diff options
Diffstat (limited to 'kernel/drivers/leds/leds-ns2.c')
| -rw-r--r-- | kernel/drivers/leds/leds-ns2.c | 392 |
1 files changed, 392 insertions, 0 deletions
diff --git a/kernel/drivers/leds/leds-ns2.c b/kernel/drivers/leds/leds-ns2.c new file mode 100644 index 000000000..1fd6adbb4 --- /dev/null +++ b/kernel/drivers/leds/leds-ns2.c @@ -0,0 +1,392 @@ +/* + * 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/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 struct attribute *ns2_led_attrs[] = { + &dev_attr_sata.attr, + NULL +}; +ATTRIBUTE_GROUPS(ns2_led); + +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->cdev.groups = ns2_led_groups; + 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; + + return 0; +} + +static void delete_ns2_led(struct ns2_led_data *led_dat) +{ + 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", + .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"); |