Revert "spi: i.MX: optimize transfers for ECSPI v2.3" ...

This does not work on the Efika MX Smartbook which uses SPI
to connect the MC13892. Needs some rework.

This reverts commit 746a553.

spi: i.MX: optimize transfers for ECSPI v2.3 ...

Instead of writing one word to the txfifo and then wait until
one is received in the rxfifo we can write until the txfifos
are not full and read as long the rxfifos contain data. This
makes transfers for the m25p80 driver around 7 times faster
here.

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

spi: i.MX: create SoC specific transfer functions ...

There are SoC specific ways to optimize transfers. Make the way free
to implement these by creating SoC specific transfer functions.

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

spi: i.MX: use start mode control bit ...

The i.MX SPI controller in version 2.3 can immediately start a transfer
when the txfifo is written to. In this mode we no longer have to trigger
the transfer with the xch bit which makes the code a bit simpler.

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

Merge branch 'for-next/misc'

spi: i.MX: move register defines to include/ ...

The register defines will be used by the SPI xload code, so move
them to a place where the xload code can include them.

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

spi: only register enabled child nodes ...

Signed-off-by: Jan Luebbe <jluebbe@debian.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Abolish cpu_read* and cpu_write* accessors ...

Commit 2e6a88f2101d (add cpu native ordered io accessors) introduced
these macros and then commit be57f20cdd7d (Fix big endian MMIO
primitives) figured out they are equivalent to __raw_{read,write}*.

They turned out unnecessary after all.  Anyway, most source files
use __raw_read* and __raw_write*.

Let's replace a few remaining references and abolish them.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Merge branch 'for-next/of-device-id'

Merge branch 'for-next/mvebu'

of: use 'const void *' for struct of_device_id.data ...

Since 2011 barebox' of_device_id struct uses unsigned long type for data field:

    struct of_device_id {
            char *compatible;
            unsigned long data;
    };

Almost always struct of_device_id.data field are used as pointer
and need 'unsigned long' casting.

E.g. see 'git grep -A 4 of_device_id drivers/' output:

    drivers/ata/sata-imx.c:static __maybe_unused struct of_device_id imx_sata_dt_ids[] = {
    drivers/ata/sata-imx.c- {
    drivers/ata/sata-imx.c-         .compatible = "fsl,imx6q-ahci",
    drivers/ata/sata-imx.c-         .data = (unsigned long)&data_imx6,
    drivers/ata/sata-imx.c- }, {

Here is of_device_id struct in linux kernel v4.0:

    struct of_device_id {
            char name[32];
            char type[32];
            char compatible[128];
            const void *data;
    };

Changing of_device_id.data type to 'const void *data' will increase
barebox' linux kernel compatibility and decrease number of 'unsigned
long' casts.

Part of the patch was done using the 'coccinelle' tool with the
following semantic patch:

    @rule1@
    identifier dev;
    identifier type;
    identifier func;
    @@
    func(...) {
    <...
    - dev_get_drvdata(dev, (unsigned long *)&type)
    + dev_get_drvdata(dev, (const void **)&type)
    ...>
    }
    @rule2@
    identifier dev;
    identifier type;
    identifier func;
    identifier data;
    @@
    func(...) {
    <...
    - dev_get_drvdata(dev, (unsigned long *)&type->data)
    + dev_get_drvdata(dev, (const void **)&type->data)
    ...>
    }

Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

spi: Add SPI GPIO bitbang driver ...

This adds a driver for SPI master by GPIO pins.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

spi: ath79: move spidelay from spi-bitbang-txrx ...

Bitbang helpers for SPI require spidelay. This should be set
by the user and not the helper itself. Move it to ath79_spi
instead.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

spi: i.MX: Respect the value of 'cs_change' ...

Add the code to correctly handle 'cs_change' field in 'struct
spi_transfer'(base on the similar code from altera_spi.c)

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

driver: Call remove function only when available ...

The bus implementations currently call the drivers remove
hook unconditionally, but this hook is seldomly populated. Only call
it when it's actually populated.

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

ARM: move DMA alloc functions to dma.h ...

This better separates the DMA from the MMU functionality.

Also move all drivers that only depends on asm/mmu.h for the alloc
functions over to the common header.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

i.MX: SPI: Respect SPI_LSB_FIRST flag in mode settings ...

Add code to support SPI transfers that have data shifted out least
significant bit first. This is useful in many cases, but specifically
it is needed for drivers/firmware/altera_serial.c to work on i.MX
platform.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

drivers: remove unnecessary mach/imx-regs.h include ...

And replace the ones needed with the SoC specific header.

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

spi: mxs-spi: Allow compilation on i.MX28 only ...

The driver does not compile on i.MX23, so remove the i.MX23 from
the dependency list.

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

resource: Let dev_request_mem_region return an error pointer ...

For all users fix or add the error check.

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

treewide: remove address of the Free Software Foundation ...

The FSF address has changed; The FSF site says that
address is

  Free Software Foundation
  51 Franklin Street, Fifth Floor
  Boston, MA 02110-1301
  USA

(see http://www.fsf.org/about/contact/)

Instead of updating it each time the address changes,
just drop it completely treewide.

Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Merge branch 'for-next/omap' ...

Conflicts:
	arch/arm/configs/am335x_beaglebone_defconfig
	arch/arm/configs/am335x_defconfig

spi: i.MX: Move to coredevice_initcall ...

SPI is often used by other devices, so make sure it's initialized
early.

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

spi: omap: support swapping D0/D1 ...

The OMAP SPI core allows swapping MISO/MOSI and some boards are
wired up that way, so add a property to swap the lines.

Signed-off-by: Jan Luebbe <jlu@pengutronix.de>

Merge branch 'for-next/misc'

Merge branch 'for-next/mips' ...

Conflicts:
	arch/mips/boards/loongson-ls1b/serial.c

Merge branch 'for-next/imx'

SPI: i.MX: Remove redundant assignment ...

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

spi: altera_spi: fix altera_spi_setup() return error codes ...

Reported-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

spi: i.MX: Optimise driver private structure ...

No need to store init() function in the driver private structure
since it called only once during startup.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>