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2022-07-20Merge branch irq/loongarch into irq/irqchip-nextMarc Zyngier1-0/+1
* irq/loongarch: : . : Merge the long awaited IRQ support for the LoongArch architecture. : : From the cover letter: : : "Currently, LoongArch based processors (e.g. Loongson-3A5000) : can only work together with LS7A chipsets. The irq chips in : LoongArch computers include CPUINTC (CPU Core Interrupt : Controller), LIOINTC (Legacy I/O Interrupt Controller), : EIOINTC (Extended I/O Interrupt Controller), PCH-PIC (Main : Interrupt Controller in LS7A chipset), PCH-LPC (LPC Interrupt : Controller in LS7A chipset) and PCH-MSI (MSI Interrupt Controller)." : : Note that this comes with non-official, arch private ACPICA : definitions until the official ACPICA update is realeased. : . irqchip / ACPI: Introduce ACPI_IRQ_MODEL_LPIC for LoongArch irqchip: Add LoongArch CPU interrupt controller support irqchip: Add Loongson Extended I/O interrupt controller support irqchip/loongson-liointc: Add ACPI init support irqchip/loongson-pch-msi: Add ACPI init support irqchip/loongson-pch-pic: Add ACPI init support irqchip: Add Loongson PCH LPC controller support LoongArch: Prepare to support multiple pch-pic and pch-msi irqdomain LoongArch: Use ACPI_GENERIC_GSI for gsi handling genirq/generic_chip: Export irq_unmap_generic_chip ACPI: irq: Allow acpi_gsi_to_irq() to have an arch-specific fallback APCI: irq: Add support for multiple GSI domains LoongArch: Provisionally add ACPICA data structures Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-07-20genirq/generic_chip: Export irq_unmap_generic_chipJianmin Lv1-0/+1
Some irq controllers have to re-implement a private version for irq_generic_chip_ops, because they have a different xlate to translate hwirq. Export irq_unmap_generic_chip to allow reusing in drivers. Signed-off-by: Jianmin Lv <lvjianmin@loongson.cn> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/1658314292-35346-5-git-send-email-lvjianmin@loongson.cn
2022-07-07genirq: Provide an IRQ affinity mask in non-SMP configsSamuel Holland1-0/+8
IRQ affinity masks are not allocated in uniprocessor configurations. This requires special case non-SMP code in drivers for irqchips which have per-CPU enable or mask registers. Since IRQ affinity is always the same in a uniprocessor configuration, we can provide a correct affinity mask without allocating one per IRQ. By returning a real cpumask from irq_data_get_affinity_mask even when SMP is disabled, irqchip drivers which iterate over that mask will automatically do the right thing. Signed-off-by: Samuel Holland <samuel@sholland.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220701200056.46555-9-samuel@sholland.org
2022-07-07genirq: Return a const cpumask from irq_data_get_affinity_maskSamuel Holland1-5/+7
Now that the irq_data_update_affinity helper exists, enforce its use by returning a a const cpumask from irq_data_get_affinity_mask. Since the previous commit already updated places that needed to call irq_data_update_affinity, this commit updates the remaining code that either did not modify the cpumask or immediately passed the modified mask to irq_set_affinity. Signed-off-by: Samuel Holland <samuel@sholland.org> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220701200056.46555-8-samuel@sholland.org
2022-07-07genirq: Add and use an irq_data_update_affinity helperSamuel Holland1-0/+6
Some architectures and irqchip drivers modify the cpumask returned by irq_data_get_affinity_mask, usually by copying in to it. This is problematic for uniprocessor configurations, where the affinity mask should be constant, as it is known at compile time. Add and use a setter for the affinity mask, following the pattern of irq_data_update_effective_affinity. This allows the getter function to return a const cpumask pointer. Signed-off-by: Samuel Holland <samuel@sholland.org> Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # Xen bits Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220701200056.46555-7-samuel@sholland.org
2022-07-07genirq: Refactor accessors to use irq_data_get_affinity_maskSamuel Holland1-7/+7
A couple of functions directly reference the affinity mask. Route them through irq_data_get_affinity_mask so they will pick up any refactoring done there. Signed-off-by: Samuel Holland <samuel@sholland.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220701200056.46555-6-samuel@sholland.org
2022-04-19gpio: Don't fiddle with irqchips marked as immutableMarc Zyngier1-0/+2
In order to move away from gpiolib messing with the internals of unsuspecting irqchips, add a flag by which irqchips advertise that they are not to be messed with, and do solemnly swear that they correctly call into the gpiolib helpers when required. Also nudge the users into converting their drivers to the new model. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Bartosz Golaszewski <brgl@bgdev.pl> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220419141846.598305-2-maz@kernel.org
2022-02-15genirq: Allow irq_chip registration functions to take a const irq_chipMarc Zyngier1-3/+4
In order to let a const irqchip be fed to the irqchip layer, adjust the various prototypes. An extra cast in irq_set_chip()() is required to avoid a warning. Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20220209162607.1118325-3-maz@kernel.org
2022-02-10genirq: Kill irq_chip::parent_deviceMarc Zyngier1-2/+0
Now that noone is using irq_chip::parent_device in the tree, get rid of it. Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Bartosz Golaszewski <brgl@bgdev.pl> Link: https://lore.kernel.org/r/20220201120310.878267-13-maz@kernel.org
2021-10-28Merge branch irq/irq_cpu_offline into irq/irqchip-nextMarc Zyngier1-1/+4
* irq/irq_cpu_offline: : . : Make irq_cpu_{on,off}line() deprecated kernel API, and only : enable it for some obscure Cavium platform after having : moved all the other users away from it. : : Next step, drop the platform itself. : . genirq: Hide irq_cpu_{on,off}line() behind a deprecated option irqchip/mips-gic: Get rid of the reliance on irq_cpu_online() MIPS: loongson64: Drop call to irq_cpu_offline() Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-10-26genirq: Hide irq_cpu_{on,off}line() behind a deprecated optionMarc Zyngier1-1/+4
irq_cpu_{on,off}line() are now only used by the Octeon platform. Make their use conditional on this plaform being enabled, and otherwise hidden away. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Tested-by: Serge Semin <fancer.lancer@gmail.com> Link: https://lore.kernel.org/r/20211021170414.3341522-4-maz@kernel.org
2021-10-25irq: add generic_handle_arch_irq()Mark Rutland1-0/+1
Several architectures select GENERIC_IRQ_MULTI_HANDLER and branch to handle_arch_irq() without performing any entry accounting. Add a generic wrapper to handle the common irqentry work when invoking handle_arch_irq(). Where an architecture needs to perform some entry accounting itself, it will need to invoke handle_arch_irq() itself. In subsequent patches it will become the responsibilty of the entry code to set the irq regs when entering an IRQ (rather than deferring this to an irqchip handler), so generic_handle_arch_irq() is made to set the irq regs now. This can be redundant in some cases, but is never harmful as saving/restoring the old regs nests safely. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Guo Ren <guoren@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de>
2021-08-10genirq: Provide IRQCHIP_AFFINITY_PRE_STARTUPThomas Gleixner1-0/+2
X86 IO/APIC and MSI interrupts (when used without interrupts remapping) require that the affinity setup on startup is done before the interrupt is enabled for the first time as the non-remapped operation mode cannot safely migrate enabled interrupts from arbitrary contexts. Provide a new irq chip flag which allows affected hardware to request this. This has to be opt-in because there have been reports in the past that some interrupt chips cannot handle affinity setting before startup. Fixes: 18404756765c ("genirq: Expose default irq affinity mask (take 3)") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210729222542.779791738@linutronix.de
2021-05-17genirq: Add a IRQF_NO_DEBUG flagThomas Gleixner1-0/+2
The whole call to note_interrupt() can be avoided or return early when interrupts would be marked accordingly. For IPI handlers which always return HANDLED the whole procedure is pretty pointless to begin with. Add a IRQF_NO_DEBUG flag and mark the interrupt accordingly if supplied when the interrupt is requested. When noirqdebug is set on the kernel commandline, then the interrupt is marked unconditionally so that there is only one condition in the hotpath to evaluate. [ clg: Add changelog ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/7a8ad02f-63a8-c1aa-fdd1-39d973593d02@kaod.org
2021-04-26Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds1-0/+2
Pull arm64 updates from Catalin Marinas: - MTE asynchronous support for KASan. Previously only synchronous (slower) mode was supported. Asynchronous is faster but does not allow precise identification of the illegal access. - Run kernel mode SIMD with softirqs disabled. This allows using NEON in softirq context for crypto performance improvements. The conditional yield support is modified to take softirqs into account and reduce the latency. - Preparatory patches for Apple M1: handle CPUs that only have the VHE mode available (host kernel running at EL2), add FIQ support. - arm64 perf updates: support for HiSilicon PA and SLLC PMU drivers, new functions for the HiSilicon HHA and L3C PMU, cleanups. - Re-introduce support for execute-only user permissions but only when the EPAN (Enhanced Privileged Access Never) architecture feature is available. - Disable fine-grained traps at boot and improve the documented boot requirements. - Support CONFIG_KASAN_VMALLOC on arm64 (only with KASAN_GENERIC). - Add hierarchical eXecute Never permissions for all page tables. - Add arm64 prctl(PR_PAC_{SET,GET}_ENABLED_KEYS) allowing user programs to control which PAC keys are enabled in a particular task. - arm64 kselftests for BTI and some improvements to the MTE tests. - Minor improvements to the compat vdso and sigpage. - Miscellaneous cleanups. * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (86 commits) arm64/sve: Add compile time checks for SVE hooks in generic functions arm64/kernel/probes: Use BUG_ON instead of if condition followed by BUG. arm64: pac: Optimize kernel entry/exit key installation code paths arm64: Introduce prctl(PR_PAC_{SET,GET}_ENABLED_KEYS) arm64: mte: make the per-task SCTLR_EL1 field usable elsewhere arm64/sve: Remove redundant system_supports_sve() tests arm64: fpsimd: run kernel mode NEON with softirqs disabled arm64: assembler: introduce wxN aliases for wN registers arm64: assembler: remove conditional NEON yield macros kasan, arm64: tests supports for HW_TAGS async mode arm64: mte: Report async tag faults before suspend arm64: mte: Enable async tag check fault arm64: mte: Conditionally compile mte_enable_kernel_*() arm64: mte: Enable TCO in functions that can read beyond buffer limits kasan: Add report for async mode arm64: mte: Drop arch_enable_tagging() kasan: Add KASAN mode kernel parameter arm64: mte: Add asynchronous mode support arm64: Get rid of CONFIG_ARM64_VHE arm64: Cope with CPUs stuck in VHE mode ...
2021-03-24genirq: Allow architectures to override set_handle_irq() fallbackMarc Zyngier1-0/+2
Some architectures want to provide the generic set_handle_irq() API, but for structural reasons need to provide their own implementation. For example, arm64 needs to do this to provide uniform set_handle_irq() and set_handle_fiq() registration functions. Make this possible by allowing architectures to provide their own implementation of set_handle_irq when CONFIG_GENERIC_IRQ_MULTI_HANDLER is not selected. Signed-off-by: Marc Zyngier <maz@kernel.org> [Mark: expand commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Hector Martin <marcan@marcan.st> Cc: James Morse <james.morse@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210315115629.57191-2-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-03-22irq: Fix typos in commentsIngo Molnar1-2/+2
Fix ~36 single-word typos in the IRQ, irqchip and irqdomain code comments. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Marc Zyngier <maz@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-02-05genirq: Prevent [devm_]irq_alloc_desc from returning irq 0Hans de Goede1-2/+2
Since commit a85a6c86c25b ("driver core: platform: Clarify that IRQ 0 is invalid"), having a linux-irq with number 0 will trigger a WARN() when calling platform_get_irq*() to retrieve that linux-irq. Since [devm_]irq_alloc_desc allocs a single irq and since irq 0 is not used on some systems, it can return 0, triggering that WARN(). This happens e.g. on Intel Bay Trail and Cherry Trail devices using the LPE audio engine for HDMI audio: 0 is an invalid IRQ number WARNING: CPU: 3 PID: 472 at drivers/base/platform.c:238 platform_get_irq_optional+0x108/0x180 Modules linked in: snd_hdmi_lpe_audio(+) ... Call Trace: platform_get_irq+0x17/0x30 hdmi_lpe_audio_probe+0x4a/0x6c0 [snd_hdmi_lpe_audio] ---[ end trace ceece38854223a0b ]--- Change the 'from' parameter passed to __[devm_]irq_alloc_descs() by the [devm_]irq_alloc_desc macros from 0 to 1, so that these macros will no longer return 0. Fixes: a85a6c86c25b ("driver core: platform: Clarify that IRQ 0 is invalid") Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20201221185647.226146-1-hdegoede@redhat.com
2020-12-15genirq: Provide irq_get_effective_affinity()Thomas Gleixner1-0/+7
Provide an accessor to the effective interrupt affinity mask. Going to be used to replace open coded fiddling with the irq descriptor. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201210194042.967177918@linutronix.de
2020-12-15Merge tag 'irqchip-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/coreThomas Gleixner1-1/+0
Pull irqchip updates for 5.11 from Marc Zyngier: - Preliminary support for managed interrupts on platform devices - Correctly identify allocation of MSIs proxyied by another device - Remove the fasteoi IPI flow which has been proved useless - Generalise the Ocelot support to new SoCs - Improve GICv4.1 vcpu entry, matching the corresponding KVM optimisation - Work around spurious interrupts on Qualcomm PDC - Random fixes and cleanups Link: https://lore.kernel.org/r/20201212135626.1479884-1-maz@kernel.org
2020-12-11Revert "genirq: Add fasteoi IPI flow"Valentin Schneider1-1/+0
handle_percpu_devid_fasteoi_ipi() has no more users, and handle_percpu_devid_irq() can do all that it was supposed to do. Get rid of it. This reverts commit c5e5ec033c4ab25c53f1fd217849e75deb0bf7bf. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20201109094121.29975-6-valentin.schneider@arm.com
2020-11-14genirq: Remove GENERIC_IRQ_LEGACY_ALLOC_HWIRQThomas Gleixner1-15/+0
Commit bb9d812643d8 ("arch: remove tile port") removed the last user of this cruft two years ago... Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/87eekvac06.fsf@nanos.tec.linutronix.de
2020-10-06Merge branch 'irq/qcom-pdc-wakeup' into irq/irqchip-nextMarc Zyngier1-19/+30
Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-10-06genirq/PM: Introduce IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND flagMaulik Shah1-19/+30
An interrupt that is disabled/masked but set for wakeup may still need to be able to wake up the system from sleep states like "suspend to RAM". To that effect, introduce the IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND flag. If the irqchip have this flag set, the irq PM code will enable/unmask the irqs that are marked for wakeup, but that are in a disabled state. On resume, such irqs will be restored back to their disabled state. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Maulik Shah <mkshah@codeaurora.org> [maz: commit message fix-up] Signed-off-by: Marc Zyngier <maz@kernel.org> Tested-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/1601267524-20199-4-git-send-email-mkshah@codeaurora.org
2020-09-28Merge branch 'irq/ipi-as-irq', remote-tracking branches 'origin/irq/dw' and 'origin/irq/owl' into irq/irqchip-nextMarc Zyngier1-0/+6
Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-09-25genirq: Add stub for set_handle_irq() when !GENERIC_IRQ_MULTI_HANDLERZhen Lei1-0/+6
In order to avoid compilation errors when a driver references set_handle_irq(), but that the architecture doesn't select GENERIC_IRQ_MULTI_HANDLER, add a stub function that will just WARN_ON_ONCE() if ever used. Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> [maz: commit message] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200924071754.4509-2-thunder.leizhen@huawei.com
2020-09-13genirq: Allow interrupts to be excluded from /proc/interruptsMarc Zyngier1-1/+3
A number of architectures implement IPI statistics directly, duplicating the core kstat_irqs accounting. As we move IPIs to being actual IRQs, we would end-up with a confusing display in /proc/interrupts (where the IPIs would appear twice). In order to solve this, allow interrupts to be flagged as "hidden", which excludes them from /proc/interrupts. Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-09-13genirq: Add fasteoi IPI flowMarc Zyngier1-0/+1
For irqchips using the fasteoi flow, IPIs are a bit special. They need to be EOI'd early (before calling the handler), as funny things may happen in the handler (they do not necessarily behave like a normal interrupt). Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-07-27genirq/affinity: Make affinity setting if activated opt-inThomas Gleixner1-0/+13
John reported that on a RK3288 system the perf per CPU interrupts are all affine to CPU0 and provided the analysis: "It looks like what happens is that because the interrupts are not per-CPU in the hardware, armpmu_request_irq() calls irq_force_affinity() while the interrupt is deactivated and then request_irq() with IRQF_PERCPU | IRQF_NOBALANCING. Now when irq_startup() runs with IRQ_STARTUP_NORMAL, it calls irq_setup_affinity() which returns early because IRQF_PERCPU and IRQF_NOBALANCING are set, leaving the interrupt on its original CPU." This was broken by the recent commit which blocked interrupt affinity setting in hardware before activation of the interrupt. While this works in general, it does not work for this particular case. As contrary to the initial analysis not all interrupt chip drivers implement an activate callback, the safe cure is to make the deferred interrupt affinity setting at activation time opt-in. Implement the necessary core logic and make the two irqchip implementations for which this is required opt-in. In hindsight this would have been the right thing to do, but ... Fixes: baedb87d1b53 ("genirq/affinity: Handle affinity setting on inactive interrupts correctly") Reported-by: John Keeping <john@metanate.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Marc Zyngier <maz@kernel.org> Acked-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/87blk4tzgm.fsf@nanos.tec.linutronix.de
2020-04-19Merge tag 'irq-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-2/+0
Pull irq fixes from Thomas Gleixner: "A set of fixes/updates for the interrupt subsystem: - Remove setup_irq() and remove_irq(). All users have been converted so remove them before new users surface. - A set of bugfixes for various interrupt chip drivers - Add a few missing static attributes to address sparse warnings" * tag 'irq-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/irq-bcm7038-l1: Make bcm7038_l1_of_init() static irqchip/irq-mvebu-icu: Make legacy_bindings static irqchip/meson-gpio: Fix HARDIRQ-safe -> HARDIRQ-unsafe lock order irqchip/sifive-plic: Fix maximum priority threshold value irqchip/ti-sci-inta: Fix processing of masked irqs irqchip/mbigen: Free msi_desc on device teardown irqchip/gic-v4.1: Update effective affinity of virtual SGIs irqchip/gic-v4.1: Add support for VPENDBASER's Dirty+Valid signaling genirq: Remove setup_irq() and remove_irq()
2020-04-18irq.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva1-2/+2
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-14genirq: Remove setup_irq() and remove_irq()afzal mohammed1-2/+0
Now that all the users of setup_irq() & remove_irq() have been replaced by request_irq() & free_irq() respectively, delete them. Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lkml.kernel.org/r/0aa8771ada1ac8e1312f6882980c9c08bd023148.1585320721.git.afzal.mohd.ma@gmail.com
2020-03-08genirq: Add protection against unsafe usage of generic_handle_irq()Thomas Gleixner1-0/+13
In general calling generic_handle_irq() with interrupts disabled from non interrupt context is harmless. For some interrupt controllers like the x86 trainwrecks this is outright dangerous as it might corrupt state if an interrupt affinity change is pending. Add infrastructure which allows to mark interrupts as unsafe and catch such usage in generic_handle_irq(). Reported-by: sathyanarayanan.kuppuswamy@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lkml.kernel.org/r/20200306130623.590923677@linutronix.de
2020-02-01x86/apic/msi: Plug non-maskable MSI affinity raceThomas Gleixner1-0/+18
Evan tracked down a subtle race between the update of the MSI message and the device raising an interrupt internally on PCI devices which do not support MSI masking. The update of the MSI message is non-atomic and consists of either 2 or 3 sequential 32bit wide writes to the PCI config space. - Write address low 32bits - Write address high 32bits (If supported by device) - Write data When an interrupt is migrated then both address and data might change, so the kernel attempts to mask the MSI interrupt first. But for MSI masking is optional, so there exist devices which do not provide it. That means that if the device raises an interrupt internally between the writes then a MSI message is sent built from half updated state. On x86 this can lead to spurious interrupts on the wrong interrupt vector when the affinity setting changes both address and data. As a consequence the device interrupt can be lost causing the device to become stuck or malfunctioning. Evan tried to handle that by disabling MSI accross an MSI message update. That's not feasible because disabling MSI has issues on its own: If MSI is disabled the PCI device is routing an interrupt to the legacy INTx mechanism. The INTx delivery can be disabled, but the disablement is not working on all devices. Some devices lose interrupts when both MSI and INTx delivery are disabled. Another way to solve this would be to enforce the allocation of the same vector on all CPUs in the system for this kind of screwed devices. That could be done, but it would bring back the vector space exhaustion problems which got solved a few years ago. Fortunately the high address (if supported by the device) is only relevant when X2APIC is enabled which implies interrupt remapping. In the interrupt remapping case the affinity setting is happening at the interrupt remapping unit and the PCI MSI message is programmed only once when the PCI device is initialized. That makes it possible to solve it with a two step update: 1) Target the MSI msg to the new vector on the current target CPU 2) Target the MSI msg to the new vector on the new target CPU In both cases writing the MSI message is only changing a single 32bit word which prevents the issue of inconsistency. After writing the final destination it is necessary to check whether the device issued an interrupt while the intermediate state #1 (new vector, current CPU) was in effect. This is possible because the affinity change is always happening on the current target CPU. The code runs with interrupts disabled, so the interrupt can be detected by checking the IRR of the local APIC. If the vector is pending in the IRR then the interrupt is retriggered on the new target CPU by sending an IPI for the associated vector on the target CPU. This can cause spurious interrupts on both the local and the new target CPU. 1) If the new vector is not in use on the local CPU and the device affected by the affinity change raised an interrupt during the transitional state (step #1 above) then interrupt entry code will ignore that spurious interrupt. The vector is marked so that the 'No irq handler for vector' warning is supressed once. 2) If the new vector is in use already on the local CPU then the IRR check might see an pending interrupt from the device which is using this vector. The IPI to the new target CPU will then invoke the handler of the device, which got the affinity change, even if that device did not issue an interrupt 3) If the new vector is in use already on the local CPU and the device affected by the affinity change raised an interrupt during the transitional state (step #1 above) then the handler of the device which uses that vector on the local CPU will be invoked. expose issues in device driver interrupt handlers which are not prepared to handle a spurious interrupt correctly. This not a regression, it's just exposing something which was already broken as spurious interrupts can happen for a lot of reasons and all driver handlers need to be able to deal with them. Reported-by: Evan Green <evgreen@chromium.org> Debugged-by: Evan Green <evgreen@chromium.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Evan Green <evgreen@chromium.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/87imkr4s7n.fsf@nanos.tec.linutronix.de
2019-11-16genirq: Introduce irq_chip_get/set_parent_state callsMaulik Shah1-0/+6
On certain QTI chipsets some GPIOs are direct-connect interrupts to the GIC to be used as regular interrupt lines. When the GPIOs are not used for interrupt generation the interrupt line is disabled. But disabling the interrupt at GIC does not prevent the interrupt to be reported as pending at GIC_ISPEND. Later, when drivers call enable_irq() on the interrupt, an unwanted interrupt occurs. Introduce get and set methods for irqchip's parent to clear it's pending irq state. This then can be invoked by the GPIO interrupt controller on the parents in it hierarchy to clear the interrupt before enabling the interrupt. Signed-off-by: Maulik Shah <mkshah@codeaurora.org> Signed-off-by: Lina Iyer <ilina@codeaurora.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Link: https://lore.kernel.org/r/1573855915-9841-7-git-send-email-ilina@codeaurora.org [updated commit text and minor code fixes]
2019-05-01genirq: Introduce irq_chip_{request,release}_resource_parent() apisLokesh Vutla1-0/+2
Introduce irq_chip_{request,release}_resource_parent() apis so that these can be used in hierarchical irqchips. Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-03-21genirq: Fix typo in comment of IRQD_MOVE_PCNTXTPeter Xu1-1/+1
Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Dou Liyang <douliyangs@gmail.com> Cc: Julien Thierry <julien.thierry@arm.com> Link: https://lkml.kernel.org/r/20190318065123.11862-1-peterx@redhat.com
2019-03-08Merge tag 'gpio-v5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpioLinus Torvalds1-0/+1
Pull GPIO updates from Linus Walleij: "This is the bulk of GPIO changes for the v5.1 cycle: Core changes: - The big change this time around is the irqchip handling in the qualcomm pin controllers, closely coupled with the gpiochip. This rework, in a classic fall-between-the-chairs fashion has been sidestepped for too long. The Qualcomm IRQchips using the SPMI and SSBI transport mechanisms have been rewritten to use hierarchical irqchip. This creates the base from which I intend to gradually pull support for hierarchical irqchips into the gpiolib irqchip helpers to cut down on duplicate code. We have too many hacks in the kernel because people have been working around the missing hierarchical irqchip for years, and once it was there, noone understood it for a while. We are now slowly adapting to using it. This is why this pull requests include changes to MFD, SPMI, IRQchip core and some ARM Device Trees pertaining to the Qualcomm chip family. Since Qualcomm have so many chips and such large deployments it is paramount that this platform gets this right, and now it (hopefully) does. - Core support for pull-up and pull-down configuration, also from the device tree. When a simple GPIO chip supports an "off or on" pull-up or pull-down resistor, we provide a way to set this up using machine descriptors or device tree. If more elaborate control of pull up/down (such as resistance shunt setting) is required, drivers should be phased over to use pin control. We do not yet provide a userspace ABI for this pull up-down setting but I suspect the makers are going to ask for it soon enough. PCA953x is the first user of this new API. - The GPIO mockup driver has been revamped after some discussion improving the IRQ simulator in the process. The idea is to make it possible to use the mockup for both testing and virtual prototyping, e.g. when you do not yet have a GPIO expander to play with but really want to get something to develop code around before hardware is available. It's neat. The blackbox testing usecase is currently making its way into kernelci. - ACPI GPIO core preserves non direction flags when updating flags. - A new device core helper for devm_platform_ioremap_resource() is funneled through the GPIO tree with Greg's ACK. New drivers: - TQ-Systems QTMX86 GPIO controllers (using port-mapped I/O) - Gateworks PLD GPIO driver (vaccumed up from OpenWrt) - AMD G-Series PCH (Platform Controller Hub) GPIO driver. - Fintek F81804 & F81966 subvariants. - PCA953x now supports NXP PCAL6416. Driver improvements: - IRQ support on the Nintendo Wii (Hollywood) GPIO. - get_direction() support for the MVEBU driver. - Set the right output level on SAMA5D2. - Drop the unused irq trigger setting on the Spreadtrum driver. - Wakeup support for PCA953x. - A slew of cleanups in the various Intel drivers" * tag 'gpio-v5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (110 commits) gpio: gpio-omap: fix level interrupt idling gpio: amd-fch: Set proper output level for direction_output x86: apuv2: remove unused variable gpio: pca953x: Use PCA_LATCH_INT platform/x86: fix PCENGINES_APU2 Kconfig warning gpio: pca953x: Fix dereference of irq data in shutdown gpio: amd-fch: Fix type error found by sparse gpio: amd-fch: Drop const from resource gpio: mxc: add check to return defer probe if clock tree NOT ready gpio: ftgpio: Register per-instance irqchip gpio: ixp4xx: Add DT bindings x86: pcengines apuv2 gpio/leds/keys platform driver gpio: AMD G-Series PCH gpio driver drivers: depend on HAS_IOMEM for devm_platform_ioremap_resource() gpio: tqmx86: Set proper output level for direction_output gpio: sprd: Change to use SoC compatible string gpio: sprd: Use SoC compatible string instead of wildcard string gpio: of: Handle both enable-gpio{,s} gpio: of: Restrict enable-gpio quirk to regulator-gpio gpio: davinci: use devm_platform_ioremap_resource() ...
2019-02-13genirq: introduce irq_chip_mask_ack_parent()Linus Walleij1-0/+1
The hierarchical irqchip never before ran into a situation where the parent is not "simple", i.e. does not implement .irq_ack() and .irq_mask() like most, but the qcom-pm8xxx.c happens to implement only .irq_mask_ack(). Since we want to make ssbi-gpio a hierarchical child of this irqchip, it must *also* only implement .irq_mask_ack() and call down to the parent, and for this we of course need irq_chip_mask_ack_parent(). Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Brian Masney <masneyb@onstation.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-02-05genirq: Provide NMI handlersJulien Thierry1-0/+3
Provide flow handlers that are NMI safe for interrupts and percpu_devid interrupts. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-05genirq: Provide basic NMI management for interrupt linesJulien Thierry1-0/+7
Add functionality to allocate interrupt lines that will deliver IRQs as Non-Maskable Interrupts. These allocations are only successful if the irqchip provides the necessary support and allows NMI delivery for the interrupt line. Interrupt lines allocated for NMI delivery must be enabled/disabled through enable_nmi/disable_nmi_nosync to keep their state consistent. To treat a PERCPU IRQ as NMI, the interrupt must not be shared nor threaded, the irqchip directly managing the IRQ must be the root irqchip and the irqchip cannot be behind a slow bus. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-12-19genirq/core: Introduce struct irq_affinity_descDou Liyang1-2/+4
The interrupt affinity management uses straight cpumask pointers to convey the automatically assigned affinity masks for managed interrupts. The core interrupt descriptor allocation also decides based on the pointer being non NULL whether an interrupt is managed or not. Devices which use managed interrupts usually have two classes of interrupts: - Interrupts for multiple device queues - Interrupts for general device management Currently both classes are treated the same way, i.e. as managed interrupts. The general interrupts get the default affinity mask assigned while the device queue interrupts are spread out over the possible CPUs. Treating the general interrupts as managed is both a limitation and under certain circumstances a bug. Assume the following situation: default_irq_affinity = 4..7 So if CPUs 4-7 are offlined, then the core code will shut down the device management interrupts because the last CPU in their affinity mask went offline. It's also a limitation because it's desired to allow manual placement of the general device interrupts for various reasons. If they are marked managed then the interrupt affinity setting from both user and kernel space is disabled. To remedy that situation it's required to convey more information than the cpumasks through various interfaces related to interrupt descriptor allocation. Instead of adding yet another argument, create a new data structure 'irq_affinity_desc' which for now just contains the cpumask. This struct can be expanded to convey auxilliary information in the next step. No functional change, just preparatory work. [ tglx: Simplified logic and clarified changelog ] Suggested-by: Thomas Gleixner <tglx@linutronix.de> Suggested-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Dou Liyang <douliyangs@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-pci@vger.kernel.org Cc: kashyap.desai@broadcom.com Cc: shivasharan.srikanteshwara@broadcom.com Cc: sumit.saxena@broadcom.com Cc: ming.lei@redhat.com Cc: hch@lst.de Cc: douliyang1@huawei.com Link: https://lkml.kernel.org/r/20181204155122.6327-2-douliyangs@gmail.com
2018-09-18irq/matrix: Spread managed interrupts on allocationDou Liyang1-1/+2
Linux spreads out the non managed interrupt across the possible target CPUs to avoid vector space exhaustion. Managed interrupts are treated differently, as for them the vectors are reserved (with guarantee) when the interrupt descriptors are initialized. When the interrupt is requested a real vector is assigned. The assignment logic uses the first CPU in the affinity mask for assignment. If the interrupt has more than one CPU in the affinity mask, which happens when a multi queue device has less queues than CPUs, then doing the same search as for non managed interrupts makes sense as it puts the interrupt on the least interrupt plagued CPU. For single CPU affine vectors that's obviously a NOOP. Restructre the matrix allocation code so it does the 'best CPU' search, add the sanity check for an empty affinity mask and adapt the call site in the x86 vector management code. [ tglx: Added the empty mask check to the core and improved change log ] Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20180908175838.14450-2-dou_liyang@163.com
2018-06-22genirq/debugfs: Add missing IRQCHIP_SUPPORTS_LEVEL_MSI debugMarc Zyngier1-0/+1
Debug is missing the IRQCHIP_SUPPORTS_LEVEL_MSI debug entry, making debugfs slightly less useful. Take this opportunity to also add a missing comment in the definition of IRQCHIP_SUPPORTS_LEVEL_MSI. Fixes: 6988e0e0d283 ("genirq/msi: Limit level-triggered MSI to platform devices") Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Yang Yingliang <yangyingliang@huawei.com> Cc: Sumit Garg <sumit.garg@linaro.org> Link: https://lkml.kernel.org/r/20180622095254.5906-2-marc.zyngier@arm.com
2018-06-10Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-1/+6
Pull x86 updates and fixes from Thomas Gleixner: - Fix the (late) fallout from the vector management rework causing hlist corruption and irq descriptor reference leaks caused by a missing sanity check. The straight forward fix triggered another long standing issue to surface. The pre rework code hid the issue due to being way slower, but now the chance that user space sees an EBUSY error return when updating irq affinities is way higher, though quite a bunch of userspace tools do not handle it properly despite the fact that EBUSY could be returned for at least 10 years. It turned out that the EBUSY return can be avoided completely by utilizing the existing delayed affinity update mechanism for irq remapped scenarios as well. That's a bit more error handling in the kernel, but avoids fruitless fingerpointing discussions with tool developers. - Decouple PHYSICAL_MASK from AMD SME as its going to be required for the upcoming Intel memory encryption support as well. - Handle legacy device ACPI detection properly for newer platforms - Fix the wrong argument ordering in the vector allocation tracepoint - Simplify the IDT setup code for the APIC=n case - Use the proper string helpers in the MTRR code - Remove a stale unused VDSO source file - Convert the microcode update lock to a raw spinlock as its used in atomic context. * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/intel_rdt: Enable CMT and MBM on new Skylake stepping x86/apic/vector: Print APIC control bits in debugfs genirq/affinity: Defer affinity setting if irq chip is busy x86/platform/uv: Use apic_ack_irq() x86/ioapic: Use apic_ack_irq() irq_remapping: Use apic_ack_irq() x86/apic: Provide apic_ack_irq() genirq/migration: Avoid out of line call if pending is not set genirq/generic_pending: Do not lose pending affinity update x86/apic/vector: Prevent hlist corruption and leaks x86/vector: Fix the args of vector_alloc tracepoint x86/idt: Simplify the idt_setup_apic_and_irq_gates() x86/platform/uv: Remove extra parentheses x86/mm: Decouple dynamic __PHYSICAL_MASK from AMD SME x86: Mark native_set_p4d() as __always_inline x86/microcode: Make the late update update_lock a raw lock for RT x86/mtrr: Convert to use strncpy_from_user() helper x86/mtrr: Convert to use match_string() helper x86/vdso: Remove unused file x86/i8237: Register device based on FADT legacy boot flag
2018-06-06genirq/migration: Avoid out of line call if pending is not setThomas Gleixner1-1/+6
The upcoming fix for the -EBUSY return from affinity settings requires to use the irq_move_irq() functionality even on irq remapped interrupts. To avoid the out of line call, move the check for the pending bit into an inline helper. Preparatory change for the real fix. No functional change. Fixes: dccfe3147b42 ("x86/vector: Simplify vector move cleanup") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Joerg Roedel <jroedel@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <liu.song.a23@gmail.com> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: stable@vger.kernel.org Cc: Mike Travis <mike.travis@hpe.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Tariq Toukan <tariqt@mellanox.com> Cc: Dou Liyang <douly.fnst@cn.fujitsu.com> Link: https://lkml.kernel.org/r/20180604162224.471925894@linutronix.de
2018-05-13genirq/msi: Limit level-triggered MSI to platform devicesMarc Zyngier1-0/+1
Nobody would be insane enough to try and use level triggered MSIs on PCI, but let's make sure it doesn't happen. Also, let's mandate that the irqchip backing the platform MSI domain is providing the IRQCHIP_SUPPORTS_LEVEL_MSI flag. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Rob Herring <robh@kernel.org> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Cc: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lkml.kernel.org/r/20180508121438.11301-3-marc.zyngier@arm.com
2018-03-14genirq: Add CONFIG_GENERIC_IRQ_MULTI_HANDLERPalmer Dabbelt1-0/+18
The arm multi irq handler registration mechanism has been copied into a handful of architectures, including arm64 and openrisc. RISC-V needs the same mechanism. Instead of adding yet another copy for RISC-V copy the arm implementation into the core code depending on a new Kconfig symbol: CONFIG_GENERIC_MULTI_IRQ_HANDLER. Subsequent patches will convert the various architectures. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: jonas@southpole.se Cc: catalin.marinas@arm.com Cc: Will Deacon <will.deacon@arm.com> Cc: linux@armlinux.org.uk Cc: stefan.kristiansson@saunalahti.fi Cc: openrisc@lists.librecores.org Cc: shorne@gmail.com Cc: linux-riscv@lists.infradead.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lkml.kernel.org/r/20180307235731.22627-2-palmer@sifive.com
2018-02-25genirq: Drop 5 #included header files from irq.hRandy Dunlap1-5/+0
<linux/irq.h> does not use nor need several of its #included files, so drop those header files from irq.h. <linux/irq.h> is currently #included in around 1135 C source files (oops, I didn't count other header files that #include it), making it the 29th most-used header file. Build tested on i386 and x86_64 * (allnoconfig, tiny.config, defconfig, allyesconfig, and allmodconfig) and x64_64 allmodconfig + SMP=disabled. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/02745e91-c117-74b5-d043-dceb3d4bb4e0@infradead.org
2017-12-29genirq: Introduce IRQD_CAN_RESERVE flagThomas Gleixner1-0/+17
Add a new flag to mark interrupts which can use reservation mode. This is going to be used in subsequent patches to disable reservation mode for a certain class of MSI devices. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Alexandru Chirvasitu <achirvasub@gmail.com> Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Dou Liyang <douly.fnst@cn.fujitsu.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Maciej W. Rozycki <macro@linux-mips.org> Cc: Mikael Pettersson <mikpelinux@gmail.com> Cc: Josh Poulson <jopoulso@microsoft.com> Cc: Mihai Costache <v-micos@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: linux-pci@vger.kernel.org Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Dexuan Cui <decui@microsoft.com> Cc: Simon Xiao <sixiao@microsoft.com> Cc: Saeed Mahameed <saeedm@mellanox.com> Cc: Jork Loeser <Jork.Loeser@microsoft.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: devel@linuxdriverproject.org Cc: KY Srinivasan <kys@microsoft.com> Cc: Alan Cox <alan@linux.intel.com> Cc: Sakari Ailus <sakari.ailus@intel.com>, Cc: linux-media@vger.kernel.org