If CONFIG_I2C is not set, build fails:

drivers/media/cec/i2c/tda9950.c: In function ‘tda9950_probe’:
drivers/media/cec/i2c/tda9950.c:391:14: error: implicit declaration of function ‘i2c_check_functionality’ [-Werror=implicit-function-declaration]
	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
      |              ^~~~~~~~~~~~~~~~~~~~~~~
  CC      crypto/aes_generic.o
drivers/media/cec/i2c/tda9950.c: At top level:
drivers/media/cec/i2c/tda9950.c:503:1: warning: data definition has no type or storage class
  503 | module_i2c_driver(tda9950_driver);
      | ^~~~~~~~~~~~~~~~~
drivers/media/cec/i2c/tda9950.c:503:1: error: type defaults to ‘int’ in declaration of ‘module_i2c_driver’ [-Werror=implicit-int]
drivers/media/cec/i2c/tda9950.c:503:1: warning: parameter names (without types) in function declaration

Add missing I2C dependency to fix this.

Fixes: caa6f4a75e9f ("media: cec: move driver for TDA9950 from drm/i2c")
Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
---
v2: Fix patch title, also cc dri-devel list
---
 drivers/media/cec/i2c/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/media/cec/i2c/Kconfig b/drivers/media/cec/i2c/Kconfig
index b9d21643eef1..c31abc26f602 100644
--- a/drivers/media/cec/i2c/Kconfig
+++ b/drivers/media/cec/i2c/Kconfig
@@ -16,6 +16,7 @@ config CEC_CH7322
 
 config CEC_NXP_TDA9950
 	tristate "NXP Semiconductors TDA9950/TDA998X HDMI CEC"
+	depends on I2C
 	select CEC_NOTIFIER
 	select CEC_CORE
 	default DRM_I2C_NXP_TDA998X
-- 
2.34.1

On 2025/3/22 10:49, Yue Haibing wrote:
> If CONFIG_I2C is not set, build fails:
> 
> drivers/media/cec/i2c/tda9950.c: In function ‘tda9950_probe’:
> drivers/media/cec/i2c/tda9950.c:391:14: error: implicit declaration of function ‘i2c_check_functionality’ [-Werror=implicit-function-declaration]
> 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
>       |              ^~~~~~~~~~~~~~~~~~~~~~~
>   CC      crypto/aes_generic.o
> drivers/media/cec/i2c/tda9950.c: At top level:
> drivers/media/cec/i2c/tda9950.c:503:1: warning: data definition has no type or storage class
>   503 | module_i2c_driver(tda9950_driver);
>       | ^~~~~~~~~~~~~~~~~
> drivers/media/cec/i2c/tda9950.c:503:1: error: type defaults to ‘int’ in declaration of ‘module_i2c_driver’ [-Werror=implicit-int]
> drivers/media/cec/i2c/tda9950.c:503:1: warning: parameter names (without types) in function declaration
> 
> Add missing I2C dependency to fix this.
> 
> Fixes: caa6f4a75e9f ("media: cec: move driver for TDA9950 from drm/i2c")

Just FYI,
commit caa6f4a75e9f has only applied to drm-misc-next, so also cc drm drivers maintainer

> Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
> ---
> v2: Fix patch title, also cc dri-devel list
> ---
>  drivers/media/cec/i2c/Kconfig | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/media/cec/i2c/Kconfig b/drivers/media/cec/i2c/Kconfig
> index b9d21643eef1..c31abc26f602 100644
> --- a/drivers/media/cec/i2c/Kconfig
> +++ b/drivers/media/cec/i2c/Kconfig
> @@ -16,6 +16,7 @@ config CEC_CH7322
>  
>  config CEC_NXP_TDA9950
>  	tristate "NXP Semiconductors TDA9950/TDA998X HDMI CEC"
> +	depends on I2C
>  	select CEC_NOTIFIER
>  	select CEC_CORE
>  	default DRM_I2C_NXP_TDA998X