From mboxrd@z Thu Jan 1 00:00:00 1970 From: viresh.kumar@st.com (Viresh Kumar) Date: Tue, 17 Jan 2012 14:45:31 +0530 Subject: [PATCH 8/8] dmaengine/dw_dmac: Add support for DMA_SLAVE_CONFIG In-Reply-To: References: <7c1e6fd573d5cd348b22f8363c9960fe5efcd658.1326707233.git.viresh.kumar@st.com> <4F140D25.1000309@st.com> Message-ID: <4F153C33.5060805@st.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 1/17/2012 2:19 PM, Linus Walleij wrote: > Are you looking for ffs() from ? > > find-first-set (the include boils down to include/asm-generic/bitops/ffs.h > if you want to check the implementation). Thanks, but it might not solve the issue. :( Actually this will retain the first Least Significant Bit (which is 1) and will mark all other zero. So it will give output 0b10 for 0b110 >>> >> + * Fix sconfig's burst size according to dw_dmac. We need to convert >>> >> + * them as: 1 -> 0, 2 -> 1, 4 -> 2, 8 -> 3, 16 -> 4. I need above conversion. i.e. finding bit no. of first bit set. -- viresh From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752654Ab2AQJQL (ORCPT ); Tue, 17 Jan 2012 04:16:11 -0500 Received: from eu1sys200aog107.obsmtp.com ([207.126.144.123]:37006 "EHLO eu1sys200aog107.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750839Ab2AQJQJ (ORCPT ); Tue, 17 Jan 2012 04:16:09 -0500 Message-ID: <4F153C33.5060805@st.com> Date: Tue, 17 Jan 2012 14:45:31 +0530 From: Viresh Kumar User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:6.0) Gecko/20110812 Thunderbird/6.0 MIME-Version: 1.0 To: Linus Walleij Cc: "vinod.koul@intel.com" , "dan.j.williams@intel.com" , "linux@arm.linux.org.uk" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , Armando VISCONTI , Shiraz HASHIM , Vipin KUMAR , Rajeev KUMAR , Deepak SIKRI , Vipul Kumar SAMAR , Amit VIRDI , Pratyush ANAND , Bhupesh SHARMA , "viresh.linux@gmail.com" , Bhavna YADAV , Vincenzo FRASCINO , Mirko GARDI Subject: Re: [PATCH 8/8] dmaengine/dw_dmac: Add support for DMA_SLAVE_CONFIG References: <7c1e6fd573d5cd348b22f8363c9960fe5efcd658.1326707233.git.viresh.kumar@st.com> <4F140D25.1000309@st.com> In-Reply-To: Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 1/17/2012 2:19 PM, Linus Walleij wrote: > Are you looking for ffs() from ? > > find-first-set (the include boils down to include/asm-generic/bitops/ffs.h > if you want to check the implementation). Thanks, but it might not solve the issue. :( Actually this will retain the first Least Significant Bit (which is 1) and will mark all other zero. So it will give output 0b10 for 0b110 >>> >> + * Fix sconfig's burst size according to dw_dmac. We need to convert >>> >> + * them as: 1 -> 0, 2 -> 1, 4 -> 2, 8 -> 3, 16 -> 4. I need above conversion. i.e. finding bit no. of first bit set. -- viresh