[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <1351702333-8456-8-git-send-email-panto@antoniou-consulting.com>
Date: Wed, 31 Oct 2012 18:52:13 +0200
From: Pantelis Antoniou <panto@...oniou-consulting.com>
To: Tony Lindgren <tony@...mide.com>
Cc: Pantelis Antoniou <panto@...oniou-consulting.com>,
linux-arm-kernel@...ts.infradead.org,
devicetree-discuss@...ts.ozlabs.org, linux-kernel@...r.kernel.org,
Koen Kooi <koen@...inion.thruhere.net>,
Matt Porter <mporter@...com>, Russ Dill <Russ.Dill@...com>,
linux-omap@...r.kernel.org
Subject: [RFC 7/7] capebus: Documentation; capebus-summary
Small summary of capebus.
Signed-off-by: Pantelis Antoniou <panto@...oniou-consulting.com>
---
Documentation/capebus/capebus-summary | 40 +++++++++++++++++++++++++++++++++++
1 file changed, 40 insertions(+)
create mode 100644 Documentation/capebus/capebus-summary
diff --git a/Documentation/capebus/capebus-summary b/Documentation/capebus/capebus-summary
new file mode 100644
index 0000000..742e33c
--- /dev/null
+++ b/Documentation/capebus/capebus-summary
@@ -0,0 +1,40 @@
+Overview of Linux kernel Capebus support
+========================================
+
+30-Oct-2012
+
+What is Capebus?
+----------------
+Capebus is an abstract concept. There's no such thing as a vanilla physical
+capebus, what is there is a concept and a method on how various capebus
+based implementations can be made.
+
+Capebus is created to address the problem of many SoCs that can provide a
+multitude of hardware interfaces but in order to keep costs down the main
+boards only support a limited number of them. The rest are typically brought
+out to pin connectors on to which other boards, named capes are connected and
+allow those peripherals to be used.
+
+These capes connect to the SoC interfaces but might also contain various other
+parts that may need some kind of driver to work.
+
+Since SoCs have limited pins and pin muxing options, not all capes can work
+together so some kind of resource tracking (at least for the pins in use) is
+required.
+
+Before capebus all of this took place in the board support file, and frankly
+for boards with too many capes it was becoming unmanageable.
+
+Capebus provides a virtual bus, which along with a board specific controller,
+cape drivers can be written using the standard Linux device model.
+
+What kind of systems/boards capebus supports?
+---------------------------------------------
+
+The core capebus infrastructure is not depended on any specific board.
+However capebus needs a board controller to provide services to the cape devices
+it controls. Services like addressing and resource reservation are provided
+by the board controller.
+
+Capebus at the moment only support TI's Beaglebone platform.
+
--
1.7.12
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists