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authorYijie Yang <yijie.yang@oss.qualcomm.com>2026-08-11 16:46:47 +0800
committerRob Herring (Arm) <robh@kernel.org>2026-08-15 15:46:52 -0500
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dt-bindings: interconnect: qcom-bwmon: Add Maili cpu-bwmon compatiblegrafted
Add the Qualcomm Maili SoC compatible string for the CPU bandwidth monitor (BWMONv4). This falls back to the sdm845-bwmon compatible, consistent with the existing pattern used by other recent SoCs such as sm8750 and kaanapali. Signed-off-by: Yijie Yang <yijie.yang@oss.qualcomm.com> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com> Reviewed-by: Jingyi Wang <jingyi.wang@oss.qualcomm.com> Link: https://patch.msgid.link/20260811-bwmon-v2-1-80f7f150ab9e@oss.qualcomm.com Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
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+Linux Braille Console
+=====================
+
+To get early boot messages on a braille device (before userspace screen
+readers can start), you first need to compile the support for the usual serial
+console (see :ref:`Documentation/admin-guide/serial-console.rst <serial_console>`), and
+for braille device
+(in :menuselection:`Device Drivers --> Accessibility support --> Console on braille device`).
+
+Then you need to specify a ``console=brl``, option on the kernel command line, the
+format is::
+
+ console=brl,serial_options...
+
+where ``serial_options...`` are the same as described in
+:ref:`Documentation/admin-guide/serial-console.rst <serial_console>`.
+
+So for instance you can use ``console=brl,ttyS0`` if the braille device is connected to the first serial port, and ``console=brl,ttyS0,115200`` to
+override the baud rate to 115200, etc.
+
+By default, the braille device will just show the last kernel message (console
+mode). To review previous messages, press the Insert key to switch to the VT
+review mode. In review mode, the arrow keys permit to browse in the VT content,
+`PAGE-UP`/`PAGE-DOWN` keys go at the top/bottom of the screen, and
+the `HOME` key goes back
+to the cursor, hence providing very basic screen reviewing facility.
+
+Sound feedback can be obtained by adding the ``braille_console.sound=1`` kernel
+parameter.
+
+For simplicity, only one braille console can be enabled, other uses of
+``console=brl,...`` will be discarded. Also note that it does not interfere with
+the console selection mechanism described in
+:ref:`Documentation/admin-guide/serial-console.rst <serial_console>`.
+
+For now, only the VisioBraille device is supported.
+
+Samuel Thibault <samuel.thibault@ens-lyon.org>