From patchwork Mon Aug 18 16:56:54 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nishanth Menon X-Patchwork-Id: 4737981 Return-Path: X-Original-To: patchwork-linux-omap@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 41ADE9F3EE for ; Mon, 18 Aug 2014 16:58:38 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7B27D2015D for ; Mon, 18 Aug 2014 16:58:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 86E4720136 for ; Mon, 18 Aug 2014 16:58:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751745AbaHRQ5V (ORCPT ); Mon, 18 Aug 2014 12:57:21 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:56615 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751652AbaHRQ5U (ORCPT ); Mon, 18 Aug 2014 12:57:20 -0400 Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by comal.ext.ti.com (8.13.7/8.13.7) with ESMTP id s7IGuu9C006691; Mon, 18 Aug 2014 11:56:56 -0500 Received: from DFLE73.ent.ti.com (dfle73.ent.ti.com [128.247.5.110]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id s7IGuuWj021557; Mon, 18 Aug 2014 11:56:56 -0500 Received: from dlep33.itg.ti.com (157.170.170.75) by DFLE73.ent.ti.com (128.247.5.110) with Microsoft SMTP Server id 14.3.174.1; Mon, 18 Aug 2014 11:56:56 -0500 Received: from localhost (ileax41-snat.itg.ti.com [10.172.224.153]) by dlep33.itg.ti.com (8.14.3/8.13.8) with ESMTP id s7IGuuc9019678; Mon, 18 Aug 2014 11:56:56 -0500 From: Nishanth Menon To: Tero Kristo , Mike Turquette CC: , , , Nishanth Menon Subject: [PATCH 1/2] clk: ti: divider: Provide error check for incoming parameters in set_rate Date: Mon, 18 Aug 2014 11:56:54 -0500 Message-ID: <1408381015-16042-2-git-send-email-nm@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1408381015-16042-1-git-send-email-nm@ti.com> References: <1408381015-16042-1-git-send-email-nm@ti.com> MIME-Version: 1.0 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org X-Spam-Status: No, score=-7.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Check for valid parameters in check rate. Else, we end up getting errors like: [ 0.000000] Division by zero in kernel. [ 0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.17.0-rc1 #1 [ 0.000000] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [ 0.000000] [] (show_stack) from [] (dump_stack+0x78/0x94) [ 0.000000] [] (dump_stack) from [] (Ldiv0+0x8/0x10) [ 0.000000] [] (Ldiv0) from [] (ti_clk_divider_set_rate+0x14/0x14c) [ 0.000000] [] (ti_clk_divider_set_rate) from [] (clk_change_rate+0x138/0x180) [ 0.000000] [] (clk_change_rate) from [] (clk_change_rate+0x108/0x180) This occurs as part of the inital clock tree update of child clock nodes where new_rate could be 0 for non functional clocks. Fixes: b4761198bfaf296 ("CLK: ti: add support for ti divider-clock") Signed-off-by: Nishanth Menon --- drivers/clk/ti/divider.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/clk/ti/divider.c b/drivers/clk/ti/divider.c index e6aa10d..a837f70 100644 --- a/drivers/clk/ti/divider.c +++ b/drivers/clk/ti/divider.c @@ -211,11 +211,16 @@ static long ti_clk_divider_round_rate(struct clk_hw *hw, unsigned long rate, static int ti_clk_divider_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { - struct clk_divider *divider = to_clk_divider(hw); + struct clk_divider *divider; unsigned int div, value; unsigned long flags = 0; u32 val; + if (!hw || !rate) + return -EINVAL; + + divider = to_clk_divider(hw); + div = DIV_ROUND_UP(parent_rate, rate); value = _get_val(divider, div);