[PATCH 0/5] defconfigs: add MTD_SPI_NOR (dependency for M25P80)

Marek Vasut marex at denx.de
Tue Apr 22 00:52:39 EST 2014

On Friday, April 18, 2014 at 08:30:54 AM, Brian Norris wrote:
> Hi,
> On Thu, Apr 17, 2014 at 12:53:03PM +0200, Thierry Reding wrote:
> > On Thu, Apr 17, 2014 at 12:21:44AM -0700, Brian Norris wrote:
> > > We are introducing a new SPI-NOR library/framework for MTD, to support
> > > various types of SPI-NOR flash controllers which require (or benefit
> > > from) intimate knowledge of the flash interface, rather than just the
> > > relatively dumb SPI interface. This library borrows much of the m25p80
> > > driver for its abstraction and moves this code into a spi-nor module.
> > 
> > If this is a common library, then the more common approach to solve this
> > would be to have each driver that uses it to select MTD_SPI_NOR rather
> > than depend on it. That way you can drop this whole series to update the
> > default configurations.
> But does MTD_SPI_NOR (and drivers/mtd/spi-nor/) qualify as a "library"
> or as a "subsystem"? I thought the latter were typically expected to be
> user-selectable options, not automatically-"select"ed.

I agree the "subsystem" is user-selectable while the "library" is to be 
'select'ed .

> I would say that, except for its age, MTD_SPI_NOR is very similar in to
> MTD_NAND (driver/mtd/nand/), which I'd consider a kind of subsystem, and
> which users must select before they are asked about drivers which fall
> under its category.
> Perhaps my usage of the word "library" in the description was a mistake,
> as I don't exactly consider it like a library in the sense of many other
> "select"ed libraries.

It did look like a library to me at first, but it's rather a subsystem that 
contains a small library in it. Thus, I retract my previous comment about using 
'select' and add :

Acked-by: Marek Vasut <marex at denx.de>

Best regards,
Marek Vasut

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