Commit Graph

4535 Commits

Author SHA1 Message Date
Linus Torvalds 4feaab05dc LED updates for 5.4-rc1
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQUwxxKyE5l/npt8ARiEGxRG/Sl2wUCXYAIeQAKCRBiEGxRG/Sl
 2/SzAQDEnoNxzV/R5kWFd+2kmFeY3cll0d99KMrWJ8om+kje6QD/cXxZHzFm+T1L
 UPF66k76oOODV7cyndjXnTnRXbeCRAM=
 =Szby
 -----END PGP SIGNATURE-----

Merge tag 'leds-for-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds

Pull LED updates from Jacek Anaszewski:
 "In this cycle we've finally managed to contribute the patch set
  sorting out LED naming issues. Besides that there are many changes
  scattered among various LED class drivers and triggers.

  LED naming related improvements:

   - add new 'function' and 'color' fwnode properties and deprecate
     'label' property which has been frequently abused for conveying
     vendor specific names that have been available in sysfs anyway

   - introduce a set of standard LED_FUNCTION* definitions

   - introduce a set of standard LED_COLOR_ID* definitions

   - add a new {devm_}led_classdev_register_ext() API with the
     capability of automatic LED name composition basing on the
     properties available in the passed fwnode; the function is
     backwards compatible in a sense that it uses 'label' data, if
     present in the fwnode, for creating LED name

   - add tools/leds/get_led_device_info.sh script for retrieving LED
     vendor, product and bus names, if applicable; it also performs
     basic validation of an LED name

   - update following drivers and their DT bindings to use the new LED
     registration API:

        - leds-an30259a, leds-gpio, leds-as3645a, leds-aat1290, leds-cr0014114,
          leds-lm3601x, leds-lm3692x, leds-lp8860, leds-lt3593, leds-sc27xx-blt

  Other LED class improvements:

   - replace {devm_}led_classdev_register() macros with inlines

   - allow to call led_classdev_unregister() unconditionally

   - switch to use fwnode instead of be stuck with OF one

  LED triggers improvements:

   - led-triggers:
        - fix dereferencing of null pointer
        - fix a memory leak bug

   - ledtrig-gpio:
        - GPIO 0 is valid

  Drop superseeded apu2/3 support from leds-apu since for apu2+ a newer,
  more complete driver exists, based on a generic driver for the AMD
  SOCs gpio-controller, supporting LEDs as well other devices:

   - drop profile field from priv data

   - drop iosize field from priv data

   - drop enum_apu_led_platform_types

   - drop superseeded apu2/3 led support

   - add pr_fmt prefix for better log output

   - fix error message on probing failure

  Other misc fixes and improvements to existing LED class drivers:

   - leds-ns2, leds-max77650:
        - add of_node_put() before return

   - leds-pwm, leds-is31fl32xx:
        - use struct_size() helper

   - leds-lm3697, leds-lm36274, leds-lm3532:
        - switch to use fwnode_property_count_uXX()

   - leds-lm3532:
        - fix brightness control for i2c mode
        - change the define for the fs current register
        - fixes for the driver for stability
        - add full scale current configuration
        - dt: Add property for full scale current.
        - avoid potentially unpaired regulator calls
        - move static keyword to the front of declarations
        - fix optional led-max-microamp prop error handling

   - leds-max77650:
        - add of_node_put() before return
        - add MODULE_ALIAS()
        - Switch to fwnode property API

   - leds-as3645a:
        - fix misuse of strlcpy

   - leds-netxbig:
        - add of_node_put() in netxbig_leds_get_of_pdata()
        - remove legacy board-file support

   - leds-is31fl319x:
        - simplify getting the adapter of a client

   - leds-ti-lmu-common:
        - fix coccinelle issue
        - move static keyword to the front of declaration

   - leds-syscon:
        - use resource managed variant of device register

   - leds-ktd2692:
        - fix a typo in the name of a constant

   - leds-lp5562:
        - allow firmware files up to the maximum length

   - leds-an30259a:
        - fix typo

   - leds-pca953x:
        - include the right header"

* tag 'leds-for-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds: (72 commits)
  leds: lm3532: Fix optional led-max-microamp prop error handling
  led: triggers: Fix dereferencing of null pointer
  leds: ti-lmu-common: Move static keyword to the front of declaration
  leds: lm3532: Move static keyword to the front of declarations
  leds: trigger: gpio: GPIO 0 is valid
  leds: pwm: Use struct_size() helper
  leds: is31fl32xx: Use struct_size() helper
  leds: ti-lmu-common: Fix coccinelle issue in TI LMU
  leds: lm3532: Avoid potentially unpaired regulator calls
  leds: syscon: Use resource managed variant of device register
  leds: Replace {devm_}led_classdev_register() macros with inlines
  leds: Allow to call led_classdev_unregister() unconditionally
  leds: lm3532: Add full scale current configuration
  dt: lm3532: Add property for full scale current.
  leds: lm3532: Fixes for the driver for stability
  leds: lm3532: Change the define for the fs current register
  leds: lm3532: Fix brightness control for i2c mode
  leds: Switch to use fwnode instead of be stuck with OF one
  leds: max77650: Switch to fwnode property API
  led: triggers: Fix a memory leak bug
  ...
2019-09-17 18:40:42 -07:00
Linus Torvalds 7c672abc12 It's a somewhat calmer cycle for docs this time, as the churn of the mass
RST conversion is happily mostly behind us.
 
  - A new document on reproducible builds.
 
  - We finally got around to zapping the documentation for hardware support
    that was removed in 2004; one doesn't want to rush these things.
 
  - The usual assortment of fixes, typo corrections, etc.
 
 You'll still find a handful of annoying conflicts against other trees,
 mostly tied to the last RST conversions; resolutions are straightforward
 and the linux-next ones are good.
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCAAdFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAl1/J4IACgkQF0NaE2wM
 flhYogf9EgYozCe8RocSq+JjJpZOSFjIGDQv+GwTjOBIdqgO9tSIaY/p0wSkYKil
 jYXyMDF+Xwr8podsUep2F7akBM7j9XJ+XBGJcfOna0ypC9xoejMgWt9fU3YvaWge
 dQJxIQ/iwkDlKNx6uOYgKysLUWFS0EP/nzPhqBo4bZZzhugvrR46D/nQqFNmGihd
 l9yLalJtP5mC0XRUv3hpdAFFFKxdC0R3BGOel2V+slSClp0LEgpdMAuMaKydEDI3
 Ch9ZpIp8fB8kqONCs9/X6083WRsDOMe28KgeGrGHo4Jla6u51QBLQjSVKttFv7xk
 051yNJwDWMxgl+A4gyNLDPXM7Gd7HQ==
 =v4dp
 -----END PGP SIGNATURE-----

Merge tag 'docs-5.4' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "It's a somewhat calmer cycle for docs this time, as the churn of the
  mass RST conversion is happily mostly behind us.

   - A new document on reproducible builds.

   - We finally got around to zapping the documentation for hardware
     support that was removed in 2004; one doesn't want to rush these
     things.

   - The usual assortment of fixes, typo corrections, etc"

* tag 'docs-5.4' of git://git.lwn.net/linux: (67 commits)
  Documentation: kbuild: Add document about reproducible builds
  docs: printk-formats: Stop encouraging use of unnecessary %h[xudi] and %hh[xudi]
  Documentation: Add "earlycon=sbi" to the admin guide
  doc🔒 remove reference to clever use of read-write lock
  devices.txt: improve entry for comedi (char major 98)
  docs: mtd: Update spi nor reference driver
  doc: arm64: fix grammar dtb placed in no attributes region
  Documentation: sysrq: don't recommend 'S' 'U' before 'B'
  mailmap: Update email address for Quentin Perret
  docs: ftrace: clarify when tracing is disabled by the trace file
  docs: process: fix broken link
  Documentation/arm/samsung-s3c24xx: Remove stray U+FEFF character to fix title
  Documentation/arm/sa1100/assabet: Fix 'make assabet_defconfig' command
  Documentation/arm/sa1100: Remove some obsolete documentation
  docs/zh_CN: update Chinese howto.rst for latexdocs making
  Documentation: virt: Fix broken reference to virt tree's index
  docs: Fix typo on pull requests guide
  kernel-doc: Allow anonymous enum
  Documentation: sphinx: Don't parse socket() as identifier reference
  Documentation: sphinx: Add missing comma to list of strings
  ...
2019-09-17 16:22:26 -07:00
Linus Torvalds 399eb9b6cb ARM: SoC driver updates for v5.4
The branch contains driver changes that are tightly
 connected to SoC specific code. Aside from smaller
 cleanups and bug fixes, here is a list of the notable
 changes.
 
 New device drivers:
 
 - The Turris Mox router has a new "moxtet" bus driver
   for its on-board pluggable extension bus. The
   same platform also gains a firmware driver.
 
 - The Samsung Exynos family gains a new Chipid driver
   exporting using the soc device sysfs interface
 
 - A similar socinfo driver for Qualcomm Snapdragon
   chips.
 
 - A firmware driver for the NXP i.MX DSP IPC protocol
   using shared memory and a mailbox
 
 Other changes:
 
 - The i.MX reset controller driver now supports the
   NXP i.MX8MM chip
 
 - Amlogic SoC specific drivers gain support for
   the S905X3 and A311D chips
 
 - A rework of the TI Davinci framebuffer driver to
   allow important cleanups in the platform code
 
 - A couple of device drivers for removed ARM SoC
   platforms are removed. Most of the removals were
   picked up by other maintainers, this contains
   whatever was left.
 
 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABCAAGBQJdf6SUAAoJEJpsee/mABjZAfwP/01bXBOlGVusNH2zuh8IUSHb
 //5sTdWpwa2ugRekLOJUOjo2p9Fu70yH6xr4RUHI0rcRjZA0xR3bZPx45gI8LRHQ
 tfb25LaKqfgZjWMCJ8due1Lh7B6ffOQukryMtM/LoiCtqsy7b6aThEKaLpM9/Owl
 t53o4wKaVQJK5He9JQom9NOZidkl7tYLHmDQTOXhX2UEA/i45vtfjdsEBvoFPbTx
 +bYvlqs+SWlpDJk29j+oBOeKadPF+TFboLDiUCxH44MC3OsH51zjtKVBRTtbNMkb
 ek/ci5x9hCeHcYSEigNq2EMzEln09Yxyvjk8U/jLiJ1h1kz3p5MjqJbVMF1rYXpe
 ALuAwinM8Zv2o5/UOCkiQTWq79PtpOKHZKpNBXkaJ8kyqBLMSy8Fs3hCvXrDnjnQ
 TC8jX7UBqHRV2rbQIYehAQAxTvcRgTbqusQGLkUJInlux6go57LoMYHPABpHftJV
 kRdVeT0KzdCz1pvQwyekIog5hPLNTBi4jw6eQcOgeENvAea1MJa8lMMfKcVbIdS0
 ZVvxLl+K6noEKAv5lSeHAzjXq+cQFr3zDCsWy351mJETDHmE8zjsaHN1SgbRYLEk
 ZqzNwUYaPYBis38g85qaY/TSsJrWJ+jP8u7s9HTw3Oywg8SRy5vtW177s00/9VOd
 PYZ2UpqUeX8cdvggqUUU
 =lxFi
 -----END PGP SIGNATURE-----

Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

Pull ARM SoC driver updates from Arnd Bergmann:
 "This contains driver changes that are tightly connected to SoC
  specific code. Aside from smaller cleanups and bug fixes, here is a
  list of the notable changes.

  New device drivers:

   - The Turris Mox router has a new "moxtet" bus driver for its
     on-board pluggable extension bus. The same platform also gains a
     firmware driver.

   - The Samsung Exynos family gains a new Chipid driver exporting using
     the soc device sysfs interface

   - A similar socinfo driver for Qualcomm Snapdragon chips.

   - A firmware driver for the NXP i.MX DSP IPC protocol using shared
     memory and a mailbox

  Other changes:

   - The i.MX reset controller driver now supports the NXP i.MX8MM chip

   - Amlogic SoC specific drivers gain support for the S905X3 and A311D
     chips

   - A rework of the TI Davinci framebuffer driver to allow important
     cleanups in the platform code

   - A couple of device drivers for removed ARM SoC platforms are
     removed. Most of the removals were picked up by other maintainers,
     this contains whatever was left"

* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (123 commits)
  bus: uniphier-system-bus: use devm_platform_ioremap_resource()
  soc: ti: ti_sci_pm_domains: Add support for exclusive and shared access
  dt-bindings: ti_sci_pm_domains: Add support for exclusive and shared access
  firmware: ti_sci: Allow for device shared and exclusive requests
  bus: imx-weim: remove incorrect __init annotations
  fbdev: remove w90x900/nuc900 platform drivers
  spi: remove w90x900 driver
  net: remove w90p910-ether driver
  net: remove ks8695 driver
  firmware: turris-mox-rwtm: Add sysfs documentation
  firmware: Add Turris Mox rWTM firmware driver
  dt-bindings: firmware: Document cznic,turris-mox-rwtm binding
  bus: moxtet: fix unsigned comparison to less than zero
  bus: moxtet: remove set but not used variable 'dummy'
  ARM: scoop: Use the right include
  dt-bindings: power: add Amlogic Everything-Else power domains bindings
  soc: amlogic: Add support for Everything-Else power domains controller
  fbdev: da8xx: use resource management for dma
  fbdev: da8xx-fb: drop a redundant if
  fbdev: da8xx-fb: use devm_platform_ioremap_resource()
  ...
2019-09-16 15:52:38 -07:00
Mark Brown b769c5ba8a
Merge branch 'spi-5.4' into spi-next 2019-09-15 10:32:06 +01:00
Mark Brown 262a2f3345
Merge branch 'spi-5.3' into spi-linus 2019-09-15 10:32:04 +01:00
luhua.xu fdeae8f5a2
spi: mediatek: support large PA
Add spi large PA(max=64G) support for DMA transfer.

Signed-off-by: luhua.xu <luhua.xu@mediatek.com>
Link: https://lore.kernel.org/r/1568195731-3239-4-git-send-email-luhua.xu@mediatek.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-13 10:41:10 +01:00
luhua.xu 2c231e0ab6
spi: mediatek: add spi support for mt6765 IC
This patch add spi support for mt6765 IC.

Signed-off-by: luhua.xu <luhua.xu@mediatek.com>
Link: https://lore.kernel.org/r/1568195731-3239-3-git-send-email-luhua.xu@mediatek.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-13 10:40:37 +01:00
Lukas Wunner 2b8279aec1
spi: bcm2835: Speed up RX-only DMA transfers by zero-filling TX FIFO
The BCM2835 SPI driver currently sets the SPI_CONTROLLER_MUST_TX flag.
When performing an RX-only transfer, this flag causes the SPI core to
allocate and DMA-map a dummy buffer which is copied to the TX FIFO.
The dummy buffer is necessary because the chip is not capable of
automatically clocking out null bytes.

Avoid the overhead induced by the dummy buffer by preallocating a
reusable DMA transaction which fills the TX FIFO by cyclically copying
from the zero page.  The transaction requires very little CPU time to
submit and generates no interrupts while running.  Specifics are
provided in kerneldoc comments.

[Nathan Chancellor contributed a DMA mapping fixup for an early version
of this commit, hence his Signed-off-by.]

Tested-by: Nuno Sá <nuno.sa@analog.com>
Tested-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Stefan Wahren <wahrenst@gmx.net>
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Link: https://lore.kernel.org/r/f45920af18dbf06e34129bbc406f53dc9c5d1075.1568187525.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-11 15:57:46 +01:00
Lukas Wunner 8259bf667a
spi: bcm2835: Speed up TX-only DMA transfers by clearing RX FIFO
The BCM2835 SPI driver currently sets the SPI_CONTROLLER_MUST_RX flag.
When performing a TX-only transfer, this flag causes the SPI core to
allocate and DMA-map a dummy buffer into which the RX FIFO contents are
copied.  The dummy buffer is necessary because the chip is not capable
of disabling the receiver or automatically throwing away received data.
Not reading the RX FIFO isn't an option either since transmission is
halted once it's full.

Avoid the overhead induced by the dummy buffer by preallocating a
reusable DMA transaction which cyclically clears the RX FIFO.  The
transaction requires very little CPU time to submit and generates no
interrupts while running.  Specifics are provided in kerneldoc comments.

With a ks8851 Ethernet chip attached to the SPI controller, I am seeing
a 30 us reduction in ping time with this commit (1.819 ms vs. 1.849 ms,
average of 100,000 packets) as well as a 2% reduction in CPU time
(75:08 vs. 76:39 for transmission of 5 GByte over the SPI bus).

The commit uses the TX DMA interrupt to signal completion of a transfer.
This interrupt is raised once all bytes have been written to the
TX FIFO and it is then necessary to busy-wait for the TX FIFO to become
empty before the transfer can be finalized.  As an alternative approach,
I have explored using the SPI controller's DONE interrupt to detect
completion.  This interrupt is signaled when the TX FIFO becomes empty,
avoiding the need to busy-wait.  However latency deteriorates compared
to the present commit and surprisingly, CPU time is slightly higher as
well:

It turns out that in 45% of the cases, no busy-waiting is needed at all
and in 76% of the cases, less than 10 busy-wait iterations are
sufficient for the TX FIFO to drain.  This was measured on an RT kernel.
On a vanilla kernel, wakeup latency is worse and thus fewer iterations
are needed.  The measurements were made with an SPI clock of 20 MHz,
they may differ slightly for slower or faster clock speeds.

Previously we always used the RX DMA interrupt to signal completion of a
transfer.  Using the TX DMA interrupt now introduces a race condition:
TX DMA is always started before RX DMA so that bytes are already clocked
out while RX DMA is still being set up.  But if a TX-only transfer is
very short, then the TX DMA interrupt may occur before RX DMA is set up.
If the interrupt happens to occur on the same CPU, setup of RX DMA may
even be delayed until after the interrupt was handled.

I've solved this by having the TX DMA callback clear the RX FIFO while
busy-waiting for the TX FIFO to drain, thus avoiding a dependency on
setup of RX DMA.  Additionally, I am using a lock-free mechanism with
two flags, tx_dma_active and rx_dma_active plus memory barriers to
terminate RX DMA either by the TX DMA callback or immediately after
setting it up, whichever wins the race.  I've explored an alternative
approach which temporarily disables the TX DMA callback until RX DMA
has been set up (using tasklet_disable(), local_bh_disable() or
local_irq_save()), but the performance was minimally worse.

[Nathan Chancellor contributed a DMA mapping fixup for an early version
of this commit, hence his Signed-off-by.]

Tested-by: Nuno Sá <nuno.sa@analog.com>
Tested-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Stefan Wahren <wahrenst@gmx.net>
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Link: https://lore.kernel.org/r/874949385f28251e2dcaa9494e39a27b50e9f9e4.1568187525.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-11 15:57:30 +01:00
Lukas Wunner 571e31fa60
spi: bcm2835: Cache CS register value for ->prepare_message()
The BCM2835 SPI driver needs to set up the clock polarity in its
->prepare_message() hook before spi_transfer_one_message() asserts chip
select to avoid a gratuitous clock signal edge (cf. commit acace73df2
("spi: bcm2835: set up spi-mode before asserting cs-gpio")).

Precalculate the CS register value (which selects the clock polarity)
once in ->setup() and use that cached value in ->prepare_message() and
->transfer_one().  This avoids one MMIO read per message and one per
transfer, yielding a small latency improvement.  Additionally, a
forthcoming commit will use the precalculated value to derive the
register value for clearing the RX FIFO, which will eliminate the need
for an RX dummy buffer when performing TX-only DMA transfers.

Tested-by: Nuno Sá <nuno.sa@analog.com>
Tested-by: Noralf Trønnes <noralf@tronnes.org>
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/d17c1d7fcdc97fffa961b8737cfd80eeb14f9416.1568187525.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-11 15:56:30 +01:00
Lukas Wunner 229e6af102
spi: Guarantee cacheline alignment of driver-private data
__spi_alloc_controller() uses a single allocation to accommodate struct
spi_controller and the driver-private data, but places the latter behind
the former.  This order does not guarantee cacheline alignment of the
driver-private data.  (It does guarantee cacheline alignment of struct
spi_controller but the structure doesn't make any use of that property.)

Round up struct spi_controller to cacheline size.  A forthcoming commit
leverages this to grant DMA access to driver-private data of the BCM2835
SPI master.

An alternative, less economical approach would be to use two allocations.

A third approach consists of reversing the order to conserve memory.
But Mark Brown is concerned that it may result in a performance penalty
on architectures that don't like unaligned accesses.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/01625b9b26b93417fb09d2c15ad02dfe9cdbbbe5.1568187525.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-11 15:53:11 +01:00
Lukas Wunner 1513ceee70
spi: bcm2835: Drop dma_pending flag
The BCM2835 SPI driver uses a flag to keep track of whether a DMA
transfer is in progress.

The flag is used to avoid terminating DMA channels multiple times if a
transfer finishes orderly while simultaneously the SPI core invokes the
->handle_err() callback because the transfer took too long.  However
terminating DMA channels multiple times is perfectly fine, so the flag
is unnecessary for this particular purpose.

The flag is also used to avoid invoking bcm2835_spi_undo_prologue()
multiple times under this race condition.  However multiple *concurrent*
invocations can no longer happen since commit 2527704d84 ("spi:
bcm2835: Synchronize with callback on DMA termination") because the
->handle_err() callback now uses the _sync() variant when terminating
DMA channels.

The only raison d'être of the flag is therefore that
bcm2835_spi_undo_prologue() cannot cope with multiple *sequential*
invocations.  Achieve that by setting tx_prologue to 0 at the end of
the function.  Subsequent invocations thus become no-ops.

With that, the dma_pending flag becomes unnecessary, so drop it.

Tested-by: Nuno Sá <nuno.sa@analog.com>
Tested-by: Noralf Trønnes <noralf@tronnes.org>
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/062b03b7f86af77a13ce0ec3b22e0bdbfcfba10d.1568187525.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-11 15:52:33 +01:00
Lukas Wunner 4c524191c0
spi: bcm2835: Work around DONE bit erratum
Commit 3bd7f6589f ("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>
2019-09-10 11:28:44 +01:00
Markus Elfring 8995673e6f
spi-gpio: Use PTR_ERR_OR_ZERO() in spi_gpio_request()
Simplify this function implementation by using a known function.

Generated by: scripts/coccinelle/api/ptr_ret.cocci

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/b2dd074a-1693-3aea-42b4-da1f5ec155c4@web.de
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-09 11:05:39 +01:00
Vladimir Oltean d1c44c9342
spi: Use an abbreviated pointer to ctlr->cur_msg in __spi_pump_messages
This helps a bit with line fitting now (the list_first_entry call) as
well as during the next patch which needs to iterate through all
transfers of ctlr->cur_msg so it timestamps them.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190905010114.26718-2-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-05 18:20:12 +01:00
YueHaibing a0ce1fd11e
spi: npcm-fiu: remove set but not used variable 'retlen'
drivers/spi/spi-npcm-fiu.c: In function npcm_fiu_read:
drivers/spi/spi-npcm-fiu.c:472:9: warning:
 variable retlen set but not used [-Wunused-but-set-variable]

It is never used, so remove it.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190905072436.23932-1-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-05 18:19:45 +01:00
YueHaibing 43a5baa6d8
spi: fsl-spi: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-37-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:24:26 +01:00
YueHaibing ae91a439ac
spi: zynq-qspi: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-36-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:24:07 +01:00
YueHaibing 214d1edb60
spi: zynqmp: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-35-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:23:48 +01:00
YueHaibing 7734829307
spi: xlp: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-34-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:23:28 +01:00
YueHaibing 755f1a2500
spi: uniphier: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-33-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:23:08 +01:00
YueHaibing e8d63b38b1
spi: tegra: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-32-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:22:58 +01:00
YueHaibing 7c7c31f7f9
spi: sun6i: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-31-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:22:49 +01:00
YueHaibing 8c649f4d4e
spi: sun4i: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-30-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:22:29 +01:00
YueHaibing 338dd352ac
spi: st-ssc4: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-29-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:22:10 +01:00
YueHaibing a755008377
spi: sirf: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-28-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:22:00 +01:00
YueHaibing fa79f20047
spi: sifive: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-27-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:21:41 +01:00
YueHaibing b38f1f9b6e
spi: s3c24xx: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-26-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:21:31 +01:00
YueHaibing 7d4c208326
spi: rb4xx: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-25-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:21:21 +01:00
YueHaibing e0ea3cc2ba
spi: spi-qcom-qspi: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-24-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:21:12 +01:00
YueHaibing e751032bcb
spi: pic32-sqi: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-23-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:20:52 +01:00
YueHaibing f601a654bb
spi: oc-tiny: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-22-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:20:33 +01:00
YueHaibing 4c6f537a03
spi: nuc900: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-21-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:20:23 +01:00
YueHaibing dcbceb6de0
spi: npcm: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-20-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:20:03 +01:00
YueHaibing d4225b3665
spi: mxs: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-19-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:19:54 +01:00
YueHaibing f88771ca71
spi: mt7621: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-18-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:19:34 +01:00
YueHaibing 425aa308a2
spi: spi-meson-spifc: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20190904135918.25352-17-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:19:14 +01:00
YueHaibing 362385c045
spi: meson-spicc: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20190904135918.25352-16-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:18:55 +01:00
YueHaibing 7d2600b9cc
spi: lp-8841: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-15-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:18:35 +01:00
YueHaibing d8e477abec
spi: spi-geni-qcom: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-14-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:18:25 +01:00
YueHaibing 5cc6fdccbb
spi: dw-mmio: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-13-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:18:05 +01:00
YueHaibing 1e2d65d06d
spi: coldfire-qspi: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-12-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:17:56 +01:00
YueHaibing ae43724d64
spi: clps711x: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-11-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:17:36 +01:00
YueHaibing 050688dc72
spi: octeon: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-10-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:17:27 +01:00
YueHaibing 4585bb92a5
spi: cadence: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-9-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:17:07 +01:00
YueHaibing e364c8c204
spi: bcm63xx-hsspi: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-8-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:16:47 +01:00
YueHaibing 6ba794dfbb
spi: bcm2835: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-7-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:16:28 +01:00
YueHaibing d1975d0596
spi: bcm2835aux: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-6-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:16:08 +01:00
YueHaibing 7d6a5e2b17
spi: spi-axi: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-5-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:15:49 +01:00
YueHaibing bf3484190f
spi: ath79: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-4-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:15:29 +01:00