linux/drivers/leds/leds-ns2.c
Linus Walleij ccbbb117c1 leds: ns2: Convert to GPIO descriptors
This converts the NS2 LED driver to use GPIO descriptors.
We take care to request the GPIOs "as is" which is what
the current driver goes to lengths to achieve, then we use
GPIOs throughout.

As the nodes for each LED does not have any corresponding
device, we need to use the DT-specific accessors to get these
GPIO descriptors from the device tree.

Cc: Vincent Donnefort <vdonnefort@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Simon Guinot <simon.guinot@sequanux.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-02-26 14:34:48 +01:00

430 lines
9.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* 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>
*/
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/gpio/consumer.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/of.h>
#include "leds.h"
enum ns2_led_modes {
NS_V2_LED_OFF,
NS_V2_LED_ON,
NS_V2_LED_SATA,
};
struct ns2_led_modval {
enum ns2_led_modes mode;
int cmd_level;
int slow_level;
};
struct ns2_led {
const char *name;
const char *default_trigger;
struct gpio_desc *cmd;
struct gpio_desc *slow;
int num_modes;
struct ns2_led_modval *modval;
};
struct ns2_led_platform_data {
int num_leds;
struct ns2_led *leds;
};
/*
* The Network Space v2 dual-GPIO LED is wired to a CPLD. Three different LED
* modes are available: off, on and SATA activity blinking. The LED modes are
* controlled through two GPIOs (command and slow): each combination of values
* for the command/slow GPIOs corresponds to a LED mode.
*/
struct ns2_led_data {
struct led_classdev cdev;
struct gpio_desc *cmd;
struct gpio_desc *slow;
bool can_sleep;
unsigned char sata; /* True when SATA mode active. */
rwlock_t rw_lock; /* Lock GPIOs. */
int num_modes;
struct ns2_led_modval *modval;
};
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;
cmd_level = gpiod_get_value_cansleep(led_dat->cmd);
slow_level = gpiod_get_value_cansleep(led_dat->slow);
for (i = 0; i < led_dat->num_modes; i++) {
if (cmd_level == led_dat->modval[i].cmd_level &&
slow_level == led_dat->modval[i].slow_level) {
*mode = led_dat->modval[i].mode;
ret = 0;
break;
}
}
return ret;
}
static void ns2_led_set_mode(struct ns2_led_data *led_dat,
enum ns2_led_modes mode)
{
int i;
bool found = false;
unsigned long flags;
for (i = 0; i < led_dat->num_modes; i++)
if (mode == led_dat->modval[i].mode) {
found = true;
break;
}
if (!found)
return;
write_lock_irqsave(&led_dat->rw_lock, flags);
if (!led_dat->can_sleep) {
gpiod_set_value(led_dat->cmd,
led_dat->modval[i].cmd_level);
gpiod_set_value(led_dat->slow,
led_dat->modval[i].slow_level);
goto exit_unlock;
}
gpiod_set_value_cansleep(led_dat->cmd, led_dat->modval[i].cmd_level);
gpiod_set_value_cansleep(led_dat->slow, led_dat->modval[i].slow_level);
exit_unlock:
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 int ns2_led_set_blocking(struct led_classdev *led_cdev,
enum led_brightness value)
{
ns2_led_set(led_cdev, value);
return 0;
}
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;
ret = kstrtoul(buff, 10, &enable);
if (ret < 0)
return ret;
enable = !!enable;
if (led_dat->sata == enable)
goto exit;
led_dat->sata = enable;
if (!led_get_brightness(led_cdev))
goto exit;
if (enable)
ns2_led_set_mode(led_dat, NS_V2_LED_SATA);
else
ns2_led_set_mode(led_dat, NS_V2_LED_ON);
exit:
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;
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.flags |= LED_CORE_SUSPENDRESUME;
led_dat->cdev.groups = ns2_led_groups;
led_dat->cmd = template->cmd;
led_dat->slow = template->slow;
led_dat->can_sleep = gpiod_cansleep(led_dat->cmd) |
gpiod_cansleep(led_dat->slow);
if (led_dat->can_sleep)
led_dat->cdev.brightness_set_blocking = ns2_led_set_blocking;
else
led_dat->cdev.brightness_set = ns2_led_set;
led_dat->modval = template->modval;
led_dat->num_modes = template->num_modes;
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 *led, *leds;
int ret, num_leds = 0;
num_leds = of_get_child_count(np);
if (!num_leds)
return -ENODEV;
leds = devm_kcalloc(dev, num_leds, sizeof(struct ns2_led),
GFP_KERNEL);
if (!leds)
return -ENOMEM;
led = leds;
for_each_child_of_node(np, child) {
const char *string;
int i, num_modes;
struct ns2_led_modval *modval;
struct gpio_desc *gd;
ret = of_property_read_string(child, "label", &string);
led->name = (ret == 0) ? string : child->name;
gd = gpiod_get_from_of_node(child, "cmd-gpio", 0,
GPIOD_ASIS, led->name);
if (IS_ERR(gd)) {
ret = PTR_ERR(gd);
goto err_node_put;
}
led->cmd = gd;
gd = gpiod_get_from_of_node(child, "slow-gpio", 0,
GPIOD_ASIS, led->name);
if (IS_ERR(gd)) {
ret = PTR_ERR(gd);
goto err_node_put;
}
led->slow = gd;
ret = of_property_read_string(child, "linux,default-trigger",
&string);
if (ret == 0)
led->default_trigger = string;
ret = of_property_count_u32_elems(child, "modes-map");
if (ret < 0 || ret % 3) {
dev_err(dev,
"Missing or malformed modes-map property\n");
ret = -EINVAL;
goto err_node_put;
}
num_modes = ret / 3;
modval = devm_kcalloc(dev,
num_modes,
sizeof(struct ns2_led_modval),
GFP_KERNEL);
if (!modval) {
ret = -ENOMEM;
goto err_node_put;
}
for (i = 0; i < num_modes; i++) {
of_property_read_u32_index(child,
"modes-map", 3 * i,
(u32 *) &modval[i].mode);
of_property_read_u32_index(child,
"modes-map", 3 * i + 1,
(u32 *) &modval[i].cmd_level);
of_property_read_u32_index(child,
"modes-map", 3 * i + 2,
(u32 *) &modval[i].slow_level);
}
led->num_modes = num_modes;
led->modval = modval;
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_ns2_leds_match[] = {
{ .compatible = "lacie,ns2-leds", },
{},
};
MODULE_DEVICE_TABLE(of, of_ns2_leds_match);
#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");