commit d41f36a6464a85c06ad920703d878e4491d2c023 upstream.

The DSPI interrupt can be shared between two controllers at least on the
LX2160A. In that case, the driver for one controller might misbehave and
consume the other's interrupt. Fix this by actually checking if any of
the bits in the status register have been asserted.

Fixes: 13aed2392741 ("spi: spi-fsl-dspi: use IRQF_SHARED mode to request IRQ")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190822212450.21420-2-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 4c524191c0a21d758b519087c64f84348095e940 ]

Commit 3bd7f6589f67 ("spi: bcm2835: Overcome sglist entry length
limitation") amended the BCM2835 SPI driver with support for DMA
transfers whose buffers are not aligned to 4 bytes and require more than
one sglist entry.

When testing this feature with upcoming commits to speed up TX-only and
RX-only transfers, I noticed that SPI transmission sometimes breaks.
A function introduced by the commit, bcm2835_spi_transfer_prologue(),
performs one or two PIO transmissions as a prologue to the actual DMA
transmission.  It turns out that the breakage goes away if the DONE bit
in the CS register is set when ending such a PIO transmission.

The DONE bit signifies emptiness of the TX FIFO.  According to the spec,
the bit is of type RO, so writing it should never have any effect.
Perhaps the spec is wrong and the bit is actually of type RW1C.
E.g. the I2C controller on the BCM2835 does have an RW1C DONE bit which
needs to be cleared by the driver.  Another, possibly more likely
explanation is that it's a hardware erratum since the issue does not
occur consistently.

Either way, amend bcm2835_spi_transfer_prologue() to always write the
DONE bit.

Usually a transmission is ended by bcm2835_spi_reset_hw().  If the
transmission was successful, the TX FIFO is empty and thus the DONE bit
is set when bcm2835_spi_reset_hw() reads the CS register.  The bit is
then written back to the register, so we happen to do the right thing.

However if DONE is not set, e.g. because transmission is aborted with
a non-empty TX FIFO, the bit won't be written by bcm2835_spi_reset_hw()
and it seems possible that transmission might subsequently break.  To be
on the safe side, likewise amend bcm2835_spi_reset_hw() to always write
the bit.

Tested-by: Nuno Sá <nuno.sa@analog.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Stefan Wahren <wahrenst@gmx.net>
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Link: https://lore.kernel.org/r/edb004dff4af6106f6bfcb89e1a96391e96eb857.1564825752.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 3da9834d9381dd99273f2ad4e6d096c9187dc4f2 ]

When optional clock requesting fails, the main clock is still up and running,
we should shut it down in such caee.

Fixes: 560ee7e91009 ("spi: dw: Add support for an optional interface clock")
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Cc: Gareth Williams <gareth.williams.jx@renesas.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Gareth Williams <gareth.williams.jx@renesas.com>
Link: https://lore.kernel.org/r/20190710114243.30101-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Pull spi fixes from Mark Brown:
 "A bunch of small, device specific things here plus a DT bindings fix
  for the new validatable YAML binding format.

  The most notable thing is the fix for GPIO chip selects which fixes a
  corner case in updates of that code to modern APIs, unfortunately due
  to a historical mess the code around GPIO support is obscure, fragile
  and an ABI which makes and attempt to improve the situation painful"

* tag 'spi-fix-v5.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: pxa2xx: Add support for Intel Tiger Lake
  spi: bcm2835: Fix 3-wire mode if DMA is enabled
  spi: pxa2xx: Balance runtime PM enable/disable on error
  spi: gpio: Add SPI_MASTER_GPIO_SS flag
  spi: spi-fsl-qspi: change i.MX7D RX FIFO size
  spi: dt-bindings: spi-controller: remove unnecessary 'maxItems: 1' from reg

Intel Tiger Lake -LP LPSS SPI controller is otherwise similar than
Cannon Lake but has more controllers and up to two chip selects per
controller.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20190801134901.12635-1-jarkko.nikula@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Commit 6935224da248 ("spi: bcm2835: enable support of 3-wire mode")
added 3-wire support to the BCM2835 SPI driver by setting the REN bit
(Read Enable) in the CS register when receiving data.  The REN bit puts
the transmitter in high-impedance state.  The driver recognizes that
data is to be received by checking whether the rx_buf of a transfer is
non-NULL.

Commit 3ecd37edaa2a ("spi: bcm2835: enable dma modes for transfers
meeting certain conditions") subsequently broke 3-wire support because
it set the SPI_MASTER_MUST_RX flag which causes spi_map_msg() to replace
rx_buf with a dummy buffer if it is NULL.  As a result, rx_buf is
*always* non-NULL if DMA is enabled.

Reinstate 3-wire support by not only checking whether rx_buf is non-NULL,
but also checking that it is not the dummy buffer.

Fixes: 3ecd37edaa2a ("spi: bcm2835: enable dma modes for transfers meeting certain conditions")
Reported-by: Nuno Sá <nuno.sa@analog.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v4.2+
Cc: Martin Sperl <kernel@martin.sperl.org>
Acked-by: Stefan Wahren <wahrenst@gmx.net>
Link: https://lore.kernel.org/r/328318841455e505370ef8ecad97b646c033dc8a.1562148527.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>

Don't undo the PM initialization if we error out before we managed to
initialize it. The call to pm_runtime_disable() without being preceded
by pm_runtime_enable() would disturb the balance of the Force.

In practice, this happens if we fail to allocate any of the GPIOS ("cs",
"ready") due to -EPROBE_DEFER because we're getting probled before the
GPIO driver.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Link: https://lore.kernel.org/r/20190719122713.3444318-1-lkundrak@v3.sk
Signed-off-by: Mark Brown <broonie@kernel.org>

The GPIO SPI master has some code in its local CS
callback to set the initial sck GPIO value. This was
lost in the commit converting it to use SPI core
GPIO handling as this callback isn't called if the
internal GPIO handling is active.

Add the special SPI_MASTER_GPIO_SS to ascertain it
gets called anyway so we get the initial SCK setting
right. There is some platform provided GPIO handling
there as well but this will be skipped as the cs_gpios
will be NULL.

My test targets seem not to care about the initial
SCK value so I am uncertain if this is a regression,
but to preserve the previous semantic we better do
this.

Cc: Andrey Smirnov <andrew.smirnov@gmail.com>
Fixes: 249e2632dcd0 ("spi: gpio: Don't request CS GPIO in DT use-case")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20190716204651.7743-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

Pull driver core and debugfs updates from Greg KH:
 "Here is the "big" driver core and debugfs changes for 5.3-rc1

  It's a lot of different patches, all across the tree due to some api
  changes and lots of debugfs cleanups.

  Other than the debugfs cleanups, in this set of changes we have:

   - bus iteration function cleanups

   - scripts/get_abi.pl tool to display and parse Documentation/ABI
     entries in a simple way

   - cleanups to Documenatation/ABI/ entries to make them parse easier
     due to typos and other minor things

   - default_attrs use for some ktype users

   - driver model documentation file conversions to .rst

   - compressed firmware file loading

   - deferred probe fixes

  All of these have been in linux-next for a while, with a bunch of
  merge issues that Stephen has been patient with me for"

* tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits)
  debugfs: make error message a bit more verbose
  orangefs: fix build warning from debugfs cleanup patch
  ubifs: fix build warning after debugfs cleanup patch
  driver: core: Allow subsystems to continue deferring probe
  drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT
  arch_topology: Remove error messages on out-of-memory conditions
  lib: notifier-error-inject: no need to check return value of debugfs_create functions
  swiotlb: no need to check return value of debugfs_create functions
  ceph: no need to check return value of debugfs_create functions
  sunrpc: no need to check return value of debugfs_create functions
  ubifs: no need to check return value of debugfs_create functions
  orangefs: no need to check return value of debugfs_create functions
  nfsd: no need to check return value of debugfs_create functions
  lib: 842: no need to check return value of debugfs_create functions
  debugfs: provide pr_fmt() macro
  debugfs: log errors when something goes wrong
  drivers: s390/cio: Fix compilation warning about const qualifiers
  drivers: Add generic helper to match by of_node
  driver_find_device: Unify the match function with class_find_device()
  bus_find_device: Unify the match callback with class_find_device
  ...

The RX FIFO should be 128 byte rather than 512 byte. It's a typo on
reference manual.

Signed-off-by: Han Xu <han.xu@nxp.com>
Link: https://lore.kernel.org/r/20190710023128.13115-3-han.xu@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>