From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752339AbeCLI0r (ORCPT ); Mon, 12 Mar 2018 04:26:47 -0400 Received: from mailout2.w1.samsung.com ([210.118.77.12]:49328 "EHLO mailout2.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752248AbeCLI0k (ORCPT ); Mon, 12 Mar 2018 04:26:40 -0400 DKIM-Filter: OpenDKIM Filter v2.11.0 mailout2.w1.samsung.com 20180312082637euoutp0239857dc9d31d318cc3992fcc58d5587a~bHtSNraud0691406914euoutp02J X-AuditID: cbfec7f2-1c1ff70000011644-77-5aa639bbee70 Subject: Re: [PATCH v2 2/3] drm: bridge: Add LVDS decoder driver To: Jacopo Mondi , architt@codeaurora.org, Laurent.pinchart@ideasonboard.com, airlied@linux.ie, horms@verge.net.au, magnus.damm@gmail.com, geert@linux-m68k.org, niklas.soderlund@ragnatech.se, sergei.shtylyov@cogentembedded.com, robh+dt@kernel.org, mark.rutland@arm.com Cc: dri-devel@lists.freedesktop.org, linux-renesas-soc@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org From: Andrzej Hajda Message-ID: Date: Mon, 12 Mar 2018 09:26:33 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <1520603500-15218-3-git-send-email-jacopo+renesas@jmondi.org> Content-Transfer-Encoding: 8bit Content-Language: en-US X-Brightmail-Tracker: H4sIAAAAAAAAA01Sa0iTYRTm/W77tFavM9thZdHE0CxNEP2iNAPDr0io/BP7US39MMlLbJla VDK7zFs3qWja3VtqpNYyLX80yzEtTddFJXOUZRbLsKxkqTm/Rf57znPOc87zwGFJmYNWsIkp +wRNijpJybhT91rGOlY8WFWmWllVH8AVtFsITqe309yVx+0092J0mOE+9jYRXLZxFHFmxy0J l3OmRMJZG4sZzjj0leBsVXaGK33dSXDm8ydp7ljTYwn3tLJXEjmXr75cjXjryQKCt52bJPgG Q5+EL9JfpPnJ7nckX1eZw/CmZj3i63/aaL4/z0zwg9ZfDF889pPiv9ct2ixVua+JF5IS9wua oIid7rvv3hwh9pYEZbRmLc9CnUtzkRsLOARyeyx0LnJnZbgCwanrD1zFDwR/XpcTYvEdwVHb E+qfRO9472qUT0leTrgkdgT5753L3FhPHAmNVSMSZ2MevkWAZfg35SxIrEPQZckmnVMM9ofx Oz2ME0txBLTozNOYwr5gKjgxjb3wNrh27gMSZzzAcnFgahHLuuGN0DGe7qRJvBiyjUWkiOXQ O3Bl2h7gUhZqy9okou8osJ5vYkTsCZ/Nd138QmgrzHdlOwg9n3SUKNYj6HeccAlWQ7O5k3Ye JqdM324MEulwcNSYJE4a8BzotnuIHubA2XsXSJGWgv64TJxeAv3PjKSI5VD6fJQ5jXwMM4IZ ZqQxzEhj+H/3KqIqkVxI0yYnCNrgFCE9UKtO1qalJATGpSbXoamXbJswj9xHo127TAizSDlb GllTqpLR6v3azGQTApZUzpO+8S9TyaTx6swDgiZ1hyYtSdCa0AKWUsql2/0Oq2Q4Qb1P2CMI ewXNvy7BuimyEFW+9nKB93BctPTGr4kJ28g6fVJFtLpvxZCCMM3fFPrtXe3vL+tDtlaXzwoe HlNUT4Ycis2PCbAXxnyu9xiM2hi2zW/LqwyF70OvS7E+QbpluOpRelxO5trWaGsE7jOseauo bHhbW2gM8y4aO3I6IjSvfkN7ONe9qtgrr6HIL6dLrqS0u9XBy0iNVv0XfGDq8o4DAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFupjleLIzCtJLcpLzFFi42I5/e/4Pd1dlsuiDNY1mVn0njvJZNHU8ZbV Yv6Rc6wWV76+Z7N4dmsvk0Xz1q+MFsd/r2W36Jy4hN3i8q45bBZbX75jsniw+i2bxdLrF5ks jk/rY7Vo3XuE3eLMqlvsDvwea+atYfS43NfL5PFg6n8mj52z7rJ7zO6Yyerx/8YjZo9NqzrZ PA4d7mD02P7tAavH/e7jTB7PL39n85jz8xuLx+dNcgG8UXo2RfmlJakKGfnFJbZK0YYWRnqG lhZ6RiaWeobG5rFWRqZK+nY2Kak5mWWpRfp2CXoZW1Z+YipYol9xqkGngfGiWhcjJ4eEgIlE x+/HTF2MXBxCAksZJe6fes0GkRCX2D3/LTOELSzx51oXG0TRa0aJb08WsIMkhAUcJHat/sQO khARWMsk8eTIAmYQh1mgiVFiwuxPUHPvAjmPfrCAtLAJaEr83XwTbAevgJ3EsabjYDaLgKrE od52MFtUIEKic+V8FogaQYmTM58A2RwcnAJeEuf/loOEmQXUJf7Mu8QMYctLNG+dDWWLS9x6 Mp9pAqPQLCTds5C0zELSMgtJywJGllWMIqmlxbnpucWGesWJucWleel6yfm5mxiBaWHbsZ+b dzBe2hh8iFGAg1GJh3fGpqVRQqyJZcWVuYcYJTiYlUR472guixLiTUmsrEotyo8vKs1JLT7E aAr020RmKdHkfGDKyiuJNzQ1NLewNDQ3Njc2s1AS5z1vUBklJJCeWJKanZpakFoE08fEwSnV wBj+Rkvsw5nsIw0Tv7uznTqpqnfu0NzLW7etmNw6Y8U6pvnGSvMKoqvfs3HLtGa2BhvslP3D pj75cz9bym/D4CCjfZkf+kMWTwqvELq3YK3eVZdOfomVc8OfRTY+bjO2LzZh/vj307J/KjYh rsGub4oZ42+8Df+dclfYQu6YyXp3l7l+YfdUqpVYijMSDbWYi4oTAf/DZMshAwAA X-CMS-MailID: 20180312082635eucas1p2afec8684135fc2e4b765342e3b3bc8ba X-Msg-Generator: CA Content-Type: text/plain; charset="utf-8" X-MTR: 20180312082635eucas1p2afec8684135fc2e4b765342e3b3bc8ba X-EPHeader: CA CMS-TYPE: 201P X-CMS-RootMailID: 20180309135214epcas5p26c0b31def45b1fb5a41c7adcc9a45f92 X-RootMTR: 20180309135214epcas5p26c0b31def45b1fb5a41c7adcc9a45f92 References: <1520603500-15218-1-git-send-email-jacopo+renesas@jmondi.org> <1520603500-15218-3-git-send-email-jacopo+renesas@jmondi.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09.03.2018 14:51, Jacopo Mondi wrote: > Add transparent LVDS decoder driver. > > A transparent LVDS decoder is a DRM bridge device that does not require > any configuration and converts LVDS input to digital CMOS/TTL parallel > data output. Neither code, neither bindings are LVDS specific, this is driver for any bridge w/o configuration. I  am not sure how many bridges does not need configuration, usually they need to be powered at least. I guess in many cases power line is always on, but this is board specific not device specific. Looking at previous version of the patchset it looks little bit as a hack, and certainly it will be a hack in case of R-Car Gen3 V3M Eagle, which I guess you want to use it. > Signed-off-by: Jacopo Mondi > --- > drivers/gpu/drm/bridge/Kconfig | 8 +++ > drivers/gpu/drm/bridge/Makefile | 1 + > drivers/gpu/drm/bridge/lvds-decoder.c | 129 ++++++++++++++++++++++++++++++++++ > 3 files changed, 138 insertions(+) > create mode 100644 drivers/gpu/drm/bridge/lvds-decoder.c > > diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig > index 3b99d5a..e52a5af 100644 > --- a/drivers/gpu/drm/bridge/Kconfig > +++ b/drivers/gpu/drm/bridge/Kconfig > @@ -32,6 +32,14 @@ config DRM_DUMB_VGA_DAC > help > Support for RGB to VGA DAC based bridges > > +config DRM_LVDS_DECODER > + tristate "Transparent LVDS to parallel decoder support" > + depends on OF > + select DRM_PANEL_BRIDGE > + help > + Support for transparent LVDS to parallel decoders that don't require > + any configuration. > + > config DRM_LVDS_ENCODER > tristate "Transparent parallel to LVDS encoder support" > depends on OF > diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile > index 373eb28..edc2332 100644 > --- a/drivers/gpu/drm/bridge/Makefile > +++ b/drivers/gpu/drm/bridge/Makefile > @@ -1,6 +1,7 @@ > # SPDX-License-Identifier: GPL-2.0 > obj-$(CONFIG_DRM_ANALOGIX_ANX78XX) += analogix-anx78xx.o > obj-$(CONFIG_DRM_DUMB_VGA_DAC) += dumb-vga-dac.o > +obj-$(CONFIG_DRM_LVDS_DECODER) += lvds-decoder.o > obj-$(CONFIG_DRM_LVDS_ENCODER) += lvds-encoder.o > obj-$(CONFIG_DRM_MEGACHIPS_STDPXXXX_GE_B850V3_FW) += megachips-stdpxxxx-ge-b850v3-fw.o > obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o > diff --git a/drivers/gpu/drm/bridge/lvds-decoder.c b/drivers/gpu/drm/bridge/lvds-decoder.c > new file mode 100644 > index 0000000..319f4d5 > --- /dev/null > +++ b/drivers/gpu/drm/bridge/lvds-decoder.c > @@ -0,0 +1,129 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * LVDS to parallel data DRM bridge driver. > + * > + * Copyright (C) 2018 Jacopo Mondi > + */ > + > +#include > +#include > +#include > + > +#include > + > +struct lvds_decoder { > + struct device *dev; > + > + struct drm_bridge bridge; > + struct drm_bridge *next; > + struct drm_encoder *bridge_encoder; Unused field. Regards Andrzej > +}; > + > +static inline struct lvds_decoder *to_lvds_decoder(struct drm_bridge *bridge) > +{ > + return container_of(bridge, struct lvds_decoder, bridge); > +} > + > +static int lvds_decoder_attach(struct drm_bridge *bridge) > +{ > + struct lvds_decoder *lvds = to_lvds_decoder(bridge); > + > + return drm_bridge_attach(bridge->encoder, lvds->next, bridge); > +} > + > +struct drm_bridge_funcs lvds_dec_bridge_func = { > + .attach = lvds_decoder_attach, > +}; > + > +static int lvds_decoder_parse_dt(struct lvds_decoder *lvds) > +{ > + struct device_node *lvds_output; > + struct device_node *remote; > + int ret = 0; > + > + lvds_output = of_graph_get_endpoint_by_regs(lvds->dev->of_node, 1, -1); > + if (!lvds_output) { > + dev_err(lvds->dev, "Missing endpoint in Port@1\n"); > + return -ENODEV; > + } > + > + remote = of_graph_get_remote_port_parent(lvds_output); > + if (!remote) { > + dev_err(lvds->dev, "Endpoint in Port@1 unconnected\n"); > + ret = -ENODEV; > + goto error_put_lvds_node; > + } > + > + if (!of_device_is_available(remote)) { > + dev_err(lvds->dev, "Port@1 remote endpoint is disabled\n"); > + ret = -ENODEV; > + goto error_put_remote_node; > + } > + > + lvds->next = of_drm_find_bridge(remote); > + if (!lvds->next) > + ret = -EPROBE_DEFER; > + > +error_put_remote_node: > + of_node_put(remote); > +error_put_lvds_node: > + of_node_put(lvds_output); > + > + return ret; > +} > + > +static int lvds_decoder_probe(struct platform_device *pdev) > +{ > + struct lvds_decoder *lvds; > + int ret; > + > + lvds = devm_kzalloc(&pdev->dev, sizeof(*lvds), GFP_KERNEL); > + if (!lvds) > + return -ENOMEM; > + > + lvds->dev = &pdev->dev; > + platform_set_drvdata(pdev, lvds); > + > + ret = lvds_decoder_parse_dt(lvds); > + if (ret) > + return ret; > + > + lvds->bridge.driver_private = lvds; > + lvds->bridge.of_node = pdev->dev.of_node; > + lvds->bridge.funcs = &lvds_dec_bridge_func; > + > + drm_bridge_add(&lvds->bridge); > + > + return 0; > +} > + > +static int lvds_decoder_remove(struct platform_device *pdev) > +{ > + struct lvds_decoder *lvds = platform_get_drvdata(pdev); > + > + drm_bridge_remove(&lvds->bridge); > + > + return 0; > +} > + > +#ifdef CONFIG_OF > +static const struct of_device_id lvds_decoder_match[] = { > + { .compatible = "lvds-decoder", }, > + { }, > +}; > +MODULE_DEVICE_TABLE(of, lvds_decoder_match); > +#endif > + > +static struct platform_driver lvds_decoder_driver = { > + .probe = lvds_decoder_probe, > + .remove = lvds_decoder_remove, > + .driver = { > + .name = "lvds_decoder", > + .of_match_table = lvds_decoder_match, > + }, > +}; > +module_platform_driver(lvds_decoder_driver); > + > +MODULE_AUTHOR("Jacopo Mondi "); > +MODULE_DESCRIPTION("Transparent LVDS to parallel data decoder"); > +MODULE_LICENSE("GPL v2"); > -- > 2.7.4 > > > >