drivers/power/supply/tps65217_charger.c

   1 /*
   2  * Battery charger driver for TI's tps65217
   3  *
   4  * Copyright (c) 2015, Collabora Ltd.
   5
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 /*
  20  * Battery charger driver for TI's tps65217
  21  */
  22 #include <linux/kernel.h>
  23 #include <linux/kthread.h>
  24 #include <linux/device.h>
  25 #include <linux/module.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/init.h>
  28 #include <linux/interrupt.h>
  29 #include <linux/slab.h>
  30 #include <linux/err.h>
  31 #include <linux/of.h>
  32 #include <linux/of_device.h>
  33 #include <linux/power_supply.h>
  34
  35 #include <linux/mfd/core.h>
  36 #include <linux/mfd/tps65217.h>
  37
  38 #define CHARGER_STATUS_PRESENT  (TPS65217_STATUS_ACPWR | TPS65217_STATUS_USBPWR)
  39 #define NUM_CHARGER_IRQS        2
  40 #define POLL_INTERVAL           (HZ * 2)
  41
  42 struct tps65217_charger {
  43         struct tps65217 *tps;
  44         struct device *dev;
  45         struct power_supply *ac;
  46
  47         int     online;
  48         int     prev_online;
  49
  50         struct task_struct      *poll_task;
  51 };
  52
  53 static enum power_supply_property tps65217_ac_props[] = {
  54         POWER_SUPPLY_PROP_ONLINE,
  55 };
  56
  57 static int tps65217_config_charger(struct tps65217_charger *charger)
  58 {
  59         int ret;
  60
  61         dev_dbg(charger->dev, "%s\n", __func__);
  62
  63         /*
  64          * tps65217 rev. G, p. 31 (see p. 32 for NTC schematic)
  65          *
  66          * The device can be configured to support a 100k NTC (B = 3960) by
  67          * setting the the NTC_TYPE bit in register CHGCONFIG1 to 1. However it
  68          * is not recommended to do so. In sleep mode, the charger continues
  69          * charging the battery, but all register values are reset to default
  70          * values. Therefore, the charger would get the wrong temperature
  71          * information. If 100k NTC setting is required, please contact the
  72          * factory.
  73          *
  74          * ATTENTION, conflicting information, from p. 46
  75          *
  76          * NTC TYPE (for battery temperature measurement)
  77          *   0 – 100k (curve 1, B = 3960)
  78          *   1 – 10k  (curve 2, B = 3480) (default on reset)
  79          *
  80          */
  81         ret = tps65217_clear_bits(charger->tps, TPS65217_REG_CHGCONFIG1,
  82                                   TPS65217_CHGCONFIG1_NTC_TYPE,
  83                                   TPS65217_PROTECT_NONE);
  84         if (ret) {
  85                 dev_err(charger->dev,
  86                         "failed to set 100k NTC setting: %d\n", ret);
  87                 return ret;
  88         }
  89
  90         return 0;
  91 }
  92
  93 static int tps65217_enable_charging(struct tps65217_charger *charger)
  94 {
  95         int ret;
  96
  97         /* charger already enabled */
  98         if (charger->online)
  99                 return 0;
 100
 101         dev_dbg(charger->dev, "%s: enable charging\n", __func__);
 102         ret = tps65217_set_bits(charger->tps, TPS65217_REG_CHGCONFIG1,
 103                                 TPS65217_CHGCONFIG1_CHG_EN,
 104                                 TPS65217_CHGCONFIG1_CHG_EN,
 105                                 TPS65217_PROTECT_NONE);
 106         if (ret) {
 107                 dev_err(charger->dev,
 108                         "%s: Error in writing CHG_EN in reg 0x%x: %d\n",
 109                         __func__, TPS65217_REG_CHGCONFIG1, ret);
 110                 return ret;
 111         }
 112
 113         charger->online = 1;
 114
 115         return 0;
 116 }
 117
 118 static int tps65217_ac_get_property(struct power_supply *psy,
 119                         enum power_supply_property psp,
 120                         union power_supply_propval *val)
 121 {
 122         struct tps65217_charger *charger = power_supply_get_drvdata(psy);
 123
 124         if (psp == POWER_SUPPLY_PROP_ONLINE) {
 125                 val->intval = charger->online;
 126                 return 0;
 127         }
 128         return -EINVAL;
 129 }
 130
 131 static irqreturn_t tps65217_charger_irq(int irq, void *dev)
 132 {
 133         int ret, val;
 134         struct tps65217_charger *charger = dev;
 135
 136         charger->prev_online = charger->online;
 137
 138         ret = tps65217_reg_read(charger->tps, TPS65217_REG_STATUS, &val);
 139         if (ret < 0) {
 140                 dev_err(charger->dev, "%s: Error in reading reg 0x%x\n",
 141                         __func__, TPS65217_REG_STATUS);
 142                 return IRQ_HANDLED;
 143         }
 144
 145         dev_dbg(charger->dev, "%s: 0x%x\n", __func__, val);
 146
 147         /* check for charger status bit */
 148         if (val & CHARGER_STATUS_PRESENT) {
 149                 ret = tps65217_enable_charging(charger);
 150                 if (ret) {
 151                         dev_err(charger->dev,
 152                                 "failed to enable charger: %d\n", ret);
 153                         return IRQ_HANDLED;
 154                 }
 155         } else {
 156                 charger->online = 0;
 157         }
 158
 159         if (charger->prev_online != charger->online)
 160                 power_supply_changed(charger->ac);
 161
 162         ret = tps65217_reg_read(charger->tps, TPS65217_REG_CHGCONFIG0, &val);
 163         if (ret < 0) {
 164                 dev_err(charger->dev, "%s: Error in reading reg 0x%x\n",
 165                         __func__, TPS65217_REG_CHGCONFIG0);
 166                 return IRQ_HANDLED;
 167         }
 168
 169         if (val & TPS65217_CHGCONFIG0_ACTIVE)
 170                 dev_dbg(charger->dev, "%s: charger is charging\n", __func__);
 171         else
 172                 dev_dbg(charger->dev,
 173                         "%s: charger is NOT charging\n", __func__);
 174
 175         return IRQ_HANDLED;
 176 }
 177
 178 static int tps65217_charger_poll_task(void *data)
 179 {
 180         set_freezable();
 181
 182         while (!kthread_should_stop()) {
 183                 schedule_timeout_interruptible(POLL_INTERVAL);
 184                 try_to_freeze();
 185                 tps65217_charger_irq(-1, data);
 186         }
 187         return 0;
 188 }
 189
 190 static const struct power_supply_desc tps65217_charger_desc = {
 191         .name                   = "tps65217-ac",
 192         .type                   = POWER_SUPPLY_TYPE_MAINS,
 193         .get_property           = tps65217_ac_get_property,
 194         .properties             = tps65217_ac_props,
 195         .num_properties         = ARRAY_SIZE(tps65217_ac_props),
 196 };
 197
 198 static int tps65217_charger_probe(struct platform_device *pdev)
 199 {
 200         struct tps65217 *tps = dev_get_drvdata(pdev->dev.parent);
 201         struct tps65217_charger *charger;
 202         struct power_supply_config cfg = {};
 203         struct task_struct *poll_task;
 204         int irq[NUM_CHARGER_IRQS];
 205         int ret;
 206         int i;
 207
 208         dev_dbg(&pdev->dev, "%s\n", __func__);
 209
 210         charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
 211         if (!charger)
 212                 return -ENOMEM;
 213
 214         platform_set_drvdata(pdev, charger);
 215         charger->tps = tps;
 216         charger->dev = &pdev->dev;
 217
 218         cfg.of_node = pdev->dev.of_node;
 219         cfg.drv_data = charger;
 220
 221         charger->ac = devm_power_supply_register(&pdev->dev,
 222                                                  &tps65217_charger_desc,
 223                                                  &cfg);
 224         if (IS_ERR(charger->ac)) {
 225                 dev_err(&pdev->dev, "failed: power supply register\n");
 226                 return PTR_ERR(charger->ac);
 227         }
 228
 229         irq[0] = platform_get_irq_byname(pdev, "USB");
 230         irq[1] = platform_get_irq_byname(pdev, "AC");
 231
 232         ret = tps65217_config_charger(charger);
 233         if (ret < 0) {
 234                 dev_err(charger->dev, "charger config failed, err %d\n", ret);
 235                 return ret;
 236         }
 237
 238         /* Create a polling thread if an interrupt is invalid */
 239         if (irq[0] < 0 || irq[1] < 0) {
 240                 poll_task = kthread_run(tps65217_charger_poll_task,
 241                                         charger, "ktps65217charger");
 242                 if (IS_ERR(poll_task)) {
 243                         ret = PTR_ERR(poll_task);
 244                         dev_err(charger->dev,
 245                                 "Unable to run kthread err %d\n", ret);
 246                         return ret;
 247                 }
 248
 249                 charger->poll_task = poll_task;
 250                 return 0;
 251         }
 252
 253         /* Create IRQ threads for charger interrupts */
 254         for (i = 0; i < NUM_CHARGER_IRQS; i++) {
 255                 ret = devm_request_threaded_irq(&pdev->dev, irq[i], NULL,
 256                                                 tps65217_charger_irq,
 257                                                 0, "tps65217-charger",
 258                                                 charger);
 259                 if (ret) {
 260                         dev_err(charger->dev,
 261                                 "Unable to register irq %d err %d\n", irq[i],
 262                                 ret);
 263                         return ret;
 264                 }
 265
 266                 /* Check current state */
 267                 tps65217_charger_irq(-1, charger);
 268         }
 269
 270         return 0;
 271 }
 272
 273 static int tps65217_charger_remove(struct platform_device *pdev)
 274 {
 275         struct tps65217_charger *charger = platform_get_drvdata(pdev);
 276
 277         if (charger->poll_task)
 278                 kthread_stop(charger->poll_task);
 279
 280         return 0;
 281 }
 282
 283 static const struct of_device_id tps65217_charger_match_table[] = {
 284         { .compatible = "ti,tps65217-charger", },
 285         { /* sentinel */ }
 286 };
 287 MODULE_DEVICE_TABLE(of, tps65217_charger_match_table);
 288
 289 static struct platform_driver tps65217_charger_driver = {
 290         .probe  = tps65217_charger_probe,
 291         .remove = tps65217_charger_remove,
 292         .driver = {
 293                 .name   = "tps65217-charger",
 294                 .of_match_table = of_match_ptr(tps65217_charger_match_table),
 295         },
 296
 297 };
 298 module_platform_driver(tps65217_charger_driver);
 299
 300 MODULE_LICENSE("GPL v2");
 301 MODULE_AUTHOR("Enric Balletbo Serra <enric.balletbo@collabora.com>");
 302 MODULE_DESCRIPTION("TPS65217 battery charger driver");