kernel/drivers/base/regmap/regmap-irq.c, branch linux-rolling-stable

regmap: irq: Avoid lockdep warnings with nested regmap-irq chips

2025-08-01T12:37:07Z

While handling interrupts through regmap-irq we use a mutex to protect the updates we are caching while genirq runs in atomic context. Russell King reported that while running on the nVidia Jetson Xavier NX this generates lockdep warnings since that platform has a regmap-irq for the max77686 RTC which is a child of a max77620 which also uses regmap-irq. [ 46.723127] rtcwake/3984 is trying to acquire lock: [ 46.723235] ffff0000813b2c68 (&d->lock){+.+.}-{4:4}, at: regmap_irq_lock+0x18/0x24 [ 46.723452] but task is already holding lock: [ 46.723556] ffff00008504dc68 (&d->lock){+.+.}-{4:4}, at: regmap_irq_lock+0x18/0x24 This happens because by default lockdep uses a single lockdep class for all mutexes initialised from a single mutex_init() call and is unable to tell that two distinct mutex are being taken and verify that the ordering of operations is safe. This should be a very rare situation since normally anything using regmap-irq will be a leaf interrupt controller due to being on a slow bus like I2C. We can avoid these warnings by providing the lockdep key for the regmap-irq explicitly, allocating one for each chip so that lockdep can distinguish between them. Thanks to Russell for the report and analysis. Reported-by: Russell King (Oracle) Tested-by: Russell King (Oracle) Reviewed-by: Russell King (Oracle) Signed-off-by: Mark Brown Link: https://patch.msgid.link/20250731-regmap-irq-nesting-v1-2-98b4d1bf20f0@kernel.org Signed-off-by: Mark Brown

regmap: irq: Free the regmap-irq mutex

2025-08-01T12:37:06Z

We do not currently free the mutex allocated by regmap-irq, do so. Tested-by: Russell King (Oracle) Reviewed-by: Russell King (Oracle) Signed-off-by: Mark Brown Link: https://patch.msgid.link/20250731-regmap-irq-nesting-v1-1-98b4d1bf20f0@kernel.org Signed-off-by: Mark Brown

regmap: irq: Add support for chips without separate IRQ status

2025-05-22T12:11:50Z

Some GPIO chips allow to rise an IRQ on GPIO level changes but do not provide an IRQ status for each separate line: only the current gpio level can be retrieved. Add support for these chips, emulating IRQ status by comparing GPIO levels with the levels during the previous interrupt. Signed-off-by: Mathieu Dubois-Briand Reviewed-by: Andy Shevchenko Link: https://patch.msgid.link/20250522-mdb-max7360-support-v9-5-74fc03517e41@bootlin.com Signed-off-by: Mark Brown

regmap-irq: Use dedicated interrupt wake setters

2025-05-21T15:04:11Z

Use enable_irq_wake() and disable_irq_wake() instead of calling low-level irq_set_irq_wake() with a parameter. No functional changes. Signed-off-by: Andy Shevchenko Link: https://patch.msgid.link/20250521135538.1086717-1-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown

Merge tag 'regmap-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap

2025-03-29T21:31:39Z

Pull regmap updates from Mark Brown: "Only a couple of small patches this release, one refactoring struct regmap to pack it more efficiently and another which makes our way of setting all bits consistent in the regmap-irq code" * tag 'regmap-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: regmap: irq: Use one way of setting all bits in the register regmap: Reorder 'struct regmap'

regmap: irq: Use one way of setting all bits in the register

2025-02-06T20:46:09Z

Currently there are two ways of how we represent all bits set, i.e. UINT_MAX and GENMASK(31, 0). Use the former as the single way of doing that, which is crystal clear on how we fill the unsigned int value. Signed-off-by: Andy Shevchenko Link: https://patch.msgid.link/20250206191644.1132869-1-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown

regmap-irq: Add missing kfree()

2025-02-05T11:55:42Z

Add kfree() for "d->main_status_buf" to the error-handling path to prevent a memory leak. Fixes: a2d21848d921 ("regmap: regmap-irq: Add main status register support") Cc: stable@vger.kernel.org # v5.1+ Signed-off-by: Jiasheng Jiang Link: https://patch.msgid.link/20250205004343.14413-1-jiashengjiangcool@gmail.com Signed-off-by: Mark Brown

regmap: irq: Set lockdep class for hierarchical IRQ domains

2024-11-01T18:57:59Z

Lockdep gives a false positive splat as it can't distinguish the lock which is taken by different IRQ descriptors from different IRQ chips that are organized in a way of a hierarchy: ====================================================== WARNING: possible circular locking dependency detected 6.12.0-rc5-next-20241101-00148-g9fabf8160b53 #562 Tainted: G W ------------------------------------------------------ modprobe/141 is trying to acquire lock: ffff899446947868 (intel_soc_pmic_bxtwc:502:(&bxtwc_regmap_config)->lock){+.+.}-{4:4}, at: regmap_update_bits_base+0x33/0x90 but task is already holding lock: ffff899446947c68 (&d->lock){+.+.}-{4:4}, at: __setup_irq+0x682/0x790 which lock already depends on the new lock. -> #3 (&d->lock){+.+.}-{4:4}: -> #2 (&desc->request_mutex){+.+.}-{4:4}: -> #1 (ipclock){+.+.}-{4:4}: -> #0 (intel_soc_pmic_bxtwc:502:(&bxtwc_regmap_config)->lock){+.+.}-{4:4}: Chain exists of: intel_soc_pmic_bxtwc:502:(&bxtwc_regmap_config)->lock --> &desc->request_mutex --> &d->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&d->lock); lock(&desc->request_mutex); lock(&d->lock); lock(intel_soc_pmic_bxtwc:502:(&bxtwc_regmap_config)->lock); *** DEADLOCK *** 3 locks held by modprobe/141: #0: ffff8994419368f8 (&dev->mutex){....}-{4:4}, at: __driver_attach+0xf6/0x250 #1: ffff89944690b250 (&desc->request_mutex){+.+.}-{4:4}, at: __setup_irq+0x1a2/0x790 #2: ffff899446947c68 (&d->lock){+.+.}-{4:4}, at: __setup_irq+0x682/0x790 Set a lockdep class when we map the IRQ so that it doesn't warn about a lockdep bug that doesn't exist. Fixes: 4af8be67fd99 ("regmap: Convert regmap_irq to use irq_domain") Signed-off-by: Andy Shevchenko Link: https://patch.msgid.link/20241101165553.4055617-1-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown

regmap-irq: Consistently use memset32() in regmap_irq_thread()

2024-09-29T23:11:09Z

The commit 4d60cac951fd ("regmap-irq: Add no_status support") adds an additional branch into IRQ thread handler in regmap. It wisely chose to use memset32() as it might be optimised on some architectures and hence give a performance benefit. At the same time the old code continue using simple memset(). Update the old code to use memset32(). Signed-off-by: Andy Shevchenko Link: https://patch.msgid.link/20240925082726.620622-1-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown

regmap: Allow setting IRQ domain name suffix

2024-08-13T11:45:01Z

When multiple IRQ domains are created from the same device-tree node they will get the same name based on the device-tree path. This will cause a naming collision in debugFS when IRQ domain specific entries are created. The regmap-IRQ creates per instance IRQ domains. This will lead to a domain name conflict when a device which provides more than one interrupt line uses the regmap-IRQ. Add support for specifying an IRQ domain name suffix when creating a regmap-IRQ controller. Signed-off-by: Matti Vaittinen Link: https://patch.msgid.link/776bc4996969e5081bcf61b9bdb5517e537147a3.1723120028.git.mazziesaccount@gmail.com Signed-off-by: Mark Brown