drivers/usb/gadget/udc/bdc/bdc_core.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * bdc_core.c - BRCM BDC USB3.0 device controller core operations
   4  *
   5  * Copyright (C) 2014 Broadcom Corporation
   6  *
   7  * Author: Ashwini Pahuja
   8  */
   9 #include <linux/module.h>
  10 #include <linux/kernel.h>
  11 #include <linux/slab.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/ioport.h>
  16 #include <linux/io.h>
  17 #include <linux/list.h>
  18 #include <linux/delay.h>
  19 #include <linux/dma-mapping.h>
  20 #include <linux/dmapool.h>
  21 #include <linux/of.h>
  22 #include <linux/phy/phy.h>
  23 #include <linux/moduleparam.h>
  24 #include <linux/usb/ch9.h>
  25 #include <linux/usb/gadget.h>
  26 #include <linux/clk.h>
  27
  28 #include "bdc.h"
  29 #include "bdc_dbg.h"
  30
  31 /* Poll till controller status is not OIP */
  32 static int poll_oip(struct bdc *bdc, int usec)
  33 {
  34         u32 status;
  35         /* Poll till STS!= OIP */
  36         while (usec) {
  37                 status = bdc_readl(bdc->regs, BDC_BDCSC);
  38                 if (BDC_CSTS(status) != BDC_OIP) {
  39                         dev_dbg(bdc->dev,
  40                                 "poll_oip complete status=%d",
  41                                 BDC_CSTS(status));
  42                         return 0;
  43                 }
  44                 udelay(10);
  45                 usec -= 10;
  46         }
  47         dev_err(bdc->dev, "Err: operation timedout BDCSC: 0x%08x\n", status);
  48
  49         return -ETIMEDOUT;
  50 }
  51
  52 /* Stop the BDC controller */
  53 int bdc_stop(struct bdc *bdc)
  54 {
  55         int ret;
  56         u32 temp;
  57
  58         dev_dbg(bdc->dev, "%s ()\n\n", __func__);
  59         temp = bdc_readl(bdc->regs, BDC_BDCSC);
  60         /* Check if BDC is already halted */
  61         if (BDC_CSTS(temp) == BDC_HLT) {
  62                 dev_vdbg(bdc->dev, "BDC already halted\n");
  63                 return 0;
  64         }
  65         temp &= ~BDC_COP_MASK;
  66         temp |= BDC_COS|BDC_COP_STP;
  67         bdc_writel(bdc->regs, BDC_BDCSC, temp);
  68
  69         ret = poll_oip(bdc, BDC_COP_TIMEOUT);
  70         if (ret)
  71                 dev_err(bdc->dev, "bdc stop operation failed");
  72
  73         return ret;
  74 }
  75
  76 /* Issue a reset to BDC controller */
  77 int bdc_reset(struct bdc *bdc)
  78 {
  79         u32 temp;
  80         int ret;
  81
  82         dev_dbg(bdc->dev, "%s ()\n", __func__);
  83         /* First halt the controller */
  84         ret = bdc_stop(bdc);
  85         if (ret)
  86                 return ret;
  87
  88         temp = bdc_readl(bdc->regs, BDC_BDCSC);
  89         temp &= ~BDC_COP_MASK;
  90         temp |= BDC_COS|BDC_COP_RST;
  91         bdc_writel(bdc->regs, BDC_BDCSC, temp);
  92         ret = poll_oip(bdc, BDC_COP_TIMEOUT);
  93         if (ret)
  94                 dev_err(bdc->dev, "bdc reset operation failed");
  95
  96         return ret;
  97 }
  98
  99 /* Run the BDC controller */
 100 int bdc_run(struct bdc *bdc)
 101 {
 102         u32 temp;
 103         int ret;
 104
 105         dev_dbg(bdc->dev, "%s ()\n", __func__);
 106         temp = bdc_readl(bdc->regs, BDC_BDCSC);
 107         /* if BDC is already in running state then do not do anything */
 108         if (BDC_CSTS(temp) == BDC_NOR) {
 109                 dev_warn(bdc->dev, "bdc is already in running state\n");
 110                 return 0;
 111         }
 112         temp &= ~BDC_COP_MASK;
 113         temp |= BDC_COP_RUN;
 114         temp |= BDC_COS;
 115         bdc_writel(bdc->regs, BDC_BDCSC, temp);
 116         ret = poll_oip(bdc, BDC_COP_TIMEOUT);
 117         if (ret) {
 118                 dev_err(bdc->dev, "bdc run operation failed:%d", ret);
 119                 return ret;
 120         }
 121         temp = bdc_readl(bdc->regs, BDC_BDCSC);
 122         if (BDC_CSTS(temp) != BDC_NOR) {
 123                 dev_err(bdc->dev, "bdc not in normal mode after RUN op :%d\n",
 124                                                                 BDC_CSTS(temp));
 125                 return -ESHUTDOWN;
 126         }
 127
 128         return 0;
 129 }
 130
 131 /*
 132  * Present the termination to the host, typically called from upstream port
 133  * event with Vbus present =1
 134  */
 135 void bdc_softconn(struct bdc *bdc)
 136 {
 137         u32 uspc;
 138
 139         uspc = bdc_readl(bdc->regs, BDC_USPC);
 140         uspc &= ~BDC_PST_MASK;
 141         uspc |= BDC_LINK_STATE_RX_DET;
 142         uspc |= BDC_SWS;
 143         dev_dbg(bdc->dev, "%s () uspc=%08x\n", __func__, uspc);
 144         bdc_writel(bdc->regs, BDC_USPC, uspc);
 145 }
 146
 147 /* Remove the termination */
 148 void bdc_softdisconn(struct bdc *bdc)
 149 {
 150         u32 uspc;
 151
 152         uspc = bdc_readl(bdc->regs, BDC_USPC);
 153         uspc |= BDC_SDC;
 154         uspc &= ~BDC_SCN;
 155         dev_dbg(bdc->dev, "%s () uspc=%x\n", __func__, uspc);
 156         bdc_writel(bdc->regs, BDC_USPC, uspc);
 157 }
 158
 159 /* Set up the scratchpad buffer array and scratchpad buffers, if needed. */
 160 static int scratchpad_setup(struct bdc *bdc)
 161 {
 162         int sp_buff_size;
 163         u32 low32;
 164         u32 upp32;
 165
 166         sp_buff_size = BDC_SPB(bdc_readl(bdc->regs, BDC_BDCCFG0));
 167         dev_dbg(bdc->dev, "%s() sp_buff_size=%d\n", __func__, sp_buff_size);
 168         if (!sp_buff_size) {
 169                 dev_dbg(bdc->dev, "Scratchpad buffer not needed\n");
 170                 return 0;
 171         }
 172         /* Refer to BDC spec, Table 4 for description of SPB */
 173         sp_buff_size = 1 << (sp_buff_size + 5);
 174         dev_dbg(bdc->dev, "Allocating %d bytes for scratchpad\n", sp_buff_size);
 175         bdc->scratchpad.buff  =  dma_zalloc_coherent(bdc->dev, sp_buff_size,
 176                                         &bdc->scratchpad.sp_dma, GFP_KERNEL);
 177
 178         if (!bdc->scratchpad.buff)
 179                 goto fail;
 180
 181         bdc->sp_buff_size = sp_buff_size;
 182         bdc->scratchpad.size = sp_buff_size;
 183         low32 = lower_32_bits(bdc->scratchpad.sp_dma);
 184         upp32 = upper_32_bits(bdc->scratchpad.sp_dma);
 185         cpu_to_le32s(&low32);
 186         cpu_to_le32s(&upp32);
 187         bdc_writel(bdc->regs, BDC_SPBBAL, low32);
 188         bdc_writel(bdc->regs, BDC_SPBBAH, upp32);
 189         return 0;
 190
 191 fail:
 192         bdc->scratchpad.buff = NULL;
 193
 194         return -ENOMEM;
 195 }
 196
 197 /* Allocate the status report ring */
 198 static int setup_srr(struct bdc *bdc, int interrupter)
 199 {
 200         dev_dbg(bdc->dev, "%s() NUM_SR_ENTRIES:%d\n", __func__, NUM_SR_ENTRIES);
 201         /* Reset the SRR */
 202         bdc_writel(bdc->regs, BDC_SRRINT(0), BDC_SRR_RWS | BDC_SRR_RST);
 203         bdc->srr.dqp_index = 0;
 204         /* allocate the status report descriptors */
 205         bdc->srr.sr_bds = dma_zalloc_coherent(
 206                                         bdc->dev,
 207                                         NUM_SR_ENTRIES * sizeof(struct bdc_bd),
 208                                         &bdc->srr.dma_addr,
 209                                         GFP_KERNEL);
 210         if (!bdc->srr.sr_bds)
 211                 return -ENOMEM;
 212
 213         return 0;
 214 }
 215
 216 /* Initialize the HW regs and internal data structures */
 217 static void bdc_mem_init(struct bdc *bdc, bool reinit)
 218 {
 219         u8 size = 0;
 220         u32 usb2_pm;
 221         u32 low32;
 222         u32 upp32;
 223         u32 temp;
 224
 225         dev_dbg(bdc->dev, "%s ()\n", __func__);
 226         bdc->ep0_state = WAIT_FOR_SETUP;
 227         bdc->dev_addr = 0;
 228         bdc->srr.eqp_index = 0;
 229         bdc->srr.dqp_index = 0;
 230         bdc->zlp_needed = false;
 231         bdc->delayed_status = false;
 232
 233         bdc_writel(bdc->regs, BDC_SPBBAL, bdc->scratchpad.sp_dma);
 234         /* Init the SRR */
 235         temp = BDC_SRR_RWS | BDC_SRR_RST;
 236         /* Reset the SRR */
 237         bdc_writel(bdc->regs, BDC_SRRINT(0), temp);
 238         dev_dbg(bdc->dev, "bdc->srr.sr_bds =%p\n", bdc->srr.sr_bds);
 239         temp = lower_32_bits(bdc->srr.dma_addr);
 240         size = fls(NUM_SR_ENTRIES) - 2;
 241         temp |= size;
 242         dev_dbg(bdc->dev, "SRRBAL[0]=%08x NUM_SR_ENTRIES:%d size:%d\n",
 243                                                 temp, NUM_SR_ENTRIES, size);
 244
 245         low32 = lower_32_bits(temp);
 246         upp32 = upper_32_bits(bdc->srr.dma_addr);
 247         cpu_to_le32s(&low32);
 248         cpu_to_le32s(&upp32);
 249
 250         /* Write the dma addresses into regs*/
 251         bdc_writel(bdc->regs, BDC_SRRBAL(0), low32);
 252         bdc_writel(bdc->regs, BDC_SRRBAH(0), upp32);
 253
 254         temp = bdc_readl(bdc->regs, BDC_SRRINT(0));
 255         temp |= BDC_SRR_IE;
 256         temp &= ~(BDC_SRR_RST | BDC_SRR_RWS);
 257         bdc_writel(bdc->regs, BDC_SRRINT(0), temp);
 258
 259         /* Set the Interrupt Coalescence ~500 usec */
 260         temp = bdc_readl(bdc->regs, BDC_INTCTLS(0));
 261         temp &= ~0xffff;
 262         temp |= INT_CLS;
 263         bdc_writel(bdc->regs, BDC_INTCTLS(0), temp);
 264
 265         usb2_pm = bdc_readl(bdc->regs, BDC_USPPM2);
 266         dev_dbg(bdc->dev, "usb2_pm=%08x", usb2_pm);
 267         /* Enable hardware LPM Enable */
 268         usb2_pm |= BDC_HLE;
 269         bdc_writel(bdc->regs, BDC_USPPM2, usb2_pm);
 270
 271         /* readback for debug */
 272         usb2_pm = bdc_readl(bdc->regs, BDC_USPPM2);
 273         dev_dbg(bdc->dev, "usb2_pm=%08x\n", usb2_pm);
 274
 275         /* Disable any unwanted SR's on SRR */
 276         temp = bdc_readl(bdc->regs, BDC_BDCSC);
 277         /* We don't want Microframe counter wrap SR */
 278         temp |= BDC_MASK_MCW;
 279         bdc_writel(bdc->regs, BDC_BDCSC, temp);
 280
 281         /*
 282          * In some error cases, driver has to reset the entire BDC controller
 283          * in that case reinit is passed as 1
 284          */
 285         if (reinit) {
 286                 /* Enable interrupts */
 287                 temp = bdc_readl(bdc->regs, BDC_BDCSC);
 288                 temp |= BDC_GIE;
 289                 bdc_writel(bdc->regs, BDC_BDCSC, temp);
 290                 /* Init scratchpad to 0 */
 291                 memset(bdc->scratchpad.buff, 0, bdc->sp_buff_size);
 292                 /* Initialize SRR to 0 */
 293                 memset(bdc->srr.sr_bds, 0,
 294                                         NUM_SR_ENTRIES * sizeof(struct bdc_bd));
 295         } else {
 296                 /* One time initiaization only */
 297                 /* Enable status report function pointers */
 298                 bdc->sr_handler[0] = bdc_sr_xsf;
 299                 bdc->sr_handler[1] = bdc_sr_uspc;
 300
 301                 /* EP0 status report function pointers */
 302                 bdc->sr_xsf_ep0[0] = bdc_xsf_ep0_setup_recv;
 303                 bdc->sr_xsf_ep0[1] = bdc_xsf_ep0_data_start;
 304                 bdc->sr_xsf_ep0[2] = bdc_xsf_ep0_status_start;
 305         }
 306 }
 307
 308 /* Free the dynamic memory */
 309 static void bdc_mem_free(struct bdc *bdc)
 310 {
 311         dev_dbg(bdc->dev, "%s\n", __func__);
 312         /* Free SRR */
 313         if (bdc->srr.sr_bds)
 314                 dma_free_coherent(bdc->dev,
 315                                         NUM_SR_ENTRIES * sizeof(struct bdc_bd),
 316                                         bdc->srr.sr_bds, bdc->srr.dma_addr);
 317
 318         /* Free scratchpad */
 319         if (bdc->scratchpad.buff)
 320                 dma_free_coherent(bdc->dev, bdc->sp_buff_size,
 321                                 bdc->scratchpad.buff, bdc->scratchpad.sp_dma);
 322
 323         /* Destroy the dma pools */
 324         dma_pool_destroy(bdc->bd_table_pool);
 325
 326         /* Free the bdc_ep array */
 327         kfree(bdc->bdc_ep_array);
 328
 329         bdc->srr.sr_bds = NULL;
 330         bdc->scratchpad.buff = NULL;
 331         bdc->bd_table_pool = NULL;
 332         bdc->bdc_ep_array = NULL;
 333 }
 334
 335 /*
 336  * bdc reinit gives a controller reset and reinitialize the registers,
 337  * called from disconnect/bus reset scenario's, to ensure proper HW cleanup
 338  */
 339 int bdc_reinit(struct bdc *bdc)
 340 {
 341         int ret;
 342
 343         dev_dbg(bdc->dev, "%s\n", __func__);
 344         ret = bdc_stop(bdc);
 345         if (ret)
 346                 goto out;
 347
 348         ret = bdc_reset(bdc);
 349         if (ret)
 350                 goto out;
 351
 352         /* the reinit flag is 1 */
 353         bdc_mem_init(bdc, true);
 354         ret = bdc_run(bdc);
 355 out:
 356         bdc->reinit = false;
 357
 358         return ret;
 359 }
 360
 361 /* Allocate all the dyanmic memory */
 362 static int bdc_mem_alloc(struct bdc *bdc)
 363 {
 364         u32 page_size;
 365         unsigned int num_ieps, num_oeps;
 366
 367         dev_dbg(bdc->dev,
 368                 "%s() NUM_BDS_PER_TABLE:%d\n", __func__,
 369                 NUM_BDS_PER_TABLE);
 370         page_size = BDC_PGS(bdc_readl(bdc->regs, BDC_BDCCFG0));
 371         /* page size is 2^pgs KB */
 372         page_size = 1 << page_size;
 373         /* KB */
 374         page_size <<= 10;
 375         dev_dbg(bdc->dev, "page_size=%d\n", page_size);
 376
 377         /* Create a pool of bd tables */
 378         bdc->bd_table_pool =
 379             dma_pool_create("BDC BD tables", bdc->dev, NUM_BDS_PER_TABLE * 16,
 380                                                                 16, page_size);
 381
 382         if (!bdc->bd_table_pool)
 383                 goto fail;
 384
 385         if (scratchpad_setup(bdc))
 386                 goto fail;
 387
 388         /* read from regs */
 389         num_ieps = NUM_NCS(bdc_readl(bdc->regs, BDC_FSCNIC));
 390         num_oeps = NUM_NCS(bdc_readl(bdc->regs, BDC_FSCNOC));
 391         /* +2: 1 for ep0 and the other is rsvd i.e. bdc_ep[0] is rsvd */
 392         bdc->num_eps = num_ieps + num_oeps + 2;
 393         dev_dbg(bdc->dev,
 394                 "ieps:%d eops:%d num_eps:%d\n",
 395                 num_ieps, num_oeps, bdc->num_eps);
 396         /* allocate array of ep pointers */
 397         bdc->bdc_ep_array = kcalloc(bdc->num_eps, sizeof(struct bdc_ep *),
 398                                                                 GFP_KERNEL);
 399         if (!bdc->bdc_ep_array)
 400                 goto fail;
 401
 402         dev_dbg(bdc->dev, "Allocating sr report0\n");
 403         if (setup_srr(bdc, 0))
 404                 goto fail;
 405
 406         return 0;
 407 fail:
 408         dev_warn(bdc->dev, "Couldn't initialize memory\n");
 409         bdc_mem_free(bdc);
 410
 411         return -ENOMEM;
 412 }
 413
 414 /* opposite to bdc_hw_init */
 415 static void bdc_hw_exit(struct bdc *bdc)
 416 {
 417         dev_dbg(bdc->dev, "%s ()\n", __func__);
 418         bdc_mem_free(bdc);
 419 }
 420
 421 /* Initialize the bdc HW and memory */
 422 static int bdc_hw_init(struct bdc *bdc)
 423 {
 424         int ret;
 425
 426         dev_dbg(bdc->dev, "%s ()\n", __func__);
 427         ret = bdc_reset(bdc);
 428         if (ret) {
 429                 dev_err(bdc->dev, "err resetting bdc abort bdc init%d\n", ret);
 430                 return ret;
 431         }
 432         ret = bdc_mem_alloc(bdc);
 433         if (ret) {
 434                 dev_err(bdc->dev, "Mem alloc failed, aborting\n");
 435                 return -ENOMEM;
 436         }
 437         bdc_mem_init(bdc, 0);
 438         bdc_dbg_regs(bdc);
 439         dev_dbg(bdc->dev, "HW Init done\n");
 440
 441         return 0;
 442 }
 443
 444 static int bdc_phy_init(struct bdc *bdc)
 445 {
 446         int phy_num;
 447         int ret;
 448
 449         for (phy_num = 0; phy_num < bdc->num_phys; phy_num++) {
 450                 ret = phy_init(bdc->phys[phy_num]);
 451                 if (ret)
 452                         goto err_exit_phy;
 453                 ret = phy_power_on(bdc->phys[phy_num]);
 454                 if (ret) {
 455                         phy_exit(bdc->phys[phy_num]);
 456                         goto err_exit_phy;
 457                 }
 458         }
 459
 460         return 0;
 461
 462 err_exit_phy:
 463         while (--phy_num >= 0) {
 464                 phy_power_off(bdc->phys[phy_num]);
 465                 phy_exit(bdc->phys[phy_num]);
 466         }
 467
 468         return ret;
 469 }
 470
 471 static void bdc_phy_exit(struct bdc *bdc)
 472 {
 473         int phy_num;
 474
 475         for (phy_num = 0; phy_num < bdc->num_phys; phy_num++) {
 476                 phy_power_off(bdc->phys[phy_num]);
 477                 phy_exit(bdc->phys[phy_num]);
 478         }
 479 }
 480
 481 static int bdc_probe(struct platform_device *pdev)
 482 {
 483         struct bdc *bdc;
 484         struct resource *res;
 485         int ret = -ENOMEM;
 486         int irq;
 487         u32 temp;
 488         struct device *dev = &pdev->dev;
 489         struct clk *clk;
 490         int phy_num;
 491
 492         dev_dbg(dev, "%s()\n", __func__);
 493
 494         clk = devm_clk_get(dev, "sw_usbd");
 495         if (IS_ERR(clk)) {
 496                 dev_info(dev, "Clock not found in Device Tree\n");
 497                 clk = NULL;
 498         }
 499
 500         ret = clk_prepare_enable(clk);
 501         if (ret) {
 502                 dev_err(dev, "could not enable clock\n");
 503                 return ret;
 504         }
 505
 506         bdc = devm_kzalloc(dev, sizeof(*bdc), GFP_KERNEL);
 507         if (!bdc)
 508                 return -ENOMEM;
 509
 510         bdc->clk = clk;
 511
 512         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 513         bdc->regs = devm_ioremap_resource(dev, res);
 514         if (IS_ERR(bdc->regs)) {
 515                 dev_err(dev, "ioremap error\n");
 516                 return -ENOMEM;
 517         }
 518         irq = platform_get_irq(pdev, 0);
 519         if (irq < 0) {
 520                 dev_err(dev, "platform_get_irq failed:%d\n", irq);
 521                 return irq;
 522         }
 523         spin_lock_init(&bdc->lock);
 524         platform_set_drvdata(pdev, bdc);
 525         bdc->irq = irq;
 526         bdc->dev = dev;
 527         dev_dbg(dev, "bdc->regs: %p irq=%d\n", bdc->regs, bdc->irq);
 528
 529         bdc->num_phys = of_count_phandle_with_args(dev->of_node,
 530                                                 "phys", "#phy-cells");
 531         if (bdc->num_phys > 0) {
 532                 bdc->phys = devm_kcalloc(dev, bdc->num_phys,
 533                                         sizeof(struct phy *), GFP_KERNEL);
 534                 if (!bdc->phys)
 535                         return -ENOMEM;
 536         } else {
 537                 bdc->num_phys = 0;
 538         }
 539         dev_info(dev, "Using %d phy(s)\n", bdc->num_phys);
 540
 541         for (phy_num = 0; phy_num < bdc->num_phys; phy_num++) {
 542                 bdc->phys[phy_num] = devm_of_phy_get_by_index(
 543                         dev, dev->of_node, phy_num);
 544                 if (IS_ERR(bdc->phys[phy_num])) {
 545                         ret = PTR_ERR(bdc->phys[phy_num]);
 546                         dev_err(bdc->dev,
 547                                 "BDC phy specified but not found:%d\n", ret);
 548                         return ret;
 549                 }
 550         }
 551
 552         ret = bdc_phy_init(bdc);
 553         if (ret) {
 554                 dev_err(bdc->dev, "BDC phy init failure:%d\n", ret);
 555                 return ret;
 556         }
 557
 558         temp = bdc_readl(bdc->regs, BDC_BDCCAP1);
 559         if ((temp & BDC_P64) &&
 560                         !dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64))) {
 561                 dev_dbg(dev, "Using 64-bit address\n");
 562         } else {
 563                 ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
 564                 if (ret) {
 565                         dev_err(dev,
 566                                 "No suitable DMA config available, abort\n");
 567                         return -ENOTSUPP;
 568                 }
 569                 dev_dbg(dev, "Using 32-bit address\n");
 570         }
 571         ret = bdc_hw_init(bdc);
 572         if (ret) {
 573                 dev_err(dev, "BDC init failure:%d\n", ret);
 574                 goto phycleanup;
 575         }
 576         ret = bdc_udc_init(bdc);
 577         if (ret) {
 578                 dev_err(dev, "BDC Gadget init failure:%d\n", ret);
 579                 goto cleanup;
 580         }
 581         return 0;
 582
 583 cleanup:
 584         bdc_hw_exit(bdc);
 585 phycleanup:
 586         bdc_phy_exit(bdc);
 587         return ret;
 588 }
 589
 590 static int bdc_remove(struct platform_device *pdev)
 591 {
 592         struct bdc *bdc;
 593
 594         bdc  = platform_get_drvdata(pdev);
 595         dev_dbg(bdc->dev, "%s ()\n", __func__);
 596         bdc_udc_exit(bdc);
 597         bdc_hw_exit(bdc);
 598         bdc_phy_exit(bdc);
 599         clk_disable_unprepare(bdc->clk);
 600         return 0;
 601 }
 602
 603 #ifdef CONFIG_PM_SLEEP
 604 static int bdc_suspend(struct device *dev)
 605 {
 606         struct bdc *bdc = dev_get_drvdata(dev);
 607
 608         clk_disable_unprepare(bdc->clk);
 609         return 0;
 610 }
 611
 612 static int bdc_resume(struct device *dev)
 613 {
 614         struct bdc *bdc = dev_get_drvdata(dev);
 615         int ret;
 616
 617         ret = clk_prepare_enable(bdc->clk);
 618         if (ret) {
 619                 dev_err(bdc->dev, "err enabling the clock\n");
 620                 return ret;
 621         }
 622         ret = bdc_reinit(bdc);
 623         if (ret) {
 624                 dev_err(bdc->dev, "err in bdc reinit\n");
 625                 return ret;
 626         }
 627
 628         return 0;
 629 }
 630
 631 #endif /* CONFIG_PM_SLEEP */
 632
 633 static SIMPLE_DEV_PM_OPS(bdc_pm_ops, bdc_suspend,
 634                 bdc_resume);
 635
 636 static const struct of_device_id bdc_of_match[] = {
 637         { .compatible = "brcm,bdc-v0.16" },
 638         { .compatible = "brcm,bdc" },
 639         { /* sentinel */ }
 640 };
 641
 642 static struct platform_driver bdc_driver = {
 643         .driver         = {
 644                 .name   = BRCM_BDC_NAME,
 645                 .pm = &bdc_pm_ops,
 646                 .of_match_table = bdc_of_match,
 647         },
 648         .probe          = bdc_probe,
 649         .remove         = bdc_remove,
 650 };
 651
 652 module_platform_driver(bdc_driver);
 653 MODULE_AUTHOR("Ashwini Pahuja <ashwini.linux@gmail.com>");
 654 MODULE_LICENSE("GPL");
 655 MODULE_DESCRIPTION(BRCM_BDC_DESC);