Hello jfaslist,
on Wed, 03 May 2006 14:33:37 jfaslist wrote:
> But when we try to access i2c devices from under linux 2.6 using
> the /dev/i2c-0 special file we get an ENODEV on opening that
> file. I think it is because we lack an adapter driver.
>
> If I look in the official kernel, it looks like the adapter
> driver for the mpc8270 i2c system is
> ./drivers/i2c/busses/i2c-mpc.c. Is this correct?
No. It is for:
MODULE_DESCRIPTION
("I2C-Bus adapter for MPC107 bridge and MPC824x/85xx/52xx processors");
> In DENX ELDK there is also a i2c-mpc8260.c, but we couldn't get
> that to work either.
OK, this was the right driver ... but it was tested on a MPC826x
Processor.
Hmmm.... I think there are differences in the memory map between
MPC826x and MPC827x ... can you try following Hack in
include/asm-ppc/cpm_8260.h?
-#define PROFF_I2C ((16 * 1024) - 64)
+#define PROFF_I2C ((8 * 1024) - 64)
[If it solves the problem, we must do this on a better way ;-)]
I think i had the same problem with a 2.4er Kernel ... Yes,
this is in my queue, but not merged in our official 2.4er Tree ...
Maybe you have to set other Portsettings in
drivers/i2c/busses/i2c-cpm2.c cpm2_iic_init() ... ?
> What should I do to be able to access i2c devices using the
> /dev/i2c-0 file? I feel I need to modify the i2c adapter driver
> to follow the driver model, but in what ways?
Bring up the driver running, and then read:
Documentation/i2c/dev-interface.
Best regards
Heiko
