From: Michal Januszewski Date: Tue, 16 Oct 2007 08:28:26 +0000 (-0700) Subject: uvesafb: the driver core X-Git-Tag: v2.6.24-rc1~957 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8bdb3a2d7df48b861972c4bfb58490853a228f51;p=pandora-kernel.git uvesafb: the driver core uvesafb is an enhanced version of vesafb. It uses a userspace helper (v86d) to execute calls to the x86 Video BIOS functions. The driver is not limited to any specific arch and whether it works on a given arch or not depends on that arch being supported by the userspace daemon. It has been tested on x86_32 and x86_64. A single BIOS call is represented by an instance of the uvesafb_ktask structure. This structure contains a buffer, a completion struct and a uvesafb_task substructure, containing the values of the x86 registers, a flags field and a field indicating the length of the buffer. Whenever a BIOS call is made in the driver, uvesafb_exec() builds a message using the uvesafb_task substructure and the contents of the buffer. This message is then assigned a random ack number and sent to the userspace daemon using the connector interface. The message's sequence number is used as an index for the uvfb_tasks array, which provides a mapping from the messages coming from userspace to the in-kernel uvesafb_ktask structs. The userspace daemon performs the requested operation and sends a reply in the form of a uvesafb_task struct and, optionally, a buffer. The seq and ack numbers in the reply should be exactly the same as those in the request. Each message from userspace is processed by uvesafb_cn_callback() and after passing a few sanity checks leads to the completion of a BIOS call request. Signed-off-by: Michal Januszewski Signed-off-by: Antonino Daplas Cc: Paul Mundt Cc: Paulo Marques Cc: "H. Peter Anvin" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Reading git-diff-tree failed