drivers/power/supply/tps65217_charger.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Battery charger driver for TI's tps65217
   3 //
   4 // Copyright (C) 2015 Collabora Ltd.
   5 // Author: Enric Balletbo i Serra <enric.balletbo@collabora.com>
   6
   7 /*
   8  * Battery charger driver for TI's tps65217
   9  */
  10 #include <linux/kernel.h>
  11 #include <linux/kthread.h>
  12 #include <linux/device.h>
  13 #include <linux/module.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/init.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/slab.h>
  18 #include <linux/err.h>
  19 #include <linux/of.h>
  20 #include <linux/power_supply.h>
  21
  22 #include <linux/mfd/core.h>
  23 #include <linux/mfd/tps65217.h>
  24
  25 #define CHARGER_STATUS_PRESENT  (TPS65217_STATUS_ACPWR | TPS65217_STATUS_USBPWR)
  26 #define NUM_CHARGER_IRQS        2
  27 #define POLL_INTERVAL           (HZ * 2)
  28
  29 struct tps65217_charger {
  30         struct tps65217 *tps;
  31         struct device *dev;
  32         struct power_supply *psy;
  33
  34         int     online;
  35         int     prev_online;
  36
  37         struct task_struct      *poll_task;
  38 };
  39
  40 static enum power_supply_property tps65217_charger_props[] = {
  41         POWER_SUPPLY_PROP_ONLINE,
  42 };
  43
  44 static int tps65217_config_charger(struct tps65217_charger *charger)
  45 {
  46         int ret;
  47
  48         /*
  49          * tps65217 rev. G, p. 31 (see p. 32 for NTC schematic)
  50          *
  51          * The device can be configured to support a 100k NTC (B = 3960) by
  52          * setting the NTC_TYPE bit in register CHGCONFIG1 to 1. However it
  53          * is not recommended to do so. In sleep mode, the charger continues
  54          * charging the battery, but all register values are reset to default
  55          * values. Therefore, the charger would get the wrong temperature
  56          * information. If 100k NTC setting is required, please contact the
  57          * factory.
  58          *
  59          * ATTENTION, conflicting information, from p. 46
  60          *
  61          * NTC TYPE (for battery temperature measurement)
  62          *   0 – 100k (curve 1, B = 3960)
  63          *   1 – 10k  (curve 2, B = 3480) (default on reset)
  64          *
  65          */
  66         ret = tps65217_clear_bits(charger->tps, TPS65217_REG_CHGCONFIG1,
  67                                   TPS65217_CHGCONFIG1_NTC_TYPE,
  68                                   TPS65217_PROTECT_NONE);
  69         if (ret) {
  70                 dev_err(charger->dev,
  71                         "failed to set 100k NTC setting: %d\n", ret);
  72                 return ret;
  73         }
  74
  75         return 0;
  76 }
  77
  78 static int tps65217_enable_charging(struct tps65217_charger *charger)
  79 {
  80         int ret;
  81
  82         /* charger already enabled */
  83         if (charger->online)
  84                 return 0;
  85
  86         dev_dbg(charger->dev, "%s: enable charging\n", __func__);
  87         ret = tps65217_set_bits(charger->tps, TPS65217_REG_CHGCONFIG1,
  88                                 TPS65217_CHGCONFIG1_CHG_EN,
  89                                 TPS65217_CHGCONFIG1_CHG_EN,
  90                                 TPS65217_PROTECT_NONE);
  91         if (ret) {
  92                 dev_err(charger->dev,
  93                         "%s: Error in writing CHG_EN in reg 0x%x: %d\n",
  94                         __func__, TPS65217_REG_CHGCONFIG1, ret);
  95                 return ret;
  96         }
  97
  98         charger->online = 1;
  99
 100         return 0;
 101 }
 102
 103 static int tps65217_charger_get_property(struct power_supply *psy,
 104                                          enum power_supply_property psp,
 105                                          union power_supply_propval *val)
 106 {
 107         struct tps65217_charger *charger = power_supply_get_drvdata(psy);
 108
 109         if (psp == POWER_SUPPLY_PROP_ONLINE) {
 110                 val->intval = charger->online;
 111                 return 0;
 112         }
 113         return -EINVAL;
 114 }
 115
 116 static irqreturn_t tps65217_charger_irq(int irq, void *dev)
 117 {
 118         int ret, val;
 119         struct tps65217_charger *charger = dev;
 120
 121         charger->prev_online = charger->online;
 122
 123         ret = tps65217_reg_read(charger->tps, TPS65217_REG_STATUS, &val);
 124         if (ret < 0) {
 125                 dev_err(charger->dev, "%s: Error in reading reg 0x%x\n",
 126                         __func__, TPS65217_REG_STATUS);
 127                 return IRQ_HANDLED;
 128         }
 129
 130         dev_dbg(charger->dev, "%s: 0x%x\n", __func__, val);
 131
 132         /* check for charger status bit */
 133         if (val & CHARGER_STATUS_PRESENT) {
 134                 ret = tps65217_enable_charging(charger);
 135                 if (ret) {
 136                         dev_err(charger->dev,
 137                                 "failed to enable charger: %d\n", ret);
 138                         return IRQ_HANDLED;
 139                 }
 140         } else {
 141                 charger->online = 0;
 142         }
 143
 144         if (charger->prev_online != charger->online)
 145                 power_supply_changed(charger->psy);
 146
 147         ret = tps65217_reg_read(charger->tps, TPS65217_REG_CHGCONFIG0, &val);
 148         if (ret < 0) {
 149                 dev_err(charger->dev, "%s: Error in reading reg 0x%x\n",
 150                         __func__, TPS65217_REG_CHGCONFIG0);
 151                 return IRQ_HANDLED;
 152         }
 153
 154         if (val & TPS65217_CHGCONFIG0_ACTIVE)
 155                 dev_dbg(charger->dev, "%s: charger is charging\n", __func__);
 156         else
 157                 dev_dbg(charger->dev,
 158                         "%s: charger is NOT charging\n", __func__);
 159
 160         return IRQ_HANDLED;
 161 }
 162
 163 static int tps65217_charger_poll_task(void *data)
 164 {
 165         set_freezable();
 166
 167         while (!kthread_should_stop()) {
 168                 schedule_timeout_interruptible(POLL_INTERVAL);
 169                 try_to_freeze();
 170                 tps65217_charger_irq(-1, data);
 171         }
 172         return 0;
 173 }
 174
 175 static const struct power_supply_desc tps65217_charger_desc = {
 176         .name                   = "tps65217-charger",
 177         .type                   = POWER_SUPPLY_TYPE_MAINS,
 178         .get_property           = tps65217_charger_get_property,
 179         .properties             = tps65217_charger_props,
 180         .num_properties         = ARRAY_SIZE(tps65217_charger_props),
 181 };
 182
 183 static int tps65217_charger_probe(struct platform_device *pdev)
 184 {
 185         struct tps65217 *tps = dev_get_drvdata(pdev->dev.parent);
 186         struct tps65217_charger *charger;
 187         struct power_supply_config cfg = {};
 188         struct task_struct *poll_task;
 189         int irq[NUM_CHARGER_IRQS];
 190         int ret;
 191         int i;
 192
 193         charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
 194         if (!charger)
 195                 return -ENOMEM;
 196
 197         platform_set_drvdata(pdev, charger);
 198         charger->tps = tps;
 199         charger->dev = &pdev->dev;
 200
 201         cfg.of_node = pdev->dev.of_node;
 202         cfg.drv_data = charger;
 203
 204         charger->psy = devm_power_supply_register(&pdev->dev,
 205                                                   &tps65217_charger_desc,
 206                                                   &cfg);
 207         if (IS_ERR(charger->psy)) {
 208                 dev_err(&pdev->dev, "failed: power supply register\n");
 209                 return PTR_ERR(charger->psy);
 210         }
 211
 212         irq[0] = platform_get_irq_byname(pdev, "USB");
 213         irq[1] = platform_get_irq_byname(pdev, "AC");
 214
 215         ret = tps65217_config_charger(charger);
 216         if (ret < 0) {
 217                 dev_err(charger->dev, "charger config failed, err %d\n", ret);
 218                 return ret;
 219         }
 220
 221         /* Create a polling thread if an interrupt is invalid */
 222         if (irq[0] < 0 || irq[1] < 0) {
 223                 poll_task = kthread_run(tps65217_charger_poll_task,
 224                                         charger, "ktps65217charger");
 225                 if (IS_ERR(poll_task)) {
 226                         ret = PTR_ERR(poll_task);
 227                         dev_err(charger->dev,
 228                                 "Unable to run kthread err %d\n", ret);
 229                         return ret;
 230                 }
 231
 232                 charger->poll_task = poll_task;
 233                 return 0;
 234         }
 235
 236         /* Create IRQ threads for charger interrupts */
 237         for (i = 0; i < NUM_CHARGER_IRQS; i++) {
 238                 ret = devm_request_threaded_irq(&pdev->dev, irq[i], NULL,
 239                                                 tps65217_charger_irq,
 240                                                 IRQF_SHARED, "tps65217-charger",
 241                                                 charger);
 242                 if (ret) {
 243                         dev_err(charger->dev,
 244                                 "Unable to register irq %d err %d\n", irq[i],
 245                                 ret);
 246                         return ret;
 247                 }
 248
 249                 /* Check current state */
 250                 tps65217_charger_irq(-1, charger);
 251         }
 252
 253         return 0;
 254 }
 255
 256 static void tps65217_charger_remove(struct platform_device *pdev)
 257 {
 258         struct tps65217_charger *charger = platform_get_drvdata(pdev);
 259
 260         if (charger->poll_task)
 261                 kthread_stop(charger->poll_task);
 262 }
 263
 264 static const struct of_device_id tps65217_charger_match_table[] = {
 265         { .compatible = "ti,tps65217-charger", },
 266         { /* sentinel */ }
 267 };
 268 MODULE_DEVICE_TABLE(of, tps65217_charger_match_table);
 269
 270 static struct platform_driver tps65217_charger_driver = {
 271         .probe  = tps65217_charger_probe,
 272         .remove = tps65217_charger_remove,
 273         .driver = {
 274                 .name   = "tps65217-charger",
 275                 .of_match_table = of_match_ptr(tps65217_charger_match_table),
 276         },
 277
 278 };
 279 module_platform_driver(tps65217_charger_driver);
 280
 281 MODULE_LICENSE("GPL v2");
 282 MODULE_AUTHOR("Enric Balletbo Serra <enric.balletbo@collabora.com>");
 283 MODULE_DESCRIPTION("TPS65217 battery charger driver");