drivers/misc/mei/bus-fixup.c

   1 /*
   2  *
   3  * Intel Management Engine Interface (Intel MEI) Linux driver
   4  * Copyright (c) 2003-2013, Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/sched.h>
  19 #include <linux/module.h>
  20 #include <linux/moduleparam.h>
  21 #include <linux/device.h>
  22 #include <linux/slab.h>
  23 #include <linux/uuid.h>
  24
  25 #include <linux/mei_cl_bus.h>
  26
  27 #include "mei_dev.h"
  28 #include "client.h"
  29
  30 #define MEI_UUID_NFC_INFO UUID_LE(0xd2de1625, 0x382d, 0x417d, \
  31                         0x48, 0xa4, 0xef, 0xab, 0xba, 0x8a, 0x12, 0x06)
  32
  33 static const uuid_le mei_nfc_info_guid = MEI_UUID_NFC_INFO;
  34
  35 #define MEI_UUID_NFC_HCI UUID_LE(0x0bb17a78, 0x2a8e, 0x4c50, \
  36                         0x94, 0xd4, 0x50, 0x26, 0x67, 0x23, 0x77, 0x5c)
  37
  38 #define MEI_UUID_WD UUID_LE(0x05B79A6F, 0x4628, 0x4D7F, \
  39                             0x89, 0x9D, 0xA9, 0x15, 0x14, 0xCB, 0x32, 0xAB)
  40
  41 #define MEI_UUID_ANY NULL_UUID_LE
  42
  43 /**
  44  * number_of_connections - determine whether an client be on the bus
  45  *    according number of connections
  46  *    We support only clients:
  47  *       1. with single connection
  48  *       2. and fixed clients (max_number_of_connections == 0)
  49  *
  50  * @cldev: me clients device
  51  */
  52 static void number_of_connections(struct mei_cl_device *cldev)
  53 {
  54         dev_dbg(&cldev->dev, "running hook %s\n", __func__);
  55
  56         if (cldev->me_cl->props.max_number_of_connections > 1)
  57                 cldev->do_match = 0;
  58 }
  59
  60 /**
  61  * blacklist - blacklist a client from the bus
  62  *
  63  * @cldev: me clients device
  64  */
  65 static void blacklist(struct mei_cl_device *cldev)
  66 {
  67         dev_dbg(&cldev->dev, "running hook %s\n", __func__);
  68
  69         cldev->do_match = 0;
  70 }
  71
  72 /**
  73  * mei_wd - wd client on the bus, change protocol version
  74  *   as the API has changed.
  75  *
  76  * @cldev: me clients device
  77  */
  78 #if IS_ENABLED(CONFIG_INTEL_MEI_ME)
  79 #include <linux/pci.h>
  80 #include "hw-me-regs.h"
  81 static void mei_wd(struct mei_cl_device *cldev)
  82 {
  83         struct pci_dev *pdev = to_pci_dev(cldev->dev.parent);
  84
  85         dev_dbg(&cldev->dev, "running hook %s\n", __func__);
  86         if (pdev->device == MEI_DEV_ID_WPT_LP ||
  87             pdev->device == MEI_DEV_ID_SPT ||
  88             pdev->device == MEI_DEV_ID_SPT_H)
  89                 cldev->me_cl->props.protocol_version = 0x2;
  90
  91         cldev->do_match = 1;
  92 }
  93 #else
  94 static inline void mei_wd(struct mei_cl_device *cldev) {}
  95 #endif /* CONFIG_INTEL_MEI_ME */
  96
  97 struct mei_nfc_cmd {
  98         u8 command;
  99         u8 status;
 100         u16 req_id;
 101         u32 reserved;
 102         u16 data_size;
 103         u8 sub_command;
 104         u8 data[];
 105 } __packed;
 106
 107 struct mei_nfc_reply {
 108         u8 command;
 109         u8 status;
 110         u16 req_id;
 111         u32 reserved;
 112         u16 data_size;
 113         u8 sub_command;
 114         u8 reply_status;
 115         u8 data[];
 116 } __packed;
 117
 118 struct mei_nfc_if_version {
 119         u8 radio_version_sw[3];
 120         u8 reserved[3];
 121         u8 radio_version_hw[3];
 122         u8 i2c_addr;
 123         u8 fw_ivn;
 124         u8 vendor_id;
 125         u8 radio_type;
 126 } __packed;
 127
 128
 129 #define MEI_NFC_CMD_MAINTENANCE 0x00
 130 #define MEI_NFC_SUBCMD_IF_VERSION 0x01
 131
 132 /* Vendors */
 133 #define MEI_NFC_VENDOR_INSIDE 0x00
 134 #define MEI_NFC_VENDOR_NXP    0x01
 135
 136 /* Radio types */
 137 #define MEI_NFC_VENDOR_INSIDE_UREAD 0x00
 138 #define MEI_NFC_VENDOR_NXP_PN544    0x01
 139
 140 /**
 141  * mei_nfc_if_version - get NFC interface version
 142  *
 143  * @cl: host client (nfc info)
 144  * @ver: NFC interface version to be filled in
 145  *
 146  * Return: 0 on success; < 0 otherwise
 147  */
 148 static int mei_nfc_if_version(struct mei_cl *cl,
 149                               struct mei_nfc_if_version *ver)
 150 {
 151         struct mei_device *bus;
 152         struct mei_nfc_cmd cmd = {
 153                 .command = MEI_NFC_CMD_MAINTENANCE,
 154                 .data_size = 1,
 155                 .sub_command = MEI_NFC_SUBCMD_IF_VERSION,
 156         };
 157         struct mei_nfc_reply *reply = NULL;
 158         size_t if_version_length;
 159         int bytes_recv, ret;
 160
 161         bus = cl->dev;
 162
 163         WARN_ON(mutex_is_locked(&bus->device_lock));
 164
 165         ret = __mei_cl_send(cl, (u8 *)&cmd, sizeof(struct mei_nfc_cmd), 1);
 166         if (ret < 0) {
 167                 dev_err(bus->dev, "Could not send IF version cmd\n");
 168                 return ret;
 169         }
 170
 171         /* to be sure on the stack we alloc memory */
 172         if_version_length = sizeof(struct mei_nfc_reply) +
 173                 sizeof(struct mei_nfc_if_version);
 174
 175         reply = kzalloc(if_version_length, GFP_KERNEL);
 176         if (!reply)
 177                 return -ENOMEM;
 178
 179         ret = 0;
 180         bytes_recv = __mei_cl_recv(cl, (u8 *)reply, if_version_length);
 181         if (bytes_recv < 0 || bytes_recv < sizeof(struct mei_nfc_reply)) {
 182                 dev_err(bus->dev, "Could not read IF version\n");
 183                 ret = -EIO;
 184                 goto err;
 185         }
 186
 187         memcpy(ver, reply->data, sizeof(struct mei_nfc_if_version));
 188
 189         dev_info(bus->dev, "NFC MEI VERSION: IVN 0x%x Vendor ID 0x%x Type 0x%x\n",
 190                 ver->fw_ivn, ver->vendor_id, ver->radio_type);
 191
 192 err:
 193         kfree(reply);
 194         return ret;
 195 }
 196
 197 /**
 198  * mei_nfc_radio_name - derive nfc radio name from the interface version
 199  *
 200  * @ver: NFC radio version
 201  *
 202  * Return: radio name string
 203  */
 204 static const char *mei_nfc_radio_name(struct mei_nfc_if_version *ver)
 205 {
 206
 207         if (ver->vendor_id == MEI_NFC_VENDOR_INSIDE) {
 208                 if (ver->radio_type == MEI_NFC_VENDOR_INSIDE_UREAD)
 209                         return "microread";
 210         }
 211
 212         if (ver->vendor_id == MEI_NFC_VENDOR_NXP) {
 213                 if (ver->radio_type == MEI_NFC_VENDOR_NXP_PN544)
 214                         return "pn544";
 215         }
 216
 217         return NULL;
 218 }
 219
 220 /**
 221  * mei_nfc - The nfc fixup function. The function retrieves nfc radio
 222  *    name and set is as device attribute so we can load
 223  *    the proper device driver for it
 224  *
 225  * @cldev: me client device (nfc)
 226  */
 227 static void mei_nfc(struct mei_cl_device *cldev)
 228 {
 229         struct mei_device *bus;
 230         struct mei_cl *cl;
 231         struct mei_me_client *me_cl = NULL;
 232         struct mei_nfc_if_version ver;
 233         const char *radio_name = NULL;
 234         int ret;
 235
 236         bus = cldev->bus;
 237
 238         dev_dbg(&cldev->dev, "running hook %s\n", __func__);
 239
 240         mutex_lock(&bus->device_lock);
 241         /* we need to connect to INFO GUID */
 242         cl = mei_cl_alloc_linked(bus);
 243         if (IS_ERR(cl)) {
 244                 ret = PTR_ERR(cl);
 245                 cl = NULL;
 246                 dev_err(bus->dev, "nfc hook alloc failed %d\n", ret);
 247                 goto out;
 248         }
 249
 250         me_cl = mei_me_cl_by_uuid(bus, &mei_nfc_info_guid);
 251         if (!me_cl) {
 252                 ret = -ENOTTY;
 253                 dev_err(bus->dev, "Cannot find nfc info %d\n", ret);
 254                 goto out;
 255         }
 256
 257         ret = mei_cl_connect(cl, me_cl, NULL);
 258         if (ret < 0) {
 259                 dev_err(&cldev->dev, "Can't connect to the NFC INFO ME ret = %d\n",
 260                         ret);
 261                 goto out;
 262         }
 263
 264         mutex_unlock(&bus->device_lock);
 265
 266         ret = mei_nfc_if_version(cl, &ver);
 267         if (ret)
 268                 goto disconnect;
 269
 270         radio_name = mei_nfc_radio_name(&ver);
 271
 272         if (!radio_name) {
 273                 ret = -ENOENT;
 274                 dev_err(&cldev->dev, "Can't get the NFC interface version ret = %d\n",
 275                         ret);
 276                 goto disconnect;
 277         }
 278
 279         dev_dbg(bus->dev, "nfc radio %s\n", radio_name);
 280         strlcpy(cldev->name, radio_name, sizeof(cldev->name));
 281
 282 disconnect:
 283         mutex_lock(&bus->device_lock);
 284         if (mei_cl_disconnect(cl) < 0)
 285                 dev_err(bus->dev, "Can't disconnect the NFC INFO ME\n");
 286
 287         mei_cl_flush_queues(cl, NULL);
 288
 289 out:
 290         mei_cl_unlink(cl);
 291         mutex_unlock(&bus->device_lock);
 292         mei_me_cl_put(me_cl);
 293         kfree(cl);
 294
 295         if (ret)
 296                 cldev->do_match = 0;
 297
 298         dev_dbg(bus->dev, "end of fixup match = %d\n", cldev->do_match);
 299 }
 300
 301 #define MEI_FIXUP(_uuid, _hook) { _uuid, _hook }
 302
 303 static struct mei_fixup {
 304
 305         const uuid_le uuid;
 306         void (*hook)(struct mei_cl_device *cldev);
 307 } mei_fixups[] = {
 308         MEI_FIXUP(MEI_UUID_ANY, number_of_connections),
 309         MEI_FIXUP(MEI_UUID_NFC_INFO, blacklist),
 310         MEI_FIXUP(MEI_UUID_NFC_HCI, mei_nfc),
 311         MEI_FIXUP(MEI_UUID_WD, mei_wd),
 312 };
 313
 314 /**
 315  * mei_cldev_fixup - run fixup handlers
 316  *
 317  * @cldev: me client device
 318  */
 319 void mei_cl_bus_dev_fixup(struct mei_cl_device *cldev)
 320 {
 321         struct mei_fixup *f;
 322         const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
 323         int i;
 324
 325         for (i = 0; i < ARRAY_SIZE(mei_fixups); i++) {
 326
 327                 f = &mei_fixups[i];
 328                 if (uuid_le_cmp(f->uuid, MEI_UUID_ANY) == 0 ||
 329                     uuid_le_cmp(f->uuid, *uuid) == 0)
 330                         f->hook(cldev);
 331         }
 332 }
 333