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-rw-r--r--drivers/leds/leds-ns2.c284
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..1677d66d8
--- /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_kzalloc(dev, array_size(sizeof(*leds), count), 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");