Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Battery driver for a Greybus module. |
| 3 | * |
| 4 | * Copyright 2014 Google Inc. |
| 5 | * |
| 6 | * Released under the GPLv2 only. |
| 7 | */ |
| 8 | |
| 9 | #include <linux/kernel.h> |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/slab.h> |
| 12 | #include <linux/power_supply.h> |
| 13 | #include "greybus.h" |
| 14 | |
| 15 | struct gb_battery { |
| 16 | struct power_supply bat; |
Greg Kroah-Hartman | d47aa76 | 2014-09-07 15:54:24 -0700 | [diff] [blame] | 17 | // FIXME |
| 18 | // we will want to keep the battery stats in here as we will be getting |
| 19 | // updates from the SVC "on the fly" so we don't have to always go ask |
| 20 | // the battery for some information. Hopefully... |
Greg Kroah-Hartman | 2bb7eae | 2014-10-20 15:24:57 +0800 | [diff] [blame] | 21 | struct gb_connection *connection; |
| 22 | u8 version_major; |
| 23 | u8 version_minor; |
| 24 | |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 25 | }; |
| 26 | #define to_gb_battery(x) container_of(x, struct gb_battery, bat) |
| 27 | |
Greg Kroah-Hartman | c0855bf | 2014-10-21 14:31:24 +0800 | [diff] [blame] | 28 | /* Version of the Greybus battery protocol we support */ |
| 29 | #define GB_BATTERY_VERSION_MAJOR 0x00 |
| 30 | #define GB_BATTERY_VERSION_MINOR 0x01 |
| 31 | |
| 32 | /* Greybus battery request types */ |
| 33 | #define GB_BATTERY_TYPE_INVALID 0x00 |
| 34 | #define GB_BATTERY_TYPE_PROTOCOL_VERSION 0x01 |
| 35 | #define GB_BATTERY_TYPE_TECHNOLOGY 0x02 |
| 36 | #define GB_BATTERY_TYPE_STATUS 0x03 |
| 37 | #define GB_BATTERY_TYPE_MAX_VOLTAGE 0x04 |
| 38 | #define GB_BATTERY_TYPE_CAPACITY 0x05 |
| 39 | #define GB_BATTERY_TYPE_TEMPERATURE 0x06 |
| 40 | #define GB_BATTERY_TYPE_VOLTAGE 0x07 |
| 41 | |
| 42 | struct gb_battery_proto_version_response { |
| 43 | __u8 status; |
| 44 | __u8 major; |
| 45 | __u8 minor; |
| 46 | }; |
| 47 | |
| 48 | /* Should match up with battery types in linux/power_supply.h */ |
| 49 | #define GB_BATTERY_TECH_UNKNOWN 0x0000 |
| 50 | #define GB_BATTERY_TECH_NiMH 0x0001 |
| 51 | #define GB_BATTERY_TECH_LION 0x0002 |
| 52 | #define GB_BATTERY_TECH_LIPO 0x0003 |
| 53 | #define GB_BATTERY_TECH_LiFe 0x0004 |
| 54 | #define GB_BATTERY_TECH_NiCd 0x0005 |
| 55 | #define GB_BATTERY_TECH_LiMn 0x0006 |
| 56 | |
| 57 | struct gb_battery_technology_request { |
| 58 | __u8 status; |
| 59 | __le32 technology; |
| 60 | }; |
| 61 | |
| 62 | /* Should match up with battery status in linux/power_supply.h */ |
| 63 | #define GB_BATTERY_STATUS_UNKNOWN 0x0000 |
| 64 | #define GB_BATTERY_STATUS_CHARGING 0x0001 |
| 65 | #define GB_BATTERY_STATUS_DISCHARGING 0x0002 |
| 66 | #define GB_BATTERY_STATUS_NOT_CHARGING 0x0003 |
| 67 | #define GB_BATTERY_STATUS_FULL 0x0004 |
| 68 | |
| 69 | struct gb_battery_status_request { |
| 70 | __u8 status; |
| 71 | __le16 battery_status; |
| 72 | }; |
| 73 | |
| 74 | struct gb_battery_max_voltage_request { |
| 75 | __u8 status; |
| 76 | __le32 max_voltage; |
| 77 | }; |
| 78 | |
| 79 | struct gb_battery_capacity_request { |
| 80 | __u8 status; |
| 81 | __le32 capacity; |
| 82 | }; |
| 83 | |
| 84 | struct gb_battery_temperature_request { |
| 85 | __u8 status; |
| 86 | __le32 temperature; |
| 87 | }; |
| 88 | |
| 89 | struct gb_battery_voltage_request { |
| 90 | __u8 status; |
| 91 | __le32 voltage; |
| 92 | }; |
| 93 | |
| 94 | |
Greg Kroah-Hartman | c0855bf | 2014-10-21 14:31:24 +0800 | [diff] [blame] | 95 | static int battery_operation(struct gb_battery *gb, int type, |
| 96 | void *response, int response_size) |
| 97 | { |
| 98 | struct gb_connection *connection = gb->connection; |
| 99 | struct gb_operation *operation; |
| 100 | struct gb_battery_technology_request *fake_request; |
| 101 | u8 *local_response; |
| 102 | int ret; |
| 103 | |
| 104 | local_response = kmalloc(response_size, GFP_KERNEL); |
| 105 | if (!local_response) |
| 106 | return -ENOMEM; |
| 107 | |
| 108 | operation = gb_operation_create(connection, type, 0, response_size); |
| 109 | if (!operation) { |
| 110 | kfree(local_response); |
| 111 | return -ENOMEM; |
| 112 | } |
| 113 | |
| 114 | /* Synchronous operation--no callback */ |
| 115 | ret = gb_operation_request_send(operation, NULL); |
| 116 | if (ret) { |
| 117 | pr_err("version operation failed (%d)\n", ret); |
| 118 | goto out; |
| 119 | } |
| 120 | |
| 121 | /* |
| 122 | * We only want to look at the status, and all requests have the same |
| 123 | * layout for where the status is, so cast this to a random request so |
| 124 | * we can see the status easier. |
| 125 | */ |
| 126 | fake_request = (struct gb_battery_technology_request *)local_response; |
| 127 | if (fake_request->status) { |
| 128 | gb_connection_err(connection, "version response %hhu", |
| 129 | fake_request->status); |
| 130 | ret = -EIO; |
| 131 | } else { |
| 132 | /* Good request, so copy to the caller's buffer */ |
| 133 | memcpy(response, local_response, response_size); |
| 134 | } |
| 135 | out: |
| 136 | gb_operation_destroy(operation); |
Greg Kroah-Hartman | c9346e1 | 2014-10-21 15:51:53 +0800 | [diff] [blame] | 137 | kfree(local_response); |
Greg Kroah-Hartman | c0855bf | 2014-10-21 14:31:24 +0800 | [diff] [blame] | 138 | |
| 139 | return ret; |
| 140 | } |
| 141 | |
| 142 | /* |
| 143 | * This request only uses the connection field, and if successful, |
| 144 | * fills in the major and minor protocol version of the target. |
| 145 | */ |
| 146 | static int get_version(struct gb_battery *gb) |
| 147 | { |
| 148 | struct gb_battery_proto_version_response version_request; |
| 149 | int retval; |
| 150 | |
| 151 | retval = battery_operation(gb, GB_BATTERY_TYPE_PROTOCOL_VERSION, |
| 152 | &version_request, sizeof(version_request)); |
| 153 | if (retval) |
| 154 | return retval; |
| 155 | |
| 156 | if (version_request.major > GB_BATTERY_VERSION_MAJOR) { |
| 157 | pr_err("unsupported major version (%hhu > %hhu)\n", |
| 158 | version_request.major, GB_BATTERY_VERSION_MAJOR); |
| 159 | return -ENOTSUPP; |
| 160 | } |
| 161 | |
| 162 | gb->version_major = version_request.major; |
| 163 | gb->version_minor = version_request.minor; |
| 164 | return 0; |
| 165 | } |
| 166 | |
Greg Kroah-Hartman | 43789c3 | 2014-10-20 15:09:49 +0800 | [diff] [blame] | 167 | static int get_tech(struct gb_battery *gb) |
| 168 | { |
Greg Kroah-Hartman | c0855bf | 2014-10-21 14:31:24 +0800 | [diff] [blame] | 169 | struct gb_battery_technology_request tech_request; |
| 170 | u32 technology; |
| 171 | int retval; |
| 172 | |
| 173 | retval = battery_operation(gb, GB_BATTERY_TYPE_TECHNOLOGY, |
| 174 | &tech_request, sizeof(tech_request)); |
| 175 | if (retval) |
| 176 | return retval; |
| 177 | |
| 178 | /* |
Greg Kroah-Hartman | 0369a45 | 2014-10-21 16:25:13 +0800 | [diff] [blame] | 179 | * Map greybus values to power_supply values. Hopefully these are |
| 180 | * "identical" which should allow gcc to optomize the code away to |
| 181 | * nothing. |
Greg Kroah-Hartman | c0855bf | 2014-10-21 14:31:24 +0800 | [diff] [blame] | 182 | */ |
| 183 | technology = le32_to_cpu(tech_request.technology); |
Greg Kroah-Hartman | 0369a45 | 2014-10-21 16:25:13 +0800 | [diff] [blame] | 184 | switch (technology) { |
| 185 | case GB_BATTERY_TECH_NiMH: |
| 186 | technology = POWER_SUPPLY_TECHNOLOGY_NiMH; |
| 187 | break; |
| 188 | case GB_BATTERY_TECH_LION: |
| 189 | technology = POWER_SUPPLY_TECHNOLOGY_LION; |
| 190 | break; |
| 191 | case GB_BATTERY_TECH_LIPO: |
| 192 | technology = POWER_SUPPLY_TECHNOLOGY_LIPO; |
| 193 | break; |
| 194 | case GB_BATTERY_TECH_LiFe: |
| 195 | technology = POWER_SUPPLY_TECHNOLOGY_LiFe; |
| 196 | break; |
| 197 | case GB_BATTERY_TECH_NiCd: |
| 198 | technology = POWER_SUPPLY_TECHNOLOGY_NiCd; |
| 199 | break; |
| 200 | case GB_BATTERY_TECH_LiMn: |
| 201 | technology = POWER_SUPPLY_TECHNOLOGY_LiMn; |
| 202 | break; |
| 203 | case GB_BATTERY_TECH_UNKNOWN: |
| 204 | default: |
| 205 | technology = POWER_SUPPLY_TECHNOLOGY_UNKNOWN; |
| 206 | break; |
| 207 | } |
Greg Kroah-Hartman | c0855bf | 2014-10-21 14:31:24 +0800 | [diff] [blame] | 208 | return technology; |
Greg Kroah-Hartman | 43789c3 | 2014-10-20 15:09:49 +0800 | [diff] [blame] | 209 | } |
| 210 | |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 211 | static int get_status(struct gb_battery *gb) |
| 212 | { |
Greg Kroah-Hartman | c0855bf | 2014-10-21 14:31:24 +0800 | [diff] [blame] | 213 | struct gb_battery_status_request status_request; |
| 214 | u16 battery_status; |
| 215 | int retval; |
| 216 | |
| 217 | retval = battery_operation(gb, GB_BATTERY_TYPE_STATUS, |
| 218 | &status_request, sizeof(status_request)); |
| 219 | if (retval) |
| 220 | return retval; |
| 221 | |
| 222 | /* |
Greg Kroah-Hartman | 0369a45 | 2014-10-21 16:25:13 +0800 | [diff] [blame] | 223 | * Map greybus values to power_supply values. Hopefully these are |
| 224 | * "identical" which should allow gcc to optomize the code away to |
| 225 | * nothing. |
Greg Kroah-Hartman | c0855bf | 2014-10-21 14:31:24 +0800 | [diff] [blame] | 226 | */ |
| 227 | battery_status = le16_to_cpu(status_request.battery_status); |
Greg Kroah-Hartman | 0369a45 | 2014-10-21 16:25:13 +0800 | [diff] [blame] | 228 | switch (battery_status) { |
| 229 | case GB_BATTERY_STATUS_CHARGING: |
| 230 | battery_status = POWER_SUPPLY_STATUS_CHARGING; |
| 231 | break; |
| 232 | case GB_BATTERY_STATUS_DISCHARGING: |
| 233 | battery_status = POWER_SUPPLY_STATUS_DISCHARGING; |
| 234 | break; |
| 235 | case GB_BATTERY_STATUS_NOT_CHARGING: |
| 236 | battery_status = POWER_SUPPLY_STATUS_NOT_CHARGING; |
| 237 | break; |
| 238 | case GB_BATTERY_STATUS_FULL: |
| 239 | battery_status = POWER_SUPPLY_STATUS_FULL; |
| 240 | break; |
| 241 | case GB_BATTERY_STATUS_UNKNOWN: |
| 242 | default: |
| 243 | battery_status = POWER_SUPPLY_STATUS_UNKNOWN; |
| 244 | break; |
| 245 | } |
Greg Kroah-Hartman | c0855bf | 2014-10-21 14:31:24 +0800 | [diff] [blame] | 246 | return battery_status; |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 247 | } |
| 248 | |
Greg Kroah-Hartman | 43789c3 | 2014-10-20 15:09:49 +0800 | [diff] [blame] | 249 | static int get_max_voltage(struct gb_battery *gb) |
| 250 | { |
Greg Kroah-Hartman | c0855bf | 2014-10-21 14:31:24 +0800 | [diff] [blame] | 251 | struct gb_battery_max_voltage_request volt_request; |
| 252 | u32 max_voltage; |
| 253 | int retval; |
| 254 | |
| 255 | retval = battery_operation(gb, GB_BATTERY_TYPE_MAX_VOLTAGE, |
| 256 | &volt_request, sizeof(volt_request)); |
| 257 | if (retval) |
| 258 | return retval; |
| 259 | |
| 260 | max_voltage = le32_to_cpu(volt_request.max_voltage); |
| 261 | return max_voltage; |
Greg Kroah-Hartman | 43789c3 | 2014-10-20 15:09:49 +0800 | [diff] [blame] | 262 | } |
| 263 | |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 264 | static int get_capacity(struct gb_battery *gb) |
| 265 | { |
Greg Kroah-Hartman | c0855bf | 2014-10-21 14:31:24 +0800 | [diff] [blame] | 266 | struct gb_battery_capacity_request capacity_request; |
| 267 | u32 capacity; |
| 268 | int retval; |
| 269 | |
| 270 | retval = battery_operation(gb, GB_BATTERY_TYPE_CAPACITY, |
| 271 | &capacity_request, sizeof(capacity_request)); |
| 272 | if (retval) |
| 273 | return retval; |
| 274 | |
| 275 | capacity = le32_to_cpu(capacity_request.capacity); |
| 276 | return capacity; |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 277 | } |
| 278 | |
| 279 | static int get_temp(struct gb_battery *gb) |
| 280 | { |
Greg Kroah-Hartman | c0855bf | 2014-10-21 14:31:24 +0800 | [diff] [blame] | 281 | struct gb_battery_temperature_request temp_request; |
| 282 | u32 temperature; |
| 283 | int retval; |
| 284 | |
| 285 | retval = battery_operation(gb, GB_BATTERY_TYPE_TEMPERATURE, |
| 286 | &temp_request, sizeof(temp_request)); |
| 287 | if (retval) |
| 288 | return retval; |
| 289 | |
| 290 | temperature = le32_to_cpu(temp_request.temperature); |
| 291 | return temperature; |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 292 | } |
| 293 | |
| 294 | static int get_voltage(struct gb_battery *gb) |
| 295 | { |
Greg Kroah-Hartman | c0855bf | 2014-10-21 14:31:24 +0800 | [diff] [blame] | 296 | struct gb_battery_voltage_request voltage_request; |
| 297 | u32 voltage; |
| 298 | int retval; |
| 299 | |
| 300 | retval = battery_operation(gb, GB_BATTERY_TYPE_VOLTAGE, |
| 301 | &voltage_request, sizeof(voltage_request)); |
| 302 | if (retval) |
| 303 | return retval; |
| 304 | |
| 305 | voltage = le32_to_cpu(voltage_request.voltage); |
| 306 | return voltage; |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 307 | } |
| 308 | |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 309 | static int get_property(struct power_supply *b, |
| 310 | enum power_supply_property psp, |
| 311 | union power_supply_propval *val) |
| 312 | { |
| 313 | struct gb_battery *gb = to_gb_battery(b); |
| 314 | |
| 315 | switch (psp) { |
| 316 | case POWER_SUPPLY_PROP_TECHNOLOGY: |
Greg Kroah-Hartman | 43789c3 | 2014-10-20 15:09:49 +0800 | [diff] [blame] | 317 | val->intval = get_tech(gb); |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 318 | break; |
| 319 | |
| 320 | case POWER_SUPPLY_PROP_STATUS: |
| 321 | val->intval = get_status(gb); |
| 322 | break; |
| 323 | |
| 324 | case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN: |
Greg Kroah-Hartman | 43789c3 | 2014-10-20 15:09:49 +0800 | [diff] [blame] | 325 | val->intval = get_max_voltage(gb); |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 326 | break; |
| 327 | |
| 328 | case POWER_SUPPLY_PROP_CAPACITY: |
| 329 | val->intval = get_capacity(gb); |
| 330 | break; |
| 331 | |
| 332 | case POWER_SUPPLY_PROP_TEMP: |
| 333 | val->intval = get_temp(gb); |
| 334 | break; |
| 335 | |
| 336 | case POWER_SUPPLY_PROP_VOLTAGE_NOW: |
| 337 | val->intval = get_voltage(gb); |
| 338 | break; |
| 339 | |
| 340 | default: |
| 341 | return -EINVAL; |
| 342 | } |
| 343 | |
| 344 | return 0; |
| 345 | } |
| 346 | |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 347 | // FIXME - verify this list, odds are some can be removed and others added. |
| 348 | static enum power_supply_property battery_props[] = { |
| 349 | POWER_SUPPLY_PROP_TECHNOLOGY, |
| 350 | POWER_SUPPLY_PROP_STATUS, |
| 351 | POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN, |
| 352 | POWER_SUPPLY_PROP_CAPACITY, |
| 353 | POWER_SUPPLY_PROP_TEMP, |
| 354 | POWER_SUPPLY_PROP_VOLTAGE_NOW, |
| 355 | }; |
| 356 | |
Alex Elder | 3689f97 | 2014-10-27 06:04:30 -0500 | [diff] [blame] | 357 | static int gb_battery_connection_init(struct gb_connection *connection) |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 358 | { |
| 359 | struct gb_battery *gb; |
| 360 | struct power_supply *b; |
| 361 | int retval; |
| 362 | |
| 363 | gb = kzalloc(sizeof(*gb), GFP_KERNEL); |
| 364 | if (!gb) |
| 365 | return -ENOMEM; |
| 366 | |
Greg Kroah-Hartman | 6507cce | 2014-10-27 17:58:54 +0800 | [diff] [blame] | 367 | gb->connection = connection; |
Alex Elder | fb305c3 | 2014-10-20 23:01:03 -0500 | [diff] [blame] | 368 | connection->private = gb; |
Greg Kroah-Hartman | 2bb7eae | 2014-10-20 15:24:57 +0800 | [diff] [blame] | 369 | |
Greg Kroah-Hartman | c0855bf | 2014-10-21 14:31:24 +0800 | [diff] [blame] | 370 | /* Check the version */ |
| 371 | retval = get_version(gb); |
| 372 | if (retval) { |
| 373 | kfree(gb); |
| 374 | return retval; |
| 375 | } |
| 376 | |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 377 | b = &gb->bat; |
| 378 | // FIXME - get a better (i.e. unique) name |
| 379 | // FIXME - anything else needs to be set? |
| 380 | b->name = "gb_battery"; |
| 381 | b->type = POWER_SUPPLY_TYPE_BATTERY, |
| 382 | b->properties = battery_props, |
| 383 | b->num_properties = ARRAY_SIZE(battery_props), |
| 384 | b->get_property = get_property, |
| 385 | |
Greg Kroah-Hartman | 2bb7eae | 2014-10-20 15:24:57 +0800 | [diff] [blame] | 386 | retval = power_supply_register(&connection->interface->gmod->dev, b); |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 387 | if (retval) { |
| 388 | kfree(gb); |
| 389 | return retval; |
| 390 | } |
Greg Kroah-Hartman | 33ea3a3 | 2014-09-07 15:39:34 -0700 | [diff] [blame] | 391 | |
| 392 | return 0; |
| 393 | } |
| 394 | |
Alex Elder | 3689f97 | 2014-10-27 06:04:30 -0500 | [diff] [blame] | 395 | static void gb_battery_connection_exit(struct gb_connection *connection) |
Alex Elder | 697e55d | 2014-10-20 23:01:04 -0500 | [diff] [blame] | 396 | { |
| 397 | struct gb_battery *gb = connection->private; |
| 398 | |
| 399 | power_supply_unregister(&gb->bat); |
| 400 | kfree(gb); |
| 401 | } |
| 402 | |
Alex Elder | 19d03de | 2014-11-05 16:12:53 -0600 | [diff] [blame] | 403 | static struct gb_protocol battery_protocol = { |
| 404 | .id = GREYBUS_PROTOCOL_BATTERY, |
| 405 | .major = 0, |
| 406 | .minor = 1, |
Alex Elder | 5d9fd7e | 2014-11-05 16:12:54 -0600 | [diff] [blame] | 407 | .connection_init = gb_battery_connection_init, |
| 408 | .connection_exit = gb_battery_connection_exit, |
Alex Elder | f8fb05e | 2014-11-05 16:12:55 -0600 | [diff] [blame] | 409 | .request_recv = NULL, /* no incoming requests */ |
Alex Elder | 19d03de | 2014-11-05 16:12:53 -0600 | [diff] [blame] | 410 | }; |
| 411 | |
| 412 | bool gb_battery_protocol_init(void) |
| 413 | { |
| 414 | return gb_protocol_register(&battery_protocol); |
| 415 | } |
| 416 | |
| 417 | void gb_battery_protocol_exit(void) |
| 418 | { |
| 419 | gb_protocol_deregister(&battery_protocol); |
| 420 | } |