drivers/platform/chrome/cros_ec_sysfs.c

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