1 /* 2 * Generic battery driver code using IIO 3 * Copyright (C) 2012, Anish Kumar <anish198519851985@gmail.com> 4 * based on jz4740-battery.c 5 * based on s3c_adc_battery.c 6 * 7 * This file is subject to the terms and conditions of the GNU General Public 8 * License. See the file COPYING in the main directory of this archive for 9 * more details. 10 * 11 */ 12 #include <linux/interrupt.h> 13 #include <linux/platform_device.h> 14 #include <linux/power_supply.h> 15 #include <linux/gpio.h> 16 #include <linux/err.h> 17 #include <linux/timer.h> 18 #include <linux/jiffies.h> 19 #include <linux/errno.h> 20 #include <linux/init.h> 21 #include <linux/module.h> 22 #include <linux/slab.h> 23 #include <linux/iio/consumer.h> 24 #include <linux/iio/types.h> 25 #include <linux/power/generic-adc-battery.h> 26 27 #define JITTER_DEFAULT 10 /* hope 10ms is enough */ 28 29 enum gab_chan_type { 30 GAB_VOLTAGE = 0, 31 GAB_CURRENT, 32 GAB_POWER, 33 GAB_MAX_CHAN_TYPE 34 }; 35 36 /* 37 * gab_chan_name suggests the standard channel names for commonly used 38 * channel types. 39 */ 40 static const char *const gab_chan_name[] = { 41 [GAB_VOLTAGE] = "voltage", 42 [GAB_CURRENT] = "current", 43 [GAB_POWER] = "power", 44 }; 45 46 struct gab { 47 struct power_supply *psy; 48 struct power_supply_desc psy_desc; 49 struct iio_channel *channel[GAB_MAX_CHAN_TYPE]; 50 struct gab_platform_data *pdata; 51 struct delayed_work bat_work; 52 int level; 53 int status; 54 bool cable_plugged; 55 }; 56 57 static struct gab *to_generic_bat(struct power_supply *psy) 58 { 59 return power_supply_get_drvdata(psy); 60 } 61 62 static void gab_ext_power_changed(struct power_supply *psy) 63 { 64 struct gab *adc_bat = to_generic_bat(psy); 65 66 schedule_delayed_work(&adc_bat->bat_work, msecs_to_jiffies(0)); 67 } 68 69 static const enum power_supply_property gab_props[] = { 70 POWER_SUPPLY_PROP_STATUS, 71 POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN, 72 POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN, 73 POWER_SUPPLY_PROP_CHARGE_NOW, 74 POWER_SUPPLY_PROP_VOLTAGE_NOW, 75 POWER_SUPPLY_PROP_CURRENT_NOW, 76 POWER_SUPPLY_PROP_TECHNOLOGY, 77 POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN, 78 POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN, 79 POWER_SUPPLY_PROP_MODEL_NAME, 80 }; 81 82 /* 83 * This properties are set based on the received platform data and this 84 * should correspond one-to-one with enum chan_type. 85 */ 86 static const enum power_supply_property gab_dyn_props[] = { 87 POWER_SUPPLY_PROP_VOLTAGE_NOW, 88 POWER_SUPPLY_PROP_CURRENT_NOW, 89 POWER_SUPPLY_PROP_POWER_NOW, 90 }; 91 92 static bool gab_charge_finished(struct gab *adc_bat) 93 { 94 struct gab_platform_data *pdata = adc_bat->pdata; 95 bool ret = gpio_get_value(pdata->gpio_charge_finished); 96 bool inv = pdata->gpio_inverted; 97 98 if (!gpio_is_valid(pdata->gpio_charge_finished)) 99 return false; 100 return ret ^ inv; 101 } 102 103 static int gab_get_status(struct gab *adc_bat) 104 { 105 struct gab_platform_data *pdata = adc_bat->pdata; 106 struct power_supply_info *bat_info; 107 108 bat_info = &pdata->battery_info; 109 if (adc_bat->level == bat_info->charge_full_design) 110 return POWER_SUPPLY_STATUS_FULL; 111 return adc_bat->status; 112 } 113 114 static enum gab_chan_type gab_prop_to_chan(enum power_supply_property psp) 115 { 116 switch (psp) { 117 case POWER_SUPPLY_PROP_POWER_NOW: 118 return GAB_POWER; 119 case POWER_SUPPLY_PROP_VOLTAGE_NOW: 120 return GAB_VOLTAGE; 121 case POWER_SUPPLY_PROP_CURRENT_NOW: 122 return GAB_CURRENT; 123 default: 124 WARN_ON(1); 125 break; 126 } 127 return GAB_POWER; 128 } 129 130 static int read_channel(struct gab *adc_bat, enum power_supply_property psp, 131 int *result) 132 { 133 int ret; 134 int chan_index; 135 136 chan_index = gab_prop_to_chan(psp); 137 ret = iio_read_channel_processed(adc_bat->channel[chan_index], 138 result); 139 if (ret < 0) 140 pr_err("read channel error\n"); 141 return ret; 142 } 143 144 static int gab_get_property(struct power_supply *psy, 145 enum power_supply_property psp, union power_supply_propval *val) 146 { 147 struct gab *adc_bat; 148 struct gab_platform_data *pdata; 149 struct power_supply_info *bat_info; 150 int result = 0; 151 int ret = 0; 152 153 adc_bat = to_generic_bat(psy); 154 if (!adc_bat) { 155 dev_err(&psy->dev, "no battery infos ?!\n"); 156 return -EINVAL; 157 } 158 pdata = adc_bat->pdata; 159 bat_info = &pdata->battery_info; 160 161 switch (psp) { 162 case POWER_SUPPLY_PROP_STATUS: 163 val->intval = gab_get_status(adc_bat); 164 break; 165 case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN: 166 val->intval = 0; 167 break; 168 case POWER_SUPPLY_PROP_CHARGE_NOW: 169 val->intval = pdata->cal_charge(result); 170 break; 171 case POWER_SUPPLY_PROP_VOLTAGE_NOW: 172 case POWER_SUPPLY_PROP_CURRENT_NOW: 173 case POWER_SUPPLY_PROP_POWER_NOW: 174 ret = read_channel(adc_bat, psp, &result); 175 if (ret < 0) 176 goto err; 177 val->intval = result; 178 break; 179 case POWER_SUPPLY_PROP_TECHNOLOGY: 180 val->intval = bat_info->technology; 181 break; 182 case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN: 183 val->intval = bat_info->voltage_min_design; 184 break; 185 case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN: 186 val->intval = bat_info->voltage_max_design; 187 break; 188 case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN: 189 val->intval = bat_info->charge_full_design; 190 break; 191 case POWER_SUPPLY_PROP_MODEL_NAME: 192 val->strval = bat_info->name; 193 break; 194 default: 195 return -EINVAL; 196 } 197 err: 198 return ret; 199 } 200 201 static void gab_work(struct work_struct *work) 202 { 203 struct gab *adc_bat; 204 struct gab_platform_data *pdata; 205 struct delayed_work *delayed_work; 206 bool is_plugged; 207 int status; 208 209 delayed_work = to_delayed_work(work); 210 adc_bat = container_of(delayed_work, struct gab, bat_work); 211 pdata = adc_bat->pdata; 212 status = adc_bat->status; 213 214 is_plugged = power_supply_am_i_supplied(adc_bat->psy); 215 adc_bat->cable_plugged = is_plugged; 216 217 if (!is_plugged) 218 adc_bat->status = POWER_SUPPLY_STATUS_DISCHARGING; 219 else if (gab_charge_finished(adc_bat)) 220 adc_bat->status = POWER_SUPPLY_STATUS_NOT_CHARGING; 221 else 222 adc_bat->status = POWER_SUPPLY_STATUS_CHARGING; 223 224 if (status != adc_bat->status) 225 power_supply_changed(adc_bat->psy); 226 } 227 228 static irqreturn_t gab_charged(int irq, void *dev_id) 229 { 230 struct gab *adc_bat = dev_id; 231 struct gab_platform_data *pdata = adc_bat->pdata; 232 int delay; 233 234 delay = pdata->jitter_delay ? pdata->jitter_delay : JITTER_DEFAULT; 235 schedule_delayed_work(&adc_bat->bat_work, 236 msecs_to_jiffies(delay)); 237 return IRQ_HANDLED; 238 } 239 240 static int gab_probe(struct platform_device *pdev) 241 { 242 struct gab *adc_bat; 243 struct power_supply_desc *psy_desc; 244 struct power_supply_config psy_cfg = {}; 245 struct gab_platform_data *pdata = pdev->dev.platform_data; 246 enum power_supply_property *properties; 247 int ret = 0; 248 int chan; 249 int index = 0; 250 251 adc_bat = devm_kzalloc(&pdev->dev, sizeof(*adc_bat), GFP_KERNEL); 252 if (!adc_bat) { 253 dev_err(&pdev->dev, "failed to allocate memory\n"); 254 return -ENOMEM; 255 } 256 257 psy_cfg.drv_data = adc_bat; 258 psy_desc = &adc_bat->psy_desc; 259 psy_desc->name = pdata->battery_info.name; 260 261 /* bootup default values for the battery */ 262 adc_bat->cable_plugged = false; 263 adc_bat->status = POWER_SUPPLY_STATUS_DISCHARGING; 264 psy_desc->type = POWER_SUPPLY_TYPE_BATTERY; 265 psy_desc->get_property = gab_get_property; 266 psy_desc->external_power_changed = gab_ext_power_changed; 267 adc_bat->pdata = pdata; 268 269 /* 270 * copying the static properties and allocating extra memory for holding 271 * the extra configurable properties received from platform data. 272 */ 273 psy_desc->properties = kcalloc(ARRAY_SIZE(gab_props) + 274 ARRAY_SIZE(gab_chan_name), 275 sizeof(*psy_desc->properties), 276 GFP_KERNEL); 277 if (!psy_desc->properties) { 278 ret = -ENOMEM; 279 goto first_mem_fail; 280 } 281 282 memcpy(psy_desc->properties, gab_props, sizeof(gab_props)); 283 properties = (enum power_supply_property *) 284 ((char *)psy_desc->properties + sizeof(gab_props)); 285 286 /* 287 * getting channel from iio and copying the battery properties 288 * based on the channel supported by consumer device. 289 */ 290 for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) { 291 adc_bat->channel[chan] = iio_channel_get(&pdev->dev, 292 gab_chan_name[chan]); 293 if (IS_ERR(adc_bat->channel[chan])) { 294 ret = PTR_ERR(adc_bat->channel[chan]); 295 adc_bat->channel[chan] = NULL; 296 } else { 297 /* copying properties for supported channels only */ 298 memcpy(properties + sizeof(*(psy_desc->properties)) * index, 299 &gab_dyn_props[chan], 300 sizeof(gab_dyn_props[chan])); 301 index++; 302 } 303 } 304 305 /* none of the channels are supported so let's bail out */ 306 if (index == 0) { 307 ret = -ENODEV; 308 goto second_mem_fail; 309 } 310 311 /* 312 * Total number of properties is equal to static properties 313 * plus the dynamic properties.Some properties may not be set 314 * as come channels may be not be supported by the device.So 315 * we need to take care of that. 316 */ 317 psy_desc->num_properties = ARRAY_SIZE(gab_props) + index; 318 319 adc_bat->psy = power_supply_register(&pdev->dev, psy_desc, &psy_cfg); 320 if (IS_ERR(adc_bat->psy)) { 321 ret = PTR_ERR(adc_bat->psy); 322 goto err_reg_fail; 323 } 324 325 INIT_DELAYED_WORK(&adc_bat->bat_work, gab_work); 326 327 if (gpio_is_valid(pdata->gpio_charge_finished)) { 328 int irq; 329 ret = gpio_request(pdata->gpio_charge_finished, "charged"); 330 if (ret) 331 goto gpio_req_fail; 332 333 irq = gpio_to_irq(pdata->gpio_charge_finished); 334 ret = request_any_context_irq(irq, gab_charged, 335 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, 336 "battery charged", adc_bat); 337 if (ret < 0) 338 goto err_gpio; 339 } 340 341 platform_set_drvdata(pdev, adc_bat); 342 343 /* Schedule timer to check current status */ 344 schedule_delayed_work(&adc_bat->bat_work, 345 msecs_to_jiffies(0)); 346 return 0; 347 348 err_gpio: 349 gpio_free(pdata->gpio_charge_finished); 350 gpio_req_fail: 351 power_supply_unregister(adc_bat->psy); 352 err_reg_fail: 353 for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) { 354 if (adc_bat->channel[chan]) 355 iio_channel_release(adc_bat->channel[chan]); 356 } 357 second_mem_fail: 358 kfree(psy_desc->properties); 359 first_mem_fail: 360 return ret; 361 } 362 363 static int gab_remove(struct platform_device *pdev) 364 { 365 int chan; 366 struct gab *adc_bat = platform_get_drvdata(pdev); 367 struct gab_platform_data *pdata = adc_bat->pdata; 368 369 power_supply_unregister(adc_bat->psy); 370 371 if (gpio_is_valid(pdata->gpio_charge_finished)) { 372 free_irq(gpio_to_irq(pdata->gpio_charge_finished), adc_bat); 373 gpio_free(pdata->gpio_charge_finished); 374 } 375 376 for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) { 377 if (adc_bat->channel[chan]) 378 iio_channel_release(adc_bat->channel[chan]); 379 } 380 381 kfree(adc_bat->psy_desc.properties); 382 cancel_delayed_work(&adc_bat->bat_work); 383 return 0; 384 } 385 386 #ifdef CONFIG_PM 387 static int gab_suspend(struct device *dev) 388 { 389 struct gab *adc_bat = dev_get_drvdata(dev); 390 391 cancel_delayed_work_sync(&adc_bat->bat_work); 392 adc_bat->status = POWER_SUPPLY_STATUS_UNKNOWN; 393 return 0; 394 } 395 396 static int gab_resume(struct device *dev) 397 { 398 struct gab *adc_bat = dev_get_drvdata(dev); 399 struct gab_platform_data *pdata = adc_bat->pdata; 400 int delay; 401 402 delay = pdata->jitter_delay ? pdata->jitter_delay : JITTER_DEFAULT; 403 404 /* Schedule timer to check current status */ 405 schedule_delayed_work(&adc_bat->bat_work, 406 msecs_to_jiffies(delay)); 407 return 0; 408 } 409 410 static const struct dev_pm_ops gab_pm_ops = { 411 .suspend = gab_suspend, 412 .resume = gab_resume, 413 }; 414 415 #define GAB_PM_OPS (&gab_pm_ops) 416 #else 417 #define GAB_PM_OPS (NULL) 418 #endif 419 420 static struct platform_driver gab_driver = { 421 .driver = { 422 .name = "generic-adc-battery", 423 .pm = GAB_PM_OPS 424 }, 425 .probe = gab_probe, 426 .remove = gab_remove, 427 }; 428 module_platform_driver(gab_driver); 429 430 MODULE_AUTHOR("anish kumar <anish198519851985@gmail.com>"); 431 MODULE_DESCRIPTION("generic battery driver using IIO"); 432 MODULE_LICENSE("GPL"); 433