kernel/linux.git/include/linux/spi, branch v5.10.257

spi: Fix deadlock when adding SPI controllers on SPI buses

2024-11-17T13:59:37+00:00

commit 6098475d4cb48d821bdf453c61118c56e26294f0 upstream. 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 Signed-off-by: Mark Brown Signed-off-by: Hardik Gohil Signed-off-by: Greg Kroah-Hartman

spi: introduce SPI_MODE_X_MASK macro

2024-02-23T07:41:51+00:00

[ Upstream commit 029b42d8519cef70c4fb5fcaccd08f1053ed2bf0 ] Provide a macro to filter all SPI_MODE_0,1,2,3 mode in one run. The latest SPI framework will parse the devicetree in following call sequence: of_register_spi_device() -> of_spi_parse_dt() So, driver do not need to pars the devicetree and will get prepared flags in the probe. On one hand it is good far most drivers. On other hand some drivers need to filter flags provide by SPI framework and apply know to work flags. This drivers may use SPI_MODE_X_MASK to filter MODE flags and set own, known flags: spi->flags &= ~SPI_MODE_X_MASK; spi->flags |= SPI_MODE_0; Signed-off-by: Oleksij Rempel Link: https://lore.kernel.org/r/20201027095724.18654-2-o.rempel@pengutronix.de Signed-off-by: Mark Brown Stable-dep-of: 6d710b769c1f ("serial: sc16is7xx: add check for unsupported SPI modes during probe") Signed-off-by: Sasha Levin

spi: Switch to signed types for *_native_cs SPI controller fields

2021-09-08T06:49:01+00:00

commit 35f3f8504c3b60a1ae5576e178b27fc0ddd6157d upstream. While fixing undefined behaviour the commit f60d7270c8a3 ("spi: Avoid undefined behaviour when counting unused native CSs") missed the case when all CSs are GPIOs and thus unused_native_cs will be evaluated to -1 in unsigned representation. This will falsely trigger a condition in the spi_get_gpio_descs(). Switch to signed types for *_native_cs SPI controller fields to fix above. Fixes: f60d7270c8a3 ("spi: Avoid undefined behaviour when counting unused native CSs") Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20210510131242.49455-1-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown Signed-off-by: Nobuhiro Iwamatsu (CIP) Signed-off-by: Greg Kroah-Hartman

spi: Fix use-after-free with devm_spi_alloc_*

2021-05-14T07:50:16+00:00

[ Upstream commit 794aaf01444d4e765e2b067cba01cc69c1c68ed9 ] 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 [] (refcount_warn_saturate) from [] (kobject_put+0x90/0x98) [] (kobject_put) from [] (put_device+0x20/0x24) r4:b6700140 [] (put_device) from [] (devm_spi_release_controller+0x3c/0x40) [] (devm_spi_release_controller) from [] (release_nodes+0x84/0xc4) r5:b6700180 r4:b6700100 [] (release_nodes) from [] (devres_release_all+0x5c/0x60) r8:b1638c54 r7:b117ad94 r6:b1638c10 r5:b117ad94 r4:b163dc10 [] (devres_release_all) from [] (__device_release_driver+0x144/0x1ec) r5:b117ad94 r4:b163dc10 [] (__device_release_driver) from [] (device_driver_detach+0x84/0xa0) r9:00000000 r8:00000000 r7:b117ad94 r6:b163dc54 r5:b1638c10 r4:b163dc10 [] (device_driver_detach) from [] (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: 5e844cc37a5c ("spi: Introduce device-managed SPI controller allocation") Signed-off-by: William A. Kennington III Link: https://lore.kernel.org/r/20210407095527.2771582-1-wak@google.com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin

spi: Introduce device-managed SPI controller allocation

2020-11-12T15:05:34+00:00

SPI driver probing currently comprises two steps, whereas removal comprises only one step: spi_alloc_master() spi_register_controller() spi_unregister_controller() That's because spi_unregister_controller() calls device_unregister() instead of device_del(), thereby releasing the reference on the spi_controller which was obtained by spi_alloc_master(). An SPI driver's private data is contained in the same memory allocation as the spi_controller struct. Thus, once spi_unregister_controller() has been called, the private data is inaccessible. But some drivers need to access it after spi_unregister_controller() to perform further teardown steps. Introduce devm_spi_alloc_master() and devm_spi_alloc_slave(), which release a reference on the spi_controller struct only after the driver has unbound, thereby keeping the memory allocation accessible. Change spi_unregister_controller() to not release a reference if the spi_controller was allocated by one of these new devm functions. The present commit is small enough to be backportable to stable. It allows fixing drivers which use the private data in their ->remove() hook after it's been freed. It also allows fixing drivers which neglect to release a reference on the spi_controller in the probe error path. Long-term, most SPI drivers shall be moved over to the devm functions introduced herein. The few that can't shall be changed in a treewide commit to explicitly release the last reference on the controller. That commit shall amend spi_unregister_controller() to no longer release a reference, thereby completing the migration. As a result, the behaviour will be less surprising and more consistent with subsystems such as IIO, which also includes the private data in the allocation of the generic iio_dev struct, but calls device_del() in iio_device_unregister(). Signed-off-by: Lukas Wunner Link: https://lore.kernel.org/r/272bae2ef08abd21388c98e23729886663d19192.1605121038.git.lukas@wunner.de Signed-off-by: Mark Brown

Merge tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

2020-10-24T17:33:08+00:00

Pull ARM SoC platform updates from Olof Johansson: "SoC changes, a substantial part of this is cleanup of some of the older platforms that used to have a bunch of board files. In particular: - Remove non-DT i.MX platforms that haven't seen activity in years, it's time to remove them. - A bunch of cleanup and removal of platform data for TI/OMAP platforms, moving over to genpd for power/reset control (yay!) - Major cleanup of Samsung S3C24xx and S3C64xx platforms, moving them closer to multiplatform support (not quite there yet, but getting close). There are a few other changes too, smaller fixlets, etc. For new platform support, the primary ones are: - New SoC: Hisilicon SD5203, ARM926EJ-S platform. - Cpufreq support for i.MX7ULP" * tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (121 commits) ARM: mstar: Select MStar intc ARM: stm32: Replace HTTP links with HTTPS ones ARM: debug: add UART early console support for SD5203 ARM: hisi: add support for SD5203 SoC ARM: omap3: enable off mode automatically clk: imx: imx35: Remove mx35_clocks_init() clk: imx: imx31: Remove mx31_clocks_init() clk: imx: imx27: Remove mx27_clocks_init() ARM: imx: Remove unused definitions ARM: imx35: Retrieve the IIM base address from devicetree ARM: imx3: Retrieve the AVIC base address from devicetree ARM: imx3: Retrieve the CCM base address from devicetree ARM: imx31: Retrieve the IIM base address from devicetree ARM: imx27: Retrieve the CCM base address from devicetree ARM: imx27: Retrieve the SYSCTRL base address from devicetree ARM: s3c64xx: bring back notes from removed debug-macro.S ARM: s3c24xx: fix Wunused-variable warning on !MMU ARM: samsung: fix PM debug build with DEBUG_LL but !MMU MAINTAINERS: mark linux-samsung-soc list non-moderated ARM: imx: Remove remnant board file support pieces ...

eeprom: at25: allow page sizes greater than 16 bit

2020-08-28T10:08:08+00:00

Storage technologies like FRAM have no "write pages", the whole chip can be written within one SPI transfer. For these chips, the page size can be set equal to the device size. Currently available devices are already bigger than 64 kiB. Signed-off-by: Christian Eggers Link: https://lore.kernel.org/r/20200727111218.26926-1-ceggers@arri.de Signed-off-by: Greg Kroah-Hartman

ARM: s3c24xx: spi: avoid hardcoding fiq number in driver

2020-08-20T15:43:45+00:00

The IRQ_EINT0 constant is a platform detail that is defined in mach/irqs.h and not visible to drivers once that header is made private. Since the same calculation already happens in s3c24xx_set_fiq, just return the value from there. Signed-off-by: Arnd Bergmann Acked-by: Mark Brown Link: https://lore.kernel.org/r/20200806182059.2431-31-krzk@kernel.org Signed-off-by: Krzysztof Kozlowski

ARM: s3c24xx: move spi fiq handler into platform

2020-08-19T19:45:38+00:00

The fiq handler needs access to some register definitions that should not be used directly by device drivers. Since this is closely related to the irqchip driver anyway, move it into the same place. Signed-off-by: Arnd Bergmann [krzk: Add a header guard in include/linux/spi/s3c24xx-fiq.h, fix SPDX comment style, update maintainer's entry] Co-developed-by: Krzysztof Kozlowski Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20200806182059.2431-23-krzk%40kernel.org Acked-by: Mark Brown

spi: correct kernel-doc inconsistency

2020-07-27T13:55:22+00:00

Silence documentation build warnings by correcting kernel-doc comment for spi_transfer struct. Signed-off-by: Colton Lewis Link: https://lore.kernel.org/r/20200725050242.279548-1-colton.w.lewis@protonmail.com Signed-off-by: Mark Brown