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