LXR linux/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
  38static struct omap_mcpdm *mcpdm;
  39
  40static inline void omap_mcpdm_write(u16 reg, u32 val)
  41{
  42        __raw_writel(val, mcpdm->io_base + reg);
  43}
  44
  45static inline int omap_mcpdm_read(u16 reg)
  46{
  47        return __raw_readl(mcpdm->io_base + reg);
  48}
  49
  50static 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 */
  88static 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
 100static 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 */
 116void 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 */
 132void 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 */
 148int 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 */
 188int 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 */
 228int 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 */
 254int 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
 276static 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
 325int 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
 355err:
 356        clk_disable(mcpdm->clk);
 357        return ret;
 358}
 359
 360void 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 */
 379int 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
 405int __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
 444err_clk:
 445        iounmap(mcpdm->io_base);
 446err_resource:
 447        kfree(mcpdm);
 448exit:
 449        return ret;
 450}
 451
 452int 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