drivers/i2c/busses/i2c-xgene-slimpro.c

   1 /*
   2  * X-Gene SLIMpro I2C Driver
   3  *
   4  * Copyright (c) 2014, Applied Micro Circuits Corporation
   5  * Author: Feng Kan <fkan@apm.com>
   6  * Author: Hieu Le <hnle@apm.com>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  20  *
  21  * This driver provides support for X-Gene SLIMpro I2C device access
  22  * using the APM X-Gene SLIMpro mailbox driver.
  23  *
  24  */
  25 #include <acpi/pcc.h>
  26 #include <linux/acpi.h>
  27 #include <linux/dma-mapping.h>
  28 #include <linux/i2c.h>
  29 #include <linux/interrupt.h>
  30 #include <linux/io.h>
  31 #include <linux/mailbox_client.h>
  32 #include <linux/module.h>
  33 #include <linux/of.h>
  34 #include <linux/platform_device.h>
  35 #include <linux/version.h>
  36
  37 #define MAILBOX_OP_TIMEOUT              1000    /* Operation time out in ms */
  38 #define MAILBOX_I2C_INDEX               0
  39 #define SLIMPRO_IIC_BUS                 1       /* Use I2C bus 1 only */
  40
  41 #define SMBUS_CMD_LEN                   1
  42 #define BYTE_DATA                       1
  43 #define WORD_DATA                       2
  44 #define BLOCK_DATA                      3
  45
  46 #define SLIMPRO_IIC_I2C_PROTOCOL        0
  47 #define SLIMPRO_IIC_SMB_PROTOCOL        1
  48
  49 #define SLIMPRO_IIC_READ                0
  50 #define SLIMPRO_IIC_WRITE               1
  51
  52 #define IIC_SMB_WITHOUT_DATA_LEN        0
  53 #define IIC_SMB_WITH_DATA_LEN           1
  54
  55 #define SLIMPRO_DEBUG_MSG               0
  56 #define SLIMPRO_MSG_TYPE_SHIFT          28
  57 #define SLIMPRO_DBG_SUBTYPE_I2C1READ    4
  58 #define SLIMPRO_DBGMSG_TYPE_SHIFT       24
  59 #define SLIMPRO_DBGMSG_TYPE_MASK        0x0F000000U
  60 #define SLIMPRO_IIC_DEV_SHIFT           23
  61 #define SLIMPRO_IIC_DEV_MASK            0x00800000U
  62 #define SLIMPRO_IIC_DEVID_SHIFT         13
  63 #define SLIMPRO_IIC_DEVID_MASK          0x007FE000U
  64 #define SLIMPRO_IIC_RW_SHIFT            12
  65 #define SLIMPRO_IIC_RW_MASK             0x00001000U
  66 #define SLIMPRO_IIC_PROTO_SHIFT         11
  67 #define SLIMPRO_IIC_PROTO_MASK          0x00000800U
  68 #define SLIMPRO_IIC_ADDRLEN_SHIFT       8
  69 #define SLIMPRO_IIC_ADDRLEN_MASK        0x00000700U
  70 #define SLIMPRO_IIC_DATALEN_SHIFT       0
  71 #define SLIMPRO_IIC_DATALEN_MASK        0x000000FFU
  72
  73 /*
  74  * SLIMpro I2C message encode
  75  *
  76  * dev          - Controller number (0-based)
  77  * chip         - I2C chip address
  78  * op           - SLIMPRO_IIC_READ or SLIMPRO_IIC_WRITE
  79  * proto        - SLIMPRO_IIC_SMB_PROTOCOL or SLIMPRO_IIC_I2C_PROTOCOL
  80  * addrlen      - Length of the address field
  81  * datalen      - Length of the data field
  82  */
  83 #define SLIMPRO_IIC_ENCODE_MSG(dev, chip, op, proto, addrlen, datalen) \
  84         ((SLIMPRO_DEBUG_MSG << SLIMPRO_MSG_TYPE_SHIFT) | \
  85         ((SLIMPRO_DBG_SUBTYPE_I2C1READ << SLIMPRO_DBGMSG_TYPE_SHIFT) & \
  86         SLIMPRO_DBGMSG_TYPE_MASK) | \
  87         ((dev << SLIMPRO_IIC_DEV_SHIFT) & SLIMPRO_IIC_DEV_MASK) | \
  88         ((chip << SLIMPRO_IIC_DEVID_SHIFT) & SLIMPRO_IIC_DEVID_MASK) | \
  89         ((op << SLIMPRO_IIC_RW_SHIFT) & SLIMPRO_IIC_RW_MASK) | \
  90         ((proto << SLIMPRO_IIC_PROTO_SHIFT) & SLIMPRO_IIC_PROTO_MASK) | \
  91         ((addrlen << SLIMPRO_IIC_ADDRLEN_SHIFT) & SLIMPRO_IIC_ADDRLEN_MASK) | \
  92         ((datalen << SLIMPRO_IIC_DATALEN_SHIFT) & SLIMPRO_IIC_DATALEN_MASK))
  93
  94 #define SLIMPRO_MSG_TYPE(v)             (((v) & 0xF0000000) >> 28)
  95
  96 /*
  97  * Encode for upper address for block data
  98  */
  99 #define SLIMPRO_IIC_ENCODE_FLAG_BUFADDR                 0x80000000
 100 #define SLIMPRO_IIC_ENCODE_FLAG_WITH_DATA_LEN(a)        ((u32) (((a) << 30) \
 101                                                                 & 0x40000000))
 102 #define SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(a)             ((u32) (((a) >> 12) \
 103                                                                 & 0x3FF00000))
 104 #define SLIMPRO_IIC_ENCODE_ADDR(a)                      ((a) & 0x000FFFFF)
 105
 106 #define SLIMPRO_IIC_MSG_DWORD_COUNT                     3
 107
 108 /* PCC related defines */
 109 #define PCC_SIGNATURE                   0x50424300
 110 #define PCC_STS_CMD_COMPLETE            BIT(0)
 111 #define PCC_STS_SCI_DOORBELL            BIT(1)
 112 #define PCC_STS_ERR                     BIT(2)
 113 #define PCC_STS_PLAT_NOTIFY             BIT(3)
 114 #define PCC_CMD_GENERATE_DB_INT         BIT(15)
 115
 116 struct slimpro_i2c_dev {
 117         struct i2c_adapter adapter;
 118         struct device *dev;
 119         struct mbox_chan *mbox_chan;
 120         struct mbox_client mbox_client;
 121         int mbox_idx;
 122         struct completion rd_complete;
 123         u8 dma_buffer[I2C_SMBUS_BLOCK_MAX + 1]; /* dma_buffer[0] is used for length */
 124         u32 *resp_msg;
 125         phys_addr_t comm_base_addr;
 126         void *pcc_comm_addr;
 127 };
 128
 129 #define to_slimpro_i2c_dev(cl)  \
 130                 container_of(cl, struct slimpro_i2c_dev, mbox_client)
 131
 132 /*
 133  * This function tests and clears a bitmask then returns its old value
 134  */
 135 static u16 xgene_word_tst_and_clr(u16 *addr, u16 mask)
 136 {
 137         u16 ret, val;
 138
 139         val = le16_to_cpu(READ_ONCE(*addr));
 140         ret = val & mask;
 141         val &= ~mask;
 142         WRITE_ONCE(*addr, cpu_to_le16(val));
 143
 144         return ret;
 145 }
 146
 147 static void slimpro_i2c_rx_cb(struct mbox_client *cl, void *mssg)
 148 {
 149         struct slimpro_i2c_dev *ctx = to_slimpro_i2c_dev(cl);
 150
 151         /*
 152          * Response message format:
 153          * mssg[0] is the return code of the operation
 154          * mssg[1] is the first data word
 155          * mssg[2] is NOT used
 156          */
 157         if (ctx->resp_msg)
 158                 *ctx->resp_msg = ((u32 *)mssg)[1];
 159
 160         if (ctx->mbox_client.tx_block)
 161                 complete(&ctx->rd_complete);
 162 }
 163
 164 static void slimpro_i2c_pcc_rx_cb(struct mbox_client *cl, void *msg)
 165 {
 166         struct slimpro_i2c_dev *ctx = to_slimpro_i2c_dev(cl);
 167         struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
 168
 169         /* Check if platform sends interrupt */
 170         if (!xgene_word_tst_and_clr(&generic_comm_base->status,
 171                                     PCC_STS_SCI_DOORBELL))
 172                 return;
 173
 174         if (xgene_word_tst_and_clr(&generic_comm_base->status,
 175                                    PCC_STS_CMD_COMPLETE)) {
 176                 msg = generic_comm_base + 1;
 177
 178                 /* Response message msg[1] contains the return value. */
 179                 if (ctx->resp_msg)
 180                         *ctx->resp_msg = ((u32 *)msg)[1];
 181
 182                 complete(&ctx->rd_complete);
 183         }
 184 }
 185
 186 static void slimpro_i2c_pcc_tx_prepare(struct slimpro_i2c_dev *ctx, u32 *msg)
 187 {
 188         struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
 189         u32 *ptr = (void *)(generic_comm_base + 1);
 190         u16 status;
 191         int i;
 192
 193         WRITE_ONCE(generic_comm_base->signature,
 194                    cpu_to_le32(PCC_SIGNATURE | ctx->mbox_idx));
 195
 196         WRITE_ONCE(generic_comm_base->command,
 197                    cpu_to_le16(SLIMPRO_MSG_TYPE(msg[0]) | PCC_CMD_GENERATE_DB_INT));
 198
 199         status = le16_to_cpu(READ_ONCE(generic_comm_base->status));
 200         status &= ~PCC_STS_CMD_COMPLETE;
 201         WRITE_ONCE(generic_comm_base->status, cpu_to_le16(status));
 202
 203         /* Copy the message to the PCC comm space */
 204         for (i = 0; i < SLIMPRO_IIC_MSG_DWORD_COUNT; i++)
 205                 WRITE_ONCE(ptr[i], cpu_to_le32(msg[i]));
 206 }
 207
 208 static int start_i2c_msg_xfer(struct slimpro_i2c_dev *ctx)
 209 {
 210         if (ctx->mbox_client.tx_block || !acpi_disabled) {
 211                 if (!wait_for_completion_timeout(&ctx->rd_complete,
 212                                                  msecs_to_jiffies(MAILBOX_OP_TIMEOUT)))
 213                         return -ETIMEDOUT;
 214         }
 215
 216         /* Check of invalid data or no device */
 217         if (*ctx->resp_msg == 0xffffffff)
 218                 return -ENODEV;
 219
 220         return 0;
 221 }
 222
 223 static int slimpro_i2c_send_msg(struct slimpro_i2c_dev *ctx,
 224                                 u32 *msg,
 225                                 u32 *data)
 226 {
 227         int rc;
 228
 229         ctx->resp_msg = data;
 230
 231         if (!acpi_disabled) {
 232                 reinit_completion(&ctx->rd_complete);
 233                 slimpro_i2c_pcc_tx_prepare(ctx, msg);
 234         }
 235
 236         rc = mbox_send_message(ctx->mbox_chan, msg);
 237         if (rc < 0)
 238                 goto err;
 239
 240         rc = start_i2c_msg_xfer(ctx);
 241
 242 err:
 243         if (!acpi_disabled)
 244                 mbox_chan_txdone(ctx->mbox_chan, 0);
 245
 246         ctx->resp_msg = NULL;
 247
 248         return rc;
 249 }
 250
 251 static int slimpro_i2c_rd(struct slimpro_i2c_dev *ctx, u32 chip,
 252                           u32 addr, u32 addrlen, u32 protocol,
 253                           u32 readlen, u32 *data)
 254 {
 255         u32 msg[3];
 256
 257         msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip,
 258                                         SLIMPRO_IIC_READ, protocol, addrlen, readlen);
 259         msg[1] = SLIMPRO_IIC_ENCODE_ADDR(addr);
 260         msg[2] = 0;
 261
 262         return slimpro_i2c_send_msg(ctx, msg, data);
 263 }
 264
 265 static int slimpro_i2c_wr(struct slimpro_i2c_dev *ctx, u32 chip,
 266                           u32 addr, u32 addrlen, u32 protocol, u32 writelen,
 267                           u32 data)
 268 {
 269         u32 msg[3];
 270
 271         msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip,
 272                                         SLIMPRO_IIC_WRITE, protocol, addrlen, writelen);
 273         msg[1] = SLIMPRO_IIC_ENCODE_ADDR(addr);
 274         msg[2] = data;
 275
 276         return slimpro_i2c_send_msg(ctx, msg, msg);
 277 }
 278
 279 static int slimpro_i2c_blkrd(struct slimpro_i2c_dev *ctx, u32 chip, u32 addr,
 280                              u32 addrlen, u32 protocol, u32 readlen,
 281                              u32 with_data_len, void *data)
 282 {
 283         dma_addr_t paddr;
 284         u32 msg[3];
 285         int rc;
 286
 287         paddr = dma_map_single(ctx->dev, ctx->dma_buffer, readlen, DMA_FROM_DEVICE);
 288         if (dma_mapping_error(ctx->dev, paddr)) {
 289                 dev_err(&ctx->adapter.dev, "Error in mapping dma buffer %p\n",
 290                         ctx->dma_buffer);
 291                 return -ENOMEM;
 292         }
 293
 294         msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, SLIMPRO_IIC_READ,
 295                                         protocol, addrlen, readlen);
 296         msg[1] = SLIMPRO_IIC_ENCODE_FLAG_BUFADDR |
 297                  SLIMPRO_IIC_ENCODE_FLAG_WITH_DATA_LEN(with_data_len) |
 298                  SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(paddr) |
 299                  SLIMPRO_IIC_ENCODE_ADDR(addr);
 300         msg[2] = (u32)paddr;
 301
 302         rc = slimpro_i2c_send_msg(ctx, msg, msg);
 303
 304         /* Copy to destination */
 305         memcpy(data, ctx->dma_buffer, readlen);
 306
 307         dma_unmap_single(ctx->dev, paddr, readlen, DMA_FROM_DEVICE);
 308         return rc;
 309 }
 310
 311 static int slimpro_i2c_blkwr(struct slimpro_i2c_dev *ctx, u32 chip,
 312                              u32 addr, u32 addrlen, u32 protocol, u32 writelen,
 313                              void *data)
 314 {
 315         dma_addr_t paddr;
 316         u32 msg[3];
 317         int rc;
 318
 319         if (writelen > I2C_SMBUS_BLOCK_MAX)
 320                 return -EINVAL;
 321
 322         memcpy(ctx->dma_buffer, data, writelen);
 323         paddr = dma_map_single(ctx->dev, ctx->dma_buffer, writelen,
 324                                DMA_TO_DEVICE);
 325         if (dma_mapping_error(ctx->dev, paddr)) {
 326                 dev_err(&ctx->adapter.dev, "Error in mapping dma buffer %p\n",
 327                         ctx->dma_buffer);
 328                 return -ENOMEM;
 329         }
 330
 331         msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, SLIMPRO_IIC_WRITE,
 332                                         protocol, addrlen, writelen);
 333         msg[1] = SLIMPRO_IIC_ENCODE_FLAG_BUFADDR |
 334                  SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(paddr) |
 335                  SLIMPRO_IIC_ENCODE_ADDR(addr);
 336         msg[2] = (u32)paddr;
 337
 338         if (ctx->mbox_client.tx_block)
 339                 reinit_completion(&ctx->rd_complete);
 340
 341         rc = slimpro_i2c_send_msg(ctx, msg, msg);
 342
 343         dma_unmap_single(ctx->dev, paddr, writelen, DMA_TO_DEVICE);
 344         return rc;
 345 }
 346
 347 static int xgene_slimpro_i2c_xfer(struct i2c_adapter *adap, u16 addr,
 348                                   unsigned short flags, char read_write,
 349                                   u8 command, int size,
 350                                   union i2c_smbus_data *data)
 351 {
 352         struct slimpro_i2c_dev *ctx = i2c_get_adapdata(adap);
 353         int ret = -EOPNOTSUPP;
 354         u32 val;
 355
 356         switch (size) {
 357         case I2C_SMBUS_BYTE:
 358                 if (read_write == I2C_SMBUS_READ) {
 359                         ret = slimpro_i2c_rd(ctx, addr, 0, 0,
 360                                              SLIMPRO_IIC_SMB_PROTOCOL,
 361                                              BYTE_DATA, &val);
 362                         data->byte = val;
 363                 } else {
 364                         ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN,
 365                                              SLIMPRO_IIC_SMB_PROTOCOL,
 366                                              0, 0);
 367                 }
 368                 break;
 369         case I2C_SMBUS_BYTE_DATA:
 370                 if (read_write == I2C_SMBUS_READ) {
 371                         ret = slimpro_i2c_rd(ctx, addr, command, SMBUS_CMD_LEN,
 372                                              SLIMPRO_IIC_SMB_PROTOCOL,
 373                                              BYTE_DATA, &val);
 374                         data->byte = val;
 375                 } else {
 376                         val = data->byte;
 377                         ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN,
 378                                              SLIMPRO_IIC_SMB_PROTOCOL,
 379                                              BYTE_DATA, val);
 380                 }
 381                 break;
 382         case I2C_SMBUS_WORD_DATA:
 383                 if (read_write == I2C_SMBUS_READ) {
 384                         ret = slimpro_i2c_rd(ctx, addr, command, SMBUS_CMD_LEN,
 385                                              SLIMPRO_IIC_SMB_PROTOCOL,
 386                                              WORD_DATA, &val);
 387                         data->word = val;
 388                 } else {
 389                         val = data->word;
 390                         ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN,
 391                                              SLIMPRO_IIC_SMB_PROTOCOL,
 392                                              WORD_DATA, val);
 393                 }
 394                 break;
 395         case I2C_SMBUS_BLOCK_DATA:
 396                 if (read_write == I2C_SMBUS_READ) {
 397                         ret = slimpro_i2c_blkrd(ctx, addr, command,
 398                                                 SMBUS_CMD_LEN,
 399                                                 SLIMPRO_IIC_SMB_PROTOCOL,
 400                                                 I2C_SMBUS_BLOCK_MAX + 1,
 401                                                 IIC_SMB_WITH_DATA_LEN,
 402                                                 &data->block[0]);
 403
 404                 } else {
 405                         ret = slimpro_i2c_blkwr(ctx, addr, command,
 406                                                 SMBUS_CMD_LEN,
 407                                                 SLIMPRO_IIC_SMB_PROTOCOL,
 408                                                 data->block[0] + 1,
 409                                                 &data->block[0]);
 410                 }
 411                 break;
 412         case I2C_SMBUS_I2C_BLOCK_DATA:
 413                 if (read_write == I2C_SMBUS_READ) {
 414                         ret = slimpro_i2c_blkrd(ctx, addr,
 415                                                 command,
 416                                                 SMBUS_CMD_LEN,
 417                                                 SLIMPRO_IIC_I2C_PROTOCOL,
 418                                                 I2C_SMBUS_BLOCK_MAX,
 419                                                 IIC_SMB_WITHOUT_DATA_LEN,
 420                                                 &data->block[1]);
 421                 } else {
 422                         ret = slimpro_i2c_blkwr(ctx, addr, command,
 423                                                 SMBUS_CMD_LEN,
 424                                                 SLIMPRO_IIC_I2C_PROTOCOL,
 425                                                 data->block[0],
 426                                                 &data->block[1]);
 427                 }
 428                 break;
 429         default:
 430                 break;
 431         }
 432         return ret;
 433 }
 434
 435 /*
 436 * Return list of supported functionality.
 437 */
 438 static u32 xgene_slimpro_i2c_func(struct i2c_adapter *adapter)
 439 {
 440         return I2C_FUNC_SMBUS_BYTE |
 441                 I2C_FUNC_SMBUS_BYTE_DATA |
 442                 I2C_FUNC_SMBUS_WORD_DATA |
 443                 I2C_FUNC_SMBUS_BLOCK_DATA |
 444                 I2C_FUNC_SMBUS_I2C_BLOCK;
 445 }
 446
 447 static const struct i2c_algorithm xgene_slimpro_i2c_algorithm = {
 448         .smbus_xfer = xgene_slimpro_i2c_xfer,
 449         .functionality = xgene_slimpro_i2c_func,
 450 };
 451
 452 static int xgene_slimpro_i2c_probe(struct platform_device *pdev)
 453 {
 454         struct slimpro_i2c_dev *ctx;
 455         struct i2c_adapter *adapter;
 456         struct mbox_client *cl;
 457         int rc;
 458
 459         ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
 460         if (!ctx)
 461                 return -ENOMEM;
 462
 463         ctx->dev = &pdev->dev;
 464         platform_set_drvdata(pdev, ctx);
 465         cl = &ctx->mbox_client;
 466
 467         /* Request mailbox channel */
 468         cl->dev = &pdev->dev;
 469         init_completion(&ctx->rd_complete);
 470         cl->tx_tout = MAILBOX_OP_TIMEOUT;
 471         cl->knows_txdone = false;
 472         if (acpi_disabled) {
 473                 cl->tx_block = true;
 474                 cl->rx_callback = slimpro_i2c_rx_cb;
 475                 ctx->mbox_chan = mbox_request_channel(cl, MAILBOX_I2C_INDEX);
 476                 if (IS_ERR(ctx->mbox_chan)) {
 477                         dev_err(&pdev->dev, "i2c mailbox channel request failed\n");
 478                         return PTR_ERR(ctx->mbox_chan);
 479                 }
 480         } else {
 481                 struct acpi_pcct_hw_reduced *cppc_ss;
 482
 483                 if (device_property_read_u32(&pdev->dev, "pcc-channel",
 484                                              &ctx->mbox_idx))
 485                         ctx->mbox_idx = MAILBOX_I2C_INDEX;
 486
 487                 cl->tx_block = false;
 488                 cl->rx_callback = slimpro_i2c_pcc_rx_cb;
 489                 ctx->mbox_chan = pcc_mbox_request_channel(cl, ctx->mbox_idx);
 490                 if (IS_ERR(ctx->mbox_chan)) {
 491                         dev_err(&pdev->dev, "PCC mailbox channel request failed\n");
 492                         return PTR_ERR(ctx->mbox_chan);
 493                 }
 494
 495                 /*
 496                  * The PCC mailbox controller driver should
 497                  * have parsed the PCCT (global table of all
 498                  * PCC channels) and stored pointers to the
 499                  * subspace communication region in con_priv.
 500                  */
 501                 cppc_ss = ctx->mbox_chan->con_priv;
 502                 if (!cppc_ss) {
 503                         dev_err(&pdev->dev, "PPC subspace not found\n");
 504                         rc = -ENOENT;
 505                         goto mbox_err;
 506                 }
 507
 508                 if (!ctx->mbox_chan->mbox->txdone_irq) {
 509                         dev_err(&pdev->dev, "PCC IRQ not supported\n");
 510                         rc = -ENOENT;
 511                         goto mbox_err;
 512                 }
 513
 514                 /*
 515                  * This is the shared communication region
 516                  * for the OS and Platform to communicate over.
 517                  */
 518                 ctx->comm_base_addr = cppc_ss->base_address;
 519                 if (ctx->comm_base_addr) {
 520                         ctx->pcc_comm_addr = memremap(ctx->comm_base_addr,
 521                                                       cppc_ss->length,
 522                                                       MEMREMAP_WB);
 523                 } else {
 524                         dev_err(&pdev->dev, "Failed to get PCC comm region\n");
 525                         rc = -ENOENT;
 526                         goto mbox_err;
 527                 }
 528
 529                 if (!ctx->pcc_comm_addr) {
 530                         dev_err(&pdev->dev,
 531                                 "Failed to ioremap PCC comm region\n");
 532                         rc = -ENOMEM;
 533                         goto mbox_err;
 534                 }
 535         }
 536         rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
 537         if (rc)
 538                 dev_warn(&pdev->dev, "Unable to set dma mask\n");
 539
 540         /* Setup I2C adapter */
 541         adapter = &ctx->adapter;
 542         snprintf(adapter->name, sizeof(adapter->name), "MAILBOX I2C");
 543         adapter->algo = &xgene_slimpro_i2c_algorithm;
 544         adapter->class = I2C_CLASS_HWMON;
 545         adapter->dev.parent = &pdev->dev;
 546         adapter->dev.of_node = pdev->dev.of_node;
 547         ACPI_COMPANION_SET(&adapter->dev, ACPI_COMPANION(&pdev->dev));
 548         i2c_set_adapdata(adapter, ctx);
 549         rc = i2c_add_adapter(adapter);
 550         if (rc)
 551                 goto mbox_err;
 552
 553         dev_info(&pdev->dev, "Mailbox I2C Adapter registered\n");
 554         return 0;
 555
 556 mbox_err:
 557         if (acpi_disabled)
 558                 mbox_free_channel(ctx->mbox_chan);
 559         else
 560                 pcc_mbox_free_channel(ctx->mbox_chan);
 561
 562         return rc;
 563 }
 564
 565 static int xgene_slimpro_i2c_remove(struct platform_device *pdev)
 566 {
 567         struct slimpro_i2c_dev *ctx = platform_get_drvdata(pdev);
 568
 569         i2c_del_adapter(&ctx->adapter);
 570
 571         if (acpi_disabled)
 572                 mbox_free_channel(ctx->mbox_chan);
 573         else
 574                 pcc_mbox_free_channel(ctx->mbox_chan);
 575
 576         return 0;
 577 }
 578
 579 static const struct of_device_id xgene_slimpro_i2c_dt_ids[] = {
 580         {.compatible = "apm,xgene-slimpro-i2c" },
 581         {},
 582 };
 583 MODULE_DEVICE_TABLE(of, xgene_slimpro_i2c_dt_ids);
 584
 585 #ifdef CONFIG_ACPI
 586 static const struct acpi_device_id xgene_slimpro_i2c_acpi_ids[] = {
 587         {"APMC0D40", 0},
 588         {}
 589 };
 590 MODULE_DEVICE_TABLE(acpi, xgene_slimpro_i2c_acpi_ids);
 591 #endif
 592
 593 static struct platform_driver xgene_slimpro_i2c_driver = {
 594         .probe  = xgene_slimpro_i2c_probe,
 595         .remove = xgene_slimpro_i2c_remove,
 596         .driver = {
 597                 .name   = "xgene-slimpro-i2c",
 598                 .of_match_table = of_match_ptr(xgene_slimpro_i2c_dt_ids),
 599                 .acpi_match_table = ACPI_PTR(xgene_slimpro_i2c_acpi_ids)
 600         },
 601 };
 602
 603 module_platform_driver(xgene_slimpro_i2c_driver);
 604
 605 MODULE_DESCRIPTION("APM X-Gene SLIMpro I2C driver");
 606 MODULE_AUTHOR("Feng Kan <fkan@apm.com>");
 607 MODULE_AUTHOR("Hieu Le <hnle@apm.com>");
 608 MODULE_LICENSE("GPL");