--- /dev/null
+/*
+ * wm831x-isink.c -- Current sink driver for the WM831x series
+ *
+ * Copyright 2009 Wolfson Microelectronics PLC.
+ *
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+
+#include <linux/mfd/wm831x/core.h>
+#include <linux/mfd/wm831x/regulator.h>
+#include <linux/mfd/wm831x/pdata.h>
+
+#define WM831X_ISINK_MAX_NAME 7
+
+struct wm831x_isink {
+ char name[WM831X_ISINK_MAX_NAME];
+ struct regulator_desc desc;
+ int reg;
+ struct wm831x *wm831x;
+ struct regulator_dev *regulator;
+};
+
+static int wm831x_isink_enable(struct regulator_dev *rdev)
+{
+ struct wm831x_isink *isink = rdev_get_drvdata(rdev);
+ struct wm831x *wm831x = isink->wm831x;
+ int ret;
+
+ /* We have a two stage enable: first start the ISINK... */
+ ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA,
+ WM831X_CS1_ENA);
+ if (ret != 0)
+ return ret;
+
+ /* ...then enable drive */
+ ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_DRIVE,
+ WM831X_CS1_DRIVE);
+ if (ret != 0)
+ wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA, 0);
+
+ return ret;
+
+}
+
+static int wm831x_isink_disable(struct regulator_dev *rdev)
+{
+ struct wm831x_isink *isink = rdev_get_drvdata(rdev);
+ struct wm831x *wm831x = isink->wm831x;
+ int ret;
+
+ ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_DRIVE, 0);
+ if (ret < 0)
+ return ret;
+
+ ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA, 0);
+ if (ret < 0)
+ return ret;
+
+ return ret;
+
+}
+
+static int wm831x_isink_is_enabled(struct regulator_dev *rdev)
+{
+ struct wm831x_isink *isink = rdev_get_drvdata(rdev);
+ struct wm831x *wm831x = isink->wm831x;
+ int ret;
+
+ ret = wm831x_reg_read(wm831x, isink->reg);
+ if (ret < 0)
+ return ret;
+
+ if ((ret & (WM831X_CS1_ENA | WM831X_CS1_DRIVE)) ==
+ (WM831X_CS1_ENA | WM831X_CS1_DRIVE))
+ return 1;
+ else
+ return 0;
+}
+
+static int wm831x_isink_set_current(struct regulator_dev *rdev,
+ int min_uA, int max_uA)
+{
+ struct wm831x_isink *isink = rdev_get_drvdata(rdev);
+ struct wm831x *wm831x = isink->wm831x;
+ int ret, i;
+
+ for (i = 0; i < ARRAY_SIZE(wm831x_isinkv_values); i++) {
+ int val = wm831x_isinkv_values[i];
+ if (min_uA >= val && val <= max_uA) {
+ ret = wm831x_set_bits(wm831x, isink->reg,
+ WM831X_CS1_ISEL_MASK, i);
+ return ret;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static int wm831x_isink_get_current(struct regulator_dev *rdev)
+{
+ struct wm831x_isink *isink = rdev_get_drvdata(rdev);
+ struct wm831x *wm831x = isink->wm831x;
+ int ret;
+
+ ret = wm831x_reg_read(wm831x, isink->reg);
+ if (ret < 0)
+ return ret;
+
+ ret &= WM831X_CS1_ISEL_MASK;
+ if (ret > WM831X_ISINK_MAX_ISEL)
+ ret = WM831X_ISINK_MAX_ISEL;
+
+ return wm831x_isinkv_values[ret];
+}
+
+static struct regulator_ops wm831x_isink_ops = {
+ .is_enabled = wm831x_isink_is_enabled,
+ .enable = wm831x_isink_enable,
+ .disable = wm831x_isink_disable,
+ .set_current_limit = wm831x_isink_set_current,
+ .get_current_limit = wm831x_isink_get_current,
+};
+
+static irqreturn_t wm831x_isink_irq(int irq, void *data)
+{
+ struct wm831x_isink *isink = data;
+
+ regulator_notifier_call_chain(isink->regulator,
+ REGULATOR_EVENT_OVER_CURRENT,
+ NULL);
+
+ return IRQ_HANDLED;
+}
+
+
+static __devinit int wm831x_isink_probe(struct platform_device *pdev)
+{
+ struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
+ struct wm831x_pdata *pdata = wm831x->dev->platform_data;
+ struct wm831x_isink *isink;
+ int id = pdev->id % ARRAY_SIZE(pdata->isink);
+ struct resource *res;
+ int ret, irq;
+
+ dev_dbg(&pdev->dev, "Probing ISINK%d\n", id + 1);
+
+ if (pdata == NULL || pdata->isink[id] == NULL)
+ return -ENODEV;
+
+ isink = kzalloc(sizeof(struct wm831x_isink), GFP_KERNEL);
+ if (isink == NULL) {
+ dev_err(&pdev->dev, "Unable to allocate private data\n");
+ return -ENOMEM;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+ if (res == NULL) {
+ dev_err(&pdev->dev, "No I/O resource\n");
+ ret = -EINVAL;
+ goto err;
+ }
+ isink->reg = res->start;
+
+ /* For current parts this is correct; probably need to revisit
+ * in future.
+ */
+ snprintf(isink->name, sizeof(isink->name), "ISINK%d", id + 1);
+ isink->desc.name = isink->name;
+ isink->desc.id = id;
+ isink->desc.ops = &wm831x_isink_ops;
+ isink->desc.type = REGULATOR_CURRENT;
+ isink->desc.owner = THIS_MODULE;
+
+ isink->regulator = regulator_register(&isink->desc, &pdev->dev,
+ pdata->isink[id], isink);
+ if (IS_ERR(isink->regulator)) {
+ ret = PTR_ERR(isink->regulator);
+ dev_err(wm831x->dev, "Failed to register ISINK%d: %d\n",
+ id + 1, ret);
+ goto err;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ ret = wm831x_request_irq(wm831x, irq, wm831x_isink_irq,
+ IRQF_TRIGGER_RISING, isink->name,
+ isink);
+ if (ret != 0) {
+ dev_err(&pdev->dev, "Failed to request ISINK IRQ %d: %d\n",
+ irq, ret);
+ goto err_regulator;
+ }
+
+ platform_set_drvdata(pdev, isink);
+
+ return 0;
+
+err_regulator:
+ regulator_unregister(isink->regulator);
+err:
+ kfree(isink);
+ return ret;
+}
+
+static __devexit int wm831x_isink_remove(struct platform_device *pdev)
+{
+ struct wm831x_isink *isink = platform_get_drvdata(pdev);
+ struct wm831x *wm831x = isink->wm831x;
+
+ wm831x_free_irq(wm831x, platform_get_irq(pdev, 0), isink);
+
+ regulator_unregister(isink->regulator);
+ kfree(isink);
+
+ return 0;
+}
+
+static struct platform_driver wm831x_isink_driver = {
+ .probe = wm831x_isink_probe,
+ .remove = __devexit_p(wm831x_isink_remove),
+ .driver = {
+ .name = "wm831x-isink",
+ },
+};
+
+static int __init wm831x_isink_init(void)
+{
+ int ret;
+ ret = platform_driver_register(&wm831x_isink_driver);
+ if (ret != 0)
+ pr_err("Failed to register WM831x ISINK driver: %d\n", ret);
+
+ return ret;
+}
+subsys_initcall(wm831x_isink_init);
+
+static void __exit wm831x_isink_exit(void)
+{
+ platform_driver_unregister(&wm831x_isink_driver);
+}
+module_exit(wm831x_isink_exit);
+
+/* Module information */
+MODULE_AUTHOR("Mark Brown");
+MODULE_DESCRIPTION("WM831x current sink driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:wm831x-isink");