* refs/heads/tmp-7ba5557
Linux 4.4.139
Bluetooth: Fix connection if directed advertising and privacy is used
cdc_ncm: avoid padding beyond end of skb
dm thin: handle running out of data space vs concurrent discard
block: Fix transfer when chunk sectors exceeds max
spi: Fix scatterlist elements size in spi_map_buf
Btrfs: fix unexpected cow in run_delalloc_nocow
ALSA: hda/realtek - Add a quirk for FSC ESPRIMO U9210
Input: elantech - fix V4 report decoding for module with middle key
Input: elantech - enable middle button of touchpads on ThinkPad P52
Input: elan_i2c_smbus - fix more potential stack buffer overflows
udf: Detect incorrect directory size
xen: Remove unnecessary BUG_ON from __unbind_from_irq()
Input: elan_i2c - add ELAN0618 (Lenovo v330 15IKB) ACPI ID
video: uvesafb: Fix integer overflow in allocation
NFSv4: Fix possible 1-byte stack overflow in nfs_idmap_read_and_verify_message
nfsd: restrict rd_maxcount to svc_max_payload in nfsd_encode_readdir
media: dvb_frontend: fix locking issues at dvb_frontend_get_event()
media: cx231xx: Add support for AverMedia DVD EZMaker 7
media: v4l2-compat-ioctl32: prevent go past max size
perf intel-pt: Fix packet decoding of CYC packets
perf intel-pt: Fix "Unexpected indirect branch" error
perf intel-pt: Fix MTC timing after overflow
perf intel-pt: Fix decoding to accept CBR between FUP and corresponding TIP
perf intel-pt: Fix sync_switch INTEL_PT_SS_NOT_TRACING
perf tools: Fix symbol and object code resolution for vdso32 and vdsox32
mfd: intel-lpss: Program REMAP register in PIO mode
backlight: tps65217_bl: Fix Device Tree node lookup
backlight: max8925_bl: Fix Device Tree node lookup
backlight: as3711_bl: Fix Device Tree node lookup
xfrm: skip policies marked as dead while rehashing
xfrm: Ignore socket policies when rebuilding hash tables
UBIFS: Fix potential integer overflow in allocation
ubi: fastmap: Cancel work upon detach
md: fix two problems with setting the "re-add" device state.
linvdimm, pmem: Preserve read-only setting for pmem devices
scsi: zfcp: fix missing REC trigger trace on enqueue without ERP thread
scsi: zfcp: fix missing REC trigger trace for all objects in ERP_FAILED
scsi: zfcp: fix missing REC trigger trace on terminate_rport_io for ERP_FAILED
scsi: zfcp: fix missing REC trigger trace on terminate_rport_io early return
scsi: zfcp: fix misleading REC trigger trace where erp_action setup failed
scsi: zfcp: fix missing SCSI trace for retry of abort / scsi_eh TMF
scsi: zfcp: fix missing SCSI trace for result of eh_host_reset_handler
scsi: qla2xxx: Fix setting lower transfer speed if GPSC fails
iio:buffer: make length types match kfifo types
Btrfs: fix clone vs chattr NODATASUM race
time: Make sure jiffies_to_msecs() preserves non-zero time periods
MIPS: io: Add barrier after register read in inX()
PCI: pciehp: Clear Presence Detect and Data Link Layer Status Changed on resume
MIPS: BCM47XX: Enable 74K Core ExternalSync for PCIe erratum
mtd: cfi_cmdset_0002: Avoid walking all chips when unlocking.
mtd: cfi_cmdset_0002: Fix unlocking requests crossing a chip boudary
mtd: cfi_cmdset_0002: fix SEGV unlocking multiple chips
mtd: cfi_cmdset_0002: Use right chip in do_ppb_xxlock()
mtd: cfi_cmdset_0002: Change write buffer to check correct value
RDMA/mlx4: Discard unknown SQP work requests
IB/qib: Fix DMA api warning with debug kernel
of: unittest: for strings, account for trailing \0 in property length field
ARM: 8764/1: kgdb: fix NUMREGBYTES so that gdb_regs[] is the correct size
powerpc/fadump: Unregister fadump on kexec down path.
cpuidle: powernv: Fix promotion from snooze if next state disabled
powerpc/ptrace: Fix enforcement of DAWR constraints
powerpc/ptrace: Fix setting 512B aligned breakpoints with PTRACE_SET_DEBUGREG
powerpc/mm/hash: Add missing isync prior to kernel stack SLB switch
fuse: fix control dir setup and teardown
fuse: don't keep dead fuse_conn at fuse_fill_super().
fuse: atomic_o_trunc should truncate pagecache
Bluetooth: hci_qca: Avoid missing rampatch failure with userspace fw loader
ipmi:bt: Set the timeout before doing a capabilities check
branch-check: fix long->int truncation when profiling branches
mips: ftrace: fix static function graph tracing
lib/vsprintf: Remove atomic-unsafe support for %pCr
ASoC: cirrus: i2s: Fix {TX|RX}LinCtrlData setup
ASoC: cirrus: i2s: Fix LRCLK configuration
ASoC: dapm: delete dapm_kcontrol_data paths list before freeing it
1wire: family module autoload fails because of upper/lower case mismatch.
usb: do not reset if a low-speed or full-speed device timed out
signal/xtensa: Consistenly use SIGBUS in do_unaligned_user
serial: sh-sci: Use spin_{try}lock_irqsave instead of open coding version
m68k/mm: Adjust VM area to be unmapped by gap size for __iounmap()
x86/spectre_v1: Disable compiler optimizations over array_index_mask_nospec()
fs/binfmt_misc.c: do not allow offset overflow
w1: mxc_w1: Enable clock before calling clk_get_rate() on it
libata: Drop SanDisk SD7UB3Q*G1001 NOLPM quirk
libata: zpodd: small read overflow in eject_tray()
libata: zpodd: make arrays cdb static, reduces object code size
cpufreq: Fix new policy initialization during limits updates via sysfs
ALSA: hda: add dock and led support for HP ProBook 640 G4
ALSA: hda: add dock and led support for HP EliteBook 830 G5
ALSA: hda - Handle kzalloc() failure in snd_hda_attach_pcm_stream()
btrfs: scrub: Don't use inode pages for device replace
driver core: Don't ignore class_dir_create_and_add() failure.
ext4: fix fencepost error in check for inode count overflow during resize
ext4: update mtime in ext4_punch_hole even if no blocks are released
tcp: verify the checksum of the first data segment in a new connection
bonding: re-evaluate force_primary when the primary slave name changes
usb: musb: fix remote wakeup racing with suspend
Btrfs: make raid6 rebuild retry more
tcp: do not overshoot window_clamp in tcp_rcv_space_adjust()
Revert "Btrfs: fix scrub to repair raid6 corruption"
net/sonic: Use dma_mapping_error()
net: qmi_wwan: Add Netgear Aircard 779S
atm: zatm: fix memcmp casting
ipvs: fix buffer overflow with sync daemon and service
netfilter: ebtables: handle string from userspace with care
xfrm6: avoid potential infinite loop in _decode_session6()
ANDROID: Add kconfig to make dm-verity check_at_most_once default enabled
ANDROID: sdcardfs: fix potential crash when reserved_mb is not zero
Change-Id: Ibcd2b6614843e4e8fd5a57acf350a9e83e1c0dbc
Signed-off-by: Blagovest Kolenichev <bkolenichev@codeaurora.org>
commit ce99319a182fe766be67f96338386f3ec73e321c upstream.
When SPI transfers can be offloaded using DMA, the SPI core need to
build a scatterlist to make sure that the buffer to be transferred is
dma-able.
This patch fixes the scatterlist entry size computation in the case
where the maximum acceptable scatterlist entry supported by the DMA
controller is less than PAGE_SIZE, when the buffer is vmalloced.
For each entry, the actual size is given by the minimum between the
desc_len (which is the max buffer size supported by the DMA controller)
and the remaining buffer length until we cross a page boundary.
Fixes: 65598c13fd ("spi: Fix per-page mapping of unaligned vmalloc-ed buffer")
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for registering SPI slave controllers using the existing SPI
master framework:
- SPI slave controllers must use spi_alloc_slave() instead of
spi_alloc_master(), and should provide an additional callback
"slave_abort" to abort an ongoing SPI transfer request,
- SPI slave controllers are added to a new "spi_slave" device class,
- SPI slave handlers can be bound to the SPI slave device represented
by an SPI slave controller using a DT child node named "slave",
- Alternatively, (un)binding an SPI slave handler to the SPI slave
device represented by an SPI slave controller can be done by
(un)registering the slave device through a sysfs virtual file named
"slave".
From the point of view of an SPI slave protocol handler, an SPI slave
controller looks almost like an ordinary SPI master controller. The only
exception is that a transfer request will block on the remote SPI
master, and may be cancelled using spi_slave_abort().
Change-Id: I251c5b7247ee7088285e42dd3b3cdce9c56cb9f7
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Git-commit: 6c364062bfed3c34490e85bea52ff6e2d4f0f281
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Alok Chauhan <alokc@codeaurora.org>
Extract the parsing of SPI slave-specific properties into its own
function, so it can be reused later for SPI slave controllers.
Change-Id: I6e401d369c7ee7aead1f404c8e0b6dfffcb5b65d
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Git-commit: c2e51ac3d0542440d5b2b8b52ff2ad00751af4da
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Alok Chauhan <alokc@codeaurora.org>
Fix parent-device reference leak due to SPI-core taking an unnecessary
reference to the parent when allocating the master structure, a
reference that was never released.
Note that driver core takes its own reference to the parent when the
master device is registered.
Fixes: 49dce689ad ("spi doesn't need class_device")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
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>
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>
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>
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>
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>
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>
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>
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>
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>
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
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>
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>
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>
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>
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>
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>
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
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>
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>
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>
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
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>
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>
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>
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>
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
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQIcBAABAgAGBQJUiaTJAAoJEMWQL496c2LNdKkP/1rk20JXzJc948Z3VFZPXkzf
TUKXC+Qn0FmVjQhESkx6LxLDrMDTQlQLlWBmFuWRB87Fk5E32FEf5zzW7I9oQPS4
msIqJoYf5T7EPlmJ/85156xjK5ezc0OyoKEizn23mcKrJE4bmXQEbVw99UUFhq4R
Oz1a1ZPQQSSaMteKftOoRBiE3bJut3tJ3dfufNjwOuXi5rALJ0DVxuOeU/Hba13d
t05qlImwocKXGBDd/B4psBI5fZl4Tf4AmGOD9aU7YHxrLg4jOCbvqies3DQQ0q3D
o9YZBnuBw7A3tzJJ3F5KajRnFLazJBOV5BKGo7eYuTzT56mpZW/HF6eS9b1DbP9x
4q71Vd5qhIuU9JsQAStfZ6pdx3FBXRNGpIXXfwzbCSdaePIuOKS17zvA/Iy5bWeA
2TyqgMuKZwnXOXxQesMZJYIw2IEnIyobzh0A1wAnvReyos/nHF/tha/SA/Jutq1s
+0gOkMlPW2EdpADmlfLPRSHgSqO8bfCPeNPihn672MS2dAv9H+XRLcoKuSNErhdl
1gYtnR7IK+Sl0KmMC5YoMvXPchkV5YS2qEp1f3p+ZmgcMSWyHHKMtf8VwjNTaSBU
e1AshH6HvmYEPt0cnntSMAxbw+N596QjkVp4RbHsLpyj7qeUVVY56/K/aiM7M69P
BvJkuewrhsAxyM2X2OsD
=ak0A
-----END PGP SIGNATURE-----
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
...
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>
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>
