diff options
author | Simon Guinot <sguinot@lacie.com> | 2010-10-07 16:38:49 +0200 |
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committer | Nicolas Pitre <nico@fluxnic.net> | 2010-10-07 14:02:12 -0400 |
commit | 2446783250fc12ba9bc39771e04988692742ed90 (patch) | |
tree | e4db7f8444d2726e7df8d30784e8f4e3fc32f0f4 /drivers/leds/leds-netxbig.c | |
parent | e5971bbc1caf0ccbab3fea74fe37abb649d1c7cf (diff) | |
download | kernel_samsung_tuna-2446783250fc12ba9bc39771e04988692742ed90.zip kernel_samsung_tuna-2446783250fc12ba9bc39771e04988692742ed90.tar.gz kernel_samsung_tuna-2446783250fc12ba9bc39771e04988692742ed90.tar.bz2 |
leds: add LED driver for Big Network series LEDs
This patch add a LED class driver for LEDs found on the LaCie 2Big and
5Big Network v2 boards. The LEDs are wired to a CPLD and are controlled
through a GPIO extension bus.
Signed-off-by: Simon Guinot <sguinot@lacie.com>
Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Diffstat (limited to 'drivers/leds/leds-netxbig.c')
-rw-r--r-- | drivers/leds/leds-netxbig.c | 449 |
1 files changed, 449 insertions, 0 deletions
diff --git a/drivers/leds/leds-netxbig.c b/drivers/leds/leds-netxbig.c new file mode 100644 index 0000000..f2e51c1 --- /dev/null +++ b/drivers/leds/leds-netxbig.c @@ -0,0 +1,449 @@ +/* + * 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/init.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 <mach/leds-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 __devinit 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(gpio_ext->addr[i], "GPIO extension addr"); + if (err) + goto err_free_addr; + err = gpio_direction_output(gpio_ext->addr[i], 0); + if (err) { + gpio_free(gpio_ext->addr[i]); + goto err_free_addr; + } + } + /* Configure data GPIOs. */ + for (i = 0; i < gpio_ext->num_data; i++) { + err = gpio_request(gpio_ext->data[i], "GPIO extension data"); + if (err) + goto err_free_data; + err = gpio_direction_output(gpio_ext->data[i], 0); + if (err) { + gpio_free(gpio_ext->data[i]); + goto err_free_data; + } + } + /* Configure "enable select" GPIO. */ + err = gpio_request(gpio_ext->enable, "GPIO extension enable"); + if (err) + goto err_free_data; + err = gpio_direction_output(gpio_ext->enable, 0); + if (err) { + gpio_free(gpio_ext->enable); + 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 __devexit 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 = strict_strtoul(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 void __devexit delete_netxbig_led(struct netxbig_led_data *led_dat) +{ + if (led_dat->mode_val[NETXBIG_LED_SATA] != NETXBIG_LED_INVALID_MODE) + device_remove_file(led_dat->cdev.dev, &dev_attr_sata); + led_classdev_unregister(&led_dat->cdev); +} + +static int __devinit +create_netxbig_led(struct platform_device *pdev, + struct netxbig_led_data *led_dat, + const struct netxbig_led *template) +{ + struct netxbig_led_platform_data *pdata = pdev->dev.platform_data; + int ret; + + 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; + + ret = led_classdev_register(&pdev->dev, &led_dat->cdev); + if (ret < 0) + return ret; + + /* + * 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) { + ret = device_create_file(led_dat->cdev.dev, &dev_attr_sata); + if (ret) + led_classdev_unregister(&led_dat->cdev); + } + + return ret; +} + +static int __devinit netxbig_led_probe(struct platform_device *pdev) +{ + struct netxbig_led_platform_data *pdata = pdev->dev.platform_data; + struct netxbig_led_data *leds_data; + int i; + int ret; + + if (!pdata) + return -EINVAL; + + leds_data = kzalloc(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) + goto err_free_data; + + 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); +err_free_data: + kfree(leds_data); + + return ret; +} + +static int __devexit netxbig_led_remove(struct platform_device *pdev) +{ + struct netxbig_led_platform_data *pdata = pdev->dev.platform_data; + 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); + kfree(leds_data); + + return 0; +} + +static struct platform_driver netxbig_led_driver = { + .probe = netxbig_led_probe, + .remove = __devexit_p(netxbig_led_remove), + .driver = { + .name = "leds-netxbig", + .owner = THIS_MODULE, + }, +}; +MODULE_ALIAS("platform:leds-netxbig"); + +static int __init netxbig_led_init(void) +{ + return platform_driver_register(&netxbig_led_driver); +} + +static void __exit netxbig_led_exit(void) +{ + platform_driver_unregister(&netxbig_led_driver); +} + +module_init(netxbig_led_init); +module_exit(netxbig_led_exit); + +MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>"); +MODULE_DESCRIPTION("LED driver for LaCie xBig Network boards"); +MODULE_LICENSE("GPL"); |