laptop-kernel/drivers/rtc, branch master

rtc: spear: initialize IRQ state before requesting alarm IRQ

2026-09-21T20:46:42Z

devm_request_irq() enables the interrupt before it returns, so the handler may run while probe is still initializing the device. Initialize the MMIO address and spinlock before requesting the alarm IRQ. Fixes: 0942a71e435f ("rtc: add support for spear rtc") Cc: stable@vger.kernel.org Assisted-by: Codex:GPT-5 Signed-off-by: Runyu Xiao Link: https://patch.msgid.link/20260902080318.3498434-1-runyu.xiao@seu.edu.cn Signed-off-by: Alexandre Belloni

rtc: mpfs: fix unchecked devm_clk_get() error pointer in probe()

2026-09-21T19:28:17Z

devm_clk_get(&pdev->dev, "rtcref")'s return value was passed straight into clk_get_rate() without checking it for an error first, unlike the "rtc" clock a few lines above which is correctly checked with IS_ERR(). clk_get_rate() only guards against a NULL clk, not an error pointer: if (!clk) return 0; ... rate = clk_core_get_rate_recalc(clk->core); so if devm_clk_get() ever returns an error pointer here (for example ERR_PTR(-EPROBE_DEFER), which is the normal, expected outcome if the clkcfg clock-provider this RTC depends on has not registered its clocks yet by the time this driver probes), clk_get_rate() dereferences that error pointer instead of returning 0, crashing instead of letting probe defer. Capture the clock in the existing 'clk' local and check it with IS_ERR() before calling clk_get_rate(), matching the handling already used for the "rtc" clock in this same function. Signed-off-by: Manush Prajwal Fixes: 0b31d703598d ("rtc: Add driver for Microchip PolarFire SoC") Reviewed-by: Conor Dooley Link: https://patch.msgid.link/6a9d4b02.7d74b517.206c4c.75f8@mx.google.com Signed-off-by: Alexandre Belloni

rtc: ac100: Fix clock provider use-after-free on probe failure

2026-09-21T19:26:40Z

ac100_rtc_register_clks() registers the RTC-32k clock with clk_hw_register_fixed_rate() and the clock provider with of_clk_add_hw_provider(). Neither is device managed, and both are released only from ac100_rtc_remove(). The driver core does not call remove() when probe() fails: really_probe() reaches probe_failed below the device_remove() call and goes straight to releasing the device's managed resources. ac100_rtc_probe() ends with return devm_rtc_register_device(chip->rtc); so if that fails after the clocks have been registered, the provider is left on the global of_clk_providers list holding chip->clk_data, which was allocated with devm_kzalloc() and is freed while probe() unwinds. A later lookup on this device tree node then reads freed memory in of_clk_hw_onecell_get(). Consumers that do exactly that exist in tree: the wifi power sequence nodes on sun8i-a83t-bananapi-m3 and sun8i-a83t-cubietruck-plus take <&ac100_rtc 1>, and the sun9i-a80 boards route osc32k through <&ac100_rtc 0>. The window is narrow, as devm_rtc_register_device() can only fail with -ENOMEM here, but the provider is left dangling whenever it does. The RTC-32k clock is leaked on the same path. Since clk_core_lookup() searches a global list that is not scoped per device, __clk_register() rejects the duplicate name with -EEXIST, so the leak also makes a later probe of the same device fail. The error path that returns -EINVAL when the ADDA 4M parent clock cannot be found leaks the RTC-32k clock in the same way. No provider has been registered at that point, so that one is a leak rather than a use-after-free. Register both with devm_clk_hw_register_fixed_rate() and devm_of_clk_add_hw_provider() so that they are released whenever the device goes away, on a failed probe as well as on unbind. Devres releases in reverse order of acquisition, so the provider is removed before chip->clk_data is freed, and the clkout children are now unregistered before their parent rather than after it. ac100_rtc_unregister_clks() and the remove callback then have nothing left to do and are removed. Fixes: d00a18a42c14 ("rtc: ac100: Add RTC driver for X-Powers AC100") Reported-by: Sashiko AI Closes: https://lore.kernel.org/linux-rtc/20260905184936.155E11F00A3A@smtp.kernel.org/ Assisted-by: LLM Signed-off-by: Aamir Ahmed Link: https://patch.msgid.link/AS8P251MB0001A489CC45A591ABBB9BDCC8B42@AS8P251MB0001.EURP251.PROD.OUTLOOK.COM Signed-off-by: Alexandre Belloni

rtc: ac100: Assign .num before accessing .hws

2026-09-21T19:23:44Z

Commit f316cdff8d67 ("clk: Annotate struct clk_hw_onecell_data with __counted_by") annotated the hws member of 'struct clk_hw_onecell_data' with __counted_by, which informs the bounds sanitizer (UBSAN_BOUNDS) about the number of elements in .hws[], so that it can warn when .hws[] is accessed out of bounds. As noted in that change, the __counted_by member must be initialized with the number of elements before the first array access happens, otherwise there will be a warning from each access prior to the initialization because the number of elements is zero. This occurs in ac100_rtc_register_clks() due to .num being assigned only after every clkout clock has been stored in .hws[]. With CONFIG_UBSAN_BOUNDS and a compiler that implements __counted_by (GCC 15.1+ or Clang 20.1+), this triggers an array-index-out-of-bounds report during probe, and with CONFIG_UBSAN_TRAP the first store traps. Initialize .num with AC100_CLKOUT_NUM, the number of elements .hws[] was allocated with, right after the allocation. That is the value the loop counter ends up at on the success path anyway, so the provider's behaviour is unchanged. Cc: stable@vger.kernel.org Fixes: f316cdff8d67 ("clk: Annotate struct clk_hw_onecell_data with __counted_by") Assisted-by: LLM Signed-off-by: Aamir Ahmed Reviewed-by: Chen-Yu Tsai Reviewed-by: Gustavo A. R. Silva Link: https://patch.msgid.link/AS8P251MB00013E724A77A355668B6CCEC8B42@AS8P251MB0001.EURP251.PROD.OUTLOOK.COM Signed-off-by: Alexandre Belloni

rtc: efi: restore alarm support with runtime capability probe

2026-09-21T19:13:42Z

Restore the EFI RTC alarm functionality (read_alarm/set_alarm and procfs output) that was removed by commit 18a3510bc87d ("rtc: efi: Remove wakeup functionality"). The removal was motivated by the observation that many EFI platforms lack RTC wakeup support while also omitting the RT_PROP table, causing the wakeup capability to be incorrectly advertised. While that is true, removing the feature entirely also breaks platforms where the wakeup runtime service actually works. On CIX SoCs, the RTC is an I2C device owned by firmware, and in the ACPI boot configuration the I2C bus it sits on is not exposed to the OS, so the EFI runtime services are the only way Linux can access the RTC at all. Both Linux and Windows use this same interface by design, so the RTC state is consistent across the operating systems installed on the machine, and Windows relies on the EFI wakeup services for its own RTC alarm support. With the alarm support removed from rtc-efi, Linux loses the equivalent capability entirely on these platforms: rtcwake fails for both suspend-to-RAM and power-off wakeup, as there is no other path to program the RTC alarm. This is a real product requirement that CIX customers have explicitly requested, not a hypothetical use case. To avoid exposing a broken alarm on firmware that does not implement the wakeup runtime services, probe the capability at ->probe() time by actually calling GetWakeupTime() -- if it fails, clear RTC_FEATURE_ALARM and the device behaves as before the removal. Also set RTC_FEATURE_ALARM_WAKEUP_ONLY since EFI wakeup time is a wakeup-only alarm, not a periodic/update interrupt source. Acked-by: Ard Biesheuvel Reviewed-by: Feng Tang Reviewed-by: Fugang Duan Signed-off-by: Johnny.Fan Link: https://patch.msgid.link/20260831140014.839222-1-johnny.fan@cixtech.com Signed-off-by: Alexandre Belloni

rtc: dev: zero-initialize struct rtc_wkalrm to prevent information leak

2026-09-21T19:12:35Z

The struct rtc_wkalrm has padding holes after the 'pending' member. When returned to userspace via the RTC_WKALRM_RD ioctl, uninitialized kernel stack data residing in these holes may be leaked. Zero-initialize the struct at declaration to eliminate this information leak risk. Fixes smatch warnings: - drivers/rtc/dev.c:392 rtc_dev_ioctl() warn: check that 'alarm' doesn't leak information (struct has a hole after 'pending') Fixes: 36e14f5fdfdf ("rtc: rename core files") Assisted-by: smatch:2.0 [static analysis] Signed-off-by: Liu Dalin Link: https://patch.msgid.link/B28B7DE18F3A9447+20260827015444.3314227-1-liudalin@kylinsec.com.cn Signed-off-by: Alexandre Belloni

Merge tag 'rtc-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

2026-08-28T16:53:43Z

Pull RTC updates from Alexandre Belloni: "The RZN1 driver got a fairly comprehensive cleanup. More DT binding are converted to DT schema, leaving only 5 remaining files to convert. Subsystem: - patchwork project is moving to kernel.org - fully initialize clk_init_data - add missing MODULE_DEVICE_TABLE() - DT bindings conversions to DT schema Drivers: - ds1307: fix WADA bit for alarms on RX8130 - rzn1: add support for RZ/T2H and RZ/N2H, many fixes" * tag 'rtc-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (42 commits) MAINTAINERS: update rtc subsystem patchwork location rtc: msc313: Select by default on MSTARV7 rtc: microcrystal: Make sure clk_init_data is fully initialized rtc: philips: Make sure clk_init_data is fully initialized rtc: nct3018y: Make sure clk_init_data is fully initialized rtc: m41t80: Make sure clk_init_data is fully initialized rtc: hym8563: Make sure clk_init_data is fully initialized rtc: rzn1: Add support for Renesas RZ/T2H and RZ/N2H SoCs rtc: rzn1: Drop trailing comma from OF match table sentinel rtc: rzn1: Add OF match data to gate SUBU register access rtc: rzn1: use FIELD_PREP/FIELD_GET and GENMASK for register access rtc: rzn1: Consistently use dev_err_probe() rtc: rzn1: Use temporary variable for struct device rtc: rzn1: Dynamically calculate synchronization delay based on clock rate rtc: rzn1: Replace remove callback with devm_add_action_or_reset() rtc: rzn1: Use pm_runtime_put_sync() rtc: Kconfig: Broaden RTC_DRV_RZN1 dependency to ARCH_RENESAS rtc: rzn1: Fix malformed MODULE_AUTHOR string rtc: rzn1: Disable alarm interrupt before reprogramming alarm registers rtc: rzn1: Fix alarm range check truncation on 32-bit systems ...

rtc: msc313: Select by default on MSTARV7

2026-08-24T12:56:17Z

All of the ARCH_MSTARV7 chips have this RTC so it's more likely ARCH_MSTARV7 wants it than doesn't. At the same time fix up the indent on the depends on line that looks like it got converted from a tab to spaces at some point. Signed-off-by: Daniel Palmer Link: https://patch.msgid.link/20260713133919.1356748-1-daniel@thingy.jp Signed-off-by: Alexandre Belloni

rtc: microcrystal: Make sure clk_init_data is fully initialized

2026-08-23T19:49:51Z

The clk_init_data structure contains several mutually-exclusive members for different methods to specify the possible parents of a clock, prompting drivers to initialize only the members they need. However, not initializing all members may cause subtle issues, which are only exposed when CONFIG_INIT_STACK_ALL_PATTERN or CONFIG_INIT_STACK_NONE is enabled. Make sure all members are fully initialized, to avoid such bugs, and to prevent future breakage when converting drivers to a different method for specifying the parents. Signed-off-by: Geert Uytterhoeven Link: https://patch.msgid.link/6e7b5258ff73e93fe23dd83cf56f806ee60fa7a9.1787241693.git.geert+renesas@glider.be Signed-off-by: Alexandre Belloni

rtc: philips: Make sure clk_init_data is fully initialized

2026-08-23T19:49:51Z

The clk_init_data structure contains several mutually-exclusive members for different methods to specify the possible parents of a clock, prompting drivers to initialize only the members they need. However, not initializing all members may cause subtle issues, which are only exposed when CONFIG_INIT_STACK_ALL_PATTERN or CONFIG_INIT_STACK_NONE is enabled. Make sure all members are fully initialized, to avoid such bugs, and to prevent future breakage when converting drivers to a different method for specifying the parents. Signed-off-by: Geert Uytterhoeven Link: https://patch.msgid.link/8281eaf605069aac2211d83233e11285b8e8ca84.1787241693.git.geert+renesas@glider.be Signed-off-by: Alexandre Belloni