spi: indicate in the docs that per-transfer bpw setting is not supported ...

Currently it's not implemented by any driver so add a note to the
documentation.

Signed-off-by: Paul Fertser <fercerpav@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

nor: Add SPI flash driver ...

This patch adds the m25p80 driver. It has been ported from
Linux. MTD code has been removed. It has been tested with
a m25p40 chip and the Altera SPI master driver.

Signed-off-by: Franck Jullien <franck.jullien@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

spi: add bits_per_word to proxy structure ...

During the creation of a new spi device, we need to
have the possiblility to give the bits_per_word value
to master->setup.

As a matter of fact, spi master could check the spi
device bits_per_word and compare this value against its
capabilities.

Signed-off-by: Franck Jullien <franck.jullien@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

eeprom: add at25 eeprom driver ...

This commit adds support for most spi eeproms, such as the
Atmel at25 models.

Signed-off-by: Hubert Feurstein <h.feurstein@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

spi: add more spi transfer functions ...

This commit adds the following spi transfer functions:
  - spi_write
  - spi_read
  - spi_write_then_read
  - spi_w8r8

The code has been ported from the linux kernel.

Signed-off-by: Hubert Feurstein <h.feurstein@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

spi: add platform_data pointer to spi_board_info ...

In the spi layer this pointer will be assigned to the
platform_data pointer of the new spi device, thus it can
be accessed in the drivers 'probe' handler.

Signed-off-by: Hubert Feurstein <h.feurstein@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

documentation updates ...

Signed-off-by: Juergen Beisert <jbe@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

SPI: Add empty spi_register_board_info function when SPI is disabled ...

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

first (partly) running spi support

beginning of SPI support