net/rfkill/rfkill-regulator.c

   1 /*
   2  * rfkill-regulator.c - Regulator consumer driver for rfkill
   3  *
   4  * Copyright (C) 2009  Guiming Zhuo <gmzhuo@gmail.com>
   5  * Copyright (C) 2011  Antonio Ospite <ospite@studenti.unina.it>
   6  *
   7  * Implementation inspired by leds-regulator driver.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  *
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/err.h>
  17 #include <linux/slab.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/regulator/consumer.h>
  20 #include <linux/rfkill.h>
  21 #include <linux/rfkill-regulator.h>
  22
  23 struct rfkill_regulator_data {
  24         struct rfkill *rf_kill;
  25         bool reg_enabled;
  26
  27         struct regulator *vcc;
  28 };
  29
  30 static int rfkill_regulator_set_block(void *data, bool blocked)
  31 {
  32         struct rfkill_regulator_data *rfkill_data = data;
  33
  34         pr_debug("%s: blocked: %d\n", __func__, blocked);
  35
  36         if (blocked) {
  37                 if (rfkill_data->reg_enabled) {
  38                         regulator_disable(rfkill_data->vcc);
  39                         rfkill_data->reg_enabled = false;
  40                 }
  41         } else {
  42                 if (!rfkill_data->reg_enabled) {
  43                         regulator_enable(rfkill_data->vcc);
  44                         rfkill_data->reg_enabled = true;
  45                 }
  46         }
  47
  48         pr_debug("%s: regulator_is_enabled after set_block: %d\n", __func__,
  49                 regulator_is_enabled(rfkill_data->vcc));
  50
  51         return 0;
  52 }
  53
  54 struct rfkill_ops rfkill_regulator_ops = {
  55         .set_block = rfkill_regulator_set_block,
  56 };
  57
  58 static int rfkill_regulator_probe(struct platform_device *pdev)
  59 {
  60         struct rfkill_regulator_platform_data *pdata = pdev->dev.platform_data;
  61         struct rfkill_regulator_data *rfkill_data;
  62         struct regulator *vcc;
  63         struct rfkill *rf_kill;
  64         int ret = 0;
  65
  66         if (pdata == NULL) {
  67                 dev_err(&pdev->dev, "no platform data\n");
  68                 return -ENODEV;
  69         }
  70
  71         if (pdata->name == NULL || pdata->type == 0) {
  72                 dev_err(&pdev->dev, "invalid name or type in platform data\n");
  73                 return -EINVAL;
  74         }
  75
  76         vcc = regulator_get_exclusive(&pdev->dev, "vrfkill");
  77         if (IS_ERR(vcc)) {
  78                 dev_err(&pdev->dev, "Cannot get vcc for %s\n", pdata->name);
  79                 ret = PTR_ERR(vcc);
  80                 goto out;
  81         }
  82
  83         rfkill_data = kzalloc(sizeof(*rfkill_data), GFP_KERNEL);
  84         if (rfkill_data == NULL) {
  85                 ret = -ENOMEM;
  86                 goto err_data_alloc;
  87         }
  88
  89         rf_kill = rfkill_alloc(pdata->name, &pdev->dev,
  90                                 pdata->type,
  91                                 &rfkill_regulator_ops, rfkill_data);
  92         if (rf_kill == NULL) {
  93                 ret = -ENOMEM;
  94                 goto err_rfkill_alloc;
  95         }
  96
  97         if (regulator_is_enabled(vcc)) {
  98                 dev_dbg(&pdev->dev, "Regulator already enabled\n");
  99                 rfkill_data->reg_enabled = true;
 100         }
 101         rfkill_data->vcc = vcc;
 102         rfkill_data->rf_kill = rf_kill;
 103
 104         ret = rfkill_register(rf_kill);
 105         if (ret) {
 106                 dev_err(&pdev->dev, "Cannot register rfkill device\n");
 107                 goto err_rfkill_register;
 108         }
 109
 110         platform_set_drvdata(pdev, rfkill_data);
 111         dev_info(&pdev->dev, "%s initialized\n", pdata->name);
 112
 113         return 0;
 114
 115 err_rfkill_register:
 116         rfkill_destroy(rf_kill);
 117 err_rfkill_alloc:
 118         kfree(rfkill_data);
 119 err_data_alloc:
 120         regulator_put(vcc);
 121 out:
 122         return ret;
 123 }
 124
 125 static int rfkill_regulator_remove(struct platform_device *pdev)
 126 {
 127         struct rfkill_regulator_data *rfkill_data = platform_get_drvdata(pdev);
 128         struct rfkill *rf_kill = rfkill_data->rf_kill;
 129
 130         rfkill_unregister(rf_kill);
 131         rfkill_destroy(rf_kill);
 132         regulator_put(rfkill_data->vcc);
 133         kfree(rfkill_data);
 134
 135         return 0;
 136 }
 137
 138 static struct platform_driver rfkill_regulator_driver = {
 139         .probe = rfkill_regulator_probe,
 140         .remove = rfkill_regulator_remove,
 141         .driver = {
 142                 .name = "rfkill-regulator",
 143                 .owner = THIS_MODULE,
 144         },
 145 };
 146
 147 module_platform_driver(rfkill_regulator_driver);
 148
 149 MODULE_AUTHOR("Guiming Zhuo <gmzhuo@gmail.com>");
 150 MODULE_AUTHOR("Antonio Ospite <ospite@studenti.unina.it>");
 151 MODULE_DESCRIPTION("Regulator consumer driver for rfkill");
 152 MODULE_LICENSE("GPL");
 153 MODULE_ALIAS("platform:rfkill-regulator");