[RTEMS Project] #1626: Can't seek in i2c eeprom devices

[RTEMS trac]

#1626: Can't seek in i2c eeprom devices
---------------------------+------------------------------
 Reporter:  angus.gratton  |       Owner:  sebastian.huber
     Type:  defect         |      Status:  assigned
 Priority:  normal         |   Milestone:  4.11
Component:  cpukit         |     Version:  4.10
 Severity:  normal         |  Resolution:
 Keywords:                 |
---------------------------+------------------------------
Changes (by joel.sherrill):

 * owner:  joel.sherrill => sebastian.huber
 * status:  new => assigned


Old description:

> lseek() doesn't seem to work when reading an I2C EEPROM on MVME3100
> (PowerPC).
>
> To reproduce:
>
> - Open EEPROM device
> - lseek() to some other offset
> - Read from EEPROM device
>
> The read will complete as if the lseek() never occured.
>
> Looking at the underlying i2c read functions in cpukit, I don't see any
> reference to offset, so I'm guessing this is unimplemented for I2C reads.
>
> However, it appears that it did once work (EPICS on RTEMS uses lseek() to
> read NVRAM values from I2C EEPROM.)
>
> Cheers - Angus

New description:

 lseek() doesn't seem to work when reading an I2C EEPROM on MVME3100
 (PowerPC).

 To reproduce:

 - Open EEPROM device
 - lseek() to some other offset
 - Read from EEPROM device

 The read will complete as if the lseek() never occured.

 Looking at the underlying i2c read functions in cpukit, I don't see any
 reference to offset, so I'm guessing this is unimplemented for I2C reads.

 However, it appears that it did once work (EPICS on RTEMS uses lseek() to
 read NVRAM values from I2C EEPROM.)

 Cheers - Angus

--

Comment:

 Nick.. please comment on the state of this. Do you have a new patch?

 Sebastian.. is this still an issue?

--
Ticket URL: <http://devel.rtems.org/ticket/1626#comment:5>
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