From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966444AbcHEI35 (ORCPT ); Fri, 5 Aug 2016 04:29:57 -0400 Received: from mailout2.w1.samsung.com ([210.118.77.12]:19222 "EHLO mailout2.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934069AbcHEI3v (ORCPT ); Fri, 5 Aug 2016 04:29:51 -0400 X-AuditID: cbfec7f4-f796c6d000001486-21-57a44e7c1c9b Subject: Re: [PATCH] clk: prevent __of_clk_get_hw_from_provider() from returning NULL To: Masahiro Yamada References: <1468919039-23004-1-git-send-email-yamada.masahiro@socionext.com> <20160804205734.GA15690@codeaurora.org> Cc: Stephen Boyd , linux-clk@vger.kernel.org, Michael Turquette , linux-kernel@vger.kernel.org From: Sylwester Nawrocki Message-id: <792d2cb8-06bf-7406-b79a-06c16b977bd4@samsung.com> Date: Fri, 05 Aug 2016 10:29:39 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-version: 1.0 In-reply-to: <20160804205734.GA15690@codeaurora.org> Content-type: text/plain; charset=windows-1252 Content-transfer-encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrNLMWRmVeSWpSXmKPExsVy+t/xy7o1fkvCDd6v4rT42HOP1eLyrjls FhdPuVr8ONPNYrH33mdGB1aP9zda2T0u9/UyeZyY/p3F4/MmuQCWKC6blNSczLLUIn27BK6M tr+nmQr+slacXvOdpYHxDEsXIyeHhICJxLLdu9ghbDGJC/fWs3UxcnEICSxllNi08Ac7hPOc UeLLqheMIFXCAuESF7dMZQOxRQSMJT586WUGsYUEyiX+frzLAtLALNDPKLH16FcmkASbgKFE 79E+sGZeATuJDeuOgdksAqoSrY8ug9WICkRI3Fr1EapGUOLH5Htg53ECnTfnyhMgmwNoqJ7E /YtaIGFmAXmJzWveMk9gFJiFpGMWQtUsJFULGJlXMYqmliYXFCel5xrqFSfmFpfmpesl5+du YoQE8ZcdjIuPWR1iFOBgVOLhVYhdHC7EmlhWXJl7iFGCg1lJhPe+55JwId6UxMqq1KL8+KLS nNTiQ4zSHCxK4rxzd70PERJITyxJzU5NLUgtgskycXBKNTAG3JE+I/WtOm/2mZdrufeq9gtt MFx03lLx5tFfUwoPe+v7f3J5bb1Tdw3j71tb5hRzdP1km9H6r8T+8ZqC2RXmH754LOw/sPGa 0v8NPHmPE3N+yqzJLuL2k2OWZH8YIDZl+fFrrbvn/TFTl62pmCNozsl6UzZM1FrrVwa/2u46 o/4wyQPprglKLMUZiYZazEXFiQC2f7dKXgIAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/04/2016 10:57 PM, Stephen Boyd wrote: > On 07/19, Masahiro Yamada wrote: >> > The .get(_hw) callback of an OF clock provider can return a NULL >> > pointer in some cases. >> > >> > For example, of_clk_src_onecell_get() returns NULL for index 1 of a >> > sparse array of clocks like follows: >> > >> > clk_num == 3 >> > idx 0: UART clk >> > idx 1: NULL (no clk is allocated) >> > idx 2: I2C clk >> > >> > In such cases, clk_get() successfully returns NULL. I remember running into same issue before, we have addressed it by initializing the array of clocks with some errno value, e.g ERR_PTR(-ENOENT), so there is no chance to get NULL from the array - either a valid clk pointer or an ERR_PTR() value. -- Thanks, Sylwester