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    SubjectRe: [Linux-fbdev-devel] Re: [PATCH] fbdev: colormap fixes
    I've verified now that all ATI R300+ chips have 10bit cmaps. These are
    pretty common so I'd be in favor of making this into a binary
    attribute where I can get/set the whole table at once. Given that
    OpenGL is already supporting 12 and 16 bits these tables are only
    going to get much larger.

    1024 entries * 5 fields * 2 bytes = 10KB -- too big for a text attribute.

    65536 entries * 5 fields * 2 bytes = 655KB -- way too big for a text attribute.

    The bits_per_pixel sysfs attribute is an easy way to tell how many
    entries you need. You can just set it at 4, 8, 10, etc until you get
    an error. Now you know the max. 2^n and you know how many entries.

    Jon Smirl
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