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