[PATCH 1/4] dt-bindings: at25: add Fujitsu MB85RS4MT

[Tudor.Ambarus at microchip.com]

On 3/10/21 12:59 AM, Michael Walle wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> Hi Tim,
> 
> Am 2021-03-09 23:00, schrieb Tim Harvey:
>> Document the compatible value for the Fujitsu MB85RS4MT SPI
>> FRAM EEPROM device so that it can be used in DTS files.
>>
>> This is a 512KiB FRAM EEPROM.
>>
>> Signed-off-by: Tim Harvey <tharvey at gateworks.com>
>> ---
>>  Documentation/devicetree/bindings/eeprom/at25.yaml | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/Documentation/devicetree/bindings/eeprom/at25.yaml
>> b/Documentation/devicetree/bindings/eeprom/at25.yaml
>> index 6a2dc8b3ed14..f594db72b711 100644
>> --- a/Documentation/devicetree/bindings/eeprom/at25.yaml
>> +++ b/Documentation/devicetree/bindings/eeprom/at25.yaml
>> @@ -26,6 +26,7 @@ properties:
>>                - anvo,anv32e61w
>>                - atmel,at25256B
>>                - fujitsu,mb85rs1mt
>> +              - fujitsu,mb85rs4mt
>>                - fujitsu,mb85rs64
>>                - microchip,at25160bn
>>                - microchip,25lc040
> 
> Hm, the driver is spi-nor but this is for the at25 driver. Is
> this correct? Doesn't it work if you just add the ID to
> spi-nor/fujitsu.c and use 'compatible = "jedec,spi-nor' ?
> 

Tim,

Can you try and see if you can work with this flash by setting "atmel,at25"
compatible?

There are some SPI NOR-like flashes MRAMs, FRAMs, even EEPROMs, that share
a part of opcodes of SPI NORs, but have slightly different characteristics
(ex. no erase, no wait times for writes on FRAMs).
See the patch series submitted by Richard, that I have stalled:
https://patchwork.ozlabs.org/project/linux-mtd/list/?series=208584&state=*

I now have time to allocate for this, I'll study all and come up with a proposal
in one or two weeks.

Cheers,
ta