2018-01-30 17:50 GMT+01:00 Johannes Poehlmann <johannes.poehlmann@xxxxxxxxxxx>:
> The M24M01-D* eeproms are in effect 2 eeproms under 2 I2C addresses:
>
> 1. a standard 1Mbit eeprom (driver model 24c1024 is working)
>
> 2. a 256 Byte "ID page" that is a write lockable page.
> As the ID page demands 2 byte addresses, the 24c02 driver model
> can not be used.
>
> I was thinking about not to pollute the name space of chip names
> with a made up name that is not the name of a real chip.
>
> I would propose to name it "24cb02", thus making clear
> that we have a kind of 24c02 but with 2 byte address.
> (The "b" ist meant to say this)
If anything, this is just super confusing.
>
> Signed-off-by: Johannes Poehlmann <Johannes.Poehlmann@xxxxxxxxxxx>
> ---
> drivers/misc/eeprom/at24.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
> index 4d63ac8..debc8e3 100644
> --- a/drivers/misc/eeprom/at24.c
> +++ b/drivers/misc/eeprom/at24.c
> @@ -139,6 +139,7 @@ static const struct i2c_device_id at24_ids[] = {
> { "24cs01", AT24_DEVICE_MAGIC(16,
> AT24_FLAG_SERIAL | AT24_FLAG_READONLY) },
> { "24c02", AT24_DEVICE_MAGIC(2048 / 8, 0) },
> + { "24cb02", AT24_DEVICE_MAGIC(2048 / 8, AT24_FLAG_ADDR16) },
Please add the device tree support as well.
> { "24cs02", AT24_DEVICE_MAGIC(16,
> AT24_FLAG_SERIAL | AT24_FLAG_READONLY) },
> { "24mac402", AT24_DEVICE_MAGIC(48 / 8,
> --
> 2.1.4
>
Take a look at what we do with at24cs* and at24mac* models: at24cs32
stands for the serial number block, while for the regular memory area
we use at24c32.
Analogously in your case: the 'regular' memory block of this EEPROM is
compatible with 'atmel,24c1024', so this is the compatible you'll use
to access it. For the write-lockable page, it's OK to use
'atmel,24cm01'.
Best regards,
Bartosz Golaszewski
