drivers/hsi/controllers/omap_ssi_core.c

   1 /* OMAP SSI driver.
   2  *
   3  * Copyright (C) 2010 Nokia Corporation. All rights reserved.
   4  * Copyright (C) 2014 Sebastian Reichel <sre@kernel.org>
   5  *
   6  * Contact: Carlos Chinea <carlos.chinea@nokia.com>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * version 2 as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  20  * 02110-1301 USA
  21  */
  22
  23 #include <linux/compiler.h>
  24 #include <linux/err.h>
  25 #include <linux/ioport.h>
  26 #include <linux/io.h>
  27 #include <linux/clk.h>
  28 #include <linux/device.h>
  29 #include <linux/platform_device.h>
  30 #include <linux/dma-mapping.h>
  31 #include <linux/dmaengine.h>
  32 #include <linux/delay.h>
  33 #include <linux/seq_file.h>
  34 #include <linux/scatterlist.h>
  35 #include <linux/interrupt.h>
  36 #include <linux/spinlock.h>
  37 #include <linux/debugfs.h>
  38 #include <linux/pinctrl/consumer.h>
  39 #include <linux/pm_runtime.h>
  40 #include <linux/of_platform.h>
  41 #include <linux/hsi/hsi.h>
  42 #include <linux/idr.h>
  43
  44 #include "omap_ssi_regs.h"
  45 #include "omap_ssi.h"
  46
  47 /* For automatically allocated device IDs */
  48 static DEFINE_IDA(platform_omap_ssi_ida);
  49
  50 #ifdef CONFIG_DEBUG_FS
  51 static int ssi_debug_show(struct seq_file *m, void *p __maybe_unused)
  52 {
  53         struct hsi_controller *ssi = m->private;
  54         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
  55         void __iomem *sys = omap_ssi->sys;
  56
  57         pm_runtime_get_sync(ssi->device.parent);
  58         seq_printf(m, "REVISION\t: 0x%08x\n",  readl(sys + SSI_REVISION_REG));
  59         seq_printf(m, "SYSCONFIG\t: 0x%08x\n", readl(sys + SSI_SYSCONFIG_REG));
  60         seq_printf(m, "SYSSTATUS\t: 0x%08x\n", readl(sys + SSI_SYSSTATUS_REG));
  61         pm_runtime_put(ssi->device.parent);
  62
  63         return 0;
  64 }
  65
  66 static int ssi_debug_gdd_show(struct seq_file *m, void *p __maybe_unused)
  67 {
  68         struct hsi_controller *ssi = m->private;
  69         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
  70         void __iomem *gdd = omap_ssi->gdd;
  71         void __iomem *sys = omap_ssi->sys;
  72         int lch;
  73
  74         pm_runtime_get_sync(ssi->device.parent);
  75
  76         seq_printf(m, "GDD_MPU_STATUS\t: 0x%08x\n",
  77                 readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG));
  78         seq_printf(m, "GDD_MPU_ENABLE\t: 0x%08x\n\n",
  79                 readl(sys + SSI_GDD_MPU_IRQ_ENABLE_REG));
  80         seq_printf(m, "HW_ID\t\t: 0x%08x\n",
  81                                 readl(gdd + SSI_GDD_HW_ID_REG));
  82         seq_printf(m, "PPORT_ID\t: 0x%08x\n",
  83                                 readl(gdd + SSI_GDD_PPORT_ID_REG));
  84         seq_printf(m, "MPORT_ID\t: 0x%08x\n",
  85                                 readl(gdd + SSI_GDD_MPORT_ID_REG));
  86         seq_printf(m, "TEST\t\t: 0x%08x\n",
  87                                 readl(gdd + SSI_GDD_TEST_REG));
  88         seq_printf(m, "GCR\t\t: 0x%08x\n",
  89                                 readl(gdd + SSI_GDD_GCR_REG));
  90
  91         for (lch = 0; lch < SSI_MAX_GDD_LCH; lch++) {
  92                 seq_printf(m, "\nGDD LCH %d\n=========\n", lch);
  93                 seq_printf(m, "CSDP\t\t: 0x%04x\n",
  94                                 readw(gdd + SSI_GDD_CSDP_REG(lch)));
  95                 seq_printf(m, "CCR\t\t: 0x%04x\n",
  96                                 readw(gdd + SSI_GDD_CCR_REG(lch)));
  97                 seq_printf(m, "CICR\t\t: 0x%04x\n",
  98                                 readw(gdd + SSI_GDD_CICR_REG(lch)));
  99                 seq_printf(m, "CSR\t\t: 0x%04x\n",
 100                                 readw(gdd + SSI_GDD_CSR_REG(lch)));
 101                 seq_printf(m, "CSSA\t\t: 0x%08x\n",
 102                                 readl(gdd + SSI_GDD_CSSA_REG(lch)));
 103                 seq_printf(m, "CDSA\t\t: 0x%08x\n",
 104                                 readl(gdd + SSI_GDD_CDSA_REG(lch)));
 105                 seq_printf(m, "CEN\t\t: 0x%04x\n",
 106                                 readw(gdd + SSI_GDD_CEN_REG(lch)));
 107                 seq_printf(m, "CSAC\t\t: 0x%04x\n",
 108                                 readw(gdd + SSI_GDD_CSAC_REG(lch)));
 109                 seq_printf(m, "CDAC\t\t: 0x%04x\n",
 110                                 readw(gdd + SSI_GDD_CDAC_REG(lch)));
 111                 seq_printf(m, "CLNK_CTRL\t: 0x%04x\n",
 112                                 readw(gdd + SSI_GDD_CLNK_CTRL_REG(lch)));
 113         }
 114
 115         pm_runtime_put(ssi->device.parent);
 116
 117         return 0;
 118 }
 119
 120 static int ssi_regs_open(struct inode *inode, struct file *file)
 121 {
 122         return single_open(file, ssi_debug_show, inode->i_private);
 123 }
 124
 125 static int ssi_gdd_regs_open(struct inode *inode, struct file *file)
 126 {
 127         return single_open(file, ssi_debug_gdd_show, inode->i_private);
 128 }
 129
 130 static const struct file_operations ssi_regs_fops = {
 131         .open           = ssi_regs_open,
 132         .read           = seq_read,
 133         .llseek         = seq_lseek,
 134         .release        = single_release,
 135 };
 136
 137 static const struct file_operations ssi_gdd_regs_fops = {
 138         .open           = ssi_gdd_regs_open,
 139         .read           = seq_read,
 140         .llseek         = seq_lseek,
 141         .release        = single_release,
 142 };
 143
 144 static int ssi_debug_add_ctrl(struct hsi_controller *ssi)
 145 {
 146         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 147         struct dentry *dir;
 148
 149         /* SSI controller */
 150         omap_ssi->dir = debugfs_create_dir(dev_name(&ssi->device), NULL);
 151         if (!omap_ssi->dir)
 152                 return -ENOMEM;
 153
 154         debugfs_create_file("regs", S_IRUGO, omap_ssi->dir, ssi,
 155                                                                 &ssi_regs_fops);
 156         /* SSI GDD (DMA) */
 157         dir = debugfs_create_dir("gdd", omap_ssi->dir);
 158         if (!dir)
 159                 goto rback;
 160         debugfs_create_file("regs", S_IRUGO, dir, ssi, &ssi_gdd_regs_fops);
 161
 162         return 0;
 163 rback:
 164         debugfs_remove_recursive(omap_ssi->dir);
 165
 166         return -ENOMEM;
 167 }
 168
 169 static void ssi_debug_remove_ctrl(struct hsi_controller *ssi)
 170 {
 171         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 172
 173         debugfs_remove_recursive(omap_ssi->dir);
 174 }
 175 #endif /* CONFIG_DEBUG_FS */
 176
 177 /*
 178  * FIXME: Horrible HACK needed until we remove the useless wakeline test
 179  * in the CMT. To be removed !!!!
 180  */
 181 void ssi_waketest(struct hsi_client *cl, unsigned int enable)
 182 {
 183         struct hsi_port *port = hsi_get_port(cl);
 184         struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
 185         struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
 186         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 187
 188         omap_port->wktest = !!enable;
 189         if (omap_port->wktest) {
 190                 pm_runtime_get_sync(ssi->device.parent);
 191                 writel_relaxed(SSI_WAKE(0),
 192                                 omap_ssi->sys + SSI_SET_WAKE_REG(port->num));
 193         } else {
 194                 writel_relaxed(SSI_WAKE(0),
 195                                 omap_ssi->sys + SSI_CLEAR_WAKE_REG(port->num));
 196                 pm_runtime_put(ssi->device.parent);
 197         }
 198 }
 199 EXPORT_SYMBOL_GPL(ssi_waketest);
 200
 201 static void ssi_gdd_complete(struct hsi_controller *ssi, unsigned int lch)
 202 {
 203         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 204         struct hsi_msg *msg = omap_ssi->gdd_trn[lch].msg;
 205         struct hsi_port *port = to_hsi_port(msg->cl->device.parent);
 206         struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
 207         unsigned int dir;
 208         u32 csr;
 209         u32 val;
 210
 211         spin_lock(&omap_ssi->lock);
 212
 213         val = readl(omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
 214         val &= ~SSI_GDD_LCH(lch);
 215         writel_relaxed(val, omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
 216
 217         if (msg->ttype == HSI_MSG_READ) {
 218                 dir = DMA_FROM_DEVICE;
 219                 val = SSI_DATAAVAILABLE(msg->channel);
 220                 pm_runtime_put(omap_port->pdev);
 221         } else {
 222                 dir = DMA_TO_DEVICE;
 223                 val = SSI_DATAACCEPT(msg->channel);
 224                 /* Keep clocks reference for write pio event */
 225         }
 226         dma_unmap_sg(&ssi->device, msg->sgt.sgl, msg->sgt.nents, dir);
 227         csr = readw(omap_ssi->gdd + SSI_GDD_CSR_REG(lch));
 228         omap_ssi->gdd_trn[lch].msg = NULL; /* release GDD lch */
 229         dev_dbg(&port->device, "DMA completed ch %d ttype %d\n",
 230                                 msg->channel, msg->ttype);
 231         spin_unlock(&omap_ssi->lock);
 232         if (csr & SSI_CSR_TOUR) { /* Timeout error */
 233                 msg->status = HSI_STATUS_ERROR;
 234                 msg->actual_len = 0;
 235                 spin_lock(&omap_port->lock);
 236                 list_del(&msg->link); /* Dequeue msg */
 237                 spin_unlock(&omap_port->lock);
 238
 239                 list_add_tail(&msg->link, &omap_port->errqueue);
 240                 schedule_delayed_work(&omap_port->errqueue_work, 0);
 241                 return;
 242         }
 243         spin_lock(&omap_port->lock);
 244         val |= readl(omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
 245         writel_relaxed(val, omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
 246         spin_unlock(&omap_port->lock);
 247
 248         msg->status = HSI_STATUS_COMPLETED;
 249         msg->actual_len = sg_dma_len(msg->sgt.sgl);
 250 }
 251
 252 static void ssi_gdd_tasklet(unsigned long dev)
 253 {
 254         struct hsi_controller *ssi = (struct hsi_controller *)dev;
 255         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 256         void __iomem *sys = omap_ssi->sys;
 257         unsigned int lch;
 258         u32 status_reg;
 259
 260         pm_runtime_get(ssi->device.parent);
 261
 262         if (!pm_runtime_active(ssi->device.parent)) {
 263                 dev_warn(ssi->device.parent, "ssi_gdd_tasklet called without runtime PM!\n");
 264                 pm_runtime_put(ssi->device.parent);
 265                 return;
 266         }
 267
 268         status_reg = readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG);
 269         for (lch = 0; lch < SSI_MAX_GDD_LCH; lch++) {
 270                 if (status_reg & SSI_GDD_LCH(lch))
 271                         ssi_gdd_complete(ssi, lch);
 272         }
 273         writel_relaxed(status_reg, sys + SSI_GDD_MPU_IRQ_STATUS_REG);
 274         status_reg = readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG);
 275
 276         pm_runtime_put(ssi->device.parent);
 277
 278         if (status_reg)
 279                 tasklet_hi_schedule(&omap_ssi->gdd_tasklet);
 280         else
 281                 enable_irq(omap_ssi->gdd_irq);
 282
 283 }
 284
 285 static irqreturn_t ssi_gdd_isr(int irq, void *ssi)
 286 {
 287         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 288
 289         tasklet_hi_schedule(&omap_ssi->gdd_tasklet);
 290         disable_irq_nosync(irq);
 291
 292         return IRQ_HANDLED;
 293 }
 294
 295 static unsigned long ssi_get_clk_rate(struct hsi_controller *ssi)
 296 {
 297         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 298         unsigned long rate = clk_get_rate(omap_ssi->fck);
 299         return rate;
 300 }
 301
 302 static int ssi_clk_event(struct notifier_block *nb, unsigned long event,
 303                                                                 void *data)
 304 {
 305         struct omap_ssi_controller *omap_ssi = container_of(nb,
 306                                         struct omap_ssi_controller, fck_nb);
 307         struct hsi_controller *ssi = to_hsi_controller(omap_ssi->dev);
 308         struct clk_notifier_data *clk_data = data;
 309         struct omap_ssi_port *omap_port;
 310         int i;
 311
 312         switch (event) {
 313         case PRE_RATE_CHANGE:
 314                 dev_dbg(&ssi->device, "pre rate change\n");
 315
 316                 for (i = 0; i < ssi->num_ports; i++) {
 317                         omap_port = omap_ssi->port[i];
 318
 319                         if (!omap_port)
 320                                 continue;
 321
 322                         /* Workaround for SWBREAK + CAwake down race in CMT */
 323                         disable_irq(omap_port->wake_irq);
 324
 325                         /* stop all ssi communication */
 326                         pinctrl_pm_select_idle_state(omap_port->pdev);
 327                         udelay(1); /* wait for racing frames */
 328                 }
 329
 330                 break;
 331         case ABORT_RATE_CHANGE:
 332                 dev_dbg(&ssi->device, "abort rate change\n");
 333                 /* Fall through */
 334         case POST_RATE_CHANGE:
 335                 dev_dbg(&ssi->device, "post rate change (%lu -> %lu)\n",
 336                         clk_data->old_rate, clk_data->new_rate);
 337                 omap_ssi->fck_rate = DIV_ROUND_CLOSEST(clk_data->new_rate, 1000); /* kHz */
 338
 339                 for (i = 0; i < ssi->num_ports; i++) {
 340                         omap_port = omap_ssi->port[i];
 341
 342                         if (!omap_port)
 343                                 continue;
 344
 345                         omap_ssi_port_update_fclk(ssi, omap_port);
 346
 347                         /* resume ssi communication */
 348                         pinctrl_pm_select_default_state(omap_port->pdev);
 349                         enable_irq(omap_port->wake_irq);
 350                 }
 351
 352                 break;
 353         default:
 354                 break;
 355         }
 356
 357         return NOTIFY_DONE;
 358 }
 359
 360 static int ssi_get_iomem(struct platform_device *pd,
 361                 const char *name, void __iomem **pbase, dma_addr_t *phy)
 362 {
 363         struct resource *mem;
 364         void __iomem *base;
 365         struct hsi_controller *ssi = platform_get_drvdata(pd);
 366
 367         mem = platform_get_resource_byname(pd, IORESOURCE_MEM, name);
 368         base = devm_ioremap_resource(&ssi->device, mem);
 369         if (IS_ERR(base))
 370                 return PTR_ERR(base);
 371
 372         *pbase = base;
 373
 374         if (phy)
 375                 *phy = mem->start;
 376
 377         return 0;
 378 }
 379
 380 static int ssi_add_controller(struct hsi_controller *ssi,
 381                                                 struct platform_device *pd)
 382 {
 383         struct omap_ssi_controller *omap_ssi;
 384         int err;
 385
 386         omap_ssi = devm_kzalloc(&ssi->device, sizeof(*omap_ssi), GFP_KERNEL);
 387         if (!omap_ssi)
 388                 return -ENOMEM;
 389
 390         err = ida_simple_get(&platform_omap_ssi_ida, 0, 0, GFP_KERNEL);
 391         if (err < 0)
 392                 goto out_err;
 393         ssi->id = err;
 394
 395         ssi->owner = THIS_MODULE;
 396         ssi->device.parent = &pd->dev;
 397         dev_set_name(&ssi->device, "ssi%d", ssi->id);
 398         hsi_controller_set_drvdata(ssi, omap_ssi);
 399         omap_ssi->dev = &ssi->device;
 400         err = ssi_get_iomem(pd, "sys", &omap_ssi->sys, NULL);
 401         if (err < 0)
 402                 goto out_err;
 403         err = ssi_get_iomem(pd, "gdd", &omap_ssi->gdd, NULL);
 404         if (err < 0)
 405                 goto out_err;
 406         err = platform_get_irq_byname(pd, "gdd_mpu");
 407         if (err < 0) {
 408                 dev_err(&pd->dev, "GDD IRQ resource missing\n");
 409                 goto out_err;
 410         }
 411         omap_ssi->gdd_irq = err;
 412         tasklet_init(&omap_ssi->gdd_tasklet, ssi_gdd_tasklet,
 413                                                         (unsigned long)ssi);
 414         err = devm_request_irq(&ssi->device, omap_ssi->gdd_irq, ssi_gdd_isr,
 415                                                 0, "gdd_mpu", ssi);
 416         if (err < 0) {
 417                 dev_err(&ssi->device, "Request GDD IRQ %d failed (%d)",
 418                                                         omap_ssi->gdd_irq, err);
 419                 goto out_err;
 420         }
 421
 422         omap_ssi->port = devm_kcalloc(&ssi->device, ssi->num_ports,
 423                                       sizeof(*omap_ssi->port), GFP_KERNEL);
 424         if (!omap_ssi->port) {
 425                 err = -ENOMEM;
 426                 goto out_err;
 427         }
 428
 429         omap_ssi->fck = devm_clk_get(&ssi->device, "ssi_ssr_fck");
 430         if (IS_ERR(omap_ssi->fck)) {
 431                 dev_err(&pd->dev, "Could not acquire clock \"ssi_ssr_fck\": %li\n",
 432                         PTR_ERR(omap_ssi->fck));
 433                 err = -ENODEV;
 434                 goto out_err;
 435         }
 436
 437         omap_ssi->fck_nb.notifier_call = ssi_clk_event;
 438         omap_ssi->fck_nb.priority = INT_MAX;
 439         clk_notifier_register(omap_ssi->fck, &omap_ssi->fck_nb);
 440
 441         /* TODO: find register, which can be used to detect context loss */
 442         omap_ssi->get_loss = NULL;
 443
 444         omap_ssi->max_speed = UINT_MAX;
 445         spin_lock_init(&omap_ssi->lock);
 446         err = hsi_register_controller(ssi);
 447
 448         if (err < 0)
 449                 goto out_err;
 450
 451         return 0;
 452
 453 out_err:
 454         ida_simple_remove(&platform_omap_ssi_ida, ssi->id);
 455         return err;
 456 }
 457
 458 static int ssi_hw_init(struct hsi_controller *ssi)
 459 {
 460         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 461         int err;
 462
 463         err = pm_runtime_get_sync(ssi->device.parent);
 464         if (err < 0) {
 465                 dev_err(&ssi->device, "runtime PM failed %d\n", err);
 466                 return err;
 467         }
 468         /* Resetting GDD */
 469         writel_relaxed(SSI_SWRESET, omap_ssi->gdd + SSI_GDD_GRST_REG);
 470         /* Get FCK rate in kHz */
 471         omap_ssi->fck_rate = DIV_ROUND_CLOSEST(ssi_get_clk_rate(ssi), 1000);
 472         dev_dbg(&ssi->device, "SSI fck rate %lu kHz\n", omap_ssi->fck_rate);
 473
 474         writel_relaxed(SSI_CLK_AUTOGATING_ON, omap_ssi->sys + SSI_GDD_GCR_REG);
 475         omap_ssi->gdd_gcr = SSI_CLK_AUTOGATING_ON;
 476         pm_runtime_put_sync(ssi->device.parent);
 477
 478         return 0;
 479 }
 480
 481 static void ssi_remove_controller(struct hsi_controller *ssi)
 482 {
 483         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 484         int id = ssi->id;
 485         tasklet_kill(&omap_ssi->gdd_tasklet);
 486         hsi_unregister_controller(ssi);
 487         clk_notifier_unregister(omap_ssi->fck, &omap_ssi->fck_nb);
 488         ida_simple_remove(&platform_omap_ssi_ida, id);
 489 }
 490
 491 static inline int ssi_of_get_available_ports_count(const struct device_node *np)
 492 {
 493         struct device_node *child;
 494         int num = 0;
 495
 496         for_each_available_child_of_node(np, child)
 497                 if (of_device_is_compatible(child, "ti,omap3-ssi-port"))
 498                         num++;
 499
 500         return num;
 501 }
 502
 503 static int ssi_remove_ports(struct device *dev, void *c)
 504 {
 505         struct platform_device *pdev = to_platform_device(dev);
 506
 507         if (!dev->of_node)
 508                 return 0;
 509
 510         of_node_clear_flag(dev->of_node, OF_POPULATED);
 511         of_device_unregister(pdev);
 512
 513         return 0;
 514 }
 515
 516 static int ssi_probe(struct platform_device *pd)
 517 {
 518         struct platform_device *childpdev;
 519         struct device_node *np = pd->dev.of_node;
 520         struct device_node *child;
 521         struct hsi_controller *ssi;
 522         int err;
 523         int num_ports;
 524
 525         if (!np) {
 526                 dev_err(&pd->dev, "missing device tree data\n");
 527                 return -EINVAL;
 528         }
 529
 530         num_ports = ssi_of_get_available_ports_count(np);
 531
 532         ssi = hsi_alloc_controller(num_ports, GFP_KERNEL);
 533         if (!ssi) {
 534                 dev_err(&pd->dev, "No memory for controller\n");
 535                 return -ENOMEM;
 536         }
 537
 538         platform_set_drvdata(pd, ssi);
 539
 540         err = ssi_add_controller(ssi, pd);
 541         if (err < 0)
 542                 goto out1;
 543
 544         pm_runtime_enable(&pd->dev);
 545
 546         err = ssi_hw_init(ssi);
 547         if (err < 0)
 548                 goto out2;
 549 #ifdef CONFIG_DEBUG_FS
 550         err = ssi_debug_add_ctrl(ssi);
 551         if (err < 0)
 552                 goto out2;
 553 #endif
 554
 555         for_each_available_child_of_node(np, child) {
 556                 if (!of_device_is_compatible(child, "ti,omap3-ssi-port"))
 557                         continue;
 558
 559                 childpdev = of_platform_device_create(child, NULL, &pd->dev);
 560                 if (!childpdev) {
 561                         err = -ENODEV;
 562                         dev_err(&pd->dev, "failed to create ssi controller port\n");
 563                         goto out3;
 564                 }
 565         }
 566
 567         dev_info(&pd->dev, "ssi controller %d initialized (%d ports)!\n",
 568                 ssi->id, num_ports);
 569         return err;
 570 out3:
 571         device_for_each_child(&pd->dev, NULL, ssi_remove_ports);
 572 out2:
 573         ssi_remove_controller(ssi);
 574 out1:
 575         platform_set_drvdata(pd, NULL);
 576         pm_runtime_disable(&pd->dev);
 577
 578         return err;
 579 }
 580
 581 static int ssi_remove(struct platform_device *pd)
 582 {
 583         struct hsi_controller *ssi = platform_get_drvdata(pd);
 584
 585         /* cleanup of of_platform_populate() call */
 586         device_for_each_child(&pd->dev, NULL, ssi_remove_ports);
 587
 588 #ifdef CONFIG_DEBUG_FS
 589         ssi_debug_remove_ctrl(ssi);
 590 #endif
 591         ssi_remove_controller(ssi);
 592         platform_set_drvdata(pd, NULL);
 593
 594         pm_runtime_disable(&pd->dev);
 595
 596         return 0;
 597 }
 598
 599 #ifdef CONFIG_PM
 600 static int omap_ssi_runtime_suspend(struct device *dev)
 601 {
 602         struct hsi_controller *ssi = dev_get_drvdata(dev);
 603         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 604
 605         dev_dbg(dev, "runtime suspend!\n");
 606
 607         if (omap_ssi->get_loss)
 608                 omap_ssi->loss_count =
 609                                 omap_ssi->get_loss(ssi->device.parent);
 610
 611         return 0;
 612 }
 613
 614 static int omap_ssi_runtime_resume(struct device *dev)
 615 {
 616         struct hsi_controller *ssi = dev_get_drvdata(dev);
 617         struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 618
 619         dev_dbg(dev, "runtime resume!\n");
 620
 621         if ((omap_ssi->get_loss) && (omap_ssi->loss_count ==
 622                                 omap_ssi->get_loss(ssi->device.parent)))
 623                 return 0;
 624
 625         writel_relaxed(omap_ssi->gdd_gcr, omap_ssi->gdd + SSI_GDD_GCR_REG);
 626
 627         return 0;
 628 }
 629
 630 static const struct dev_pm_ops omap_ssi_pm_ops = {
 631         SET_RUNTIME_PM_OPS(omap_ssi_runtime_suspend, omap_ssi_runtime_resume,
 632                 NULL)
 633 };
 634
 635 #define DEV_PM_OPS     (&omap_ssi_pm_ops)
 636 #else
 637 #define DEV_PM_OPS     NULL
 638 #endif
 639
 640 #ifdef CONFIG_OF
 641 static const struct of_device_id omap_ssi_of_match[] = {
 642         { .compatible = "ti,omap3-ssi", },
 643         {},
 644 };
 645 MODULE_DEVICE_TABLE(of, omap_ssi_of_match);
 646 #else
 647 #define omap_ssi_of_match NULL
 648 #endif
 649
 650 static struct platform_driver ssi_pdriver = {
 651         .probe = ssi_probe,
 652         .remove = ssi_remove,
 653         .driver = {
 654                 .name   = "omap_ssi",
 655                 .pm     = DEV_PM_OPS,
 656                 .of_match_table = omap_ssi_of_match,
 657         },
 658 };
 659
 660 static int __init ssi_init(void) {
 661         int ret;
 662
 663         ret = platform_driver_register(&ssi_pdriver);
 664         if (ret)
 665                 return ret;
 666
 667         return platform_driver_register(&ssi_port_pdriver);
 668 }
 669 module_init(ssi_init);
 670
 671 static void __exit ssi_exit(void) {
 672         platform_driver_unregister(&ssi_port_pdriver);
 673         platform_driver_unregister(&ssi_pdriver);
 674 }
 675 module_exit(ssi_exit);
 676
 677 MODULE_ALIAS("platform:omap_ssi");
 678 MODULE_AUTHOR("Carlos Chinea <carlos.chinea@nokia.com>");
 679 MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>");
 680 MODULE_DESCRIPTION("Synchronous Serial Interface Driver");
 681 MODULE_LICENSE("GPL v2");