From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomasz Figa Subject: Re: [RFC,v3 6/9] media: platform: Add Mediatek ISP P1 V4L2 functions Date: Mon, 5 Aug 2019 18:59:19 +0900 Message-ID: References: <20190611035344.29814-1-jungo.lin@mediatek.com> <20190611035344.29814-7-jungo.lin@mediatek.com> <20190710095429.GA181405@chromium.org> <1563424741.1212.212.camel@mtksdccf07> <1563942689.1212.494.camel@mtksdccf07> <1564363089.1212.636.camel@mtksdccf07> <1564451089.1212.649.camel@mtksdccf07> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1564451089.1212.649.camel@mtksdccf07> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+glpam-linux-mediatek=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org To: Jungo Lin Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, =?UTF-8?B?U2VhbiBDaGVuZyAo6YSt5piH5byYKQ==?= , Mauro Carvalho Chehab , =?UTF-8?B?UnlubiBXdSAo5ZCz6IKy5oGpKQ==?= , srv_heupstream , Rob Herring , =?UTF-8?B?UnlhbiBZdSAo5L2Z5a2f5L+uKQ==?= , =?UTF-8?B?RnJhbmtpZSBDaGl1ICjpgrHmloflh7Ep?= , Hans Verkuil , Matthias Brugger , Sj Huang , "moderated list:ARM/Mediatek SoC support" , Laurent Pinchart , ddavenport-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, =?UTF-8?B?RnJlZGVyaWMgQ2hlbiAo6Zmz5L+K5YWDKQ==?= , "list-Y9sIeH5OGRo@public.gmane.org:IOMMU DRIVERS , Joerg Roedel , " List-Id: devicetree@vger.kernel.org Hi Jungo, On Tue, Jul 30, 2019 at 10:45 AM Jungo Lin wrote: > > On Mon, 2019-07-29 at 19:04 +0900, Tomasz Figa wrote: > > On Mon, Jul 29, 2019 at 10:18 AM Jungo Lin wrote: > > > On Fri, 2019-07-26 at 14:49 +0900, Tomasz Figa wrote: > > > > On Wed, Jul 24, 2019 at 1:31 PM Jungo Lin wrote: > > > > > On Tue, 2019-07-23 at 19:21 +0900, Tomasz Figa wrote: > > > > > > On Thu, Jul 18, 2019 at 1:39 PM Jungo Lin wrote: > > > > > > > On Wed, 2019-07-10 at 18:54 +0900, Tomasz Figa wrote: > > > > > > > > On Tue, Jun 11, 2019 at 11:53:41AM +0800, Jungo Lin wrote: [snip] > > > > > > > > > + > > > > > > > > > + dev_dbg(dev, "%s: node:%d fd:%d idx:%d\n", > > > > > > > > > + __func__, > > > > > > > > > + node->id, > > > > > > > > > + buf->vbb.request_fd, > > > > > > > > > + buf->vbb.vb2_buf.index); > > > > > > > > > + > > > > > > > > > + /* For request buffers en-queue, handled in mtk_cam_req_try_queue */ > > > > > > > > > + if (vb->vb2_queue->uses_requests) > > > > > > > > > + return; > > > > > > > > > > > > > > > > I'd suggest removing non-request support from this driver. Even if we end up > > > > > > > > with a need to provide compatibility for non-request mode, then it should be > > > > > > > > built on top of the requests mode, so that the driver itself doesn't have to > > > > > > > > deal with two modes. > > > > > > > > > > > > > > > > > > > > > > The purpose of non-request function in this driver is needed by > > > > > > > our camera middle-ware design. It needs 3A statistics buffers before > > > > > > > image buffers en-queue. So we need to en-queue 3A statistics with > > > > > > > non-request mode in this driver. After MW got the 3A statistics data, it > > > > > > > will en-queue the images, tuning buffer and other meta buffers with > > > > > > > request mode. Based on this requirement, do you have any suggestion? > > > > > > > For upstream driver, should we only consider request mode? > > > > > > > > > > > > > > > > > > > Where does that requirement come from? Why the timing of queuing of > > > > > > the buffers to the driver is important? > > > > > > > > > > > > [snip] > > > > > > > > > > Basically, this requirement comes from our internal camera > > > > > middle-ware/3A hal in user space. Since this is not generic requirement, > > > > > we will follow your original suggestion to keep the request mode only > > > > > and remove other non-request design in other files. For upstream driver, > > > > > it should support request mode only. > > > > > > > > > > > > > Note that Chromium OS will use the "upstream driver" and we don't want > > > > to diverge, so please make the userspace also use only requests. I > > > > don't see a reason why there would be any need to submit any buffers > > > > outside of a request. > > > > > > > > [snip] > > > > > > Ok, I have raised your concern to our colleagues and let him to discuss > > > with you in another communication channel. > > > > > > > Thanks! > > > > Best regards, > > Tomasz > > Our colleague is preparing material to explain the our 3A/MW design. If > he is ready, he will discuss this with you. Thanks! > > In the original plan, we will deliver P1 v4 patch set tomorrow (31th > Jul.). But, there are some comments waiting for other experts' input. > Do you suggest it is better to resolve all comments before v4 patch set > submitting or continue to discuss these comments on v4? For the remaining v4l2-compliance issues, we can postpone them and keep on a TODO list in the next version. Best regards, Tomasz