/* * leds-netxbig.c - Driver for the 2Big and 5Big Network series LEDs * * Copyright (C) 2010 LaCie * * Author: Simon Guinot <sguinot@lacie.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/module.h> #include <linux/irq.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/platform_device.h> #include <linux/gpio.h> #include <linux/leds.h> #include <linux/platform_data/leds-kirkwood-netxbig.h> /* * GPIO extension bus. */ static DEFINE_SPINLOCK(gpio_ext_lock); static void gpio_ext_set_addr(struct netxbig_gpio_ext *gpio_ext, int addr) { int pin; for (pin = 0; pin < gpio_ext->num_addr; pin++) gpio_set_value(gpio_ext->addr[pin], (addr >> pin) & 1); } static void gpio_ext_set_data(struct netxbig_gpio_ext *gpio_ext, int data) { int pin; for (pin = 0; pin < gpio_ext->num_data; pin++) gpio_set_value(gpio_ext->data[pin], (data >> pin) & 1); } static void gpio_ext_enable_select(struct netxbig_gpio_ext *gpio_ext) { /* Enable select is done on the raising edge. */ gpio_set_value(gpio_ext->enable, 0); gpio_set_value(gpio_ext->enable, 1); } static void gpio_ext_set_value(struct netxbig_gpio_ext *gpio_ext, int addr, int value) { unsigned long flags; spin_lock_irqsave(&gpio_ext_lock, flags); gpio_ext_set_addr(gpio_ext, addr); gpio_ext_set_data(gpio_ext, value); gpio_ext_enable_select(gpio_ext); spin_unlock_irqrestore(&gpio_ext_lock, flags); } static int gpio_ext_init(struct netxbig_gpio_ext *gpio_ext) { int err; int i; if (unlikely(!gpio_ext)) return -EINVAL; /* Configure address GPIOs. */ for (i = 0; i < gpio_ext->num_addr; i++) { err = gpio_request_one(gpio_ext->addr[i], GPIOF_OUT_INIT_LOW, "GPIO extension addr"); if (err) goto err_free_addr; } /* Configure data GPIOs. */ for (i = 0; i < gpio_ext->num_data; i++) { err = gpio_request_one(gpio_ext->data[i], GPIOF_OUT_INIT_LOW, "GPIO extension data"); if (err) goto err_free_data; } /* Configure "enable select" GPIO. */ err = gpio_request_one(gpio_ext->enable, GPIOF_OUT_INIT_LOW, "GPIO extension enable"); if (err) goto err_free_data; return 0; err_free_data: for (i = i - 1; i >= 0; i--) gpio_free(gpio_ext->data[i]); i = gpio_ext->num_addr; err_free_addr: for (i = i - 1; i >= 0; i--) gpio_free(gpio_ext->addr[i]); return err; } static void gpio_ext_free(struct netxbig_gpio_ext *gpio_ext) { int i; gpio_free(gpio_ext->enable); for (i = gpio_ext->num_addr - 1; i >= 0; i--) gpio_free(gpio_ext->addr[i]); for (i = gpio_ext->num_data - 1; i >= 0; i--) gpio_free(gpio_ext->data[i]); } /* * Class LED driver. */ struct netxbig_led_data { struct netxbig_gpio_ext *gpio_ext; struct led_classdev cdev; int mode_addr; int *mode_val; int bright_addr; int bright_max; struct netxbig_led_timer *timer; int num_timer; enum netxbig_led_mode mode; int sata; spinlock_t lock; }; static int netxbig_led_get_timer_mode(enum netxbig_led_mode *mode, unsigned long delay_on, unsigned long delay_off, struct netxbig_led_timer *timer, int num_timer) { int i; for (i = 0; i < num_timer; i++) { if (timer[i].delay_on == delay_on && timer[i].delay_off == delay_off) { *mode = timer[i].mode; return 0; } } return -EINVAL; } static int netxbig_led_blink_set(struct led_classdev *led_cdev, unsigned long *delay_on, unsigned long *delay_off) { struct netxbig_led_data *led_dat = container_of(led_cdev, struct netxbig_led_data, cdev); enum netxbig_led_mode mode; int mode_val; int ret; /* Look for a LED mode with the requested timer frequency. */ ret = netxbig_led_get_timer_mode(&mode, *delay_on, *delay_off, led_dat->timer, led_dat->num_timer); if (ret < 0) return ret; mode_val = led_dat->mode_val[mode]; if (mode_val == NETXBIG_LED_INVALID_MODE) return -EINVAL; spin_lock_irq(&led_dat->lock); gpio_ext_set_value(led_dat->gpio_ext, led_dat->mode_addr, mode_val); led_dat->mode = mode; spin_unlock_irq(&led_dat->lock); return 0; } static void netxbig_led_set(struct led_classdev *led_cdev, enum led_brightness value) { struct netxbig_led_data *led_dat = container_of(led_cdev, struct netxbig_led_data, cdev); enum netxbig_led_mode mode; int mode_val, bright_val; int set_brightness = 1; unsigned long flags; spin_lock_irqsave(&led_dat->lock, flags); if (value == LED_OFF) { mode = NETXBIG_LED_OFF; set_brightness = 0; } else { if (led_dat->sata) mode = NETXBIG_LED_SATA; else if (led_dat->mode == NETXBIG_LED_OFF) mode = NETXBIG_LED_ON; else /* Keep 'timer' mode. */ mode = led_dat->mode; } mode_val = led_dat->mode_val[mode]; gpio_ext_set_value(led_dat->gpio_ext, led_dat->mode_addr, mode_val); led_dat->mode = mode; /* * Note that the brightness register is shared between all the * SATA LEDs. So, change the brightness setting for a single * SATA LED will affect all the others. */ if (set_brightness) { bright_val = DIV_ROUND_UP(value * led_dat->bright_max, LED_FULL); gpio_ext_set_value(led_dat->gpio_ext, led_dat->bright_addr, bright_val); } spin_unlock_irqrestore(&led_dat->lock, flags); } static ssize_t netxbig_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 netxbig_led_data *led_dat = container_of(led_cdev, struct netxbig_led_data, cdev); unsigned long enable; enum netxbig_led_mode mode; int mode_val; int ret; ret = kstrtoul(buff, 10, &enable); if (ret < 0) return ret; enable = !!enable; spin_lock_irq(&led_dat->lock); if (led_dat->sata == enable) { ret = count; goto exit_unlock; } if (led_dat->mode != NETXBIG_LED_ON && led_dat->mode != NETXBIG_LED_SATA) mode = led_dat->mode; /* Keep modes 'off' and 'timer'. */ else if (enable) mode = NETXBIG_LED_SATA; else mode = NETXBIG_LED_ON; mode_val = led_dat->mode_val[mode]; if (mode_val == NETXBIG_LED_INVALID_MODE) { ret = -EINVAL; goto exit_unlock; } gpio_ext_set_value(led_dat->gpio_ext, led_dat->mode_addr, mode_val); led_dat->mode = mode; led_dat->sata = enable; ret = count; exit_unlock: spin_unlock_irq(&led_dat->lock); return ret; } static ssize_t netxbig_led_sata_show(struct device *dev, struct device_attribute *attr, char *buf) { struct led_classdev *led_cdev = dev_get_drvdata(dev); struct netxbig_led_data *led_dat = container_of(led_cdev, struct netxbig_led_data, cdev); return sprintf(buf, "%d\n", led_dat->sata); } static DEVICE_ATTR(sata, 0644, netxbig_led_sata_show, netxbig_led_sata_store); static struct attribute *netxbig_led_attrs[] = { &dev_attr_sata.attr, NULL }; ATTRIBUTE_GROUPS(netxbig_led); static void delete_netxbig_led(struct netxbig_led_data *led_dat) { led_classdev_unregister(&led_dat->cdev); } static int create_netxbig_led(struct platform_device *pdev, struct netxbig_led_data *led_dat, const struct netxbig_led *template) { struct netxbig_led_platform_data *pdata = dev_get_platdata(&pdev->dev); spin_lock_init(&led_dat->lock); led_dat->gpio_ext = pdata->gpio_ext; led_dat->cdev.name = template->name; led_dat->cdev.default_trigger = template->default_trigger; led_dat->cdev.blink_set = netxbig_led_blink_set; led_dat->cdev.brightness_set = netxbig_led_set; /* * Because the GPIO extension bus don't allow to read registers * value, there is no way to probe the LED initial state. * So, the initial sysfs LED value for the "brightness" and "sata" * attributes are inconsistent. * * Note that the initial LED state can't be reconfigured. * The reason is that the LED behaviour must stay uniform during * the whole boot process (bootloader+linux). */ led_dat->sata = 0; led_dat->cdev.brightness = LED_OFF; led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME; led_dat->mode_addr = template->mode_addr; led_dat->mode_val = template->mode_val; led_dat->bright_addr = template->bright_addr; led_dat->bright_max = (1 << pdata->gpio_ext->num_data) - 1; led_dat->timer = pdata->timer; led_dat->num_timer = pdata->num_timer; /* * If available, expose the SATA activity blink capability through * a "sata" sysfs attribute. */ if (led_dat->mode_val[NETXBIG_LED_SATA] != NETXBIG_LED_INVALID_MODE) led_dat->cdev.groups = netxbig_led_groups; return led_classdev_register(&pdev->dev, &led_dat->cdev); } static int netxbig_led_probe(struct platform_device *pdev) { struct netxbig_led_platform_data *pdata = dev_get_platdata(&pdev->dev); struct netxbig_led_data *leds_data; int i; int ret; if (!pdata) return -EINVAL; leds_data = devm_kzalloc(&pdev->dev, sizeof(struct netxbig_led_data) * pdata->num_leds, GFP_KERNEL); if (!leds_data) return -ENOMEM; ret = gpio_ext_init(pdata->gpio_ext); if (ret < 0) return ret; for (i = 0; i < pdata->num_leds; i++) { ret = create_netxbig_led(pdev, &leds_data[i], &pdata->leds[i]); if (ret < 0) goto err_free_leds; } platform_set_drvdata(pdev, leds_data); return 0; err_free_leds: for (i = i - 1; i >= 0; i--) delete_netxbig_led(&leds_data[i]); gpio_ext_free(pdata->gpio_ext); return ret; } static int netxbig_led_remove(struct platform_device *pdev) { struct netxbig_led_platform_data *pdata = dev_get_platdata(&pdev->dev); struct netxbig_led_data *leds_data; int i; leds_data = platform_get_drvdata(pdev); for (i = 0; i < pdata->num_leds; i++) delete_netxbig_led(&leds_data[i]); gpio_ext_free(pdata->gpio_ext); return 0; } static struct platform_driver netxbig_led_driver = { .probe = netxbig_led_probe, .remove = netxbig_led_remove, .driver = { .name = "leds-netxbig", }, }; module_platform_driver(netxbig_led_driver); MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>"); MODULE_DESCRIPTION("LED driver for LaCie xBig Network boards"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:leds-netxbig");