Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754803AbcKBBd3 (ORCPT ); Tue, 1 Nov 2016 21:33:29 -0400 Received: from smtp.csie.ntu.edu.tw ([140.112.30.61]:53480 "EHLO smtp.csie.ntu.edu.tw" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752661AbcKBBd1 (ORCPT ); Tue, 1 Nov 2016 21:33:27 -0400 MIME-Version: 1.0 In-Reply-To: <20161031062836.mnzdprqfezrfkx4g@rob-hp-laptop> References: <20161029110611.28951-1-wens@csie.org> <20161029110611.28951-2-wens@csie.org> <20161031062836.mnzdprqfezrfkx4g@rob-hp-laptop> From: Chen-Yu Tsai Date: Wed, 2 Nov 2016 09:33:01 +0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [linux-sunxi] Re: [PATCH v3 1/2] drm/bridge: dumb-vga-dac: Support a VDD regulator supply To: Rob Herring Cc: Chen-Yu Tsai , Maxime Ripard , David Airlie , Mark Rutland , 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: 4111 Lines: 121 On Mon, Oct 31, 2016 at 2:28 PM, Rob Herring wrote: > On Sat, Oct 29, 2016 at 07:06:10PM +0800, 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 >> --- >> .../bindings/display/bridge/dumb-vga-dac.txt | 2 ++ > > For the binding, > > Acked-by: Rob Herring > > One code comment below... > >> 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..59781e031220 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 +126,33 @@ 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; >> + >> + if (!IS_ERR(vga->vdd)) { > > if (IS_ERR()) > return; > > ...will save some intentation. I thought about that, though if someone were to add more stuff to this, such as an enable GPIO, they might have to rework it. A standalone block of code would be easier to work with. I'm OK either way though. ChenYu > >> + ret = regulator_enable(vga->vdd); >> + >> + if (ret) { >> + DRM_ERROR("Failed to enable vdd regulator: %d\n", ret); >> + return; >> + } >> + } >> +} >> + >> +static void dumb_vga_disable(struct drm_bridge *bridge) >> +{ >> + struct dumb_vga *vga = drm_bridge_to_dumb_vga(bridge); >> + >> + if (!IS_ERR(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 +196,14 @@ 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; >> + 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) { >> -- >> 2.9.3 >> > > -- > You received this message because you are subscribed to the Google Groups "linux-sunxi" group. > To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscribe@googlegroups.com. > For more options, visit https://groups.google.com/d/optout.