Re: [PATCH] i2c: i2c-cadence: Don't register the adapter until it's ready

From: Mike Looijmans
Date: Fri Jan 13 2017 - 12:17:23 EST


ïOn 13-01-17 09:37, Wolfram Sang wrote:

I would argue that the "info" message means "the I2C adapter is ready for
transaction now, and we'll start initializing devices on the bus". That is
the case before it calls i2c_add_adapter().

I know what you mean, but i2c_add_adapter does more, and it can fail
because the adapter is *not* ready to transfer. Seeing the success
message before is also confusing.

When i2c_add_adapter() runs, it will start probing devices on the bus. This
yields very confusing output, as it will output things in a reversed order:

- device X on I2C bus
- device Y on I2C bus
- cdns-i2c ff030000.i2c: 100 kHz mmio ff030000 irq 197

I agree. That being said, somewhen I started working on moving such
messages into the core to save string space and have consistent output.
Then, we can print at the proper time.

So, until then, we should be consistent with the other driver, I'd say.

Makes sense.

I'll create a v2 patch to just move the i2c_add_adapter to after writing the configuration registers, and leave the dmesg output as is.

Thanks for reviewing,
Mike.


Kind regards,

Mike Looijmans
System Expert

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