drivers/i2c/busses/i2c-nforce2.c

   1 /*
   2     SMBus driver for nVidia nForce2 MCP
   3
   4     Added nForce3 Pro 150  Thomas Leibold <thomas@plx.com>,
   5         Ported to 2.5 Patrick Dreker <patrick@dreker.de>,
   6     Copyright (c) 2003  Hans-Frieder Vogt <hfvogt@arcor.de>,
   7     Based on
   8     SMBus 2.0 driver for AMD-8111 IO-Hub
   9     Copyright (c) 2002 Vojtech Pavlik
  10
  11     This program is free software; you can redistribute it and/or modify
  12     it under the terms of the GNU General Public License as published by
  13     the Free Software Foundation; either version 2 of the License, or
  14     (at your option) any later version.
  15
  16     This program is distributed in the hope that it will be useful,
  17     but WITHOUT ANY WARRANTY; without even the implied warranty of
  18     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19     GNU General Public License for more details.
  20 */
  21
  22 /*
  23     SUPPORTED DEVICES           PCI ID
  24     nForce2 MCP                 0064
  25     nForce2 Ultra 400 MCP       0084
  26     nForce3 Pro150 MCP          00D4
  27     nForce3 250Gb MCP           00E4
  28     nForce4 MCP                 0052
  29     nForce4 MCP-04              0034
  30     nForce MCP51                0264
  31     nForce MCP55                0368
  32     nForce MCP61                03EB
  33     nForce MCP65                0446
  34     nForce MCP67                0542
  35     nForce MCP73                07D8
  36     nForce MCP78S               0752
  37     nForce MCP79                0AA2
  38
  39     This driver supports the 2 SMBuses that are included in the MCP of the
  40     nForce2/3/4/5xx chipsets.
  41 */
  42
  43 /* Note: we assume there can only be one nForce2, with two SMBus interfaces */
  44
  45 #include <linux/module.h>
  46 #include <linux/pci.h>
  47 #include <linux/kernel.h>
  48 #include <linux/stddef.h>
  49 #include <linux/ioport.h>
  50 #include <linux/i2c.h>
  51 #include <linux/delay.h>
  52 #include <linux/dmi.h>
  53 #include <linux/acpi.h>
  54 #include <linux/slab.h>
  55 #include <linux/io.h>
  56
  57 MODULE_LICENSE("GPL");
  58 MODULE_AUTHOR("Hans-Frieder Vogt <hfvogt@gmx.net>");
  59 MODULE_DESCRIPTION("nForce2/3/4/5xx SMBus driver");
  60
  61
  62 struct nforce2_smbus {
  63         struct i2c_adapter adapter;
  64         int base;
  65         int size;
  66         int blockops;
  67         int can_abort;
  68 };
  69
  70
  71 /*
  72  * nVidia nForce2 SMBus control register definitions
  73  * (Newer incarnations use standard BARs 4 and 5 instead)
  74  */
  75 #define NFORCE_PCI_SMB1 0x50
  76 #define NFORCE_PCI_SMB2 0x54
  77
  78
  79 /*
  80  * ACPI 2.0 chapter 13 SMBus 2.0 EC register model
  81  */
  82 #define NVIDIA_SMB_PRTCL        (smbus->base + 0x00)    /* protocol, PEC */
  83 #define NVIDIA_SMB_STS          (smbus->base + 0x01)    /* status */
  84 #define NVIDIA_SMB_ADDR         (smbus->base + 0x02)    /* address */
  85 #define NVIDIA_SMB_CMD          (smbus->base + 0x03)    /* command */
  86 #define NVIDIA_SMB_DATA         (smbus->base + 0x04)    /* 32 data registers */
  87 #define NVIDIA_SMB_BCNT         (smbus->base + 0x24)    /* number of data
  88                                                            bytes */
  89 #define NVIDIA_SMB_STATUS_ABRT  (smbus->base + 0x3c)    /* register used to
  90                                                            check the status of
  91                                                            the abort command */
  92 #define NVIDIA_SMB_CTRL         (smbus->base + 0x3e)    /* control register */
  93
  94 #define NVIDIA_SMB_STATUS_ABRT_STS      0x01            /* Bit to notify that
  95                                                            abort succeeded */
  96 #define NVIDIA_SMB_CTRL_ABORT   0x20
  97 #define NVIDIA_SMB_STS_DONE     0x80
  98 #define NVIDIA_SMB_STS_ALRM     0x40
  99 #define NVIDIA_SMB_STS_RES      0x20
 100 #define NVIDIA_SMB_STS_STATUS   0x1f
 101
 102 #define NVIDIA_SMB_PRTCL_WRITE                  0x00
 103 #define NVIDIA_SMB_PRTCL_READ                   0x01
 104 #define NVIDIA_SMB_PRTCL_QUICK                  0x02
 105 #define NVIDIA_SMB_PRTCL_BYTE                   0x04
 106 #define NVIDIA_SMB_PRTCL_BYTE_DATA              0x06
 107 #define NVIDIA_SMB_PRTCL_WORD_DATA              0x08
 108 #define NVIDIA_SMB_PRTCL_BLOCK_DATA             0x0a
 109 #define NVIDIA_SMB_PRTCL_PEC                    0x80
 110
 111 /* Misc definitions */
 112 #define MAX_TIMEOUT     100
 113
 114 /* We disable the second SMBus channel on these boards */
 115 static const struct dmi_system_id nforce2_dmi_blacklist2[] = {
 116         {
 117                 .ident = "DFI Lanparty NF4 Expert",
 118                 .matches = {
 119                         DMI_MATCH(DMI_BOARD_VENDOR, "DFI Corp,LTD"),
 120                         DMI_MATCH(DMI_BOARD_NAME, "LP UT NF4 Expert"),
 121                 },
 122         },
 123         { }
 124 };
 125
 126 static struct pci_driver nforce2_driver;
 127
 128 /* For multiplexing support, we need a global reference to the 1st
 129    SMBus channel */
 130 #if IS_ENABLED(CONFIG_I2C_NFORCE2_S4985)
 131 struct i2c_adapter *nforce2_smbus;
 132 EXPORT_SYMBOL_GPL(nforce2_smbus);
 133
 134 static void nforce2_set_reference(struct i2c_adapter *adap)
 135 {
 136         nforce2_smbus = adap;
 137 }
 138 #else
 139 static inline void nforce2_set_reference(struct i2c_adapter *adap) { }
 140 #endif
 141
 142 static void nforce2_abort(struct i2c_adapter *adap)
 143 {
 144         struct nforce2_smbus *smbus = adap->algo_data;
 145         int timeout = 0;
 146         unsigned char temp;
 147
 148         dev_dbg(&adap->dev, "Aborting current transaction\n");
 149
 150         outb_p(NVIDIA_SMB_CTRL_ABORT, NVIDIA_SMB_CTRL);
 151         do {
 152                 msleep(1);
 153                 temp = inb_p(NVIDIA_SMB_STATUS_ABRT);
 154         } while (!(temp & NVIDIA_SMB_STATUS_ABRT_STS) &&
 155                         (timeout++ < MAX_TIMEOUT));
 156         if (!(temp & NVIDIA_SMB_STATUS_ABRT_STS))
 157                 dev_err(&adap->dev, "Can't reset the smbus\n");
 158         outb_p(NVIDIA_SMB_STATUS_ABRT_STS, NVIDIA_SMB_STATUS_ABRT);
 159 }
 160
 161 static int nforce2_check_status(struct i2c_adapter *adap)
 162 {
 163         struct nforce2_smbus *smbus = adap->algo_data;
 164         int timeout = 0;
 165         unsigned char temp;
 166
 167         do {
 168                 msleep(1);
 169                 temp = inb_p(NVIDIA_SMB_STS);
 170         } while ((!temp) && (timeout++ < MAX_TIMEOUT));
 171
 172         if (timeout > MAX_TIMEOUT) {
 173                 dev_dbg(&adap->dev, "SMBus Timeout!\n");
 174                 if (smbus->can_abort)
 175                         nforce2_abort(adap);
 176                 return -ETIMEDOUT;
 177         }
 178         if (!(temp & NVIDIA_SMB_STS_DONE) || (temp & NVIDIA_SMB_STS_STATUS)) {
 179                 dev_dbg(&adap->dev, "Transaction failed (0x%02x)!\n", temp);
 180                 return -EIO;
 181         }
 182         return 0;
 183 }
 184
 185 /* Return negative errno on error */
 186 static s32 nforce2_access(struct i2c_adapter *adap, u16 addr,
 187                 unsigned short flags, char read_write,
 188                 u8 command, int size, union i2c_smbus_data *data)
 189 {
 190         struct nforce2_smbus *smbus = adap->algo_data;
 191         unsigned char protocol, pec;
 192         u8 len;
 193         int i, status;
 194
 195         protocol = (read_write == I2C_SMBUS_READ) ? NVIDIA_SMB_PRTCL_READ :
 196                 NVIDIA_SMB_PRTCL_WRITE;
 197         pec = (flags & I2C_CLIENT_PEC) ? NVIDIA_SMB_PRTCL_PEC : 0;
 198
 199         switch (size) {
 200         case I2C_SMBUS_QUICK:
 201                 protocol |= NVIDIA_SMB_PRTCL_QUICK;
 202                 read_write = I2C_SMBUS_WRITE;
 203                 break;
 204
 205         case I2C_SMBUS_BYTE:
 206                 if (read_write == I2C_SMBUS_WRITE)
 207                         outb_p(command, NVIDIA_SMB_CMD);
 208                 protocol |= NVIDIA_SMB_PRTCL_BYTE;
 209                 break;
 210
 211         case I2C_SMBUS_BYTE_DATA:
 212                 outb_p(command, NVIDIA_SMB_CMD);
 213                 if (read_write == I2C_SMBUS_WRITE)
 214                         outb_p(data->byte, NVIDIA_SMB_DATA);
 215                 protocol |= NVIDIA_SMB_PRTCL_BYTE_DATA;
 216                 break;
 217
 218         case I2C_SMBUS_WORD_DATA:
 219                 outb_p(command, NVIDIA_SMB_CMD);
 220                 if (read_write == I2C_SMBUS_WRITE) {
 221                         outb_p(data->word, NVIDIA_SMB_DATA);
 222                         outb_p(data->word >> 8, NVIDIA_SMB_DATA + 1);
 223                 }
 224                 protocol |= NVIDIA_SMB_PRTCL_WORD_DATA | pec;
 225                 break;
 226
 227         case I2C_SMBUS_BLOCK_DATA:
 228                 outb_p(command, NVIDIA_SMB_CMD);
 229                 if (read_write == I2C_SMBUS_WRITE) {
 230                         len = data->block[0];
 231                         if ((len == 0) || (len > I2C_SMBUS_BLOCK_MAX)) {
 232                                 dev_err(&adap->dev,
 233                                         "Transaction failed (requested block size: %d)\n",
 234                                         len);
 235                                 return -EINVAL;
 236                         }
 237                         outb_p(len, NVIDIA_SMB_BCNT);
 238                         for (i = 0; i < I2C_SMBUS_BLOCK_MAX; i++)
 239                                 outb_p(data->block[i + 1],
 240                                        NVIDIA_SMB_DATA + i);
 241                 }
 242                 protocol |= NVIDIA_SMB_PRTCL_BLOCK_DATA | pec;
 243                 break;
 244
 245         default:
 246                 dev_err(&adap->dev, "Unsupported transaction %d\n", size);
 247                 return -EOPNOTSUPP;
 248         }
 249
 250         outb_p((addr & 0x7f) << 1, NVIDIA_SMB_ADDR);
 251         outb_p(protocol, NVIDIA_SMB_PRTCL);
 252
 253         status = nforce2_check_status(adap);
 254         if (status)
 255                 return status;
 256
 257         if (read_write == I2C_SMBUS_WRITE)
 258                 return 0;
 259
 260         switch (size) {
 261         case I2C_SMBUS_BYTE:
 262         case I2C_SMBUS_BYTE_DATA:
 263                 data->byte = inb_p(NVIDIA_SMB_DATA);
 264                 break;
 265
 266         case I2C_SMBUS_WORD_DATA:
 267                 data->word = inb_p(NVIDIA_SMB_DATA) |
 268                              (inb_p(NVIDIA_SMB_DATA + 1) << 8);
 269                 break;
 270
 271         case I2C_SMBUS_BLOCK_DATA:
 272                 len = inb_p(NVIDIA_SMB_BCNT);
 273                 if ((len <= 0) || (len > I2C_SMBUS_BLOCK_MAX)) {
 274                         dev_err(&adap->dev,
 275                                 "Transaction failed (received block size: 0x%02x)\n",
 276                                 len);
 277                         return -EPROTO;
 278                 }
 279                 for (i = 0; i < len; i++)
 280                         data->block[i + 1] = inb_p(NVIDIA_SMB_DATA + i);
 281                 data->block[0] = len;
 282                 break;
 283         }
 284
 285         return 0;
 286 }
 287
 288
 289 static u32 nforce2_func(struct i2c_adapter *adapter)
 290 {
 291         /* other functionality might be possible, but is not tested */
 292         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
 293                I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
 294                I2C_FUNC_SMBUS_PEC |
 295                (((struct nforce2_smbus *)adapter->algo_data)->blockops ?
 296                 I2C_FUNC_SMBUS_BLOCK_DATA : 0);
 297 }
 298
 299 static const struct i2c_algorithm smbus_algorithm = {
 300         .smbus_xfer     = nforce2_access,
 301         .functionality  = nforce2_func,
 302 };
 303
 304
 305 static const struct pci_device_id nforce2_ids[] = {
 306         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE2_SMBUS) },
 307         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE2S_SMBUS) },
 308         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE3_SMBUS) },
 309         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE3S_SMBUS) },
 310         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE4_SMBUS) },
 311         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP04_SMBUS) },
 312         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SMBUS) },
 313         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SMBUS) },
 314         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP61_SMBUS) },
 315         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP65_SMBUS) },
 316         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP67_SMBUS) },
 317         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP73_SMBUS) },
 318         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP78S_SMBUS) },
 319         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP79_SMBUS) },
 320         { 0 }
 321 };
 322
 323 MODULE_DEVICE_TABLE(pci, nforce2_ids);
 324
 325
 326 static int nforce2_probe_smb(struct pci_dev *dev, int bar, int alt_reg,
 327                              struct nforce2_smbus *smbus, const char *name)
 328 {
 329         int error;
 330
 331         smbus->base = pci_resource_start(dev, bar);
 332         if (smbus->base) {
 333                 smbus->size = pci_resource_len(dev, bar);
 334         } else {
 335                 /* Older incarnations of the device used non-standard BARs */
 336                 u16 iobase;
 337
 338                 if (pci_read_config_word(dev, alt_reg, &iobase)
 339                     != PCIBIOS_SUCCESSFUL) {
 340                         dev_err(&dev->dev, "Error reading PCI config for %s\n",
 341                                 name);
 342                         return -EIO;
 343                 }
 344
 345                 smbus->base = iobase & PCI_BASE_ADDRESS_IO_MASK;
 346                 smbus->size = 64;
 347         }
 348
 349         error = acpi_check_region(smbus->base, smbus->size,
 350                                   nforce2_driver.name);
 351         if (error)
 352                 return error;
 353
 354         if (!request_region(smbus->base, smbus->size, nforce2_driver.name)) {
 355                 dev_err(&smbus->adapter.dev, "Error requesting region %02x .. %02X for %s\n",
 356                         smbus->base, smbus->base+smbus->size-1, name);
 357                 return -EBUSY;
 358         }
 359         smbus->adapter.owner = THIS_MODULE;
 360         smbus->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
 361         smbus->adapter.algo = &smbus_algorithm;
 362         smbus->adapter.algo_data = smbus;
 363         smbus->adapter.dev.parent = &dev->dev;
 364         snprintf(smbus->adapter.name, sizeof(smbus->adapter.name),
 365                 "SMBus nForce2 adapter at %04x", smbus->base);
 366
 367         error = i2c_add_adapter(&smbus->adapter);
 368         if (error) {
 369                 release_region(smbus->base, smbus->size);
 370                 return error;
 371         }
 372         dev_info(&smbus->adapter.dev, "nForce2 SMBus adapter at %#x\n",
 373                 smbus->base);
 374         return 0;
 375 }
 376
 377
 378 static int nforce2_probe(struct pci_dev *dev, const struct pci_device_id *id)
 379 {
 380         struct nforce2_smbus *smbuses;
 381         int res1, res2;
 382
 383         /* we support 2 SMBus adapters */
 384         smbuses = kcalloc(2, sizeof(struct nforce2_smbus), GFP_KERNEL);
 385         if (!smbuses)
 386                 return -ENOMEM;
 387         pci_set_drvdata(dev, smbuses);
 388
 389         switch (dev->device) {
 390         case PCI_DEVICE_ID_NVIDIA_NFORCE2_SMBUS:
 391         case PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SMBUS:
 392         case PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SMBUS:
 393                 smbuses[0].blockops = 1;
 394                 smbuses[1].blockops = 1;
 395                 smbuses[0].can_abort = 1;
 396                 smbuses[1].can_abort = 1;
 397         }
 398
 399         /* SMBus adapter 1 */
 400         res1 = nforce2_probe_smb(dev, 4, NFORCE_PCI_SMB1, &smbuses[0], "SMB1");
 401         if (res1 < 0)
 402                 smbuses[0].base = 0;    /* to have a check value */
 403
 404         /* SMBus adapter 2 */
 405         if (dmi_check_system(nforce2_dmi_blacklist2)) {
 406                 dev_err(&dev->dev, "Disabling SMB2 for safety reasons.\n");
 407                 res2 = -EPERM;
 408                 smbuses[1].base = 0;
 409         } else {
 410                 res2 = nforce2_probe_smb(dev, 5, NFORCE_PCI_SMB2, &smbuses[1],
 411                                          "SMB2");
 412                 if (res2 < 0)
 413                         smbuses[1].base = 0;    /* to have a check value */
 414         }
 415
 416         if ((res1 < 0) && (res2 < 0)) {
 417                 /* we did not find even one of the SMBuses, so we give up */
 418                 kfree(smbuses);
 419                 return -ENODEV;
 420         }
 421
 422         nforce2_set_reference(&smbuses[0].adapter);
 423         return 0;
 424 }
 425
 426
 427 static void nforce2_remove(struct pci_dev *dev)
 428 {
 429         struct nforce2_smbus *smbuses = pci_get_drvdata(dev);
 430
 431         nforce2_set_reference(NULL);
 432         if (smbuses[0].base) {
 433                 i2c_del_adapter(&smbuses[0].adapter);
 434                 release_region(smbuses[0].base, smbuses[0].size);
 435         }
 436         if (smbuses[1].base) {
 437                 i2c_del_adapter(&smbuses[1].adapter);
 438                 release_region(smbuses[1].base, smbuses[1].size);
 439         }
 440         kfree(smbuses);
 441 }
 442
 443 static struct pci_driver nforce2_driver = {
 444         .name           = "nForce2_smbus",
 445         .id_table       = nforce2_ids,
 446         .probe          = nforce2_probe,
 447         .remove         = nforce2_remove,
 448 };
 449
 450 module_pci_driver(nforce2_driver);