From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751580AbdFGMeh (ORCPT ); Wed, 7 Jun 2017 08:34:37 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:39417 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751435AbdFGMeg (ORCPT ); Wed, 7 Jun 2017 08:34:36 -0400 Subject: Re: [PATCH 1/9] [media] s5p-jpeg: Reset the Codec before doing a soft reset To: Jacek Anaszewski , Andrzej Pietrasiewicz , Mauro Carvalho Chehab Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org References: <1496419376-17099-1-git-send-email-thierry.escande@collabora.com> <1496419376-17099-2-git-send-email-thierry.escande@collabora.com> <359e198e-df2b-ef47-17b9-cefe4b7ff220@gmail.com> From: Thierry Escande Message-ID: <4093ab04-710b-2141-ec16-62547fb4e66f@collabora.com> Date: Wed, 7 Jun 2017 14:34:31 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.1.1 MIME-Version: 1.0 In-Reply-To: <359e198e-df2b-ef47-17b9-cefe4b7ff220@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jacek, On 02/06/2017 21:50, Jacek Anaszewski wrote: > Hi Thierry, > > On 06/02/2017 06:02 PM, Thierry Escande wrote: >> From: Abhilash Kesavan >> >> This patch resets the encoding and decoding register bits before doing a >> soft reset. >> >> Signed-off-by: Tony K Nadackal >> Signed-off-by: Thierry Escande >> --- >> drivers/media/platform/s5p-jpeg/jpeg-hw-exynos4.c | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/drivers/media/platform/s5p-jpeg/jpeg-hw-exynos4.c b/drivers/media/platform/s5p-jpeg/jpeg-hw-exynos4.c >> index a1d823a..9ad8f6d 100644 >> --- a/drivers/media/platform/s5p-jpeg/jpeg-hw-exynos4.c >> +++ b/drivers/media/platform/s5p-jpeg/jpeg-hw-exynos4.c >> @@ -21,6 +21,10 @@ void exynos4_jpeg_sw_reset(void __iomem *base) >> unsigned int reg; >> >> reg = readl(base + EXYNOS4_JPEG_CNTL_REG); >> + writel(reg & ~(EXYNOS4_DEC_MODE | EXYNOS4_ENC_MODE), >> + base + EXYNOS4_JPEG_CNTL_REG); > > Why is it required? It would be nice if commit message explained that. Unfortunately the bug entry in the ChromeOS issue tracker does not mention more information about that and the patch author is no more reachable on that email address. So unless someone else knows the answer I won't be able to give more explanation in the commit message... Regards, Thierry