Earlier commit:
"spi: Pick spi bus number from Linux idr or spi alias"
(SHA1:9b61e302210eba55768962f2f11e96bb508c2408)
has introduced some checkpatch issues. As pointed by
Lukas Wunner this patch does the following:
- remove whitespaces
- fix warnings, suspect code indent for conditional statements
- fix errors, code indent should use tabs
- remove spaces at the start of the line
Signed-off-by: Suniel Mahesh <sunil.m@techveda.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Modify existing code, for automatically picking the spi bus number based
on Linux idr scheme as mentioned in FIXME.
This patch does the following:
(a) Remove the now unnecessary code which was allocating bus numbers using
ATOMIC_INIT and atomic_dec_return macros.
(b) If we have an alias, pick the bus number from alias ID
(c) Convert to linux idr interface
Signed-off-by: Suniel Mahesh <sunil.m@techveda.org>
Signed-off-by: Karthik Tummala <karthik@techveda.org>
Tested-by: Karthik Tummala <karthik@techveda.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Use a bit more compact of_property_read_bool() calls instead of the
of_find_property() calls -- symmetrically with the of_property_read_u32()
calls already done in of_spi_parse_dt().
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
MacBooks and MacBook Pros introduced since 2015 return empty _CRS data
for SPI slaves, causing device initialization to fail. Most of the
information that would normally be conveyed via _CRS is available
through ACPI device properties instead, so take advantage of them.
The meaning and appropriate usage of the device properties was reverse
engineered by Ronald Tschalär and carried over from these commits
authored by him:
https://github.com/cb22/macbook12-spi-driver/commit/9a416d699ef4https://github.com/cb22/macbook12-spi-driver/commit/0c34936ed9a1
According to Ronald, the device properties have the following meaning:
spiSclkPeriod /* period in ns */
spiWordSize /* in number of bits */
spiBitOrder /* 1 = MSB_FIRST, 0 = LSB_FIRST */
spiSPO /* clock polarity: 0 = low, 1 = high */
spiSPH /* clock phase: 0 = first, 1 = second */
spiCSDelay /* delay between cs and receive on reads in 10 us */
resetA2RUsec /* active-to-receive delay? */
resetRecUsec /* receive delay? */
Reported-by: Leif Liddy <leif.liddy@gmail.com>
Tested-by: Ronald Tschalär <ronald@innovation.ch>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
add_uevent_var() can fail, let caller know about this.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Now struct spi_master is used for both SPI master and slave controllers,
it makes sense to rename it to struct spi_controller, and replace
"master" by "controller" where appropriate.
For now this conversion is done for SPI core infrastructure only.
Wrappers are provided for backwards compatibility, until all SPI drivers
have been converted.
Noteworthy details:
- SPI_MASTER_GPIO_SS is retained, as it only makes sense for SPI
master controllers,
- spi_busnum_to_master() is retained, as it looks up masters only,
- A new field spi_device.controller is added, but spi_device.master is
retained for compatibility (both are always initialized by
spi_alloc_device()),
- spi_flash_read() is used by SPI masters only.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.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().
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Octal permissions are preferred over symbolic permissions.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add an interface analogous to ->can_dma() for spi_flash_read()
interface. This will enable SPI controller drivers to inform SPI core
when not to do DMA mappings.
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The generic SPI code calculates how long the issued transfer would take
and adds 100ms in addition to the timeout as tolerance. On my 500 MHz
Lantiq Mips SoC I am getting timeouts from the SPI like this when the
system boots up:
m25p80 spi32766.4: SPI transfer timed out
blk_update_request: I/O error, dev mtdblock3, sector 2
SQUASHFS error: squashfs_read_data failed to read block 0x6e
After increasing the tolerance for the timeout to 200ms I haven't seen
these SPI transfer time outs any more.
The Lantiq SPI driver in use here has an extra work queue in between,
which gets triggered when the controller send the last word and the
hardware FIFOs used for reading and writing are only 8 words long.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Many boards form list of spi_board_info entries depending on config,
and it is possible to end up with empty list. Do not report error
in such cases.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Generic device properties support statically defined property sets. For
them to be usable, we need to attach these property sets before devices
are registered and probed. Allowing to attach property list to
spi_board_info structure will allow non-ACPI non-DT boards switch to using
generic properties and get rid of custom platform data.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
We are going to move scheduler ABI details to <uapi/linux/sched/types.h>,
which will be used from a number of .c files.
Create empty placeholder header that maps to <linux/types.h>.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- Update of the ACPICA code in the kernel to upstream revision
20170119 including:
* Fixes related to the handling of the bit width and bit offset
fields in Generic Address Structure (Lv Zheng).
* ACPI resources handling fix related to invalid resource
descriptors (Bob Moore).
* Fix to enable implicit result conversion for several ASL
library functions (Bob Moore).
* Support for method invocations as target operands in AML
(Bob Moore).
* Fix to use a correct operand type for DeRefOf() in some
situations (Bob Moore).
* Utilities updates (Bob Moore, Lv Zheng).
* Disassembler/debugger updates (David Box, Lv Zheng).
* Build fixes (Colin Ian King, Lv Zheng).
* Update of copyright notices in all files (Bob Moore).
- Fix for modalias handling for SPI and I2C devices with
DT-compatible identification strings (Dan O'Donovan).
- Fixes for the ACPI EC and button drivers (Lv Zheng).
- ACPI processor handling fix related to CPU hotplug (online/offline)
on x86 (Vitaly Kuznetsov).
- Suspend quirk to save/restore NVS memory over S3 transitions for
Lenovo G50-45 (Zhang Rui).
- Message formatting fix for the ACPI APEI code (Colin Ian King).
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Merge tag 'acpi-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI updates from Rafael Wysocki:
"These update the ACPICA code in the kernel to upstream revision
20170119, which among other things updates copyright notices in all of
the ACPICA files, fix a couple of issues in the ACPI EC and button
drivers, fix modalias handling for non-discoverable devices with
DT-compatible identification strings, add a suspend quirk for one
platform and fix a message in the APEI code.
Specifics:
- Update of the ACPICA code in the kernel to upstream revision
20170119 including:
+ Fixes related to the handling of the bit width and bit offset
fields in Generic Address Structure (Lv Zheng)
+ ACPI resources handling fix related to invalid resource
descriptors (Bob Moore)
+ Fix to enable implicit result conversion for several ASL library
functions (Bob Moore)
+ Support for method invocations as target operands in AML (Bob
Moore)
+ Fix to use a correct operand type for DeRefOf() in some
situations (Bob Moore)
+ Utilities updates (Bob Moore, Lv Zheng)
+ Disassembler/debugger updates (David Box, Lv Zheng)
+ Build fixes (Colin Ian King, Lv Zheng)
+ Update of copyright notices in all files (Bob Moore)
- Fix for modalias handling for SPI and I2C devices with
DT-compatible identification strings (Dan O'Donovan)
- Fixes for the ACPI EC and button drivers (Lv Zheng)
- ACPI processor handling fix related to CPU hotplug (online/offline)
on x86 (Vitaly Kuznetsov)
- Suspend quirk to save/restore NVS memory over S3 transitions for
Lenovo G50-45 (Zhang Rui)
- Message formatting fix for the ACPI APEI code (Colin Ian King)"
* tag 'acpi-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (32 commits)
ACPICA: Update version to 20170119
ACPICA: Tools: Update common signon, remove compilation bit width
ACPICA: Source tree: Update copyright notices to 2017
ACPICA: Linuxize: Restore and fix Intel compiler build
x86/ACPI: keep x86_cpu_to_acpiid mapping valid on CPU hotplug
spi: acpi: Initialize modalias from of_compatible
i2c: acpi: Initialize info.type from of_compatible
ACPI / bus: Introduce acpi_of_modalias() equiv of of_modalias_node()
ACPI: save NVS memory for Lenovo G50-45
ACPI, APEI, EINJ: fix malformed newline escape
ACPI / button: Remove lid_init_state=method mode
ACPI / button: Change default behavior to lid_init_state=open
ACPI / EC: Use busy polling mode when GPE is not enabled
ACPI / EC: Remove old CLEAR_ON_RESUME quirk
ACPICA: Update version to 20161222
ACPICA: Parser: Update parse info table for some operators
ACPICA: Fix a problem with recent extra support for control method invocations
ACPICA: Parser: Allow method invocations as target operands
ACPICA: Fix for implicit result conversion for the ToXXX functions
ACPICA: Resources: Not a valid resource if buffer length too long
..
When using devicetree spi_device.modalias is set to the compatible
string with the vendor prefix removed. For SPI devices described via
ACPI the spi_device.modalias string is initialized by acpi_device_hid.
When using ACPI and DT ids this string ends up something like "PRP0001".
Change acpi_register_spi_device to use the of_compatible property if
present. This makes it easier to instantiate spi drivers through ACPI
with DT ids.
Signed-off-by: Dan O'Donovan <dan@emutex.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Make sure to release the device-node reference taken in
of_register_spi_device() on errors and when deregistering the device.
Fixes: 284b018973 ("spi: Add OF binding support for SPI busses")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Back before commit 1dccb598df ("arm64: simplify dma_get_ops"), for
arm64, devices for which dma_ops were not explicitly set were automatically
configured to use swiotlb_dma_ops, since this was hard-coded as the
global "dma_ops" in arm64_dma_init().
Now that global "dma_ops" has been removed, all devices much have their
dma_ops explicitly set by a call to arch_setup_dma_ops(), otherwise the
device is assigned dummy_dma_ops, and thus calls to map_sg for such a
device will fail (return 0).
Mediatek SPI uses DMA but does not use a dma channel. Support for this
was added by commit c37f45b5f1 ("spi: support spi without dma channel
to use can_dma()"), which uses the master_spi dev to DMA map buffers.
The master_spi device is not a platform device, rather it is created
in spi_alloc_device(), and therefore its dma_ops are never set.
Therefore, when the mediatek SPI driver when it does DMA (for large SPI
transactions > 32 bytes), SPI will use spi_map_buf()->dma_map_sg() to
map the buffer for use in DMA. But dma_map_sg()->dma_map_sg_attrs() returns
0, because ops->map_sg is dummy_dma_ops->__dummy_map_sg, and hence
spi_map_buf() returns -ENOMEM (-12).
Fix this by using the real spi_master's parent device which should be a
real physical device with DMA properties.
Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Fixes: c37f45b5f1 ("spi: support spi without dma channel to use can_dma()")
Cc: Leilk Liu <leilk.liu@mediatek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus reuse the corresponding function "kcalloc".
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Mark Brown <broonie@kernel.org>
Extract the parsing of SPI slave-specific properties into its own
function, so it can be reused later for SPI slave controllers.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
A null dereference or Oops exception might occurs when reading at once the
whole content of an spi-nor of big enough size that requires an scatterlist
table that does not fit into one single page.
The spi_map_buf function is ignoring the chained sg case by dereferenceing
the scatterlist elements in an array fashion. This wrongly assumes that
the allocation of the scatterlist elements are contiguous. This is true as
long as the scatterlist table fits within a PAGE_SIZE. However, for
allocation where the scatter table is bigger than that, the pages allocated
by sg_alloc might not be contigous.
The sg table can be properly walked by sg_next instead of using an array.
Signed-off-by: Juan Gutierrez <juan.gutierrez@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The spi_transfer parameter delay_usecs allows specifying a time to wait
after transferring a spi message. This wait can be quite long - some
devices, such as some Chrome OS ECs, require as much as 2000 usecs after
a SPI transaction, before it can respond.
(cf: arch/arm64/boot/dts/nvidia/tegra132-norrin.dts:
google,cros-ec-spi-msg-delay = <2000>
)
Blocking a CPU for 2 msecs in a busy loop like this doesn't seem very
friendly to other processes, so change the blocking delay to a sleep
to allow other things to use this CPU (or so it can sleep).
This should be safe to do, because:
(a) A post-transaction delay like this is always specified as a minimum
wait time
(b) A delay here is most likely not very time sensitive, as it occurs
after all data has been transferred
(c) This delay occurs in a non-critical section of the spi worker thread
so where it is safe to sleep.
Two caveats:
1) To avoid penalizing short delays, still use udelay for delays < 10us.
2) usleep_range() very often picks the upper bound, an upper bounds 10%
should be plenty.
Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Instantiated SPI device nodes are marked with OF_POPULATE. This was
introduced in bd6c164. On unloading, loaded device nodes will of course
be unmarked. The problem are nodes that fail during initialisation: If a
node fails, it won't be unloaded and hence not be unmarked.
If a SPI driver module is unloaded and reloaded, it will skip nodes that
failed before.
Skip device nodes that are already populated and mark them only in case
of success.
Note that the same issue exists for I2C.
Fixes: bd6c164 ("spi: Mark instantiated device nodes with OF_POPULATE")
Signed-off-by: Ralf Ramsauer <ralf@ramses-pyramidenbau.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Some SPI masters require slave selection before the transfer
can begin [1]. The SPI framework currently selects the chip using
either 1) the internal CS mechanism or 2) the GPIO CS, but not both.
This patch adds a new master->flags define to indicate both the GPIO
CS and the internal chip select mechanism should be used.
Tested On:
Altera CycloneV development kit
Compile tested for build errors on x86_64 (allyesconfigs)
[1] DesignWare dw_apb_ssi Databook, Version 3.20a (page 39)
Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
A good practice is to prefix the names of functions by the name
of the subsystem.
The kthread worker API is a mix of classic kthreads and workqueues. Each
worker has a dedicated kthread. It runs a generic function that process
queued works. It is implemented as part of the kthread subsystem.
This patch renames the existing kthread worker API to use
the corresponding name from the workqueues API prefixed by
kthread_:
__init_kthread_worker() -> __kthread_init_worker()
init_kthread_worker() -> kthread_init_worker()
init_kthread_work() -> kthread_init_work()
insert_kthread_work() -> kthread_insert_work()
queue_kthread_work() -> kthread_queue_work()
flush_kthread_work() -> kthread_flush_work()
flush_kthread_worker() -> kthread_flush_worker()
Note that the names of DEFINE_KTHREAD_WORK*() macros stay
as they are. It is common that the "DEFINE_" prefix has
precedence over the subsystem names.
Note that INIT() macros and init() functions use different
naming scheme. There is no good solution. There are several
reasons for this solution:
+ "init" in the function names stands for the verb "initialize"
aka "initialize worker". While "INIT" in the macro names
stands for the noun "INITIALIZER" aka "worker initializer".
+ INIT() macros are used only in DEFINE() macros
+ init() functions are used close to the other kthread()
functions. It looks much better if all the functions
use the same scheme.
+ There will be also kthread_destroy_worker() that will
be used close to kthread_cancel_work(). It is related
to the init() function. Again it looks better if all
functions use the same naming scheme.
+ there are several precedents for such init() function
names, e.g. amd_iommu_init_device(), free_area_init_node(),
jump_label_init_type(), regmap_init_mmio_clk(),
+ It is not an argument but it was inconsistent even before.
[arnd@arndb.de: fix linux-next merge conflict]
Link: http://lkml.kernel.org/r/20160908135724.1311726-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/1470754545-17632-3-git-send-email-pmladek@suse.com
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some SPI masters require slave selection before the transfer
can begin [1]. The SPI framework currently selects the chip using
either 1) the internal CS mechanism or 2) the GPIO CS, but not both.
This patch adds a new master->flags define to indicate both the GPIO
CS and the internal chip select mechanism should be used.
Tested On:
Altera CycloneV development kit
Compile tested for build errors on x86_64 (allyesconfigs)
[1] DesignWare dw_apb_ssi Databook, Version 3.20a (page 39)
Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
When reading SPI flash as MTD device, the transfer length is
directly passed to the spi driver. If the requested data size
exceeds 512KB, it will cause the time out calculation to
overflow since transfer length is 32-bit unsigned integer.
This issue is resolved by using 64-bit unsigned integer
to perform the arithmetic.
Signed-off-by: Sien Wu <sien.wu@ni.com>
Acked-by: Brad Keryan <brad.keryan@ni.com>
Acked-by: Gratian Crisan <gratian.crisan@ni.com>
Acked-by: Brad Mouring <brad.mouring@ni.com>
Natinst-ReviewBoard-ID 150232
Signed-off-by: Mark Brown <broonie@kernel.org>
JFFS2 FS might sometime provide kmap'd buffers as destination
buffers to read data from flash. Update spi_map_buf() function to
generate sg_list for such buffers, so that SPI controllers drivers can
use DMA to read data into such buffers.
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
A couple of error paths were missing drops of io_mutex.
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
Quite a lot of cleanup and maintainence work going on this release in
various drivers, and also a fix for a nasty locking issue in the core:
- A fix for locking issues when external drivers explicitly locked the
bus with spi_bus_lock() - we were using the same lock to both control
access to the physical bus in multi-threaded I/O operations and
exclude multiple callers. Confusion between these two caused us to
have scenarios where we were dropping locks. These are fixed by
splitting into two separate locks like should have been done
originally, making everything much clearer and correct.
- Support for DMA in spi_flash_read().
- Support for instantiating spidev on ACPI systems, including some test
devices used in Windows validation.
- Use of the core DMA mapping functionality in the McSPI driver.
- Start of support for ThunderX SPI controllers, involving a very big
set of changes to the Cavium driver.
- Support for Braswell, Exynos 5433, Kaby Lake, Merrifield, RK3036,
RK3228, RK3368 controllers.
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Merge tag 'spi-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi updates from Mark Brown:
"Quite a lot of cleanup and maintainence work going on this release in
various drivers, and also a fix for a nasty locking issue in the core:
- A fix for locking issues when external drivers explicitly locked
the bus with spi_bus_lock() - we were using the same lock to both
control access to the physical bus in multi-threaded I/O operations
and exclude multiple callers.
Confusion between these two caused us to have scenarios where we
were dropping locks. These are fixed by splitting into two
separate locks like should have been done originally, making
everything much clearer and correct.
- Support for DMA in spi_flash_read().
- Support for instantiating spidev on ACPI systems, including some
test devices used in Windows validation.
- Use of the core DMA mapping functionality in the McSPI driver.
- Start of support for ThunderX SPI controllers, involving a very big
set of changes to the Cavium driver.
- Support for Braswell, Exynos 5433, Kaby Lake, Merrifield, RK3036,
RK3228, RK3368 controllers"
* tag 'spi-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (64 commits)
spi: Split bus and I/O locking
spi: octeon: Split driver into Octeon specific and common parts
spi: octeon: Move include file from arch/mips to drivers/spi
spi: octeon: Put register offsets into a struct
spi: octeon: Store system clock freqency in struct octeon_spi
spi: octeon: Convert driver to use readq()/writeq() functions
spi: pic32-sqi: fixup wait_for_completion_timeout return handling
spi: pic32: fixup wait_for_completion_timeout return handling
spi: rockchip: limit transfers to (64K - 1) bytes
spi: xilinx: Return IRQ_NONE if no interrupts were detected
spi: xilinx: Handle errors from platform_get_irq()
spi: s3c64xx: restore removed comments
spi: s3c64xx: add Exynos5433 compatible for ioclk handling
spi: s3c64xx: use error code from clk_prepare_enable()
spi: s3c64xx: rename goto labels to meaningful names
spi: s3c64xx: document the clocks and the clock-name property
spi: s3c64xx: add exynos5433 spi compatible
spi: s3c64xx: fix reference leak to master in s3c64xx_spi_remove()
spi: spi-sh: Remove deprecated create_singlethread_workqueue
spi: spi-topcliff-pch: Remove deprecated create_singlethread_workqueue
...
The current SPI code attempts to use bus_lock_mutex for two purposes. One
is to implement spi_bus_lock() which grants exclusive access to the bus.
The other is to serialize access to the physical hardware. This duplicate
purpose causes confusion which leads to cases where access is not locked
when a caller holds the bus lock mutex. Fix this by splitting out the I/O
functionality into a new io_mutex.
This means taking both mutexes in the DMA path, replacing the existing
mutex with the new I/O one in the message pump (the mutex now always
being taken in the message pump) and taking the bus lock mutex in
spi_sync(), allowing __spi_sync() to have no mutex handling.
While we're at it hoist the mutex further up the message pump before we
power up the device so that all power up/down of the block is covered by
it and there are no races with in-line pumping of messages.
Reported-by: Rich Felker <dalias@libc.org>
Tested-by: Rich Felker <dalias@libc.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch adds supports for SPI device enumeration and removal via
ACPI reconfiguration notifications that are send as a result of an
ACPI table load or unload operation.
The code is very similar with the device tree reconfiguration code
with only small differences in the way we test and set the enumerated
state of the device:
* the equivalent of device tree's OF_POPULATED flag is the
flags.visited field in the ACPI device and the following wrappers
are used to manipulate it: acpi_device_enumerated(),
acpi_device_set_enumerated() and acpi_device_clear_enumerated()
* the device tree code checks of status of the OF_POPULATED flag to
avoid trying to create duplicate Linux devices in two places: once
when the controller is probed, and once when the reconfigure event
is received; in the ACPI code the check is performed only once when
the ACPI namespace is searched because this code path is invoked in
both of the two mentioned cases
The rest of the enumeration handling is similar with device tree: when
the Linux device is unregistered the ACPI device is marked as not
enumerated; also, when a device remove notification is received we
check that the device is in the enumerated state before continuing
with the removal of the Linux device.
Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Few SPI devices provide accelerated read interfaces to read from
SPI-NOR flash devices. These hardwares also support DMA to transfer data
from flash to memory either via mem-to-mem DMA or dedicated slave DMA
channels. Hence, add support for DMA in order to improve throughput and
reduce CPU load.
Use spi_map_buf() to get sg table for the buffer and pass it to SPI
driver.
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This fixes a simple typo in one of the comments.
Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Current spi_map_buf() implementation supports creates sg_table for
vmalloc'd and kmalloc'd buffers. Therefore return error if kmap'd buffer
(or any other buffer) is passed to spi_map_buf().
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Let all SPI masters ignore their children: when it comes
to power management: SPI children have no business doing
keeping their parents awake: they are completely autonomous
devices that just use their parent to talk, and the latter
usecase must be power managed by the host itself on a
per-message basis.
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
External users may use spi_bus_lock to get exclusive access. This will
also grab the bus_lock_mutex and may therefore result in a deadlock if
__spi_pump_messages also tries to get the mutex.
Therefore adapt spi_pump_messages as well as spi_sync to preset the
bus_locked parameter according to the master->bus_lock_flag.
Fixes: 49023d2e4e ("spi: core: Fix deadlock when sending messages")
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The spi_split_transfers_maxsize() gfp parameter is missing in the
function kernel-doc so building gives the following warning:
.//drivers/spi/spi.c:2359: warning: No description found for parameter 'gfp'
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The device which is actually does DMA may have a limitation of the maximum
segment size. Respect this setting when preparing scatter-gather list.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The function __spi_pump_messages() is called by spi_pump_messages() and
__spi_sync(). The function __spi_sync() has an argument 'bus_locked'
that indicates if it is called with the SPI bus mutex held or not. If
'bus_locked' is false then __spi_sync() will acquire the mutex itself.
Commit 556351f14e ("spi: introduce accelerated read support for spi
flash devices") made a change to acquire the SPI bus mutex within
__spi_pump_messages(). However, this change did not check to see if the
mutex is already held. If __spi_sync() is called with the mutex held
(ie. 'bus_locked' is true), then a deadlock occurs when
__spi_pump_messages() is called.
Fix this deadlock by passing the 'bus_locked' state from __spi_sync() to
__spi_pump_messages() and only acquire the mutex if not already held. In
the case where __spi_pump_messages() is called from spi_pump_messages()
it is assumed that the mutex is not held and so call
__spi_pump_messages() with 'bus_locked' set to false. Finally, move the
unlocking of the mutex to the end of the __spi_pump_messages() function
to simplify the code and only call cond_resched() if there are no
errors.
Fixes: 556351f14e ("spi: introduce accelerated read support for spi flash devices")
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch fix following warnings while make xmldocs.
.//drivers/spi/spi.c:2354: warning: Excess function parameter
'message' description in 'spi_split_transfers_maxsize'
.//drivers/spi/spi.c:2354: warning: Excess function parameter
'max_size' description in 'spi_split_transfers_maxsize'
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
When a controller has only PIO support it is very likely that we will
run into use cases where we spend a very large amount of time consuming
CPU. Code that does this should call cond_resched() every once in a
while to give other tasks more of a chance to run so do that in the main
SPI loop, the overhead is negligable if it's not needed.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add missing docbook documentation for the gfp parameter
in function spi_replace_transfers.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Use min_t(size_t,..) in order to avoid the following
build warning on ARM64:
include/linux/kernel.h:754:17: warning: comparison of distinct pointer types lacks a cast
(void) (&_min1 == &_min2); \
^
drivers/spi/spi.c:2304:17: note: in expansion of macro 'min'
xfers[0].len = min(maxsize, xfer[0].len);
Suggested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Use %zu for printing 'size_t' type in order to fix the following
build warning on ARM64:
drivers/spi/spi.c: In function '__spi_split_transfer_maxsize':
drivers/spi/spi.c:2278:2: warning: format '%i' expects argument of type 'int', but argument 4 has type 'size_t' [-Wformat=]
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
__spi_split_transfer_maxsize() can be made static as it is only
used in this file.
This fixes the following sparse warning:
drivers/spi/spi.c:2266:5: warning: symbol '__spi_split_transfer_maxsize' was not declared. Should it be static?
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
spi_replace_transfers() returns error pointers on error, it never
returns NULL.
Fixes: d9f1212272 ('spi: core: add spi_split_transfers_maxsize')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
In addition to providing direct access to SPI bus, some spi controller
hardwares (like ti-qspi) provide special port (like memory mapped port)
that are optimized to improve SPI flash read performance.
This means the controller can automatically send the SPI signals
required to read data from the SPI flash device.
For this, SPI controller needs to know flash specific information like
read command to use, dummy bytes and address width.
Introduce spi_flash_read() interface to support accelerated read
over SPI flash devices. SPI master drivers can implement this callback to
support interfaces such as memory mapped read etc. m25p80 flash driver
and other flash drivers can call this make use of such interfaces. The
interface should only be used with SPI flashes and cannot be used with
other SPI devices.
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add spi_split_transfers_maxsize method that splits
spi_transfers transparently into multiple transfers
that are below the given max-size.
This makes use of the spi_res framework via
spi_replace_transfers to allocate/free the extra
transfers as well as reverting back the changes applied
while processing the spi_message.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add the spi_replace_transfers method that can get used
to replace some spi_transfers from a spi_message with other
transfers.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
SPI resource management framework used while processing a spi_message
via the spi-core.
The basic idea is taken from devres, but as the allocation may happen
fairly frequently, some provisioning (in the form of an unused spi_device
pointer argument to spi_res_alloc) has been made so that at a later stage
we may implement reuse objects allocated earlier avoiding the repeated
allocation by keeping a cache of objects that we can reuse.
This framework can get used for:
* rewriting spi_messages
* to fullfill alignment requirements of the spi_master HW
* to fullfill transfer length requirements
(e.g: transfers need to be less than 64k)
* consolidate spi_messages with multiple transfers into a single transfer
when the total transfer length is below a threshold.
* reimplement spi_unmap_buf without explicitly needing to check if it has
been mapped
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
In Windows it is up to the SPI host controller driver to handle the ACPI
DeviceSelection as it likes. The SPI core does not take any part in it.
This is different in Linux because we always expect to have chip select in
range of 0 .. master->num_chipselect - 1.
In order to support this in Linux we need a way to allow the driver to
translate between ACPI DeviceSelection field and Linux chip select number
so provide a new optional hook ->fw_translate_cs() that can be used by a
driver to handle translation and call this hook if set during SPI slave
ACPI enumeration.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
A quiet release for SPI, not even many driver updates:
- Add a dummy loopback driver for use in exercising framework features
during development.
- Move the test utilities to tools/ and add support for transferring
data to and from a file instead of stdin and stdout to spidev_test.
- Support for Mediatek MT2701 and Renesas AG5 deices.
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Merge tag 'spi-v4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi updates from Mark Brown:
"A quiet release for SPI, not even many driver updates:
- Add a dummy loopback driver for use in exercising framework
features during development.
- Move the test utilities to tools/ and add support for transferring
data to and from a file instead of stdin and stdout to spidev_test.
- Support for Mediatek MT2701 and Renesas AG5 deices"
* tag 'spi-v4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (69 commits)
spi: loopback: fix typo in MODULE_PARM_DESC
spi: sun4i: Prevent chip-select from being activated twice before a transfer
spi: loopback-test: spi_check_rx_ranges can get always done
spi: loopback-test: rename method spi_test_fill_tx to spi_test_fill_pattern
spi: loopback-test: write rx pattern also when running without tx_buf
spi: fsl-espi: expose maximum transfer size limit
spi: expose master transfer size limitation.
spi: zynq: use to_platform_device()
spi: cadence: use to_platform_device()
spi: mediatek: Add spi support for mt2701 IC
spi: mediatek: merge all identical compat to mtk_common_compat
spi: mtk: Add bindings for mediatek MT2701 soc platform
spi: mediatek: Prevent overflows in FIFO transfers
spi: s3c64xx: Remove unused platform_device_id entries
spi: use to_spi_device
spi: dw: Use SPI_TMOD_TR rather than magic const 0 to set tmode
spi: imx: defer spi initialization, if DMA engine is
spi: imx: return error from dma channel request
spi: imx: enable loopback only for ECSPI controller family
spi: imx: fix loopback mode setup after controller reset
...
spi->irq was ignoring GpioInt property setting it to -1.
acpi_dev_gpio_irq_get returns and configure the slave IRQ according to
the ACPI slave node description.
It is now inline with devicetree behavior.
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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
Mark (and unmark) device nodes with the POPULATE flag as appropriate.
This is required to avoid multi probing when enabling and populating SPI
buses in DT overlays.
Based on commit 4f001fd301 ("i2c: Mark instantiated device nodes
with OF_POPULATE").
Suggested-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Uninline spi_unregister_device() in preparation of adding more code to
it. Add kerneldoc documentation while we're at it.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@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>