Eric Lee / smarc-fsl-linux-kernel

14 Nov, 2020

1 commit

  • d853b3406   spi: bcm2835aux: Restore err assignment in bcm2835aux_spi_probe ... Browse Code »

    Clang warns:

    drivers/spi/spi-bcm2835aux.c:532:50: warning: variable 'err' is
    uninitialized when used here [-Wuninitialized]
    dev_err(&pdev->dev, "could not get clk: %d\n", err);
    ^~~
    ./include/linux/dev_printk.h:112:32: note: expanded from macro 'dev_err'
    _dev_err(dev, dev_fmt(fmt), ##__VA_ARGS__)
    ^~~~~~~~~~~
    drivers/spi/spi-bcm2835aux.c:495:9: note: initialize the variable 'err'
    to silence this warning
    int err;
    ^
    = 0
    1 warning generated.

    Restore the assignment so that the error value can be used in the
    dev_err statement and there is no uninitialized memory being leaked.

    Fixes: e13ee6cc4781 ("spi: bcm2835aux: Fix use-after-free on unbind")
    Link: https://github.com/ClangBuiltLinux/linux/issues/1199
    Signed-off-by: Nathan Chancellor
    Link: https://lore.kernel.org/r/20201113180701.455541-1-natechancellor@gmail.com
    Signed-off-by: Mark Brown

    Nathan Chancellor
     

12 Nov, 2020

1 commit

  • e13ee6cc4   spi: bcm2835aux: Fix use-after-free on unbind ... Browse Code »

    bcm2835aux_spi_remove() accesses the driver's private data after calling
    spi_unregister_master() even though that function releases the last
    reference on the spi_master and thereby frees the private data.

    Fix by switching over to the new devm_spi_alloc_master() helper which
    keeps the private data accessible until the driver has unbound.

    Fixes: b9dd3f6d4172 ("spi: bcm2835aux: Fix controller unregister order")
    Signed-off-by: Lukas Wunner
    Cc: # v4.4+: 123456789abc: spi: Introduce device-managed SPI controller allocation
    Cc: # v4.4+: b9dd3f6d4172: spi: bcm2835aux: Fix controller unregister order
    Cc: # v4.4+
    Link: https://lore.kernel.org/r/b290b06357d0c0bdee9cecc539b840a90630f101.1605121038.git.lukas@wunner.de
    Signed-off-by: Mark Brown

    Lukas Wunner
     

24 Aug, 2020

1 commit

  • df561f668   treewide: Use fallthrough pseudo-keyword ... Browse Code »

    Replace the existing /* fall through */ comments and its variants with
    the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
    fall-through markings when it is the case.

    [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

    Signed-off-by: Gustavo A. R. Silva

    Gustavo A. R. Silva
     

17 Jul, 2020

1 commit

  • 5e94c3cda   spi: bcm2835aux: support effective_speed_hz ... Browse Code »

    Setting spi_transfer->effective_speed_hz in transfer_one so that
    it can get used in cs_change_delay configured with delay as a muliple
    of SPI clock cycles.

    Signed-off-by: Martin Sperl
    Signed-off-by: Marc Kleine-Budde
    Link: https://lore.kernel.org/r/20200709074120.110069-3-mkl@pengutronix.de
    Signed-off-by: Mark Brown

    Martin Sperl
     

20 May, 2020

1 commit

  • b9dd3f6d4   spi: bcm2835aux: Fix controller unregister order ... Browse Code »

    The BCM2835aux SPI driver uses devm_spi_register_master() on bind.
    As a consequence, on unbind, __device_release_driver() first invokes
    bcm2835aux_spi_remove() before unregistering the SPI controller via
    devres_release_all().

    This order is incorrect: bcm2835aux_spi_remove() turns off the SPI
    controller, including its interrupts and clock. The SPI controller
    is thus no longer usable.

    When the SPI controller is subsequently unregistered, it unbinds all
    its slave devices. If their drivers need to access the SPI bus,
    e.g. to quiesce their interrupts, unbinding will fail.

    As a rule, devm_spi_register_master() must not be used if the
    ->remove() hook performs teardown steps which shall be performed
    after unbinding of slaves.

    Fix by using the non-devm variant spi_register_master(). Note that the
    struct spi_master as well as the driver-private data are not freed until
    after bcm2835aux_spi_remove() has finished, so accessing them is safe.

    Fixes: 1ea29b39f4c8 ("spi: bcm2835aux: add bcm2835 auxiliary spi device driver")
    Signed-off-by: Lukas Wunner
    Cc: stable@vger.kernel.org # v4.4+
    Cc: Martin Sperl
    Link: https://lore.kernel.org/r/32f27f4d8242e4d75f9a53f7e8f1f77483b08669.1589557526.git.lukas@wunner.de
    Signed-off-by: Mark Brown

    Lukas Wunner
     

05 Sep, 2019

1 commit

02 Aug, 2019

1 commit

  • 6b8ac10e0   spi: Remove dev_err() usage after platform_get_irq() ... Browse Code »

    We don't need dev_err() messages when platform_get_irq() fails now that
    platform_get_irq() prints an error message itself when something goes
    wrong. Let's remove these prints with a simple semantic patch.

    //
    @@
    expression ret;
    struct platform_device *E;
    @@

    ret =
    (
    platform_get_irq(E, ...)
    |
    platform_get_irq_byname(E, ...)
    );

    if ( \( ret < 0 \| ret

    While we're here, remove braces on if statements that only have one
    statement (manually).

    Cc: Mark Brown
    Cc: linux-spi@vger.kernel.org
    Cc: Greg Kroah-Hartman
    Signed-off-by: Stephen Boyd
    Link: https://lore.kernel.org/r/20190730181557.90391-42-swboyd@chromium.org
    Signed-off-by: Mark Brown

    Stephen Boyd
     

11 Jun, 2019

1 commit

31 May, 2019

1 commit

  • c942fddf8   treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 ... Browse Code »

    Based on 3 normalized pattern(s):

    this program is free software you can redistribute it and or modify
    it under the terms of the gnu general public license as published by
    the free software foundation either version 2 of the license or at
    your option any later version this program is distributed in the
    hope that it will be useful but without any warranty without even
    the implied warranty of merchantability or fitness for a particular
    purpose see the gnu general public license for more details

    this program is free software you can redistribute it and or modify
    it under the terms of the gnu general public license as published by
    the free software foundation either version 2 of the license or at
    your option any later version [author] [kishon] [vijay] [abraham]
    [i] [kishon]@[ti] [com] this program is distributed in the hope that
    it will be useful but without any warranty without even the implied
    warranty of merchantability or fitness for a particular purpose see
    the gnu general public license for more details

    this program is free software you can redistribute it and or modify
    it under the terms of the gnu general public license as published by
    the free software foundation either version 2 of the license or at
    your option any later version [author] [graeme] [gregory]
    [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
    [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
    [hk] [hemahk]@[ti] [com] this program is distributed in the hope
    that it will be useful but without any warranty without even the
    implied warranty of merchantability or fitness for a particular
    purpose see the gnu general public license for more details

    extracted by the scancode license scanner the SPDX license identifier

    GPL-2.0-or-later

    has been chosen to replace the boilerplate/reference in 1105 file(s).

    Signed-off-by: Thomas Gleixner
    Reviewed-by: Allison Randal
    Reviewed-by: Richard Fontana
    Reviewed-by: Kate Stewart
    Cc: linux-spdx@vger.kernel.org
    Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
    Signed-off-by: Greg Kroah-Hartman

    Thomas Gleixner
     

13 May, 2019

1 commit

08 Apr, 2019

1 commit

  • 9b186e9a6   spi: bcm2835aux: Fix build error without CONFIG_DEBUG_FS ... Browse Code »

    When building CONFIG_DEBUG_FS is not set
    gcc warn this:

    drivers/spi/spi-bcm2835aux.c: In function bcm2835aux_spi_probe:
    drivers/spi/spi-bcm2835aux.c:591:2: error: too many arguments to function bcm2835aux_debugfs_create
    bcm2835aux_debugfs_create(bs, dev_name(&pdev->dev));
    ^~~~~~~~~~~~~~~~~~~~~~~~~
    drivers/spi/spi-bcm2835aux.c:145:13: note: declared here
    static void bcm2835aux_debugfs_create(struct bcm2835aux_spi *bs)

    Reported-by: Hulk Robot
    Fixes: 8048d151eb4d ("spi: bcm2835aux: add driver stats to debugfs")
    Signed-off-by: YueHaibing
    Reviewed-by: Mukesh Ojha
    Signed-off-by: Mark Brown

    YueHaibing
     

04 Apr, 2019

1 commit

03 Apr, 2019

9 commits

  • 8048d151e   spi: bcm2835aux: add driver stats to debugfs ... Browse Code »

    To estimate efficiency add statistics on transfer types
    (polling and interrupt) used to debugfs.

    Signed-off-by: Martin Sperl
    Signed-off-by: Mark Brown

    Martin Sperl
     
  • 5fd917afc   spi: bcm2835aux: make the polling duration limits configurable ... Browse Code »

    Under some circumstances the default 30 us polling limit is not optimal
    and may lead to long delays because we are waiting on an interrupt.
    with this patch we have the possibility to influence this policy.

    So make this limit (in us) configurable via a module parameters
    (but also modifyable via /sys/modules/...)

    Signed-off-by: Martin Sperl
    Acked-by: Stefan Wahren
    Signed-off-by: Mark Brown

    Martin Sperl
     
  • ccd978b70   spi: bcm2835aux: setup gpio-cs to output and correct level during setup ... Browse Code »

    Setup gpio-cs to the correct levels during setup and also make the
    gpio definitely an output GPIO.

    This is transparently fixing some badly configured DTs in the process
    where cs-gpio is set but the gpios are still configured with native cs.

    It also makes 100% sure that the initial CS levels are as expected -
    especially on systems with devices on a bus with mixed CS_HIGH/CS_LOW
    settings.

    Fixes: 1ea29b39f4c812ec ("spi: bcm2835aux: add bcm2835 auxiliary spi device...")
    Signed-off-by: Martin Sperl
    Acked-by: Stefan Wahren
    Signed-off-by: Mark Brown

    Martin Sperl
     
  • 519f2c22a   spi: bcm2835aux: warn in dmesg that native cs is not really supported ... Browse Code »

    From personal bad experience (even as the author of the original driver)
    it shows that native-cs is "somewhat" supported by the spi bus driver
    when using a buggy device tree.

    So make sure that the driver is warning in dmesg about this fact
    that we are running in a not supported mode that may have surprizing
    limitations.

    Fixes: 1ea29b39f4c812ec ("spi: bcm2835aux: add bcm2835 auxiliary spi device...")
    Signed-off-by: Martin Sperl
    Acked-by: Stefan Wahren
    Signed-off-by: Mark Brown

    Martin Sperl
     
  • 509c58362   spi: bcm2835aux: fix driver to not allow 65535 (=-1) cs-gpios ... Browse Code »

    The original driver by default defines num_chipselects as -1.
    This actually allicates an array of 65535 entries in
    of_spi_register_master.

    There is a side-effect for buggy device trees that (contrary to
    dt-binding documentation) have no cs-gpio defined.

    This mode was never supported by the driver due to limitations
    of native cs and additional code complexity and is explicitly
    not stated to be implemented.

    To keep backwards compatibility with such buggy DTs we limit
    the number of chip_selects to 1, as for all practical purposes
    it is only ever realistic to use a single chip select in
    native cs mode without negative side-effects.

    Fixes: 1ea29b39f4c812ec ("spi: bcm2835aux: add bcm2835 auxiliary spi device...")
    Signed-off-by: Martin Sperl
    Acked-by: Stefan Wahren
    Signed-off-by: Mark Brown

    Martin Sperl
     
  • 08a854950   spi: bcm2835aux: remove dead code ... Browse Code »

    Remove dead code that never can get reached, as we limit count to
    a max of 3.

    Suggested-by: Hubert Denkmair
    Signed-off-by: Martin Sperl
    Acked-by: Stefan Wahren
    Signed-off-by: Mark Brown

    Martin Sperl
     
  • 73b114ee7   spi: bcm2835aux: fix corruptions for longer spi transfers ... Browse Code »

    On long running tests with a mcp2517fd can controller it showed that
    on rare occations the data read shows corruptions for longer spi transfers.

    Example of a 22 byte transfer:

    expected (as captured on logic analyzer):
    FF FF 78 00 00 00 08 06 00 00 91 20 77 56 84 85 86 87 88 89 8a 8b

    read by the driver:
    FF FF 78 00 00 00 08 06 00 00 91 20 77 56 84 88 89 8a 00 00 8b 9b

    To fix this use BCM2835_AUX_SPI_STAT_RX_LVL to determine when we may
    read data from the fifo reliably without any corruption.

    Surprisingly the only values ever empirically read in
    BCM2835_AUX_SPI_STAT_RX_LVL are 0x00, 0x10, 0x20 and 0x30.
    So whenever the mask is not 0 we can read from the fifo in a safe manner.

    The patch has now been tested intensively and we are no longer
    able to reproduce the "RX" issue any longer.

    Fixes: 1ea29b39f4c812ec ("spi: bcm2835aux: add bcm2835 auxiliary spi device...")
    Reported-by: Hubert Denkmair
    Signed-off-by: Martin Sperl
    Acked-by: Stefan Wahren
    Signed-off-by: Mark Brown

    Martin Sperl
     
  • c7de8500f   spi: bcm2835aux: remove dangerous uncontrolled read of fifo ... Browse Code »

    This read of the fifo is a potential candidate for a race condition
    as the spi transfer is not necessarily finished and so can lead to
    an early read of the fifo that still misses data.

    So it has been removed.

    Fixes: 1ea29b39f4c812ec ("spi: bcm2835aux: add bcm2835 auxiliary spi device...")
    Suggested-by: Hubert Denkmair
    Signed-off-by: Martin Sperl
    Acked-by: Stefan Wahren
    Signed-off-by: Mark Brown

    Martin Sperl
     
  • 7188a6f0e   spi: bcm2835aux: unifying code between polling and interrupt driven code ... Browse Code »

    Sharing more code between polling and interrupt-driven mode.

    Signed-off-by: Martin Sperl
    Acked-by: Stefan Wahren
    Signed-off-by: Mark Brown

    Martin Sperl
     

23 Jan, 2019

1 commit

15 Nov, 2018

1 commit

04 May, 2018

1 commit

  • bc519d957   spi: bcm2835aux: ensure interrupts are enabled for shared handler ... Browse Code »

    The BCM2835 AUX SPI has a shared interrupt line (with AUX UART).
    Downstream fixes this with an AUX irqchip to demux the IRQ sources and a
    DT change which breaks compatibility with older kernels. The AUX irqchip
    was already rejected for upstream[1] and the DT change would break
    working systems if the DTB is updated to a newer one. The latter issue
    was brought to my attention by Alex Graf.

    The root cause however is a bug in the shared handler. Shared handlers
    must check that interrupts are actually enabled before servicing the
    interrupt. Add a check that the TXEMPTY or IDLE interrupts are enabled.

    [1] https://patchwork.kernel.org/patch/9781221/

    Cc: Alexander Graf
    Cc: Marc Zyngier
    Cc: Mark Brown
    Cc: Eric Anholt
    Cc: Stefan Wahren
    Cc: Florian Fainelli
    Cc: Ray Jui
    Cc: Scott Branden
    Cc: bcm-kernel-feedback-list@broadcom.com
    Cc: linux-spi@vger.kernel.org
    Cc: linux-rpi-kernel@lists.infradead.org
    Cc: linux-arm-kernel@lists.infradead.org
    Signed-off-by: Rob Herring
    Reviewed-by: Eric Anholt
    Signed-off-by: Mark Brown

    Rob Herring
     

15 Feb, 2018

1 commit

  • d704afffe   spi: bcm2835aux: Avoid 64-bit arithmetic in xfer len calc ... Browse Code »

    We want to check for xfers that are over 30 microseconds. Rather than
    find how many µs a xfer will take, instead find how many bytes can be
    transferred in 30 µs. The latter must be less than 32 bits (since our
    clock speed is limited to 32 bits), while the former involves 64 bit
    quantities and more arithmetic operations.

    Signed-off-by: Trent Piepho
    Signed-off-by: Mark Brown

    Trent Piepho
     

11 Mar, 2016

1 commit

16 Feb, 2016

2 commits

  • e9dd4edcc   spi: bcm2835aux: fix CPOL/CPHA setting ... Browse Code »

    The auxiliary spi supports only CPHA=0 modes as the first bit is
    always output to the pin before the first clock cycle. In CPHA=1
    modes the first clock edge outputs the second bit hence the slave
    can never read the first bit.

    Also the CPHA registers switch between clocking data in/out on
    rising/falling edge hence depend on the CPOL setting.

    Signed-off-by: Stephan Olbrich
    Reviewed-by: Eric Anholt
    Signed-off-by: Mark Brown

    Stephan Olbrich
     
  • b4e2adef6   spi: bcm2835aux: set up spi-mode before asserting cs-gpio ... Browse Code »

    When using reverse polarity for clock (spi-cpol) on a device
    the clock line gets altered after chip-select has been asserted
    resulting in an additional clock beat, which confuses hardware.

    This happens due to the fact, the the hardware was initialized
    and reset at the begin and end of each transfer which results
    in default state for all lines except chip-select which is
    handled by the spi-subsystem as gpio-cs is used.

    To avoid this situation this patch moves the setup of polarity
    (spi-cpol and spi-cpha) outside of the chip-select into
    prepare_message, which is run prior to asserting chip-select.

    Signed-off-by: Stephan Olbrich
    Reviewed-by: Martin Sperl
    Tested-by: Martin Sperl
    Reviewed-by: Eric Anholt
    Signed-off-by: Mark Brown

    Stephan Olbrich
     

11 Feb, 2016

1 commit

10 Feb, 2016

1 commit

16 Oct, 2015

2 commits

  • 07bce09e1   spi: bcm2835aux: change initialization order and switch to platform_get_irq ... Browse Code »

    Change the initialization order of the HW so that the interrupt
    is only requested after the HW is initialized

    Also the use of irq_of_parse_and_map is replaced by platform_get_irq.

    Signed-off-by: Martin Sperl
    Signed-off-by: Mark Brown

    Martin Sperl
     
  • 72aac02b3   spi: bcm2835aux: fixed bad data on longer transfers ... Browse Code »

    There are strange issues with the auxiliary spi device that result
    in "lost" data in the RX path if the fifo is filled by too much
    (even though the status register is checked if new data can get filled
    in).

    This has been observed primarily for the interrupt case.
    Polling works fine, probably because the RX fifo is pulled immediately
    when in the tight polling loop.

    For that reason we have to limit the pending bytes to less than 15
    when filling the fifo in interrupt mode.

    There also was an issue returning the "wrong" last 1/2 bytes
    of a transfer when the transfer is not a multiple of 3 bytes.
    (this impacted polling and interrupt modes)

    Also fixed an overflow in the estimation of the transfer time used
    to decide if we run in interrupt or polling mode (found with the
    spi-bcm2835.c driver originally).

    Reported-by: Georgii Staroselskii
    Signed-off-by: Martin Sperl
    Signed-off-by: Mark Brown

    Martin Sperl
     

07 Oct, 2015

1 commit

  • 1ea29b39f   spi: bcm2835aux: add bcm2835 auxiliary spi device driver ... Browse Code »

    The bcm2835 has 2 auxiliary spi bus masters spi1 and spi2.

    This implements the driver to enable these devices.

    The driver does not implement native chip-selects but uses
    the aribtrary GPIO-chip-selects provided by the spi-chipselect.

    Note that this driver relies on the fact that
    the clock is implemented by the clk-bcm2835-aux driver,
    which enables/disables the HW block when requesting/releasing
    the clock.

    Signed-off-by: Martin Sperl
    Acked-by: Eric Anholt
    Signed-off-by: Mark Brown

    Martin Sperl