/* * 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 <linux/module.h> #include <linux/platform_data/leds-kirkwood-ns2.h> #include <linux/of.h> #include <linux/of_gpio.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_irq(&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_irq(&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; unsigned long flags; write_lock_irqsave(&led_dat->rw_lock, flags); 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_irqrestore(&led_dat->rw_lock, flags); } 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) { struct led_classdev *led_cdev = dev_get_drvdata(dev); struct ns2_led_data *led_dat = container_of(led_cdev, struct ns2_led_data, cdev); int ret; unsigned long enable; enum ns2_led_modes mode; ret = kstrtoul(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 led_classdev *led_cdev = dev_get_drvdata(dev); struct ns2_led_data *led_dat = container_of(led_cdev, struct ns2_led_data, cdev); return sprintf(buf, "%d\n", led_dat->sata); } static DEVICE_ATTR(sata, 0644, ns2_led_sata_show, ns2_led_sata_store); static int 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 = devm_gpio_request_one(&pdev->dev, template->cmd, gpio_get_value(template->cmd) ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW, template->name); if (ret) { dev_err(&pdev->dev, "%s: failed to setup command GPIO\n", template->name); return ret; } ret = devm_gpio_request_one(&pdev->dev, template->slow, gpio_get_value(template->slow) ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW, template->name); if (ret) { dev_err(&pdev->dev, "%s: failed to setup slow GPIO\n", template->name); return ret; } 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) return ret; /* 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) return ret; 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); return ret; } static void 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); } #ifdef CONFIG_OF_GPIO /* * Translate OpenFirmware node properties into platform_data. */ static int ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata) { struct device_node *np = dev->of_node; struct device_node *child; struct ns2_led *leds; int num_leds = 0; int i = 0; num_leds = of_get_child_count(np); if (!num_leds) return -ENODEV; leds = devm_kzalloc(dev, num_leds * sizeof(struct ns2_led), GFP_KERNEL); if (!leds) return -ENOMEM; for_each_child_of_node(np, child) { const char *string; int ret; ret = of_get_named_gpio(child, "cmd-gpio", 0); if (ret < 0) return ret; leds[i].cmd = ret; ret = of_get_named_gpio(child, "slow-gpio", 0); if (ret < 0) return ret; leds[i].slow = ret; ret = of_property_read_string(child, "label", &string); leds[i].name = (ret == 0) ? string : child->name; ret = of_property_read_string(child, "linux,default-trigger", &string); if (ret == 0) leds[i].default_trigger = string; i++; } pdata->leds = leds; pdata->num_leds = num_leds; return 0; } static const struct of_device_id of_ns2_leds_match[] = { { .compatible = "lacie,ns2-leds", }, {}, }; #endif /* CONFIG_OF_GPIO */ struct ns2_led_priv { int num_leds; struct ns2_led_data leds_data[]; }; static inline int sizeof_ns2_led_priv(int num_leds) { return sizeof(struct ns2_led_priv) + (sizeof(struct ns2_led_data) * num_leds); } static int ns2_led_probe(struct platform_device *pdev) { struct ns2_led_platform_data *pdata = dev_get_platdata(&pdev->dev); struct ns2_led_priv *priv; int i; int ret; #ifdef CONFIG_OF_GPIO if (!pdata) { pdata = devm_kzalloc(&pdev->dev, sizeof(struct ns2_led_platform_data), GFP_KERNEL); if (!pdata) return -ENOMEM; ret = ns2_leds_get_of_pdata(&pdev->dev, pdata); if (ret) return ret; } #else if (!pdata) return -EINVAL; #endif /* CONFIG_OF_GPIO */ priv = devm_kzalloc(&pdev->dev, sizeof_ns2_led_priv(pdata->num_leds), GFP_KERNEL); if (!priv) return -ENOMEM; priv->num_leds = pdata->num_leds; for (i = 0; i < priv->num_leds; i++) { ret = create_ns2_led(pdev, &priv->leds_data[i], &pdata->leds[i]); if (ret < 0) { for (i = i - 1; i >= 0; i--) delete_ns2_led(&priv->leds_data[i]); return ret; } } platform_set_drvdata(pdev, priv); return 0; } static int ns2_led_remove(struct platform_device *pdev) { int i; struct ns2_led_priv *priv; priv = platform_get_drvdata(pdev); for (i = 0; i < priv->num_leds; i++) delete_ns2_led(&priv->leds_data[i]); return 0; } static struct platform_driver ns2_led_driver = { .probe = ns2_led_probe, .remove = ns2_led_remove, .driver = { .name = "leds-ns2", .owner = THIS_MODULE, .of_match_table = of_match_ptr(of_ns2_leds_match), }, }; module_platform_driver(ns2_led_driver); MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>"); MODULE_DESCRIPTION("Network Space v2 LED driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:leds-ns2");