[U-Boot] Odd value for I2C_TIMEOUT in fsl_i2c.c

Timur Tabi
2009-09-04T18:39:26Z

Wolfgang Denk wrote:

> Probably not. If you place a read request to a slow device it may
> take tens of milliseconds, or even longer - I have no idea. IIRC we
> had a box with a LCD display connected over I2C, which didn't ent
> into production as originally designed because writing the content
> took over 100 millisec.

Well, that's an extreme case that is board-specific. Perhaps I should do this:

#ifndef CONFIG_I2C_TIMEOUT
#define CONFIG_I2C_TIMEOUT 1000
#endif

Keep in mind that so far, the number 250 has been good enough for every board to date. Why my current board is happier with 500 is a mystery to me.

Also, should we be using the same value for the timeout in i2c_wait4bus() and i2c_wait()? It looks like i2c_wait() should have a much shorter timeout than i2c_wait4bus()?

--
Timur Tabi
Linux kernel developer at Freescale