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");
  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_status(ec->ec_dev, msg);
 153         if (ret < 0) {
 154                 count += scnprintf(buf + count, PAGE_SIZE - count,
 155                                    "Build info:    XFER / EC ERROR %d / %d\n",
 156                                    ret, msg->result);
 157         } else {
 158                 msg->data[EC_HOST_PARAM_SIZE - 1] = '\0';
 159                 count += scnprintf(buf + count, PAGE_SIZE - count,
 160                                    "Build info:    %s\n", msg->data);
 161         }
 162
 163         /* Get chip info. */
 164         msg->command = EC_CMD_GET_CHIP_INFO + ec->cmd_offset;
 165         msg->insize = sizeof(*r_chip);
 166         ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
 167         if (ret < 0) {
 168                 count += scnprintf(buf + count, PAGE_SIZE - count,
 169                                    "Chip info:     XFER / EC ERROR %d / %d\n",
 170                                    ret, msg->result);
 171         } else {
 172                 r_chip = (struct ec_response_get_chip_info *)msg->data;
 173
 174                 r_chip->vendor[sizeof(r_chip->vendor) - 1] = '\0';
 175                 r_chip->name[sizeof(r_chip->name) - 1] = '\0';
 176                 r_chip->revision[sizeof(r_chip->revision) - 1] = '\0';
 177                 count += scnprintf(buf + count, PAGE_SIZE - count,
 178                                    "Chip vendor:   %s\n", r_chip->vendor);
 179                 count += scnprintf(buf + count, PAGE_SIZE - count,
 180                                    "Chip name:     %s\n", r_chip->name);
 181                 count += scnprintf(buf + count, PAGE_SIZE - count,
 182                                    "Chip revision: %s\n", r_chip->revision);
 183         }
 184
 185         /* Get board version */
 186         msg->command = EC_CMD_GET_BOARD_VERSION + ec->cmd_offset;
 187         msg->insize = sizeof(*r_board);
 188         ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
 189         if (ret < 0) {
 190                 count += scnprintf(buf + count, PAGE_SIZE - count,
 191                                    "Board version: XFER / EC ERROR %d / %d\n",
 192                                    ret, msg->result);
 193         } else {
 194                 r_board = (struct ec_response_board_version *)msg->data;
 195
 196                 count += scnprintf(buf + count, PAGE_SIZE - count,
 197                                    "Board version: %d\n",
 198                                    r_board->board_version);
 199         }
 200
 201 exit:
 202         kfree(msg);
 203         return count;
 204 }
 205
 206 static ssize_t flashinfo_show(struct device *dev,
 207                               struct device_attribute *attr, char *buf)
 208 {
 209         struct ec_response_flash_info *resp;
 210         struct cros_ec_command *msg;
 211         int ret;
 212         struct cros_ec_dev *ec = to_cros_ec_dev(dev);
 213
 214         msg = kmalloc(sizeof(*msg) + sizeof(*resp), GFP_KERNEL);
 215         if (!msg)
 216                 return -ENOMEM;
 217
 218         /* The flash info shouldn't ever change, but ask each time anyway. */
 219         msg->version = 0;
 220         msg->command = EC_CMD_FLASH_INFO + ec->cmd_offset;
 221         msg->insize = sizeof(*resp);
 222         msg->outsize = 0;
 223         ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
 224         if (ret < 0)
 225                 goto exit;
 226
 227         resp = (struct ec_response_flash_info *)msg->data;
 228
 229         ret = scnprintf(buf, PAGE_SIZE,
 230                         "FlashSize %d\nWriteSize %d\n"
 231                         "EraseSize %d\nProtectSize %d\n",
 232                         resp->flash_size, resp->write_block_size,
 233                         resp->erase_block_size, resp->protect_block_size);
 234 exit:
 235         kfree(msg);
 236         return ret;
 237 }
 238
 239 /* Keyboard wake angle control */
 240 static ssize_t kb_wake_angle_show(struct device *dev,
 241                                   struct device_attribute *attr, char *buf)
 242 {
 243         struct cros_ec_dev *ec = to_cros_ec_dev(dev);
 244         struct ec_response_motion_sense *resp;
 245         struct ec_params_motion_sense *param;
 246         struct cros_ec_command *msg;
 247         int ret;
 248
 249         msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
 250         if (!msg)
 251                 return -ENOMEM;
 252
 253         param = (struct ec_params_motion_sense *)msg->data;
 254         msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
 255         msg->version = 2;
 256         param->cmd = MOTIONSENSE_CMD_KB_WAKE_ANGLE;
 257         param->kb_wake_angle.data = EC_MOTION_SENSE_NO_VALUE;
 258         msg->outsize = sizeof(*param);
 259         msg->insize = sizeof(*resp);
 260
 261         ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
 262         if (ret < 0)
 263                 goto exit;
 264
 265         resp = (struct ec_response_motion_sense *)msg->data;
 266         ret = scnprintf(buf, PAGE_SIZE, "%d\n", resp->kb_wake_angle.ret);
 267 exit:
 268         kfree(msg);
 269         return ret;
 270 }
 271
 272 static ssize_t kb_wake_angle_store(struct device *dev,
 273                                    struct device_attribute *attr,
 274                                    const char *buf, size_t count)
 275 {
 276         struct cros_ec_dev *ec = to_cros_ec_dev(dev);
 277         struct ec_params_motion_sense *param;
 278         struct cros_ec_command *msg;
 279         u16 angle;
 280         int ret;
 281
 282         ret = kstrtou16(buf, 0, &angle);
 283         if (ret)
 284                 return ret;
 285
 286         msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
 287         if (!msg)
 288                 return -ENOMEM;
 289
 290         param = (struct ec_params_motion_sense *)msg->data;
 291         msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
 292         msg->version = 2;
 293         param->cmd = MOTIONSENSE_CMD_KB_WAKE_ANGLE;
 294         param->kb_wake_angle.data = angle;
 295         msg->outsize = sizeof(*param);
 296         msg->insize = sizeof(struct ec_response_motion_sense);
 297
 298         ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
 299         kfree(msg);
 300         if (ret < 0)
 301                 return ret;
 302         return count;
 303 }
 304
 305 /* Module initialization */
 306
 307 static DEVICE_ATTR_RW(reboot);
 308 static DEVICE_ATTR_RO(version);
 309 static DEVICE_ATTR_RO(flashinfo);
 310 static DEVICE_ATTR_RW(kb_wake_angle);
 311
 312 static struct attribute *__ec_attrs[] = {
 313         &dev_attr_kb_wake_angle.attr,
 314         &dev_attr_reboot.attr,
 315         &dev_attr_version.attr,
 316         &dev_attr_flashinfo.attr,
 317         NULL,
 318 };
 319
 320 static umode_t cros_ec_ctrl_visible(struct kobject *kobj,
 321                                     struct attribute *a, int n)
 322 {
 323         struct device *dev = kobj_to_dev(kobj);
 324         struct cros_ec_dev *ec = to_cros_ec_dev(dev);
 325
 326         if (a == &dev_attr_kb_wake_angle.attr && !ec->has_kb_wake_angle)
 327                 return 0;
 328
 329         return a->mode;
 330 }
 331
 332 static struct attribute_group cros_ec_attr_group = {
 333         .attrs = __ec_attrs,
 334         .is_visible = cros_ec_ctrl_visible,
 335 };
 336
 337 static int cros_ec_sysfs_probe(struct platform_device *pd)
 338 {
 339         struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
 340         struct device *dev = &pd->dev;
 341         int ret;
 342
 343         ret = sysfs_create_group(&ec_dev->class_dev.kobj, &cros_ec_attr_group);
 344         if (ret < 0)
 345                 dev_err(dev, "failed to create attributes. err=%d\n", ret);
 346
 347         return ret;
 348 }
 349
 350 static int cros_ec_sysfs_remove(struct platform_device *pd)
 351 {
 352         struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
 353
 354         sysfs_remove_group(&ec_dev->class_dev.kobj, &cros_ec_attr_group);
 355
 356         return 0;
 357 }
 358
 359 static struct platform_driver cros_ec_sysfs_driver = {
 360         .driver = {
 361                 .name = DRV_NAME,
 362         },
 363         .probe = cros_ec_sysfs_probe,
 364         .remove = cros_ec_sysfs_remove,
 365 };
 366
 367 module_platform_driver(cros_ec_sysfs_driver);
 368
 369 MODULE_LICENSE("GPL");
 370 MODULE_DESCRIPTION("Expose the ChromeOS EC through sysfs");
 371 MODULE_ALIAS("platform:" DRV_NAME);