drivers/hsi/controllers/omap_ssi_core.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* OMAP SSI driver.
   3  *
   4  * Copyright (C) 2010 Nokia Corporation. All rights reserved.
   5  * Copyright (C) 2014 Sebastian Reichel <[email protected]>
   6  *
   7  * Contact: Carlos Chinea <[email protected]>
   8  */
   9
  10 #include <linux/compiler.h>
  11 #include <linux/err.h>
  12 #include <linux/ioport.h>
  13 #include <linux/io.h>
  14 #include <linux/clk.h>
  15 #include <linux/device.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/dma-mapping.h>
  18 #include <linux/dmaengine.h>
  19 #include <linux/delay.h>
  20 #include <linux/hsi/ssi_protocol.h>
  21 #include <linux/seq_file.h>
  22 #include <linux/scatterlist.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/spinlock.h>
  25 #include <linux/debugfs.h>
  26 #include <linux/pinctrl/consumer.h>
  27 #include <linux/pm_runtime.h>
  28 #include <linux/of_platform.h>
  29 #include <linux/hsi/hsi.h>
  30 #include <linux/idr.h>
  31
  32 #include "omap_ssi_regs.h"
  33 #include "omap_ssi.h"
  34
  35 /* For automatically allocated device IDs */
  36 static DEFINE_IDA(platform_omap_ssi_ida);
  37
  38 #ifdef CONFIG_DEBUG_FS
  39 static int ssi_regs_show(struct seq_file *m, void *p __maybe_unused)
  40 {
  41         struct hsi_controller *ssi = m->private;
  42         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
  43         void __iomem *sys = omap_ssi->sys;
  44
  45         pm_runtime_get_sync(ssi->device.parent);
  46         seq_printf(m, "REVISION\t: 0x%08x\n",  readl(sys + SSI_REVISION_REG));
  47         seq_printf(m, "SYSCONFIG\t: 0x%08x\n", readl(sys + SSI_SYSCONFIG_REG));
  48         seq_printf(m, "SYSSTATUS\t: 0x%08x\n", readl(sys + SSI_SYSSTATUS_REG));
  49         pm_runtime_put(ssi->device.parent);
  50
  51         return 0;
  52 }
  53
  54 static int ssi_gdd_regs_show(struct seq_file *m, void *p __maybe_unused)
  55 {
  56         struct hsi_controller *ssi = m->private;
  57         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
  58         void __iomem *gdd = omap_ssi->gdd;
  59         void __iomem *sys = omap_ssi->sys;
  60         int lch;
  61
  62         pm_runtime_get_sync(ssi->device.parent);
  63
  64         seq_printf(m, "GDD_MPU_STATUS\t: 0x%08x\n",
  65                 readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG));
  66         seq_printf(m, "GDD_MPU_ENABLE\t: 0x%08x\n\n",
  67                 readl(sys + SSI_GDD_MPU_IRQ_ENABLE_REG));
  68         seq_printf(m, "HW_ID\t\t: 0x%08x\n",
  69                                 readl(gdd + SSI_GDD_HW_ID_REG));
  70         seq_printf(m, "PPORT_ID\t: 0x%08x\n",
  71                                 readl(gdd + SSI_GDD_PPORT_ID_REG));
  72         seq_printf(m, "MPORT_ID\t: 0x%08x\n",
  73                                 readl(gdd + SSI_GDD_MPORT_ID_REG));
  74         seq_printf(m, "TEST\t\t: 0x%08x\n",
  75                                 readl(gdd + SSI_GDD_TEST_REG));
  76         seq_printf(m, "GCR\t\t: 0x%08x\n",
  77                                 readl(gdd + SSI_GDD_GCR_REG));
  78
  79         for (lch = 0; lch < SSI_MAX_GDD_LCH; lch++) {
  80                 seq_printf(m, "\nGDD LCH %d\n=========\n", lch);
  81                 seq_printf(m, "CSDP\t\t: 0x%04x\n",
  82                                 readw(gdd + SSI_GDD_CSDP_REG(lch)));
  83                 seq_printf(m, "CCR\t\t: 0x%04x\n",
  84                                 readw(gdd + SSI_GDD_CCR_REG(lch)));
  85                 seq_printf(m, "CICR\t\t: 0x%04x\n",
  86                                 readw(gdd + SSI_GDD_CICR_REG(lch)));
  87                 seq_printf(m, "CSR\t\t: 0x%04x\n",
  88                                 readw(gdd + SSI_GDD_CSR_REG(lch)));
  89                 seq_printf(m, "CSSA\t\t: 0x%08x\n",
  90                                 readl(gdd + SSI_GDD_CSSA_REG(lch)));
  91                 seq_printf(m, "CDSA\t\t: 0x%08x\n",
  92                                 readl(gdd + SSI_GDD_CDSA_REG(lch)));
  93                 seq_printf(m, "CEN\t\t: 0x%04x\n",
  94                                 readw(gdd + SSI_GDD_CEN_REG(lch)));
  95                 seq_printf(m, "CSAC\t\t: 0x%04x\n",
  96                                 readw(gdd + SSI_GDD_CSAC_REG(lch)));
  97                 seq_printf(m, "CDAC\t\t: 0x%04x\n",
  98                                 readw(gdd + SSI_GDD_CDAC_REG(lch)));
  99                 seq_printf(m, "CLNK_CTRL\t: 0x%04x\n",
 100                                 readw(gdd + SSI_GDD_CLNK_CTRL_REG(lch)));
 101         }
 102
 103         pm_runtime_put(ssi->device.parent);
 104
 105         return 0;
 106 }
 107
 108 DEFINE_SHOW_ATTRIBUTE(ssi_regs);
 109 DEFINE_SHOW_ATTRIBUTE(ssi_gdd_regs);
 110
 111 static int ssi_debug_add_ctrl(struct hsi_controller *ssi)
 112 {
 113         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 114         struct dentry *dir;
 115
 116         /* SSI controller */
 117         omap_ssi->dir = debugfs_create_dir(dev_name(&ssi->device), NULL);
 118         if (!omap_ssi->dir)
 119                 return -ENOMEM;
 120
 121         debugfs_create_file("regs", S_IRUGO, omap_ssi->dir, ssi,
 122                                                                 &ssi_regs_fops);
 123         /* SSI GDD (DMA) */
 124         dir = debugfs_create_dir("gdd", omap_ssi->dir);
 125         if (!dir)
 126                 goto rback;
 127         debugfs_create_file("regs", S_IRUGO, dir, ssi, &ssi_gdd_regs_fops);
 128
 129         return 0;
 130 rback:
 131         debugfs_remove_recursive(omap_ssi->dir);
 132
 133         return -ENOMEM;
 134 }
 135
 136 static void ssi_debug_remove_ctrl(struct hsi_controller *ssi)
 137 {
 138         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 139
 140         debugfs_remove_recursive(omap_ssi->dir);
 141 }
 142 #endif /* CONFIG_DEBUG_FS */
 143
 144 /*
 145  * FIXME: Horrible HACK needed until we remove the useless wakeline test
 146  * in the CMT. To be removed !!!!
 147  */
 148 void ssi_waketest(struct hsi_client *cl, unsigned int enable)
 149 {
 150         struct hsi_port *port = hsi_get_port(cl);
 151         struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
 152         struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
 153         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 154
 155         omap_port->wktest = !!enable;
 156         if (omap_port->wktest) {
 157                 pm_runtime_get_sync(ssi->device.parent);
 158                 writel_relaxed(SSI_WAKE(0),
 159                                 omap_ssi->sys + SSI_SET_WAKE_REG(port->num));
 160         } else {
 161                 writel_relaxed(SSI_WAKE(0),
 162                                 omap_ssi->sys + SSI_CLEAR_WAKE_REG(port->num));
 163                 pm_runtime_put(ssi->device.parent);
 164         }
 165 }
 166 EXPORT_SYMBOL_GPL(ssi_waketest);
 167
 168 static void ssi_gdd_complete(struct hsi_controller *ssi, unsigned int lch)
 169 {
 170         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 171         struct hsi_msg *msg = omap_ssi->gdd_trn[lch].msg;
 172         struct hsi_port *port = to_hsi_port(msg->cl->device.parent);
 173         struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
 174         unsigned int dir;
 175         u32 csr;
 176         u32 val;
 177
 178         spin_lock(&omap_ssi->lock);
 179
 180         val = readl(omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
 181         val &= ~SSI_GDD_LCH(lch);
 182         writel_relaxed(val, omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
 183
 184         if (msg->ttype == HSI_MSG_READ) {
 185                 dir = DMA_FROM_DEVICE;
 186                 val = SSI_DATAAVAILABLE(msg->channel);
 187                 pm_runtime_put(omap_port->pdev);
 188         } else {
 189                 dir = DMA_TO_DEVICE;
 190                 val = SSI_DATAACCEPT(msg->channel);
 191                 /* Keep clocks reference for write pio event */
 192         }
 193         dma_unmap_sg(&ssi->device, msg->sgt.sgl, msg->sgt.nents, dir);
 194         csr = readw(omap_ssi->gdd + SSI_GDD_CSR_REG(lch));
 195         omap_ssi->gdd_trn[lch].msg = NULL; /* release GDD lch */
 196         dev_dbg(&port->device, "DMA completed ch %d ttype %d\n",
 197                                 msg->channel, msg->ttype);
 198         spin_unlock(&omap_ssi->lock);
 199         if (csr & SSI_CSR_TOUR) { /* Timeout error */
 200                 msg->status = HSI_STATUS_ERROR;
 201                 msg->actual_len = 0;
 202                 spin_lock(&omap_port->lock);
 203                 list_del(&msg->link); /* Dequeue msg */
 204                 spin_unlock(&omap_port->lock);
 205
 206                 list_add_tail(&msg->link, &omap_port->errqueue);
 207                 schedule_delayed_work(&omap_port->errqueue_work, 0);
 208                 return;
 209         }
 210         spin_lock(&omap_port->lock);
 211         val |= readl(omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
 212         writel_relaxed(val, omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
 213         spin_unlock(&omap_port->lock);
 214
 215         msg->status = HSI_STATUS_COMPLETED;
 216         msg->actual_len = sg_dma_len(msg->sgt.sgl);
 217 }
 218
 219 static void ssi_gdd_tasklet(unsigned long dev)
 220 {
 221         struct hsi_controller *ssi = (struct hsi_controller *)dev;
 222         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 223         void __iomem *sys = omap_ssi->sys;
 224         unsigned int lch;
 225         u32 status_reg;
 226
 227         pm_runtime_get(ssi->device.parent);
 228
 229         if (!pm_runtime_active(ssi->device.parent)) {
 230                 dev_warn(ssi->device.parent, "ssi_gdd_tasklet called without runtime PM!\n");
 231                 pm_runtime_put(ssi->device.parent);
 232                 return;
 233         }
 234
 235         status_reg = readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG);
 236         for (lch = 0; lch < SSI_MAX_GDD_LCH; lch++) {
 237                 if (status_reg & SSI_GDD_LCH(lch))
 238                         ssi_gdd_complete(ssi, lch);
 239         }
 240         writel_relaxed(status_reg, sys + SSI_GDD_MPU_IRQ_STATUS_REG);
 241         status_reg = readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG);
 242
 243         pm_runtime_put(ssi->device.parent);
 244
 245         if (status_reg)
 246                 tasklet_hi_schedule(&omap_ssi->gdd_tasklet);
 247         else
 248                 enable_irq(omap_ssi->gdd_irq);
 249
 250 }
 251
 252 static irqreturn_t ssi_gdd_isr(int irq, void *ssi)
 253 {
 254         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 255
 256         tasklet_hi_schedule(&omap_ssi->gdd_tasklet);
 257         disable_irq_nosync(irq);
 258
 259         return IRQ_HANDLED;
 260 }
 261
 262 static unsigned long ssi_get_clk_rate(struct hsi_controller *ssi)
 263 {
 264         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 265         unsigned long rate = clk_get_rate(omap_ssi->fck);
 266         return rate;
 267 }
 268
 269 static int ssi_clk_event(struct notifier_block *nb, unsigned long event,
 270                                                                 void *data)
 271 {
 272         struct omap_ssi_controller *omap_ssi = container_of(nb,
 273                                         struct omap_ssi_controller, fck_nb);
 274         struct hsi_controller *ssi = to_hsi_controller(omap_ssi->dev);
 275         struct clk_notifier_data *clk_data = data;
 276         struct omap_ssi_port *omap_port;
 277         int i;
 278
 279         switch (event) {
 280         case PRE_RATE_CHANGE:
 281                 dev_dbg(&ssi->device, "pre rate change\n");
 282
 283                 for (i = 0; i < ssi->num_ports; i++) {
 284                         omap_port = omap_ssi->port[i];
 285
 286                         if (!omap_port)
 287                                 continue;
 288
 289                         /* Workaround for SWBREAK + CAwake down race in CMT */
 290                         disable_irq(omap_port->wake_irq);
 291
 292                         /* stop all ssi communication */
 293                         pinctrl_pm_select_idle_state(omap_port->pdev);
 294                         udelay(1); /* wait for racing frames */
 295                 }
 296
 297                 break;
 298         case ABORT_RATE_CHANGE:
 299                 dev_dbg(&ssi->device, "abort rate change\n");
 300                 fallthrough;
 301         case POST_RATE_CHANGE:
 302                 dev_dbg(&ssi->device, "post rate change (%lu -> %lu)\n",
 303                         clk_data->old_rate, clk_data->new_rate);
 304                 omap_ssi->fck_rate = DIV_ROUND_CLOSEST(clk_data->new_rate, 1000); /* kHz */
 305
 306                 for (i = 0; i < ssi->num_ports; i++) {
 307                         omap_port = omap_ssi->port[i];
 308
 309                         if (!omap_port)
 310                                 continue;
 311
 312                         omap_ssi_port_update_fclk(ssi, omap_port);
 313
 314                         /* resume ssi communication */
 315                         pinctrl_pm_select_default_state(omap_port->pdev);
 316                         enable_irq(omap_port->wake_irq);
 317                 }
 318
 319                 break;
 320         default:
 321                 break;
 322         }
 323
 324         return NOTIFY_DONE;
 325 }
 326
 327 static int ssi_get_iomem(struct platform_device *pd,
 328                 const char *name, void __iomem **pbase, dma_addr_t *phy)
 329 {
 330         struct resource *mem;
 331         void __iomem *base;
 332         struct hsi_controller *ssi = platform_get_drvdata(pd);
 333
 334         mem = platform_get_resource_byname(pd, IORESOURCE_MEM, name);
 335         base = devm_ioremap_resource(&ssi->device, mem);
 336         if (IS_ERR(base))
 337                 return PTR_ERR(base);
 338
 339         *pbase = base;
 340
 341         if (phy)
 342                 *phy = mem->start;
 343
 344         return 0;
 345 }
 346
 347 static int ssi_add_controller(struct hsi_controller *ssi,
 348                                                 struct platform_device *pd)
 349 {
 350         struct omap_ssi_controller *omap_ssi;
 351         int err;
 352
 353         omap_ssi = devm_kzalloc(&ssi->device, sizeof(*omap_ssi), GFP_KERNEL);
 354         if (!omap_ssi)
 355                 return -ENOMEM;
 356
 357         err = ida_simple_get(&platform_omap_ssi_ida, 0, 0, GFP_KERNEL);
 358         if (err < 0)
 359                 return err;
 360         ssi->id = err;
 361
 362         ssi->owner = THIS_MODULE;
 363         ssi->device.parent = &pd->dev;
 364         dev_set_name(&ssi->device, "ssi%d", ssi->id);
 365         hsi_controller_set_drvdata(ssi, omap_ssi);
 366         omap_ssi->dev = &ssi->device;
 367         err = ssi_get_iomem(pd, "sys", &omap_ssi->sys, NULL);
 368         if (err < 0)
 369                 goto out_err;
 370         err = ssi_get_iomem(pd, "gdd", &omap_ssi->gdd, NULL);
 371         if (err < 0)
 372                 goto out_err;
 373         err = platform_get_irq_byname(pd, "gdd_mpu");
 374         if (err < 0)
 375                 goto out_err;
 376         omap_ssi->gdd_irq = err;
 377         tasklet_init(&omap_ssi->gdd_tasklet, ssi_gdd_tasklet,
 378                                                         (unsigned long)ssi);
 379         err = devm_request_irq(&ssi->device, omap_ssi->gdd_irq, ssi_gdd_isr,
 380                                                 0, "gdd_mpu", ssi);
 381         if (err < 0) {
 382                 dev_err(&ssi->device, "Request GDD IRQ %d failed (%d)",
 383                                                         omap_ssi->gdd_irq, err);
 384                 goto out_err;
 385         }
 386
 387         omap_ssi->port = devm_kcalloc(&ssi->device, ssi->num_ports,
 388                                       sizeof(*omap_ssi->port), GFP_KERNEL);
 389         if (!omap_ssi->port) {
 390                 err = -ENOMEM;
 391                 goto out_err;
 392         }
 393
 394         omap_ssi->fck = devm_clk_get(&ssi->device, "ssi_ssr_fck");
 395         if (IS_ERR(omap_ssi->fck)) {
 396                 dev_err(&pd->dev, "Could not acquire clock \"ssi_ssr_fck\": %li\n",
 397                         PTR_ERR(omap_ssi->fck));
 398                 err = -ENODEV;
 399                 goto out_err;
 400         }
 401
 402         omap_ssi->fck_nb.notifier_call = ssi_clk_event;
 403         omap_ssi->fck_nb.priority = INT_MAX;
 404         clk_notifier_register(omap_ssi->fck, &omap_ssi->fck_nb);
 405
 406         /* TODO: find register, which can be used to detect context loss */
 407         omap_ssi->get_loss = NULL;
 408
 409         omap_ssi->max_speed = UINT_MAX;
 410         spin_lock_init(&omap_ssi->lock);
 411         err = hsi_register_controller(ssi);
 412
 413         if (err < 0)
 414                 goto out_err;
 415
 416         return 0;
 417
 418 out_err:
 419         ida_simple_remove(&platform_omap_ssi_ida, ssi->id);
 420         return err;
 421 }
 422
 423 static int ssi_hw_init(struct hsi_controller *ssi)
 424 {
 425         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 426         int err;
 427
 428         err = pm_runtime_resume_and_get(ssi->device.parent);
 429         if (err < 0) {
 430                 dev_err(&ssi->device, "runtime PM failed %d\n", err);
 431                 return err;
 432         }
 433         /* Resetting GDD */
 434         writel_relaxed(SSI_SWRESET, omap_ssi->gdd + SSI_GDD_GRST_REG);
 435         /* Get FCK rate in kHz */
 436         omap_ssi->fck_rate = DIV_ROUND_CLOSEST(ssi_get_clk_rate(ssi), 1000);
 437         dev_dbg(&ssi->device, "SSI fck rate %lu kHz\n", omap_ssi->fck_rate);
 438
 439         writel_relaxed(SSI_CLK_AUTOGATING_ON, omap_ssi->sys + SSI_GDD_GCR_REG);
 440         omap_ssi->gdd_gcr = SSI_CLK_AUTOGATING_ON;
 441         pm_runtime_put_sync(ssi->device.parent);
 442
 443         return 0;
 444 }
 445
 446 static void ssi_remove_controller(struct hsi_controller *ssi)
 447 {
 448         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 449         int id = ssi->id;
 450         tasklet_kill(&omap_ssi->gdd_tasklet);
 451         hsi_unregister_controller(ssi);
 452         clk_notifier_unregister(omap_ssi->fck, &omap_ssi->fck_nb);
 453         ida_simple_remove(&platform_omap_ssi_ida, id);
 454 }
 455
 456 static inline int ssi_of_get_available_ports_count(const struct device_node *np)
 457 {
 458         struct device_node *child;
 459         int num = 0;
 460
 461         for_each_available_child_of_node(np, child)
 462                 if (of_device_is_compatible(child, "ti,omap3-ssi-port"))
 463                         num++;
 464
 465         return num;
 466 }
 467
 468 static int ssi_remove_ports(struct device *dev, void *c)
 469 {
 470         struct platform_device *pdev = to_platform_device(dev);
 471
 472         if (!dev->of_node)
 473                 return 0;
 474
 475         of_node_clear_flag(dev->of_node, OF_POPULATED);
 476         of_device_unregister(pdev);
 477
 478         return 0;
 479 }
 480
 481 static int ssi_probe(struct platform_device *pd)
 482 {
 483         struct platform_device *childpdev;
 484         struct device_node *np = pd->dev.of_node;
 485         struct device_node *child;
 486         struct hsi_controller *ssi;
 487         int err;
 488         int num_ports;
 489
 490         if (!np) {
 491                 dev_err(&pd->dev, "missing device tree data\n");
 492                 return -EINVAL;
 493         }
 494
 495         num_ports = ssi_of_get_available_ports_count(np);
 496
 497         ssi = hsi_alloc_controller(num_ports, GFP_KERNEL);
 498         if (!ssi) {
 499                 dev_err(&pd->dev, "No memory for controller\n");
 500                 return -ENOMEM;
 501         }
 502
 503         platform_set_drvdata(pd, ssi);
 504
 505         err = ssi_add_controller(ssi, pd);
 506         if (err < 0) {
 507                 hsi_put_controller(ssi);
 508                 goto out1;
 509         }
 510
 511         pm_runtime_enable(&pd->dev);
 512
 513         err = ssi_hw_init(ssi);
 514         if (err < 0)
 515                 goto out2;
 516 #ifdef CONFIG_DEBUG_FS
 517         err = ssi_debug_add_ctrl(ssi);
 518         if (err < 0)
 519                 goto out2;
 520 #endif
 521
 522         for_each_available_child_of_node(np, child) {
 523                 if (!of_device_is_compatible(child, "ti,omap3-ssi-port"))
 524                         continue;
 525
 526                 childpdev = of_platform_device_create(child, NULL, &pd->dev);
 527                 if (!childpdev) {
 528                         err = -ENODEV;
 529                         dev_err(&pd->dev, "failed to create ssi controller port\n");
 530                         of_node_put(child);
 531                         goto out3;
 532                 }
 533         }
 534
 535         dev_info(&pd->dev, "ssi controller %d initialized (%d ports)!\n",
 536                 ssi->id, num_ports);
 537         return err;
 538 out3:
 539         device_for_each_child(&pd->dev, NULL, ssi_remove_ports);
 540 out2:
 541         ssi_remove_controller(ssi);
 542         pm_runtime_disable(&pd->dev);
 543 out1:
 544         platform_set_drvdata(pd, NULL);
 545
 546         return err;
 547 }
 548
 549 static int ssi_remove(struct platform_device *pd)
 550 {
 551         struct hsi_controller *ssi = platform_get_drvdata(pd);
 552
 553         /* cleanup of of_platform_populate() call */
 554         device_for_each_child(&pd->dev, NULL, ssi_remove_ports);
 555
 556 #ifdef CONFIG_DEBUG_FS
 557         ssi_debug_remove_ctrl(ssi);
 558 #endif
 559         ssi_remove_controller(ssi);
 560         platform_set_drvdata(pd, NULL);
 561
 562         pm_runtime_disable(&pd->dev);
 563
 564         return 0;
 565 }
 566
 567 #ifdef CONFIG_PM
 568 static int omap_ssi_runtime_suspend(struct device *dev)
 569 {
 570         struct hsi_controller *ssi = dev_get_drvdata(dev);
 571         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 572
 573         dev_dbg(dev, "runtime suspend!\n");
 574
 575         if (omap_ssi->get_loss)
 576                 omap_ssi->loss_count =
 577                                 omap_ssi->get_loss(ssi->device.parent);
 578
 579         return 0;
 580 }
 581
 582 static int omap_ssi_runtime_resume(struct device *dev)
 583 {
 584         struct hsi_controller *ssi = dev_get_drvdata(dev);
 585         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 586
 587         dev_dbg(dev, "runtime resume!\n");
 588
 589         if ((omap_ssi->get_loss) && (omap_ssi->loss_count ==
 590                                 omap_ssi->get_loss(ssi->device.parent)))
 591                 return 0;
 592
 593         writel_relaxed(omap_ssi->gdd_gcr, omap_ssi->gdd + SSI_GDD_GCR_REG);
 594
 595         return 0;
 596 }
 597
 598 static const struct dev_pm_ops omap_ssi_pm_ops = {
 599         SET_RUNTIME_PM_OPS(omap_ssi_runtime_suspend, omap_ssi_runtime_resume,
 600                 NULL)
 601 };
 602
 603 #define DEV_PM_OPS     (&omap_ssi_pm_ops)
 604 #else
 605 #define DEV_PM_OPS     NULL
 606 #endif
 607
 608 #ifdef CONFIG_OF
 609 static const struct of_device_id omap_ssi_of_match[] = {
 610         { .compatible = "ti,omap3-ssi", },
 611         {},
 612 };
 613 MODULE_DEVICE_TABLE(of, omap_ssi_of_match);
 614 #else
 615 #define omap_ssi_of_match NULL
 616 #endif
 617
 618 static struct platform_driver ssi_pdriver = {
 619         .probe = ssi_probe,
 620         .remove = ssi_remove,
 621         .driver = {
 622                 .name   = "omap_ssi",
 623                 .pm     = DEV_PM_OPS,
 624                 .of_match_table = omap_ssi_of_match,
 625         },
 626 };
 627
 628 static int __init ssi_init(void) {
 629         int ret;
 630
 631         ret = platform_driver_register(&ssi_pdriver);
 632         if (ret)
 633                 return ret;
 634
 635         ret = platform_driver_register(&ssi_port_pdriver);
 636         if (ret) {
 637                 platform_driver_unregister(&ssi_pdriver);
 638                 return ret;
 639         }
 640
 641         return 0;
 642 }
 643 module_init(ssi_init);
 644
 645 static void __exit ssi_exit(void) {
 646         platform_driver_unregister(&ssi_port_pdriver);
 647         platform_driver_unregister(&ssi_pdriver);
 648 }
 649 module_exit(ssi_exit);
 650
 651 MODULE_ALIAS("platform:omap_ssi");
 652 MODULE_AUTHOR("Carlos Chinea <[email protected]>");
 653 MODULE_AUTHOR("Sebastian Reichel <[email protected]>");
 654 MODULE_DESCRIPTION("Synchronous Serial Interface Driver");
 655 MODULE_LICENSE("GPL v2");