I2C write acknowledge polling in Linux Kernel

Question

The lackluster response here made me wonder this.

I've been saddled with a device (Analog Devices 525x) that (from the data sheet, pg 16):

disables the I2C interface during the internal [EEPROM] write cycle.

That doesn't seem fair, as in "I'm getting off the couch now, so don't use it for a while because I let one rip in the seat cushion". Honestly, why should that be my problem?

Anyway, the data sheet suggests that acknowledge polling is the answer - enter the Linux kernel... does the Linux GPIO bit bashed I2C driver provide a mechanism for doing this? Essentially send a address with the write bit set and keep doing so until an ACK appears.

I'm using 2.6.14 on an ARM with back ported GPIO bit bashing driver (from 2.6.19 I think).

Answer 1

It doesn't seem too off the shelf, but

You probably will need to look at having a protocol modification flag like Flag I2C_M_NOSTART only different, in your patches. At least there is a way to do it (admittedly a messy way)

I hope for your sake you don't need to put a normal i2c device on the same bus.

Honestly, hardware vendors do stuff like this all the time. They consider the problem "solved" as long as it becomes yours.

I see lots of broken I2C out there and you could make life nicer for other people.