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path: root/drivers/leds/trigger/ledtrig-gpio.c
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Diffstat (limited to 'drivers/leds/trigger/ledtrig-gpio.c')
-rw-r--r--drivers/leds/trigger/ledtrig-gpio.c157
1 files changed, 48 insertions, 109 deletions
diff --git a/drivers/leds/trigger/ledtrig-gpio.c b/drivers/leds/trigger/ledtrig-gpio.c
index ed0db8ed825f..7f6a2352b0ac 100644
--- a/drivers/leds/trigger/ledtrig-gpio.c
+++ b/drivers/leds/trigger/ledtrig-gpio.c
@@ -1,17 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* ledtrig-gio.c - LED Trigger Based on GPIO events
*
* Copyright 2009 Felipe Balbi <me@felipebalbi.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
+ * Copyright 2023 Linus Walleij <linus.walleij@linaro.org>
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
#include <linux/interrupt.h>
#include <linux/leds.h>
#include <linux/slab.h>
@@ -19,10 +17,8 @@
struct gpio_trig_data {
struct led_classdev *led;
-
unsigned desired_brightness; /* desired brightness when led is on */
- unsigned inverted; /* true when gpio is inverted */
- unsigned gpio; /* gpio that triggers the leds */
+ struct gpio_desc *gpiod; /* gpio that triggers the led */
};
static irqreturn_t gpio_trig_irq(int irq, void *_led)
@@ -31,10 +27,7 @@ static irqreturn_t gpio_trig_irq(int irq, void *_led)
struct gpio_trig_data *gpio_data = led_get_trigger_data(led);
int tmp;
- tmp = gpio_get_value_cansleep(gpio_data->gpio);
- if (gpio_data->inverted)
- tmp = !tmp;
-
+ tmp = gpiod_get_value_cansleep(gpio_data->gpiod);
if (tmp) {
if (gpio_data->desired_brightness)
led_set_brightness_nosleep(gpio_data->led,
@@ -48,120 +41,33 @@ static irqreturn_t gpio_trig_irq(int irq, void *_led)
return IRQ_HANDLED;
}
-static ssize_t gpio_trig_brightness_show(struct device *dev,
+static ssize_t desired_brightness_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct gpio_trig_data *gpio_data = led_trigger_get_drvdata(dev);
- return sprintf(buf, "%u\n", gpio_data->desired_brightness);
+ return sysfs_emit(buf, "%u\n", gpio_data->desired_brightness);
}
-static ssize_t gpio_trig_brightness_store(struct device *dev,
+static ssize_t desired_brightness_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t n)
{
struct gpio_trig_data *gpio_data = led_trigger_get_drvdata(dev);
- unsigned desired_brightness;
+ u8 desired_brightness;
int ret;
- ret = sscanf(buf, "%u", &desired_brightness);
- if (ret < 1 || desired_brightness > 255) {
- dev_err(dev, "invalid value\n");
- return -EINVAL;
- }
-
- gpio_data->desired_brightness = desired_brightness;
-
- return n;
-}
-static DEVICE_ATTR(desired_brightness, 0644, gpio_trig_brightness_show,
- gpio_trig_brightness_store);
-
-static ssize_t gpio_trig_inverted_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct gpio_trig_data *gpio_data = led_trigger_get_drvdata(dev);
-
- return sprintf(buf, "%u\n", gpio_data->inverted);
-}
-
-static ssize_t gpio_trig_inverted_store(struct device *dev,
- struct device_attribute *attr, const char *buf, size_t n)
-{
- struct led_classdev *led = led_trigger_get_led(dev);
- struct gpio_trig_data *gpio_data = led_trigger_get_drvdata(dev);
- unsigned long inverted;
- int ret;
-
- ret = kstrtoul(buf, 10, &inverted);
- if (ret < 0)
+ ret = kstrtou8(buf, 10, &desired_brightness);
+ if (ret)
return ret;
- if (inverted > 1)
- return -EINVAL;
-
- gpio_data->inverted = inverted;
-
- /* After inverting, we need to update the LED. */
- gpio_trig_irq(0, led);
+ gpio_data->desired_brightness = desired_brightness;
return n;
}
-static DEVICE_ATTR(inverted, 0644, gpio_trig_inverted_show,
- gpio_trig_inverted_store);
-
-static ssize_t gpio_trig_gpio_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct gpio_trig_data *gpio_data = led_trigger_get_drvdata(dev);
-
- return sprintf(buf, "%u\n", gpio_data->gpio);
-}
-
-static ssize_t gpio_trig_gpio_store(struct device *dev,
- struct device_attribute *attr, const char *buf, size_t n)
-{
- struct led_classdev *led = led_trigger_get_led(dev);
- struct gpio_trig_data *gpio_data = led_trigger_get_drvdata(dev);
- unsigned gpio;
- int ret;
-
- ret = sscanf(buf, "%u", &gpio);
- if (ret < 1) {
- dev_err(dev, "couldn't read gpio number\n");
- return -EINVAL;
- }
-
- if (gpio_data->gpio == gpio)
- return n;
-
- if (!gpio) {
- if (gpio_data->gpio != 0)
- free_irq(gpio_to_irq(gpio_data->gpio), led);
- gpio_data->gpio = 0;
- return n;
- }
-
- ret = request_threaded_irq(gpio_to_irq(gpio), NULL, gpio_trig_irq,
- IRQF_ONESHOT | IRQF_SHARED | IRQF_TRIGGER_RISING
- | IRQF_TRIGGER_FALLING, "ledtrig-gpio", led);
- if (ret) {
- dev_err(dev, "request_irq failed with error %d\n", ret);
- } else {
- if (gpio_data->gpio != 0)
- free_irq(gpio_to_irq(gpio_data->gpio), led);
- gpio_data->gpio = gpio;
- /* After changing the GPIO, we need to update the LED. */
- gpio_trig_irq(0, led);
- }
-
- return ret ? ret : n;
-}
-static DEVICE_ATTR(gpio, 0644, gpio_trig_gpio_show, gpio_trig_gpio_store);
+static DEVICE_ATTR_RW(desired_brightness);
static struct attribute *gpio_trig_attrs[] = {
&dev_attr_desired_brightness.attr,
- &dev_attr_inverted.attr,
- &dev_attr_gpio.attr,
NULL
};
ATTRIBUTE_GROUPS(gpio_trig);
@@ -169,14 +75,47 @@ ATTRIBUTE_GROUPS(gpio_trig);
static int gpio_trig_activate(struct led_classdev *led)
{
struct gpio_trig_data *gpio_data;
+ struct device *dev = led->dev;
+ int ret;
gpio_data = kzalloc(sizeof(*gpio_data), GFP_KERNEL);
if (!gpio_data)
return -ENOMEM;
+ /*
+ * The generic property "trigger-sources" is followed,
+ * and we hope that this is a GPIO.
+ */
+ gpio_data->gpiod = gpiod_get_optional(dev, "trigger-sources", GPIOD_IN);
+ if (IS_ERR(gpio_data->gpiod)) {
+ ret = PTR_ERR(gpio_data->gpiod);
+ kfree(gpio_data);
+ return ret;
+ }
+ if (!gpio_data->gpiod) {
+ dev_err(dev, "no valid GPIO for the trigger\n");
+ kfree(gpio_data);
+ return -EINVAL;
+ }
+
+ gpiod_set_consumer_name(gpio_data->gpiod, "led-trigger");
+
gpio_data->led = led;
led_set_trigger_data(led, gpio_data);
+ ret = request_threaded_irq(gpiod_to_irq(gpio_data->gpiod), NULL, gpio_trig_irq,
+ IRQF_ONESHOT | IRQF_SHARED | IRQF_TRIGGER_RISING
+ | IRQF_TRIGGER_FALLING, "ledtrig-gpio", led);
+ if (ret) {
+ dev_err(dev, "request_irq failed with error %d\n", ret);
+ gpiod_put(gpio_data->gpiod);
+ kfree(gpio_data);
+ return ret;
+ }
+
+ /* Finally update the LED to initial status */
+ gpio_trig_irq(0, led);
+
return 0;
}
@@ -184,8 +123,8 @@ static void gpio_trig_deactivate(struct led_classdev *led)
{
struct gpio_trig_data *gpio_data = led_get_trigger_data(led);
- if (gpio_data->gpio != 0)
- free_irq(gpio_to_irq(gpio_data->gpio), led);
+ free_irq(gpiod_to_irq(gpio_data->gpiod), led);
+ gpiod_put(gpio_data->gpiod);
kfree(gpio_data);
}