1 files changed, 284 insertions, 0 deletions
diff --git a/drivers/leds/leds-ns2.c b/drivers/leds/leds-ns2.c
new file mode 100644
index 000000000..f3010c472
--- /dev/null
+++ b/drivers/leds/leds-ns2.c
@@ -0,0 +1,284 @@
+// 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,
+};
+
+/*
+ * If the size of this structure or types of its members is changed,
+ * the filling of array modval in function ns2_led_register must be changed
+ * accordingly.
+ */
+struct ns2_led_modval {
+	u32			mode;
+	u32			cmd_level;
+	u32			slow_level;
+} __packed;
+
+/*
+ * 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 {
+	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 *led, enum ns2_led_modes *mode)
+{
+	int i;
+	int cmd_level;
+	int slow_level;
+
+	cmd_level = gpiod_get_value_cansleep(led->cmd);
+	slow_level = gpiod_get_value_cansleep(led->slow);
+
+	for (i = 0; i < led->num_modes; i++) {
+		if (cmd_level == led->modval[i].cmd_level &&
+		    slow_level == led->modval[i].slow_level) {
+			*mode = led->modval[i].mode;
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static void ns2_led_set_mode(struct ns2_led *led, enum ns2_led_modes mode)
+{
+	int i;
+	unsigned long flags;
+
+	for (i = 0; i < led->num_modes; i++)
+		if (mode == led->modval[i].mode)
+			break;
+
+	if (i == led->num_modes)
+		return;
+
+	write_lock_irqsave(&led->rw_lock, flags);
+
+	if (!led->can_sleep) {
+		gpiod_set_value(led->cmd, led->modval[i].cmd_level);
+		gpiod_set_value(led->slow, led->modval[i].slow_level);
+		goto exit_unlock;
+	}
+
+	gpiod_set_value_cansleep(led->cmd, led->modval[i].cmd_level);
+	gpiod_set_value_cansleep(led->slow, led->modval[i].slow_level);
+
+exit_unlock:
+	write_unlock_irqrestore(&led->rw_lock, flags);
+}
+
+static void ns2_led_set(struct led_classdev *led_cdev,
+			enum led_brightness value)
+{
+	struct ns2_led *led = container_of(led_cdev, struct ns2_led, cdev);
+	enum ns2_led_modes mode;
+
+	if (value == LED_OFF)
+		mode = NS_V2_LED_OFF;
+	else if (led->sata)
+		mode = NS_V2_LED_SATA;
+	else
+		mode = NS_V2_LED_ON;
+
+	ns2_led_set_mode(led, 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 *led = container_of(led_cdev, struct ns2_led, cdev);
+	int ret;
+	unsigned long enable;
+
+	ret = kstrtoul(buff, 10, &enable);
+	if (ret < 0)
+		return ret;
+
+	enable = !!enable;
+
+	if (led->sata == enable)
+		goto exit;
+
+	led->sata = enable;
+
+	if (!led_get_brightness(led_cdev))
+		goto exit;
+
+	if (enable)
+		ns2_led_set_mode(led, NS_V2_LED_SATA);
+	else
+		ns2_led_set_mode(led, 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 *led = container_of(led_cdev, struct ns2_led, cdev);
+
+	return sprintf(buf, "%d\n", led->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 ns2_led_register(struct device *dev, struct fwnode_handle *node,
+			    struct ns2_led *led)
+{
+	struct led_init_data init_data = {};
+	struct ns2_led_modval *modval;
+	enum ns2_led_modes mode;
+	int nmodes, ret;
+
+	led->cmd = devm_fwnode_gpiod_get_index(dev, node, "cmd", 0, GPIOD_ASIS,
+					       fwnode_get_name(node));
+	if (IS_ERR(led->cmd))
+		return PTR_ERR(led->cmd);
+
+	led->slow = devm_fwnode_gpiod_get_index(dev, node, "slow", 0,
+						GPIOD_ASIS,
+						fwnode_get_name(node));
+	if (IS_ERR(led->slow))
+		return PTR_ERR(led->slow);
+
+	ret = fwnode_property_count_u32(node, "modes-map");
+	if (ret < 0 || ret % 3) {
+		dev_err(dev, "Missing or malformed modes-map for %pfw\n", node);
+		return -EINVAL;
+	}
+
+	nmodes = ret / 3;
+	modval = devm_kcalloc(dev, nmodes, sizeof(*modval), GFP_KERNEL);
+	if (!modval)
+		return -ENOMEM;
+
+	fwnode_property_read_u32_array(node, "modes-map", (void *)modval,
+				       nmodes * 3);
+
+	rwlock_init(&led->rw_lock);
+
+	led->cdev.blink_set = NULL;
+	led->cdev.flags |= LED_CORE_SUSPENDRESUME;
+	led->cdev.groups = ns2_led_groups;
+	led->can_sleep = gpiod_cansleep(led->cmd) || gpiod_cansleep(led->slow);
+	if (led->can_sleep)
+		led->cdev.brightness_set_blocking = ns2_led_set_blocking;
+	else
+		led->cdev.brightness_set = ns2_led_set;
+	led->num_modes = nmodes;
+	led->modval = modval;
+
+	ret = ns2_led_get_mode(led, &mode);
+	if (ret < 0)
+		return ret;
+
+	/* Set LED initial state. */
+	led->sata = (mode == NS_V2_LED_SATA) ? 1 : 0;
+	led->cdev.brightness = (mode == NS_V2_LED_OFF) ? LED_OFF : LED_FULL;
+
+	init_data.fwnode = node;
+
+	ret = devm_led_classdev_register_ext(dev, &led->cdev, &init_data);
+	if (ret)
+		dev_err(dev, "Failed to register LED for node %pfw\n", node);
+
+	return ret;
+}
+
+static int ns2_led_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct fwnode_handle *child;
+	struct ns2_led *leds;
+	int count;
+	int ret;
+
+	count = device_get_child_node_count(dev);
+	if (!count)
+		return -ENODEV;
+
+	leds = devm_kcalloc(dev, count, sizeof(*leds), GFP_KERNEL);
+	if (!leds)
+		return -ENOMEM;
+
+	device_for_each_child_node(dev, child) {
+		ret = ns2_led_register(dev, child, leds++);
+		if (ret) {
+			fwnode_handle_put(child);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static const struct of_device_id of_ns2_leds_match[] = {
+	{ .compatible = "lacie,ns2-leds", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, of_ns2_leds_match);
+
+static struct platform_driver ns2_led_driver = {
+	.probe		= ns2_led_probe,
+	.driver		= {
+		.name		= "leds-ns2",
+		.of_match_table	= 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");