Some SPI masters require slave selection before the transfer
can begin [1]. The SPI framework currently selects the chip using
either 1) the internal CS mechanism or 2) the GPIO CS, but not both.

This patch adds a new master->flags define to indicate both the GPIO
CS and the internal chip select mechanism should be used.

Tested On:
    Altera CycloneV development kit
    Compile tested for build errors on x86_64 (allyesconfigs)

[1] DesignWare dw_apb_ssi Databook, Version 3.20a (page 39)
Signed-off-by: NThor Thayer <tthayer@opensource.altera.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

To avoid warning when using i2c gpio expander change call to the
cansleep variant. There should be no issue with sleeping in the
drivers probe function.
Signed-off-by: NPhil Reid <preid@electromag.com.au>
Signed-off-by: NMark Brown <broonie@kernel.org>

Kbuild test robot reports:

  drivers/spi/spi-pxa2xx.c: In function ‘setup_cs’:
  drivers/spi/spi-pxa2xx.c:1190:20: error: implicit declaration of function ‘desc_to_gpio’
  ...

Reason for this is the fact that those functions are declared in
linux/gpio/consumer.h which is not included in the driver. Fix this by
including it.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Fix to return error code -EINVAL if no CS GPIOs available
instead of 0, as done elsewhere in this function.

Fixes: f13d4e18 ("spi: imx: Gracefully handle NULL master->cs_gpios")
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Acked-by: NMarek Vasut <marex@denx.de>
Signed-off-by: NMark Brown <broonie@kernel.org>

The driver uses custom chip_info coming from platform data for chip selects
implemented as GPIOs. If the system lacks board files setting up the
platform data, it is not possible to use GPIOs as chip selects.

This adds support for GPIO descriptors so that regardless of the underlying
firmware interface (DT, ACPI or platform data) the driver can request GPIOs
used as chip selects and configure them accordingly.

The custom chip_info GPIO support is still left there to make sure the
existing systems keep working as expected.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

It is possible that master->cs_gpios is NULL after spi_bitbang_start(),
this happens if the master has no CS GPIOs specified in DT. Check for
this case after spi_bitbang_start() to prevent NULL pointer dereference
in the subsequent for loop, which accesses the master->cs_gpios field.
Signed-off-by: NMarek Vasut <marex@denx.de>
Cc: Martin Kaiser <martin@kaiser.cx>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

This spi driver uses the common spi-bcm-qspi driver and implements iProc
SoCs specific interrupt controller. The common driver now calls the SoC
handlers when present. Adding support for both muxed l1 and unmuxed interrupt
sources.
Signed-off-by: NKamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: NYendapally Reddy Dhananjaya Reddy <yendapally.reddy@broadcom.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The return value of fsl_espi_probe (currently struct spi_master *)
is just used for checking whether an error occurred.
Change the return value type to int and simplify the code.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Simplify of_fsl_espi_probe.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Remove an unused variable.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.

Fixes: fa236a7e ("spi: bcm-qspi: Add Broadcom MSPI driver")
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

In case of error, the function kcalloc() returns NULL pointer
not ERR_PTR(). The IS_ERR() test in the return value check
should be replaced with NULL test.

Fixes: fa236a7e ("spi: bcm-qspi: Add Broadcom MSPI driver")
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The two power management functions are define inside of an #ifdef
but referenced unconditionally, which is obviously broken when
CONFIG_PM_SLEEP is not set:

drivers/spi/spi-bcm-qspi.c:1300:13: error: 'bcm_qspi_suspend' undeclared here (not in a function)
drivers/spi/spi-bcm-qspi.c:1301:13: error: 'bcm_qspi_resume' undeclared here (not in a function)

This replaces the #ifdef with a __maybe_unused annotation that lets
the compiler figure out whether to drop the functions itself,
and uses SIMPLE_DEV_PM_OPS() to refer to the functions.

This will also fill the freeze/thaw/poweroff/restore callback
pointers in addition to suspend/resume, but as far as I can tell,
this is what we want.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Fixes: fa236a7e ("spi: bcm-qspi: Add Broadcom MSPI driver")
Signed-off-by: NMark Brown <broonie@kernel.org>

The header isn't actually needed here, but including it leads
to a build warning when CONFIG_MTD is disabled:

include/linux/mtd/cfi.h:76:2: #warning No CONFIG_MTD_CFI_Ix selected. No NOR chip support can work. [-Werror=cpp]

Fixes: fa236a7e (spi: bcm-qspi: Add Broadcom MSPI driver)
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMark Brown <broonie@kernel.org>

Add definition of further register bits for use in upcoming
driver extensions and improve current bit definitions:
- use BIT macro
- use bit names as in the chip spec
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Change register access to the method used in other drivers too.
- use register names as in the chip spec for constants
- avoid hard to read statements like
  __be32 __iomem *espi_mode = &reg_base->mode
- get rid of old powerpc-specific functions like in_8

In addition annotate reg_base in struct mpc8xxx_spi as __iomem.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Simplify the interrupt handler a little. In addition don't call
fsl_espi_cpu_irq() if no event bit is set.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

If t is not null then the SPI core takes care that bits_per_word and
speed_hz are populated. This allows to simplify fsl_espi_setup_transfer.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

imx35 and compatible chipsets support loopback mode by setting a
loopback control bit in the test register. Make this setting available
for data transfers, similar to what we do for imx51.
Signed-off-by: NMartin Kaiser <martin@kaiser.cx>
Signed-off-by: NMark Brown <broonie@kernel.org>

Modify spi_imx_clkdiv_2() to return the resulting bus clock frequency
when the selected clock divider is applied. Set spi_imx->spi_bus_clk to
this frequency.

If spi_bus_clk is unset, spi_imx_calculate_timeout() causes a
division by 0.
Signed-off-by: NMartin Kaiser <martin@kaiser.cx>
Signed-off-by: NMark Brown <broonie@kernel.org>

This change implements BSPI driver for Broadcom BRCMSTB, NS2,
NSP SoCs works in combination with the MSPI controller driver
and implements flash read acceleration and implements  the
spi_flash_read() method. Both MSPI and BSPI controllers are
needed to access spi-nor flash.
Signed-off-by: NKamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: NYendapally Reddy Dhananjaya Reddy <yendapally.reddy@broadcom.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Adding the settop SoC platfrom driver, this driver is compatible
with the settop MSPI+BSPI and MSPI only blocks implemented on the
SoCs. Driver calls the spi-bcm-qspi probe(), remove() and pm_ops.
Signed-off-by: NKamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Master SPI driver for Broadcom settop, iProc SoCs. The driver
is used for devices that use SPI protocol on BRCMSTB, NSP, NS2
SoCs. SoC platform driver call exported porbe(), remove()
and suspend/resume pm_ops implemented in this common driver.
Signed-off-by: NKamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: Yendapally Reddy Dhananjaya Reddy
Signed-off-by: NMark Brown <broonie@kernel.org>

devm_* API is supposed to be used only in probe function call.
The resource is allocated at 'probe' and free automatically at 'remove'.
Usage of devm_* functions outside probe sometimes leads to resource leak.
Thus avoid using devm_* APIs in .setup/.cleanup callbacks.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Signed-off-by: NNeil Armstrong <narmstrong@baylibre.com>
Acked-by: NKevin Hilman <khilman@baylibre.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Merge both functions to reduce source code size and improve
readability.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Move checking for a zero-length message up in the call chain and
use m->frame_length instead of re-calculating the overall length
of all transfers in the message.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Factor out copying read data to the read buffers in the original
message to a new function fsl_espi_copy_from_buf.
This also allows to simplify fsl_espi_copy_to_buf.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Better structure the code by population all elements of struct
spi_transfer in one place.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Checking the message is currently done at diffrent places in the
driver. Factor it out to fsl_espi_check_message.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Most of the devices in the supported list have PXA configuration of FIFO. In
particularly Intel Medfield and Merrifield have bigger FIFO, than it's defined
for CE4100.

Split CE4100 in the similar way how it was done for Intel Quark, i.e. prefix
definitions by CE4100 and append necessary pieces of code to switch case
conditions.

We are on safe side since those bits are ignored on all LPSS IPs.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Transfer state machine in this driver does not need to set/unset pointer
to chip data between queueing and finalizing message as it is not
actually used as a state info itself but just pointer passing.

Since this per SPI device specific chip data is already carried in
ctldata use that and remove pointer to chip data from driver data.

While at it, group initialized variables before uninitialized variables
in pump_transfers().
Signed-off-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

There is no need to carry pointer to current SPI message in driver data
because cur_msg in struct spi_master holds it already when driver is using
the message queueing infrastructure from the SPI core.
Signed-off-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

All of these variables are unconditionally set before their use.
Signed-off-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Avoid ending up with a higher frequency than requested
Signed-off-by: NMatthias Seidel <kernel@mseidel.net>
Signed-off-by: NMark Brown <broonie@kernel.org>

fsl_espi_bufs and fsl_espi_cpu_bufs are very small that we can merge them.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Return a proper status code from fsl_espi_bufs instead of returning
the number of remaining words and let the caller evaluate it.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

fsl_espi_cmd_trans and fsl_espi_rw_trans share most of the code so
we can merge them.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The remaining elements of struct fsl_espi_transfer are part of struct
spi_transfer anyway. So we can get rid of struct fsl_espi_transfer
and use a struct spi_transfer only.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

If an error occurs during processing the message, then we don't have
to populate the actual_length element of struct message.
So we can get rid of element actual_length in struct
fsl_espi_transfer.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>