACPI case - the
acpi_of_match_device() will just return false.


> 
> Signed-off-by: Markus Probst <markus.probst@posteo.de>
> ---
>  drivers/acpi/bus.c   |  7 ++++---
>  drivers/of/device.c  |  9 +++++++--
>  include/linux/acpi.h | 11 +++++++++++
>  3 files changed, 22 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
> index 2ec095e2009e..cd02f04cf685 100644
> --- a/drivers/acpi/bus.c
> +++ b/drivers/acpi/bus.c
> @@ -831,9 +831,9 @@ const struct acpi_device *acpi_companion_match(const struct device *dev)
>   * identifiers and a _DSD object with the "compatible" property, use that
>   * property to match against the given list of identifiers.
>   */
> -static bool acpi_of_match_device(const struct acpi_device *adev,
> -				 const struct of_device_id *of_match_table,
> -				 const struct of_device_id **of_id)
> +bool acpi_of_match_device(const struct acpi_device *adev,
> +			  const struct of_device_id *of_match_table,
> +			  const struct of_device_id **of_id)
>  {
>  	const union acpi_object *of_compatible, *obj;
>  	int i, nval;
> @@ -866,6 +866,7 @@ static bool acpi_of_match_device(const struct acpi_device *adev,
>  
>  	return false;
>  }
> +EXPORT_SYMBOL_GPL(acpi_of_match_device);
>  
>  static bool acpi_of_modalias(struct acpi_device *adev,
>  			     char *modalias, size_t len)
> diff --git a/drivers/of/device.c b/drivers/of/device.c
> index f7e75e527667..128682390058 100644
> --- a/drivers/of/device.c
> +++ b/drivers/of/device.c
> @@ -11,6 +11,7 @@
>  #include <linux/mod_devicetable.h>
>  #include <linux/slab.h>
>  #include <linux/platform_device.h>
> +#include <linux/acpi.h>
>  
>  #include <asm/errno.h>
>  #include "of_private.h"
> @@ -26,8 +27,12 @@
>  const struct of_device_id *of_match_device(const struct of_device_id *matches,
>  					   const struct device *dev)
>  {
> -	if (!matches || !dev->of_node || dev->of_node_reused)
> -		return NULL;
> +	if (!matches || !dev->of_node || dev->of_node_reused) {
> +		const struct of_device_id *id = NULL;
> +
> +		acpi_of_match_device(ACPI_COMPANION(dev), matches, &id);

I don't think this should be done from of_match_device. Yuo will have
soon recursive calls, because acpi_of_match_device() will call other
match, that will call of_match_device() and so on...

of_match_device() is supposed to match only against OF. Not ACPI. There
should be no ACPI header or code in this unit file.

Best regards,
Krzysztof