drivers/platform/chrome/cros_ec_sysfs.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 // Expose the ChromeOS EC through sysfs
   3 //
   4 // Copyright (C) 2014 Google, Inc.
   5
   6 #include <linux/ctype.h>
   7 #include <linux/delay.h>
   8 #include <linux/device.h>
   9 #include <linux/fs.h>
  10 #include <linux/kobject.h>
  11 #include <linux/mfd/cros_ec.h>
  12 #include <linux/mfd/cros_ec_commands.h>
  13 #include <linux/module.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/printk.h>
  16 #include <linux/slab.h>
  17 #include <linux/stat.h>
  18 #include <linux/types.h>
  19 #include <linux/uaccess.h>
  20
  21 #define DRV_NAME "cros-ec-sysfs"
  22
  23 /* Accessor functions */
  24
  25 static ssize_t reboot_show(struct device *dev,
  26                            struct device_attribute *attr, char *buf)
  27 {
  28         int count = 0;
  29
  30         count += scnprintf(buf + count, PAGE_SIZE - count,
  31                            "ro|rw|cancel|cold|disable-jump|hibernate");
  32         count += scnprintf(buf + count, PAGE_SIZE - count,
  33                            " [at-shutdown]\n");
  34         return count;
  35 }
  36
  37 static ssize_t reboot_store(struct device *dev,
  38                             struct device_attribute *attr,
  39                             const char *buf, size_t count)
  40 {
  41         static const struct {
  42                 const char * const str;
  43                 uint8_t cmd;
  44                 uint8_t flags;
  45         } words[] = {
  46                 {"cancel",       EC_REBOOT_CANCEL, 0},
  47                 {"ro",           EC_REBOOT_JUMP_RO, 0},
  48                 {"rw",           EC_REBOOT_JUMP_RW, 0},
  49                 {"cold",         EC_REBOOT_COLD, 0},
  50                 {"disable-jump", EC_REBOOT_DISABLE_JUMP, 0},
  51                 {"hibernate",    EC_REBOOT_HIBERNATE, 0},
  52                 {"at-shutdown",  -1, EC_REBOOT_FLAG_ON_AP_SHUTDOWN},
  53         };
  54         struct cros_ec_command *msg;
  55         struct ec_params_reboot_ec *param;
  56         int got_cmd = 0, offset = 0;
  57         int i;
  58         int ret;
  59         struct cros_ec_dev *ec = to_cros_ec_dev(dev);
  60
  61         msg = kmalloc(sizeof(*msg) + sizeof(*param), GFP_KERNEL);
  62         if (!msg)
  63                 return -ENOMEM;
  64
  65         param = (struct ec_params_reboot_ec *)msg->data;
  66
  67         param->flags = 0;
  68         while (1) {
  69                 /* Find word to start scanning */
  70                 while (buf[offset] && isspace(buf[offset]))
  71                         offset++;
  72                 if (!buf[offset])
  73                         break;
  74
  75                 for (i = 0; i < ARRAY_SIZE(words); i++) {
  76                         if (!strncasecmp(words[i].str, buf+offset,
  77                                          strlen(words[i].str))) {
  78                                 if (words[i].flags) {
  79                                         param->flags |= words[i].flags;
  80                                 } else {
  81                                         param->cmd = words[i].cmd;
  82                                         got_cmd = 1;
  83                                 }
  84                                 break;
  85                         }
  86                 }
  87
  88                 /* On to the next word, if any */
  89                 while (buf[offset] && !isspace(buf[offset]))
  90                         offset++;
  91         }
  92
  93         if (!got_cmd) {
  94                 count = -EINVAL;
  95                 goto exit;
  96         }
  97
  98         msg->version = 0;
  99         msg->command = EC_CMD_REBOOT_EC + ec->cmd_offset;
 100         msg->outsize = sizeof(*param);
 101         msg->insize = 0;
 102         ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
 103         if (ret < 0)
 104                 count = ret;
 105 exit:
 106         kfree(msg);
 107         return count;
 108 }
 109
 110 static ssize_t version_show(struct device *dev,
 111                             struct device_attribute *attr, char *buf)
 112 {
 113         static const char * const image_names[] = {"unknown", "RO", "RW"};
 114         struct ec_response_get_version *r_ver;
 115         struct ec_response_get_chip_info *r_chip;
 116         struct ec_response_board_version *r_board;
 117         struct cros_ec_command *msg;
 118         int ret;
 119         int count = 0;
 120         struct cros_ec_dev *ec = to_cros_ec_dev(dev);
 121
 122         msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
 123         if (!msg)
 124                 return -ENOMEM;
 125
 126         /* Get versions. RW may change. */
 127         msg->version = 0;
 128         msg->command = EC_CMD_GET_VERSION + ec->cmd_offset;
 129         msg->insize = sizeof(*r_ver);
 130         msg->outsize = 0;
 131         ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
 132         if (ret < 0) {
 133                 count = ret;
 134                 goto exit;
 135         }
 136         r_ver = (struct ec_response_get_version *)msg->data;
 137         /* Strings should be null-terminated, but let's be sure. */
 138         r_ver->version_string_ro[sizeof(r_ver->version_string_ro) - 1] = '\0';
 139         r_ver->version_string_rw[sizeof(r_ver->version_string_rw) - 1] = '\0';
 140         count += scnprintf(buf + count, PAGE_SIZE - count,
 141                            "RO version:    %s\n", r_ver->version_string_ro);
 142         count += scnprintf(buf + count, PAGE_SIZE - count,
 143                            "RW version:    %s\n", r_ver->version_string_rw);
 144         count += scnprintf(buf + count, PAGE_SIZE - count,
 145                            "Firmware copy: %s\n",
 146                            (r_ver->current_image < ARRAY_SIZE(image_names) ?
 147                             image_names[r_ver->current_image] : "?"));
 148
 149         /* Get build info. */
 150         msg->command = EC_CMD_GET_BUILD_INFO + ec->cmd_offset;
 151         msg->insize = EC_HOST_PARAM_SIZE;
 152         ret = cros_ec_cmd_xfer(ec->ec_dev, msg);
 153         if (ret < 0)
 154                 count += scnprintf(buf + count, PAGE_SIZE - count,
 155                                    "Build info:    XFER ERROR %d\n", ret);
 156         else if (msg->result != EC_RES_SUCCESS)
 157                 count += scnprintf(buf + count, PAGE_SIZE - count,
 158                                    "Build info:    EC error %d\n", msg->result);
 159         else {
 160                 msg->data[EC_HOST_PARAM_SIZE - 1] = '\0';
 161                 count += scnprintf(buf + count, PAGE_SIZE - count,
 162                                    "Build info:    %s\n", msg->data);
 163         }
 164
 165         /* Get chip info. */
 166         msg->command = EC_CMD_GET_CHIP_INFO + ec->cmd_offset;
 167         msg->insize = sizeof(*r_chip);
 168         ret = cros_ec_cmd_xfer(ec->ec_dev, msg);
 169         if (ret < 0)
 170                 count += scnprintf(buf + count, PAGE_SIZE - count,
 171                                    "Chip info:     XFER ERROR %d\n", ret);
 172         else if (msg->result != EC_RES_SUCCESS)
 173                 count += scnprintf(buf + count, PAGE_SIZE - count,
 174                                    "Chip info:     EC error %d\n", msg->result);
 175         else {
 176                 r_chip = (struct ec_response_get_chip_info *)msg->data;
 177
 178                 r_chip->vendor[sizeof(r_chip->vendor) - 1] = '\0';
 179                 r_chip->name[sizeof(r_chip->name) - 1] = '\0';
 180                 r_chip->revision[sizeof(r_chip->revision) - 1] = '\0';
 181                 count += scnprintf(buf + count, PAGE_SIZE - count,
 182                                    "Chip vendor:   %s\n", r_chip->vendor);
 183                 count += scnprintf(buf + count, PAGE_SIZE - count,
 184                                    "Chip name:     %s\n", r_chip->name);
 185                 count += scnprintf(buf + count, PAGE_SIZE - count,
 186                                    "Chip revision: %s\n", r_chip->revision);
 187         }
 188
 189         /* Get board version */
 190         msg->command = EC_CMD_GET_BOARD_VERSION + ec->cmd_offset;
 191         msg->insize = sizeof(*r_board);
 192         ret = cros_ec_cmd_xfer(ec->ec_dev, msg);
 193         if (ret < 0)
 194                 count += scnprintf(buf + count, PAGE_SIZE - count,
 195                                    "Board version: XFER ERROR %d\n", ret);
 196         else if (msg->result != EC_RES_SUCCESS)
 197                 count += scnprintf(buf + count, PAGE_SIZE - count,
 198                                    "Board version: EC error %d\n", msg->result);
 199         else {
 200                 r_board = (struct ec_response_board_version *)msg->data;
 201
 202                 count += scnprintf(buf + count, PAGE_SIZE - count,
 203                                    "Board version: %d\n",
 204                                    r_board->board_version);
 205         }
 206
 207 exit:
 208         kfree(msg);
 209         return count;
 210 }
 211
 212 static ssize_t flashinfo_show(struct device *dev,
 213                               struct device_attribute *attr, char *buf)
 214 {
 215         struct ec_response_flash_info *resp;
 216         struct cros_ec_command *msg;
 217         int ret;
 218         struct cros_ec_dev *ec = to_cros_ec_dev(dev);
 219
 220         msg = kmalloc(sizeof(*msg) + sizeof(*resp), GFP_KERNEL);
 221         if (!msg)
 222                 return -ENOMEM;
 223
 224         /* The flash info shouldn't ever change, but ask each time anyway. */
 225         msg->version = 0;
 226         msg->command = EC_CMD_FLASH_INFO + ec->cmd_offset;
 227         msg->insize = sizeof(*resp);
 228         msg->outsize = 0;
 229         ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
 230         if (ret < 0)
 231                 goto exit;
 232
 233         resp = (struct ec_response_flash_info *)msg->data;
 234
 235         ret = scnprintf(buf, PAGE_SIZE,
 236                         "FlashSize %d\nWriteSize %d\n"
 237                         "EraseSize %d\nProtectSize %d\n",
 238                         resp->flash_size, resp->write_block_size,
 239                         resp->erase_block_size, resp->protect_block_size);
 240 exit:
 241         kfree(msg);
 242         return ret;
 243 }
 244
 245 /* Keyboard wake angle control */
 246 static ssize_t kb_wake_angle_show(struct device *dev,
 247                                   struct device_attribute *attr, char *buf)
 248 {
 249         struct cros_ec_dev *ec = to_cros_ec_dev(dev);
 250         struct ec_response_motion_sense *resp;
 251         struct ec_params_motion_sense *param;
 252         struct cros_ec_command *msg;
 253         int ret;
 254
 255         msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
 256         if (!msg)
 257                 return -ENOMEM;
 258
 259         param = (struct ec_params_motion_sense *)msg->data;
 260         msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
 261         msg->version = 2;
 262         param->cmd = MOTIONSENSE_CMD_KB_WAKE_ANGLE;
 263         param->kb_wake_angle.data = EC_MOTION_SENSE_NO_VALUE;
 264         msg->outsize = sizeof(*param);
 265         msg->insize = sizeof(*resp);
 266
 267         ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
 268         if (ret < 0)
 269                 goto exit;
 270
 271         resp = (struct ec_response_motion_sense *)msg->data;
 272         ret = scnprintf(buf, PAGE_SIZE, "%d\n", resp->kb_wake_angle.ret);
 273 exit:
 274         kfree(msg);
 275         return ret;
 276 }
 277
 278 static ssize_t kb_wake_angle_store(struct device *dev,
 279                                    struct device_attribute *attr,
 280                                    const char *buf, size_t count)
 281 {
 282         struct cros_ec_dev *ec = to_cros_ec_dev(dev);
 283         struct ec_params_motion_sense *param;
 284         struct cros_ec_command *msg;
 285         u16 angle;
 286         int ret;
 287
 288         ret = kstrtou16(buf, 0, &angle);
 289         if (ret)
 290                 return ret;
 291
 292         msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
 293         if (!msg)
 294                 return -ENOMEM;
 295
 296         param = (struct ec_params_motion_sense *)msg->data;
 297         msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
 298         msg->version = 2;
 299         param->cmd = MOTIONSENSE_CMD_KB_WAKE_ANGLE;
 300         param->kb_wake_angle.data = angle;
 301         msg->outsize = sizeof(*param);
 302         msg->insize = sizeof(struct ec_response_motion_sense);
 303
 304         ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
 305         kfree(msg);
 306         if (ret < 0)
 307                 return ret;
 308         return count;
 309 }
 310
 311 /* Module initialization */
 312
 313 static DEVICE_ATTR_RW(reboot);
 314 static DEVICE_ATTR_RO(version);
 315 static DEVICE_ATTR_RO(flashinfo);
 316 static DEVICE_ATTR_RW(kb_wake_angle);
 317
 318 static struct attribute *__ec_attrs[] = {
 319         &dev_attr_kb_wake_angle.attr,
 320         &dev_attr_reboot.attr,
 321         &dev_attr_version.attr,
 322         &dev_attr_flashinfo.attr,
 323         NULL,
 324 };
 325
 326 static umode_t cros_ec_ctrl_visible(struct kobject *kobj,
 327                                     struct attribute *a, int n)
 328 {
 329         struct device *dev = container_of(kobj, struct device, kobj);
 330         struct cros_ec_dev *ec = to_cros_ec_dev(dev);
 331
 332         if (a == &dev_attr_kb_wake_angle.attr && !ec->has_kb_wake_angle)
 333                 return 0;
 334
 335         return a->mode;
 336 }
 337
 338 static struct attribute_group cros_ec_attr_group = {
 339         .attrs = __ec_attrs,
 340         .is_visible = cros_ec_ctrl_visible,
 341 };
 342
 343 static int cros_ec_sysfs_probe(struct platform_device *pd)
 344 {
 345         struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
 346         struct device *dev = &pd->dev;
 347         int ret;
 348
 349         ret = sysfs_create_group(&ec_dev->class_dev.kobj, &cros_ec_attr_group);
 350         if (ret < 0)
 351                 dev_err(dev, "failed to create attributes. err=%d\n", ret);
 352
 353         return ret;
 354 }
 355
 356 static int cros_ec_sysfs_remove(struct platform_device *pd)
 357 {
 358         struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
 359
 360         sysfs_remove_group(&ec_dev->class_dev.kobj, &cros_ec_attr_group);
 361
 362         return 0;
 363 }
 364
 365 static struct platform_driver cros_ec_sysfs_driver = {
 366         .driver = {
 367                 .name = DRV_NAME,
 368         },
 369         .probe = cros_ec_sysfs_probe,
 370         .remove = cros_ec_sysfs_remove,
 371 };
 372
 373 module_platform_driver(cros_ec_sysfs_driver);
 374
 375 MODULE_LICENSE("GPL");
 376 MODULE_DESCRIPTION("Expose the ChromeOS EC through sysfs");
 377 MODULE_ALIAS("platform:" DRV_NAME);