From patchwork Wed Aug 2 08:42:41 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans Verkuil X-Patchwork-Id: 9876279 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id A56E26037D for ; Wed, 2 Aug 2017 08:42:57 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9400A28757 for ; Wed, 2 Aug 2017 08:42:57 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8906B28753; Wed, 2 Aug 2017 08:42:57 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 0A04928757 for ; Wed, 2 Aug 2017 08:42:57 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 481086EFE9; Wed, 2 Aug 2017 08:42:52 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from lb1-smtp-cloud7.xs4all.net (lb1-smtp-cloud7.xs4all.net [194.109.24.24]) by gabe.freedesktop.org (Postfix) with ESMTPS id 28A216EFE2 for ; Wed, 2 Aug 2017 08:42:48 +0000 (UTC) Received: from tschai.fritz.box ([212.251.195.8]) by smtp-cloud7.xs4all.net with ESMTPA id cpEodNfHAZNWkcpEsdA86A; Wed, 02 Aug 2017 10:42:46 +0200 From: Hans Verkuil To: linux-media@vger.kernel.org Subject: [PATCH 2/3] cec-gpio: add HDMI CEC GPIO driver Date: Wed, 2 Aug 2017 10:42:41 +0200 Message-Id: <20170802084242.14947-3-hverkuil@xs4all.nl> X-Mailer: git-send-email 2.13.2 In-Reply-To: <20170802084242.14947-1-hverkuil@xs4all.nl> References: <20170802084242.14947-1-hverkuil@xs4all.nl> X-CMAE-Envelope: MS4wfDirG5g1n1Fx2maK+vooSisFpx8Kk2iOEB8Kn/EpdMBG6vhwH4a434Q3APkgQJdbGe4FY84T1ACkNPbRIqVhr1O2ryLzGqLbaTj5TD07lB6HSRD+w6VX BfswpEvDNFAtASedet52/hUIMwmLsEL/ciD0jy1Q1tA0HjrVNujb8olHuo9xUNC3GiW7/Xhsu8LCiuB2CzfLygoyW70+N3Y9PfEVwMZ02YaibPy2P5Zov7L1 QRnUsG6HV43SROP36Zx1AFySYaxKTf7UlsrVwFK/AMLrr12SqyiN5PSSauOpfxWIds1wDwRMyu1JA2KJZxMisg== Cc: Hans Verkuil , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Hans Verkuil Add a simple HDMI CEC GPIO driver that sits on top of the cec-pin framework. While I have heard of SoCs that use the GPIO pin for CEC (apparently an early RockChip SoC used that), the main use-case of this driver is to function as a debugging tool. By connecting the CEC line to a GPIO pin on a Raspberry Pi 3 for example it turns it into a CEC debugger and protocol analyzer. With 'cec-ctl --monitor-pin' the CEC traffic can be analyzed. But of course it can also be used with any hardware project where the HDMI CEC pin is hooked up to a pull-up gpio pin. Signed-off-by: Hans Verkuil --- drivers/media/platform/Kconfig | 10 ++ drivers/media/platform/Makefile | 2 + drivers/media/platform/cec-gpio/Makefile | 1 + drivers/media/platform/cec-gpio/cec-gpio.c | 190 +++++++++++++++++++++++++++++ 4 files changed, 203 insertions(+) create mode 100644 drivers/media/platform/cec-gpio/Makefile create mode 100644 drivers/media/platform/cec-gpio/cec-gpio.c diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig index 0c741d12dbc9..681507727259 100644 --- a/drivers/media/platform/Kconfig +++ b/drivers/media/platform/Kconfig @@ -537,6 +537,16 @@ menuconfig CEC_PLATFORM_DRIVERS if CEC_PLATFORM_DRIVERS +config CEC_GPIO + tristate "Generic GPIO-based CEC driver" + depends on PREEMPT + select CEC_CORE + select CEC_PIN + ---help--- + This is a generic GPIO-based CEC driver. + The CEC bus is present in the HDMI connector and enables communication + between compatible devices. + config VIDEO_SAMSUNG_S5P_CEC tristate "Samsung S5P CEC driver" depends on PLAT_S5P || ARCH_EXYNOS || COMPILE_TEST diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile index 9beadc760467..d01cc1886ad1 100644 --- a/drivers/media/platform/Makefile +++ b/drivers/media/platform/Makefile @@ -26,6 +26,8 @@ obj-$(CONFIG_VIDEO_CODA) += coda/ obj-$(CONFIG_VIDEO_SH_VEU) += sh_veu.o +obj-$(CONFIG_CEC_GPIO) += cec-gpio/ + obj-$(CONFIG_VIDEO_MEM2MEM_DEINTERLACE) += m2m-deinterlace.o obj-$(CONFIG_VIDEO_MUX) += video-mux.o diff --git a/drivers/media/platform/cec-gpio/Makefile b/drivers/media/platform/cec-gpio/Makefile new file mode 100644 index 000000000000..e82b258afa55 --- /dev/null +++ b/drivers/media/platform/cec-gpio/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_CEC_GPIO) += cec-gpio.o diff --git a/drivers/media/platform/cec-gpio/cec-gpio.c b/drivers/media/platform/cec-gpio/cec-gpio.c new file mode 100644 index 000000000000..43e1d447ad98 --- /dev/null +++ b/drivers/media/platform/cec-gpio/cec-gpio.c @@ -0,0 +1,190 @@ +/* + * Copyright 2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved. + * + * This program is free software; you may redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +struct cec_gpio { + struct cec_adapter *adap; + struct device *dev; + int gpio; + int irq; + bool is_low; + bool have_irq; +}; + +static bool cec_gpio_read(struct cec_adapter *adap) +{ + struct cec_gpio *cec = cec_get_drvdata(adap); + + if (cec->is_low) + return false; + return gpio_get_value(cec->gpio); +} + +static void cec_gpio_high(struct cec_adapter *adap) +{ + struct cec_gpio *cec = cec_get_drvdata(adap); + + if (!cec->is_low) + return; + cec->is_low = false; + gpio_direction_input(cec->gpio); +} + +static void cec_gpio_low(struct cec_adapter *adap) +{ + struct cec_gpio *cec = cec_get_drvdata(adap); + + if (cec->is_low) + return; + if (WARN_ON_ONCE(cec->have_irq)) + free_irq(cec->irq, cec); + cec->have_irq = false; + cec->is_low = true; + gpio_direction_output(cec->gpio, 0); +} + +static irqreturn_t cec_gpio_irq_handler(int irq, void *priv) +{ + struct cec_gpio *cec = priv; + + cec_pin_changed(cec->adap, gpio_get_value(cec->gpio)); + return IRQ_HANDLED; +} + +static bool cec_gpio_enable_irq(struct cec_adapter *adap) +{ + struct cec_gpio *cec = cec_get_drvdata(adap); + + if (request_irq(cec->irq, cec_gpio_irq_handler, + IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, + adap->name, cec)) + return false; + cec->have_irq = true; + return true; +} + +static void cec_gpio_disable_irq(struct cec_adapter *adap) +{ + struct cec_gpio *cec = cec_get_drvdata(adap); + + if (cec->have_irq) + free_irq(cec->irq, cec); + cec->have_irq = false; +} + +static void cec_gpio_status(struct cec_adapter *adap, struct seq_file *file) +{ + struct cec_gpio *cec = cec_get_drvdata(adap); + + seq_printf(file, "mode: %s\n", cec->is_low ? "low-drive" : "read"); + if (cec->have_irq) + seq_printf(file, "using irq: %d\n", cec->irq); +} + +static void cec_gpio_free(struct cec_adapter *adap) +{ + struct cec_gpio *cec = cec_get_drvdata(adap); + + if (cec->have_irq) + cec_gpio_disable_irq(adap); +} + +static const struct cec_pin_ops cec_gpio_pin_ops = { + .read = cec_gpio_read, + .low = cec_gpio_low, + .high = cec_gpio_high, + .enable_irq = cec_gpio_enable_irq, + .disable_irq = cec_gpio_disable_irq, + .status = cec_gpio_status, + .free = cec_gpio_free, +}; + +static int cec_gpio_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + enum of_gpio_flags hpd_gpio_flags; + struct cec_gpio *cec; + int ret; + + cec = devm_kzalloc(dev, sizeof(*cec), GFP_KERNEL); + if (!cec) + return -ENOMEM; + + cec->gpio = of_get_named_gpio_flags(dev->of_node, + "gpio", 0, &hpd_gpio_flags); + if (cec->gpio < 0) + return cec->gpio; + + cec->irq = gpio_to_irq(cec->gpio); + gpio_direction_input(cec->gpio); + cec->dev = dev; + + cec->adap = cec_pin_allocate_adapter(&cec_gpio_pin_ops, + cec, pdev->name, CEC_CAP_TRANSMIT | CEC_CAP_LOG_ADDRS | + CEC_CAP_PASSTHROUGH | CEC_CAP_RC | CEC_CAP_PHYS_ADDR | + CEC_CAP_MONITOR_ALL | CEC_CAP_MONITOR_PIN); + if (IS_ERR(cec->adap)) + return PTR_ERR(cec->adap); + + ret = cec_register_adapter(cec->adap, &pdev->dev); + if (ret) { + cec_delete_adapter(cec->adap); + return ret; + } + + platform_set_drvdata(pdev, cec); + return 0; +} + +static int cec_gpio_remove(struct platform_device *pdev) +{ + struct cec_gpio *cec = platform_get_drvdata(pdev); + + cec_unregister_adapter(cec->adap); + return 0; +} + +static const struct of_device_id cec_gpio_match[] = { + { + .compatible = "cec-gpio", + }, + {}, +}; +MODULE_DEVICE_TABLE(of, cec_gpio_match); + +static struct platform_driver cec_gpio_pdrv = { + .probe = cec_gpio_probe, + .remove = cec_gpio_remove, + .driver = { + .name = "cec-gpio", + .of_match_table = cec_gpio_match, + }, +}; + +module_platform_driver(cec_gpio_pdrv); + +MODULE_AUTHOR("Hans Verkuil "); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("CEC GPIO driver");