Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935138AbZLGOIZ (ORCPT ); Mon, 7 Dec 2009 09:08:25 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S935078AbZLGOIY (ORCPT ); Mon, 7 Dec 2009 09:08:24 -0500 Received: from openezx.org ([213.95.46.71]:56158 "EHLO openezx" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S935087AbZLGOIX (ORCPT ); Mon, 7 Dec 2009 09:08:23 -0500 From: Antonio Ospite To: Richard Purdie Cc: Antonio Ospite , Mark Brown , Liam Girdwood , Daniel Ribeiro , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, openezx-devel@lists.openezx.org, Linus Walleij Subject: [PATCH v2] leds: Add LED class driver for regulator driven LEDs. Date: Mon, 7 Dec 2009 15:08:13 +0100 Message-Id: <1260194893-30149-1-git-send-email-ospite@studenti.unina.it> X-Mailer: git-send-email 1.6.5.3 In-Reply-To: <1259775625-25973-1-git-send-email-ospite@studenti.unina.it> References: <1259775625-25973-1-git-send-email-ospite@studenti.unina.it> X-Face: z*RaLf`X<@C75u6Ig9}{oW$H;1_\2t5)({*|jhM/Vb;]yA5\I~93>J<_`<4)A{':UrE Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10064 Lines: 377 This driver provides an interface for controlling LEDs (or vibrators) connected to PMICs for which there is a regulator framework driver. This driver can be used, for instance, to control vibrator on all Motorola EZX phones using the pcap-regulator driver services. Signed-off-by: Antonio Ospite --- Addressed the observations from Mark Brown, Liam Girdwood and Linus Walleij. Patch against: git://git.o-hand.com/linux-rpurdie-leds for-mm Changes since v1: - Use "vled" as supply id. - use regulator_get_exclusive - remove double semicolon - check for LED_OFF instead of 0 - handle regulators which can't change voltages - rename led_regulator_get_vdd to led_regulator_get_voltage - split regulator_led_set_value out of led_work - allow setting an initial brightness value - fix sections markers (__devinit, __devexit, etc.) The only slight doubt I still have is about led_regulator_get_max_brightness(), I have to use regulator_set_voltage() there to tell if a regulator has REGULATOR_CHANGE_VOLTAGE enabled. Regards, Antonio drivers/leds/Kconfig | 6 + drivers/leds/Makefile | 1 + drivers/leds/leds-regulator.c | 242 ++++++++++++++++++++++++++++++++++++++++ include/linux/leds-regulator.h | 46 ++++++++ 4 files changed, 295 insertions(+), 0 deletions(-) create mode 100644 drivers/leds/leds-regulator.c create mode 100644 include/linux/leds-regulator.h diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index f12a996..8a0e1ec 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -229,6 +229,12 @@ config LEDS_PWM help This option enables support for pwm driven LEDs +config LEDS_REGULATOR + tristate "REGULATOR driven LED support" + depends on LEDS_CLASS && REGULATOR + help + This option enables support for regulator driven LEDs. + config LEDS_BD2802 tristate "LED driver for BD2802 RGB LED" depends on LEDS_CLASS && I2C diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 176f0c6..9e63869 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -29,6 +29,7 @@ obj-$(CONFIG_LEDS_DA903X) += leds-da903x.o obj-$(CONFIG_LEDS_WM831X_STATUS) += leds-wm831x-status.o obj-$(CONFIG_LEDS_WM8350) += leds-wm8350.o obj-$(CONFIG_LEDS_PWM) += leds-pwm.o +obj-$(CONFIG_LEDS_REGULATOR) += leds-regulator.o obj-$(CONFIG_LEDS_INTEL_SS4200) += leds-ss4200.o obj-$(CONFIG_LEDS_LT3593) += leds-lt3593.o obj-$(CONFIG_LEDS_ADP5520) += leds-adp5520.o diff --git a/drivers/leds/leds-regulator.c b/drivers/leds/leds-regulator.c new file mode 100644 index 0000000..7f00de3 --- /dev/null +++ b/drivers/leds/leds-regulator.c @@ -0,0 +1,242 @@ +/* + * leds-regulator.c - LED class driver for regulator driven LEDs. + * + * Copyright (C) 2009 Antonio Ospite + * + * Inspired by leds-wm8350 driver. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include +#include +#include +#include +#include +#include +#include + +#define to_regulator_led(led_cdev) \ + container_of(led_cdev, struct regulator_led, cdev) + +struct regulator_led { + struct led_classdev cdev; + enum led_brightness value; + int enabled; + struct mutex mutex; + struct work_struct work; + + struct regulator *vcc; +}; + +static inline int led_regulator_get_max_brightness(struct regulator *supply) +{ + int ret; + int voltage = regulator_list_voltage(supply, 0); + + if (voltage <= 0) + return 1; + + /* even if regulator can't change voltages, + * we still assume it can change status + * and the LED can be turned on and off. + */ + ret = regulator_set_voltage(supply, voltage, voltage); + if (ret < 0) + return 1; + + return regulator_count_voltages(supply); +} + +static int led_regulator_get_voltage(struct regulator *supply, + enum led_brightness brightness) +{ + if (brightness == 0) + return -EINVAL; + + return regulator_list_voltage(supply, brightness - 1); +} + + +static void regulator_led_enable(struct regulator_led *led) +{ + int ret; + + if (led->enabled) + return; + + ret = regulator_enable(led->vcc); + if (ret != 0) { + dev_err(led->cdev.dev, "Failed to enable vcc: %d\n", ret); + return; + } + + led->enabled = 1; +} + +static void regulator_led_disable(struct regulator_led *led) +{ + int ret; + + if (!led->enabled) + return; + + ret = regulator_disable(led->vcc); + if (ret != 0) { + dev_err(led->cdev.dev, "Failed to disable vcc: %d\n", ret); + return; + } + + led->enabled = 0; +} + +static void regulator_led_set_value(struct regulator_led *led) +{ + int voltage; + int ret; + + mutex_lock(&led->mutex); + + if (led->value == LED_OFF) { + regulator_led_disable(led); + goto out; + } + + if (led->cdev.max_brightness > 1) { + voltage = led_regulator_get_voltage(led->vcc, led->value); + dev_dbg(led->cdev.dev, "brightness: %d voltage: %d\n", + led->value, voltage); + + ret = regulator_set_voltage(led->vcc, voltage, voltage); + if (ret != 0) + dev_err(led->cdev.dev, "Failed to set voltage %d: %d\n", + voltage, ret); + } + + regulator_led_enable(led); + +out: + mutex_unlock(&led->mutex); +} + +static void led_work(struct work_struct *work) +{ + struct regulator_led *led; + + led = container_of(work, struct regulator_led, work); + regulator_led_set_value(led); +} + +static void regulator_led_brightness_set(struct led_classdev *led_cdev, + enum led_brightness value) +{ + struct regulator_led *led = to_regulator_led(led_cdev); + + led->value = value; + schedule_work(&led->work); +} + +static int __devinit regulator_led_probe(struct platform_device *pdev) +{ + struct led_regulator_platform_data *pdata = pdev->dev.platform_data; + struct regulator_led *led; + struct regulator *vcc; + int ret = 0; + + if (pdata == NULL) { + dev_err(&pdev->dev, "no platform data\n"); + return -ENODEV; + } + + vcc = regulator_get_exclusive(&pdev->dev, "vled"); + if (IS_ERR(vcc)) { + dev_err(&pdev->dev, "Cannot get vcc for %s\n", pdata->name); + return PTR_ERR(vcc); + } + + led = kzalloc(sizeof(*led), GFP_KERNEL); + if (led == NULL) { + ret = -ENOMEM; + goto err_vcc; + } + + led->cdev.max_brightness = led_regulator_get_max_brightness(vcc); + if (pdata->brightness > led->cdev.max_brightness) { + dev_err(&pdev->dev, "Invalid default brightness %d\n", + pdata->brightness); + ret = -EINVAL; + goto err_led; + } + led->value = pdata->brightness; + + led->cdev.brightness_set = regulator_led_brightness_set; + led->cdev.name = pdata->name; + led->cdev.flags |= LED_CORE_SUSPENDRESUME; + led->vcc = vcc; + + mutex_init(&led->mutex); + INIT_WORK(&led->work, led_work); + + platform_set_drvdata(pdev, led); + + ret = led_classdev_register(&pdev->dev, &led->cdev); + if (ret < 0) { + cancel_work_sync(&led->work); + goto err_led; + } + + /* to expose the default value to userspace */ + led->cdev.brightness = led->value; + + /* Set the default led status */ + regulator_led_set_value(led); + + return 0; + +err_led: + kfree(led); +err_vcc: + regulator_put(vcc); + return ret; +} + +static int __devexit regulator_led_remove(struct platform_device *pdev) +{ + struct regulator_led *led = platform_get_drvdata(pdev); + + led_classdev_unregister(&led->cdev); + cancel_work_sync(&led->work); + regulator_led_disable(led); + regulator_put(led->vcc); + kfree(led); + return 0; +} + +static struct platform_driver regulator_led_driver = { + .driver = { + .name = "leds-regulator", + .owner = THIS_MODULE, + }, + .probe = regulator_led_probe, + .remove = __devexit_p(regulator_led_remove), +}; + +static int __init regulator_led_init(void) +{ + return platform_driver_register(®ulator_led_driver); +} +module_init(regulator_led_init); + +static void __exit regulator_led_exit(void) +{ + platform_driver_unregister(®ulator_led_driver); +} +module_exit(regulator_led_exit); + +MODULE_AUTHOR("Antonio Ospite "); +MODULE_DESCRIPTION("Regulator driven LED driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:leds-regulator"); diff --git a/include/linux/leds-regulator.h b/include/linux/leds-regulator.h new file mode 100644 index 0000000..a40275a --- /dev/null +++ b/include/linux/leds-regulator.h @@ -0,0 +1,46 @@ +/* + * leds-regulator.h - platform data structure for regulator driven LEDs. + * + * Copyright (C) 2009 Antonio Ospite + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#ifndef __LINUX_LEDS_REGULATOR_H +#define __LINUX_LEDS_REGULATOR_H + +/* + * Use "vled" as supply id when declaring the regulator consumer: + * + * static struct regulator_consumer_supply pcap_regulator_VVIB_consumers [] = { + * { .dev_name = "leds-regulator.0", supply = "vled" }, + * }; + * + * If you have several regulator driven LEDs, you can append a numerical id to + * .dev_name as done above, and use the same id when declaring the platform + * device: + * + * static struct led_regulator_platform_data a780_vibrator_data = { + * .name = "a780::vibrator", + * }; + * + * static struct platform_device a780_vibrator = { + * .name = "leds-regulator", + * .id = 0, + * .dev = { + * .platform_data = &a780_vibrator_data, + * }, + * }; + */ + +#include + +struct led_regulator_platform_data { + char *name; /* LED name as expected by LED class */ + enum led_brightness brightness; /* initial brightness value */ +}; + +#endif /* __LINUX_LEDS_REGULATOR_H */ -- 1.6.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/