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authorMauro Carvalho Chehab <mchehab+samsung@kernel.org>2019-06-12 20:52:45 +0300
committerJonathan Corbet <corbet@lwn.net>2019-06-14 23:21:11 +0300
commitab42b818954c040fa13639dc031d8541edcecb4b (patch)
treebaf9142b53b039fa58ca66af479156f4886c9cc8 /Documentation/fb/arkfb.rst
parent10ffebbed5503b1830c7920ef528075785351be6 (diff)
downloadlinux-ab42b818954c040fa13639dc031d8541edcecb4b.tar.xz
docs: fb: convert docs to ReST and rename to *.rst
The conversion is actually: - add blank lines and identation in order to identify paragraphs; - fix tables markups; - add some lists markups; - mark literal blocks; - adjust title markups. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Also, removed the Maintained by, as requested by Geert. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
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+========================================
+arkfb - fbdev driver for ARK Logic chips
+========================================
+
+
+Supported Hardware
+==================
+
+ ARK 2000PV chip
+ ICS 5342 ramdac
+
+ - only BIOS initialized VGA devices supported
+ - probably not working on big endian
+
+
+Supported Features
+==================
+
+ * 4 bpp pseudocolor modes (with 18bit palette, two variants)
+ * 8 bpp pseudocolor mode (with 18bit palette)
+ * 16 bpp truecolor modes (RGB 555 and RGB 565)
+ * 24 bpp truecolor mode (RGB 888)
+ * 32 bpp truecolor mode (RGB 888)
+ * text mode (activated by bpp = 0)
+ * doublescan mode variant (not available in text mode)
+ * panning in both directions
+ * suspend/resume support
+
+Text mode is supported even in higher resolutions, but there is limitation to
+lower pixclocks (i got maximum about 70 MHz, it is dependent on specific
+hardware). This limitation is not enforced by driver. Text mode supports 8bit
+wide fonts only (hardware limitation) and 16bit tall fonts (driver
+limitation). Unfortunately character attributes (like color) in text mode are
+broken for unknown reason, so its usefulness is limited.
+
+There are two 4 bpp modes. First mode (selected if nonstd == 0) is mode with
+packed pixels, high nibble first. Second mode (selected if nonstd == 1) is mode
+with interleaved planes (1 byte interleave), MSB first. Both modes support
+8bit wide fonts only (driver limitation).
+
+Suspend/resume works on systems that initialize video card during resume and
+if device is active (for example used by fbcon).
+
+
+Missing Features
+================
+(alias TODO list)
+
+ * secondary (not initialized by BIOS) device support
+ * big endian support
+ * DPMS support
+ * MMIO support
+ * interlaced mode variant
+ * support for fontwidths != 8 in 4 bpp modes
+ * support for fontheight != 16 in text mode
+ * hardware cursor
+ * vsync synchronization
+ * feature connector support
+ * acceleration support (8514-like 2D)
+
+
+Known bugs
+==========
+
+ * character attributes (and cursor) in text mode are broken
+
+--
+Ondrej Zajicek <santiago@crfreenet.org>