1/*
  2 * Support for TI bq24022 (bqTINY-II) Dual Input (USB/AC Adpater)
  3 * 1-Cell Li-Ion Charger connected via GPIOs.
  4 *
  5 * Copyright (c) 2008 Philipp Zabel
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License version 2 as
  9 * published by the Free Software Foundation.
 10 *
 11 */
 12
 13#include <linux/kernel.h>
 14#include <linux/init.h>
 15#include <linux/platform_device.h>
 16#include <linux/err.h>
 17#include <linux/gpio.h>
 18#include <linux/regulator/bq24022.h>
 19#include <linux/regulator/driver.h>
 20
 21
 22static int bq24022_set_current_limit(struct regulator_dev *rdev,
 23					int min_uA, int max_uA)
 24{
 25	struct bq24022_mach_info *pdata = rdev_get_drvdata(rdev);
 26
 27	dev_dbg(rdev_get_dev(rdev), "setting current limit to %s mA\n",
 28		max_uA >= 500000 ? "500" : "100");
 29
 30	/* REVISIT: maybe return error if min_uA != 0 ? */
 31	gpio_set_value(pdata->gpio_iset2, max_uA >= 500000);
 32	return 0;
 33}
 34
 35static int bq24022_get_current_limit(struct regulator_dev *rdev)
 36{
 37	struct bq24022_mach_info *pdata = rdev_get_drvdata(rdev);
 38
 39	return gpio_get_value(pdata->gpio_iset2) ? 500000 : 100000;
 40}
 41
 42static int bq24022_enable(struct regulator_dev *rdev)
 43{
 44	struct bq24022_mach_info *pdata = rdev_get_drvdata(rdev);
 45
 46	dev_dbg(rdev_get_dev(rdev), "enabling charger\n");
 47
 48	gpio_set_value(pdata->gpio_nce, 0);
 49	return 0;
 50}
 51
 52static int bq24022_disable(struct regulator_dev *rdev)
 53{
 54	struct bq24022_mach_info *pdata = rdev_get_drvdata(rdev);
 55
 56	dev_dbg(rdev_get_dev(rdev), "disabling charger\n");
 57
 58	gpio_set_value(pdata->gpio_nce, 1);
 59	return 0;
 60}
 61
 62static int bq24022_is_enabled(struct regulator_dev *rdev)
 63{
 64	struct bq24022_mach_info *pdata = rdev_get_drvdata(rdev);
 65
 66	return !gpio_get_value(pdata->gpio_nce);
 67}
 68
 69static struct regulator_ops bq24022_ops = {
 70	.set_current_limit = bq24022_set_current_limit,
 71	.get_current_limit = bq24022_get_current_limit,
 72	.enable            = bq24022_enable,
 73	.disable           = bq24022_disable,
 74	.is_enabled        = bq24022_is_enabled,
 75};
 76
 77static struct regulator_desc bq24022_desc = {
 78	.name  = "bq24022",
 79	.ops   = &bq24022_ops,
 80	.type  = REGULATOR_CURRENT,
 81	.owner = THIS_MODULE,
 82};
 83
 84static int __init bq24022_probe(struct platform_device *pdev)
 85{
 86	struct bq24022_mach_info *pdata = pdev->dev.platform_data;
 87	struct regulator_dev *bq24022;
 88	int ret;
 89
 90	if (!pdata || !pdata->gpio_nce || !pdata->gpio_iset2)
 91		return -EINVAL;
 92
 93	ret = gpio_request(pdata->gpio_nce, "ncharge_en");
 94	if (ret) {
 95		dev_dbg(&pdev->dev, "couldn't request nCE GPIO: %d\n",
 96			pdata->gpio_nce);
 97		goto err_ce;
 98	}
 99	ret = gpio_request(pdata->gpio_iset2, "charge_mode");
100	if (ret) {
101		dev_dbg(&pdev->dev, "couldn't request ISET2 GPIO: %d\n",
102			pdata->gpio_iset2);
103		goto err_iset2;
104	}
105	ret = gpio_direction_output(pdata->gpio_iset2, 0);
106	ret = gpio_direction_output(pdata->gpio_nce, 1);
107
108	bq24022 = regulator_register(&bq24022_desc, &pdev->dev,
109				     pdata->init_data, pdata);
110	if (IS_ERR(bq24022)) {
111		dev_dbg(&pdev->dev, "couldn't register regulator\n");
112		ret = PTR_ERR(bq24022);
113		goto err_reg;
114	}
115	platform_set_drvdata(pdev, bq24022);
116	dev_dbg(&pdev->dev, "registered regulator\n");
117
118	return 0;
119err_reg:
120	gpio_free(pdata->gpio_iset2);
121err_iset2:
122	gpio_free(pdata->gpio_nce);
123err_ce:
124	return ret;
125}
126
127static int __devexit bq24022_remove(struct platform_device *pdev)
128{
129	struct bq24022_mach_info *pdata = pdev->dev.platform_data;
130	struct regulator_dev *bq24022 = platform_get_drvdata(pdev);
131
132	regulator_unregister(bq24022);
133	gpio_free(pdata->gpio_iset2);
134	gpio_free(pdata->gpio_nce);
135
136	return 0;
137}
138
139static struct platform_driver bq24022_driver = {
140	.driver = {
141		.name = "bq24022",
142	},
143	.remove = __devexit_p(bq24022_remove),
144};
145
146static int __init bq24022_init(void)
147{
148	return platform_driver_probe(&bq24022_driver, bq24022_probe);
149}
150
151static void __exit bq24022_exit(void)
152{
153	platform_driver_unregister(&bq24022_driver);
154}
155
156module_init(bq24022_init);
157module_exit(bq24022_exit);
158
159MODULE_AUTHOR("Philipp Zabel");
160MODULE_DESCRIPTION("TI bq24022 Li-Ion Charger driver");
161MODULE_LICENSE("GPL");