// 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 <[email protected]>
*/
#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 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 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_RW(sata);
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(dev);
struct device_node *gpio_ext_np;
struct platform_device *gpio_ext_pdev;
struct device *gpio_ext_dev;
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);
ret = -ENOMEM;
goto put_device;
}
ret = netxbig_gpio_ext_get(dev, gpio_ext_dev, gpio_ext);
of_node_put(gpio_ext_np);
if (ret)
goto put_device;
pdata->gpio_ext = gpio_ext;
/* Timers (optional) */
ret = of_property_count_u32_elems(np, "timers");
if (ret > 0) {
if (ret % 3) {
ret = -EINVAL;
goto put_device;
}
num_timers = ret / 3;
timers = devm_kcalloc(dev, num_timers, sizeof(*timers),
GFP_KERNEL);
if (!timers) {
ret = -ENOMEM;
goto put_device;
}
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) {
ret = -EINVAL;
goto put_device;
}
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_available_child_count(np);
if (!num_leds) {
dev_err(dev, "No LED subnodes found in DT\n");
ret = -ENODEV;
goto put_device;
}
leds = devm_kcalloc(dev, num_leds, sizeof(*leds), GFP_KERNEL);
if (!leds) {
ret = -ENOMEM;
goto put_device;
}
led = leds;
for_each_available_child_of_node_scoped(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 put_device;
ret = of_property_read_u32(child, "bright-addr",
&led->bright_addr);
if (ret)
goto put_device;
ret = of_property_read_u32(child, "max-brightness",
&led->bright_max);
if (ret)
goto put_device;
mode_val =
devm_kcalloc(dev,
NETXBIG_LED_MODE_NUM, sizeof(*mode_val),
GFP_KERNEL);
if (!mode_val) {
ret = -ENOMEM;
goto put_device;
}
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 put_device;
}
num_modes = ret / 2;
if (num_modes > NETXBIG_LED_MODE_NUM) {
ret = -EINVAL;
goto put_device;
}
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 put_device;
}
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;
put_device:
put_device(gpio_ext_dev);
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 <[email protected]>");
MODULE_DESCRIPTION("LED driver for LaCie xBig Network boards");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:leds-netxbig");
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