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