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Date:   Fri, 19 Nov 2021 15:53:00 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Kumaravel.Thiagarajan@microchip.com
Cc:     lee.jones@linaro.org, Pragash.Mangalapandian@microchip.com,
        Sundararaman.H@microchip.com, axboe@kernel.dk,
        linux-block@vger.kernel.org, miquel.raynal@bootlin.com,
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        LakshmiPraveen.Kopparthi@microchip.com, Ronnie.Kunin@microchip.com
Subject: Re: Reg: New MFD Driver for my PCIe Device
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On Fri, Nov 19, 2021 at 09:16:29AM +0000, Kumaravel.Thiagarajan@microchip.com wrote:
> Dear Greg KH,
> 
> I went through the documentation of aux bus and felt that it would be the correct way to go as you said.
> I will migrate from MFD to aux bus. 
> 
> I have one more architectural question as below.
> I have written the driver such that it enumerates the OTP memory and EEPROM memory as two separate block devices or disks each of size 8KB and this enables me to use the linux dd command with "direct" option to dump the configuration binary onto OTP or EEPROM devices.
> Also, this enables me to use the application like hexedit to view the OTP or EEPROM devices in raw binary format.
> These devices are not based on mtd (memory technology device) architecture as we don't have any erase functionality here.
> Can you please let me know a suitable location in kernel source tree for my block or disk device driver?

So they are a read-only block device?

Why use a block device and not just the "normal" eeprom driver?  Or a
char device node and mmap the memory?

Anyway, no idea where to put them, drivers/misc/ ?

thanks,

greg k-h