From patchwork Sun Jul 2 11:06:13 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Young X-Patchwork-Id: 783176 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3x0nhv7438z9sNw for ; Sun, 2 Jul 2017 21:14:23 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751973AbdGBLOV (ORCPT ); Sun, 2 Jul 2017 07:14:21 -0400 Received: from gofer.mess.org ([88.97.38.141]:37465 "EHLO gofer.mess.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752029AbdGBLOU (ORCPT ); Sun, 2 Jul 2017 07:14:20 -0400 Received: by gofer.mess.org (Postfix, from userid 1000) id DA1DF6065F; Sun, 2 Jul 2017 12:06:13 +0100 (BST) From: Sean Young To: linux-media@vger.kernel.org, devicetree@vger.kernel.org, Rob Herring Cc: Pavel Machek , Ivaylo Dimitrov , Timo Kokkonen Subject: [PATCH 4/4] [media] rc: pwm-ir-tx: add new driver Date: Sun, 2 Jul 2017 12:06:13 +0100 Message-Id: <88fa0219db3388fad7bcc7b20cf30dd41e763aee.1498992850.git.sean@mess.org> X-Mailer: git-send-email 2.1.4 In-Reply-To: References: Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org This is new driver which uses pwm, so it is more power-efficient than the bit banging gpio-ir-tx driver. Signed-off-by: Sean Young --- .../devicetree/bindings/leds/irled/pwm-ir-tx.txt | 13 ++ drivers/media/rc/Kconfig | 12 ++ drivers/media/rc/Makefile | 1 + drivers/media/rc/pwm-ir-tx.c | 165 +++++++++++++++++++++ 4 files changed, 191 insertions(+) create mode 100644 Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt create mode 100644 drivers/media/rc/pwm-ir-tx.c diff --git a/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt b/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt new file mode 100644 index 0000000..6887a71 --- /dev/null +++ b/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt @@ -0,0 +1,13 @@ +Device tree bindings for IR LED connected through pwm pin which is used as +IR transmitter. + +Required properties: +- compatible: should be "pwm-ir-tx". +- pwms : PWM property to point to the PWM device (phandle)/port (id) and to + specify the period time to be used: <&phandle id period_ns>; + +Example: + irled { + compatible = "pwm-ir-tx"; + pwms = <&pwm0 0 10000000>; + }; diff --git a/drivers/media/rc/Kconfig b/drivers/media/rc/Kconfig index ad54011..c5338e3 100644 --- a/drivers/media/rc/Kconfig +++ b/drivers/media/rc/Kconfig @@ -399,6 +399,18 @@ config IR_GPIO_TX To compile this driver as a module, choose M here: the module will be called gpio-ir-tx. +config IR_PWM_TX + tristate "PWM IR transmitter" + depends on RC_CORE + depends on LIRC + depends on PWM + ---help--- + Say Y if you want to use a PWM based IR transmitter. This is + more power efficient than the bit banging gpio driver. + + To compile this driver as a module, choose M here: the module will + be called pwm-ir-tx. + config RC_ST tristate "ST remote control receiver" depends on RC_CORE diff --git a/drivers/media/rc/Makefile b/drivers/media/rc/Makefile index 3e64a4e..466c402 100644 --- a/drivers/media/rc/Makefile +++ b/drivers/media/rc/Makefile @@ -33,6 +33,7 @@ obj-$(CONFIG_IR_WINBOND_CIR) += winbond-cir.o obj-$(CONFIG_RC_LOOPBACK) += rc-loopback.o obj-$(CONFIG_IR_GPIO_CIR) += gpio-ir-recv.o obj-$(CONFIG_IR_GPIO_TX) += gpio-ir-tx.o +obj-$(CONFIG_IR_PWM_TX) += pwm-ir-tx.o obj-$(CONFIG_IR_IGORPLUGUSB) += igorplugusb.o obj-$(CONFIG_IR_IGUANA) += iguanair.o obj-$(CONFIG_IR_TTUSBIR) += ttusbir.o diff --git a/drivers/media/rc/pwm-ir-tx.c b/drivers/media/rc/pwm-ir-tx.c new file mode 100644 index 0000000..1ab10b4 --- /dev/null +++ b/drivers/media/rc/pwm-ir-tx.c @@ -0,0 +1,165 @@ +/* + * Copyright (C) 2017 Sean Young + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define DRIVER_NAME "pwm-ir-tx" +#define DEVICE_NAME "PWM IR Transmitter" + +struct pwm_ir { + struct pwm_device *pwm; + unsigned int carrier; + unsigned int duty_cycle; + /* One transmission at a time */ + struct mutex lock; +}; + +static const struct of_device_id pwm_ir_of_match[] = { + { .compatible = "pwm-ir-tx", }, + { }, +}; +MODULE_DEVICE_TABLE(of, pwm_ir_of_match); + +static int pwm_ir_set_duty_cycle(struct rc_dev *dev, u32 duty_cycle) +{ + struct pwm_ir *pwm_ir = dev->priv; + + pwm_ir->duty_cycle = duty_cycle; + + return 0; +} + +static int pwm_ir_set_carrier(struct rc_dev *dev, u32 carrier) +{ + struct pwm_ir *pwm_ir = dev->priv; + + if (!carrier) + return -EINVAL; + + pwm_ir->carrier = carrier; + + return 0; +} + +static int pwm_ir_tx(struct rc_dev *dev, unsigned int *txbuf, + unsigned int count) +{ + struct pwm_ir *pwm_ir = dev->priv; + struct pwm_device *pwm = pwm_ir->pwm; + int i, duty, period; + ktime_t edge; + s64 delta; + + if (mutex_lock_interruptible(&pwm_ir->lock)) + return -ERESTARTSYS; + + period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, pwm_ir->carrier); + duty = DIV_ROUND_CLOSEST(pwm_ir->duty_cycle * period, 100); + + pwm_config(pwm, duty, period); + + edge = ktime_get(); + + for (i = 0; i < count; i++) { + if (i % 2) // space + pwm_disable(pwm); + else + pwm_enable(pwm); + + edge = ktime_add_us(edge, txbuf[i]); + delta = ktime_us_delta(edge, ktime_get()); + if (delta > 0) + usleep_range(delta, delta + 10); + } + + pwm_disable(pwm); + + mutex_unlock(&pwm_ir->lock); + + return count; +} + +static int pwm_ir_probe(struct platform_device *pdev) +{ + struct pwm_ir *pwm_ir; + struct rc_dev *rcdev; + int rc; + + pwm_ir = devm_kzalloc(&pdev->dev, sizeof(*pwm_ir), GFP_KERNEL); + if (!pwm_ir) + return -ENOMEM; + + pwm_ir->pwm = devm_pwm_get(&pdev->dev, NULL); + if (IS_ERR(pwm_ir->pwm)) + return PTR_ERR(pwm_ir->pwm); + + pwm_ir->carrier = 38000; + pwm_ir->duty_cycle = 50; + mutex_init(&pwm_ir->lock); + + rcdev = devm_rc_allocate_device(&pdev->dev, RC_DRIVER_IR_RAW_TX); + if (!rcdev) + return -ENOMEM; + + rcdev->priv = pwm_ir; + rcdev->driver_name = DRIVER_NAME; + rcdev->device_name = DEVICE_NAME; + rcdev->tx_ir = pwm_ir_tx; + rcdev->s_tx_duty_cycle = pwm_ir_set_duty_cycle; + rcdev->s_tx_carrier = pwm_ir_set_carrier; + + rc = devm_rc_register_device(&pdev->dev, rcdev); + if (rc < 0) { + dev_err(&pdev->dev, "failed to register rc device\n"); + return rc; + } + + platform_set_drvdata(pdev, pwm_ir); + + return 0; +} + +#ifdef CONFIG_PM +static int pwm_ir_suspend(struct platform_device *dev, pm_message_t state) +{ + struct pwm_ir *pwm_ir = platform_get_drvdata(dev); + + if (mutex_is_locked(&pwm_ir->lock)) + return -EAGAIN; + + return 0; +} +#else +#define pwm_ir_suspend NULL +#endif + +static struct platform_driver pwm_ir_driver = { + .probe = pwm_ir_probe, + .suspend = pwm_ir_suspend, + .driver = { + .name = DRIVER_NAME, + .of_match_table = of_match_ptr(pwm_ir_of_match), + }, +}; +module_platform_driver(pwm_ir_driver); + +MODULE_DESCRIPTION("PWM IR Transmitter"); +MODULE_AUTHOR("Sean Young "); +MODULE_LICENSE("GPL");