Message ID | 1481895135-11055-1-git-send-email-jean-christophe.trotin@st.com (mailing list archive) |
---|---|
State | Rejected, archived |
Delegated to: | Hans Verkuil |
Headers |
Received: from mail.tu-berlin.de ([130.149.7.33]) by www.linuxtv.org with esmtp (Exim 4.84_2) (envelope-from <linux-media-owner@vger.kernel.org>) id 1cHscw-0006Gc-Rl; Fri, 16 Dec 2016 13:32:46 +0000 X-tubIT-Incoming-IP: 209.132.180.67 Received: from vger.kernel.org ([209.132.180.67]) by mail.tu-berlin.de (exim-4.84_2/mailfrontend-6) with esmtp id 1cHsct-0003KA-4W; Fri, 16 Dec 2016 14:32:46 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757596AbcLPNcl (ORCPT <rfc822;mkrufky@linuxtv.org> + 1 other); Fri, 16 Dec 2016 08:32:41 -0500 Received: from mx08-00178001.pphosted.com ([91.207.212.93]:63172 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757498AbcLPNck (ORCPT <rfc822;linux-media@vger.kernel.org>); Fri, 16 Dec 2016 08:32:40 -0500 Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx08-00178001.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id uBGDVAtu004954; Fri, 16 Dec 2016 14:32:37 +0100 Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx08-.pphosted.com with ESMTP id 27bdmsydcc-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Fri, 16 Dec 2016 14:32:37 +0100 Received: from zeta.dmz-eu.st.com (zeta.dmz-eu.st.com [164.129.230.9]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 717FB31; Fri, 16 Dec 2016 13:32:36 +0000 (GMT) Received: from Webmail-eu.st.com (Safex1hubcas23.st.com [10.75.90.46]) by zeta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 5B5792BE4; Fri, 16 Dec 2016 13:32:36 +0000 (GMT) Received: from localhost (10.201.23.70) by webmail-ga.st.com (10.75.90.48) with Microsoft SMTP Server (TLS) id 14.3.294.0; Fri, 16 Dec 2016 14:32:36 +0100 From: Jean-Christophe Trotin <jean-christophe.trotin@st.com> To: <linux-media@vger.kernel.org>, Hans Verkuil <hverkuil@xs4all.nl> CC: <kernel@stlinux.com>, Benjamin Gaignard <benjamin.gaignard@linaro.org>, Yannick Fertre <yannick.fertre@st.com>, Hugues Fruchet <hugues.fruchet@st.com>, Jean-Christophe Trotin <jean-christophe.trotin@st.com> Subject: [PATCH v1] [media] v4l2-common: fix aligned value calculation Date: Fri, 16 Dec 2016 14:32:15 +0100 Message-ID: <1481895135-11055-1-git-send-email-jean-christophe.trotin@st.com> X-Mailer: git-send-email 1.9.1 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.201.23.70] X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2016-12-16_09:, , signatures=0 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: <linux-media.vger.kernel.org> X-Mailing-List: linux-media@vger.kernel.org X-PMX-Version: 6.0.0.2142326, Antispam-Engine: 2.7.2.2107409, Antispam-Data: 2016.12.16.132116 X-PMX-Spam: Gauge=IIIIIIIII, Probability=9%, Report=' MULTIPLE_RCPTS 0.1, HTML_00_01 0.05, HTML_00_10 0.05, MSGID_ADDED_BY_MTA 0.05, BODYTEXTP_SIZE_3000_LESS 0, BODY_SIZE_1000_1099 0, BODY_SIZE_2000_LESS 0, BODY_SIZE_5000_LESS 0, BODY_SIZE_7000_LESS 0, NO_URI_HTTPS 0, SINGLE_URI_IN_BODY 0, URI_ENDS_IN_HTML 0, WEBMAIL_SOURCE 0, WEBMAIL_XOIP 0, WEBMAIL_X_IP_HDR 0, __ANY_URI 0, __CC_NAME 0, __CC_NAME_DIFF_FROM_ACC 0, __CC_REAL_NAMES 0, __CP_URI_IN_BODY 0, __CT 0, __CT_TEXT_PLAIN 0, __HAS_CC_HDR 0, __HAS_FROM 0, __HAS_MSGID 0, __HAS_XOIP 0, __HAS_X_MAILER 0, __HAS_X_MAILING_LIST 0, __MIME_TEXT_ONLY 0, __MIME_TEXT_P 0, __MIME_TEXT_P1 0, __MIME_VERSION 0, __MULTIPLE_RCPTS_CC_X2 0, __NO_HTML_TAG_RAW 0, __SANE_MSGID 0, __SINGLE_URI_TEXT 0, __TO_MALFORMED_2 0, __TO_NAME 0, __TO_NAME_DIFF_FROM_ACC 0, __TO_NO_NAME 0, __TO_REAL_NAMES 0, __URI_IN_BODY 0, __URI_NO_WWW 0, __URI_NS , __URI_WITH_PATH 0' |
Commit Message
Jean-Christophe Trotin
Dec. 16, 2016, 1:32 p.m. UTC
Correct the calculation of the rounding to nearest aligned value in
the clamp_align() function. For example, clamp_align(1277, 1, 9600, 2)
returns 1276, while it should return 1280.
Signed-off-by: Jean-Christophe Trotin <jean-christophe.trotin@st.com>
---
drivers/media/v4l2-core/v4l2-common.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
Comments
Hi Jean-Christophe, On Fri, Dec 16, 2016 at 02:32:15PM +0100, Jean-Christophe Trotin wrote: > Correct the calculation of the rounding to nearest aligned value in > the clamp_align() function. For example, clamp_align(1277, 1, 9600, 2) > returns 1276, while it should return 1280. Why should the function return 1280 instead of 1276, which is closer to 1277? > > Signed-off-by: Jean-Christophe Trotin <jean-christophe.trotin@st.com> > --- > drivers/media/v4l2-core/v4l2-common.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c > index 57cfe26a..2970ce7 100644 > --- a/drivers/media/v4l2-core/v4l2-common.c > +++ b/drivers/media/v4l2-core/v4l2-common.c > @@ -315,7 +315,7 @@ static unsigned int clamp_align(unsigned int x, unsigned int min, > > /* Round to nearest aligned value */ > if (align) > - x = (x + (1 << (align - 1))) & mask; > + x = (x + ((1 << align) - 1)) & mask; > > return x; > }
Hi Sakari, Thank you for your answer. You're right: the modification that I proposed, is not correct (I misunderstood the aim of the function); the current clamp_align() is correct and doesn't need any modification. Thus, the patch that I sent, must be ignored. Sorry for the disruption. Regards, Jean-Christophe. On 12/16/2016 02:56 PM, Sakari Ailus wrote: > Hi Jean-Christophe, > > On Fri, Dec 16, 2016 at 02:32:15PM +0100, Jean-Christophe Trotin wrote: >> Correct the calculation of the rounding to nearest aligned value in >> the clamp_align() function. For example, clamp_align(1277, 1, 9600, 2) >> returns 1276, while it should return 1280. > > Why should the function return 1280 instead of 1276, which is closer to > 1277? > >> >> Signed-off-by: Jean-Christophe Trotin <jean-christophe.trotin@st.com> >> --- >> drivers/media/v4l2-core/v4l2-common.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c >> index 57cfe26a..2970ce7 100644 >> --- a/drivers/media/v4l2-core/v4l2-common.c >> +++ b/drivers/media/v4l2-core/v4l2-common.c >> @@ -315,7 +315,7 @@ static unsigned int clamp_align(unsigned int x, unsigned int min, >> >> /* Round to nearest aligned value */ >> if (align) >> - x = (x + (1 << (align - 1))) & mask; >> + x = (x + ((1 << align) - 1)) & mask; >> >> return x; >> } >-- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c index 57cfe26a..2970ce7 100644 --- a/drivers/media/v4l2-core/v4l2-common.c +++ b/drivers/media/v4l2-core/v4l2-common.c @@ -315,7 +315,7 @@ static unsigned int clamp_align(unsigned int x, unsigned int min, /* Round to nearest aligned value */ if (align) - x = (x + (1 << (align - 1))) & mask; + x = (x + ((1 << align) - 1)) & mask; return x; }