Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932205AbcKQH4Q (ORCPT ); Thu, 17 Nov 2016 02:56:16 -0500 Received: from smtp.csie.ntu.edu.tw ([140.112.30.61]:46424 "EHLO smtp.csie.ntu.edu.tw" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751609AbcKQH4O (ORCPT ); Thu, 17 Nov 2016 02:56:14 -0500 MIME-Version: 1.0 In-Reply-To: <31b8b5b9-9621-286a-7649-cc999ab020da@codeaurora.org> References: <20161116154232.872-1-wens@csie.org> <20161116154232.872-2-wens@csie.org> <31b8b5b9-9621-286a-7649-cc999ab020da@codeaurora.org> From: Chen-Yu Tsai Date: Thu, 17 Nov 2016 15:55:47 +0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v4 1/2] drm/bridge: dumb-vga-dac: Support a VDD regulator supply To: Archit Taneja Cc: Chen-Yu Tsai , Maxime Ripard , David Airlie , dri-devel , linux-arm-kernel , linux-kernel , devicetree , linux-sunxi Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3817 Lines: 126 On Thu, Nov 17, 2016 at 3:48 PM, Archit Taneja wrote: > 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? Yes, please! Thanks ChenYu > > 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