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