Re: [RFC PATCH 0/6] nvmem: add block device NVMEM provider

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Fri, Jul 21, 2023 at 04:32:49PM +0800, Ming Lei wrote:
> On Wed, Jul 19, 2023 at 11:01:14PM +0100, Daniel Golle wrote:
> > On embedded devices using an eMMC it is common that one or more (hw/sw)
> > partitions on the eMMC are used to store MAC addresses and Wi-Fi
> > calibration EEPROM data.
> > 
> > Implement an NVMEM provider backed by block devices as typically the
> > NVMEM framework is used to have kernel drivers read and use binary data
> > from EEPROMs, efuses, flash memory (MTD), ...
> > 
> > In order to be able to reference hardware partitions on an eMMC, add code
> > to bind each hardware partition to a specific firmware subnode.
> > 
> > This series is meant to open the discussion on how exactly the device tree
> > schema for block devices and partitions may look like, and even if using
> > the block layer to back the NVMEM device is at all the way to go -- to me
> > it seemed to be a good solution because it will be reuable e.g. for NVMe.
> 
> Just wondering why you don't use request_firmware() in drivers which consume
> the data, then the logic can be moved out of kernel, and you needn't to deal
> with device tree & block device.
> 
> Or Android doesn't support udev and initrd?

It does support initrd, but not really udev last I looked.

But it does allow request_firmware() to be called at boot time, so yes,
finding out why that isn't used here would be good.

thanks,

greg k-h