From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933299AbaKSXQX (ORCPT ); Wed, 19 Nov 2014 18:16:23 -0500 Received: from mail-wg0-f47.google.com ([74.125.82.47]:59747 "EHLO mail-wg0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757180AbaKSXQP (ORCPT ); Wed, 19 Nov 2014 18:16:15 -0500 From: James Hogan To: Mike Turquette , linux-metag@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Cc: James Hogan , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala Subject: [PATCH 09/15] dt: binding: add binding for TZ1090 clock deleter Date: Wed, 19 Nov 2014 23:15:37 +0000 Message-Id: <1416438943-11429-10-git-send-email-james.hogan@imgtec.com> X-Mailer: git-send-email 2.0.4 In-Reply-To: <1416438943-11429-1-git-send-email-james.hogan@imgtec.com> References: <1416438943-11429-1-git-send-email-james.hogan@imgtec.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add DT binding for the clock deleters in the TZ1090 SoC, which delete up to 1023 out of every 1024 clock pulses of the input clock. Signed-off-by: James Hogan Cc: Mike Turquette Cc: Rob Herring Cc: Pawel Moll Cc: Mark Rutland Cc: Ian Campbell Cc: Kumar Gala Cc: linux-metag@vger.kernel.org Cc: devicetree@vger.kernel.org --- .../bindings/clock/img,tz1090-deleter.txt | 40 ++++++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 Documentation/devicetree/bindings/clock/img,tz1090-deleter.txt diff --git a/Documentation/devicetree/bindings/clock/img,tz1090-deleter.txt b/Documentation/devicetree/bindings/clock/img,tz1090-deleter.txt new file mode 100644 index 0000000..0f595be --- /dev/null +++ b/Documentation/devicetree/bindings/clock/img,tz1090-deleter.txt @@ -0,0 +1,40 @@ +Binding for TZ1090 clock deleter. + +This binding uses the common clock binding[1]. The TZ1090 clock deleters can be +configured to delete a certain fraction of the input clock pulses, so the output +frequency is: + + deleted_cycles = (reg & bit_mask) >> bit_shift + f_out = f_in * (cycle_period - deleted_cycles) / cycle_period + +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt + +Required properties: +- compatible : Shall be "img,tz1090-deleter". +- #clock-cells : From common clock binding; shall be set to 0. +- reg : Address of configuration register. +- bit-mask : Shift of config value field in configuration register. +- clocks : From common clock binding. + +Required source clocks: +- 0 : Reference clock which is deleted to produce the output + clock (doesn't have to be named). + +Optional properties: +- clock-output-names : From common clock binding. +- bit-shift : Number of bits to shift the bit-mask, defaults to + (ffs(mask) - 1) if not present. +- cycle-period : Period from which clocks are deleted, defaults to + (1 << (fls(mask) - bit-shift)) if not present. + +Example: + meta_clkdelete { + compatible = "img,tz1090-deleter"; + #clock-cells = <0>; + clocks = <&sys_clk_x2_undeleted>; + reg = <0x0200591c 0x4>; + bit-mask = <0x000003ff>; + /* implicit bit-shift = <0> */ + /* implicit cycle-period = <1024> */ + clock-output-names = "meta"; + }; -- 2.0.4