// SPDX-License-Identifier: GPL-2.0-or-later /* * leds-netxbig.c - Driver for the 2Big and 5Big Network series LEDs * * Copyright (C) 2010 LaCie * * Author: Simon Guinot <sguinot@lacie.com> */ #include <linux/module.h> #include <linux/irq.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/platform_device.h> #include <linux/gpio/consumer.h> #include <linux/leds.h> #include <linux/of.h> #include <linux/of_platform.h> struct netxbig_gpio_ext { struct gpio_desc **addr; int num_addr; struct gpio_desc **data; int num_data; struct gpio_desc *enable; }; enum netxbig_led_mode { NETXBIG_LED_OFF, NETXBIG_LED_ON, NETXBIG_LED_SATA, NETXBIG_LED_TIMER1, NETXBIG_LED_TIMER2, NETXBIG_LED_MODE_NUM, }; #define NETXBIG_LED_INVALID_MODE NETXBIG_LED_MODE_NUM struct netxbig_led_timer { unsigned long delay_on; unsigned long delay_off; enum netxbig_led_mode mode; }; struct netxbig_led { const char *name; const char *default_trigger; int mode_addr; int *mode_val; int bright_addr; int bright_max; }; struct netxbig_led_platform_data { struct netxbig_gpio_ext *gpio_ext; struct netxbig_led_timer *timer; int num_timer; struct netxbig_led *leds; int num_leds; }; /* * 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++) gpiod_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++) gpiod_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. */ gpiod_set_value(gpio_ext->enable, 0); gpiod_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); } /* * 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; 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; 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) gpio_ext_set_value(led_dat->gpio_ext, led_dat->bright_addr, value); 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 int create_netxbig_led(struct platform_device *pdev, struct netxbig_led_platform_data *pdata, struct netxbig_led_data *led_dat, const struct netxbig_led *template) { 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.max_brightness = template->bright_max; 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->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 devm_led_classdev_register(&pdev->dev, &led_dat->cdev); } /** * netxbig_gpio_ext_remove() - Clean up GPIO extension data * @data: managed resource data to clean up * * Since we pick GPIO descriptors from another device than the device our * driver is probing to, we need to register a specific callback to free * these up using managed resources. */ static void netxbig_gpio_ext_remove(void *data) { struct netxbig_gpio_ext *gpio_ext = data; int i; for (i = 0; i < gpio_ext->num_addr; i++) gpiod_put(gpio_ext->addr[i]); for (i = 0; i < gpio_ext->num_data; i++) gpiod_put(gpio_ext->data[i]); gpiod_put(gpio_ext->enable); } /** * netxbig_gpio_ext_get() - Obtain GPIO extension device data * @dev: main LED device * @gpio_ext_dev: the GPIO extension device * @gpio_ext: the data structure holding the GPIO extension data * * This function walks the subdevice that only contain GPIO line * handles in the device tree and obtains the GPIO descriptors from that * device. */ static int netxbig_gpio_ext_get(struct device *dev, struct device *gpio_ext_dev, struct netxbig_gpio_ext *gpio_ext) { struct gpio_desc **addr, **data; int num_addr, num_data; struct gpio_desc *gpiod; int ret; int i; ret = gpiod_count(gpio_ext_dev, "addr"); if (ret < 0) { dev_err(dev, "Failed to count GPIOs in DT property addr-gpios\n"); return ret; } num_addr = ret; addr = devm_kcalloc(dev, num_addr, sizeof(*addr), GFP_KERNEL); if (!addr) return -ENOMEM; /* * We cannot use devm_ managed resources with these GPIO descriptors * since they are associated with the "GPIO extension device" which * does not probe any driver. The device tree parser will however * populate a platform device for it so we can anyway obtain the * GPIO descriptors from the device. */ for (i = 0; i < num_addr; i++) { gpiod = gpiod_get_index(gpio_ext_dev, "addr", i, GPIOD_OUT_LOW); if (IS_ERR(gpiod)) return PTR_ERR(gpiod); gpiod_set_consumer_name(gpiod, "GPIO extension addr"); addr[i] = gpiod; } gpio_ext->addr = addr; gpio_ext->num_addr = num_addr; ret = gpiod_count(gpio_ext_dev, "data"); if (ret < 0) { dev_err(dev, "Failed to count GPIOs in DT property data-gpios\n"); return ret; } num_data = ret; data = devm_kcalloc(dev, num_data, sizeof(*data), GFP_KERNEL); if (!data) return -ENOMEM; for (i = 0; i < num_data; i++) { gpiod = gpiod_get_index(gpio_ext_dev, "data", i, GPIOD_OUT_LOW); if (IS_ERR(gpiod)) return PTR_ERR(gpiod); gpiod_set_consumer_name(gpiod, "GPIO extension data"); data[i] = gpiod; } gpio_ext->data = data; gpio_ext->num_data = num_data; gpiod = gpiod_get(gpio_ext_dev, "enable", GPIOD_OUT_LOW); if (IS_ERR(gpiod)) { dev_err(dev, "Failed to get GPIO from DT property enable-gpio\n"); return PTR_ERR(gpiod); } gpiod_set_consumer_name(gpiod, "GPIO extension enable"); gpio_ext->enable = gpiod; return devm_add_action_or_reset(dev, netxbig_gpio_ext_remove, gpio_ext); } static int netxbig_leds_get_of_pdata(struct device *dev, struct netxbig_led_platform_data *pdata) { struct device_node *np = dev->of_node; struct device_node *gpio_ext_np; struct platform_device *gpio_ext_pdev; struct device *gpio_ext_dev; struct device_node *child; struct netxbig_gpio_ext *gpio_ext; struct netxbig_led_timer *timers; struct netxbig_led *leds, *led; int num_timers; int num_leds = 0; int ret; int i; /* GPIO extension */ gpio_ext_np = of_parse_phandle(np, "gpio-ext", 0); if (!gpio_ext_np) { dev_err(dev, "Failed to get DT handle gpio-ext\n"); return -EINVAL; } gpio_ext_pdev = of_find_device_by_node(gpio_ext_np); if (!gpio_ext_pdev) { dev_err(dev, "Failed to find platform device for gpio-ext\n"); return -ENODEV; } gpio_ext_dev = &gpio_ext_pdev->dev; gpio_ext = devm_kzalloc(dev, sizeof(*gpio_ext), GFP_KERNEL); if (!gpio_ext) { of_node_put(gpio_ext_np); return -ENOMEM; } ret = netxbig_gpio_ext_get(dev, gpio_ext_dev, gpio_ext); of_node_put(gpio_ext_np); if (ret) return ret; pdata->gpio_ext = gpio_ext; /* Timers (optional) */ ret = of_property_count_u32_elems(np, "timers"); if (ret > 0) { if (ret % 3) return -EINVAL; num_timers = ret / 3; timers = devm_kcalloc(dev, num_timers, sizeof(*timers), GFP_KERNEL); if (!timers) return -ENOMEM; for (i = 0; i < num_timers; i++) { u32 tmp; of_property_read_u32_index(np, "timers", 3 * i, &timers[i].mode); if (timers[i].mode >= NETXBIG_LED_MODE_NUM) return -EINVAL; of_property_read_u32_index(np, "timers", 3 * i + 1, &tmp); timers[i].delay_on = tmp; of_property_read_u32_index(np, "timers", 3 * i + 2, &tmp); timers[i].delay_off = tmp; } pdata->timer = timers; pdata->num_timer = num_timers; } /* LEDs */ num_leds = of_get_child_count(np); if (!num_leds) { dev_err(dev, "No LED subnodes found in DT\n"); return -ENODEV; } leds = devm_kcalloc(dev, num_leds, sizeof(*leds), GFP_KERNEL); if (!leds) return -ENOMEM; led = leds; for_each_child_of_node(np, child) { const char *string; int *mode_val; int num_modes; ret = of_property_read_u32(child, "mode-addr", &led->mode_addr); if (ret) goto err_node_put; ret = of_property_read_u32(child, "bright-addr", &led->bright_addr); if (ret) goto err_node_put; ret = of_property_read_u32(child, "max-brightness", &led->bright_max); if (ret) goto err_node_put; mode_val = devm_kcalloc(dev, NETXBIG_LED_MODE_NUM, sizeof(*mode_val), GFP_KERNEL); if (!mode_val) { ret = -ENOMEM; goto err_node_put; } for (i = 0; i < NETXBIG_LED_MODE_NUM; i++) mode_val[i] = NETXBIG_LED_INVALID_MODE; ret = of_property_count_u32_elems(child, "mode-val"); if (ret < 0 || ret % 2) { ret = -EINVAL; goto err_node_put; } num_modes = ret / 2; if (num_modes > NETXBIG_LED_MODE_NUM) { ret = -EINVAL; goto err_node_put; } for (i = 0; i < num_modes; i++) { int mode; int val; of_property_read_u32_index(child, "mode-val", 2 * i, &mode); of_property_read_u32_index(child, "mode-val", 2 * i + 1, &val); if (mode >= NETXBIG_LED_MODE_NUM) { ret = -EINVAL; goto err_node_put; } mode_val[mode] = val; } led->mode_val = mode_val; if (!of_property_read_string(child, "label", &string)) led->name = string; else led->name = child->name; if (!of_property_read_string(child, "linux,default-trigger", &string)) led->default_trigger = string; led++; } pdata->leds = leds; pdata->num_leds = num_leds; return 0; err_node_put: of_node_put(child); return ret; } static const struct of_device_id of_netxbig_leds_match[] = { { .compatible = "lacie,netxbig-leds", }, {}, }; MODULE_DEVICE_TABLE(of, of_netxbig_leds_match); static int netxbig_led_probe(struct platform_device *pdev) { struct netxbig_led_platform_data *pdata; struct netxbig_led_data *leds_data; int i; int ret; pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); if (!pdata) return -ENOMEM; ret = netxbig_leds_get_of_pdata(&pdev->dev, pdata); if (ret) return ret; leds_data = devm_kcalloc(&pdev->dev, pdata->num_leds, sizeof(*leds_data), GFP_KERNEL); if (!leds_data) return -ENOMEM; for (i = 0; i < pdata->num_leds; i++) { ret = create_netxbig_led(pdev, pdata, &leds_data[i], &pdata->leds[i]); if (ret < 0) return ret; } return 0; } static struct platform_driver netxbig_led_driver = { .probe = netxbig_led_probe, .driver = { .name = "leds-netxbig", .of_match_table = of_netxbig_leds_match, }, }; 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");