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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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+=============================
+Frame Buffer device internals
+=============================
+
+This is a first start for some documentation about frame buffer device
+internals.
+
+Authors:
+
+- Geert Uytterhoeven <geert@linux-m68k.org>, 21 July 1998
+- James Simmons <jsimmons@user.sf.net>, Nov 26 2002
+
+--------------------------------------------------------------------------------
+
+Structures used by the frame buffer device API
+==============================================
+
+The following structures play a role in the game of frame buffer devices. They
+are defined in <linux/fb.h>.
+
+1. Outside the kernel (user space)
+
+ - struct fb_fix_screeninfo
+
+ Device independent unchangeable information about a frame buffer device and
+ a specific video mode. This can be obtained using the FBIOGET_FSCREENINFO
+ ioctl.
+
+ - struct fb_var_screeninfo
+
+ Device independent changeable information about a frame buffer device and a
+ specific video mode. This can be obtained using the FBIOGET_VSCREENINFO
+ ioctl, and updated with the FBIOPUT_VSCREENINFO ioctl. If you want to pan
+ the screen only, you can use the FBIOPAN_DISPLAY ioctl.
+
+ - struct fb_cmap
+
+ Device independent colormap information. You can get and set the colormap
+ using the FBIOGETCMAP and FBIOPUTCMAP ioctls.
+
+
+2. Inside the kernel
+
+ - struct fb_info
+
+ Generic information, API and low level information about a specific frame
+ buffer device instance (slot number, board address, ...).
+
+ - struct `par`
+
+ Device dependent information that uniquely defines the video mode for this
+ particular piece of hardware.
+
+
+Visuals used by the frame buffer device API
+===========================================
+
+
+Monochrome (FB_VISUAL_MONO01 and FB_VISUAL_MONO10)
+--------------------------------------------------
+Each pixel is either black or white.
+
+
+Pseudo color (FB_VISUAL_PSEUDOCOLOR and FB_VISUAL_STATIC_PSEUDOCOLOR)
+---------------------------------------------------------------------
+The whole pixel value is fed through a programmable lookup table that has one
+color (including red, green, and blue intensities) for each possible pixel
+value, and that color is displayed.
+
+
+True color (FB_VISUAL_TRUECOLOR)
+--------------------------------
+The pixel value is broken up into red, green, and blue fields.
+
+
+Direct color (FB_VISUAL_DIRECTCOLOR)
+------------------------------------
+The pixel value is broken up into red, green, and blue fields, each of which
+are looked up in separate red, green, and blue lookup tables.
+
+
+Grayscale displays
+------------------
+Grayscale and static grayscale are special variants of pseudo color and static
+pseudo color, where the red, green and blue components are always equal to
+each other.