Re: [PATCH v6] iio: humidity: ens210: Simplify I2C functionality check

[Jonathan Cameron]

On Thu,  7 May 2026 10:21:33 +0100
Salah Triki <salah.triki@xxxxxxxxx> wrote:

> Simplify the I2C functionality check by checking for I2C_FUNC_SMBUS_EMUL,
> which encompasses the SMBus operations required by the driver.
> 
> Signed-off-by: Salah Triki <salah.triki@xxxxxxxxx>

No.  Please reread my comments on the previous. No I2C client
driver should ever use I2C_FUNC_SMBUS_EMUL.  If you are unsure
what I am referring to then ask on that thread.

Jonathan


> ---
> Changes since v5:
> - Changed patch title from "Fix missing I2C functionality checks" to
>   "Simplify I2C functionality check" to reflect the new approach.
> - Dropped the Fixes tag as the change is now considered hardening rather 
>   than a bug fix.
> - Replaced individual functionality checks with a single check for 
>   I2C_FUNC_SMBUS_EMUL as suggested by Jonathan Cameron.
> 
> Changes since v4:
> - Fixed the alignment and indentation of the I2C functionality check
>   per Andy's review.
> 
> Changes since v3:
> - Fixed the alignment and indentation of the I2C functionality check
>   per Andy's review.
> 
> Changes since v2:
> - Fixed the alignment and indentation of the I2C functionality check
>   per Maxime's review.
> 
> Changes since v1:
> - Updated the I2C functionality test to check for both required native
>   operations and SMBus emulation (`I2C_FUNC_SMBUS_EMUL`) 
> 
>  drivers/iio/humidity/ens210.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/drivers/iio/humidity/ens210.c b/drivers/iio/humidity/ens210.c
> index 77418d97f30d..91c2f69fb6bf 100644
> --- a/drivers/iio/humidity/ens210.c
> +++ b/drivers/iio/humidity/ens210.c
> @@ -201,10 +201,7 @@ static int ens210_probe(struct i2c_client *client)
>  	uint16_t part_id;
>  	int ret;
>  
> -	if (!i2c_check_functionality(client->adapter,
> -				     I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
> -				     I2C_FUNC_SMBUS_WRITE_BYTE |
> -				     I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
> +	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_EMUL)) {
>  		return dev_err_probe(&client->dev, -EOPNOTSUPP,
>  			"adapter does not support some i2c transactions\n");
>  	}