[U-Boot] [PATCH] fsl: verify writes to the MAC address EEPROM

Wolfgang Denk
2010-08-02T21:11:21Z

Dear Timur Tabi,

In message <4C57336E.7050704@freescale.com> you wrote:
> Wolfgang Denk wrote:
> > Why is this i2c_read() needed or actually useful? Should the error
> > return code from the i2c_write() above not be sufficient indication
> > that the writing failed? If that was the case, then some other parts
> > of the code need fixing.
>
> That's just the way the EEPROM chip works. When it's set into write-protect
> mode, it cheerfully accepts all of the I2C write commands, and acknowledges
> them appropriately, but it doesn't actually store the data into the EEPROM.
> The read-back is the only way I've found to verify that the write has
> actually occurred.

Is it correct to assume the the WP signal is connected to some GPIO
pin which can be set / unset in software?

Best regards,

Wolfgang Denk

--
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Lots of folks confuse bad management with destiny. -- Frank Hubbard