Re: [PATCH] docs: mtd: Update spi nor reference driver

From: Vignesh Raghavendra
Date: Mon Aug 19 2019 - 00:39:59 EST


Hi,

On 16/08/19 3:50 PM, John Garry wrote:
> On 06/08/2019 17:40, Schrempf Frieder wrote:
[...]
>
> Hi,
>
> Could someone kindly advise on the following:
>
> I am looking at ACPI support only for an mtd spi nor driver we're
> targeting for mainline support.
>

If its a new driver, please add it under drivers/spi implementing SPI
MEM framework.
There are few drivers under drivers/spi that can be used as example.
(Search for "spi_mem_ops")

> So for the host, I could use a proprietary HID in the DSDT for matching
> in the kernel driver.
>
> About the child spi flash devices, is the recommendation to just use
> PRP0001 HID and "jedec,spi-nor" compatible?
>

I am not quite familiar with ACPI systems, but child flash device should
use "jedec,spi-nor" as compatible.

Regards
Vignesh

> thanks,
> John
>
>
>>
>> @Maintainers:
>> Maybe the docs under Documentation/driver-api/mtd should be officially
>> maintained by the MTD subsystem (and added to MAINTAINERS). And if there
>> will be some driver API docs for SPI MEM it should probably live in
>> Documentation/driver-api/spi instead of Documentation/driver-api/mtd, as
>> spi-mem.c itself is in drivers/spi.
>>
>> Regards,
>> Frieder
>>
>>>
>>> Thanks,
>>> John
>>>
>>>> @@ -59,7 +59,7 @@ Part III - How can drivers use the framework?
>>>>
>>>> ÂThe main API is spi_nor_scan(). Before you call the hook, a driver
>>>> should
>>>> Âinitialize the necessary fields for spi_nor{}. Please see
>>>> -drivers/mtd/spi-nor/spi-nor.c for detail. Please also refer to
>>>> fsl-quadspi.c
>>>> +drivers/mtd/spi-nor/spi-nor.c for detail. Please also refer to
>>>> spi-fsl-qspi.c
>>>> Âwhen you want to write a new driver for a SPI NOR controller.
>>>> ÂAnother API is spi_nor_restore(), this is used to restore the status
>>>> of SPI
>>>> Âflash chip such as addressing mode. Call it whenever detach the
>>>> driver from
>>>>
>>>
>>>
>>>
>>> ______________________________________________________
>>> Linux MTD discussion mailing list
>>> http://lists.infradead.org/mailman/listinfo/linux-mtd/
>
>

--
Regards
Vignesh