diff options
Diffstat (limited to 'drivers/regulator/wm831x-isink.c')
| -rw-r--r-- | drivers/regulator/wm831x-isink.c | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/drivers/regulator/wm831x-isink.c b/drivers/regulator/wm831x-isink.c new file mode 100644 index 000000000000..1d8d9879d3a1 --- /dev/null +++ b/drivers/regulator/wm831x-isink.c @@ -0,0 +1,260 @@ +/* + * 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"); |