drivers/fsi/fsi-master-aspeed.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 // Copyright (C) IBM Corporation 2018
   3 // FSI master driver for AST2600
   4
   5 #include <linux/clk.h>
   6 #include <linux/delay.h>
   7 #include <linux/fsi.h>
   8 #include <linux/io.h>
   9 #include <linux/mfd/syscon.h>
  10 #include <linux/module.h>
  11 #include <linux/of.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/regmap.h>
  14 #include <linux/slab.h>
  15 #include <linux/iopoll.h>
  16 #include <linux/gpio/consumer.h>
  17
  18 #include "fsi-master.h"
  19
  20 struct fsi_master_aspeed {
  21         struct fsi_master       master;
  22         struct device           *dev;
  23         void __iomem            *base;
  24         struct clk              *clk;
  25         struct gpio_desc        *cfam_reset_gpio;
  26 };
  27
  28 #define to_fsi_master_aspeed(m) \
  29         container_of(m, struct fsi_master_aspeed, master)
  30
  31 /* Control register (size 0x400) */
  32 static const u32 ctrl_base = 0x80000000;
  33
  34 static const u32 fsi_base = 0xa0000000;
  35
  36 #define OPB_FSI_VER     0x00
  37 #define OPB_TRIGGER     0x04
  38 #define OPB_CTRL_BASE   0x08
  39 #define OPB_FSI_BASE    0x0c
  40 #define OPB_CLK_SYNC    0x3c
  41 #define OPB_IRQ_CLEAR   0x40
  42 #define OPB_IRQ_MASK    0x44
  43 #define OPB_IRQ_STATUS  0x48
  44
  45 #define OPB0_SELECT     0x10
  46 #define OPB0_RW         0x14
  47 #define OPB0_XFER_SIZE  0x18
  48 #define OPB0_FSI_ADDR   0x1c
  49 #define OPB0_FSI_DATA_W 0x20
  50 #define OPB0_STATUS     0x80
  51 #define OPB0_FSI_DATA_R 0x84
  52
  53 #define OPB0_WRITE_ORDER1       0x4c
  54 #define OPB0_WRITE_ORDER2       0x50
  55 #define OPB1_WRITE_ORDER1       0x54
  56 #define OPB1_WRITE_ORDER2       0x58
  57 #define OPB0_READ_ORDER1        0x5c
  58 #define OPB1_READ_ORDER2        0x60
  59
  60 #define OPB_RETRY_COUNTER       0x64
  61
  62 /* OPBn_STATUS */
  63 #define STATUS_HALFWORD_ACK     BIT(0)
  64 #define STATUS_FULLWORD_ACK     BIT(1)
  65 #define STATUS_ERR_ACK          BIT(2)
  66 #define STATUS_RETRY            BIT(3)
  67 #define STATUS_TIMEOUT          BIT(4)
  68
  69 /* OPB_IRQ_MASK */
  70 #define OPB1_XFER_ACK_EN BIT(17)
  71 #define OPB0_XFER_ACK_EN BIT(16)
  72
  73 /* OPB_RW */
  74 #define CMD_READ        BIT(0)
  75 #define CMD_WRITE       0
  76
  77 /* OPBx_XFER_SIZE */
  78 #define XFER_FULLWORD   (BIT(1) | BIT(0))
  79 #define XFER_HALFWORD   (BIT(0))
  80 #define XFER_BYTE       (0)
  81
  82 #define CREATE_TRACE_POINTS
  83 #include <trace/events/fsi_master_aspeed.h>
  84
  85 #define FSI_LINK_ENABLE_SETUP_TIME      10      /* in mS */
  86
  87 /* Run the bus at maximum speed by default */
  88 #define FSI_DIVISOR_DEFAULT            1
  89 #define FSI_DIVISOR_CABLED             2
  90 static u16 aspeed_fsi_divisor = FSI_DIVISOR_DEFAULT;
  91 module_param_named(bus_div,aspeed_fsi_divisor, ushort, 0);
  92
  93 #define OPB_POLL_TIMEOUT                10000
  94
  95 static int __opb_write(struct fsi_master_aspeed *aspeed, u32 addr,
  96                        u32 val, u32 transfer_size)
  97 {
  98         void __iomem *base = aspeed->base;
  99         u32 reg, status;
 100         int ret;
 101
 102         writel(CMD_WRITE, base + OPB0_RW);
 103         writel(transfer_size, base + OPB0_XFER_SIZE);
 104         writel(addr, base + OPB0_FSI_ADDR);
 105         writel(val, base + OPB0_FSI_DATA_W);
 106         writel(0x1, base + OPB_IRQ_CLEAR);
 107         writel(0x1, base + OPB_TRIGGER);
 108
 109         ret = readl_poll_timeout(base + OPB_IRQ_STATUS, reg,
 110                                 (reg & OPB0_XFER_ACK_EN) != 0,
 111                                 0, OPB_POLL_TIMEOUT);
 112
 113         status = readl(base + OPB0_STATUS);
 114
 115         trace_fsi_master_aspeed_opb_write(addr, val, transfer_size, status, reg);
 116
 117         /* Return error when poll timed out */
 118         if (ret)
 119                 return ret;
 120
 121         /* Command failed, master will reset */
 122         if (status & STATUS_ERR_ACK)
 123                 return -EIO;
 124
 125         return 0;
 126 }
 127
 128 static int opb_writeb(struct fsi_master_aspeed *aspeed, u32 addr, u8 val)
 129 {
 130         return __opb_write(aspeed, addr, val, XFER_BYTE);
 131 }
 132
 133 static int opb_writew(struct fsi_master_aspeed *aspeed, u32 addr, __be16 val)
 134 {
 135         return __opb_write(aspeed, addr, (__force u16)val, XFER_HALFWORD);
 136 }
 137
 138 static int opb_writel(struct fsi_master_aspeed *aspeed, u32 addr, __be32 val)
 139 {
 140         return __opb_write(aspeed, addr, (__force u32)val, XFER_FULLWORD);
 141 }
 142
 143 static int __opb_read(struct fsi_master_aspeed *aspeed, uint32_t addr,
 144                       u32 transfer_size, void *out)
 145 {
 146         void __iomem *base = aspeed->base;
 147         u32 result, reg;
 148         int status, ret;
 149
 150         writel(CMD_READ, base + OPB0_RW);
 151         writel(transfer_size, base + OPB0_XFER_SIZE);
 152         writel(addr, base + OPB0_FSI_ADDR);
 153         writel(0x1, base + OPB_IRQ_CLEAR);
 154         writel(0x1, base + OPB_TRIGGER);
 155
 156         ret = readl_poll_timeout(base + OPB_IRQ_STATUS, reg,
 157                            (reg & OPB0_XFER_ACK_EN) != 0,
 158                            0, OPB_POLL_TIMEOUT);
 159
 160         status = readl(base + OPB0_STATUS);
 161
 162         result = readl(base + OPB0_FSI_DATA_R);
 163
 164         trace_fsi_master_aspeed_opb_read(addr, transfer_size, result,
 165                         readl(base + OPB0_STATUS),
 166                         reg);
 167
 168         /* Return error when poll timed out */
 169         if (ret)
 170                 return ret;
 171
 172         /* Command failed, master will reset */
 173         if (status & STATUS_ERR_ACK)
 174                 return -EIO;
 175
 176         if (out) {
 177                 switch (transfer_size) {
 178                 case XFER_BYTE:
 179                         *(u8 *)out = result;
 180                         break;
 181                 case XFER_HALFWORD:
 182                         *(u16 *)out = result;
 183                         break;
 184                 case XFER_FULLWORD:
 185                         *(u32 *)out = result;
 186                         break;
 187                 default:
 188                         return -EINVAL;
 189                 }
 190
 191         }
 192
 193         return 0;
 194 }
 195
 196 static int opb_readl(struct fsi_master_aspeed *aspeed, uint32_t addr, __be32 *out)
 197 {
 198         return __opb_read(aspeed, addr, XFER_FULLWORD, out);
 199 }
 200
 201 static int opb_readw(struct fsi_master_aspeed *aspeed, uint32_t addr, __be16 *out)
 202 {
 203         return __opb_read(aspeed, addr, XFER_HALFWORD, (void *)out);
 204 }
 205
 206 static int opb_readb(struct fsi_master_aspeed *aspeed, uint32_t addr, u8 *out)
 207 {
 208         return __opb_read(aspeed, addr, XFER_BYTE, (void *)out);
 209 }
 210
 211 static int check_errors(struct fsi_master_aspeed *aspeed, int err)
 212 {
 213         int ret;
 214
 215         if (trace_fsi_master_aspeed_opb_error_enabled()) {
 216                 __be32 mresp0, mstap0, mesrb0;
 217
 218                 opb_readl(aspeed, ctrl_base + FSI_MRESP0, &mresp0);
 219                 opb_readl(aspeed, ctrl_base + FSI_MSTAP0, &mstap0);
 220                 opb_readl(aspeed, ctrl_base + FSI_MESRB0, &mesrb0);
 221
 222                 trace_fsi_master_aspeed_opb_error(
 223                                 be32_to_cpu(mresp0),
 224                                 be32_to_cpu(mstap0),
 225                                 be32_to_cpu(mesrb0));
 226         }
 227
 228         if (err == -EIO) {
 229                 /* Check MAEB (0x70) ? */
 230
 231                 /* Then clear errors in master */
 232                 ret = opb_writel(aspeed, ctrl_base + FSI_MRESP0,
 233                                 cpu_to_be32(FSI_MRESP_RST_ALL_MASTER));
 234                 if (ret) {
 235                         /* TODO: log? return different code? */
 236                         return ret;
 237                 }
 238                 /* TODO: confirm that 0x70 was okay */
 239         }
 240
 241         /* This will pass through timeout errors */
 242         return err;
 243 }
 244
 245 static int aspeed_master_read(struct fsi_master *master, int link,
 246                         uint8_t id, uint32_t addr, void *val, size_t size)
 247 {
 248         struct fsi_master_aspeed *aspeed = to_fsi_master_aspeed(master);
 249         int ret;
 250
 251         if (id > 0x3)
 252                 return -EINVAL;
 253
 254         addr |= id << 21;
 255         addr += link * FSI_HUB_LINK_SIZE;
 256
 257         switch (size) {
 258         case 1:
 259                 ret = opb_readb(aspeed, fsi_base + addr, val);
 260                 break;
 261         case 2:
 262                 ret = opb_readw(aspeed, fsi_base + addr, val);
 263                 break;
 264         case 4:
 265                 ret = opb_readl(aspeed, fsi_base + addr, val);
 266                 break;
 267         default:
 268                 return -EINVAL;
 269         }
 270
 271         ret = check_errors(aspeed, ret);
 272         if (ret)
 273                 return ret;
 274
 275         return 0;
 276 }
 277
 278 static int aspeed_master_write(struct fsi_master *master, int link,
 279                         uint8_t id, uint32_t addr, const void *val, size_t size)
 280 {
 281         struct fsi_master_aspeed *aspeed = to_fsi_master_aspeed(master);
 282         int ret;
 283
 284         if (id > 0x3)
 285                 return -EINVAL;
 286
 287         addr |= id << 21;
 288         addr += link * FSI_HUB_LINK_SIZE;
 289
 290         switch (size) {
 291         case 1:
 292                 ret = opb_writeb(aspeed, fsi_base + addr, *(u8 *)val);
 293                 break;
 294         case 2:
 295                 ret = opb_writew(aspeed, fsi_base + addr, *(__be16 *)val);
 296                 break;
 297         case 4:
 298                 ret = opb_writel(aspeed, fsi_base + addr, *(__be32 *)val);
 299                 break;
 300         default:
 301                 return -EINVAL;
 302         }
 303
 304         ret = check_errors(aspeed, ret);
 305         if (ret)
 306                 return ret;
 307
 308         return 0;
 309 }
 310
 311 static int aspeed_master_link_enable(struct fsi_master *master, int link,
 312                                      bool enable)
 313 {
 314         struct fsi_master_aspeed *aspeed = to_fsi_master_aspeed(master);
 315         int idx, bit, ret;
 316         __be32 reg;
 317
 318         idx = link / 32;
 319         bit = link % 32;
 320
 321         reg = cpu_to_be32(0x80000000 >> bit);
 322
 323         if (!enable)
 324                 return opb_writel(aspeed, ctrl_base + FSI_MCENP0 + (4 * idx),
 325                                   reg);
 326
 327         ret = opb_writel(aspeed, ctrl_base + FSI_MSENP0 + (4 * idx), reg);
 328         if (ret)
 329                 return ret;
 330
 331         mdelay(FSI_LINK_ENABLE_SETUP_TIME);
 332
 333         return 0;
 334 }
 335
 336 static int aspeed_master_term(struct fsi_master *master, int link, uint8_t id)
 337 {
 338         uint32_t addr;
 339         __be32 cmd;
 340
 341         addr = 0x4;
 342         cmd = cpu_to_be32(0xecc00000);
 343
 344         return aspeed_master_write(master, link, id, addr, &cmd, 4);
 345 }
 346
 347 static int aspeed_master_break(struct fsi_master *master, int link)
 348 {
 349         uint32_t addr;
 350         __be32 cmd;
 351
 352         addr = 0x0;
 353         cmd = cpu_to_be32(0xc0de0000);
 354
 355         return aspeed_master_write(master, link, 0, addr, &cmd, 4);
 356 }
 357
 358 static void aspeed_master_release(struct device *dev)
 359 {
 360         struct fsi_master_aspeed *aspeed =
 361                 to_fsi_master_aspeed(dev_to_fsi_master(dev));
 362
 363         kfree(aspeed);
 364 }
 365
 366 /* mmode encoders */
 367 static inline u32 fsi_mmode_crs0(u32 x)
 368 {
 369         return (x & FSI_MMODE_CRS0MASK) << FSI_MMODE_CRS0SHFT;
 370 }
 371
 372 static inline u32 fsi_mmode_crs1(u32 x)
 373 {
 374         return (x & FSI_MMODE_CRS1MASK) << FSI_MMODE_CRS1SHFT;
 375 }
 376
 377 static int aspeed_master_init(struct fsi_master_aspeed *aspeed)
 378 {
 379         __be32 reg;
 380
 381         reg = cpu_to_be32(FSI_MRESP_RST_ALL_MASTER | FSI_MRESP_RST_ALL_LINK
 382                         | FSI_MRESP_RST_MCR | FSI_MRESP_RST_PYE);
 383         opb_writel(aspeed, ctrl_base + FSI_MRESP0, reg);
 384
 385         /* Initialize the MFSI (hub master) engine */
 386         reg = cpu_to_be32(FSI_MRESP_RST_ALL_MASTER | FSI_MRESP_RST_ALL_LINK
 387                         | FSI_MRESP_RST_MCR | FSI_MRESP_RST_PYE);
 388         opb_writel(aspeed, ctrl_base + FSI_MRESP0, reg);
 389
 390         reg = cpu_to_be32(FSI_MECTRL_EOAE | FSI_MECTRL_P8_AUTO_TERM);
 391         opb_writel(aspeed, ctrl_base + FSI_MECTRL, reg);
 392
 393         reg = cpu_to_be32(FSI_MMODE_ECRC | FSI_MMODE_EPC | FSI_MMODE_RELA
 394                         | fsi_mmode_crs0(aspeed_fsi_divisor)
 395                         | fsi_mmode_crs1(aspeed_fsi_divisor)
 396                         | FSI_MMODE_P8_TO_LSB);
 397         dev_info(aspeed->dev, "mmode set to %08x (divisor %d)\n",
 398                         be32_to_cpu(reg), aspeed_fsi_divisor);
 399         opb_writel(aspeed, ctrl_base + FSI_MMODE, reg);
 400
 401         reg = cpu_to_be32(0xffff0000);
 402         opb_writel(aspeed, ctrl_base + FSI_MDLYR, reg);
 403
 404         reg = cpu_to_be32(~0);
 405         opb_writel(aspeed, ctrl_base + FSI_MSENP0, reg);
 406
 407         /* Leave enabled long enough for master logic to set up */
 408         mdelay(FSI_LINK_ENABLE_SETUP_TIME);
 409
 410         opb_writel(aspeed, ctrl_base + FSI_MCENP0, reg);
 411
 412         opb_readl(aspeed, ctrl_base + FSI_MAEB, NULL);
 413
 414         reg = cpu_to_be32(FSI_MRESP_RST_ALL_MASTER | FSI_MRESP_RST_ALL_LINK);
 415         opb_writel(aspeed, ctrl_base + FSI_MRESP0, reg);
 416
 417         opb_readl(aspeed, ctrl_base + FSI_MLEVP0, NULL);
 418
 419         /* Reset the master bridge */
 420         reg = cpu_to_be32(FSI_MRESB_RST_GEN);
 421         opb_writel(aspeed, ctrl_base + FSI_MRESB0, reg);
 422
 423         reg = cpu_to_be32(FSI_MRESB_RST_ERR);
 424         opb_writel(aspeed, ctrl_base + FSI_MRESB0, reg);
 425
 426         return 0;
 427 }
 428
 429 static ssize_t cfam_reset_store(struct device *dev, struct device_attribute *attr,
 430                                 const char *buf, size_t count)
 431 {
 432         struct fsi_master_aspeed *aspeed = dev_get_drvdata(dev);
 433
 434         gpiod_set_value(aspeed->cfam_reset_gpio, 1);
 435         usleep_range(900, 1000);
 436         gpiod_set_value(aspeed->cfam_reset_gpio, 0);
 437
 438         return count;
 439 }
 440
 441 static DEVICE_ATTR(cfam_reset, 0200, NULL, cfam_reset_store);
 442
 443 static int setup_cfam_reset(struct fsi_master_aspeed *aspeed)
 444 {
 445         struct device *dev = aspeed->dev;
 446         struct gpio_desc *gpio;
 447         int rc;
 448
 449         gpio = devm_gpiod_get_optional(dev, "cfam-reset", GPIOD_OUT_LOW);
 450         if (IS_ERR(gpio))
 451                 return PTR_ERR(gpio);
 452         if (!gpio)
 453                 return 0;
 454
 455         aspeed->cfam_reset_gpio = gpio;
 456
 457         rc = device_create_file(dev, &dev_attr_cfam_reset);
 458         if (rc) {
 459                 devm_gpiod_put(dev, gpio);
 460                 return rc;
 461         }
 462
 463         return 0;
 464 }
 465
 466 static int tacoma_cabled_fsi_fixup(struct device *dev)
 467 {
 468         struct gpio_desc *routing_gpio, *mux_gpio;
 469         int gpio;
 470
 471         /*
 472          * The routing GPIO is a jumper indicating we should mux for the
 473          * externally connected FSI cable.
 474          */
 475         routing_gpio = devm_gpiod_get_optional(dev, "fsi-routing",
 476                         GPIOD_IN | GPIOD_FLAGS_BIT_NONEXCLUSIVE);
 477         if (IS_ERR(routing_gpio))
 478                 return PTR_ERR(routing_gpio);
 479         if (!routing_gpio)
 480                 return 0;
 481
 482         mux_gpio = devm_gpiod_get_optional(dev, "fsi-mux", GPIOD_ASIS);
 483         if (IS_ERR(mux_gpio))
 484                 return PTR_ERR(mux_gpio);
 485         if (!mux_gpio)
 486                 return 0;
 487
 488         gpio = gpiod_get_value(routing_gpio);
 489         if (gpio < 0)
 490                 return gpio;
 491
 492         /* If the routing GPIO is high we should set the mux to low. */
 493         if (gpio) {
 494                 /*
 495                  * Cable signal integrity means we should run the bus
 496                  * slightly slower. Do not override if a kernel param
 497                  * has already overridden.
 498                  */
 499                 if (aspeed_fsi_divisor == FSI_DIVISOR_DEFAULT)
 500                         aspeed_fsi_divisor = FSI_DIVISOR_CABLED;
 501
 502                 gpiod_direction_output(mux_gpio, 0);
 503                 dev_info(dev, "FSI configured for external cable\n");
 504         } else {
 505                 gpiod_direction_output(mux_gpio, 1);
 506         }
 507
 508         devm_gpiod_put(dev, routing_gpio);
 509
 510         return 0;
 511 }
 512
 513 static int fsi_master_aspeed_probe(struct platform_device *pdev)
 514 {
 515         struct fsi_master_aspeed *aspeed;
 516         struct resource *res;
 517         int rc, links, reg;
 518         __be32 raw;
 519
 520         rc = tacoma_cabled_fsi_fixup(&pdev->dev);
 521         if (rc) {
 522                 dev_err(&pdev->dev, "Tacoma FSI cable fixup failed\n");
 523                 return rc;
 524         }
 525
 526         aspeed = devm_kzalloc(&pdev->dev, sizeof(*aspeed), GFP_KERNEL);
 527         if (!aspeed)
 528                 return -ENOMEM;
 529
 530         aspeed->dev = &pdev->dev;
 531
 532         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 533         aspeed->base = devm_ioremap_resource(&pdev->dev, res);
 534         if (IS_ERR(aspeed->base))
 535                 return PTR_ERR(aspeed->base);
 536
 537         aspeed->clk = devm_clk_get(aspeed->dev, NULL);
 538         if (IS_ERR(aspeed->clk)) {
 539                 dev_err(aspeed->dev, "couldn't get clock\n");
 540                 return PTR_ERR(aspeed->clk);
 541         }
 542         rc = clk_prepare_enable(aspeed->clk);
 543         if (rc) {
 544                 dev_err(aspeed->dev, "couldn't enable clock\n");
 545                 return rc;
 546         }
 547
 548         rc = setup_cfam_reset(aspeed);
 549         if (rc) {
 550                 dev_err(&pdev->dev, "CFAM reset GPIO setup failed\n");
 551         }
 552
 553         writel(0x1, aspeed->base + OPB_CLK_SYNC);
 554         writel(OPB1_XFER_ACK_EN | OPB0_XFER_ACK_EN,
 555                         aspeed->base + OPB_IRQ_MASK);
 556
 557         /* TODO: determine an appropriate value */
 558         writel(0x10, aspeed->base + OPB_RETRY_COUNTER);
 559
 560         writel(ctrl_base, aspeed->base + OPB_CTRL_BASE);
 561         writel(fsi_base, aspeed->base + OPB_FSI_BASE);
 562
 563         /* Set read data order */
 564         writel(0x00030b1b, aspeed->base + OPB0_READ_ORDER1);
 565
 566         /* Set write data order */
 567         writel(0x0011101b, aspeed->base + OPB0_WRITE_ORDER1);
 568         writel(0x0c330f3f, aspeed->base + OPB0_WRITE_ORDER2);
 569
 570         /*
 571          * Select OPB0 for all operations.
 572          * Will need to be reworked when enabling DMA or anything that uses
 573          * OPB1.
 574          */
 575         writel(0x1, aspeed->base + OPB0_SELECT);
 576
 577         rc = opb_readl(aspeed, ctrl_base + FSI_MVER, &raw);
 578         if (rc) {
 579                 dev_err(&pdev->dev, "failed to read hub version\n");
 580                 return rc;
 581         }
 582
 583         reg = be32_to_cpu(raw);
 584         links = (reg >> 8) & 0xff;
 585         dev_info(&pdev->dev, "hub version %08x (%d links)\n", reg, links);
 586
 587         aspeed->master.dev.parent = &pdev->dev;
 588         aspeed->master.dev.release = aspeed_master_release;
 589         aspeed->master.dev.of_node = of_node_get(dev_of_node(&pdev->dev));
 590
 591         aspeed->master.n_links = links;
 592         aspeed->master.read = aspeed_master_read;
 593         aspeed->master.write = aspeed_master_write;
 594         aspeed->master.send_break = aspeed_master_break;
 595         aspeed->master.term = aspeed_master_term;
 596         aspeed->master.link_enable = aspeed_master_link_enable;
 597
 598         dev_set_drvdata(&pdev->dev, aspeed);
 599
 600         aspeed_master_init(aspeed);
 601
 602         rc = fsi_master_register(&aspeed->master);
 603         if (rc)
 604                 goto err_release;
 605
 606         /* At this point, fsi_master_register performs the device_initialize(),
 607          * and holds the sole reference on master.dev. This means the device
 608          * will be freed (via ->release) during any subsequent call to
 609          * fsi_master_unregister.  We add our own reference to it here, so we
 610          * can perform cleanup (in _remove()) without it being freed before
 611          * we're ready.
 612          */
 613         get_device(&aspeed->master.dev);
 614         return 0;
 615
 616 err_release:
 617         clk_disable_unprepare(aspeed->clk);
 618         return rc;
 619 }
 620
 621 static int fsi_master_aspeed_remove(struct platform_device *pdev)
 622 {
 623         struct fsi_master_aspeed *aspeed = platform_get_drvdata(pdev);
 624
 625         fsi_master_unregister(&aspeed->master);
 626         clk_disable_unprepare(aspeed->clk);
 627
 628         return 0;
 629 }
 630
 631 static const struct of_device_id fsi_master_aspeed_match[] = {
 632         { .compatible = "aspeed,ast2600-fsi-master" },
 633         { },
 634 };
 635
 636 static struct platform_driver fsi_master_aspeed_driver = {
 637         .driver = {
 638                 .name           = "fsi-master-aspeed",
 639                 .of_match_table = fsi_master_aspeed_match,
 640         },
 641         .probe  = fsi_master_aspeed_probe,
 642         .remove = fsi_master_aspeed_remove,
 643 };
 644
 645 module_platform_driver(fsi_master_aspeed_driver);
 646 MODULE_LICENSE("GPL");