From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752739AbcKQHtJ (ORCPT ); Thu, 17 Nov 2016 02:49:09 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:35636 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752301AbcKQHtG (ORCPT ); Thu, 17 Nov 2016 02:49:06 -0500 DMARC-Filter: OpenDMARC Filter v1.3.1 smtp.codeaurora.org 685EC6022D Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=pass smtp.mailfrom=architt@codeaurora.org Subject: Re: [PATCH v4 1/2] drm/bridge: dumb-vga-dac: Support a VDD regulator supply To: Chen-Yu Tsai , Maxime Ripard , David Airlie References: <20161116154232.872-1-wens@csie.org> <20161116154232.872-2-wens@csie.org> Cc: dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-sunxi@googlegroups.com From: Archit Taneja Message-ID: <31b8b5b9-9621-286a-7649-cc999ab020da@codeaurora.org> Date: Thu, 17 Nov 2016 13:18:58 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <20161116154232.872-2-wens@csie.org> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Thanks for the patch. On 11/16/2016 09:12 PM, Chen-Yu Tsai wrote: > Some dumb VGA DACs are active components which require external power. > Add support for specifying a regulator as its power supply. > > Signed-off-by: Chen-Yu Tsai > Acked-by: Rob Herring > --- > .../bindings/display/bridge/dumb-vga-dac.txt | 2 ++ > drivers/gpu/drm/bridge/dumb-vga-dac.c | 35 ++++++++++++++++++++++ > 2 files changed, 37 insertions(+) > > diff --git a/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt b/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt > index 003bc246a270..164cbb15f04c 100644 > --- a/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt > +++ b/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt > @@ -16,6 +16,8 @@ graph bindings specified in Documentation/devicetree/bindings/graph.txt. > - Video port 0 for RGB input > - Video port 1 for VGA output > > +Optional properties: > +- vdd-supply: Power supply for DAC > > Example > ------- > diff --git a/drivers/gpu/drm/bridge/dumb-vga-dac.c b/drivers/gpu/drm/bridge/dumb-vga-dac.c > index afec232185a7..15b549f94307 100644 > --- a/drivers/gpu/drm/bridge/dumb-vga-dac.c > +++ b/drivers/gpu/drm/bridge/dumb-vga-dac.c > @@ -12,6 +12,7 @@ > > #include > #include > +#include > > #include > #include > @@ -23,6 +24,7 @@ struct dumb_vga { > struct drm_connector connector; > > struct i2c_adapter *ddc; > + struct regulator *vdd; > }; > > static inline struct dumb_vga * > @@ -124,8 +126,32 @@ static int dumb_vga_attach(struct drm_bridge *bridge) > return 0; > } > > +static void dumb_vga_enable(struct drm_bridge *bridge) > +{ > + struct dumb_vga *vga = drm_bridge_to_dumb_vga(bridge); > + int ret = 0; > + > + if (vga->vdd) > + ret = regulator_enable(vga->vdd); > + > + if (ret) { > + DRM_ERROR("Failed to enable vdd regulator: %d\n", ret); > + return; We don't need this return for now. If you're okay with it, can I fix this and queue to misc? Thanks, Archit > + } > +} > + > +static void dumb_vga_disable(struct drm_bridge *bridge) > +{ > + struct dumb_vga *vga = drm_bridge_to_dumb_vga(bridge); > + > + if (vga->vdd) > + regulator_disable(vga->vdd); > +} > + > static const struct drm_bridge_funcs dumb_vga_bridge_funcs = { > .attach = dumb_vga_attach, > + .enable = dumb_vga_enable, > + .disable = dumb_vga_disable, > }; > > static struct i2c_adapter *dumb_vga_retrieve_ddc(struct device *dev) > @@ -169,6 +195,15 @@ static int dumb_vga_probe(struct platform_device *pdev) > return -ENOMEM; > platform_set_drvdata(pdev, vga); > > + vga->vdd = devm_regulator_get_optional(&pdev->dev, "vdd"); > + if (IS_ERR(vga->vdd)) { > + ret = PTR_ERR(vga->vdd); > + if (ret == -EPROBE_DEFER) > + return -EPROBE_DEFER; > + vga->vdd = NULL; > + dev_dbg(&pdev->dev, "No vdd regulator found: %d\n", ret); > + } > + > vga->ddc = dumb_vga_retrieve_ddc(&pdev->dev); > if (IS_ERR(vga->ddc)) { > if (PTR_ERR(vga->ddc) == -ENODEV) { > -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project