/* * leds-ns2.c - Driver for the Network Space v2 (and parents) dual-GPIO LED * * Copyright (C) 2010 LaCie * * Author: Simon Guinot <sguinot@lacie.com> * * Based on leds-gpio.c by Raphael Assenat <raph@8d.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, 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. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include <linux/kernel.h> #include <linux/init.h> #include <linux/platform_device.h> #include <linux/slab.h> #include <linux/gpio.h> #include <linux/leds.h> #include <mach/leds-ns2.h> /* * The Network Space v2 dual-GPIO LED is wired to a CPLD and can blink in * relation with the SATA activity. This capability is exposed through the * "sata" sysfs attribute. * * The following array detail the different LED registers and the combination * of their possible values: * * cmd_led | slow_led | /SATA active | LED state * | | | * 1 | 0 | x | off * - | 1 | x | on * 0 | 0 | 1 | on * 0 | 0 | 0 | blink (rate 300ms) */ enum ns2_led_modes { NS_V2_LED_OFF, NS_V2_LED_ON, NS_V2_LED_SATA, }; struct ns2_led_mode_value { enum ns2_led_modes mode; int cmd_level; int slow_level; }; static struct ns2_led_mode_value ns2_led_modval[] = { { NS_V2_LED_OFF , 1, 0 }, { NS_V2_LED_ON , 0, 1 }, { NS_V2_LED_ON , 1, 1 }, { NS_V2_LED_SATA, 0, 0 }, }; struct ns2_led_data { struct led_classdev cdev; unsigned cmd; unsigned slow; unsigned char sata; /* True when SATA mode active. */ rwlock_t rw_lock; /* Lock GPIOs. */ }; static int ns2_led_get_mode(struct ns2_led_data *led_dat, enum ns2_led_modes *mode) { int i; int ret = -EINVAL; int cmd_level; int slow_level; read_lock(&led_dat->rw_lock); cmd_level = gpio_get_value(led_dat->cmd); slow_level = gpio_get_value(led_dat->slow); for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) { if (cmd_level == ns2_led_modval[i].cmd_level && slow_level == ns2_led_modval[i].slow_level) { *mode = ns2_led_modval[i].mode; ret = 0; break; } } read_unlock(&led_dat->rw_lock); return ret; } static void ns2_led_set_mode(struct ns2_led_data *led_dat, enum ns2_led_modes mode) { int i; write_lock(&led_dat->rw_lock); for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) { if (mode == ns2_led_modval[i].mode) { gpio_set_value(led_dat->cmd, ns2_led_modval[i].cmd_level); gpio_set_value(led_dat->slow, ns2_led_modval[i].slow_level); } } write_unlock(&led_dat->rw_lock); } static void ns2_led_set(struct led_classdev *led_cdev, enum led_brightness value) { struct ns2_led_data *led_dat = container_of(led_cdev, struct ns2_led_data, cdev); enum ns2_led_modes mode; if (value == LED_OFF) mode = NS_V2_LED_OFF; else if (led_dat->sata) mode = NS_V2_LED_SATA; else mode = NS_V2_LED_ON; ns2_led_set_mode(led_dat, mode); } static ssize_t ns2_led_sata_store(struct device *dev, struct device_attribute *attr, const char *buff, size_t count) { int ret; unsigned long enable; enum ns2_led_modes mode; struct ns2_led_data *led_dat = dev_get_drvdata(dev); ret = strict_strtoul(buff, 10, &enable); if (ret < 0) return ret; enable = !!enable; if (led_dat->sata == enable) return count; ret = ns2_led_get_mode(led_dat, &mode); if (ret < 0) return ret; if (enable && mode == NS_V2_LED_ON) ns2_led_set_mode(led_dat, NS_V2_LED_SATA); if (!enable && mode == NS_V2_LED_SATA) ns2_led_set_mode(led_dat, NS_V2_LED_ON); led_dat->sata = enable; return count; } static ssize_t ns2_led_sata_show(struct device *dev, struct device_attribute *attr, char *buf) { struct ns2_led_data *led_dat = dev_get_drvdata(dev); return sprintf(buf, "%d\n", led_dat->sata); } static DEVICE_ATTR(sata, 0644, ns2_led_sata_show, ns2_led_sata_store); static int __devinit create_ns2_led(struct platform_device *pdev, struct ns2_led_data *led_dat, const struct ns2_led *template) { int ret; enum ns2_led_modes mode; ret = gpio_request(template->cmd, template->name); if (ret == 0) { ret = gpio_direction_output(template->cmd, gpio_get_value(template->cmd)); if (ret) gpio_free(template->cmd); } if (ret) { dev_err(&pdev->dev, "%s: failed to setup command GPIO\n", template->name); } ret = gpio_request(template->slow, template->name); if (ret == 0) { ret = gpio_direction_output(template->slow, gpio_get_value(template->slow)); if (ret) gpio_free(template->slow); } if (ret) { dev_err(&pdev->dev, "%s: failed to setup slow GPIO\n", template->name); goto err_free_cmd; } rwlock_init(&led_dat->rw_lock); led_dat->cdev.name = template->name; led_dat->cdev.default_trigger = template->default_trigger; led_dat->cdev.blink_set = NULL; led_dat->cdev.brightness_set = ns2_led_set; led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME; led_dat->cmd = template->cmd; led_dat->slow = template->slow; ret = ns2_led_get_mode(led_dat, &mode); if (ret < 0) goto err_free_slow; /* Set LED initial state. */ led_dat->sata = (mode == NS_V2_LED_SATA) ? 1 : 0; led_dat->cdev.brightness = (mode == NS_V2_LED_OFF) ? LED_OFF : LED_FULL; ret = led_classdev_register(&pdev->dev, &led_dat->cdev); if (ret < 0) goto err_free_slow; dev_set_drvdata(led_dat->cdev.dev, led_dat); ret = device_create_file(led_dat->cdev.dev, &dev_attr_sata); if (ret < 0) goto err_free_cdev; return 0; err_free_cdev: led_classdev_unregister(&led_dat->cdev); err_free_slow: gpio_free(led_dat->slow); err_free_cmd: gpio_free(led_dat->cmd); return ret; } static void __devexit delete_ns2_led(struct ns2_led_data *led_dat) { device_remove_file(led_dat->cdev.dev, &dev_attr_sata); led_classdev_unregister(&led_dat->cdev); gpio_free(led_dat->cmd); gpio_free(led_dat->slow); } static int __devinit ns2_led_probe(struct platform_device *pdev) { struct ns2_led_platform_data *pdata = pdev->dev.platform_data; struct ns2_led_data *leds_data; int i; int ret; if (!pdata) return -EINVAL; leds_data = kzalloc(sizeof(struct ns2_led_data) * pdata->num_leds, GFP_KERNEL); if (!leds_data) return -ENOMEM; for (i = 0; i < pdata->num_leds; i++) { ret = create_ns2_led(pdev, &leds_data[i], &pdata->leds[i]); if (ret < 0) goto err; } platform_set_drvdata(pdev, leds_data); return 0; err: for (i = i - 1; i >= 0; i--) delete_ns2_led(&leds_data[i]); kfree(leds_data); return ret; } static int __devexit ns2_led_remove(struct platform_device *pdev) { int i; struct ns2_led_platform_data *pdata = pdev->dev.platform_data; struct ns2_led_data *leds_data; leds_data = platform_get_drvdata(pdev); for (i = 0; i < pdata->num_leds; i++) delete_ns2_led(&leds_data[i]); kfree(leds_data); platform_set_drvdata(pdev, NULL); return 0; } static struct platform_driver ns2_led_driver = { .probe = ns2_led_probe, .remove = __devexit_p(ns2_led_remove), .driver = { .name = "leds-ns2", .owner = THIS_MODULE, }, }; MODULE_ALIAS("platform:leds-ns2"); static int __init ns2_led_init(void) { return platform_driver_register(&ns2_led_driver); } static void __exit ns2_led_exit(void) { platform_driver_unregister(&ns2_led_driver); } module_init(ns2_led_init); module_exit(ns2_led_exit); MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>"); MODULE_DESCRIPTION("Network Space v2 LED driver"); MODULE_LICENSE("GPL");