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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 03F14C433EF for ; Thu, 25 Nov 2021 16:18:07 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E212A6E02E; Thu, 25 Nov 2021 16:18:05 +0000 (UTC) Received: from mail-ed1-x52a.google.com (mail-ed1-x52a.google.com [IPv6:2a00:1450:4864:20::52a]) by gabe.freedesktop.org (Postfix) with ESMTPS id 675326E02E for ; Thu, 25 Nov 2021 16:18:04 +0000 (UTC) Received: by mail-ed1-x52a.google.com with SMTP id t5so27975839edd.0 for ; Thu, 25 Nov 2021 08:18:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amarulasolutions.com; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=RKugvJ9n3GOzSEfIVIDLjT9SObFLEev7/VUbg0QYI60=; b=jA6Xwz7o3Pn6kf+x2K76koDJIp9P++8Dv6IOOgkLw/RaocYYxu6YVqn59oDBSxww8M Fw4ouBfXwYS58c60SeHKAmXYQ9ct9XOKrIGAJcZy+p2U09UrL8DeU2FqOq+9NMPxYiAa 6QiEmYhmArSnXQ3q8ct9h42asOQnzb2DUG3wg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=RKugvJ9n3GOzSEfIVIDLjT9SObFLEev7/VUbg0QYI60=; b=wJbj6GjvSmjkBRKG32znkpXc+e1+aHHfBoWTmA6OvmRITs2ZFMnZTK1sC3YPBjop0T Uly7bnWfXq9bHPbWZIu06rbImix8vKXW4rouqwAdQ15LXOKW6T3bk4fkmA7BmfDRq1xf KesJrfRql/hCO7fWAvcXUE/tcr5EhH3f49w2o9ad5AiEtNstg9uxV/ibLtWz47yW2X/i svpOaphxis7gXeevmMgQI+CxoIM3GBDq6BaNKhRSum2tNTXOhSTL9KACW6oqxUFjq8BP O+i/NBOGsKQMRMXlAUAhzPQ2aJfful56ITOUDm19Mn90mQHxgETvmT75dTaT99HKVNl9 Xzgg== X-Gm-Message-State: AOAM531I1FWSq/Yjx4gpBB/+0kLefc9pYI+/N5bnE98ajPSDMdYn8lo/ i/eEm55Iim0F0vquoBDqqlX8iOeU8uEDQUvSwnWueA== X-Google-Smtp-Source: ABdhPJw8tf9VDwxLIGm78KbWrvmESJLpuEDI0VtEziVrAxqCC0bOMV84LAgFzaKuiQNTggkENJWpqZZD9DDyK3+IxYo= X-Received: by 2002:a05:6402:445:: with SMTP id p5mr41030370edw.110.1637857082791; Thu, 25 Nov 2021 08:18:02 -0800 (PST) MIME-Version: 1.0 References: <20211122065223.88059-1-jagan@amarulasolutions.com> <20211122065223.88059-4-jagan@amarulasolutions.com> <20211122100712.dls4eqsu6o5gcc5k@gilmour> <20211122140457.jm7cwpp2h3fkf2nd@gilmour> <20211122150449.4nqblhdidb5742x3@gilmour> In-Reply-To: <20211122150449.4nqblhdidb5742x3@gilmour> From: Jagan Teki Date: Thu, 25 Nov 2021 21:47:51 +0530 Message-ID: Subject: Re: [PATCH v5 3/7] drm: sun4i: dsi: Convert to bridge driver To: Maxime Ripard Content-Type: text/plain; charset="UTF-8" X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Neil Armstrong , Robert Foss , linux-sunxi@googlegroups.com, dri-devel@lists.freedesktop.org, Chen-Yu Tsai , Laurent Pinchart , Sam Ravnborg , linux-amarula@amarulasolutions.com, linux-arm-kernel@lists.infradead.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Mon, Nov 22, 2021 at 8:34 PM Maxime Ripard wrote: > > On Mon, Nov 22, 2021 at 07:49:26PM +0530, Jagan Teki wrote: > > On Mon, Nov 22, 2021 at 7:35 PM Maxime Ripard wrote: > > > On Mon, Nov 22, 2021 at 07:18:13PM +0530, Jagan Teki wrote: > > > > On Mon, Nov 22, 2021 at 3:37 PM Maxime Ripard wrote: > > > > > > > > > > On Mon, Nov 22, 2021 at 12:22:19PM +0530, Jagan Teki wrote: > > > > > > Some display panels would come up with a non-DSI output, those > > > > > > can have an option to connect the DSI host by means of interface > > > > > > bridge converter. > > > > > > > > > > > > This DSI to non-DSI interface bridge converter would requires > > > > > > DSI Host to handle drm bridge functionalities in order to DSI > > > > > > Host to Interface bridge. > > > > > > > > > > In order to do this you would need to use the DRM bridge API... > > > > > > > > Sorry, which bridge API do you mean? > > > > > > Any variant of of_drm_find_bridge, and drm_bridge_attach. Just like > > > we're doing in sun4i_rgb.c > > > > Yes, we have drm_bridge_attach in bind and bridge_function.attach > > calls in this patch and of_drm_find_bridge in sun6i_mipi_dsi_attach. > > Not sure which API's I've missed. > > None, that's my point, you don't need anything else in order to do what > you wanted to achieve. Correct, the order is some how confused in this patch. I will fix it in next version. > > > > > > > > > > This patch convert the existing to a drm bridge driver with a > > > > > > built-in encoder support for compatibility with existing > > > > > > component drivers. > > > > > > > > > > ... but changing the encoder driver to a bridge is completely > > > > > unnecessary to do so. Why did you need to make that change? > > > > > > > > Idea of this series is to convert the driver to bridge and use the > > > > latest bridge function from the v1 series. > > > > > > Ok, but it's not at all what you mention in your commit log? You don't > > > need any of that in order to support a bridge downstream. > > > > I've mentioned "Converting to bridge driver" and thought it has > > meaning of converting encoder related function to bridge functions as > > well. Not think about specific description to describe on commit > > message. Will update this. > > But you provided no reason to do so. The only one you did mention was > that you wanted to support downstream bridges, but you don't need to > convert the DSI driver to a bridge in order to do that. Okay. Look like I've combined both downstream bridge support and converting bridge together. This what it totally confused, I will fix it. > > > > > > > Signed-off-by: Jagan Teki > > > > > > > > > > > > --- > > > > > > Changes for v5: > > > > > > - add atomic APIs > > > > > > - find host and device variant DSI devices. > > > > > > Changes for v4, v3: > > > > > > - none > > > > > > > > > > > > drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 112 ++++++++++++++++++++----- > > > > > > drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h | 7 ++ > > > > > > 2 files changed, 96 insertions(+), 23 deletions(-) > > > > > > > > > > > > diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c > > > > > > index 43d9c9e5198d..a6a272b55f77 100644 > > > > > > --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c > > > > > > +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c > > > > > > @@ -21,6 +21,7 @@ > > > > > > > > > > > > #include > > > > > > #include > > > > > > +#include > > > > > > #include > > > > > > #include > > > > > > #include > > > > > > @@ -713,10 +714,11 @@ static int sun6i_dsi_start(struct sun6i_dsi *dsi, > > > > > > return 0; > > > > > > } > > > > > > > > > > > > -static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder) > > > > > > +static void sun6i_dsi_bridge_atomic_enable(struct drm_bridge *bridge, > > > > > > + struct drm_bridge_state *old_bridge_state) > > > > > > { > > > > > > - struct drm_display_mode *mode = &encoder->crtc->state->adjusted_mode; > > > > > > - struct sun6i_dsi *dsi = encoder_to_sun6i_dsi(encoder); > > > > > > + struct sun6i_dsi *dsi = bridge_to_sun6i_dsi(bridge); > > > > > > + struct drm_display_mode *mode = &bridge->encoder->crtc->state->adjusted_mode; > > > > > > struct mipi_dsi_device *device = dsi->device; > > > > > > union phy_configure_opts opts = { }; > > > > > > struct phy_configure_opts_mipi_dphy *cfg = &opts.mipi_dphy; > > > > > > @@ -772,6 +774,9 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder) > > > > > > if (dsi->panel) > > > > > > drm_panel_prepare(dsi->panel); > > > > > > > > > > > > + if (dsi->next_bridge) > > > > > > + dsi->next_bridge->funcs->atomic_pre_enable(dsi->next_bridge, old_bridge_state); > > > > > > + > > > > > > > > > > Please use the proper helpers. > > > > > > > > If we use bridge_functions we need to take atomic functions as > > > > precedence as the next bridge functions might convert atomic calls. > > > > > > We've had this discussion over and over again, but this is something > > > that needs to be documented and / or in your commit log. > > > > > > You must not deviate from the standard (and expected) behavior without > > > any kind of justification. > > > > Not exactly sure about what you mean, sorry. All these atomic bridge > > functions are already documented if I'm not wrong and Laurent have > > patches to switch the normal functions to atomic. Not sure what else > > need to document here and need justification for it if the driver is > > converting to bridge. > > There's two separate bridge in that discussion: the DSI controller > itself that you convert to a bridge, and the downstream DSI -> whatever > bridge. > > The atomic functions in the "DSI controller bridge" are fine. But that > comment was about calling the downstream bridge ops directly from the > driver, which is something that no other driver is doing, deviates from > the expectations, and you didn't provide any explanation for that. Clear for me now. Agreed what you are saying. > > > > > > > > > > > > > > > /* > > > > > > * FIXME: This should be moved after the switch to HS mode. > > > > > > * > > > > > > @@ -787,6 +792,9 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder) > > > > > > if (dsi->panel) > > > > > > drm_panel_enable(dsi->panel); > > > > > > > > > > > > + if (dsi->next_bridge) > > > > > > + dsi->next_bridge->funcs->atomic_enable(dsi->next_bridge, old_bridge_state); > > > > > > + > > > > > > > > > > Ditto > > > > > > > > > > > sun6i_dsi_start(dsi, DSI_START_HSC); > > > > > > > > > > > > udelay(1000); > > > > > > @@ -794,15 +802,19 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder) > > > > > > sun6i_dsi_start(dsi, DSI_START_HSD); > > > > > > } > > > > > > > > > > > > -static void sun6i_dsi_encoder_disable(struct drm_encoder *encoder) > > > > > > +static void sun6i_dsi_bridge_atomic_disable(struct drm_bridge *bridge, > > > > > > + struct drm_bridge_state *old_bridge_state) > > > > > > { > > > > > > - struct sun6i_dsi *dsi = encoder_to_sun6i_dsi(encoder); > > > > > > + struct sun6i_dsi *dsi = bridge_to_sun6i_dsi(bridge); > > > > > > > > > > > > DRM_DEBUG_DRIVER("Disabling DSI output\n"); > > > > > > > > > > > > if (dsi->panel) { > > > > > > drm_panel_disable(dsi->panel); > > > > > > drm_panel_unprepare(dsi->panel); > > > > > > + } else if (dsi->next_bridge) { > > > > > > + dsi->next_bridge->funcs->atomic_disable(dsi->next_bridge, old_bridge_state); > > > > > > + dsi->next_bridge->funcs->atomic_post_disable(dsi->next_bridge, old_bridge_state); > > > > > > > > > > Ditto > > > > > > > > > > > } > > > > > > > > > > > > phy_power_off(dsi->dphy); > > > > > > @@ -842,9 +854,25 @@ static const struct drm_connector_funcs sun6i_dsi_connector_funcs = { > > > > > > .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, > > > > > > }; > > > > > > > > > > > > -static const struct drm_encoder_helper_funcs sun6i_dsi_enc_helper_funcs = { > > > > > > - .disable = sun6i_dsi_encoder_disable, > > > > > > - .enable = sun6i_dsi_encoder_enable, > > > > > > +static int sun6i_dsi_bridge_attach(struct drm_bridge *bridge, > > > > > > + enum drm_bridge_attach_flags flags) > > > > > > +{ > > > > > > + struct sun6i_dsi *dsi = bridge_to_sun6i_dsi(bridge); > > > > > > + > > > > > > + if (dsi->next_bridge) > > > > > > + return drm_bridge_attach(bridge->encoder, dsi->next_bridge, > > > > > > + NULL, 0); > > > > > > + > > > > > > + return 0; > > > > > > +} > > > > > > + > > > > > > +static const struct drm_bridge_funcs sun6i_dsi_bridge_funcs = { > > > > > > + .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state, > > > > > > + .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state, > > > > > > + .atomic_reset = drm_atomic_helper_bridge_reset, > > > > > > + .atomic_enable = sun6i_dsi_bridge_atomic_enable, > > > > > > + .atomic_disable = sun6i_dsi_bridge_atomic_disable, > > > > > > + .attach = sun6i_dsi_bridge_attach, > > > > > > }; > > > > > > > > > > > > static u32 sun6i_dsi_dcs_build_pkt_hdr(struct sun6i_dsi *dsi, > > > > > > @@ -966,8 +994,6 @@ static int sun6i_dsi_bind(struct device *dev, struct device *master, > > > > > > struct sun6i_dsi *dsi = dev_get_drvdata(dev); > > > > > > int ret; > > > > > > > > > > > > - drm_encoder_helper_add(&dsi->encoder, > > > > > > - &sun6i_dsi_enc_helper_funcs); > > > > > > ret = drm_simple_encoder_init(drm, &dsi->encoder, > > > > > > DRM_MODE_ENCODER_DSI); > > > > > > if (ret) { > > > > > > @@ -976,18 +1002,26 @@ static int sun6i_dsi_bind(struct device *dev, struct device *master, > > > > > > } > > > > > > dsi->encoder.possible_crtcs = BIT(0); > > > > > > > > > > > > - drm_connector_helper_add(&dsi->connector, > > > > > > - &sun6i_dsi_connector_helper_funcs); > > > > > > - ret = drm_connector_init(drm, &dsi->connector, > > > > > > - &sun6i_dsi_connector_funcs, > > > > > > - DRM_MODE_CONNECTOR_DSI); > > > > > > + ret = drm_bridge_attach(&dsi->encoder, &dsi->bridge, NULL, 0); > > > > > > if (ret) { > > > > > > - dev_err(dsi->dev, > > > > > > - "Couldn't initialise the DSI connector\n"); > > > > > > + dev_err(dsi->dev, "Couldn't attach drm bridge\n"); > > > > > > goto err_cleanup_connector; > > > > > > } > > > > > > > > > > > > - drm_connector_attach_encoder(&dsi->connector, &dsi->encoder); > > > > > > + if (dsi->panel) { > > > > > > + drm_connector_helper_add(&dsi->connector, > > > > > > + &sun6i_dsi_connector_helper_funcs); > > > > > > + ret = drm_connector_init(drm, &dsi->connector, > > > > > > + &sun6i_dsi_connector_funcs, > > > > > > + DRM_MODE_CONNECTOR_DSI); > > > > > > + if (ret) { > > > > > > + dev_err(dsi->dev, > > > > > > + "Couldn't initialise the DSI connector\n"); > > > > > > + goto err_cleanup_connector; > > > > > > + } > > > > > > + > > > > > > + drm_connector_attach_encoder(&dsi->connector, &dsi->encoder); > > > > > > + } > > > > > > > > > > > > return 0; > > > > > > > > > > > > @@ -1013,16 +1047,46 @@ static int sun6i_dsi_attach(struct mipi_dsi_host *host, > > > > > > struct mipi_dsi_device *device) > > > > > > { > > > > > > struct sun6i_dsi *dsi = host_to_sun6i_dsi(host); > > > > > > - struct drm_panel *panel = of_drm_find_panel(device->dev.of_node); > > > > > > + struct device_node *remote = device->dev.of_node; > > > > > > int ret; > > > > > > > > > > > > - if (IS_ERR(panel)) > > > > > > - return PTR_ERR(panel); > > > > > > + if (!of_device_is_available(remote)) { > > > > > > + /** > > > > > > + * I2C interfaced DSI bridges will register DSI host on the > > > > > > + * bridge drivers instead of conventional device. > > > > > > + * > > > > > > + * Those are probed via host of_node instead of device of_node. > > > > > > + */ > > > > > > > > > > I have no idea what you mean here. Can you expand on what issue you've > > > > > tried to solve here? > > > > > > > > I2C interface DSI bridges will register DSI host on the bridge > > > > drivers. > > > > > > DSI bridges don't register a DSI host. > > > > Please check what I mean here, > > https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/gpu/drm/bridge/ti-sn65dsi83.c#n623 > > > > I've tested it anyway, if you have any relevant one please check as well. > > That driver doesn't register a DSI Host though? It registers a DSI > device Correct. Thanks, Jagan. 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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A8875C433EF for ; Thu, 25 Nov 2021 16:21:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:Subject:Message-ID:Date:From: In-Reply-To:References:MIME-Version:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=2uHxPnaO+7+s3R1k649W4FYt4RzTxBClpOEvt4fHDmk=; b=dseERNXwpsXDmi ESecmli+NccYepeDlX0rp3uxtC50lHZXxf/gJkOAJblGLJT4sr5MhkqjgHB9gXVhQRqEeZopPl8cF 7M+NwsytbH5OcJ3rZyujJCWg2x/9EPpS5DcjJ6JaWkzFHXiAzYP3FnGLxxrsXKolvnTnx9MnDg5Rf lXXko1sf26ktGVTCJ4cZ0DFjvMkR9IsKBpTbjY6VwPRyWqkXQCNdZUUFOeyTWa0lS7DsLxsmN0p5d U3t3ThrnMcLGrUDtHiKLj8ah6jpVBUcc/9I8DdhHol+kfi+6hg/1P1HNXOURfWNI14zlTkRD6jiep yTGra1yxK5wLcGmEPGgQ==; 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h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=RKugvJ9n3GOzSEfIVIDLjT9SObFLEev7/VUbg0QYI60=; b=SriESC3qKl+ixhdT5Lp9AvYy+99kGs3PcKHI/XGHRUzmqyq6hFWm9AIc7kMLrRWiXg I4HClV2F93xFSFJ9N4tVXcMvJokpLpzAGAlWVjNPWP5FkQoM763dcg9ox0awBdNVqgHt odvEXTQu8c2ZG7dF7hI1LeC0KFPLWcRPbqfrKLgaIEx+giNzpJ8/T6dtZfGBtqintKbF GXTT4beqGAkcDgfP/2hAvNUl4qzOeWPRkfJkw1REnN6XroTgb5z21sXlgDTWWPAi9ruD wYRLrpYf8wg4Zslu6/J9d1VBIuUU9/+QohZa/tB5QhCWwYlt1axe9UOWcR1BEF8SgaPZ rQzQ== X-Gm-Message-State: AOAM533UqShAptN3+SFlNS3p9n0MAVdCyZZjhrY1RV3ZJuEI3ugJhCzK WH8nKOCbgCmxxUVPFTIIQnboSvxQgCNaf9J9Q+dcSg== X-Google-Smtp-Source: ABdhPJw8tf9VDwxLIGm78KbWrvmESJLpuEDI0VtEziVrAxqCC0bOMV84LAgFzaKuiQNTggkENJWpqZZD9DDyK3+IxYo= X-Received: by 2002:a05:6402:445:: with SMTP id p5mr41030370edw.110.1637857082791; Thu, 25 Nov 2021 08:18:02 -0800 (PST) MIME-Version: 1.0 References: <20211122065223.88059-1-jagan@amarulasolutions.com> <20211122065223.88059-4-jagan@amarulasolutions.com> <20211122100712.dls4eqsu6o5gcc5k@gilmour> <20211122140457.jm7cwpp2h3fkf2nd@gilmour> <20211122150449.4nqblhdidb5742x3@gilmour> In-Reply-To: <20211122150449.4nqblhdidb5742x3@gilmour> From: Jagan Teki Date: Thu, 25 Nov 2021 21:47:51 +0530 Message-ID: Subject: Re: [PATCH v5 3/7] drm: sun4i: dsi: Convert to bridge driver To: Maxime Ripard Cc: Chen-Yu Tsai , Laurent Pinchart , Neil Armstrong , Robert Foss , Sam Ravnborg , dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@googlegroups.com, linux-amarula@amarulasolutions.com X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211125_081804_650504_D8F84792 X-CRM114-Status: GOOD ( 58.02 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Nov 22, 2021 at 8:34 PM Maxime Ripard wrote: > > On Mon, Nov 22, 2021 at 07:49:26PM +0530, Jagan Teki wrote: > > On Mon, Nov 22, 2021 at 7:35 PM Maxime Ripard wrote: > > > On Mon, Nov 22, 2021 at 07:18:13PM +0530, Jagan Teki wrote: > > > > On Mon, Nov 22, 2021 at 3:37 PM Maxime Ripard wrote: > > > > > > > > > > On Mon, Nov 22, 2021 at 12:22:19PM +0530, Jagan Teki wrote: > > > > > > Some display panels would come up with a non-DSI output, those > > > > > > can have an option to connect the DSI host by means of interface > > > > > > bridge converter. > > > > > > > > > > > > This DSI to non-DSI interface bridge converter would requires > > > > > > DSI Host to handle drm bridge functionalities in order to DSI > > > > > > Host to Interface bridge. > > > > > > > > > > In order to do this you would need to use the DRM bridge API... > > > > > > > > Sorry, which bridge API do you mean? > > > > > > Any variant of of_drm_find_bridge, and drm_bridge_attach. Just like > > > we're doing in sun4i_rgb.c > > > > Yes, we have drm_bridge_attach in bind and bridge_function.attach > > calls in this patch and of_drm_find_bridge in sun6i_mipi_dsi_attach. > > Not sure which API's I've missed. > > None, that's my point, you don't need anything else in order to do what > you wanted to achieve. Correct, the order is some how confused in this patch. I will fix it in next version. > > > > > > > > > > This patch convert the existing to a drm bridge driver with a > > > > > > built-in encoder support for compatibility with existing > > > > > > component drivers. > > > > > > > > > > ... but changing the encoder driver to a bridge is completely > > > > > unnecessary to do so. Why did you need to make that change? > > > > > > > > Idea of this series is to convert the driver to bridge and use the > > > > latest bridge function from the v1 series. > > > > > > Ok, but it's not at all what you mention in your commit log? You don't > > > need any of that in order to support a bridge downstream. > > > > I've mentioned "Converting to bridge driver" and thought it has > > meaning of converting encoder related function to bridge functions as > > well. Not think about specific description to describe on commit > > message. Will update this. > > But you provided no reason to do so. The only one you did mention was > that you wanted to support downstream bridges, but you don't need to > convert the DSI driver to a bridge in order to do that. Okay. Look like I've combined both downstream bridge support and converting bridge together. This what it totally confused, I will fix it. > > > > > > > Signed-off-by: Jagan Teki > > > > > > > > > > > > --- > > > > > > Changes for v5: > > > > > > - add atomic APIs > > > > > > - find host and device variant DSI devices. > > > > > > Changes for v4, v3: > > > > > > - none > > > > > > > > > > > > drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 112 ++++++++++++++++++++----- > > > > > > drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h | 7 ++ > > > > > > 2 files changed, 96 insertions(+), 23 deletions(-) > > > > > > > > > > > > diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c > > > > > > index 43d9c9e5198d..a6a272b55f77 100644 > > > > > > --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c > > > > > > +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c > > > > > > @@ -21,6 +21,7 @@ > > > > > > > > > > > > #include > > > > > > #include > > > > > > +#include > > > > > > #include > > > > > > #include > > > > > > #include > > > > > > @@ -713,10 +714,11 @@ static int sun6i_dsi_start(struct sun6i_dsi *dsi, > > > > > > return 0; > > > > > > } > > > > > > > > > > > > -static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder) > > > > > > +static void sun6i_dsi_bridge_atomic_enable(struct drm_bridge *bridge, > > > > > > + struct drm_bridge_state *old_bridge_state) > > > > > > { > > > > > > - struct drm_display_mode *mode = &encoder->crtc->state->adjusted_mode; > > > > > > - struct sun6i_dsi *dsi = encoder_to_sun6i_dsi(encoder); > > > > > > + struct sun6i_dsi *dsi = bridge_to_sun6i_dsi(bridge); > > > > > > + struct drm_display_mode *mode = &bridge->encoder->crtc->state->adjusted_mode; > > > > > > struct mipi_dsi_device *device = dsi->device; > > > > > > union phy_configure_opts opts = { }; > > > > > > struct phy_configure_opts_mipi_dphy *cfg = &opts.mipi_dphy; > > > > > > @@ -772,6 +774,9 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder) > > > > > > if (dsi->panel) > > > > > > drm_panel_prepare(dsi->panel); > > > > > > > > > > > > + if (dsi->next_bridge) > > > > > > + dsi->next_bridge->funcs->atomic_pre_enable(dsi->next_bridge, old_bridge_state); > > > > > > + > > > > > > > > > > Please use the proper helpers. > > > > > > > > If we use bridge_functions we need to take atomic functions as > > > > precedence as the next bridge functions might convert atomic calls. > > > > > > We've had this discussion over and over again, but this is something > > > that needs to be documented and / or in your commit log. > > > > > > You must not deviate from the standard (and expected) behavior without > > > any kind of justification. > > > > Not exactly sure about what you mean, sorry. All these atomic bridge > > functions are already documented if I'm not wrong and Laurent have > > patches to switch the normal functions to atomic. Not sure what else > > need to document here and need justification for it if the driver is > > converting to bridge. > > There's two separate bridge in that discussion: the DSI controller > itself that you convert to a bridge, and the downstream DSI -> whatever > bridge. > > The atomic functions in the "DSI controller bridge" are fine. But that > comment was about calling the downstream bridge ops directly from the > driver, which is something that no other driver is doing, deviates from > the expectations, and you didn't provide any explanation for that. Clear for me now. Agreed what you are saying. > > > > > > > > > > > > > > > /* > > > > > > * FIXME: This should be moved after the switch to HS mode. > > > > > > * > > > > > > @@ -787,6 +792,9 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder) > > > > > > if (dsi->panel) > > > > > > drm_panel_enable(dsi->panel); > > > > > > > > > > > > + if (dsi->next_bridge) > > > > > > + dsi->next_bridge->funcs->atomic_enable(dsi->next_bridge, old_bridge_state); > > > > > > + > > > > > > > > > > Ditto > > > > > > > > > > > sun6i_dsi_start(dsi, DSI_START_HSC); > > > > > > > > > > > > udelay(1000); > > > > > > @@ -794,15 +802,19 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder) > > > > > > sun6i_dsi_start(dsi, DSI_START_HSD); > > > > > > } > > > > > > > > > > > > -static void sun6i_dsi_encoder_disable(struct drm_encoder *encoder) > > > > > > +static void sun6i_dsi_bridge_atomic_disable(struct drm_bridge *bridge, > > > > > > + struct drm_bridge_state *old_bridge_state) > > > > > > { > > > > > > - struct sun6i_dsi *dsi = encoder_to_sun6i_dsi(encoder); > > > > > > + struct sun6i_dsi *dsi = bridge_to_sun6i_dsi(bridge); > > > > > > > > > > > > DRM_DEBUG_DRIVER("Disabling DSI output\n"); > > > > > > > > > > > > if (dsi->panel) { > > > > > > drm_panel_disable(dsi->panel); > > > > > > drm_panel_unprepare(dsi->panel); > > > > > > + } else if (dsi->next_bridge) { > > > > > > + dsi->next_bridge->funcs->atomic_disable(dsi->next_bridge, old_bridge_state); > > > > > > + dsi->next_bridge->funcs->atomic_post_disable(dsi->next_bridge, old_bridge_state); > > > > > > > > > > Ditto > > > > > > > > > > > } > > > > > > > > > > > > phy_power_off(dsi->dphy); > > > > > > @@ -842,9 +854,25 @@ static const struct drm_connector_funcs sun6i_dsi_connector_funcs = { > > > > > > .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, > > > > > > }; > > > > > > > > > > > > -static const struct drm_encoder_helper_funcs sun6i_dsi_enc_helper_funcs = { > > > > > > - .disable = sun6i_dsi_encoder_disable, > > > > > > - .enable = sun6i_dsi_encoder_enable, > > > > > > +static int sun6i_dsi_bridge_attach(struct drm_bridge *bridge, > > > > > > + enum drm_bridge_attach_flags flags) > > > > > > +{ > > > > > > + struct sun6i_dsi *dsi = bridge_to_sun6i_dsi(bridge); > > > > > > + > > > > > > + if (dsi->next_bridge) > > > > > > + return drm_bridge_attach(bridge->encoder, dsi->next_bridge, > > > > > > + NULL, 0); > > > > > > + > > > > > > + return 0; > > > > > > +} > > > > > > + > > > > > > +static const struct drm_bridge_funcs sun6i_dsi_bridge_funcs = { > > > > > > + .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state, > > > > > > + .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state, > > > > > > + .atomic_reset = drm_atomic_helper_bridge_reset, > > > > > > + .atomic_enable = sun6i_dsi_bridge_atomic_enable, > > > > > > + .atomic_disable = sun6i_dsi_bridge_atomic_disable, > > > > > > + .attach = sun6i_dsi_bridge_attach, > > > > > > }; > > > > > > > > > > > > static u32 sun6i_dsi_dcs_build_pkt_hdr(struct sun6i_dsi *dsi, > > > > > > @@ -966,8 +994,6 @@ static int sun6i_dsi_bind(struct device *dev, struct device *master, > > > > > > struct sun6i_dsi *dsi = dev_get_drvdata(dev); > > > > > > int ret; > > > > > > > > > > > > - drm_encoder_helper_add(&dsi->encoder, > > > > > > - &sun6i_dsi_enc_helper_funcs); > > > > > > ret = drm_simple_encoder_init(drm, &dsi->encoder, > > > > > > DRM_MODE_ENCODER_DSI); > > > > > > if (ret) { > > > > > > @@ -976,18 +1002,26 @@ static int sun6i_dsi_bind(struct device *dev, struct device *master, > > > > > > } > > > > > > dsi->encoder.possible_crtcs = BIT(0); > > > > > > > > > > > > - drm_connector_helper_add(&dsi->connector, > > > > > > - &sun6i_dsi_connector_helper_funcs); > > > > > > - ret = drm_connector_init(drm, &dsi->connector, > > > > > > - &sun6i_dsi_connector_funcs, > > > > > > - DRM_MODE_CONNECTOR_DSI); > > > > > > + ret = drm_bridge_attach(&dsi->encoder, &dsi->bridge, NULL, 0); > > > > > > if (ret) { > > > > > > - dev_err(dsi->dev, > > > > > > - "Couldn't initialise the DSI connector\n"); > > > > > > + dev_err(dsi->dev, "Couldn't attach drm bridge\n"); > > > > > > goto err_cleanup_connector; > > > > > > } > > > > > > > > > > > > - drm_connector_attach_encoder(&dsi->connector, &dsi->encoder); > > > > > > + if (dsi->panel) { > > > > > > + drm_connector_helper_add(&dsi->connector, > > > > > > + &sun6i_dsi_connector_helper_funcs); > > > > > > + ret = drm_connector_init(drm, &dsi->connector, > > > > > > + &sun6i_dsi_connector_funcs, > > > > > > + DRM_MODE_CONNECTOR_DSI); > > > > > > + if (ret) { > > > > > > + dev_err(dsi->dev, > > > > > > + "Couldn't initialise the DSI connector\n"); > > > > > > + goto err_cleanup_connector; > > > > > > + } > > > > > > + > > > > > > + drm_connector_attach_encoder(&dsi->connector, &dsi->encoder); > > > > > > + } > > > > > > > > > > > > return 0; > > > > > > > > > > > > @@ -1013,16 +1047,46 @@ static int sun6i_dsi_attach(struct mipi_dsi_host *host, > > > > > > struct mipi_dsi_device *device) > > > > > > { > > > > > > struct sun6i_dsi *dsi = host_to_sun6i_dsi(host); > > > > > > - struct drm_panel *panel = of_drm_find_panel(device->dev.of_node); > > > > > > + struct device_node *remote = device->dev.of_node; > > > > > > int ret; > > > > > > > > > > > > - if (IS_ERR(panel)) > > > > > > - return PTR_ERR(panel); > > > > > > + if (!of_device_is_available(remote)) { > > > > > > + /** > > > > > > + * I2C interfaced DSI bridges will register DSI host on the > > > > > > + * bridge drivers instead of conventional device. > > > > > > + * > > > > > > + * Those are probed via host of_node instead of device of_node. > > > > > > + */ > > > > > > > > > > I have no idea what you mean here. Can you expand on what issue you've > > > > > tried to solve here? > > > > > > > > I2C interface DSI bridges will register DSI host on the bridge > > > > drivers. > > > > > > DSI bridges don't register a DSI host. > > > > Please check what I mean here, > > https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/gpu/drm/bridge/ti-sn65dsi83.c#n623 > > > > I've tested it anyway, if you have any relevant one please check as well. > > That driver doesn't register a DSI Host though? It registers a DSI > device Correct. Thanks, Jagan. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel