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         int ret = 0;
  34
  35         pr_debug("%s: blocked: %d\n", __func__, blocked);
  36
  37         if (blocked) {
  38                 if (rfkill_data->reg_enabled) {
  39                         regulator_disable(rfkill_data->vcc);
  40                         rfkill_data->reg_enabled = false;
  41                 }
  42         } else {
  43                 if (!rfkill_data->reg_enabled) {
  44                         ret = regulator_enable(rfkill_data->vcc);
  45                         if (!ret)
  46                                 rfkill_data->reg_enabled = true;
  47                 }
  48         }
  49
  50         pr_debug("%s: regulator_is_enabled after set_block: %d\n", __func__,
  51                 regulator_is_enabled(rfkill_data->vcc));
  52
  53         return ret;
  54 }
  55
  56 static struct rfkill_ops rfkill_regulator_ops = {
  57         .set_block = rfkill_regulator_set_block,
  58 };
  59
  60 static int rfkill_regulator_probe(struct platform_device *pdev)
  61 {
  62         struct rfkill_regulator_platform_data *pdata = pdev->dev.platform_data;
  63         struct rfkill_regulator_data *rfkill_data;
  64         struct regulator *vcc;
  65         struct rfkill *rf_kill;
  66         int ret = 0;
  67
  68         if (pdata == NULL) {
  69                 dev_err(&pdev->dev, "no platform data\n");
  70                 return -ENODEV;
  71         }
  72
  73         if (pdata->name == NULL || pdata->type == 0) {
  74                 dev_err(&pdev->dev, "invalid name or type in platform data\n");
  75                 return -EINVAL;
  76         }
  77
  78         vcc = regulator_get_exclusive(&pdev->dev, "vrfkill");
  79         if (IS_ERR(vcc)) {
  80                 dev_err(&pdev->dev, "Cannot get vcc for %s\n", pdata->name);
  81                 ret = PTR_ERR(vcc);
  82                 goto out;
  83         }
  84
  85         rfkill_data = kzalloc(sizeof(*rfkill_data), GFP_KERNEL);
  86         if (rfkill_data == NULL) {
  87                 ret = -ENOMEM;
  88                 goto err_data_alloc;
  89         }
  90
  91         rf_kill = rfkill_alloc(pdata->name, &pdev->dev,
  92                                 pdata->type,
  93                                 &rfkill_regulator_ops, rfkill_data);
  94         if (rf_kill == NULL) {
  95                 ret = -ENOMEM;
  96                 goto err_rfkill_alloc;
  97         }
  98
  99         if (regulator_is_enabled(vcc)) {
 100                 dev_dbg(&pdev->dev, "Regulator already enabled\n");
 101                 rfkill_data->reg_enabled = true;
 102         }
 103         rfkill_data->vcc = vcc;
 104         rfkill_data->rf_kill = rf_kill;
 105
 106         ret = rfkill_register(rf_kill);
 107         if (ret) {
 108                 dev_err(&pdev->dev, "Cannot register rfkill device\n");
 109                 goto err_rfkill_register;
 110         }
 111
 112         platform_set_drvdata(pdev, rfkill_data);
 113         dev_info(&pdev->dev, "%s initialized\n", pdata->name);
 114
 115         return 0;
 116
 117 err_rfkill_register:
 118         rfkill_destroy(rf_kill);
 119 err_rfkill_alloc:
 120         kfree(rfkill_data);
 121 err_data_alloc:
 122         regulator_put(vcc);
 123 out:
 124         return ret;
 125 }
 126
 127 static int rfkill_regulator_remove(struct platform_device *pdev)
 128 {
 129         struct rfkill_regulator_data *rfkill_data = platform_get_drvdata(pdev);
 130         struct rfkill *rf_kill = rfkill_data->rf_kill;
 131
 132         rfkill_unregister(rf_kill);
 133         rfkill_destroy(rf_kill);
 134         regulator_put(rfkill_data->vcc);
 135         kfree(rfkill_data);
 136
 137         return 0;
 138 }
 139
 140 static struct platform_driver rfkill_regulator_driver = {
 141         .probe = rfkill_regulator_probe,
 142         .remove = rfkill_regulator_remove,
 143         .driver = {
 144                 .name = "rfkill-regulator",
 145         },
 146 };
 147
 148 module_platform_driver(rfkill_regulator_driver);
 149
 150 MODULE_AUTHOR("Guiming Zhuo <gmzhuo@gmail.com>");
 151 MODULE_AUTHOR("Antonio Ospite <ospite@studenti.unina.it>");
 152 MODULE_DESCRIPTION("Regulator consumer driver for rfkill");
 153 MODULE_LICENSE("GPL");
 154 MODULE_ALIAS("platform:rfkill-regulator");