sound/soc/omap/mcpdm.c

   1 /*
   2  * mcpdm.c  --  McPDM interface driver
   3  *
   4  * Author: Jorge Eduardo Candelaria <x0107209@ti.com>
   5  * Copyright (C) 2009 - Texas Instruments, Inc.
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * version 2 as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  19  * 02110-1301 USA
  20  *
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25 #include <linux/device.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/wait.h>
  28 #include <linux/slab.h>
  29 #include <linux/interrupt.h>
  30 #include <linux/err.h>
  31 #include <linux/clk.h>
  32 #include <linux/delay.h>
  33 #include <linux/io.h>
  34 #include <linux/irq.h>
  35
  36 #include "mcpdm.h"
  37
  38 static struct omap_mcpdm *mcpdm;
  39
  40 static inline void omap_mcpdm_write(u16 reg, u32 val)
  41 {
  42         __raw_writel(val, mcpdm->io_base + reg);
  43 }
  44
  45 static inline int omap_mcpdm_read(u16 reg)
  46 {
  47         return __raw_readl(mcpdm->io_base + reg);
  48 }
  49
  50 static void omap_mcpdm_reg_dump(void)
  51 {
  52         dev_dbg(mcpdm->dev, "***********************\n");
  53         dev_dbg(mcpdm->dev, "IRQSTATUS_RAW:  0x%04x\n",
  54                         omap_mcpdm_read(MCPDM_IRQSTATUS_RAW));
  55         dev_dbg(mcpdm->dev, "IRQSTATUS: 0x%04x\n",
  56                         omap_mcpdm_read(MCPDM_IRQSTATUS));
  57         dev_dbg(mcpdm->dev, "IRQENABLE_SET:  0x%04x\n",
  58                         omap_mcpdm_read(MCPDM_IRQENABLE_SET));
  59         dev_dbg(mcpdm->dev, "IRQENABLE_CLR:  0x%04x\n",
  60                         omap_mcpdm_read(MCPDM_IRQENABLE_CLR));
  61         dev_dbg(mcpdm->dev, "IRQWAKE_EN: 0x%04x\n",
  62                         omap_mcpdm_read(MCPDM_IRQWAKE_EN));
  63         dev_dbg(mcpdm->dev, "DMAENABLE_SET: 0x%04x\n",
  64                         omap_mcpdm_read(MCPDM_DMAENABLE_SET));
  65         dev_dbg(mcpdm->dev, "DMAENABLE_CLR:  0x%04x\n",
  66                         omap_mcpdm_read(MCPDM_DMAENABLE_CLR));
  67         dev_dbg(mcpdm->dev, "DMAWAKEEN: 0x%04x\n",
  68                         omap_mcpdm_read(MCPDM_DMAWAKEEN));
  69         dev_dbg(mcpdm->dev, "CTRL:      0x%04x\n",
  70                         omap_mcpdm_read(MCPDM_CTRL));
  71         dev_dbg(mcpdm->dev, "DN_DATA:  0x%04x\n",
  72                         omap_mcpdm_read(MCPDM_DN_DATA));
  73         dev_dbg(mcpdm->dev, "UP_DATA: 0x%04x\n",
  74                         omap_mcpdm_read(MCPDM_UP_DATA));
  75         dev_dbg(mcpdm->dev, "FIFO_CTRL_DN: 0x%04x\n",
  76                         omap_mcpdm_read(MCPDM_FIFO_CTRL_DN));
  77         dev_dbg(mcpdm->dev, "FIFO_CTRL_UP:  0x%04x\n",
  78                         omap_mcpdm_read(MCPDM_FIFO_CTRL_UP));
  79         dev_dbg(mcpdm->dev, "DN_OFFSET: 0x%04x\n",
  80                         omap_mcpdm_read(MCPDM_DN_OFFSET));
  81         dev_dbg(mcpdm->dev, "***********************\n");
  82 }
  83
  84 /*
  85  * Takes the McPDM module in and out of reset state.
  86  * Uplink and downlink can be reset individually.
  87  */
  88 static void omap_mcpdm_reset_capture(int reset)
  89 {
  90         int ctrl = omap_mcpdm_read(MCPDM_CTRL);
  91
  92         if (reset)
  93                 ctrl |= SW_UP_RST;
  94         else
  95                 ctrl &= ~SW_UP_RST;
  96
  97         omap_mcpdm_write(MCPDM_CTRL, ctrl);
  98 }
  99
 100 static void omap_mcpdm_reset_playback(int reset)
 101 {
 102         int ctrl = omap_mcpdm_read(MCPDM_CTRL);
 103
 104         if (reset)
 105                 ctrl |= SW_DN_RST;
 106         else
 107                 ctrl &= ~SW_DN_RST;
 108
 109         omap_mcpdm_write(MCPDM_CTRL, ctrl);
 110 }
 111
 112 /*
 113  * Enables the transfer through the PDM interface to/from the Phoenix
 114  * codec by enabling the corresponding UP or DN channels.
 115  */
 116 void omap_mcpdm_start(int stream)
 117 {
 118         int ctrl = omap_mcpdm_read(MCPDM_CTRL);
 119
 120         if (stream)
 121                 ctrl |= mcpdm->up_channels;
 122         else
 123                 ctrl |= mcpdm->dn_channels;
 124
 125         omap_mcpdm_write(MCPDM_CTRL, ctrl);
 126 }
 127
 128 /*
 129  * Disables the transfer through the PDM interface to/from the Phoenix
 130  * codec by disabling the corresponding UP or DN channels.
 131  */
 132 void omap_mcpdm_stop(int stream)
 133 {
 134         int ctrl = omap_mcpdm_read(MCPDM_CTRL);
 135
 136         if (stream)
 137                 ctrl &= ~mcpdm->up_channels;
 138         else
 139                 ctrl &= ~mcpdm->dn_channels;
 140
 141         omap_mcpdm_write(MCPDM_CTRL, ctrl);
 142 }
 143
 144 /*
 145  * Configures McPDM uplink for audio recording.
 146  * This function should be called before omap_mcpdm_start.
 147  */
 148 int omap_mcpdm_capture_open(struct omap_mcpdm_link *uplink)
 149 {
 150         int irq_mask = 0;
 151         int ctrl;
 152
 153         if (!uplink)
 154                 return -EINVAL;
 155
 156         mcpdm->uplink = uplink;
 157
 158         /* Enable irq request generation */
 159         irq_mask |= uplink->irq_mask & MCPDM_UPLINK_IRQ_MASK;
 160         omap_mcpdm_write(MCPDM_IRQENABLE_SET, irq_mask);
 161
 162         /* Configure uplink threshold */
 163         if (uplink->threshold > UP_THRES_MAX)
 164                 uplink->threshold = UP_THRES_MAX;
 165
 166         omap_mcpdm_write(MCPDM_FIFO_CTRL_UP, uplink->threshold);
 167
 168         /* Configure DMA controller */
 169         omap_mcpdm_write(MCPDM_DMAENABLE_SET, DMA_UP_ENABLE);
 170
 171         /* Set pdm out format */
 172         ctrl = omap_mcpdm_read(MCPDM_CTRL);
 173         ctrl &= ~PDMOUTFORMAT;
 174         ctrl |= uplink->format & PDMOUTFORMAT;
 175
 176         /* Uplink channels */
 177         mcpdm->up_channels = uplink->channels & (PDM_UP_MASK | PDM_STATUS_MASK);
 178
 179         omap_mcpdm_write(MCPDM_CTRL, ctrl);
 180
 181         return 0;
 182 }
 183
 184 /*
 185  * Configures McPDM downlink for audio playback.
 186  * This function should be called before omap_mcpdm_start.
 187  */
 188 int omap_mcpdm_playback_open(struct omap_mcpdm_link *downlink)
 189 {
 190         int irq_mask = 0;
 191         int ctrl;
 192
 193         if (!downlink)
 194                 return -EINVAL;
 195
 196         mcpdm->downlink = downlink;
 197
 198         /* Enable irq request generation */
 199         irq_mask |= downlink->irq_mask & MCPDM_DOWNLINK_IRQ_MASK;
 200         omap_mcpdm_write(MCPDM_IRQENABLE_SET, irq_mask);
 201
 202         /* Configure uplink threshold */
 203         if (downlink->threshold > DN_THRES_MAX)
 204                 downlink->threshold = DN_THRES_MAX;
 205
 206         omap_mcpdm_write(MCPDM_FIFO_CTRL_DN, downlink->threshold);
 207
 208         /* Enable DMA request generation */
 209         omap_mcpdm_write(MCPDM_DMAENABLE_SET, DMA_DN_ENABLE);
 210
 211         /* Set pdm out format */
 212         ctrl = omap_mcpdm_read(MCPDM_CTRL);
 213         ctrl &= ~PDMOUTFORMAT;
 214         ctrl |= downlink->format & PDMOUTFORMAT;
 215
 216         /* Downlink channels */
 217         mcpdm->dn_channels = downlink->channels & (PDM_DN_MASK | PDM_CMD_MASK);
 218
 219         omap_mcpdm_write(MCPDM_CTRL, ctrl);
 220
 221         return 0;
 222 }
 223
 224 /*
 225  * Cleans McPDM uplink configuration.
 226  * This function should be called when the stream is closed.
 227  */
 228 int omap_mcpdm_capture_close(struct omap_mcpdm_link *uplink)
 229 {
 230         int irq_mask = 0;
 231
 232         if (!uplink)
 233                 return -EINVAL;
 234
 235         /* Disable irq request generation */
 236         irq_mask |= uplink->irq_mask & MCPDM_UPLINK_IRQ_MASK;
 237         omap_mcpdm_write(MCPDM_IRQENABLE_CLR, irq_mask);
 238
 239         /* Disable DMA request generation */
 240         omap_mcpdm_write(MCPDM_DMAENABLE_CLR, DMA_UP_ENABLE);
 241
 242         /* Clear Downlink channels */
 243         mcpdm->up_channels = 0;
 244
 245         mcpdm->uplink = NULL;
 246
 247         return 0;
 248 }
 249
 250 /*
 251  * Cleans McPDM downlink configuration.
 252  * This function should be called when the stream is closed.
 253  */
 254 int omap_mcpdm_playback_close(struct omap_mcpdm_link *downlink)
 255 {
 256         int irq_mask = 0;
 257
 258         if (!downlink)
 259                 return -EINVAL;
 260
 261         /* Disable irq request generation */
 262         irq_mask |= downlink->irq_mask & MCPDM_DOWNLINK_IRQ_MASK;
 263         omap_mcpdm_write(MCPDM_IRQENABLE_CLR, irq_mask);
 264
 265         /* Disable DMA request generation */
 266         omap_mcpdm_write(MCPDM_DMAENABLE_CLR, DMA_DN_ENABLE);
 267
 268         /* clear Downlink channels */
 269         mcpdm->dn_channels = 0;
 270
 271         mcpdm->downlink = NULL;
 272
 273         return 0;
 274 }
 275
 276 static irqreturn_t omap_mcpdm_irq_handler(int irq, void *dev_id)
 277 {
 278         struct omap_mcpdm *mcpdm_irq = dev_id;
 279         int irq_status;
 280
 281         irq_status = omap_mcpdm_read(MCPDM_IRQSTATUS);
 282
 283         /* Acknowledge irq event */
 284         omap_mcpdm_write(MCPDM_IRQSTATUS, irq_status);
 285
 286         if (irq & MCPDM_DN_IRQ_FULL) {
 287                 dev_err(mcpdm_irq->dev, "DN FIFO error %x\n", irq_status);
 288                 omap_mcpdm_reset_playback(1);
 289                 omap_mcpdm_playback_open(mcpdm_irq->downlink);
 290                 omap_mcpdm_reset_playback(0);
 291         }
 292
 293         if (irq & MCPDM_DN_IRQ_EMPTY) {
 294                 dev_err(mcpdm_irq->dev, "DN FIFO error %x\n", irq_status);
 295                 omap_mcpdm_reset_playback(1);
 296                 omap_mcpdm_playback_open(mcpdm_irq->downlink);
 297                 omap_mcpdm_reset_playback(0);
 298         }
 299
 300         if (irq & MCPDM_DN_IRQ) {
 301                 dev_dbg(mcpdm_irq->dev, "DN write request\n");
 302         }
 303
 304         if (irq & MCPDM_UP_IRQ_FULL) {
 305                 dev_err(mcpdm_irq->dev, "UP FIFO error %x\n", irq_status);
 306                 omap_mcpdm_reset_capture(1);
 307                 omap_mcpdm_capture_open(mcpdm_irq->uplink);
 308                 omap_mcpdm_reset_capture(0);
 309         }
 310
 311         if (irq & MCPDM_UP_IRQ_EMPTY) {
 312                 dev_err(mcpdm_irq->dev, "UP FIFO error %x\n", irq_status);
 313                 omap_mcpdm_reset_capture(1);
 314                 omap_mcpdm_capture_open(mcpdm_irq->uplink);
 315                 omap_mcpdm_reset_capture(0);
 316         }
 317
 318         if (irq & MCPDM_UP_IRQ) {
 319                 dev_dbg(mcpdm_irq->dev, "UP write request\n");
 320         }
 321
 322         return IRQ_HANDLED;
 323 }
 324
 325 int omap_mcpdm_request(void)
 326 {
 327         int ret;
 328
 329         clk_enable(mcpdm->clk);
 330
 331         spin_lock(&mcpdm->lock);
 332
 333         if (!mcpdm->free) {
 334                 dev_err(mcpdm->dev, "McPDM interface is in use\n");
 335                 spin_unlock(&mcpdm->lock);
 336                 ret = -EBUSY;
 337                 goto err;
 338         }
 339         mcpdm->free = 0;
 340
 341         spin_unlock(&mcpdm->lock);
 342
 343         /* Disable lines while request is ongoing */
 344         omap_mcpdm_write(MCPDM_CTRL, 0x00);
 345
 346         ret = request_irq(mcpdm->irq, omap_mcpdm_irq_handler,
 347                                 0, "McPDM", (void *)mcpdm);
 348         if (ret) {
 349                 dev_err(mcpdm->dev, "Request for McPDM IRQ failed\n");
 350                 goto err;
 351         }
 352
 353         return 0;
 354
 355 err:
 356         clk_disable(mcpdm->clk);
 357         return ret;
 358 }
 359
 360 void omap_mcpdm_free(void)
 361 {
 362         spin_lock(&mcpdm->lock);
 363         if (mcpdm->free) {
 364                 dev_err(mcpdm->dev, "McPDM interface is already free\n");
 365                 spin_unlock(&mcpdm->lock);
 366                 return;
 367         }
 368         mcpdm->free = 1;
 369         spin_unlock(&mcpdm->lock);
 370
 371         clk_disable(mcpdm->clk);
 372
 373         free_irq(mcpdm->irq, (void *)mcpdm);
 374 }
 375
 376 /* Enable/disable DC offset cancelation for the analog
 377  * headset path (PDM channels 1 and 2).
 378  */
 379 int omap_mcpdm_set_offset(int offset1, int offset2)
 380 {
 381         int offset;
 382
 383         if ((offset1 > DN_OFST_MAX) || (offset2 > DN_OFST_MAX))
 384                 return -EINVAL;
 385
 386         offset = (offset1 << DN_OFST_RX1) | (offset2 << DN_OFST_RX2);
 387
 388         /* offset cancellation for channel 1 */
 389         if (offset1)
 390                 offset |= DN_OFST_RX1_EN;
 391         else
 392                 offset &= ~DN_OFST_RX1_EN;
 393
 394         /* offset cancellation for channel 2 */
 395         if (offset2)
 396                 offset |= DN_OFST_RX2_EN;
 397         else
 398                 offset &= ~DN_OFST_RX2_EN;
 399
 400         omap_mcpdm_write(MCPDM_DN_OFFSET, offset);
 401
 402         return 0;
 403 }
 404
 405 static int __devinit omap_mcpdm_probe(struct platform_device *pdev)
 406 {
 407         struct resource *res;
 408         int ret = 0;
 409
 410         mcpdm = kzalloc(sizeof(struct omap_mcpdm), GFP_KERNEL);
 411         if (!mcpdm) {
 412                 ret = -ENOMEM;
 413                 goto exit;
 414         }
 415
 416         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 417         if (res == NULL) {
 418                 dev_err(&pdev->dev, "no resource\n");
 419                 goto err_resource;
 420         }
 421
 422         spin_lock_init(&mcpdm->lock);
 423         mcpdm->free = 1;
 424         mcpdm->io_base = ioremap(res->start, resource_size(res));
 425         if (!mcpdm->io_base) {
 426                 ret = -ENOMEM;
 427                 goto err_resource;
 428         }
 429
 430         mcpdm->irq = platform_get_irq(pdev, 0);
 431
 432         mcpdm->clk = clk_get(&pdev->dev, "pdm_ck");
 433         if (IS_ERR(mcpdm->clk)) {
 434                 ret = PTR_ERR(mcpdm->clk);
 435                 dev_err(&pdev->dev, "unable to get pdm_ck: %d\n", ret);
 436                 goto err_clk;
 437         }
 438
 439         mcpdm->dev = &pdev->dev;
 440         platform_set_drvdata(pdev, mcpdm);
 441
 442         return 0;
 443
 444 err_clk:
 445         iounmap(mcpdm->io_base);
 446 err_resource:
 447         kfree(mcpdm);
 448 exit:
 449         return ret;
 450 }
 451
 452 static int __devexit omap_mcpdm_remove(struct platform_device *pdev)
 453 {
 454         struct omap_mcpdm *mcpdm_ptr = platform_get_drvdata(pdev);
 455
 456         platform_set_drvdata(pdev, NULL);
 457
 458         clk_put(mcpdm_ptr->clk);
 459
 460         iounmap(mcpdm_ptr->io_base);
 461
 462         mcpdm_ptr->clk = NULL;
 463         mcpdm_ptr->free = 0;
 464         mcpdm_ptr->dev = NULL;
 465
 466         kfree(mcpdm_ptr);
 467
 468         return 0;
 469 }
 470
 471 static struct platform_driver omap_mcpdm_driver = {
 472         .probe = omap_mcpdm_probe,
 473         .remove = __devexit_p(omap_mcpdm_remove),
 474         .driver = {
 475                 .name = "omap-mcpdm",
 476         },
 477 };
 478
 479 static struct platform_device *omap_mcpdm_device;
 480
 481 static int __init omap_mcpdm_init(void)
 482 {
 483         return platform_driver_register(&omap_mcpdm_driver);
 484 }
 485 arch_initcall(omap_mcpdm_init);