Re: regmap I3C support

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

On 11/14/24 03:31, Mark Brown wrote:
> On Wed, Nov 13, 2024 at 12:16:37PM -0800, Guenter Roeck wrote:
>> On 11/13/24 06:41, Mark Brown wrote:
> 
>>> That's kind of my question.  If we are going to have this sort of stuff
>>> we should also have it for I2C and SPI since it's such a common pattern.
> 
>> I'll take that as "we are not going to provide a dummy regmap i3c registration
>> function". Thanks, that is all I needed to know.
> 
> It's not a definite no, it's a "is this just going to run into the same
> problems we ran into with I2C and SPI and never get used?" or
> alternatively "have people figured out a better solution to the problems
> we had with I2C and SPI which we can adopt there?" - it's something we
> wanted to do before but ran into trouble with.

We now use

config SENSORS_TMP108
         tristate "Texas Instruments TMP108"
         depends on I2C
         depends on I3C || !I3C
         select REGMAP_I2C
         select REGMAP_I3C if I3C

and in the i3c_probe function

#ifdef CONFIG_REGMAP_I3C
         regmap = devm_regmap_init_i3c(i3cdev, &tmp108_regmap_config);
#else
         regmap = ERR_PTR(-ENODEV);
#endif
         if (IS_ERR(regmap))

Clumsy, and not my preferred solution, but it works.

Guenter