linux/drivers/leds/leds-netxbig.c

423 lines
11 KiB
C

/*
* 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 <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 void 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
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 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 = 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 = 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);
return 0;
}
static struct platform_driver netxbig_led_driver = {
.probe = netxbig_led_probe,
.remove = netxbig_led_remove,
.driver = {
.name = "leds-netxbig",
.owner = THIS_MODULE,
},
};
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");