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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
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tree60a31895b2446cd7fa27514e8c2843534a0de0da /Documentation/ABI/testing/rtc-cdev
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Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
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+What: /dev/rtcX
+Date: April 2005
+KernelVersion: 2.6.12
+Contact: linux-rtc@vger.kernel.org
+Description:
+ The ioctl interface to drivers for real-time clocks (RTCs).
+ Following actions are supported:
+
+ * RTC_RD_TIME, RTC_SET_TIME: Read or set the RTC time. Time
+ format is a Gregorian calendar date and 24 hour wall clock
+ time.
+
+ * RTC_AIE_ON, RTC_AIE_OFF: Enable or disable the alarm interrupt
+ for RTCs that support alarms
+
+ * RTC_ALM_READ, RTC_ALM_SET: Read or set the alarm time for
+ RTCs that support alarms. Can be set up to 24 hours in the
+ future. Requires a separate RTC_AIE_ON call to enable the
+ alarm interrupt. (Prefer to use RTC_WKALM_*)
+
+ * RTC_WKALM_RD, RTC_WKALM_SET: For RTCs that support a more
+ powerful interface, which can issue alarms beyond 24 hours and
+ enable IRQs in the same request.
+
+ * RTC_PIE_ON, RTC_PIE_OFF: Enable or disable the periodic
+ interrupt for RTCs that support periodic interrupts.
+
+ * RTC_UIE_ON, RTC_UIE_OFF: Enable or disable the update
+ interrupt for RTCs that support it.
+
+ * RTC_IRQP_READ, RTC_IRQP_SET: Read or set the frequency for
+ periodic interrupts for RTCs that support periodic interrupts.
+ Requires a separate RTC_PIE_ON call to enable the periodic
+ interrupts.
+
+ * RTC_VL_READ: Read the voltage inputs status of the RTC when
+ supported. The value is a bit field of RTC_VL_*, giving the
+ status of the main and backup voltages.
+
+ * RTC_VL_CLEAR: Clear the voltage status of the RTC. Some RTCs
+ need user interaction when the backup power provider is
+ replaced or charged to be able to clear the status.
+
+ The ioctl() calls supported by the older /dev/rtc interface are
+ also supported by the newer RTC class framework. However,
+ because the chips and systems are not standardized, some PC/AT
+ functionality might not be provided. And in the same way, some
+ newer features -- including those enabled by ACPI -- are exposed
+ by the RTC class framework, but can't be supported by the older
+ driver.