Re: [PATCH v3 4/5] hwmon: tmp108: Add support for I3C device

[Guenter Roeck <linux@roeck-us.net>]

On 11/11/24 10:10, Guenter Roeck wrote:
> On 11/11/24 10:04, Guenter Roeck wrote:
> [ ... ]
>>> +static int p3t1085_i3c_probe(struct i3c_device *i3cdev)
>>> +{
>>> +    struct device *dev = i3cdev_to_dev(i3cdev);
>>> +    struct regmap *regmap;
>>> +
>>> +    regmap = devm_regmap_init_i3c(i3cdev, &tmp108_regmap_config);
>>> +    if (IS_ERR(regmap))
>>> +        return dev_err_probe(dev, PTR_ERR(regmap),
>>> +                     "Failed to register i3c regmap\n");
>>> +
>>> +    return tmp108_common_probe(dev, regmap, "p3t1085_i3c");
>>> +}
>>> +
>>> +static struct i3c_driver p3t1085_driver = {
>>> +    .driver = {
>>> +        .name = "p3t1085_i3c",
>>> +    },
>>> +    .probe = p3t1085_i3c_probe,
>>> +    .id_table = p3t1085_i3c_ids,
>>> +};
>>> +module_i3c_driver(p3t1085_driver);
>>> +#endif
>>
>> While looking at i3c code, I found module_i3c_i2c_driver(). Can we use
>> that function to register both i2c and i3c in one call ?
>>
> Answering my own question: No, because devm_regmap_init_i3c()
> does not provide a dummy function if i3C is not enabled.
> 

I do have another concern, though: What happens if the i2c part of the driver
registers and the i3c part fails to register ? module_i3c_i2c_driver() handles
that situation by unregistering the i2c driver, but I don't really know
what happens if a single module registers two drivers and one of them fails.

Thanks,
Guenter