Commit Graph

257 Commits

Author SHA1 Message Date
Mark Brown
a057d737d6 Merge remote-tracking branches 'spi/fix/bcm63xx', 'spi/fix/doc', 'spi/fix/mediatek' and 'spi/fix/pl022' into spi-linus 2015-11-30 12:26:47 +00:00
Martin Sperl
77e8058810 spi: bugfix: spi_message.transfer_length does not get reset
When submitting an identical spi_message multiple times via spi_sync
the spi_message.frame_length does not get reset to 0 in __spi_validate
before adding up all spi_transfer.len resulting in
frame_length > actual_length on all but the first spi_sync call.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-11-27 12:55:22 +00:00
Thierry Reding
88c9321d1d spi: Add missing kerneldoc description for parameter
Commit ca5d248542 ("spi: Add THIS_MODULE to spi_driver in SPI core")
adds the new __spi_register_driver() function, but keeps the kerneldoc
for the spi_register_driver() function in place and forgets to add the
description for the new owner parameter.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-11-10 18:44:53 +00:00
Mark Brown
4c84518523 Merge remote-tracking branches 'spi/topic/omap-100k', 'spi/topic/omap-uwire', 'spi/topic/owner', 'spi/topic/pxa' and 'spi/topic/pxa2xx' into spi-next 2015-11-04 11:02:12 +00:00
Mark Brown
8c60348575 Merge remote-tracking branch 'spi/topic/doc' into spi-next 2015-11-04 11:02:03 +00:00
Mark Brown
3e7018def4 Merge remote-tracking branch 'spi/topic/core' into spi-next 2015-11-04 11:02:02 +00:00
Mark Brown
26cc44f8a3 Merge remote-tracking branch 'spi/fix/core' into spi-linus 2015-11-04 11:01:58 +00:00
Andrew F. Davis
ca5d248542 spi: Add THIS_MODULE to spi_driver in SPI core
Add spi_register_driver helper macro that adds THIS_MODULE to
spi_driver for the registering driver. We rename and modify
the existing spi_register_driver to enable this.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-28 10:30:12 +09:00
Franklin S Cooper Jr
abeedb0159 spi: Setup the master controller driver before setting the chipselect
SPI controllers may need to be properly setup before chip selects
can be used. Therefore, wait until the spi controller has a chance
to perform their setup procedure before trying to use the chip
select.

This also insures that the chip selects pins are in a good
state before asseting them which otherwise may cause confusion.

Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
Tested-by: Grygorii Strashko <grygorii.strashko@ti.com>
Tested-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-28 09:34:18 +09:00
Javier Martinez Canillas
97d56dc682 spi: fix kernel-doc warnings about missing return desc in spi.c
When building docs with make htmldocs, warnings about not having
a description for the return value are reported, i.e:

warning: No description found for return value of 'spi_register_driver'

Fix these by following the kernel-doc conventions explained in
Documentation/kernel-doc-nano-HOWTO.txt.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-24 01:28:35 +09:00
Mark Brown
0dc9631221 Merge branches 'topic/core' and 'topic/stats' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-doc 2015-10-24 01:28:29 +09:00
Andy Shevchenko
243f07be24 spi: core: use gpio_is_valid() helper
Check if GPIO pin is valid by API helper function.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-21 13:27:37 +01:00
Andy Shevchenko
5ab8d26212 spi: core: propagate return code of __spi_validate_bits_per_word()
Propagate the actual return code of __spi_validate_bits_per_word() in
spi_setup().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-16 16:05:33 +01:00
Jon Hunter
44af792731 spi: Map SPI OF client IRQ at probe time
Currently the IRQs for SPI client devices, registered via device-tree,
are mapped when the client devices are registered. If the corresponding
irq-chip has not been probed yet, then the probing of the client device
will fail and will not be retried. Resolve this by mapping the IRQ at
probe time and allow the probe to be deferred if the IRQ is not yet
available.

If of_irq_get() returns an error that is not -EPROBE_DEFER, then assume
that the SPI client does not have an IRQ and set the IRQ number to zero
(which is equivalent to irq_of_parse_and_map()).

This is based on some inputs from Thierry Reding <treding@nvidia.com>.

Cc: Thierry Reding <treding@nvidia.com>
Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-12 17:34:05 +01:00
Martin Sperl
6b7bc0618f spi: add transfer histogram statistics via sysfs
report transfer sizes as a histogram via the following files:
  /sys/class/spi_master/spi*/statistics/transfer_bytes_histo_*
  /sys/class/spi_master/spi*/spi*.*/statistics/transfer_bytes_histo_*

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-09-19 11:12:56 -07:00
Mark Brown
92243b6fc8 Linux 4.3-rc1
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Merge tag 'v4.3-rc1' into spi-fix-doc

Linux 4.3-rc1
2015-09-16 20:44:25 +01:00
Guenter Roeck
a394d63519 spi: Fix documentation of spi_alloc_master()
Actually, spi_master_put() after spi_alloc_master() must _not_ be followed
by kfree(). The memory is already freed with the call to spi_master_put()
through spi_master_class, which registers a release function. Calling both
spi_master_put() and kfree() results in often nasty (and delayed) crashes
elsewhere in the kernel, often in the networking stack.

This reverts commit eb4af0f534.

Link to patch and concerns: https://lkml.org/lkml/2012/9/3/269
or
http://lkml.iu.edu/hypermail/linux/kernel/1209.0/00790.html

Alexey Klimov: This revert becomes valid after
94c69f765f when spi-imx.c
has been fixed and there is no need to call kfree() so comment
for spi_alloc_master() should be fixed.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Alexey Klimov <alexey.klimov@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
2015-09-06 01:08:29 +01:00
Mark Brown
c92ec7c7ae Merge remote-tracking branches 'spi/topic/s3c64xx', 'spi/topic/sg', 'spi/topic/sh-msiof', 'spi/topic/spidev' and 'spi/topic/stats' into spi-next 2015-08-31 14:45:41 +01:00
Mark Brown
8e42ac814c Merge remote-tracking branch 'spi/topic/dma' into spi-next 2015-08-31 14:45:28 +01:00
Stefan Brüns
63ab645f4d spi: check bits_per_word in spi_setup
This allows drivers for devices connected via SPI to check if the
controller supports a given bits_per_word value during setup.
Currently any BPW value is accepted durings setup, and transfers
are rejected later.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-08-26 18:58:29 +01:00
Mark Brown
7dc9fbc342 spi: Fall back to master maximum speed if no slave speed specified
If a slave appears with no maximum transfer speed specified fall back to
using the maximum for the master instead.  It's questionable if we
should let slaves do this but let's be defensive.

Signed-off-by: Mark Brown <broonie@kernel.org>
2015-08-21 10:24:04 -07:00
Leilk Liu
c37f45b5f1 spi: support spi without dma channel to use can_dma()
For spi without dma channel and use can_dma(), it can
use master->dev for struct device.

Signed-off-by: Leilk Liu <leilk.liu@mediatek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-07-24 18:35:00 +01:00
Martin Sperl
eca2ebc7e0 spi: expose spi_master and spi_device statistics via sysfs
per spi-master statistics accessible as:
  /sys/class/spi_master/spi*/statistics/*

per spi-device statistics accessible via:
  /sys/class/spi_master/spi*/spi*.*/statistics/*

The following statistics are exposed as separate "files" inside
these directories:
* messages              number of spi_messages
* transfers             number of spi_transfers
* bytes                 number of bytes transferred
* bytes_rx              number of bytes transmitted
* bytes_tx              number of bytes received
* errors                number of errors encounterd
* timedout              number of messages that have timed out
* spi_async             number of spi_messages submitted using spi_async
* spi_sync              number of spi_messages submitted using spi_sync
* spi_sync_immediate    number of spi_messages submitted using spi_sync,
                        that are handled immediately without a context switch
                        to the spi_pump worker-thread

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-07-07 13:33:23 +01:00
Andrew Gabbasov
65598c13fd spi: Fix per-page mapping of unaligned vmalloc-ed buffer
spi_map_buf() processes mapping of vmalloc-ed buffers in a special way,
making mapping of every page separately. However, if the buffer is not
aligned to page boundary (e.g. sub-array in a vmalloc-ed array), it
fills the scatter table with page-size unaligned pieces, that cross
page boundaries. This is incorrect and can, for example, cause memory
corruption and various crashes when working with ubifs on spi-nor chips
(though those drivers are themselves buggy in that they should be
providing DMAable memory to the SPI framework).

Fix this by using proper scatter table size and intra-page buffer lengths,
so that the whole buffer splits into separate scatter table entries on
page boundaries.

Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-07-07 13:09:46 +01:00
Martin Sperl
4b786458ed spi: restore rx/tx_buf in case of unset CONFIG_HAS_DMA
The case where spi_master sets the flags SPI_MASTER_MUST_RX/TX while
CONFIG_HAS_DMA is unset (which is unlikley) together with a driver
that reuses spi_messages with rx/tx_buff set to NULL, can result in:
* data disclosure over the SPI (for tx_buf == NULL)
* memory corruption (for rx_buf == NULL)

This happenes when dummy_rx/dummy_tx are changing address due to krealloc
or free and an allocation of the memory by a different part of the kernel.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-06-02 21:54:56 +01:00
Martin Sperl
8e76ef88f6 spi: fix race freeing dummy_tx/rx before it is unmapped
Fix a race (with some kernel configurations) where a queued
master->pump_messages runs and frees dummy_tx/rx before
spi_unmap_msg is running (or is finished).

This results in the following messages:
  BUG: Bad page state in process
  page:db7ba030 count:0 mapcount:0 mapping:  (null) index:0x0
  flags: 0x200(arch_1)
  page dumped because: PAGE_FLAGS_CHECK_AT_PREP flag set
  ...

Reported-by: Noralf Trønnes <noralf@tronnes.org>
Suggested-by: Noralf Trønnes <noralf@tronnes.org>
Tested-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
2015-05-11 19:05:27 +01:00
Robin Gong
f8bb820da4 spi: check tx_buf and rx_buf in spi_unmap_msg
Some spi device drivers use the same tx_buf and rx_buf repeatly for better
performance such as driver/input/touchsreen/ads7846.c, but spi core grab tx_buf
/rx_buf of transfer and set them as dummy_tx/dummy_rx once they are NULL. Thus,
in the second time the tx_buf/rx_buf will be replaced by dummy_tx/dummy_rx and
the data which produced by the last tx or rx may be wrongly sent to the device
or handled by the upper level protocol. This patch just keep the orignal value
of tx_buf/rx_buf if they are NULL after this transfer processed.

Signed-off-by: Robin Gong <b38343@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-04-16 18:58:05 +01:00
Mark Brown
8afba181b9 Merge remote-tracking branches 'spi/topic/omap-100k', 'spi/topic/omap-uwire', 'spi/topic/pl022', 'spi/topic/pm' and 'spi/topic/pxa2xx' into spi-next 2015-04-11 23:09:18 +01:00
Mark Brown
431959c079 Merge remote-tracking branches 'spi/topic/blackfin', 'spi/topic/cadence', 'spi/topic/dw' and 'spi/topic/err' into spi-next 2015-04-11 23:09:09 +01:00
Mark Brown
f9de73426c Merge remote-tracking branches 'spi/topic/atmel', 'spi/topic/bcm2385', 'spi/topic/bcm2835', 'spi/topic/bcm53xx' and 'spi/topic/bitbang' into spi-next 2015-04-11 23:09:03 +01:00
Mark Brown
e897f795a9 Merge remote-tracking branch 'spi/topic/core' into spi-next 2015-04-11 23:09:00 +01:00
Geert Uytterhoeven
ff61eb4220 spi: Make master->handle_err() callback optional to avoid crashes
If a driver doesn't implement the master->handle_err() callback and an
SPI transfer fails, the kernel will crash with a NULL pointer
dereference:

    Unable to handle kernel NULL pointer dereference at virtual address 00000000
    pgd = c0003000
    [00000000] *pgd=80000040004003, *pmd=00000000
    Internal error: Oops: 80000206 [#1] SMP ARM
    Modules linked in:
    CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.0.0-rc7-koelsch-05861-g1fc9fdd4add4f783 #1046
    Hardware name: Generic R8A7791 (Flattened Device Tree)
    task: eec359c0 ti: eec54000 task.ti: eec54000
    PC is at 0x0
    LR is at spi_transfer_one_message+0x1cc/0x1f0

Make the master->handle_err() callback optional to avoid the crash.

Also fix a spelling mistake in the callback documentation while we're at
it.

Fixes: b716c4ffc6 ("spi: introduce master->handle_err() callback")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-04-07 19:41:32 +01:00
Dmitry Torokhov
22de3ef94b spi: of: do explicitly request modules for of-registered devices
Trying to register an SPI device asynchronously (via async_schedule() call)
results in an ugly complaint from request_module() warning about potential
deadlock (because request_module tries to wait for async works to
complete, the caller is also an async work in this case).

While we could try to switch to using request_module_nowait(), other buses,
as well as SPI itself when not using device tree, do not try to load
modules explicitly, but rather rely on the standard infrastructure (such as
udev) to execute module loading. There is no reason why SPI OF-described
devices should be treated differently.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-03-25 14:34:52 -07:00
Uwe Kleine-König
391949b6f0 spi: trigger trace event for message-done before mesg->complete
With spidev the mesg->complete callback points to spidev_complete.
Calling this unblocks spidev_sync and so spidev_sync_write finishes. As
the struct spi_message just read is a local variable in
spidev_sync_write and recording the trace event accesses this message
the recording is better done first. The same can happen for
spidev_sync_read.

This fixes an oops observed on a 3.14-rt system with spidev activity
after

	echo 1 > /sys/kernel/debug/tracing/events/spi/enable

.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
2015-03-18 11:34:10 +00:00
Ivan T. Ivanov
1a7b7ee72c spi: Ensure that CS line is in non-active state after spi_setup()
Some devices samples state of the chip select signal during power up
and act differently based on this state, so SPI core should ensure
that CS line is driven in non-active state after spi_setup().

Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-03-16 14:06:48 +00:00
Lars-Peter Clausen
ea022bbb00 spi: Remove support for legacy PM
All SPI drivers have been converted from legacy suspend/resume callbacks to
dev_pm_ops. So we can finally remove support for legacy PM from the SPI
core.

Since there aren't any special bus specific things to do during
suspend/resume and since the PM core will automatically fallback directly to
using the device's PM ops if no bus PM ops are specified there is no need to
have any special SPI bus PM ops.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-03-08 19:57:55 +00:00
Andy Shevchenko
b716c4ffc6 spi: introduce master->handle_err() callback
This callback would be useful to handle an error that occurs in the generic
implementation of transfer_one_message(). The good candidate for this is to
drain FIFO and / or to terminate DMA transfers when timeout happened.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-03-06 19:41:56 +00:00
Mark Brown
8328509c4b Merge remote-tracking branches 'spi/topic/img-spfi', 'spi/topic/imx', 'spi/topic/inline', 'spi/topic/meson' and 'spi/topic/mxs' into spi-next 2015-02-08 11:16:52 +08:00
Mark Brown
d6cd09bea9 Merge remote-tracking branches 'spi/topic/falcon', 'spi/topic/fsf', 'spi/topic/fsl', 'spi/topic/fsl-dspi' and 'spi/topic/gpio' into spi-next 2015-02-08 11:16:46 +08:00
Nicholas Mc Guire
682a71b284 spi: match var type to return type of wait_for_completion
return type of wait_for_completion_timeout is unsigned long not int, this
patch changes the type of m from int to unsigned long.

Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-02-04 20:52:32 +00:00
Jarkko Nikula
2c658e212c spi: Remove FSF mailing addresses
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2014-12-22 15:32:42 +00:00
Linus Torvalds
7ef58b32f5 Devicetree changes for v3.19
Lots of activity in the devicetree code for v3.18. Most of it is related
 to getting all of the overlay support code in place, but there are other
 important things in there.
 
 There are a few trivial merge conflicts. They shouldn't give you any
 trouble.
 
 Highlights:
 - OF_RECONFIG notifiers for SPI, I2C and Platform devices. Those
   subsystems can now respond to live changes to the device tree.
 - CONFIG_OF_OVERLAY method for applying live changes to the device tree
 - Removal of the of_allnodes list. This used to be used to iterate over
   all the nodes in the device tree, but it is unnecessary because the
   same thing can be done by iterating over the list of child pointers.
   Getting rid of of_allnodes saves some memory and avoids the
   possibility of of_allnodes being sorted differently from the child
   lists.
 - Support for retrieving original DTB blob via sysfs. Needed by kexec.
 - More unittests
 - Documentation and minor bug fixes
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Merge tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux

Pull devicetree changes from Grant Likely:
 "Lots of activity in the devicetree code for v3.18.  Most of it is
  related to getting all of the overlay support code in place, but there
  are other important things in there.

  Highlights:

   - OF_RECONFIG notifiers for SPI, I2C and Platform devices.  Those
     subsystems can now respond to live changes to the device tree.

   - CONFIG_OF_OVERLAY method for applying live changes to the device
     tree

   - Removal of the of_allnodes list.  This used to be used to iterate
     over all the nodes in the device tree, but it is unnecessary
     because the same thing can be done by iterating over the list of
     child pointers.  Getting rid of of_allnodes saves some memory and
     avoids the possibility of of_allnodes being sorted differently from
     the child lists.

   - Support for retrieving original DTB blob via sysfs.  Needed by
     kexec.

   - More unittests

   - Documentation and minor bug fixes"

* tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux: (42 commits)
  of: Delete unnecessary check before calling "of_node_put()"
  of: Drop ->next pointer from struct device_node
  spi: Check for spi_of_notifier when CONFIG_OF_DYNAMIC=y
  of: support passing console options with stdout-path
  of: add optional options parameter to of_find_node_by_path()
  of: Add bindings for chosen node, stdout-path
  of: Remove unneeded and incorrect MODULE_DEVICE_TABLE
  ARM: dt: fix up PL011 device tree bindings
  of: base, fix of_property_read_string_helper kernel-doc
  of: remove select of non-existant OF_DEVICE config symbol
  spi/of: Add OF notifier handler
  spi/of: Create new device registration method and accessors
  i2c/of: Add OF_RECONFIG notifier handler
  i2c/of: Factor out Devicetree registration code
  of/overlay: Add overlay unittests
  of/overlay: Introduce DT overlay support
  of/reconfig: Add OF_DYNAMIC notifier for platform_bus_type
  of/reconfig: Always use the same structure for notifiers
  of/reconfig: Add debug output for OF_RECONFIG notifiers
  of/reconfig: Add empty stubs for the of_reconfig methods
  ...
2014-12-11 13:06:58 -08:00
Mark Brown
fc9e0f71f2 spi: Only idle the message pump in the worker kthread
In order to avoid the situation where the kthread is waiting for another
context to make the hardware idle let the message pump know if it's being
called from the worker thread context and if it isn't then defer to the
worker thread instead of idling the hardware immediately. This will ensure
that if this situation happens we block rather than busy waiting.

Signed-off-by: Mark Brown <broonie@kernel.org>
2014-12-11 12:25:30 +00:00
Mark Brown
0461a41498 spi: Pump transfers inside calling context for spi_sync()
If we are using the standard SPI message pump (which all drivers should be
transitioning over to) then special case the message enqueue and instead of
starting the worker thread to push messages to the hardware do so in the
context of the caller if the controller is idle. This avoids a context
switch in the common case where the controller has a single user in a
single thread, for short PIO transfers there may be no need to context
switch away from the calling context to complete the transfer.

The code is a bit more complex than is desirable in part due to the need
to handle drivers not using the standard queue and in part due to handling
the various combinations of bus locking and asynchronous submission in
interrupt context.

It is still suboptimal since it will still wake the message pump for each
transfer in order to schedule idling of the hardware and if multiple
contexts are using the controller simultaneously a caller may end up
pumping a message for some random other thread rather than for itself,
and if the thread ends up deferring due to another context idling the
hardware then it will just busy wait.  It can, however, have the benefit
of aggregating power up and down of the hardware when a caller performs
a series of transfers back to back without any need for the use of
spi_async().

Signed-off-by: Mark Brown <broonie@kernel.org>
2014-12-11 12:23:51 +00:00
Mark Brown
983aee5d70 spi: Check to see if the device is processing a message before we idle
cur_msg is updated under the queue lock and holds the message we are
currently processing. Since currently we only ever do removals in the
pump kthread it doesn't matter in what order we do things but we want
to be able to push things out from the submitting thread so pull the
check to see if we're currently handling a message before we check to
see if the queue is idle.

Signed-off-by: Mark Brown <broonie@kernel.org>
2014-12-11 12:23:23 +00:00
Mark Brown
5424d43e4d spi: Move queue data structure initialisation to main master init
Since most devices now do use the standard queue and in order to avoid
initialisation ordering issues being introduced by further refactorings
to improve performance move the initialisation of the queue and the lock
for it to the main master allocation.

Signed-off-by: Mark Brown <broonie@kernel.org>
2014-12-11 12:23:13 +00:00
Mark Brown
19a0368028 Merge remote-tracking branch 'spi/topic/core' into spi-next 2014-12-08 12:17:11 +00:00
Jarkko Nikula
98a8f5a053 spi: core: Do not mangle error code from kthread_run()
kthread_run() could return ERR_PTR(-EINTR) from kthread_create_on_node().
Return the actual error code in spi_init_queue() instead of mangling it to
-ENOMEM.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2014-12-04 22:42:37 +00:00
Fabio Estevam
5267720e75 spi: Check for spi_of_notifier when CONFIG_OF_DYNAMIC=y
Since commit ce79d54ae4 ("spi/of: Add OF notifier handler") the
following warning is seen on a imx53 system that has CONFIG_OF_DYNAMIC=n:

[    0.048119] ------------[ cut here ]------------
[    0.048146] WARNING: CPU: 0 PID: 1 at drivers/spi/spi.c:2419 spi_init+0x60/0xa8()
[    0.048158] Modules linked in:
[    0.048183] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.18.0-rc6-next-20141126-00003-g9388e85 #2080
[    0.048193] Hardware name: Freescale i.MX53 (Device Tree Support)
[    0.048203] Backtrace:
[    0.048235] [<80011f74>] (dump_backtrace) from [<80012110>] (show_stack+0x18/0x1c)
[    0.048246]  r6:00000973 r5:00000000 r4:00000000 r3:00000000
[    0.048284] [<800120f8>] (show_stack) from [<806b3ad8>] (dump_stack+0x88/0xa4)
[    0.048312] [<806b3a50>] (dump_stack) from [<8002a55c>] (warn_slowpath_common+0x80/0xbc)
[    0.048320]  r5:8096cfcc r4:00000000
[    0.048343] [<8002a4dc>] (warn_slowpath_common) from [<8002a5bc>] (warn_slowpath_null+0x24/0x2c)
[    0.048354]  r8:8096cf6c r7:809355ec r6:ddcd7c00 r5:812029e4 r4:00000000
[    0.048389] [<8002a598>] (warn_slowpath_null) from [<8096cfcc>] (spi_init+0x60/0xa8)
[    0.048405] [<8096cf6c>] (spi_init) from [<80008a7c>] (do_one_initcall+0x88/0x1e0)
[    0.048415]  r5:8099e018 r4:8099e018
[    0.048438] [<800089f4>] (do_one_initcall) from [<80935e38>] (kernel_init_freeable+0x110/0x1e0)
[    0.048448]  r10:80980700 r9:809806e4 r8:000000cc r7:809355ec r6:809f8940 r5:00000002
[    0.048478]  r4:8098d744
[    0.048508] [<80935d28>] (kernel_init_freeable) from [<806ae574>] (kernel_init+0x10/0xf4)
[    0.048517]  r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:806ae564
[    0.048547]  r4:00000000
[    0.048565] [<806ae564>] (kernel_init) from [<8000ed68>] (ret_from_fork+0x14/0x2c)
[    0.048574]  r4:00000000 r3:00000000
[    0.048616] ---[ end trace 405a65d177dae4fd ]---

Only check of_reconfig_notifier_register() in the CONFIG_OF_DYNAMIC=y case,
as intended by commit ce79d54ae4.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
2014-12-03 23:12:39 +00:00
Pantelis Antoniou
ce79d54ae4 spi/of: Add OF notifier handler
Add OF notifier handler needed for creating/destroying spi devices
according to dynamic runtime changes in the DT live tree. This code is
enabled when CONFIG_OF_DYNAMIC is selected.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Cc: <linux-spi@vger.kernel.org>
2014-11-25 15:36:24 +00:00