drivers/regulator/bq24022.c

   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
  22 static 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
  35 static 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
  42 static 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
  52 static 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
  62 static int bq24022_is_enabled(struct regulator_dev *rdev)
  63 {
  64         struct platform_device *pdev = rdev_get_drvdata(rdev);
  65         struct bq24022_mach_info *pdata = pdev->dev.platform_data;
  66
  67         return !gpio_get_value(pdata->gpio_nce);
  68 }
  69
  70 static struct regulator_ops bq24022_ops = {
  71         .set_current_limit = bq24022_set_current_limit,
  72         .get_current_limit = bq24022_get_current_limit,
  73         .enable            = bq24022_enable,
  74         .disable           = bq24022_disable,
  75         .is_enabled        = bq24022_is_enabled,
  76 };
  77
  78 static struct regulator_desc bq24022_desc = {
  79         .name  = "bq24022",
  80         .ops   = &bq24022_ops,
  81         .type  = REGULATOR_CURRENT,
  82 };
  83
  84 static 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, pdata);
 109         if (IS_ERR(bq24022)) {
 110                 dev_dbg(&pdev->dev, "couldn't register regulator\n");
 111                 ret = PTR_ERR(bq24022);
 112                 goto err_reg;
 113         }
 114         platform_set_drvdata(pdev, bq24022);
 115         dev_dbg(&pdev->dev, "registered regulator\n");
 116
 117         return 0;
 118 err_reg:
 119         gpio_free(pdata->gpio_iset2);
 120 err_iset2:
 121         gpio_free(pdata->gpio_nce);
 122 err_ce:
 123         return ret;
 124 }
 125
 126 static int __devexit bq24022_remove(struct platform_device *pdev)
 127 {
 128         struct bq24022_mach_info *pdata = pdev->dev.platform_data;
 129         struct regulator_dev *bq24022 = platform_get_drvdata(pdev);
 130
 131         regulator_unregister(bq24022);
 132         gpio_free(pdata->gpio_iset2);
 133         gpio_free(pdata->gpio_nce);
 134
 135         return 0;
 136 }
 137
 138 static struct platform_driver bq24022_driver = {
 139         .driver = {
 140                 .name = "bq24022",
 141         },
 142         .remove = __devexit_p(bq24022_remove),
 143 };
 144
 145 static int __init bq24022_init(void)
 146 {
 147         return platform_driver_probe(&bq24022_driver, bq24022_probe);
 148 }
 149
 150 static void __exit bq24022_exit(void)
 151 {
 152         platform_driver_unregister(&bq24022_driver);
 153 }
 154
 155 /*
 156  * make sure this is probed before gpio_vbus and pda_power,
 157  * but after asic3 or other GPIO expander drivers.
 158  */
 159 subsys_initcall(bq24022_init);
 160 module_exit(bq24022_exit);
 161
 162 MODULE_AUTHOR("Philipp Zabel");
 163 MODULE_DESCRIPTION("TI bq24022 Li-Ion Charger driver");
 164 MODULE_LICENSE("GPL");