drivers/power/pda_power.c

   1 /*
   2  * Common power driver for PDAs and phones with one or two external
   3  * power supplies (AC/USB) connected to main and backup batteries,
   4  * and optional builtin charger.
   5  *
   6  * Copyright © 2007 Anton Vorontsov <cbou@mail.ru>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/power_supply.h>
  17 #include <linux/pda_power.h>
  18 #include <linux/timer.h>
  19 #include <linux/jiffies.h>
  20
  21 static inline unsigned int get_irq_flags(struct resource *res)
  22 {
  23         unsigned int flags = IRQF_DISABLED | IRQF_SHARED;
  24
  25         flags |= res->flags & IRQF_TRIGGER_MASK;
  26
  27         return flags;
  28 }
  29
  30 static struct device *dev;
  31 static struct pda_power_pdata *pdata;
  32 static struct resource *ac_irq, *usb_irq;
  33 static struct timer_list charger_timer;
  34 static struct timer_list supply_timer;
  35
  36 static int pda_power_get_property(struct power_supply *psy,
  37                                   enum power_supply_property psp,
  38                                   union power_supply_propval *val)
  39 {
  40         switch (psp) {
  41         case POWER_SUPPLY_PROP_ONLINE:
  42                 if (psy->type == POWER_SUPPLY_TYPE_MAINS)
  43                         val->intval = pdata->is_ac_online ?
  44                                       pdata->is_ac_online() : 0;
  45                 else
  46                         val->intval = pdata->is_usb_online ?
  47                                       pdata->is_usb_online() : 0;
  48                 break;
  49         default:
  50                 return -EINVAL;
  51         }
  52         return 0;
  53 }
  54
  55 static enum power_supply_property pda_power_props[] = {
  56         POWER_SUPPLY_PROP_ONLINE,
  57 };
  58
  59 static char *pda_power_supplied_to[] = {
  60         "main-battery",
  61         "backup-battery",
  62 };
  63
  64 static struct power_supply pda_power_supplies[] = {
  65         {
  66                 .name = "ac",
  67                 .type = POWER_SUPPLY_TYPE_MAINS,
  68                 .supplied_to = pda_power_supplied_to,
  69                 .num_supplicants = ARRAY_SIZE(pda_power_supplied_to),
  70                 .properties = pda_power_props,
  71                 .num_properties = ARRAY_SIZE(pda_power_props),
  72                 .get_property = pda_power_get_property,
  73         },
  74         {
  75                 .name = "usb",
  76                 .type = POWER_SUPPLY_TYPE_USB,
  77                 .supplied_to = pda_power_supplied_to,
  78                 .num_supplicants = ARRAY_SIZE(pda_power_supplied_to),
  79                 .properties = pda_power_props,
  80                 .num_properties = ARRAY_SIZE(pda_power_props),
  81                 .get_property = pda_power_get_property,
  82         },
  83 };
  84
  85 static void update_charger(void)
  86 {
  87         if (!pdata->set_charge)
  88                 return;
  89
  90         if (pdata->is_ac_online && pdata->is_ac_online()) {
  91                 dev_dbg(dev, "charger on (AC)\n");
  92                 pdata->set_charge(PDA_POWER_CHARGE_AC);
  93         } else if (pdata->is_usb_online && pdata->is_usb_online()) {
  94                 dev_dbg(dev, "charger on (USB)\n");
  95                 pdata->set_charge(PDA_POWER_CHARGE_USB);
  96         } else {
  97                 dev_dbg(dev, "charger off\n");
  98                 pdata->set_charge(0);
  99         }
 100 }
 101
 102 static void supply_timer_func(unsigned long power_supply_ptr)
 103 {
 104         void *power_supply = (void *)power_supply_ptr;
 105
 106         power_supply_changed(power_supply);
 107 }
 108
 109 static void charger_timer_func(unsigned long power_supply_ptr)
 110 {
 111         update_charger();
 112
 113         /* Okay, charger set. Now wait a bit before notifying supplicants,
 114          * charge power should stabilize. */
 115         supply_timer.data = power_supply_ptr;
 116         mod_timer(&supply_timer,
 117                   jiffies + msecs_to_jiffies(pdata->wait_for_charger));
 118 }
 119
 120 static irqreturn_t power_changed_isr(int irq, void *power_supply)
 121 {
 122         /* Wait a bit before reading ac/usb line status and setting charger,
 123          * because ac/usb status readings may lag from irq. */
 124         charger_timer.data = (unsigned long)power_supply;
 125         mod_timer(&charger_timer,
 126                   jiffies + msecs_to_jiffies(pdata->wait_for_status));
 127         return IRQ_HANDLED;
 128 }
 129
 130 static int pda_power_probe(struct platform_device *pdev)
 131 {
 132         int ret = 0;
 133
 134         dev = &pdev->dev;
 135
 136         if (pdev->id != -1) {
 137                 dev_err(dev, "it's meaningless to register several "
 138                         "pda_powers; use id = -1\n");
 139                 ret = -EINVAL;
 140                 goto wrongid;
 141         }
 142
 143         pdata = pdev->dev.platform_data;
 144
 145         update_charger();
 146
 147         if (!pdata->wait_for_status)
 148                 pdata->wait_for_status = 500;
 149
 150         if (!pdata->wait_for_charger)
 151                 pdata->wait_for_charger = 500;
 152
 153         setup_timer(&charger_timer, charger_timer_func, 0);
 154         setup_timer(&supply_timer, supply_timer_func, 0);
 155
 156         ac_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "ac");
 157         usb_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "usb");
 158         if (!ac_irq && !usb_irq) {
 159                 dev_err(dev, "no ac/usb irq specified\n");
 160                 ret = -ENODEV;
 161                 goto noirqs;
 162         }
 163
 164         if (pdata->supplied_to) {
 165                 pda_power_supplies[0].supplied_to = pdata->supplied_to;
 166                 pda_power_supplies[1].supplied_to = pdata->supplied_to;
 167                 pda_power_supplies[0].num_supplicants = pdata->num_supplicants;
 168                 pda_power_supplies[1].num_supplicants = pdata->num_supplicants;
 169         }
 170
 171         ret = power_supply_register(&pdev->dev, &pda_power_supplies[0]);
 172         if (ret) {
 173                 dev_err(dev, "failed to register %s power supply\n",
 174                         pda_power_supplies[0].name);
 175                 goto supply0_failed;
 176         }
 177
 178         ret = power_supply_register(&pdev->dev, &pda_power_supplies[1]);
 179         if (ret) {
 180                 dev_err(dev, "failed to register %s power supply\n",
 181                         pda_power_supplies[1].name);
 182                 goto supply1_failed;
 183         }
 184
 185         if (ac_irq) {
 186                 ret = request_irq(ac_irq->start, power_changed_isr,
 187                                   get_irq_flags(ac_irq), ac_irq->name,
 188                                   &pda_power_supplies[0]);
 189                 if (ret) {
 190                         dev_err(dev, "request ac irq failed\n");
 191                         goto ac_irq_failed;
 192                 }
 193         }
 194
 195         if (usb_irq) {
 196                 ret = request_irq(usb_irq->start, power_changed_isr,
 197                                   get_irq_flags(usb_irq), usb_irq->name,
 198                                   &pda_power_supplies[1]);
 199                 if (ret) {
 200                         dev_err(dev, "request usb irq failed\n");
 201                         goto usb_irq_failed;
 202                 }
 203         }
 204
 205         goto success;
 206
 207 usb_irq_failed:
 208         if (ac_irq)
 209                 free_irq(ac_irq->start, &pda_power_supplies[0]);
 210 ac_irq_failed:
 211         power_supply_unregister(&pda_power_supplies[1]);
 212 supply1_failed:
 213         power_supply_unregister(&pda_power_supplies[0]);
 214 supply0_failed:
 215 noirqs:
 216 wrongid:
 217 success:
 218         return ret;
 219 }
 220
 221 static int pda_power_remove(struct platform_device *pdev)
 222 {
 223         if (usb_irq)
 224                 free_irq(usb_irq->start, &pda_power_supplies[1]);
 225         if (ac_irq)
 226                 free_irq(ac_irq->start, &pda_power_supplies[0]);
 227         del_timer_sync(&charger_timer);
 228         del_timer_sync(&supply_timer);
 229         power_supply_unregister(&pda_power_supplies[1]);
 230         power_supply_unregister(&pda_power_supplies[0]);
 231         return 0;
 232 }
 233
 234 static struct platform_driver pda_power_pdrv = {
 235         .driver = {
 236                 .name = "pda-power",
 237         },
 238         .probe = pda_power_probe,
 239         .remove = pda_power_remove,
 240 };
 241
 242 static int __init pda_power_init(void)
 243 {
 244         return platform_driver_register(&pda_power_pdrv);
 245 }
 246
 247 static void __exit pda_power_exit(void)
 248 {
 249         platform_driver_unregister(&pda_power_pdrv);
 250 }
 251
 252 module_init(pda_power_init);
 253 module_exit(pda_power_exit);
 254 MODULE_LICENSE("GPL");
 255 MODULE_AUTHOR("Anton Vorontsov <cbou@mail.ru>");