Re: [PATCH] mtd: spi-nor: add support for Microchip 25LC256

From: Marek Vasut
Date: Wed May 16 2018 - 10:09:54 EST


On 05/16/2018 12:05 PM, Radu Pirea wrote:
> On Wed, 2018-05-16 at 00:17 +0200, Marek Vasut wrote:
>> On 05/15/2018 06:22 PM, Radu Pirea wrote:
>>> On Fri, 2018-05-04 at 20:40 +0200, Boris Brezillon wrote:
>>>> On Fri, 4 May 2018 18:54:04 +0300
>>>> Radu Pirea <radu.pirea@xxxxxxxxxxxxx> wrote:
>>>>
>>>>> Added geometry description for Microchip 25LC256 memory.
>>>>
>>>> Same as for the dataflash stuff you posted a few weeks ago: I
>>>> don't
>>>> think this device belongs in the SPI NOR framework.
>>>
>>> Hi Boris,
>>>
>>> 25lc256 memory is similar with mr25h256, the only difference is the
>>> page size(64 vs 256). Because mr25h256 is already in SPI NOR
>>> framework
>>> I added here 25lc256.
>>
>> I think I must be reading the wrong datasheet, but can you show me
>> how
>> does it support things like READID opcode ?
>>
> Hi Marek,
>
> I read the datasheet for 25lc256 and for mr25h256 and none of them
> supports READID. Is this required for a chip to be included in spi-nor
> framework? I just followed the mr25h256 as an example.

So I thought until you pointed out the MR25 devices.

Does the 25LC device need erase or not ? I think the MR25s didn't, but I
might be wrong.

Maybe the framework could support the 25LC afterall.

--
Best regards,
Marek Vasut