This patch introduces a completion that is completed in
spi_finalize_current_message() and waited for in
__spi_pump_transfer_message(). This way all manipulation of ctlr->cur_msg
is done with the io_mutex held and strictly ordered:
__spi_pump_transfer_message() will not return until
spi_finalize_current_message() is done using ctlr->cur_msg, and its
calling context is only touching ctlr->cur_msg after returning.
Due to this, we can safely drop the spin-locks around ctlr->cur_msg.
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220621061234.3626638-11-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
Since the whole idling transition is locked by the io_mutex now, there is
no need to check this flag anymore.
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220621061234.3626638-7-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
Now that the idling flag is wholly behind the io_mutex, this broken piece
of code can be safely removed.
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220621061234.3626638-6-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
The interaction with the controller message queue and its corresponding
auxiliary flags and variables requires the use of the queue_lock which is
costly. Since spi_sync will transfer the complete message anyway, and not
return until it is finished, there is no need to put the message into the
queue if the queue is empty. This can save a lot of overhead.
As an example of how significant this is, when using the MCP2518FD SPI CAN
controller on a i.MX8MM SoC, the time during which the interrupt line
stays active (during 3 relatively short spi_sync messages), is reduced
from 98us to 72us by this patch.
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220621061234.3626638-3-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
This enables the possibility to transfer a message that is not at the
current tip of the async message queue.
This is in preparation of the next patch(es) which enable spi_sync messages
to skip the queue altogether.
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220621061234.3626638-2-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
Return -ENOMEM if the allocation fails. Don't return success.
Fixes: 6598b91b5a ("spi: spi.c: Convert statistics to per-cpu u64_stats_t")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/Yqh6bdNYO2XNhPBa@kili
Signed-off-by: Mark Brown <broonie@kernel.org>
We have already a helper to get the first child device, use it and
drop custom approach.
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220610120219.18988-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On 32 bit systems, the following kernel BUG is hit:
BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1
caller is debug_smp_processor_id+0x18/0x24
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.19.0-rc1-00001-g6ae0aec8a366 #181
Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
Backtrace:
dump_backtrace from show_stack+0x20/0x24
r7:81024ffd r6:00000000 r5:81024ffd r4:60000013
show_stack from dump_stack_lvl+0x60/0x78
dump_stack_lvl from dump_stack+0x14/0x1c
r7:81024ffd r6:80f652de r5:80bec180 r4:819a2500
dump_stack from check_preemption_disabled+0xc8/0xf0
check_preemption_disabled from debug_smp_processor_id+0x18/0x24
r8:8119b7e0 r7:81205534 r6:819f5c00 r5:819f4c00 r4:c083d724
debug_smp_processor_id from __spi_sync+0x78/0x220
__spi_sync from spi_sync+0x34/0x4c
r10:bb7bf4e0 r9:c083d724 r8:00000007 r7:81a068c0 r6:822a83c0 r5:c083d724
r4:819f4c00
spi_sync from spi_mem_exec_op+0x338/0x370
r5:000000b4 r4:c083d910
spi_mem_exec_op from spi_nor_read_id+0x98/0xdc
r10:bb7bf4e0 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:82358040
r4:819f7c40
spi_nor_read_id from spi_nor_detect+0x38/0x114
r7:82358040 r6:00000000 r5:819f7c40 r4:819f7c40
spi_nor_detect from spi_nor_scan+0x11c/0xbec
r10:bb7bf4e0 r9:00000000 r8:00000000 r7:c083da4c r6:00000000 r5:00010101
r4:819f7c40
spi_nor_scan from spi_nor_probe+0x10c/0x2d0
r10:bb7bf4e0 r9:bb7bf4d0 r8:00000000 r7:819f4c00 r6:00000000 r5:00000000
r4:819f7c40
per-cpu access needs to be guarded against preemption.
Fixes: 6598b91b5a ("spi: spi.c: Convert statistics to per-cpu u64_stats_t")
Reported-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David Jander <david@protonic.nl>
Tested-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Link: https://lore.kernel.org/r/20220609121334.2984808-1-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
This change gives a dramatic performance improvement in the hot path,
since many costly spin_lock_irqsave() calls can be avoided.
On an i.MX8MM system with a MCP2518FD CAN controller connected via SPI,
the time the driver takes to handle interrupts, or in other words the time
the IRQ line of the CAN controller stays low is mainly dominated by the
time it takes to do 3 relatively short sync SPI transfers. The effect of
this patch is a reduction of this time from 136us down to only 98us.
Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220524091808.2269898-1-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
Here is the set of driver core changes for 5.19-rc1.
Note, I'm not really happy with this pull request as-is, see below for
details, but overall this is all good for everything but a small set of
systems, which we have a fix for already.
Lots of tiny driver core changes and cleanups happened this cycle,
but the two major things were:
- firmware_loader reorganization and additions including the
ability to have XZ compressed firmware images and the ability
for userspace to initiate the firmware load when it needs to,
instead of being always initiated by the kernel. FPGA devices
specifically want this ability to have their firmware changed
over the lifetime of the system boot, and this allows them to
work without having to come up with yet-another-custom-uapi
interface for loading firmware for them.
- physical location support added to sysfs so that devices that
know this information, can tell userspace where they are
located in a common way. Some ACPI devices already support
this today, and more bus types should support this in the
future.
Smaller changes included:
- driver_override api cleanups and fixes
- error path cleanups and fixes
- get_abi script fixes
- deferred probe timeout changes.
It's that last change that I'm the most worried about. It has been
reported to cause boot problems for a number of systems, and I have a
tested patch series that resolves this issue. But I didn't get it
merged into my tree before 5.18-final came out, so it has not gotten any
linux-next testing.
I'll send the fixup patches (there are 2) as a follow-on series to this
pull request if you want to take them directly, _OR_ I can just revert
the probe timeout changes and they can wait for the next -rc1 merge
cycle. Given that the fixes are tested, and pretty simple, I'm leaning
toward that choice. Sorry this all came at the end of the merge window,
I should have resolved this all 2 weeks ago, that's my fault as it was
in the middle of some travel for me.
All have been tested in linux-next for weeks, with no reported issues
other than the above-mentioned boot time outs.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the set of driver core changes for 5.19-rc1.
Lots of tiny driver core changes and cleanups happened this cycle, but
the two major things are:
- firmware_loader reorganization and additions including the ability
to have XZ compressed firmware images and the ability for userspace
to initiate the firmware load when it needs to, instead of being
always initiated by the kernel. FPGA devices specifically want this
ability to have their firmware changed over the lifetime of the
system boot, and this allows them to work without having to come up
with yet-another-custom-uapi interface for loading firmware for
them.
- physical location support added to sysfs so that devices that know
this information, can tell userspace where they are located in a
common way. Some ACPI devices already support this today, and more
bus types should support this in the future.
Smaller changes include:
- driver_override api cleanups and fixes
- error path cleanups and fixes
- get_abi script fixes
- deferred probe timeout changes.
It's that last change that I'm the most worried about. It has been
reported to cause boot problems for a number of systems, and I have a
tested patch series that resolves this issue. But I didn't get it
merged into my tree before 5.18-final came out, so it has not gotten
any linux-next testing.
I'll send the fixup patches (there are 2) as a follow-on series to this
pull request.
All have been tested in linux-next for weeks, with no reported issues
other than the above-mentioned boot time-outs"
* tag 'driver-core-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits)
driver core: fix deadlock in __device_attach
kernfs: Separate kernfs_pr_cont_buf and rename_lock.
topology: Remove unused cpu_cluster_mask()
driver core: Extend deferred probe timeout on driver registration
MAINTAINERS: add Russ Weight as a firmware loader maintainer
driver: base: fix UAF when driver_attach failed
test_firmware: fix end of loop test in upload_read_show()
driver core: location: Add "back" as a possible output for panel
driver core: location: Free struct acpi_pld_info *pld
driver core: Add "*" wildcard support to driver_async_probe cmdline param
driver core: location: Check for allocations failure
arch_topology: Trace the update thermal pressure
kernfs: Rename kernfs_put_open_node to kernfs_unlink_open_file.
export: fix string handling of namespace in EXPORT_SYMBOL_NS
rpmsg: use local 'dev' variable
rpmsg: Fix calling device_lock() on non-initialized device
firmware_loader: describe 'module' parameter of firmware_upload_register()
firmware_loader: Move definitions from sysfs_upload.h to sysfs.h
firmware_loader: Fix configs for sysfs split
selftests: firmware: Add firmware upload selftests
...
A couple of fixes that came in during the merge window, a driver
fix for spurious timeouts in the fsi driver and an improvement to
make the core display error messages for transfer_one_message()
to help people debug things.
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Merge tag 'spi-fix-v5.19-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi fixes from Mark Brown:
"A couple of fixes that came in during the merge window: a driver fix
for spurious timeouts in the fsi driver and an improvement to make the
core display error messages for transfer_one_message() to help people
debug things"
* tag 'spi-fix-v5.19-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: core: Display return code when failing to transfer message
spi: fsi: Fix spurious timeout
All the other calls to the controller driver display the error
return code. The return code is helpful to understand what went
wrong, so include it when failing to transfer one message.
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20220525165852.33167-3-eajames@linux.ibm.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This is quite a quiet release but some new drivers mean that the
diffstat is fairly large, the new drivers include the aspeed driver
which is migrated from MTD as part of the ongoing move of controllers
with specialised support for SPI flashes into the SPI subsystem.
- Support for devices which flip CPHA during recieve only transfers
(eg, if MOSI and MISO have inverted polarity).
- Overhaul of the i.MX driver, including the addition of PIO support
for better performance on small transfers.
- Migration of the Aspeed driver from MTD.
- Support for Aspeed AST2400, Ingenic JZ4775 and X1/2000 and MediaTek
IPM and SFI.
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Merge tag 'spi-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi updates from Mark Brown:
"This is quite a quiet release but some new drivers mean that the
diffstat is fairly large. The new drivers include the aspeed driver
which is migrated from MTD as part of the ongoing move of controllers
with specialised support for SPI flashes into the SPI subsystem.
- Support for devices which flip CPHA during recieve only transfers
(eg, if MOSI and MISO have inverted polarity).
- Overhaul of the i.MX driver, including the addition of PIO support
for better performance on small transfers.
- Migration of the Aspeed driver from MTD.
- Support for Aspeed AST2400, Ingenic JZ4775 and X1/2000 and MediaTek
IPM and SFI"
* tag 'spi-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (84 commits)
spi: spi-au1550: replace ternary operator with min()
mtd: spi-nor: aspeed: set the decoding size to at least 2MB for AST2600
spi: aspeed: Calibrate read timings
spi: aspeed: Add support for the AST2400 SPI controller
spi: aspeed: Workaround AST2500 limitations
spi: aspeed: Adjust direct mapping to device size
spi: aspeed: Add support for direct mapping
spi: spi-mem: Convert Aspeed SMC driver to spi-mem
spi: Convert the Aspeed SMC controllers device tree binding
spi: spi-cadence: Update ISR status variable type to irqreturn_t
spi: Doc fix - Describe add_lock and dma_map_dev in spi_controller
spi: cadence-quadspi: Handle spi_unregister_master() in remove()
spi: stm32-qspi: Remove SR_BUSY bit check before sending command
spi: stm32-qspi: Always check SR_TCF flags in stm32_qspi_wait_cmd()
spi: stm32-qspi: Fix wait_cmd timeout in APM mode
spi: cadence-quadspi: remove unnecessary (void *) casts
spi: cadence-quadspi: Add missing blank line in cqspi_request_mmap_dma()
spi: spi-imx: mx51_ecspi_prepare_message(): skip writing MX51_ECSPI_CONFIG register if unchanged
spi: spi-imx: add PIO polling support
spi: spi-imx: replace struct spi_imx_data::bitbang by pointer to struct spi_controller
...
Use a helper to set driver_override to the reduce amount of duplicated
code.
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220419113435.246203-8-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Using pm_runtime_resume_and_get is more appropriate
for simplifing code
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
Link: https://lore.kernel.org/r/20220418110226.2559081-1-chi.minghao@zte.com.cn
Signed-off-by: Mark Brown <broonie@kernel.org>
The previous commit that made bits-per-word validation conditional
results in leaving no unconditional affectation of the status variable.
Since the variable is returned at the end of the function, initialize
it to avoid returning an undefined value.
Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Fixes: b3fe2e5167 ("spi: core: Only check bits_per_word validity when explicitly provided")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20220414084040.975520-1-paul.kocialkowski@bootlin.com
Signed-off-by: Mark Brown <broonie@kernel.org>
On SPI device probe, the core will call spi_setup in spi_add_device
before the corresponding driver was probed. When this happens, the
bits_per_word member of the device is not yet set by the driver,
resulting in the default being set to 8 bits-per-word.
However some controllers do not support 8 bits-per-word at all, which
results in a failure when checking the bits-per-word validity.
In order to support these devices, skip the bits-per-word validity
check when it is not explicitly provided by drivers.
Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Link: https://lore.kernel.org/r/20220412122207.130181-1-paul.kocialkowski@bootlin.com
Signed-off-by: Mark Brown <broonie@kernel.org>
- Revert an ACPI processor driver change related to cache
invalidation in acpi_idle_play_dead() that clearly was a mistake
and introduced user-visible regressions (Akihiko Odaki).
- Replace the last instance of acpi_bus_get_device() added during
the recent merge window and drop the function to prevent more
users of it from being added (Rafael Wysocki).
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Merge tag 'acpi-5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI updates from Rafael Wysocki:
"These revert a problematic commit from the 5.17 development cycle and
finalize the elimination of acpi_bus_get_device() that mostly took
place during the recent merge window.
Specifics:
- Revert an ACPI processor driver change related to cache
invalidation in acpi_idle_play_dead() that clearly was a mistake
and introduced user-visible regressions (Akihiko Odaki).
- Replace the last instance of acpi_bus_get_device() added during the
recent merge window and drop the function to prevent more users of
it from being added (Rafael Wysocki)"
* tag 'acpi-5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: bus: Eliminate acpi_bus_get_device()
Revert "ACPI: processor: idle: Only flush cache on entering C3"
Commit b470e10eb4 ("spi: core: add dma_map_dev for dma device") added
dma_map_dev for _spi_map_msg() but missed to add for unmap routine,
__spi_unmap_msg(), so add it now.
Fixes: b470e10eb4 ("spi: core: add dma_map_dev for dma device")
Cc: stable@vger.kernel.org # v5.14+
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20220406132238.1029249-1-vkoul@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Replace the last instance of acpi_bus_get_device(), added recently
by commit 87e59b36e5 ("spi: Support selection of the index of the
ACPI Spi Resource before alloc"), with acpi_fetch_acpi_dev() and
finally drop acpi_bus_get_device() that has no more users.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
While computing sgs in spi_map_buf(), the data type
used in min_t() for max_seg_size is 'unsigned int' where
as that of ctlr->max_dma_len is 'size_t'.
min_t(unsigned int,x,y) gives wrong results if one of x/y is
'size_t'
Consider the below examples on a 64-bit machine (ie size_t is
64-bits, and unsigned int is 32-bit).
case 1) min_t(unsigned int, 5, 0x100000001);
case 2) min_t(size_t, 5, 0x100000001);
Case 1 returns '1', where as case 2 returns '5'. As you can see
the result from case 1 is wrong.
This patch fixes the above issue by using the data type of the
parameters that are used in min_t with maximum data length.
Fixes: commit 1a4e53d2fc ("spi: Fix invalid sgs value")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20220316175317.465-1-biju.das.jz@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>
max_seg_size is unsigned int and it can have a value up to 2^32
(for eg:-RZ_DMAC driver sets dma_set_max_seg_size as U32_MAX)
When this value is used in min_t() as an integer type, it becomes
-1 and the value of sgs becomes 0.
Fix this issue by replacing the 'int' data type with 'unsigned int'
in min_t().
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20220307184843.9994-1-biju.das.jz@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit d40f0b6f2e instroduced last_cs_enable to avoid setting
chipselect if it's not necessary, but it also introduces a bug. The
chipselect may not be set correctly on multi-device SPI busses. The
reason is that we can't judge the chipselect by bool last_cs_enable,
since chipselect may be modified after other devices were accessed.
So we should record the specific state of chipselect in case of
confusion.
Signed-off-by: Yun Zhou <yun.zhou@windriver.com>
Link: https://lore.kernel.org/r/20220217141234.72737-1-yun.zhou@windriver.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Use dedicated function sysfs_emit() that does some extra checking,
e.g. to ensure that no more than PAGESIZE bytes are written.
In addition add a trailing newline to the output, that makes it
better readable from the console.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/56e1588d-d53b-73e9-fdc8-7fe30bf91f11@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
All drivers using GPIOs as chip select have been rewritten to use
GPIO descriptors passing the ->use_gpio_descriptors flag. Retire
the code and fields used by the legacy GPIO API.
Do not drop the ->use_gpio_descriptors flag: it now only indicates
that we want to use GPIOs in addition to native chip selects.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220210231954.807904-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Merge series from Uwe Kleine-König <u.kleine-koenig@pengutronix.de>:
this series goal is to change the spi remove callback's return value to void.
After numerous patches nearly all drivers already return 0 unconditionally.
The four first patches in this series convert the remaining three drivers to
return 0, the final patch changes the remove prototype and converts all
implementers.
base-commit: 26291c54e1
The value returned by an spi driver's remove function is mostly ignored.
(Only an error message is printed if the value is non-zero that the
error is ignored.)
So change the prototype of the remove function to return no value. This
way driver authors are not tempted to assume that passing an error to
the upper layer is a good idea. All drivers are adapted accordingly.
There is no intended change of behaviour, all callbacks were prepared to
return 0 before.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Claudius Heine <ch@denx.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC
Acked-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Acked-by: Łukasz Stelmach <l.stelmach@samsung.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220123175201.34839-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Replace acpi_bus_get_device() that is going to be dropped with
acpi_fetch_acpi_dev().
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/2231987.ElGaqSPkdT@kreacher
Signed-off-by: Mark Brown <broonie@kernel.org>
Some ACPI nodes may have more than one Spi Resource.
To be able to handle these case, its necessary to have
a way of counting these resources.
Signed-off-by: Stefan Binding <sbinding@opensource.cirrus.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20220121172431.6876-5-sbinding@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
If a node contains more than one SPI resource it may be necessary to
use an index to select which one you want to allocate a spi device for.
Signed-off-by: Stefan Binding <sbinding@opensource.cirrus.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20220121172431.6876-4-sbinding@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This can then be used to find a spi resource inside an
ACPI node, and allocate a spi device.
Signed-off-by: Stefan Binding <sbinding@opensource.cirrus.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20220121172431.6876-3-sbinding@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This functions were previously made private since they
were not used. However, these functions will be needed
again.
Partial revert of commit da21fde0fd
("spi: Make several public functions private to spi.c")
Signed-off-by: Stefan Binding <sbinding@opensource.cirrus.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20220121172431.6876-2-sbinding@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit b42faeee71 ("spi: Add a PTP system timestamp
to the transfer structure") added an include of ptp_clock_kernel.h
to spi.h for struct ptp_system_timestamp but a forward declaration
is enough. Let's use that to limit the number of objects we have
to rebuild every time we touch networking headers.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20210904013140.2377609-1-kuba@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Move the cs_setup delay to the end of spi_set_cs.
From include/linux/spi/spi.h:
* @cs_setup: delay to be introduced by the controller after CS is
asserted
The cs_setup delay needs to happen *after* CS is asserted, that is, at
the end of spi_set_cs, not at the beginning. Otherwise we're just
delaying before the SPI transaction starts at all, which isn't very
useful.
No drivers use this right now, but that is likely to change soon with an
upcoming Apple SPI HID transport driver.
Fixes: 25093bdeb6 ("spi: implement SW control for CS times")
Signed-off-by: Hector Martin <marcan@marcan.st>
Link: https://lore.kernel.org/r/20211210170534.177139-1-marcan@marcan.st
Signed-off-by: Mark Brown <broonie@kernel.org>
The recent commit 3f07657506 ("spi: deduplicate spi_match_id()
in __spi_register_driver()") inadvertently inverted a condition
that provokes a (harmless) warning:
WARNING KERN SPI driver mtd_dataflash has no spi_device_id for atmel,at45
Restore logic to avoid such warning to be issued.
Fixes: 3f07657506 ("spi: deduplicate spi_match_id() in __spi_register_driver()")
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://lore.kernel.org/r/20211123170034.41253-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
/*
* Fix multi-line comment style as in this short example. Pay attention
* to the capitalization, period and starting line of the text.
*/
While at it, split the (supposedly short) description of couple of functions
to summary (short description) and (long) description.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211122171721.61553-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
krealloc() as any other kernel memory allocation calls accepts GFP flags,
one of which is __GFP_ZERO. Hence, no need to call memset() explicitly on
the reallocated buffer.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211122171721.61553-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The same logic is used in spi_match_id() and in the __spi_register_driver().
By switching the former from taking struct spi_device * to const char * as
the second parameter we may deduplicate the code.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211119173718.52938-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit 6098475d4c ("spi: Fix deadlock when adding SPI controllers on
SPI buses") introduced a per-controller mutex. But mutex_unlock() of
said lock is called after the controller is already freed:
spi_unregister_controller(ctlr)
-> put_device(&ctlr->dev)
-> spi_controller_release(dev)
-> mutex_unlock(&ctrl->add_lock)
Move the put_device() after the mutex_unlock().
Fixes: 6098475d4c ("spi: Fix deadlock when adding SPI controllers on SPI buses")
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v5.15
Link: https://lore.kernel.org/r/20211111083713.3335171-1-michael@walle.cc
Signed-off-by: Mark Brown <broonie@kernel.org>
This is quite a quiet release for SPI, there's been a bit of cleanup to
the core from Uwe but nothing functionality wise. We have added several
new drivers, Cadence XSPI, Ingenic JZ47xx, Qualcomm SC7280 and SC7180
and Xilinx Versal OSPI.
There's a trivial conflict in the Tegra driver that's been causing
issues.
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Merge tag 'spi-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi updates from Mark Brown:
"This is quite a quiet release for SPI, there's been a bit of cleanup
to the core from Uwe but nothing functionality wise.
We have added several new drivers, Cadence XSPI, Ingenic JZ47xx,
Qualcomm SC7280 and SC7180 and Xilinx Versal OSPI"
* tag 'spi-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (41 commits)
spi: Convert NXP flexspi to json schema
spi: spi-geni-qcom: Add support for GPI dma
spi: fsi: Fix contention in the FSI2SPI engine
spi: spi-rpc-if: Check return value of rpcif_sw_init()
spi: tegra210-quad: Put device into suspend on driver removal
spi: tegra20-slink: Put device into suspend on driver removal
spi: bcm-qspi: Fix missing clk_disable_unprepare() on error in bcm_qspi_probe()
spi: at91-usart: replacing legacy gpio interface for gpiod
spi: replace snprintf in show functions with sysfs_emit
spi: cadence: Add of_node_put() before return
spi: orion: Add of_node_put() before goto
spi: cadence-quadspi: fix dma_unmap_single() call
spi: tegra20: fix build with CONFIG_PM_SLEEP=n
spi: bcm-qspi: add support for 3-wire mode for half duplex transfer
spi: bcm-qspi: Add mspi spcr3 32/64-bits xfer mode
spi: Make several public functions private to spi.c
spi: Reorder functions to simplify the next commit
spi: Remove unused function spi_busnum_to_master()
spi: Move comment about chipselect check to the right place
spi: fsi: Print status on error
...
io_mutex is taken by spi_setup() and spi-mux's .setup() callback calls
spi_setup() which results in a nested lock of io_mutex.
add_lock is taken by spi_add_device(). The device_add() call in there
can result in calling spi-mux's .probe() callback which registers its
own spi controller which in turn results in spi_add_device() being
called again.
To fix this initialize the controller's locks already in
spi_alloc_controller() to give spi_mux_probe() a chance to set the
lockdep subclass.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20211013133710.2679703-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently we have a global spi_add_lock which we take when adding new
devices so that we can check that we're not trying to reuse a chip
select that's already controlled. This means that if the SPI device is
itself a SPI controller and triggers the instantiation of further SPI
devices we trigger a deadlock as we try to register and instantiate
those devices while in the process of doing so for the parent controller
and hence already holding the global spi_add_lock. Since we only care
about concurrency within a single SPI bus move the lock to be per
controller, avoiding the deadlock.
This can be easily triggered in the case of spi-mux.
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
All these functions have no callers apart from drivers/spi/spi.c. So
drop their declarations in include/linux/spi/spi.h and don't export
them.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20211007121415.2401638-5-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently the "Core methods for SPI resource management" are exported
and public functions. They are however only used in drivers/spi/spi.c.
To allow to drop the global declarations and not to have to insert local
ones instead, move them before their users.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20211007121415.2401638-4-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
The part of the comment about locking isn't that relevant compared to
the chip select check. So drop the sentence about locking.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20211007121415.2401638-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently for SPI devices we use the spi_device_id for module autoloading
even on systems using device tree, meaning that listing a compatible string
in the of_match_table isn't enough to have the module for a SPI driver
autoloaded.
We attempted to fix this by generating OF based modaliases for devices
instantiated from DT in 3ce6c9e261 ("spi: add of_device_uevent_modalias
support") but this meant we no longer reported spi_device_id based aliases
which broke drivers such as spi-nor which don't list all the compatible
strings they support directly for DT, and in at least that case it's not
super practical to do so given the very large number of compatibles
needed, much larger than the number spi_device_ids due to vendor strings.
As a result fell back to using spi_device_id based modalises.
Try to close the gap by printing a warning when a SPI driver has a DT
compatible that won't be matched as a SPI device ID with the goal of having
drivers provide both. Given fallback compatibles this check is going to be
excessive but it should be robust which is probably more important here.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210921192149.50740-1-broonie@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
During the v5.13 cycle we updated the SPI subsystem to generate OF style
modaliases for SPI devices, replacing the old Linux style modalises we
used to generate based on spi_device_id which are the DT style name with
the vendor removed. Unfortunately this means that we start only
reporting OF style modalises and not the old ones and there is nothing
that ensures that drivers list every possible OF compatible string in
their OF ID table. The result is that there are systems which have been
relying on loading modules based on the old style that are now broken,
as found by Russell King with spi-nor on Macchiatobin.
spi-nor is a particularly problematic case for this, it only lists a
single generic DT compatible jedec,spi-nor in the driver but supports a
huge raft of device specific compatibles, with a large set of part
numbers many of which are offered by multiple vendors. Russell's
searches of upstream device trees has turned up examples with vendor
names written in non-standard ways too. To make matters worse up until
8ff16cf77c ("Documentation: devicetree: m25p80: add "nor-jedec"
binding") the generic compatible was not part of the binding so there
are device trees out there written to that binding version which don't
list it all. The sheer number of parts supported together with our
previous approach of ignoring the vendor ID makes robustly fixing this
by adding compatibles to the spi-nor driver seem problematic, the
current DT binding document does not list all the parts supported by the
driver at the minute (further patches will fix this).
I've also investigated supporting both formats of modalias
simultaneously but that doesn't seem possible, especially without
breaking our userspace ABI which is obviously not viable.
Instead revert the relevant changes for now:
e09f2ab8ee ("spi: update modalias_show after of_device_uevent_modalias support")
3ce6c9e261 ("spi: add of_device_uevent_modalias support")
This will unfortunately mean that any system which had started having
modules autoload based on the OF compatibles for drivers that list
things there but not in the spi_device_ids will now not have those
modules load which is itself a regression. Since it affects a narrower
time window and the particularly problematic spi-nor driver may be
critical to system boot on smaller systems this seems the best of a
series of bad options. I will start an audit of SPI drivers to identify
and fix cases where things won't autoload using spi_device_id, this is
not great but seems to be the best way forward that anyone has been able
to identify.
Thanks to Russell for both his report and the additional diagnostic and
analysis work he has done here, the detailed research above was his
work.
Fixes: e09f2ab8ee ("spi: update modalias_show after of_device_uevent_modalias support")
Fixes: 3ce6c9e261 ("spi: add of_device_uevent_modalias support")
Reported-by: Russell King (Oracle) <linux@armlinux.org.uk>
Suggested-by: Russell King (Oracle) <linux@armlinux.org.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>
Tested-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Cc: Andreas Schwab <schwab@suse.de>
Cc: Marco Felsch <m.felsch@pengutronix.de>
Here is the big set of driver core patches for 5.15-rc1.
These do change a number of different things across different
subsystems, and because of that, there were 2 stable tags created that
might have already come into your tree from different pulls that did the
following
- changed the bus remove callback to return void
- sysfs iomem_get_mapping rework
The latter one will cause a tiny merge issue with your tree, as there
was a last-minute fix for this in 5.14 in your tree, but the fixup
should be "obvious". If you want me to provide a fixed merge for this,
please let me know.
Other than those two things, there's only a few small things in here:
- kernfs performance improvements for huge numbers of sysfs
users at once
- tiny api cleanups
- other minor changes
All of these have been in linux-next for a while with no reported
problems, other than the before-mentioned merge issue.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the big set of driver core patches for 5.15-rc1.
These do change a number of different things across different
subsystems, and because of that, there were 2 stable tags created that
might have already come into your tree from different pulls that did
the following
- changed the bus remove callback to return void
- sysfs iomem_get_mapping rework
Other than those two things, there's only a few small things in here:
- kernfs performance improvements for huge numbers of sysfs users at
once
- tiny api cleanups
- other minor changes
All of these have been in linux-next for a while with no reported
problems, other than the before-mentioned merge issue"
* tag 'driver-core-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (33 commits)
MAINTAINERS: Add dri-devel for component.[hc]
driver core: platform: Remove platform_device_add_properties()
ARM: tegra: paz00: Handle device properties with software node API
bitmap: extend comment to bitmap_print_bitmask/list_to_buf
drivers/base/node.c: use bin_attribute to break the size limitation of cpumap ABI
topology: use bin_attribute to break the size limitation of cpumap ABI
lib: test_bitmap: add bitmap_print_bitmask/list_to_buf test cases
cpumask: introduce cpumap_print_list/bitmask_to_buf to support large bitmask and list
sysfs: Rename struct bin_attribute member to f_mapping
sysfs: Invoke iomem_get_mapping() from the sysfs open callback
debugfs: Return error during {full/open}_proxy_open() on rmmod
zorro: Drop useless (and hardly used) .driver member in struct zorro_dev
zorro: Simplify remove callback
sh: superhyway: Simplify check in remove callback
nubus: Simplify check in remove callback
nubus: Make struct nubus_driver::remove return void
kernfs: dont call d_splice_alias() under kernfs node lock
kernfs: use i_lock to protect concurrent inode updates
kernfs: switch kernfs to use an rwsem
kernfs: use VFS negative dentry caching
...
A small collection of fixes for SPI, small mostly driver specific things
plus a fix for module autoloading which hadn't been working properly for
DT systems.
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Merge tag 'spi-fix-v5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi fixes from Mark Brown:
"A small collection of fixes for SPI, small mostly driver specific
things plus a fix for module autoloading which hadn't been working
properly for DT systems"
* tag 'spi-fix-v5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: cadence-quadspi: Fix check condition for DTR ops
spi: mediatek: Fix fifo transfer
spi: imx: mx51-ecspi: Fix CONFIGREG delay comment
spi: imx: mx51-ecspi: Fix low-speed CONFIGREG delay calculation
spi: update modalias_show after of_device_uevent_modalias support
spi: meson-spicc: fix memory leak in meson_spicc_remove
spi: spi-mux: Add module info needed for autoloading
As we know, spi core layer has removed spi_set_cs_timing() API.
So this patch moved spi_delay for cs_timing from spi_controller
to spi_device, because cs timing should be set by spi_device but
not controller.
Signed-off-by: Mason Zhang <Mason.Zhang@mediatek.com>
Link: https://lore.kernel.org/r/20210804133716.32040-1-Mason.Zhang@mediatek.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit 3ce6c9e261 ("spi: add of_device_uevent_modalias support") is
incomplete, as it didn't update the modalias_show function to generate the
of: modalias string if available.
Fixes: 3ce6c9e261 ("spi: add of_device_uevent_modalias support")
Signed-off-by: Andreas Schwab <schwab@suse.de>
Link: https://lore.kernel.org/r/mvmwnpi4fya.fsf@suse.de
Signed-off-by: Mark Brown <broonie@kernel.org>
The driver core ignores the return value of this callback because there
is only little it can do when a device disappears.
This is the final bit of a long lasting cleanup quest where several
buses were converted to also return void from their remove callback.
Additionally some resource leaks were fixed that were caused by drivers
returning an error code in the expectation that the driver won't go
away.
With struct bus_type::remove returning void it's prevented that newly
implemented buses return an ignored error code and so don't anticipate
wrong expectations for driver authors.
Reviewed-by: Tom Rix <trix@redhat.com> (For fpga)
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com> (For drivers/s390 and drivers/vfio)
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> (For ARM, Amba and related parts)
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Chen-Yu Tsai <wens@csie.org> (for sunxi-rsb)
Acked-by: Pali Rohár <pali@kernel.org>
Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org> (for media)
Acked-by: Hans de Goede <hdegoede@redhat.com> (For drivers/platform)
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-By: Vinod Koul <vkoul@kernel.org>
Acked-by: Juergen Gross <jgross@suse.com> (For xen)
Acked-by: Lee Jones <lee.jones@linaro.org> (For mfd)
Acked-by: Johannes Thumshirn <jth@kernel.org> (For mcb)
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> (For slimbus)
Acked-by: Kirti Wankhede <kwankhede@nvidia.com> (For vfio)
Acked-by: Maximilian Luz <luzmaximilian@gmail.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> (For ulpi and typec)
Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com> (For ipack)
Acked-by: Geoff Levand <geoff@infradead.org> (For ps3)
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com> (For thunderbolt)
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> (For intel_th)
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net> (For pcmcia)
Acked-by: Rafael J. Wysocki <rafael@kernel.org> (For ACPI)
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org> (rpmsg and apr)
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> (For intel-ish-hid)
Acked-by: Dan Williams <dan.j.williams@intel.com> (For CXL, DAX, and NVDIMM)
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> (For isa)
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (For firewire)
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> (For hid)
Acked-by: Thorsten Scherer <t.scherer@eckelmann.de> (For siox)
Acked-by: Sven Van Asbroeck <TheSven73@gmail.com> (For anybuss)
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> (For MMC)
Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210713193522.1770306-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some controllers like qcom geni need the parent device to be used for
dma mapping, so add a dma_map_dev field and let drivers fill this to be
used as mapping device
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20210625052213.32260-4-vkoul@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
There is an assignment of ancillary->mode to itself which looks
dubious since the proceeding comment states that the speed and
mode is taken over from the SPI main device, indicating that
ancillary->mode should assigned using the value spi->mode.
Fix this.
Addresses-Coverity: ("Self assignment")
Fixes: 0c79378c01 ("spi: add ancillary device support")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20210623172300.161484-1-colin.king@canonical.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Introduce support for ancillary devices, similar to existing
implementation for I2C. This is useful for devices having
multiple chip-selects, for example some microcontrollers
provide a normal SPI interface and a flashing SPI interface.
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://lore.kernel.org/r/20210621175359.126729-2-sebastian.reichel@collabora.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Add OF support as already done for ACPI to take driver
MODULE_DEVICE_TABLE(of, ..) into account.
For example with this change a spi nor device MODALIAS changes from:
MODALIAS=spi:spi-nor
to
MODALIAS=of:Nspi-flashT(null)Cjedec,spi-nor
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Link: https://lore.kernel.org/r/20210525091003.18228-1-m.felsch@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
No one seems to be using this global and exported function, so remove it
as it is no longer needed.
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20210609071918.2852069-1-gregkh@linuxfoundation.org
Signed-off-by: Mark Brown <broonie@kernel.org>
It is helpful to see what state of CS signal was during one
or another SPI operation. All the same for SPI setup.
Enable tracing of the SPI setup and CS selection.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Message-Id: <20210526195655.75691-1-andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
When a spi device is unregistered and triggers a driver unbind, the
driver might need to access the spi device. So, don't have the
controller clean up the spi device before the driver is unbound. Clean
up the spi device after the driver is unbound.
Fixes: c7299fea67 ("spi: Fix spi device unregister flow")
Reported-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20210505164734.175546-1-saravanak@google.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently GPIO CS handling, when descriptors are in use, doesn't
take into consideration that in ACPI case the default polarity
is Active High and can't be altered. Instead we have to use the
per-chip definition provided by SPISerialBus() resource.
Fixes: 766c6b63aa ("spi: fix client driver breakages when using GPIO descriptors")
Cc: Liguang Zhang <zhangliguang@linux.alibaba.com>
Cc: Jay Fang <f.fangjian@huawei.com>
Cc: Sven Van Asbroeck <thesven73@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Xin Hao <xhao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20210511140912.30757-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
We have a lot of hard coded values in nanoseconds or other units.
Use predefined constants to make it more clear.
While at it, add or amend comments in the corresponding functions.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210510131120.49253-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
this patch takes the io_mutex to prevent an unprotected HW
register modification in the set_cs_timing callback.
Fixes: 4cea6b8cc3 ("spi: add power control when set_cs_timing")
Signed-off-by: Leilk Liu <leilk.liu@mediatek.com>
Link: https://lore.kernel.org/r/20210508060214.1485-1-leilk.liu@mediatek.com
Signed-off-by: Mark Brown <broonie@kernel.org>
When an SPI device is unregistered, the spi->controller->cleanup() is
called in the device's release callback. That's wrong for a couple of
reasons:
1. spi_dev_put() can be called before spi_add_device() is called. And
it's spi_add_device() that calls spi_setup(). This will cause clean()
to get called without the spi device ever being setup.
2. There's no guarantee that the controller's driver would be present by
the time the spi device's release function gets called.
3. It also causes "sleeping in atomic context" stack dump[1] when device
link deletion code does a put_device() on the spi device.
Fix these issues by simply moving the cleanup from the device release
callback to the actual spi_unregister_device() function.
[1] - https://lore.kernel.org/lkml/CAHp75Vc=FCGcUyS0v6fnxme2YJ+qD+Y-hQDQLa2JhWNON9VmsQ@mail.gmail.com/
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20210426235638.1285530-1-saravanak@google.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The enable1 is confusing name. Change it to clearly show what is
the intention behind it. No functional changes.
Fixes: 25093bdeb6 ("spi: implement SW control for CS times")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210420131846.75983-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Each time we call spi_get_gpio_descs() the num_chipselect is overwritten
either by new value or by the old one. This is an extra operation in case
gpiod_count() returns an error. Besides that it slashes the error handling
of gpiod_count().
Refactor the code to make error handling of gpiod_count() call cleaner.
Note, that gpiod_count() never returns 0, take this into account as well.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210420164040.40055-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
ffz(), that has been used to count unused native CSs,
might cause undefined behaviour when called against ~0U.
To fix that, open code it with ffs(~value) - 1.
Fixes: 7d93aecdb5 ("spi: Add generic support for unused native cs with cs-gpios")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210420164425.40287-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The commit 7d93aecdb5 ("spi: Add generic support for unused native cs
with cs-gpios") excludes the valid case for the controllers that doesn't
need to switch native CS in order to perform the transfer, i.e. when
0 native
... ...
<n> - 1 native
<n> GPIO
<n> + 1 GPIO
... ...
where <n> defines maximum of native CSs supported by the controller.
To allow this, bail out from spi_get_gpio_descs() conditionally for
the controllers which explicitly marked with SPI_MASTER_GPIO_SS.
Fixes: 7d93aecdb5 ("spi: Add generic support for unused native cs with cs-gpios")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210420164425.40287-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently, the SPI core doesn't set the struct device fwnode pointer
when it creates a new SPI device. This means when the device is
registered the fwnode is NULL and the check in device_add which sets
the fwnode->dev pointer is skipped. This wasn't previously an issue,
however these two patches:
commit 4731210c09 ("gpiolib: Bind gpio_device to a driver to enable
fw_devlink=on by default")
commit ced2af4195 ("gpiolib: Don't probe gpio_device if it's not the
primary device")
Added some code to the GPIO core which relies on using that
fwnode->dev pointer to determine if a driver is bound to the fwnode
and if not bind a stub GPIO driver. This means the GPIO providers
behind SPI will get both the expected driver and this stub driver
causing the stub driver to fail if it attempts to request any pin
configuration. For example on my system:
madera-pinctrl madera-pinctrl: pin gpio5 already requested by madera-pinctrl; cannot claim for gpiochip3
madera-pinctrl madera-pinctrl: pin-4 (gpiochip3) status -22
madera-pinctrl madera-pinctrl: could not request pin 4 (gpio5) from group aif1 on device madera-pinctrl
gpio_stub_drv gpiochip3: Error applying setting, reverse things back
gpio_stub_drv: probe of gpiochip3 failed with error -22
The firmware node on the device created by the GPIO framework is set
through the of_node pointer hence things generally actually work,
however that fwnode->dev is never set, as the check was skipped at
device_add time. This fix appears to match how the I2C subsystem
handles the same situation.
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20210421101402.8468-1-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
If the setup callback failed, but the controller has auto_runtime_pm
and set_cs, the setup failure could be missed.
Signed-off-by: Joe Burmeister <joe.burmeister@devtank.co.uk>
Link: https://lore.kernel.org/r/20210419130631.4586-1-joe.burmeister@devtank.co.uk
Signed-off-by: Mark Brown <broonie@kernel.org>
When initially probing the SPI slave device, the call for disabling an
SPI device without the SPI_CS_HIGH flag is not applied, as the
condition for checking whether or not the state to be applied equals the
one currently set evaluates to true.
This however might not necessarily be the case, as the chipselect might
be active.
Add a force flag to spi_set_cs which allows to override this
early exit condition. Set it to false everywhere except when called
from spi_setup to sync up the initial CS state.
Fixes commit d40f0b6f2e ("spi: Avoid setting the chip select if we don't
need to")
Signed-off-by: David Bauer <mail@david-bauer.net>
Link: https://lore.kernel.org/r/20210416195956.121811-1-mail@david-bauer.net
Signed-off-by: Mark Brown <broonie@kernel.org>
Use devm_add_action_or_reset() instead of devres_alloc() and
devres_add(), which works the same. This will simplify the
code. There is no functional changes.
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/1617843307-53853-1-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Mark Brown <broonie@kernel.org>
We can't rely on the contents of the devres list during
spi_unregister_controller(), as the list is already torn down at the
time we perform devres_find() for devm_spi_release_controller. This
causes devices registered with devm_spi_alloc_{master,slave}() to be
mistakenly identified as legacy, non-devm managed devices and have their
reference counters decremented below 0.
------------[ cut here ]------------
WARNING: CPU: 1 PID: 660 at lib/refcount.c:28 refcount_warn_saturate+0x108/0x174
[<b0396f04>] (refcount_warn_saturate) from [<b03c56a4>] (kobject_put+0x90/0x98)
[<b03c5614>] (kobject_put) from [<b0447b4c>] (put_device+0x20/0x24)
r4:b6700140
[<b0447b2c>] (put_device) from [<b07515e8>] (devm_spi_release_controller+0x3c/0x40)
[<b07515ac>] (devm_spi_release_controller) from [<b045343c>] (release_nodes+0x84/0xc4)
r5:b6700180 r4:b6700100
[<b04533b8>] (release_nodes) from [<b0454160>] (devres_release_all+0x5c/0x60)
r8:b1638c54 r7:b117ad94 r6:b1638c10 r5:b117ad94 r4:b163dc10
[<b0454104>] (devres_release_all) from [<b044e41c>] (__device_release_driver+0x144/0x1ec)
r5:b117ad94 r4:b163dc10
[<b044e2d8>] (__device_release_driver) from [<b044f70c>] (device_driver_detach+0x84/0xa0)
r9:00000000 r8:00000000 r7:b117ad94 r6:b163dc54 r5:b1638c10 r4:b163dc10
[<b044f688>] (device_driver_detach) from [<b044d274>] (unbind_store+0xe4/0xf8)
Instead, determine the devm allocation state as a flag on the
controller which is guaranteed to be stable during cleanup.
Fixes: 5e844cc37a ("spi: Introduce device-managed SPI controller allocation")
Signed-off-by: William A. Kennington III <wak@google.com>
Link: https://lore.kernel.org/r/20210407095527.2771582-1-wak@google.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Hi,
The older API used to supply additional device properties for the
devices - so mainly the function device_add_properties() - is going to
be removed. The reason why the API will be removed is because it gives
false impression that the properties are assigned directly to the
devices, which has actually never been the case - the properties have
always been assigned to a software fwnode which was then just directly
linked with the device when the old API was used. By only accepting
device properties instead of complete software nodes, the subsystems
remove any change of taking advantage of the other features the
software nodes have.
The change that is required from the spi subsystem and the drivers is
trivial. Basically only the "properties" member in struct
spi_board_info, which was a pointer to struct property_entry, is
replaced with a pointer to a complete software node.
thanks,
Heikki Krogerus (4):
spi: Add support for software nodes
ARM: pxa: icontrol: Constify the software node
ARM: pxa: zeus: Constify the software node
spi: Remove support for dangling device properties
arch/arm/mach-pxa/icontrol.c | 12 ++++++++----
arch/arm/mach-pxa/zeus.c | 6 +++++-
drivers/spi/spi.c | 21 ++++++---------------
include/linux/spi/spi.h | 7 +++----
4 files changed, 22 insertions(+), 24 deletions(-)
--
2.30.1
base-commit: a38fd87484
Making it possible for the drivers to assign complete
software fwnodes to the devices instead of only the device
properties in those nodes.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20210303152814.35070-2-heikki.krogerus@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The 'delay' field in the spi_transfer struct is meant to replace the
'delay_usecs' field. However some cleanup was required to remove the
uses of 'delay_usecs'. Now that it's been cleaned up, we can remove it
from the kernel tree.
Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Link: https://lore.kernel.org/r/20210308145502.1075689-10-aardelean@deviqon.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The main focus of this release from a framework point of view has been
spi-mem where we've acquired support for a few new hardware features
which enable better performance on suitable hardware. Otherwise mostly
thanks to Arnd's cleanup efforts on old platforms we've removed several
obsolete drivers which just about balance out the newer drivers we've
added this cycle.
- Allow drivers to flag if they are unidirectional.
- Support for DTR mode and hardware acceleration of dummy cycles in spi-mem.
- Support for Allwinder H616, Intel Lightning Mountain, nVidia Tegra
QuadSPI, Realtek RTL838x and RTL839x.
- Removal of obsolute EFM32, Txx9 and SIRF Prima and Atlas drivers.
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Merge tag 'spi-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi updates from Mark Brown:
"The main focus of this release from a framework point of view has been
spi-mem where we've acquired support for a few new hardware features
which enable better performance on suitable hardware.
Otherwise mostly thanks to Arnd's cleanup efforts on old platforms
we've removed several obsolete drivers which just about balance out
the newer drivers we've added this cycle.
Summary:
- Allow drivers to flag if they are unidirectional.
- Support for DTR mode and hardware acceleration of dummy cycles in
spi-mem.
- Support for Allwinder H616, Intel Lightning Mountain, nVidia Tegra
QuadSPI, Realtek RTL838x and RTL839x.
- Removal of obsolete EFM32, Txx9 and SIRF Prima and Atlas drivers"
* tag 'spi-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (76 commits)
spi: Skip zero-length transfers in spi_transfer_one_message()
spi: dw: Avoid stack content exposure
spi: cadence-quadspi: Use spi_mem_dtr_supports_op()
spi: spi-mem: add spi_mem_dtr_supports_op()
spi: atmel-quadspi: Disable the QSPI IP at suspend()
spi: pxa2xx: Add IDs for the controllers found on Intel Lynxpoint
spi: pxa2xx: Fix the controller numbering for Wildcat Point
spi: Change provied to provided in the file spi.h
spi: mediatek: add set_cs_timing support
spi: support CS timing for HW & SW mode
spi: add power control when set_cs_timing
spi: stm32: make spurious and overrun interrupts visible
spi: stm32h7: replace private SPI_1HZ_NS with NSEC_PER_SEC
spi: stm32: defer probe for reset
spi: stm32: driver uses reset controller only at init
spi: stm32h7: ensure message are smaller than max size
spi: stm32: use bitfield macros
spi: stm32: do not mandate cs_gpio
spi: stm32: properly handle 0 byte transfer
spi: clps711xx: remove redundant white-space
...
With the introduction of 26751de25d ("spi: bcm2835: Micro-optimise
FIFO loops") it has become apparent that some users might initiate
zero-length SPI transfers. A fact the micro-optimization omitted, and
which turned out to cause crashes[1].
Instead of changing the micro-optimization itself, use a bigger hammer
and skip zero-length transfers altogether for drivers using the default
transfer_one_message() implementation.
Reported-by: Phil Elwell <phil@raspberrypi.com>
Fixes: 26751de25d ("spi: bcm2835: Micro-optimise FIFO loops")
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
[1] https://github.com/raspberrypi/linux/issues/4100
Link: https://lore.kernel.org/r/20210211180820.25757-1-nsaenzjulienne@suse.de
Signed-off-by: Mark Brown <broonie@kernel.org>
David Jander