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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
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tree757a3d280760c654767631cab5ad8af2d86d1848 /Documentation/ABI/testing/sysfs-auxdisplay-linedisp
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Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
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+What: /sys/.../message
+Date: October 2021
+KernelVersion: 5.16
+Description:
+ Controls the text message displayed on character line displays.
+
+ Reading returns the current message with a trailing newline.
+ Writing updates the displayed message. Messages longer than the
+ display width will automatically scroll. Trailing newlines in
+ input are automatically trimmed.
+
+ Writing an empty string clears the display.
+
+ Example:
+ echo "Hello World" > message
+ cat message # Returns "Hello World\n"
+
+What: /sys/.../num_chars
+Date: November 2025
+KernelVersion: 6.18
+Contact: Jean-François Lessard <jefflessard3@gmail.com>
+Description:
+ Read-only attribute showing the character width capacity of
+ the line display device. Messages longer than this will scroll.
+
+ Example:
+ cat num_chars # Returns "16\n" for 16-char display
+
+What: /sys/.../scroll_step_ms
+Date: October 2021
+KernelVersion: 5.16
+Description:
+ Controls the scrolling speed for messages longer than the display
+ width, specified in milliseconds per scroll step.
+
+ Setting to 0 disables scrolling. Default is 500ms.
+
+ Example:
+ echo "250" > scroll_step_ms # 4Hz scrolling
+ cat scroll_step_ms # Returns "250\n"
+
+What: /sys/.../map_seg7
+Date: January 2024
+KernelVersion: 6.9
+Description:
+ Read/write binary blob representing the ASCII-to-7-segment
+ display conversion table used by the linedisp driver, as defined
+ by struct seg7_conversion_map in <linux/map_to_7segment.h>.
+
+ Only visible on displays with 7-segment capability.
+
+ This attribute is not human-readable. Writes must match the
+ struct size exactly, else -EINVAL is returned; reads return the
+ entire mapping as a binary blob.
+
+ This interface and its implementation match existing conventions
+ used in segment-mapped display drivers since 2005.
+
+ ABI note: This style of binary sysfs attribute *is an exception*
+ to current "one value per file, text only" sysfs rules, for
+ historical compatibility and driver uniformity. New drivers are
+ discouraged from introducing additional binary sysfs ABIs.
+
+ Reference interface guidance:
+ - include/uapi/linux/map_to_7segment.h
+
+What: /sys/.../map_seg14
+Date: January 2024
+KernelVersion: 6.9
+Description:
+ Read/write binary blob representing the ASCII-to-14-segment
+ display conversion table used by the linedisp driver, as defined
+ by struct seg14_conversion_map in <linux/map_to_14segment.h>.
+
+ Only visible on displays with 14-segment capability.
+
+ This attribute is not human-readable. Writes must match the
+ struct size exactly, else -EINVAL is returned; reads return the
+ entire mapping as a binary blob.
+
+ This interface and its implementation match existing conventions
+ used by segment-mapped display drivers since 2005.
+
+ ABI note: This style of binary sysfs attribute *is an exception*
+ to current "one value per file, text only" sysfs rules, for
+ historical compatibility and driver uniformity. New drivers are
+ discouraged from introducing additional binary sysfs ABIs.
+
+ Reference interface guidance:
+ - include/uapi/linux/map_to_14segment.h