Re: [PATCH 2/2] media: ov9282: enable single-read I2C transactions

[Alexander Stein <alexander.stein@ew.tq-group.com>]

Hi Richard,

thanks for addressing this long-standing issue.

Am Dienstag, 21. Juli 2026, 15:25:29 CEST schrieb Richard Leitner:
> Some OV9282 camera modules, such as those from Vision Components, fail
> multi-byte register reads with the default CCI I2C regmap access pattern
> and only work when single-register read transactions are used. This
> results in the driver being unable to probe due to a chip id mismatch.
> 
> As the driver has no reliable way to identify affected modules enable
> use_single_read for OV9282 unconditionally when creating the CCI regmap.

What about a property in the DT instead? In DT it should be clear if a
Vision Components camera is used.

Best regards,
Alexander

> 
> Tested on an i.M8MP system with OV9282 modules from Vision Components.
> 
> Signed-off-by: Richard Leitner <richard.leitner@linux.dev>
> ---
>  drivers/media/i2c/ov9282.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/i2c/ov9282.c b/drivers/media/i2c/ov9282.c
> index 5b6f897a74fcd..8267a0a9c6f2d 100644
> --- a/drivers/media/i2c/ov9282.c
> +++ b/drivers/media/i2c/ov9282.c
> @@ -1283,6 +1283,11 @@ static int ov9282_probe(struct i2c_client *client)
>  	struct ov9282 *ov9282;
>  	int ret;
>  
> +	const struct cci_regmap_config config = {
> +		.reg_addr_bits = 16,
> +		.use_single_read = true,
> +	};
> +
>  	ov9282 = devm_kzalloc(&client->dev, sizeof(*ov9282), GFP_KERNEL);
>  	if (!ov9282)
>  		return -ENOMEM;
> @@ -1301,7 +1306,7 @@ static int ov9282_probe(struct i2c_client *client)
>  		return ret;
>  	}
>  
> -	ov9282->regmap = devm_cci_regmap_init_i2c(client, 16);
> +	ov9282->regmap = devm_cci_regmap_init_i2c_cfg(client, &config);
>  	if (IS_ERR(ov9282->regmap))
>  		return dev_err_probe(ov9282->dev, PTR_ERR(ov9282->regmap),
>  				     "Failed to init CCI\n");
> 
> 


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