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