drivers/power/goldfish_battery.c

   1 /*
   2  * Power supply driver for the goldfish emulator
   3  *
   4  * Copyright (C) 2008 Google, Inc.
   5  * Copyright (C) 2012 Intel, Inc.
   6  * Copyright (C) 2013 Intel, Inc.
   7  * Author: Mike Lockwood <lockwood@android.com>
   8  *
   9  * This software is licensed under the terms of the GNU General Public
  10  * License version 2, as published by the Free Software Foundation, and
  11  * may be copied, distributed, and modified under those terms.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/err.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/power_supply.h>
  23 #include <linux/types.h>
  24 #include <linux/pci.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/io.h>
  27
  28 struct goldfish_battery_data {
  29         void __iomem *reg_base;
  30         int irq;
  31         spinlock_t lock;
  32
  33         struct power_supply *battery;
  34         struct power_supply *ac;
  35 };
  36
  37 #define GOLDFISH_BATTERY_READ(data, addr) \
  38         (readl(data->reg_base + addr))
  39 #define GOLDFISH_BATTERY_WRITE(data, addr, x) \
  40         (writel(x, data->reg_base + addr))
  41
  42 /*
  43  * Temporary variable used between goldfish_battery_probe() and
  44  * goldfish_battery_open().
  45  */
  46 static struct goldfish_battery_data *battery_data;
  47
  48 enum {
  49         /* status register */
  50         BATTERY_INT_STATUS          = 0x00,
  51         /* set this to enable IRQ */
  52         BATTERY_INT_ENABLE          = 0x04,
  53
  54         BATTERY_AC_ONLINE       = 0x08,
  55         BATTERY_STATUS          = 0x0C,
  56         BATTERY_HEALTH          = 0x10,
  57         BATTERY_PRESENT         = 0x14,
  58         BATTERY_CAPACITY        = 0x18,
  59
  60         BATTERY_STATUS_CHANGED  = 1U << 0,
  61         AC_STATUS_CHANGED       = 1U << 1,
  62         BATTERY_INT_MASK        = BATTERY_STATUS_CHANGED | AC_STATUS_CHANGED,
  63 };
  64
  65
  66 static int goldfish_ac_get_property(struct power_supply *psy,
  67                         enum power_supply_property psp,
  68                         union power_supply_propval *val)
  69 {
  70         struct goldfish_battery_data *data = power_supply_get_drvdata(psy);
  71         int ret = 0;
  72
  73         switch (psp) {
  74         case POWER_SUPPLY_PROP_ONLINE:
  75                 val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_AC_ONLINE);
  76                 break;
  77         default:
  78                 ret = -EINVAL;
  79                 break;
  80         }
  81         return ret;
  82 }
  83
  84 static int goldfish_battery_get_property(struct power_supply *psy,
  85                                  enum power_supply_property psp,
  86                                  union power_supply_propval *val)
  87 {
  88         struct goldfish_battery_data *data = power_supply_get_drvdata(psy);
  89         int ret = 0;
  90
  91         switch (psp) {
  92         case POWER_SUPPLY_PROP_STATUS:
  93                 val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_STATUS);
  94                 break;
  95         case POWER_SUPPLY_PROP_HEALTH:
  96                 val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_HEALTH);
  97                 break;
  98         case POWER_SUPPLY_PROP_PRESENT:
  99                 val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_PRESENT);
 100                 break;
 101         case POWER_SUPPLY_PROP_TECHNOLOGY:
 102                 val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
 103                 break;
 104         case POWER_SUPPLY_PROP_CAPACITY:
 105                 val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_CAPACITY);
 106                 break;
 107         default:
 108                 ret = -EINVAL;
 109                 break;
 110         }
 111
 112         return ret;
 113 }
 114
 115 static enum power_supply_property goldfish_battery_props[] = {
 116         POWER_SUPPLY_PROP_STATUS,
 117         POWER_SUPPLY_PROP_HEALTH,
 118         POWER_SUPPLY_PROP_PRESENT,
 119         POWER_SUPPLY_PROP_TECHNOLOGY,
 120         POWER_SUPPLY_PROP_CAPACITY,
 121 };
 122
 123 static enum power_supply_property goldfish_ac_props[] = {
 124         POWER_SUPPLY_PROP_ONLINE,
 125 };
 126
 127 static irqreturn_t goldfish_battery_interrupt(int irq, void *dev_id)
 128 {
 129         unsigned long irq_flags;
 130         struct goldfish_battery_data *data = dev_id;
 131         uint32_t status;
 132
 133         spin_lock_irqsave(&data->lock, irq_flags);
 134
 135         /* read status flags, which will clear the interrupt */
 136         status = GOLDFISH_BATTERY_READ(data, BATTERY_INT_STATUS);
 137         status &= BATTERY_INT_MASK;
 138
 139         if (status & BATTERY_STATUS_CHANGED)
 140                 power_supply_changed(data->battery);
 141         if (status & AC_STATUS_CHANGED)
 142                 power_supply_changed(data->ac);
 143
 144         spin_unlock_irqrestore(&data->lock, irq_flags);
 145         return status ? IRQ_HANDLED : IRQ_NONE;
 146 }
 147
 148 static const struct power_supply_desc battery_desc = {
 149         .properties     = goldfish_battery_props,
 150         .num_properties = ARRAY_SIZE(goldfish_battery_props),
 151         .get_property   = goldfish_battery_get_property,
 152         .name           = "battery",
 153         .type           = POWER_SUPPLY_TYPE_BATTERY,
 154 };
 155
 156 static const struct power_supply_desc ac_desc = {
 157         .properties     = goldfish_ac_props,
 158         .num_properties = ARRAY_SIZE(goldfish_ac_props),
 159         .get_property   = goldfish_ac_get_property,
 160         .name           = "ac",
 161         .type           = POWER_SUPPLY_TYPE_MAINS,
 162 };
 163
 164 static int goldfish_battery_probe(struct platform_device *pdev)
 165 {
 166         int ret;
 167         struct resource *r;
 168         struct goldfish_battery_data *data;
 169         struct power_supply_config psy_cfg = {};
 170
 171         data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
 172         if (data == NULL)
 173                 return -ENOMEM;
 174
 175         spin_lock_init(&data->lock);
 176
 177         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 178         if (r == NULL) {
 179                 dev_err(&pdev->dev, "platform_get_resource failed\n");
 180                 return -ENODEV;
 181         }
 182
 183         data->reg_base = devm_ioremap(&pdev->dev, r->start, resource_size(r));
 184         if (data->reg_base == NULL) {
 185                 dev_err(&pdev->dev, "unable to remap MMIO\n");
 186                 return -ENOMEM;
 187         }
 188
 189         data->irq = platform_get_irq(pdev, 0);
 190         if (data->irq < 0) {
 191                 dev_err(&pdev->dev, "platform_get_irq failed\n");
 192                 return -ENODEV;
 193         }
 194
 195         ret = devm_request_irq(&pdev->dev, data->irq, goldfish_battery_interrupt,
 196                                                 IRQF_SHARED, pdev->name, data);
 197         if (ret)
 198                 return ret;
 199
 200         psy_cfg.drv_data = data;
 201
 202         data->ac = power_supply_register(&pdev->dev, &ac_desc, &psy_cfg);
 203         if (IS_ERR(data->ac))
 204                 return PTR_ERR(data->ac);
 205
 206         data->battery = power_supply_register(&pdev->dev, &battery_desc,
 207                                                 &psy_cfg);
 208         if (IS_ERR(data->battery)) {
 209                 power_supply_unregister(data->ac);
 210                 return PTR_ERR(data->battery);
 211         }
 212
 213         platform_set_drvdata(pdev, data);
 214         battery_data = data;
 215
 216         GOLDFISH_BATTERY_WRITE(data, BATTERY_INT_ENABLE, BATTERY_INT_MASK);
 217         return 0;
 218 }
 219
 220 static int goldfish_battery_remove(struct platform_device *pdev)
 221 {
 222         struct goldfish_battery_data *data = platform_get_drvdata(pdev);
 223
 224         power_supply_unregister(data->battery);
 225         power_supply_unregister(data->ac);
 226         battery_data = NULL;
 227         return 0;
 228 }
 229
 230 static struct platform_driver goldfish_battery_device = {
 231         .probe          = goldfish_battery_probe,
 232         .remove         = goldfish_battery_remove,
 233         .driver = {
 234                 .name = "goldfish-battery"
 235         }
 236 };
 237 module_platform_driver(goldfish_battery_device);
 238
 239 MODULE_AUTHOR("Mike Lockwood lockwood@android.com");
 240 MODULE_LICENSE("GPL");
 241 MODULE_DESCRIPTION("Battery driver for the Goldfish emulator");