Hi all,

After merging the driver-core tree, today's linux-next build (x86_64
allmodconfig) failed like this:

drivers/leds/leds-turris-omnia.c: In function 'omnia_find_mcu_and_get_features':
drivers/leds/leds-turris-omnia.c:457:56: error: passing argument 3 of 'device_find_child' from incompatible pointer type [-Wincompatible-pointer-types]
  457 |         mcu_dev = device_find_child(dev->parent, NULL, omnia_match_mcu_client);
      |                                                        ^~~~~~~~~~~~~~~~~~~~~~
      |                                                        |
      |                                                        int (*)(struct device *, void *)
In file included from include/linux/acpi.h:14,
                 from include/linux/i2c.h:13,
                 from drivers/leds/leds-turris-omnia.c:8:
include/linux/device.h:1085:49: note: expected 'device_match_t' {aka 'int (*)(struct device *, const void *)'} but argument is of type 'int (*)(struct device *, void *)'
 1085 |                                  device_match_t match);
      |                                  ~~~~~~~~~~~~~~~^~~~~

Caused by commit

  f1e8bf56320a ("driver core: Constify API device_find_child() and adapt for various usages")

interacting with commit

  b4c3960da27d ("leds: turris-omnia: Use command execution functions from the MCU driver")

from the leds-lj tree.

I have applied the following merge fix patch.

From: Stephen Rothwell <sfr@canb.auug.org.au>
Date: Mon, 6 Jan 2025 15:58:47 +1100
Subject: [PATCH] fix up 2 for "driver core: Constify API device_find_child()
 and adapt for various usages"

interacting with commit

  b4c3960da27d ("leds: turris-omnia: Use command execution functions from the MCU driver")

from the leds-lj tree.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
---
 drivers/leds/leds-turris-omnia.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/leds/leds-turris-omnia.c b/drivers/leds/leds-turris-omnia.c
index 7d3b24c8ecae..4fe1a9c0bc1b 100644
--- a/drivers/leds/leds-turris-omnia.c
+++ b/drivers/leds/leds-turris-omnia.c
@@ -438,7 +438,7 @@ static int omnia_mcu_get_features(const struct i2c_client *mcu_client)
 	return reply;
 }
 
-static int omnia_match_mcu_client(struct device *dev, void *data)
+static int omnia_match_mcu_client(struct device *dev, const void *data)
 {
 	struct i2c_client *client;
 
-- 
2.45.2

-- 
Cheers,
Stephen Rothwell

On 1/6/2025 1:04 PM, Stephen Rothwell wrote:
> Hi all,
> 
> After merging the driver-core tree, today's linux-next build (x86_64
> allmodconfig) failed like this:
> 
> drivers/leds/leds-turris-omnia.c: In function 'omnia_find_mcu_and_get_features':
> drivers/leds/leds-turris-omnia.c:457:56: error: passing argument 3 of 'device_find_child' from incompatible pointer type [-Wincompatible-pointer-types]
>   457 |         mcu_dev = device_find_child(dev->parent, NULL, omnia_match_mcu_client);
>       |                                                        ^~~~~~~~~~~~~~~~~~~~~~
>       |                                                        |
>       |                                                        int (*)(struct device *, void *)
> In file included from include/linux/acpi.h:14,
>                  from include/linux/i2c.h:13,
>                  from drivers/leds/leds-turris-omnia.c:8:
> include/linux/device.h:1085:49: note: expected 'device_match_t' {aka 'int (*)(struct device *, const void *)'} but argument is of type 'int (*)(struct device *, void *)'
>  1085 |                                  device_match_t match);
>       |                                  ~~~~~~~~~~~~~~~^~~~~
> 
> Caused by commit
> 
>   f1e8bf56320a ("driver core: Constify API device_find_child() and adapt for various usages")
> 
> interacting with commit
> 
>   b4c3960da27d ("leds: turris-omnia: Use command execution functions from the MCU driver")
> 
> from the leds-lj tree.
> 
> I have applied the following merge fix patch.
> 
> From: Stephen Rothwell <sfr@canb.auug.org.au>
> Date: Mon, 6 Jan 2025 15:58:47 +1100
> Subject: [PATCH] fix up 2 for "driver core: Constify API device_find_child()
>  and adapt for various usages"
> 
> interacting with commit
> 
>   b4c3960da27d ("leds: turris-omnia: Use command execution functions from the MCU driver")
> 
> from the leds-lj tree.
> 
> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
> ---
>  drivers/leds/leds-turris-omnia.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/leds/leds-turris-omnia.c b/drivers/leds/leds-turris-omnia.c
> index 7d3b24c8ecae..4fe1a9c0bc1b 100644
> --- a/drivers/leds/leds-turris-omnia.c
> +++ b/drivers/leds/leds-turris-omnia.c
> @@ -438,7 +438,7 @@ static int omnia_mcu_get_features(const struct i2c_client *mcu_client)
>  	return reply;
>  }
>  
> -static int omnia_match_mcu_client(struct device *dev, void *data)
> +static int omnia_match_mcu_client(struct device *dev, const void *data)
>  {
>  	struct i2c_client *client;
>  
LGTM, thank you Stephen for this fix.
Reviewed-by: Zijun Hu <quic_zijuhu@quicinc.com>