From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 53F4EC43612 for ; Wed, 9 Jan 2019 00:13:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2093720883 for ; Wed, 9 Jan 2019 00:13:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="qeWwZJ4S" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729100AbfAIAN6 (ORCPT ); Tue, 8 Jan 2019 19:13:58 -0500 Received: from perceval.ideasonboard.com ([213.167.242.64]:41670 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727917AbfAIAN6 (ORCPT ); Tue, 8 Jan 2019 19:13:58 -0500 Received: from avalon.localnet (dfj612ybrt5fhg77mgycy-3.rev.dnainternet.fi [IPv6:2001:14ba:21f5:5b00:2e86:4862:ef6a:2804]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 5EDDA586; Wed, 9 Jan 2019 01:13:55 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1546992835; bh=AkbaQOxZMi9tm3sFg5IQOR9ZFyELl2xqpYQHngZEugM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qeWwZJ4Sbo4rROc5VWCNZZ7KENPvaRbpOEqDuV0a5Zx6ZlkcaLCXUkeLDyq8mQ+Hn XHfoxNy5O2F8MxgsOzoBTBqSzderoi2qKqomr60fGRsaFial41h74HVfdphcvZXpaC HmChPIyF3/YS8gNI8CUzutWqK4PTjqY3l2zU3QIw= From: Laurent Pinchart To: kieran.bingham@ideasonboard.com Cc: Jacopo Mondi , niklas.soderlund+renesas@ragnatech.se, linux-media@vger.kernel.org, linux-renesas-soc@vger.kernel.org Subject: Re: [PATCH v2 6/6] media: adv748x: Implement TX link_setup callback Date: Wed, 09 Jan 2019 02:15:04 +0200 Message-ID: <1722143.vWDHCLa8RZ@avalon> Organization: Ideas on Board Oy In-Reply-To: <9f156850-14b6-3ca2-47c1-e03e1bc2c0f8@ideasonboard.com> References: <20190106155413.30666-1-jacopo+renesas@jmondi.org> <20190106155413.30666-7-jacopo+renesas@jmondi.org> <9f156850-14b6-3ca2-47c1-e03e1bc2c0f8@ideasonboard.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Hello, On Monday, 7 January 2019 14:36:28 EET Kieran Bingham wrote: > On 06/01/2019 15:54, Jacopo Mondi wrote: > > When the adv748x driver is informed about a link being created from HDMI > > or AFE to a CSI-2 TX output, the 'link_setup()' callback is invoked. Make > > sure to implement proper routing management at link setup time, to route > > the selected video stream to the desired TX output. > > Overall this looks like the right approach - but I feel like the > handling of the io10 register might need some consideration, because > it's value depends on the condition of both CSI2 transmitters, not just > the currently parsed link. > > I had a go at some pseudo - uncompiled/untested code inline as a suggestion. > > If you think it's better - feel free to rework it in ... or not as you > see fit. > > > Signed-off-by: Jacopo Mondi > > --- > > > > drivers/media/i2c/adv748x/adv748x-core.c | 57 +++++++++++++++++++++++- > > drivers/media/i2c/adv748x/adv748x.h | 2 + > > 2 files changed, 58 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/media/i2c/adv748x/adv748x-core.c > > b/drivers/media/i2c/adv748x/adv748x-core.c index > > 200e00f93546..a586bf393558 100644 > > --- a/drivers/media/i2c/adv748x/adv748x-core.c > > +++ b/drivers/media/i2c/adv748x/adv748x-core.c > > @@ -335,6 +335,60 @@ int adv748x_tx_power(struct adv748x_csi2 *tx, bool > > on) > > /* ---------------------------------------------------------------------- > > * Media Operations > > */ > > +static int adv748x_link_setup(struct media_entity *entity, > > + const struct media_pad *local, > > + const struct media_pad *remote, u32 flags) > > +{ > > + struct v4l2_subdev *rsd = media_entity_to_v4l2_subdev(remote->entity); > > + struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity); > > + struct adv748x_state *state = v4l2_get_subdevdata(sd); > > + struct adv748x_csi2 *tx = adv748x_sd_to_csi2(sd); > > + bool enable = flags & MEDIA_LNK_FL_ENABLED; > > + u8 io10; > > + > > + /* Refuse to enable multiple links to the same TX at the same time. */ > > + if (enable && tx->src) > > + return -EINVAL; > > + > > + /* Set or clear the source (HDMI or AFE) and the current TX. */ > > + if (rsd == &state->afe.sd) > > + state->afe.tx = enable ? tx : NULL; > > + else > > + state->hdmi.tx = enable ? tx : NULL; > > + > > + tx->src = enable ? rsd : NULL; > > + > > + if (!enable) > > + return 0; > > Don't we potentially want to take any action on disable to power down > links below ? > > > + > > + /* Change video stream routing, according to the newly enabled link. */ > > + io10 = io_read(state, ADV748X_IO_10); > > + if (rsd == &state->afe.sd) { > > + /* > > + * Set AFE->TXA routing and power off TXB if AFE goes to TXA. > > + * if AFE goes to TXB, we need both TXA and TXB powered on. > > + */ > > + io10 &= ~ADV748X_IO_10_CSI1_EN; > > + io10 &= ~ADV748X_IO_10_CSI4_IN_SEL_AFE; > > + if (is_txa(tx)) > > + io10 |= ADV748X_IO_10_CSI4_IN_SEL_AFE; > > Shouldn't the CSI4 be enabled here too? or are we assuming it's already > (/always) enabled? > io10 |= ADV748X_IO_10_CSI4_EN; > > > + else > > + io10 |= ADV748X_IO_10_CSI4_EN | > > + ADV748X_IO_10_CSI1_EN; > > + } else { > > + /* Clear AFE->TXA routing and power up TXA. */ > > + io10 &= ~ADV748X_IO_10_CSI4_IN_SEL_AFE; > > + io10 |= ADV748X_IO_10_CSI4_EN; > > But if we assume it's already enabled ... do we need this? > Perhaps it might be better to be explicit on this? > > > + } > > + io_write(state, ADV748X_IO_10, io10); > > Would it be any cleaner to use io_clrset() here? > > Hrm ... also it feels like this register really should be set depending > upon the complete state of ... &state->... > > So perhaps it deserves it's own function which should be called after > csi_registered() callback and any link change. > > /me has a quick go at some psuedo codeishness...: > > int adv74x_io_10(struct adv748x_state *state); > u8 bits = 0; > u8 mask = ADV748X_IO_10_CSI1_EN > > | ADV748X_IO_10_CSI4_EN > | ADV748X_IO_10_CSI4_IN_SEL_AFE; > > if (state->afe.tx) { > /* AFE Requires TXA enabled, even when output to TXB */ > bits |= ADV748X_IO_10_CSI4_EN; > > if (is_txa(state->afe.tx)) > bits |= ADV748X_IO_10_CSI4_IN_SEL_AFE > else > bits |= ADV748X_IO_10_CSI1_EN; > } > > if (state->hdmi.tx) { > bits |= ADV748X_IO_10_CSI4_EN; > } > > return io_clrset(state, ADV748X_IO_10, mask, bits); > } > > How does that look ? (is it even correct first?) > > > + > > + return 0; > > +} > > + > > +static const struct media_entity_operations adv748x_tx_media_ops = { > > + .link_setup = adv748x_link_setup, > > + .link_validate = v4l2_subdev_link_validate, > > +}; > > > > static const struct media_entity_operations adv748x_media_ops = { > > .link_validate = v4l2_subdev_link_validate, > > @@ -516,7 +570,8 @@ void adv748x_subdev_init(struct v4l2_subdev *sd, > > struct adv748x_state *state, > > state->client->addr, ident); > > > > sd->entity.function = function; > > - sd->entity.ops = &adv748x_media_ops; > > + sd->entity.ops = is_tx(adv748x_sd_to_csi2(sd)) ? > > + &adv748x_tx_media_ops : &adv748x_media_ops; > > Aha - yes that's a neat solution to ensure that only the TX links > generate link_setup calls :) Another option would be to bail out from adv748x_link_setup() if the entity is not a TX*. > > } [snip] -- Regards, Laurent Pinchart