Merge series "spi: spi-geni-qcom: Avoid a bunch of per-transfer overhead" from Douglas Anderson <dianders@chromium.org>:

This series tries to reduce a whole bunch of overhead in each SPI
transfer.  Much of this overhead is new with the recent interconnect
changes, but even without those changes we still had some overhead
that we could avoid.  Let's avoid all of it.

These changes are atop the Qualcomm tree to avoid merge conflicts.  If
they look good, the most expedient way to land them is probably to get
Ack's from Mark and land then via the Qualcomm tree.

Most testing was done on the Chrome OS 5.4 tree, but sanity check was
done on mainline.

Douglas Anderson (3):
  spi: spi-geni-qcom: Avoid clock setting if not needed
  spi: spi-geni-qcom: Set an autosuspend delay of 250 ms
  spi: spi-geni-qcom: Get rid of most overhead in prepare_message()

 drivers/spi/spi-geni-qcom.c | 67 ++++++++++++++++++-------------------
 1 file changed, 32 insertions(+), 35 deletions(-)

--
2.27.0.383.g050319c2ae-goog

Merge series "spi: spi-sun6i: One fix and some improvements" from Marc Kleine-Budde <mkl@pengutronix.de>:

Hello,

this series first fixes the calculation of the clock rate. The driver will
round up to the nearest clock rate instead of rounding down. Resulting in SPI
devices accessed with a too high SPI clock.

The remaining patches improve the performance of the driver. The changes range
from micro-optimizations like reducing MMIO writes to the controller to
reducing the number of needed interrupts in some use cases.

regards,
Marc

changes since v1:
- added Maxime Ripard's to the existing patches
- 06/10: (was 05/10 in v1)
  "spi: spi-sun6i: sun6i_spi_drain_fifo(): introduce sun6i_spi_get_rx_fifo_count() and make use of it"
  use FIELD_GET instead of open coding it
  (tnx: Maxime Ripard)
- 05/10: "spi: spi-sun6i: sun6i_spi_get_tx_fifo_count: Convert manual shift+mask to FIELD_GET()"
  new patch

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

There is no need to call spi_master_put() if spi_alloc_master()
failed, it should return -ENOMEM directly.
Signed-off-by: Peng Fan <fanpeng@loongson.cn>
Link: https://lore.kernel.org/r/1594111842-9468-1-git-send-email-fanpeng@loongson.cnSigned-off-by: Mark Brown <broonie@kernel.org>

In commit 0e3b8a81 ("spi: spi-geni-qcom: Add interconnect
support") the spi_geni_runtime_suspend() and spi_geni_runtime_resume()
became a bit slower.  Measuring on my hardware I see numbers in the
hundreds of microseconds now.

Let's use autosuspend to help avoid some of the overhead.  Now if
we're doing a bunch of transfers we won't need to be constantly
chruning.

The number 250 ms for the autosuspend delay was picked a bit
arbitrarily, so if someone has measurements showing a better value we
could easily change this.

Fixes: 0e3b8a81 ("spi: spi-geni-qcom: Add interconnect support")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Akash Asthana<akashast@codeaurora.org>
Link: https://lore.kernel.org/r/20200701174506.2.I9b8f6bb1e7e6d8847e2ed2cf854ec55678db427f@changeidSigned-off-by: Mark Brown <broonie@kernel.org>

In sun6i_spi_transfer_one() the RX FIFO Ready (SUN6I_INT_CTL_RF_RDY) is
unconditionally enabled.

A RX interrupt is only needed, if more data than fits into the FIFO is going to
be received during this transfer. As the RX-FIFO is drained during transfer
complete interrupt, enable the RX FIFO Ready interrupt only if the data doesn't
fit into the FIFO.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-11-mkl@pengutronix.deSigned-off-by: Mark Brown <broonie@kernel.org>

In sun6i_spi_transfer_one() the Interrupt Control Register is written three
times. This patch collates the three writes into one.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-10-mkl@pengutronix.deSigned-off-by: Mark Brown <broonie@kernel.org>

The function sun6i_spi_fill_fifo() is called with a length argument of
"sspi->fifo_depth" and "SUN6I_FIFO_DEPTH".

The driver reads the number of free bytes in the FIFO from the hardware and
uses the length argument to limit this value. This is not needed as the number
of free bytes in the FIFO is always less or equal the depth of the FIFO.

This patch removes the length argument and check.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-9-mkl@pengutronix.deSigned-off-by: Mark Brown <broonie@kernel.org>

The function sun6i_spi_drain_fifo() is called with a length argument of
"sspi->fifo_depth" and "SUN6I_FIFO_DEPTH".

The driver reads the number of available bytes to read from the FIFO from the
hardware and uses the length argument to limit this value. This is not needed
as the FIFO can contain only the fifo depth number of bytes.

This patch removes the length argument and check.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-8-mkl@pengutronix.deSigned-off-by: Mark Brown <broonie@kernel.org>

This patch introduces the function sun6i_spi_get_rx_fifo_count(), similar to
the existing sun6i_spi_get_tx_fifo_count(), to make the sun6i_spi_drain_fifo()
function a bit easier to read.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-7-mkl@pengutronix.deSigned-off-by: Mark Brown <broonie@kernel.org>

This patch converts the manual shift+mask in sun6i_spi_get_tx_fifo_count() to
make use of FIELD_GET()
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20200706143443.9855-6-mkl@pengutronix.deSigned-off-by: Mark Brown <broonie@kernel.org>

In sun6i_spi_transfer_one() the driver ensures that the length of the transfer
is smaller or equal to SUN6I_MAX_XFER_SIZE. This means the masking of the
length to SUN6I_MAX_XFER_SIZE can be skipped when writing the transfer length
into the registers.

This patch removes the useless masking of the transfer length to
SUN6I_MAX_XFER_SIZE.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-5-mkl@pengutronix.deSigned-off-by: Mark Brown <broonie@kernel.org>

This patch removes an useless goto at the end of
sun6i_spi_transfer_one().
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-4-mkl@pengutronix.deSigned-off-by: Mark Brown <broonie@kernel.org>

This patch implementes the reporting of the effectivly used speed_hz for the
transfer by setting tfr->effective_speed_hz.

See the following patch, which adds this feature to the SPI core for more
information:

    5d7e2b5e spi: core: allow reporting the effectivly used speed_hz for a transfer
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-3-mkl@pengutronix.deSigned-off-by: Mark Brown <broonie@kernel.org>

A SPI transfer defines the _maximum_ speed of the SPI transfer. However the
driver doesn't take into account that the clock divider is always rounded down
(due to integer arithmetics). This results in a too high clock rate for the SPI
transfer.

E.g.: with a mclk_rate of 24 MHz and a SPI transfer speed of 10 MHz, the
original code calculates a reg of "0", which results in a effective divider of
"2" and a 12 MHz clock for the SPI transfer.

This patch fixes the issue by using DIV_ROUND_UP() instead of a plain
integer division.

While there simplify the divider calculation for the CDR1 case, use
order_base_2() instead of two ilog2() calculations.

Fixes: 3558fe90 ("spi: sunxi: Add Allwinner A31 SPI controller driver")
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-2-mkl@pengutronix.deSigned-off-by: Mark Brown <broonie@kernel.org>

Merge series "Add Renesas RPC-IF support" from Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>:

Hello!

Here's a set of 2 patches against Linus' repo. Renesas Reduced Pin Count
Interface (RPC-IF) allows a SPI flash or HyperFlash connected to the SoC
to be accessed via the external address space read mode or the manual mode.
The memory controller driver for RPC-IF registers either SPI or HyperFLash
subdevice, depending on the contents of the device tree subnode; it also
provides the abstract "back end" API that can be used by the "front end"
SPI/MTD drivers to talk to the real hardware...

Based on the original patch by Mason Yang <masonccyang@mxic.com.tw>.

[1/2] dt-bindings: memory: document Renesas RPC-IF bindings
[2/2] memory: add Renesas RPC-IF driver

MBR, Sergei

Merge series "spi: bcm2835: Interrupt-handling optimisations" from Robin Murphy <robin.murphy@arm.com>:

Hi all,

Although Florian was concerned about a trivial inline check to deal with
shared IRQs adding overhead, the reality is that it would be so small as
to not be worth even thinking about unless the driver was already tuned
to squeeze out every last cycle. And a brief look over the code shows
that that clearly isn't the case.

This is an example of some of the easy low-hanging fruit that jumps out
just from code inspection. Based on disassembly and ARM1176 cycle
timings, patch #2 should save the equivalent of 2-3 shared interrupt
checks off the critical path in all cases, and patch #3 possibly up to
about 100x more. I don't have any means to test these patches, let alone
measure performance, so they're only backed by the principle that less
code - and in particular fewer memory accesses - is almost always
better.

There is almost certainly a *lot* more to be had from careful use of
relaxed I/O accessors, not doing a read-modify-write of CS at every
reset, tweaking the loops further to avoid unnecessary writebacks to
variables, and so on. However since I'm not invested in this personally
I'm not going to pursue it any further; I'm throwing these patches out
as more of a demonstration to back up my original drive-by review
comments, so if anyone want to pick them up and run with them then
please do so.

Robin.

Robin Murphy (3):
  spi: bcm3835: Tidy up bcm2835_spi_reset_hw()
  spi: bcm2835: Micro-optimise IRQ handler
  spi: bcm2835: Micro-optimise FIFO loops

 drivers/spi/spi-bcm2835.c | 45 +++++++++++++++++++--------------------
 1 file changed, 22 insertions(+), 23 deletions(-)

--
2.23.0.dirty

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

This switches the Lantiq SSC driver over to use GPIO descriptor
handling in the core.

The driver was already utilizing the core to look up and request
GPIOs from the device tree so this is a pretty small change
just switching it over to use descriptors directly instead.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Link: https://lore.kernel.org/r/20200625202149.209276-1-linus.walleij@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

This converts the IMG SPFI SPI driver to use GPIO descriptors
as obtained from the core instead of GPIO numbers.

The driver was already relying on the core code to look up
the GPIO numbers from the device tree and allocate memory for
storing state etc. By moving to use descriptors handled by
the core we can delete the setup/cleanup functions and
the device state handler that were only dealing with this.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Ionela Voinescu <ionela.voinescu@imgtec.com>
Cc: Sifan Naeem <sifan.naeem@imgtec.com>
Link: https://lore.kernel.org/r/20200625201422.208640-1-linus.walleij@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

The Nuvoton PSPI driver already uses the core to handle GPIO
chip selects but is using the old GPIO number method and
retrieveing the GPIOs in the probe() call.

Switch it over to using GPIO descriptors saving a bunch of
code and modernizing it.

Compile tested med ARMv7 multiplatform config augmented
with the Nuvoton arch and this driver.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Tomer Maimon <tmaimon77@gmail.com>
Link: https://lore.kernel.org/r/20200625225759.273911-1-linus.walleij@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

On some SPI controllers (like spi-geni-qcom) setting the chip select
is a heavy operation.  For instance on spi-geni-qcom, with the current
code, is was measured as taking upwards of 20 us.  Even on SPI
controllers that aren't as heavy, setting the chip select is at least
something like a MMIO operation over some peripheral bus which isn't
as fast as a RAM access.

While it would be good to find ways to mitigate problems like this in
the drivers for those SPI controllers, it can also be noted that the
SPI framework could also help out.  Specifically, in some situations,
we can see the SPI framework calling the driver's set_cs() with the
same parameter several times in a row.  This is specifically observed
when looking at the way the Chrome OS EC SPI driver (cros_ec_spi)
works but other drivers likely trip it to some extent.

Let's solve this by caching the chip select state in the core and only
calling into the controller if there was a change.  We check not only
the "enable" state but also the chip select mode (active high or
active low) since controllers may care about both the mode and the
enable flag in their callback.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200629164103.1.Ied8e8ad8bbb2df7f947e3bc5ea1c315e041785a2@changeidSigned-off-by: Mark Brown <broonie@kernel.org>

The field mspi->reg_base is annotated as an __iomem pointer. Good.

However, this field is often assigned to a temporary variable:
before being used. For example:
	struct fsl_spi_reg *reg_base = mspi->reg_base;

But this variable is missing the __iomem annotation.
So, add the missing __iomem and make sparse & the bot happier.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Link: https://lore.kernel.org/r/20200622162611.83694-1-luc.vanoostenryck@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

Add the memory driver for Renesas RPC-IF which registers either SPI or
HyperFLash device depending on the contents of the device tree subnode.
It also provides the absract "back end" device APIs that can be used by
the "front end" SPI/MTD drivers to talk to the real hardware.

Based on the original patch by Mason Yang <masonccyang@mxic.com.tw>.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Link: https://lore.kernel.org/r/9a3606ec-d4d0-c63a-4fb6-631ab38e621c@cogentembedded.comSigned-off-by: Mark Brown <broonie@kernel.org>

Renesas Reduced Pin Count Interface (RPC-IF) allows a SPI flash or
HyperFlash connected to the SoC to be accessed via the external address
space read mode or the manual mode.

Document the device tree bindings for the Renesas RPC-IF found in the R-Car
gen3 SoCs.

Based on the original patch by Mason Yang <masonccyang@mxic.com.tw>.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Link: https://lore.kernel.org/r/54a84c75-fa17-9976-d9a6-a69ef67c418b@cogentembedded.comSigned-off-by: Mark Brown <broonie@kernel.org>

The blind and counted loops are always called with nonzero count, so
convert them to do-while loops that lead to slightly more efficient
code generation. With GCC 8.3 this shaves off 1-2 instructions per
iteration in each case.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/9242863077acf9a64e4b3720e479855b88d19e82.1592261248.git.robin.murphy@arm.comSigned-off-by: Mark Brown <broonie@kernel.org>

The IRQ handler only needs the struct spi_controller for the sake of
the completion at the end of a transfer. Passing the struct bcm2835_spi
directly as the IRQ data allows that level of indirection to be pushed
into the completion path for the reverse lookup, and avoided entirely
in all other cases.

This saves one explicit load in the critical path, plus (for a GCC 8.3
build) two registers worth of stack frame overhead.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/6b401cb521539caffab21f05b4c8cba6c9d27c6e.1592261248.git.robin.murphy@arm.comSigned-off-by: Mark Brown <broonie@kernel.org>

It doesn't need a struct spi_controller, and every callsite has
already retrieved the appropriate struct bcm2835_spi, so just pass
that directly.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/eca458ae1a0d3934d0627f90e25d294fefd4b13d.1592261248.git.robin.murphy@arm.comSigned-off-by: Mark Brown <broonie@kernel.org>

this patch use correct SPI_CFG2_REG offset.
Signed-off-by: leilk.liu <leilk.liu@mediatek.com>
Link: https://lore.kernel.org/r/20200701090020.7935-1-leilk.liu@mediatek.comSigned-off-by: Mark Brown <broonie@kernel.org>

The OMAP2 MCSPI has some kind of half-baked GPIO CS support:
it includes code like this:

  if (gpio_is_valid(spi->cs_gpio)) {
        ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev));
	(...)

But it doesn't parse the "cs-gpios" attribute in the device
tree to count the number of GPIOs or pick out the GPIO numbers
and put these in the SPI master's .cs_gpios property.

We complete the implementation of supporting CS GPIOs
from the device tree and switch it over to use the SPI core
for this.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20200625231257.280615-1-linus.walleij@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

Setting the chip select on the Qualcomm geni SPI controller isn't
exactly cheap.  Let's cache the current setting and avoid setting the
chip select if it's already right.

Using "flashrom" to read or write the EC firmware on a Chromebook
shows roughly a 25% reduction in interrupts and a 15% speedup.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200626151946.1.I06134fd669bf91fd387dc6ecfe21d44c202bd412@changeidSigned-off-by: Mark Brown <broonie@kernel.org>

Add Intel Tiger Lake PCH-H PCI IDs.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20200625140041.745804-1-jarkko.nikula@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

Add the MODULE_DEVICE_TABLE macro for the platform_device_id table to
allow proper creation of modalias strings and fix autoloading module for
this driver.
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Link: https://lore.kernel.org/r/1592962286-25752-3-git-send-email-yilun.xu@intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

The driver is expected to support device ID "spi_altera" for MMIO accessed
devices, device ID "subdev_spi_altera" for indirect accessed devices. But
the platform bus will not try driver name match anymore if the platform
driver has an id_table. So the "spi_altera" should also be added to
id_table.
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Link: https://lore.kernel.org/r/1592962286-25752-2-git-send-email-yilun.xu@intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

Add fallback pio feature in case  dma transfer failed before start.
Besides, another whole pio transfer including setup_transfer will be
issued by spi core, no need to restore jobs like commit bcd8e776 ("spi:
imx: fallback to PIO if dma setup failure").
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Link: https://lore.kernel.org/r/1592347329-28363-3-git-send-email-yibin.gong@nxp.comSigned-off-by: Mark Brown <broonie@kernel.org>

Add fallback to pio mode in case dma transfer failed with error status
SPI_TRANS_FAIL_NO_START.
If spi client driver want to enable this feature please set xfer->error in
the proper place such as dmaengine_prep_slave_sg() failure detect(but no
any data put into spi bus yet). Besides, add master->fallback checking in
its can_dma() so that spi core could switch to pio next time. Please refer
to spi-imx.c.
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Link: https://lore.kernel.org/r/1592347329-28363-2-git-send-email-yibin.gong@nxp.comSigned-off-by: Mark Brown <broonie@kernel.org>

To follow onto Doug's latest spi geni series[1] this simplifies and
reduces the code a little more.

[1] https://lore.kernel.org/r/20200618150626.237027-1-dianders@chromium.org

Stephen Boyd (2):
  spi: spi-geni-qcom: Simplify setup_fifo_xfer()
  spi: spi-geni-qcom: Don't set {tx,rx}_rem_bytes unnecessarily

 drivers/spi/spi-geni-qcom.c | 55 +++++++++++++++++--------------------
 1 file changed, 25 insertions(+), 30 deletions(-)

base-commit: 7ba9bdcb
--
Sent by a computer, using git, on the internet

We only need to test for these counters being non-zero when we see the
end of a transfer. If we're doing a CS change then they will already be
zero.  This implies that we don't need to set these to 0 if we're
cancelling an in flight transfer too, because we only care to test these
counters when the 'DONE' bit is set in the hardware and we've set them
to non-zero for a transfer.

This is a non-functional change, just cleanup to consolidate code.
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200620022233.64716-3-swboyd@chromium.orgSigned-off-by: Mark Brown <broonie@kernel.org>

The definition of SPI_FULL_DUPLEX (3) is really SPI_TX_ONLY (1) ORed
with SPI_RX_ONLY (2). Let's drop the define and simplify the code here a
bit by collapsing the setting of 'm_cmd' into conditions that are the
same.

This is a non-functional change, just cleanup to consolidate code.
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200620022233.64716-2-swboyd@chromium.orgSigned-off-by: Mark Brown <broonie@kernel.org>

The interrupt handler calls completion and is IRQ requested before the
completion is initialized.  Logically it should be the other way.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20200622110543.5035-4-krzk@kernel.orgSigned-off-by: Mark Brown <broonie@kernel.org>

If shared interrupt comes late, during probe error path or device remove
(could be triggered with CONFIG_DEBUG_SHIRQ), the interrupt handler
dspi_interrupt() will access registers with the clock being disabled.
This leads to external abort on non-linefetch on Toradex Colibri VF50
module (with Vybrid VF5xx):

    $ echo 4002d000.spi > /sys/devices/platform/soc/40000000.bus/4002d000.spi/driver/unbind

    Unhandled fault: external abort on non-linefetch (0x1008) at 0x8887f02c
    Internal error: : 1008 [#1] ARM
    Hardware name: Freescale Vybrid VF5xx/VF6xx (Device Tree)
    Backtrace:
      (regmap_mmio_read32le)
      (regmap_mmio_read)
      (_regmap_bus_reg_read)
      (_regmap_read)
      (regmap_read)
      (dspi_interrupt)
      (free_irq)
      (devm_irq_release)
      (release_nodes)
      (devres_release_all)
      (device_release_driver_internal)

The resource-managed framework should not be used for shared interrupt
handling, because the interrupt handler might be called after releasing
other resources and disabling clocks.

Similar bug could happen during suspend - the shared interrupt handler
could be invoked after suspending the device.  Each device sharing this
interrupt line should disable the IRQ during suspend so handler will be
invoked only in following cases:
1. None suspended,
2. All devices resumed.

Fixes: 349ad66c ("spi:Add Freescale DSPI driver for Vybrid VF610 platform")
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200622110543.5035-3-krzk@kernel.orgSigned-off-by: Mark Brown <broonie@kernel.org>

During shutdown, the driver should unregister the SPI controller
and stop the hardware.  Otherwise the dspi_transfer_one_message() could
wait on completion infinitely.

Additionally, calling spi_unregister_controller() first in device
shutdown reverse-matches the probe function, where SPI controller is
registered at the end.

Fixes: dc234825 ("spi: spi-fsl-dspi: Adding shutdown hook")
Reported-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200622110543.5035-2-krzk@kernel.orgSigned-off-by: Mark Brown <broonie@kernel.org>