Re: [spi-devel-general] [PATCH v2 3/6] mtd: m25p80: add support to parse the SPI flash's partitions

[Anton Vorontsov <cbouatmailru@gmail.com>]

On Tue, Aug 10, 2010 at 08:56:42AM -0600, Grant Likely wrote:
[...] 
> The suggestion has been raised to use something like bus notifiers to
> get a hook onto the device registration before the driver is probed so
> that the platform_data can be translated in an separate chuck of code,
> but down that path lies insanity.  There are all kinds of ordering
> issues (like making sure the translation code is called before the
> driver probe code), and it is a lot of complexity for what is really a
> simple thing.

There's another option: platform data handlers (they could be
chained, in case if we want to use several methods of obtaining
platform data, i.e. "try raw data, then ACPI, then OF").

See include/linux/spi/mmc_spi.h (mmc_spi_get_pdata)
and drivers/mmc/host/of_mmc_spi.c.

I think we might implement some library to make these handlers
more generic, but even the simple implementation as in mmc_spi
case proves that it is possible to separate OF/ACPI/DMI/whatever
handling from the generic code.

-- 
Anton Vorontsov
email: cbouatmailru@gmail.com
irc://irc.freenode.net/bd2