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 static int bq24022_set_current_limit(struct regulator_dev *rdev,
  22                                         int min_uA, int max_uA)
  23 {
  24         struct platform_device *pdev = rdev_get_drvdata(rdev);
  25         struct bq24022_mach_info *pdata = pdev->dev.platform_data;
  26
  27         dev_dbg(&pdev->dev, "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 platform_device *pdev = rdev_get_drvdata(rdev);
  38         struct bq24022_mach_info *pdata = pdev->dev.platform_data;
  39
  40         return gpio_get_value(pdata->gpio_iset2) ? 500000 : 100000;
  41 }
  42
  43 static int bq24022_enable(struct regulator_dev *rdev)
  44 {
  45         struct platform_device *pdev = rdev_get_drvdata(rdev);
  46         struct bq24022_mach_info *pdata = pdev->dev.platform_data;
  47
  48         dev_dbg(&pdev->dev, "enabling charger\n");
  49
  50         gpio_set_value(pdata->gpio_nce, 0);
  51         return 0;
  52 }
  53
  54 static int bq24022_disable(struct regulator_dev *rdev)
  55 {
  56         struct platform_device *pdev = rdev_get_drvdata(rdev);
  57         struct bq24022_mach_info *pdata = pdev->dev.platform_data;
  58
  59         dev_dbg(&pdev->dev, "disabling charger\n");
  60
  61         gpio_set_value(pdata->gpio_nce, 1);
  62         return 0;
  63 }
  64
  65 static int bq24022_is_enabled(struct regulator_dev *rdev)
  66 {
  67         struct platform_device *pdev = rdev_get_drvdata(rdev);
  68         struct bq24022_mach_info *pdata = pdev->dev.platform_data;
  69
  70         return !gpio_get_value(pdata->gpio_nce);
  71 }
  72
  73 static struct regulator_ops bq24022_ops = {
  74         .set_current_limit = bq24022_set_current_limit,
  75         .get_current_limit = bq24022_get_current_limit,
  76         .enable            = bq24022_enable,
  77         .disable           = bq24022_disable,
  78         .is_enabled        = bq24022_is_enabled,
  79 };
  80
  81 static struct regulator_desc bq24022_desc = {
  82         .name  = "bq24022",
  83         .ops   = &bq24022_ops,
  84         .type  = REGULATOR_CURRENT,
  85 };
  86
  87 static int __init bq24022_probe(struct platform_device *pdev)
  88 {
  89         struct bq24022_mach_info *pdata = pdev->dev.platform_data;
  90         struct regulator_dev *bq24022;
  91         int ret;
  92
  93         if (!pdata || !pdata->gpio_nce || !pdata->gpio_iset2)
  94                 return -EINVAL;
  95
  96         ret = gpio_request(pdata->gpio_nce, "ncharge_en");
  97         if (ret) {
  98                 dev_dbg(&pdev->dev, "couldn't request nCE GPIO: %d\n",
  99                         pdata->gpio_nce);
 100                 goto err_ce;
 101         }
 102         ret = gpio_request(pdata->gpio_iset2, "charge_mode");
 103         if (ret) {
 104                 dev_dbg(&pdev->dev, "couldn't request ISET2 GPIO: %d\n",
 105                         pdata->gpio_iset2);
 106                 goto err_iset2;
 107         }
 108         ret = gpio_direction_output(pdata->gpio_iset2, 0);
 109         ret = gpio_direction_output(pdata->gpio_nce, 1);
 110
 111         bq24022 = regulator_register(&bq24022_desc, pdev);
 112         if (IS_ERR(bq24022)) {
 113                 dev_dbg(&pdev->dev, "couldn't register regulator\n");
 114                 ret = PTR_ERR(bq24022);
 115                 goto err_reg;
 116         }
 117         platform_set_drvdata(pdev, bq24022);
 118         dev_dbg(&pdev->dev, "registered regulator\n");
 119
 120         return 0;
 121 err_reg:
 122         gpio_free(pdata->gpio_iset2);
 123 err_iset2:
 124         gpio_free(pdata->gpio_nce);
 125 err_ce:
 126         return ret;
 127 }
 128
 129 static int __devexit bq24022_remove(struct platform_device *pdev)
 130 {
 131         struct bq24022_mach_info *pdata = pdev->dev.platform_data;
 132         struct regulator_dev *bq24022 = platform_get_drvdata(pdev);
 133
 134         regulator_unregister(bq24022);
 135         gpio_free(pdata->gpio_iset2);
 136         gpio_free(pdata->gpio_nce);
 137
 138         return 0;
 139 }
 140
 141 static struct platform_driver bq24022_driver = {
 142         .driver = {
 143                 .name = "bq24022",
 144         },
 145         .remove = __devexit_p(bq24022_remove),
 146 };
 147
 148 static int __init bq24022_init(void)
 149 {
 150         return platform_driver_probe(&bq24022_driver, bq24022_probe);
 151 }
 152
 153 static void __exit bq24022_exit(void)
 154 {
 155         platform_driver_unregister(&bq24022_driver);
 156 }
 157
 158 /*
 159  * make sure this is probed before gpio_vbus and pda_power,
 160  * but after asic3 or other GPIO expander drivers.
 161  */
 162 subsys_initcall(bq24022_init);
 163 module_exit(bq24022_exit);
 164
 165 MODULE_AUTHOR("Philipp Zabel");
 166 MODULE_DESCRIPTION("TI bq24022 Li-Ion Charger driver");
 167 MODULE_LICENSE("GPL");