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path: root/drivers/leds/leds-wm8350.c
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Diffstat (limited to 'drivers/leds/leds-wm8350.c')
-rw-r--r--drivers/leds/leds-wm8350.c286
1 files changed, 286 insertions, 0 deletions
diff --git a/drivers/leds/leds-wm8350.c b/drivers/leds/leds-wm8350.c
new file mode 100644
index 000000000..0d1218356
--- /dev/null
+++ b/drivers/leds/leds-wm8350.c
@@ -0,0 +1,286 @@
+/*
+ * LED driver for WM8350 driven LEDS.
+ *
+ * Copyright(C) 2007, 2008 Wolfson Microelectronics PLC.
+ *
+ * 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.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/leds.h>
+#include <linux/err.h>
+#include <linux/mfd/wm8350/pmic.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+/* Microamps */
+static const int isink_cur[] = {
+ 4,
+ 5,
+ 6,
+ 7,
+ 8,
+ 10,
+ 11,
+ 14,
+ 16,
+ 19,
+ 23,
+ 27,
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+ 109,
+ 130,
+ 154,
+ 183,
+ 218,
+ 259,
+ 308,
+ 367,
+ 436,
+ 518,
+ 616,
+ 733,
+ 872,
+ 1037,
+ 1233,
+ 1466,
+ 1744,
+ 2073,
+ 2466,
+ 2933,
+ 3487,
+ 4147,
+ 4932,
+ 5865,
+ 6975,
+ 8294,
+ 9864,
+ 11730,
+ 13949,
+ 16589,
+ 19728,
+ 23460,
+ 27899,
+ 33178,
+ 39455,
+ 46920,
+ 55798,
+ 66355,
+ 78910,
+ 93840,
+ 111596,
+ 132710,
+ 157820,
+ 187681,
+ 223191
+};
+
+#define to_wm8350_led(led_cdev) \
+ container_of(led_cdev, struct wm8350_led, cdev)
+
+static void wm8350_led_enable(struct wm8350_led *led)
+{
+ int ret;
+
+ if (led->enabled)
+ return;
+
+ ret = regulator_enable(led->isink);
+ if (ret != 0) {
+ dev_err(led->cdev.dev, "Failed to enable ISINK: %d\n", ret);
+ return;
+ }
+
+ ret = regulator_enable(led->dcdc);
+ if (ret != 0) {
+ dev_err(led->cdev.dev, "Failed to enable DCDC: %d\n", ret);
+ regulator_disable(led->isink);
+ return;
+ }
+
+ led->enabled = 1;
+}
+
+static void wm8350_led_disable(struct wm8350_led *led)
+{
+ int ret;
+
+ if (!led->enabled)
+ return;
+
+ ret = regulator_disable(led->dcdc);
+ if (ret != 0) {
+ dev_err(led->cdev.dev, "Failed to disable DCDC: %d\n", ret);
+ return;
+ }
+
+ ret = regulator_disable(led->isink);
+ if (ret != 0) {
+ dev_err(led->cdev.dev, "Failed to disable ISINK: %d\n", ret);
+ ret = regulator_enable(led->dcdc);
+ if (ret != 0)
+ dev_err(led->cdev.dev, "Failed to reenable DCDC: %d\n",
+ ret);
+ return;
+ }
+
+ led->enabled = 0;
+}
+
+static void led_work(struct work_struct *work)
+{
+ struct wm8350_led *led = container_of(work, struct wm8350_led, work);
+ int ret;
+ int uA;
+ unsigned long flags;
+
+ mutex_lock(&led->mutex);
+
+ spin_lock_irqsave(&led->value_lock, flags);
+
+ if (led->value == LED_OFF) {
+ spin_unlock_irqrestore(&led->value_lock, flags);
+ wm8350_led_disable(led);
+ goto out;
+ }
+
+ /* This scales linearly into the index of valid current
+ * settings which results in a linear scaling of perceived
+ * brightness due to the non-linear current settings provided
+ * by the hardware.
+ */
+ uA = (led->max_uA_index * led->value) / LED_FULL;
+ spin_unlock_irqrestore(&led->value_lock, flags);
+ BUG_ON(uA >= ARRAY_SIZE(isink_cur));
+
+ ret = regulator_set_current_limit(led->isink, isink_cur[uA],
+ isink_cur[uA]);
+ if (ret != 0)
+ dev_err(led->cdev.dev, "Failed to set %duA: %d\n",
+ isink_cur[uA], ret);
+
+ wm8350_led_enable(led);
+
+out:
+ mutex_unlock(&led->mutex);
+}
+
+static void wm8350_led_set(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ struct wm8350_led *led = to_wm8350_led(led_cdev);
+ unsigned long flags;
+
+ spin_lock_irqsave(&led->value_lock, flags);
+ led->value = value;
+ schedule_work(&led->work);
+ spin_unlock_irqrestore(&led->value_lock, flags);
+}
+
+static void wm8350_led_shutdown(struct platform_device *pdev)
+{
+ struct wm8350_led *led = platform_get_drvdata(pdev);
+
+ mutex_lock(&led->mutex);
+ led->value = LED_OFF;
+ wm8350_led_disable(led);
+ mutex_unlock(&led->mutex);
+}
+
+static int wm8350_led_probe(struct platform_device *pdev)
+{
+ struct regulator *isink, *dcdc;
+ struct wm8350_led *led;
+ struct wm8350_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
+ int i;
+
+ if (pdata == NULL) {
+ dev_err(&pdev->dev, "no platform data\n");
+ return -ENODEV;
+ }
+
+ if (pdata->max_uA < isink_cur[0]) {
+ dev_err(&pdev->dev, "Invalid maximum current %duA\n",
+ pdata->max_uA);
+ return -EINVAL;
+ }
+
+ isink = devm_regulator_get(&pdev->dev, "led_isink");
+ if (IS_ERR(isink)) {
+ dev_err(&pdev->dev, "%s: can't get ISINK\n", __func__);
+ return PTR_ERR(isink);
+ }
+
+ dcdc = devm_regulator_get(&pdev->dev, "led_vcc");
+ if (IS_ERR(dcdc)) {
+ dev_err(&pdev->dev, "%s: can't get DCDC\n", __func__);
+ return PTR_ERR(dcdc);
+ }
+
+ led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
+ if (led == NULL)
+ return -ENOMEM;
+
+ led->cdev.brightness_set = wm8350_led_set;
+ led->cdev.default_trigger = pdata->default_trigger;
+ led->cdev.name = pdata->name;
+ led->cdev.flags |= LED_CORE_SUSPENDRESUME;
+ led->enabled = regulator_is_enabled(isink);
+ led->isink = isink;
+ led->dcdc = dcdc;
+
+ for (i = 0; i < ARRAY_SIZE(isink_cur) - 1; i++)
+ if (isink_cur[i] >= pdata->max_uA)
+ break;
+ led->max_uA_index = i;
+ if (pdata->max_uA != isink_cur[i])
+ dev_warn(&pdev->dev,
+ "Maximum current %duA is not directly supported,"
+ " check platform data\n",
+ pdata->max_uA);
+
+ spin_lock_init(&led->value_lock);
+ mutex_init(&led->mutex);
+ INIT_WORK(&led->work, led_work);
+ led->value = LED_OFF;
+ platform_set_drvdata(pdev, led);
+
+ return led_classdev_register(&pdev->dev, &led->cdev);
+}
+
+static int wm8350_led_remove(struct platform_device *pdev)
+{
+ struct wm8350_led *led = platform_get_drvdata(pdev);
+
+ led_classdev_unregister(&led->cdev);
+ flush_work(&led->work);
+ wm8350_led_disable(led);
+ return 0;
+}
+
+static struct platform_driver wm8350_led_driver = {
+ .driver = {
+ .name = "wm8350-led",
+ },
+ .probe = wm8350_led_probe,
+ .remove = wm8350_led_remove,
+ .shutdown = wm8350_led_shutdown,
+};
+
+module_platform_driver(wm8350_led_driver);
+
+MODULE_AUTHOR("Mark Brown");
+MODULE_DESCRIPTION("WM8350 LED driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:wm8350-led");