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path: root/drivers/spi/spi.c
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2019-10-31spi: add power control when set_csLuhua Xu
As to set_cs takes effect immediately, power spi is needed when setup spi. Cc: Mark Brown <broonie@kernel.org> Signed-off-by: Luhua Xu <luhua.xu@mediatek.com> Link: https://lore.kernel.org/r/1572426234-30019-1-git-send-email-luhua.xu@mediatek.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-25spi: Fix NULL pointer when setting SPI_CS_HIGH for GPIO CSGregory CLEMENT
Even if the flag use_gpio_descriptors is set, it is possible that cs_gpiods was not allocated, which leads to a kernel crash. Reported-by: "kernelci.org bot" <bot@kernelci.org> Fixes: 3e5ec1db8bfe ("spi: Fix SPI_CS_HIGH setting when using native and GPIO CS") Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Link: https://lore.kernel.org/r/20191024141309.22434-1-gregory.clement@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org> Cc: <stable@vger.kernel.org>
2019-10-23spi: Fix spelling in the commentsAndy Shevchenko
Two spelling mistakes are being fixed. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20191023121643.25237-1-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-18Merge tag 'v5.4-rc3' into spi-5.4Mark Brown
Linux 5.4-rc3
2019-10-18spi: Fix SPI_CS_HIGH setting when using native and GPIO CSGregory CLEMENT
When improving the CS GPIO support at core level, the SPI_CS_HIGH has been enabled for all the CS lines used for a given SPI controller. However, the SPI framework allows to have on the same controller native CS and GPIO CS. The native CS may not support the SPI_CS_HIGH, so they should not be setup automatically. With this patch the setting is done only for the CS that will use a GPIO as CS Fixes: f3186dd87669 ("spi: Optionally use GPIO descriptors for CS GPIOs") Cc: <stable@vger.kernel.org> Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Link: https://lore.kernel.org/r/20191018152929.3287-1-gregory.clement@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-15spi: spi-fsl-espi: convert transfer delay to `spi_delay` formatAlexandru Ardelean
The way the max delay is computed for this controller, it looks like it is searching for the max delay from an SPI message a using that. No idea if this is valid. But this change should support both `delay_usecs` and the new `delay` data which is of `spi_delay` type. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-17-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-15spi: implement SW control for CS timesAlexandru Ardelean
This change implements CS control for setup, hold & inactive delays. The `cs_setup` delay is completely new, and can help with cases where asserting the CS, also brings the device out of power-sleep, where there needs to be a longer (than usual), before transferring data. The `cs_hold` time can overlap with the `delay` (or `delay_usecs`) from an SPI transfer. The main difference is that `cs_hold` implies that CS will be de-asserted. The `cs_inactive` delay does not have a clear use-case yet. It has been implemented mostly because the `spi_set_cs_timing()` function implements it. To some degree, this could overlap or replace `cs_change_delay`, but this will require more consideration/investigation in the future. All these delays have been added to the `spi_controller` struct, as they would typically be configured by calling `spi_set_cs_timing()` after an `spi_setup()` call. Software-mode for CS control, implies that the `set_cs_timing()` hook has not been provided for the `spi_controller` object. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-16-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-15spi: tegra114: change format for `spi_set_cs_timing()` functionAlexandru Ardelean
The initial version of `spi_set_cs_timing()` was implemented with consideration only for clock-cycles as delay. For cases like `CS setup` time, it's sometimes needed that micro-seconds (or nano-seconds) are required, or sometimes even longer delays, for cases where the device needs a little longer to start transferring that after CS is asserted. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-15-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-15spi: introduce `delay` field for `spi_transfer` + spi_transfer_delay_exec()Alexandru Ardelean
The change introduces the `delay` field to the `spi_transfer` struct as an `struct spi_delay` type. This intends to eventually replace `delay_usecs`. But, since there are many users of `delay_usecs`, this needs some intermediate work. A helper called `spi_transfer_delay_exec()` is also added, which maintains backwards compatibility with `delay_usecs`, by assigning the value to `delay` if non-zero. This should maintain backwards compatibility with current users of `udelay_usecs`. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-9-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-15spi: core,atmel: convert `word_delay_usecs` -> `word_delay` for spi_deviceAlexandru Ardelean
This change does a conversion from the `word_delay_usecs` -> `word_delay` for the `spi_device` struct. This allows users to specify inter-word delays in other unit types (nano-seconds or clock cycles), depending on how users want. The Atmel SPI driver is the only current user of the `word_delay_usecs` field (from the `spi_device` struct). So, it needed a slight conversion to use the `word_delay` as an `spi_delay` struct. In SPI core, the only required mechanism is to update the `word_delay` information per `spi_transfer`. This requires a bit more logic than before, because it needs that both delays be converted to a common unit (nano-seconds) for comparison. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-8-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-15spi: make `cs_change_delay` the first user of the `spi_delay` logicAlexandru Ardelean
Since the logic for `spi_delay` struct + `spi_delay_exec()` has been copied from the `cs_change_delay` logic, it's natural to make this delay, the first user. The `cs_change_delay` logic requires that the default remain 10 uS, in case it is unspecified/unconfigured. So, there is some special handling needed to do that. The ADIS library is one of the few users of the new `cs_change_delay` parameter for an spi_transfer. The introduction of the `spi_delay` struct, requires that the users of of `cs_change_delay` get an update. This change also updates the ADIS library. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-4-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-15spi: introduce spi_delay struct as "value + unit" & spi_delay_exec()Alexandru Ardelean
There are plenty of delays that have been introduced in SPI core. Most of them are in micro-seconds, some need to be in nano-seconds, and some in clock-cycles. For some of these delays (related to transfers & CS timing) it may make sense to have a `spi_delay` struct that abstracts these a bit. The important element of these delays [for unification] seems to be the `unit` of the delay. It looks like micro-seconds is good enough for most people, but every-once in a while, some delays seem to require other units of measurement. This change adds the `spi_delay` struct & a `spi_delay_exec()` function that processes a `spi_delay` object/struct to execute the delay. It's a copy of the `cs_change_delay` mechanism, but without the default for 10 uS. The clock-cycle delay unit is a bit special, as it needs to be bound to an `spi_transfer` object to execute. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-3-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-15spi: move `cs_change_delay` backwards compat logic outside switchAlexandru Ardelean
The `cs_change_delay` backwards compatibility value could be moved outside of the switch statement. The only reason to do it, is to make the next patches easier to diff. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-2-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-07spi: Add a PTP system timestamp to the transfer structureVladimir Oltean
SPI is one of the interfaces used to access devices which have a POSIX clock driver (real time clocks, 1588 timers etc). The fact that the SPI bus is slow is not what the main problem is, but rather the fact that drivers don't take a constant amount of time in transferring data over SPI. When there is a high delay in the readout of time, there will be uncertainty in the value that has been read out of the peripheral. When that delay is constant, the uncertainty can at least be approximated with a certain accuracy which is fine more often than not. Timing jitter occurs all over in the kernel code, and is mainly caused by having to let go of the CPU for various reasons such as preemption, servicing interrupts, going to sleep, etc. Another major reason is CPU dynamic frequency scaling. It turns out that the problem of retrieving time from a SPI peripheral with high accuracy can be solved by the use of "PTP system timestamping" - a mechanism to correlate the time when the device has snapshotted its internal time counter with the Linux system time at that same moment. This is sufficient for having a precise time measurement - it is not necessary for the whole SPI transfer to be transmitted "as fast as possible", or "as low-jitter as possible". The system has to be low-jitter for a very short amount of time to be effective. This patch introduces a PTP system timestamping mechanism in struct spi_transfer. This is to be used by SPI device drivers when they need to know the exact time at which the underlying device's time was snapshotted. More often than not, SPI peripherals have a very exact timing for when their SPI-to-interconnect bridge issues a transaction for snapshotting and reading the time register, and that will be dependent on when the SPI-to-interconnect bridge figures out that this is what it should do, aka as soon as it sees byte N of the SPI transfer. Since spi_device drivers are the ones who'd know best how the peripheral behaves in this regard, expose a mechanism in spi_transfer which allows them to specify which word (or word range) from the transfer should be timestamped. Add a default implementation of the PTP system timestamping in the SPI core. This is not going to be satisfactory performance-wise, but should at least increase the likelihood that SPI device drivers will use PTP system timestamping in the future. There are 3 entry points from the core towards the SPI controller drivers: - transfer_one: The driver is passed individual spi_transfers to execute. This is the easiest to timestamp. - transfer_one_message: The core passes the driver an entire spi_message (a potential batch of spi_transfers). The core puts the same pre and post timestamp to all transfers within a message. This is not ideal, but nothing better can be done by default anyway, since the core has no insight into how the driver batches the transfers. - transfer: Like transfer_one_message, but for unqueued drivers (i.e. the driver implements its own queue scheduling). Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Link: https://lore.kernel.org/r/20190905010114.26718-3-olteanv@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-17Merge tag 'leds-for-5.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds Pull LED updates from Jacek Anaszewski: "In this cycle we've finally managed to contribute the patch set sorting out LED naming issues. Besides that there are many changes scattered among various LED class drivers and triggers. LED naming related improvements: - add new 'function' and 'color' fwnode properties and deprecate 'label' property which has been frequently abused for conveying vendor specific names that have been available in sysfs anyway - introduce a set of standard LED_FUNCTION* definitions - introduce a set of standard LED_COLOR_ID* definitions - add a new {devm_}led_classdev_register_ext() API with the capability of automatic LED name composition basing on the properties available in the passed fwnode; the function is backwards compatible in a sense that it uses 'label' data, if present in the fwnode, for creating LED name - add tools/leds/get_led_device_info.sh script for retrieving LED vendor, product and bus names, if applicable; it also performs basic validation of an LED name - update following drivers and their DT bindings to use the new LED registration API: - leds-an30259a, leds-gpio, leds-as3645a, leds-aat1290, leds-cr0014114, leds-lm3601x, leds-lm3692x, leds-lp8860, leds-lt3593, leds-sc27xx-blt Other LED class improvements: - replace {devm_}led_classdev_register() macros with inlines - allow to call led_classdev_unregister() unconditionally - switch to use fwnode instead of be stuck with OF one LED triggers improvements: - led-triggers: - fix dereferencing of null pointer - fix a memory leak bug - ledtrig-gpio: - GPIO 0 is valid Drop superseeded apu2/3 support from leds-apu since for apu2+ a newer, more complete driver exists, based on a generic driver for the AMD SOCs gpio-controller, supporting LEDs as well other devices: - drop profile field from priv data - drop iosize field from priv data - drop enum_apu_led_platform_types - drop superseeded apu2/3 led support - add pr_fmt prefix for better log output - fix error message on probing failure Other misc fixes and improvements to existing LED class drivers: - leds-ns2, leds-max77650: - add of_node_put() before return - leds-pwm, leds-is31fl32xx: - use struct_size() helper - leds-lm3697, leds-lm36274, leds-lm3532: - switch to use fwnode_property_count_uXX() - leds-lm3532: - fix brightness control for i2c mode - change the define for the fs current register - fixes for the driver for stability - add full scale current configuration - dt: Add property for full scale current. - avoid potentially unpaired regulator calls - move static keyword to the front of declarations - fix optional led-max-microamp prop error handling - leds-max77650: - add of_node_put() before return - add MODULE_ALIAS() - Switch to fwnode property API - leds-as3645a: - fix misuse of strlcpy - leds-netxbig: - add of_node_put() in netxbig_leds_get_of_pdata() - remove legacy board-file support - leds-is31fl319x: - simplify getting the adapter of a client - leds-ti-lmu-common: - fix coccinelle issue - move static keyword to the front of declaration - leds-syscon: - use resource managed variant of device register - leds-ktd2692: - fix a typo in the name of a constant - leds-lp5562: - allow firmware files up to the maximum length - leds-an30259a: - fix typo - leds-pca953x: - include the right header" * tag 'leds-for-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds: (72 commits) leds: lm3532: Fix optional led-max-microamp prop error handling led: triggers: Fix dereferencing of null pointer leds: ti-lmu-common: Move static keyword to the front of declaration leds: lm3532: Move static keyword to the front of declarations leds: trigger: gpio: GPIO 0 is valid leds: pwm: Use struct_size() helper leds: is31fl32xx: Use struct_size() helper leds: ti-lmu-common: Fix coccinelle issue in TI LMU leds: lm3532: Avoid potentially unpaired regulator calls leds: syscon: Use resource managed variant of device register leds: Replace {devm_}led_classdev_register() macros with inlines leds: Allow to call led_classdev_unregister() unconditionally leds: lm3532: Add full scale current configuration dt: lm3532: Add property for full scale current. leds: lm3532: Fixes for the driver for stability leds: lm3532: Change the define for the fs current register leds: lm3532: Fix brightness control for i2c mode leds: Switch to use fwnode instead of be stuck with OF one leds: max77650: Switch to fwnode property API led: triggers: Fix a memory leak bug ...
2019-09-11spi: Guarantee cacheline alignment of driver-private dataLukas Wunner
__spi_alloc_controller() uses a single allocation to accommodate struct spi_controller and the driver-private data, but places the latter behind the former. This order does not guarantee cacheline alignment of the driver-private data. (It does guarantee cacheline alignment of struct spi_controller but the structure doesn't make any use of that property.) Round up struct spi_controller to cacheline size. A forthcoming commit leverages this to grant DMA access to driver-private data of the BCM2835 SPI master. An alternative, less economical approach would be to use two allocations. A third approach consists of reversing the order to conserve memory. But Mark Brown is concerned that it may result in a performance penalty on architectures that don't like unaligned accesses. Signed-off-by: Lukas Wunner <lukas@wunner.de> Link: https://lore.kernel.org/r/01625b9b26b93417fb09d2c15ad02dfe9cdbbbe5.1568187525.git.lukas@wunner.de Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-05spi: Use an abbreviated pointer to ctlr->cur_msg in __spi_pump_messagesVladimir Oltean
This helps a bit with line fitting now (the list_first_entry call) as well as during the next patch which needs to iterate through all transfers of ctlr->cur_msg so it timestamps them. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Link: https://lore.kernel.org/r/20190905010114.26718-2-olteanv@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-08-08spi: Rename of_spi_register_master() functionLinus Walleij
Rename this function to of_spi_get_gpio_numbers() as this is what the function does, it does not register a master, it is called in the path of registering a master so the name is logical in a convoluted way, but it is better to follow Rusty Russell's ABI level no 7: "The obvious use is (probably) the correct one" Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20190808150321.23319-1-linus.walleij@linaro.org Signed-off-by: Mark Brown <broonie@kernel.org>
2019-08-02spi: Reduce kthread priorityPeter Zijlstra
The SPI thingies request FIFO-99 by default, reduce this to FIFO-50. FIFO-99 is the very highest priority available to SCHED_FIFO and it not a suitable default; it would indicate the SPI work is the most important work on the machine. Cc: Benson Leung <bleung@chromium.org> Cc: Enric Balletbo i Serra <enric.balletbo@collabora.com> Cc: Guenter Roeck <groeck@chromium.org> Cc: Mark Brown <broonie@kernel.org> Cc: linux-spi@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20190801111541.917256884@infradead.org Signed-off-by: Mark Brown <broonie@kernel.org>
2019-08-01spi: core: Use DEVICE_ATTR_RW() for SPI slave control sysfs attributeGeert Uytterhoeven
Convert the SPI slave control sysfs attribute from DEVICE_ATTR() to DEVICE_ATTR_RW(), to reduce boilerplate. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20190731124738.14519-1-geert+renesas@glider.be Signed-off-by: Mark Brown <broonie@kernel.org>
2019-07-30drivers: Introduce device lookup variants by ACPI_COMPANION deviceSuzuki K Poulose
Add a generic helper to match a device by the ACPI_COMPANION device and provide wrappers for the device lookup APIs. Cc: Len Brown <lenb@kernel.org> Cc: linux-acpi@vger.kernel.org Cc: linux-spi@vger.kernel.org Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: linux-i2c@vger.kernel.org Cc: "Rafael J. Wysocki" <rafael@kernel.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Wolfram Sang <wsa@the-dreams.de> # I2C parts Link: https://lore.kernel.org/r/20190723221838.12024-6-suzuki.poulose@arm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-30drivers: Introduce device lookup variants by of_nodeSuzuki K Poulose
Introduce wrappers for {bus/driver/class}_find_device() to locate devices by its of_node. Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <maxime.ripard@bootlin.com> Cc: dri-devel@lists.freedesktop.org Cc: David Airlie <airlied@linux.ie> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: devicetree@vger.kernel.org Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Frank Rowand <frowand.list@gmail.com> Cc: Heiko Stuebner <heiko@sntech.de> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: linux-i2c@vger.kernel.org Cc: linux-rockchip@lists.infradead.org Cc: linux-spi@vger.kernel.org Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Cc: Takashi Iwai <tiwai@suse.com> Cc: Alan Tull <atull@kernel.org> Cc: linux-fpga@vger.kernel.org Cc: Peter Rosin <peda@axentia.se> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Heiner Kallweit <hkallweit1@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Thor Thayer <thor.thayer@linux.intel.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Peter Rosin <peda@axentia.se> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Acked-by: Lee Jones <lee.jones@linaro.org> Acked-by: Wolfram Sang <wsa@the-dreams.de> # I2C part Acked-by: Moritz Fischer <mdf@kernel.org> # For FPGA part Acked-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20190723221838.12024-3-suzuki.poulose@arm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-12Merge tag 'driver-core-5.3-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core and debugfs updates from Greg KH: "Here is the "big" driver core and debugfs changes for 5.3-rc1 It's a lot of different patches, all across the tree due to some api changes and lots of debugfs cleanups. Other than the debugfs cleanups, in this set of changes we have: - bus iteration function cleanups - scripts/get_abi.pl tool to display and parse Documentation/ABI entries in a simple way - cleanups to Documenatation/ABI/ entries to make them parse easier due to typos and other minor things - default_attrs use for some ktype users - driver model documentation file conversions to .rst - compressed firmware file loading - deferred probe fixes All of these have been in linux-next for a while, with a bunch of merge issues that Stephen has been patient with me for" * tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits) debugfs: make error message a bit more verbose orangefs: fix build warning from debugfs cleanup patch ubifs: fix build warning after debugfs cleanup patch driver: core: Allow subsystems to continue deferring probe drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT arch_topology: Remove error messages on out-of-memory conditions lib: notifier-error-inject: no need to check return value of debugfs_create functions swiotlb: no need to check return value of debugfs_create functions ceph: no need to check return value of debugfs_create functions sunrpc: no need to check return value of debugfs_create functions ubifs: no need to check return value of debugfs_create functions orangefs: no need to check return value of debugfs_create functions nfsd: no need to check return value of debugfs_create functions lib: 842: no need to check return value of debugfs_create functions debugfs: provide pr_fmt() macro debugfs: log errors when something goes wrong drivers: s390/cio: Fix compilation warning about const qualifiers drivers: Add generic helper to match by of_node driver_find_device: Unify the match function with class_find_device() bus_find_device: Unify the match callback with class_find_device ...
2019-07-04Merge remote-tracking branch 'spi/topic/pump-rt' into spi-nextMark Brown
2019-06-24spi/acpi: avoid spurious matches during slave enumerationArd Biesheuvel
In the new SPI ACPI slave enumeration code, we use the value of lookup.max_speed_khz as a flag to decide whether a match occurred. However, doing so only makes sense if we initialize its value to zero beforehand, or otherwise, random junk from the stack will cause spurious matches. So zero initialize the lookup struct fully, and only set the non-zero members explicitly. Fixes: 4c3c59544f33 ("spi/acpi: enumerate all SPI slaves in the namespace") Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: andy.shevchenko@gmail.com Cc: masahisa.kojima@linaro.org Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Jarkko Nikula <jarkko.nikula@linux.intel.com> Cc: linux-acpi@vger.kernel.org Cc: Lukas Wunner <lukas@wunner.de> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-06-24bus_find_device: Unify the match callback with class_find_deviceSuzuki K Poulose
There is an arbitrary difference between the prototypes of bus_find_device() and class_find_device() preventing their callers from passing the same pair of data and match() arguments to both of them, which is the const qualifier used in the prototype of class_find_device(). If that qualifier is also used in the bus_find_device() prototype, it will be possible to pass the same match() callback function to both bus_find_device() and class_find_device(), which will allow some optimizations to be made in order to avoid code duplication going forward. Also with that, constify the "data" parameter as it is passed as a const to the match function. For this reason, change the prototype of bus_find_device() to match the prototype of class_find_device() and adjust its callers to use the const qualifier in accordance with the new prototype of it. Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Andreas Noever <andreas.noever@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Corey Minyard <minyard@acm.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Kershner <david.kershner@unisys.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: David Airlie <airlied@linux.ie> Cc: Felipe Balbi <balbi@kernel.org> Cc: Frank Rowand <frowand.list@gmail.com> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Cc: Harald Freudenberger <freude@linux.ibm.com> Cc: Hartmut Knaack <knaack.h@gmx.de> Cc: Heiko Stuebner <heiko@sntech.de> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jonathan Cameron <jic23@kernel.org> Cc: "James E.J. Bottomley" <jejb@linux.ibm.com> Cc: Len Brown <lenb@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michael Jamet <michael.jamet@intel.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Peter Oberparleiter <oberpar@linux.ibm.com> Cc: Sebastian Ott <sebott@linux.ibm.com> Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Cc: Yehezkel Bernat <YehezkelShB@gmail.com> Cc: rafael@kernel.org Acked-by: Corey Minyard <minyard@acm.org> Acked-by: David Kershner <david.kershner@unisys.com> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Acked-by: Wolfram Sang <wsa@the-dreams.de> # for the I2C parts Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-20spi: fix ctrl->num_chipselect constraintTudor Ambarus
at91sam9g25ek showed the following error at probe: atmel_spi f0000000.spi: Using dma0chan2 (tx) and dma0chan3 (rx) for DMA transfers atmel_spi: probe of f0000000.spi failed with error -22 Commit 0a919ae49223 ("spi: Don't call spi_get_gpio_descs() before device name is set") moved the calling of spi_get_gpio_descs() after ctrl->dev is set, but didn't move the !ctrl->num_chipselect check. When there are chip selects in the device tree, the spi-atmel driver lets the SPI core discover them when registering the SPI master. The ctrl->num_chipselect is thus expected to be set by spi_get_gpio_descs(). Move the !ctlr->num_chipselect after spi_get_gpio_descs() as it was before the aforementioned commit. While touching this block, get rid of the explicit comparison with 0 and update the commenting style. Fixes: 0a919ae49223 ("spi: Don't call spi_get_gpio_descs() before device name is set") Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-06-19spi/acpi: fix incorrect ACPI parent checkArd Biesheuvel
The ACPI device object parsing code for SPI slaves enumerates the entire ACPI namespace to look for devices that refer to the master in question via the 'resource_source' field in the 'SPISerialBus' resource. If that field does not refer to a valid ACPI device or if it refers to the wrong SPI master, we should disregard the device. Current, the valid device check is wrong, since it gets the polarity of 'status' wrong. This could cause issues if the 'resource_source' field is bogus but parent_handle happens to refer to the correct master (which is not entirely imaginary since this code runs in a loop) So test for ACPI_FAILURE() instead, to make the code more self explanatory. Fixes: 4c3c59544f33 ("spi/acpi: enumerate all SPI slaves in the namespace") Reported-by: kbuild test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: andy.shevchenko@gmail.com Cc: masahisa.kojima@linaro.org Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Jarkko Nikula <jarkko.nikula@linux.intel.com> Cc: linux-acpi@vger.kernel.org Cc: Lukas Wunner <lukas@wunner.de> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-06-18spi: don't open code list_for_each_entry_safe_reverse()Vladimir Zapolskiy
The loop declaration in function spi_res_release() can be simplified by reusing the common list_for_each_entry_safe_reverse() helper macro. Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-06-17spi: No need to assign dummy value in spi_unregister_controller()Andy Shevchenko
The device_for_each_child() doesn't require the returned value to be checked. Thus, drop the dummy variable completely and have no warning anymore: drivers/spi/spi.c: In function ‘spi_unregister_controller’: drivers/spi/spi.c:2480:6: warning: variable ‘dummy’ set but not used [-Wunused-but-set-variable] int dummy; ^~~~~ Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-06-13spi/acpi: enumerate all SPI slaves in the namespaceArd Biesheuvel
Currently, the ACPI enumeration that takes place when registering a SPI master only considers immediate child devices in the ACPI namespace, rather than checking the ResourceSource field in the SpiSerialBus() resource descriptor. This is incorrect: SPI slaves could reside anywhere in the ACPI namespace, and so we should enumerate the entire namespace and look for any device that refers to the newly registered SPI master in its resource descriptor. So refactor the existing code and use a lookup structure so that allocating the SPI device structure is deferred until we have identified the device as an actual child of the controller. This approach is loosely based on the way the I2C subsystem handles ACPI enumeration. Note that Apple x86 hardware does not rely on SpiSerialBus() resources in _CRS but uses nested devices below the controller's device node in the ACPI namespace, with a special set of device properties. This means we have to take care to only parse those properties for device nodes that are direct children of the controller node. Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: linux-spi@vger.kernel.org Cc: broonie@kernel.org Cc: andy.shevchenko@gmail.com Cc: masahisa.kojima@linaro.org Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Jarkko Nikula <jarkko.nikula@linux.intel.com> Cc: linux-acpi@vger.kernel.org Cc: Lukas Wunner <lukas@wunner.de> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-06-10spi: Use struct_size() helperGustavo A. R. Silva
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct spi_replaced_transfers { ... struct spi_transfer inserted_transfers[]; }; Make use of the struct_size() helper instead of an open-coded version in order to avoid any potential type mistakes. So, replace the following form: insert * sizeof(struct spi_transfer) + sizeof(struct spi_replaced_transfers) with: struct_size(rxfer, inserted_transfers, insert) This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-23Merge branch 'spi-5.2' into spi-5.3Mark Brown
2019-05-23spi: Allow SPI devices to request the pumping thread be realtimeDouglas Anderson
Right now the only way to get the SPI pumping thread bumped up to realtime priority is for the controller to request it. However it may be that the controller works fine with the normal priority but communication to a particular SPI device on the bus needs realtime priority. Let's add a way for devices to request realtime priority when they set themselves up. NOTE: this will just affect the priority of transfers that end up on the SPI core's pumping thread. In many cases transfers happen in the context of the caller so if you need realtime priority for all transfers you should ensure the calling context is also realtime priority. Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Guenter Roeck <groeck@chromium.org> Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-23spi: abort spi_sync if failed to prepare_transfer_hardwareSuper Liu
There is no chance to wait spi message complete if failed to prepare_transfer_hardware(). Therefore, finalize this message and abort transfer with corresponding return status to release this block case. Logs: [17400.283005] c7 3267 PM: PM: suspend entry 2019-05-04 03:01:14.403097147 UTC [17400.283013] c7 3267 PM: suspend entry (deep) [17400.283016] c6 3267 PM: Syncing filesystems ... done. [17400.584395] c1 753 spi_geni 890000.spi: spi_geni_prepare_transfer_hardware:Error enabling SE resources -13 [17400.584404] c1 753 spi_master spi1: failed to prepare transfer hardware [17400.664611] c4 3267 PM: PM: suspend exit 2019-05-04 03:01:15.235273018 UTC Flow: __spi_sync@spi.c | if (status == 0) { | /* Push out the messages in the calling context if we | * can. | */ | if (ctlr->transfer == spi_queued_transfer) { | SPI_STATISTICS_INCREMENT_FIELD(&ctlr->statistics, | spi_sync_immediate); | SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, | spi_sync_immediate); | __spi_pump_messages(ctlr, false); | } | | wait_for_completion(&done); <== stuck here!!! | status = message->status; | } | message->context = NULL; | return status; | --> __spi_pump_messages@spi.c | if (!was_busy && ctlr->prepare_transfer_hardware) { | ret = ctlr->prepare_transfer_hardware(ctlr); | if (ret) { | dev_err(&ctlr->dev, | "failed to prepare transfer hardware\n"); | | if (ctlr->auto_runtime_pm) | pm_runtime_put(ctlr->dev.parent); | mutex_unlock(&ctlr->io_mutex); | return; | } | } | --> spi_geni_prepare_transfer_hardware@spi-geni-qcom.c | ret = pm_runtime_get_sync(mas->dev); | if (ret < 0) { | dev_err(mas->dev, | "%s:Error enabling SE resources %d\n", | __func__, ret); | pm_runtime_put_noidle(mas->dev); | goto exit_prepare_transfer_hardware; Signed-off-by: Super Liu <supercjliu@google.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-13spi: core: allow reporting the effectivly used speed_hz for a transferMartin Sperl
Provide a means for the spi bus driver to report the effectively used spi clock frequency used for each spi_transfer. Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-09spi: Fix Raspberry Pi breakageMark Brown
This reverts commit c9ba7a16d0f1 (Release spi_res after finalizing message) which causes races during cleanup. Reported-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-08spi: core: allow defining time that cs is deasserted as a multiple of SCKMartin Sperl
Support setting a delay between cs assert and deassert as a multiple of spi clock length. Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-08spi: core: allow defining time that cs is deassertedMartin Sperl
For some SPI devices that support speed_hz > 1MHz the default 10 us delay when cs_change = 1 is typically way to long and may result in poor spi bus utilization. This patch makes it possible to control the delay at micro or nano second resolution on a per spi_transfer basis. It even allows an "as fast as possible" mode with: xfer.cs_change_delay_unit = SPI_DELAY_UNIT_NSECS; xfer.cs_change_delay = 0; The delay code is shared between delay_usecs and cs_change_delay for consistency and reuse, so in the future this change_delay_unit could also apply to delay_usec as well. Note that on slower SOCs/CPU actually reaching ns deasserts on cs is not realistic as the gpio overhead alone (without any delays added ) may already leave cs deasserted for more than 1us - at least on a raspberry pi. But at the very least this way we can keep it as short as possible. Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-02spi: Clear SPI_CS_HIGH flag from bad_bits for GPIO chip-selectSerge Semin
When GPIO chip-select is used nothing prevents any available SPI controllers to work with both CS-high and traditional CS-low modes. In fact the SPI bus core code already does it, so we don't need to introduce any modification there. But spi_setup() still fails to switch the interface settings if CS-high flag is set for the case of GPIO-driven slave chip-select when the SPI controller doesn't support the hardwired CS-inversion. Lets fix it by clearing the SPI_CS_HIGH flag out from bad_bits (unsupported by controller) when client chip is selected by GPIO. This feature is useful for slave devices, which in accordance with communication protocol can work with both active-high and active-low chip-selects. I am aware of one such device. It is MMC-SPI interface, when at init sequence the driver needs to perform a read operation with low and high chip-select sequentially (requirement of 74 clock cycles with both chipselect, see the mmc_spi driver for details). Signed-off-by: Serge Semin <fancer.lancer@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-02spi: Release spi_res after finalizing messageNoralf Trønnes
spi_split_transfers_maxsize() can be used to split a transfer. This function uses spi_res to lifetime manage the added transfer structures. So in order to finalize the current message while it contains the split transfers, spi_res_release() must be called after finalizing. Signed-off-by: Noralf Trønnes <noralf@tronnes.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-02spi: Remove warning in spi_split_transfers_maxsize()Noralf Trønnes
Don't warn about splitting transfers, the info is available in the statistics if needed. Signed-off-by: Noralf Trønnes <noralf@tronnes.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-02spi: Remove one needless transfer speed fall back caseJarkko Nikula
Falling back to maximum speed of the controller in case of SPI slave maximum speed is not set is needless. It already defaults to maximum speed of the controller since commit 052eb2d49006 ("spi: core: Set max_speed_hz of spi_device default to max_speed_hz of controller"). Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-04-08spi: add a method for configuring CS timingSowjanya Komatineni
This patch creates set_cs_timing SPI master optional method for SPI masters to implement configuring CS timing if applicable. This patch also creates spi_cs_timing accessory for SPI clients to use for requesting SPI master controllers to configure device requested CS setup time, hold time and inactive delay. Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-04-08spi: kill useless initializer in spi_register_controller()Sergei Shtylyov
The 'status' local variable is initialized but this value is never used, thus kill that initializer. Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-04-05spi: Don't call spi_get_gpio_descs() before device name is setAndrey Smirnov
Move code calling spi_get_gpio_descs() to happen after ctlr->dev's name is set in order to have proper GPIO consumer names. Before: cat /sys/kernel/debug/gpio gpiochip0: GPIOs 0-31, parent: platform/40049000.gpio, vf610-gpio: gpio-6 ( |regulator-usb0-vbus ) out lo gpiochip1: GPIOs 32-63, parent: platform/4004a000.gpio, vf610-gpio: gpio-36 ( |scl ) in hi gpio-37 ( |sda ) in hi gpio-40 ( |(null) CS1 ) out lo gpio-41 ( |(null) CS0 ) out lo ACTIVE LOW gpio-42 ( |miso ) in hi gpio-43 ( |mosi ) in lo gpio-44 ( |sck ) out lo After: cat /sys/kernel/debug/gpio gpiochip0: GPIOs 0-31, parent: platform/40049000.gpio, vf610-gpio: gpio-6 ( |regulator-usb0-vbus ) out lo gpiochip1: GPIOs 32-63, parent: platform/4004a000.gpio, vf610-gpio: gpio-36 ( |scl ) in hi gpio-37 ( |sda ) in hi gpio-40 ( |spi0 CS1 ) out lo gpio-41 ( |spi0 CS0 ) out lo ACTIVE LOW gpio-42 ( |miso ) in hi gpio-43 ( |mosi ) in lo gpio-44 ( |sck ) out lo Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com> Cc: Mark Brown <broonie@kernel.org> Cc: Chris Healy <cphealy@gmail.com> Cc: linux-spi@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Mark Brown <broonie@kernel.org>
2019-04-05Merge branch 'spi-5.1' into spi-5.2Mark Brown
2019-04-04spi: Add missing error handling for CS GPIOsGeert Uytterhoeven
While devm_gpiod_get_index_optional() returns NULL if the GPIO is not present (i.e. -ENOENT), it may still return other error codes, like -EPROBE_DEFER. Currently these are not handled, leading to unrecoverable failures later in case of probe deferral: gpiod_set_consumer_name: invalid GPIO (errorpointer) gpiod_direction_output: invalid GPIO (errorpointer) gpiod_set_value_cansleep: invalid GPIO (errorpointer) gpiod_set_value_cansleep: invalid GPIO (errorpointer) gpiod_set_value_cansleep: invalid GPIO (errorpointer) Detect and propagate errors to fix this. Fixes: f3186dd876697e69 ("spi: Optionally use GPIO descriptors for CS GPIOs") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-03-21spi: export tracepoint symbols to modulesArnd Bergmann
The newly added tracepoints in the spi-mxs driver cause a link error when the driver is a loadable module: ERROR: "__tracepoint_spi_transfer_stop" [drivers/spi/spi-mxs.ko] undefined! ERROR: "__tracepoint_spi_transfer_start" [drivers/spi/spi-mxs.ko] undefined! I'm not quite sure where to put the export statements, but directly after the inclusion of the header seems as good as any other place. Fixes: f3fdea3af405 ("spi: mxs: add tracing to custom .transfer_one_message callback") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-03-11spi: Fix zero length xfer bugChris Lesiak
This fixes a bug for messages containing both zero length and unidirectional xfers. The function spi_map_msg will allocate dummy tx and/or rx buffers for use with unidirectional transfers when the hardware can only do a bidirectional transfer. That dummy buffer will be used in place of a NULL buffer even when the xfer length is 0. Then in the function __spi_map_msg, if he hardware can dma, the zero length xfer will have spi_map_buf called on the dummy buffer. Eventually, __sg_alloc_table is called and returns -EINVAL because nents == 0. This fix prevents the error by not using the dummy buffer when the xfer length is zero. Signed-off-by: Chris Lesiak <chris.lesiak@licor.com> Signed-off-by: Mark Brown <broonie@kernel.org>