From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752586AbeAFSUX (ORCPT + 1 other); Sat, 6 Jan 2018 13:20:23 -0500 Received: from vern.gendns.com ([206.190.152.46]:60678 "EHLO vern.gendns.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750849AbeAFSUW (ORCPT ); Sat, 6 Jan 2018 13:20:22 -0500 From: David Lechner To: linux-clk@vger.kernel.org Cc: David Lechner , Michael Turquette , Stephen Boyd , linux-kernel@vger.kernel.org Subject: [PATCH] clk: divider: fix clk_round_rate() when CLK_DIVIDER_READ_ONLY && CLK_RATE_SET_PARENT Date: Sat, 6 Jan 2018 12:19:29 -0600 Message-Id: <1515262769-22665-1-git-send-email-david@lechnology.com> X-Mailer: git-send-email 2.7.4 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - vern.gendns.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - lechnology.com X-Get-Message-Sender-Via: vern.gendns.com: authenticated_id: davidmain+lechnology.com/only user confirmed/virtual account not confirmed X-Authenticated-Sender: vern.gendns.com: davidmain@lechnology.com X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: clk_round_rate() 'answers the question "if I were to pass @rate to clk_set_rate(), what clock rate would I end up with?" without changing the hardware'. Currently, clk_divider_round_rate() returns the "current value" when divider->flags & CLK_DIVIDER_READ_ONLY. But, if CLK_SET_RATE_PARENT is set, then clk_set_rate() is supposed to propagate the rate change to the parent clock. So, we need to do check for CLK_SET_RATE_PARENT and if it is set, ask the parent clock what rate it can provide given the current divider value. Signed-off-by: David Lechner --- drivers/clk/clk-divider.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c index 4ed516c..cffe9ef 100644 --- a/drivers/clk/clk-divider.c +++ b/drivers/clk/clk-divider.c @@ -357,6 +357,13 @@ static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate, bestdiv &= div_mask(divider->width); bestdiv = _get_div(divider->table, bestdiv, divider->flags, divider->width); + + if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) { + struct clk_hw *parent = clk_hw_get_parent(hw); + + *prate = clk_hw_round_rate(parent, rate * bestdiv); + } + return DIV_ROUND_UP_ULL((u64)*prate, bestdiv); } -- 2.7.4