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=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 ABB73C31E49 for ; Sun, 16 Jun 2019 12:48:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 731F220870 for ; Sun, 16 Jun 2019 12:48:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=megous.com header.i=@megous.com header.b="oPWAnWFI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727206AbfFPMsO (ORCPT ); Sun, 16 Jun 2019 08:48:14 -0400 Received: from vps.xff.cz ([195.181.215.36]:38520 "EHLO vps.xff.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725865AbfFPMsN (ORCPT ); Sun, 16 Jun 2019 08:48:13 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=megous.com; s=mail; t=1560689291; bh=qBJ9B0Xckt+HWWzbJLcLsikCH1xzty0YELtzbx90mkg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=oPWAnWFIpuRP6ETv3DDOQhM2QI5kMHea+JQ32AOu9youL4NSvqwmFmwzXYjtOhgdA 9FWoqGNXIs5wK/hiNjCxjUjOv+QJdWBWe6127EOIZR5gMeJOLnvT3x21C0m0lSYmRi irBZ/5vrY7a8yh1CJv8ZAHM8V3ZnQc1CETSSkceI= Date: Sun, 16 Jun 2019 14:48:10 +0200 From: =?utf-8?Q?Ond=C5=99ej?= Jirman To: Jernej =?utf-8?Q?=C5=A0krabec?= Cc: linux-sunxi@googlegroups.com, Maxime Ripard , Chen-Yu Tsai , Rob Herring , David Airlie , Daniel Vetter , Mark Rutland , Giuseppe Cavallaro , Alexandre Torgue , Jose Abreu , "David S. Miller" , Maxime Coquelin , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com Subject: Re: [linux-sunxi] [PATCH v6 5/6] drm: sun4i: Add support for enabling DDC I2C bus to sun8i_dw_hdmi glue Message-ID: <20190616124810.qvlij6zkcl3leu3d@core.my.home> Mail-Followup-To: Jernej =?utf-8?Q?=C5=A0krabec?= , linux-sunxi@googlegroups.com, Maxime Ripard , Chen-Yu Tsai , Rob Herring , David Airlie , Daniel Vetter , Mark Rutland , Giuseppe Cavallaro , Alexandre Torgue , Jose Abreu , "David S. Miller" , Maxime Coquelin , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com References: <20190527162237.18495-1-megous@megous.com> <20190527162237.18495-6-megous@megous.com> <1823986.m04BvQ5ALy@jernej-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1823986.m04BvQ5ALy@jernej-laptop> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jernej, On Sun, Jun 16, 2019 at 01:05:13PM +0200, Jernej Škrabec wrote: > Hi Ondrej! > > Dne ponedeljek, 27. maj 2019 ob 18:22:36 CEST je megous via linux-sunxi > napisal(a): > > From: Ondrej Jirman > > > > Orange Pi 3 board requires enabling a voltage shifting circuit via GPIO > > for the DDC bus to be usable. > > > > Add support for hdmi-connector node's optional ddc-en-gpios property to > > support this use case. > > > > Signed-off-by: Ondrej Jirman > > --- > > drivers/gpu/drm/sun4i/sun8i_dw_hdmi.c | 55 +++++++++++++++++++++++++-- > > drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h | 3 ++ > > 2 files changed, 55 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.c > > b/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.c index 39d8509d96a0..59b81ba02d96 > > 100644 > > --- a/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.c > > +++ b/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.c > > @@ -98,6 +98,30 @@ static u32 sun8i_dw_hdmi_find_possible_crtcs(struct > > drm_device *drm, return crtcs; > > } > > > > +static int sun8i_dw_hdmi_find_connector_pdev(struct device *dev, > > + struct > platform_device **pdev_out) > > +{ > > + struct platform_device *pdev; > > + struct device_node *remote; > > + > > + remote = of_graph_get_remote_node(dev->of_node, 1, -1); > > + if (!remote) > > + return -ENODEV; > > + > > + if (!of_device_is_compatible(remote, "hdmi-connector")) { > > + of_node_put(remote); > > + return -ENODEV; > > + } > > + > > + pdev = of_find_device_by_node(remote); > > + of_node_put(remote); > > + if (!pdev) > > + return -ENODEV; > > + > > + *pdev_out = pdev; > > + return 0; > > +} > > + > > static int sun8i_dw_hdmi_bind(struct device *dev, struct device *master, > > void *data) > > { > > @@ -151,16 +175,29 @@ static int sun8i_dw_hdmi_bind(struct device *dev, > > struct device *master, return PTR_ERR(hdmi->regulator); > > } > > > > + ret = sun8i_dw_hdmi_find_connector_pdev(dev, &hdmi->connector_pdev); > > + if (!ret) { > > + hdmi->ddc_en = gpiod_get_optional(&hdmi->connector_pdev- > >dev, > > + "ddc-en", > GPIOD_OUT_HIGH); > > + if (IS_ERR(hdmi->ddc_en)) { > > + platform_device_put(hdmi->connector_pdev); > > + dev_err(dev, "Couldn't get ddc-en gpio\n"); > > + return PTR_ERR(hdmi->ddc_en); > > + } > > + } > > + > > ret = regulator_enable(hdmi->regulator); > > if (ret) { > > dev_err(dev, "Failed to enable regulator\n"); > > - return ret; > > + goto err_unref_ddc_en; > > } > > > > + gpiod_set_value(hdmi->ddc_en, 1); > > Why don't you do that inside if clause where hdmi->ddc_en is assigned? It's > not useful otherwise anyway. > > Besides, you would then only need to adjust one goto label in error path. The idea is to enable DDC after enabling the regulator. I don't think it matters for the particular HW that's on Orange Pi 3, and similar Xunlong boards, but this is a fairly generic binding and it makes more sense to power the bus, and then enable whatever aditional circuitry might be there for the IO. I can move sun8i_dw_hdmi_find_connector_pdev lower, but I would then need to disable the regulator in the error path, and I like to keep this order: - parsing DT - enabling actual HW stuff Because parsing is likely to fail with DEFERED_PROBE, because GPIO or whatever else is not yet ready, and this approach avoids enabling/disabling the HW needlessly. > > + > > ret = reset_control_deassert(hdmi->rst_ctrl); > > if (ret) { > > dev_err(dev, "Could not deassert ctrl reset > control\n"); > > - goto err_disable_regulator; > > + goto err_disable_ddc_en; > > } > > > > ret = clk_prepare_enable(hdmi->clk_tmds); > > @@ -213,8 +250,14 @@ static int sun8i_dw_hdmi_bind(struct device *dev, > > struct device *master, clk_disable_unprepare(hdmi->clk_tmds); > > err_assert_ctrl_reset: > > reset_control_assert(hdmi->rst_ctrl); > > -err_disable_regulator: > > +err_disable_ddc_en: > > + gpiod_set_value(hdmi->ddc_en, 0); > > regulator_disable(hdmi->regulator); > > +err_unref_ddc_en: > > + if (hdmi->ddc_en) > > + gpiod_put(hdmi->ddc_en); > > + > > + platform_device_put(hdmi->connector_pdev); > > > > return ret; > > } > > @@ -228,7 +271,13 @@ static void sun8i_dw_hdmi_unbind(struct device *dev, > > struct device *master, sun8i_hdmi_phy_remove(hdmi); > > clk_disable_unprepare(hdmi->clk_tmds); > > reset_control_assert(hdmi->rst_ctrl); > > + gpiod_set_value(hdmi->ddc_en, 0); > > regulator_disable(hdmi->regulator); > > + > > + if (hdmi->ddc_en) > > + gpiod_put(hdmi->ddc_en); > > + > > + platform_device_put(hdmi->connector_pdev); > > } > > > > static const struct component_ops sun8i_dw_hdmi_ops = { > > diff --git a/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h > > b/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h index 720c5aa8adc1..dad66b8301c2 > > 100644 > > --- a/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h > > +++ b/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h > > @@ -9,6 +9,7 @@ > > #include > > #include > > #include > > +#include > > #include > > #include > > #include > > @@ -190,6 +191,8 @@ struct sun8i_dw_hdmi { > > struct regulator *regulator; > > const struct sun8i_dw_hdmi_quirks *quirks; > > struct reset_control *rst_ctrl; > > + struct platform_device *connector_pdev; > > It seems that connector_pdev is needed only during intialization. Why do you > store it? For some reason I thought that I need to keep it to keep the GPIO available, but that's not true. I'll drop it. thank you, Ondrej > Best regards, > Jernej > > > + struct gpio_desc *ddc_en; > > }; > > > > static inline struct sun8i_dw_hdmi *