linux/drivers/dma/imx-dma.c
<<
>>
Prefs
   1/*
   2 * drivers/dma/imx-dma.c
   3 *
   4 * This file contains a driver for the Freescale i.MX DMA engine
   5 * found on i.MX1/21/27
   6 *
   7 * Copyright 2010 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
   8 * Copyright 2012 Javier Martin, Vista Silicon <javier.martin@vista-silicon.com>
   9 *
  10 * The code contained herein is licensed under the GNU General Public
  11 * License. You may obtain a copy of the GNU General Public License
  12 * Version 2 or later at the following locations:
  13 *
  14 * http://www.opensource.org/licenses/gpl-license.html
  15 * http://www.gnu.org/copyleft/gpl.html
  16 */
  17#include <linux/init.h>
  18#include <linux/types.h>
  19#include <linux/mm.h>
  20#include <linux/interrupt.h>
  21#include <linux/spinlock.h>
  22#include <linux/device.h>
  23#include <linux/dma-mapping.h>
  24#include <linux/slab.h>
  25#include <linux/platform_device.h>
  26#include <linux/clk.h>
  27#include <linux/dmaengine.h>
  28#include <linux/module.h>
  29
  30#include <asm/irq.h>
  31#include <mach/dma.h>
  32#include <mach/hardware.h>
  33
  34#include "dmaengine.h"
  35#define IMXDMA_MAX_CHAN_DESCRIPTORS     16
  36#define IMX_DMA_CHANNELS  16
  37
  38#define IMX_DMA_2D_SLOTS        2
  39#define IMX_DMA_2D_SLOT_A       0
  40#define IMX_DMA_2D_SLOT_B       1
  41
  42#define IMX_DMA_LENGTH_LOOP     ((unsigned int)-1)
  43#define IMX_DMA_MEMSIZE_32      (0 << 4)
  44#define IMX_DMA_MEMSIZE_8       (1 << 4)
  45#define IMX_DMA_MEMSIZE_16      (2 << 4)
  46#define IMX_DMA_TYPE_LINEAR     (0 << 10)
  47#define IMX_DMA_TYPE_2D         (1 << 10)
  48#define IMX_DMA_TYPE_FIFO       (2 << 10)
  49
  50#define IMX_DMA_ERR_BURST     (1 << 0)
  51#define IMX_DMA_ERR_REQUEST   (1 << 1)
  52#define IMX_DMA_ERR_TRANSFER  (1 << 2)
  53#define IMX_DMA_ERR_BUFFER    (1 << 3)
  54#define IMX_DMA_ERR_TIMEOUT   (1 << 4)
  55
  56#define DMA_DCR     0x00                /* Control Register */
  57#define DMA_DISR    0x04                /* Interrupt status Register */
  58#define DMA_DIMR    0x08                /* Interrupt mask Register */
  59#define DMA_DBTOSR  0x0c                /* Burst timeout status Register */
  60#define DMA_DRTOSR  0x10                /* Request timeout Register */
  61#define DMA_DSESR   0x14                /* Transfer Error Status Register */
  62#define DMA_DBOSR   0x18                /* Buffer overflow status Register */
  63#define DMA_DBTOCR  0x1c                /* Burst timeout control Register */
  64#define DMA_WSRA    0x40                /* W-Size Register A */
  65#define DMA_XSRA    0x44                /* X-Size Register A */
  66#define DMA_YSRA    0x48                /* Y-Size Register A */
  67#define DMA_WSRB    0x4c                /* W-Size Register B */
  68#define DMA_XSRB    0x50                /* X-Size Register B */
  69#define DMA_YSRB    0x54                /* Y-Size Register B */
  70#define DMA_SAR(x)  (0x80 + ((x) << 6)) /* Source Address Registers */
  71#define DMA_DAR(x)  (0x84 + ((x) << 6)) /* Destination Address Registers */
  72#define DMA_CNTR(x) (0x88 + ((x) << 6)) /* Count Registers */
  73#define DMA_CCR(x)  (0x8c + ((x) << 6)) /* Control Registers */
  74#define DMA_RSSR(x) (0x90 + ((x) << 6)) /* Request source select Registers */
  75#define DMA_BLR(x)  (0x94 + ((x) << 6)) /* Burst length Registers */
  76#define DMA_RTOR(x) (0x98 + ((x) << 6)) /* Request timeout Registers */
  77#define DMA_BUCR(x) (0x98 + ((x) << 6)) /* Bus Utilization Registers */
  78#define DMA_CCNR(x) (0x9C + ((x) << 6)) /* Channel counter Registers */
  79
  80#define DCR_DRST           (1<<1)
  81#define DCR_DEN            (1<<0)
  82#define DBTOCR_EN          (1<<15)
  83#define DBTOCR_CNT(x)      ((x) & 0x7fff)
  84#define CNTR_CNT(x)        ((x) & 0xffffff)
  85#define CCR_ACRPT          (1<<14)
  86#define CCR_DMOD_LINEAR    (0x0 << 12)
  87#define CCR_DMOD_2D        (0x1 << 12)
  88#define CCR_DMOD_FIFO      (0x2 << 12)
  89#define CCR_DMOD_EOBFIFO   (0x3 << 12)
  90#define CCR_SMOD_LINEAR    (0x0 << 10)
  91#define CCR_SMOD_2D        (0x1 << 10)
  92#define CCR_SMOD_FIFO      (0x2 << 10)
  93#define CCR_SMOD_EOBFIFO   (0x3 << 10)
  94#define CCR_MDIR_DEC       (1<<9)
  95#define CCR_MSEL_B         (1<<8)
  96#define CCR_DSIZ_32        (0x0 << 6)
  97#define CCR_DSIZ_8         (0x1 << 6)
  98#define CCR_DSIZ_16        (0x2 << 6)
  99#define CCR_SSIZ_32        (0x0 << 4)
 100#define CCR_SSIZ_8         (0x1 << 4)
 101#define CCR_SSIZ_16        (0x2 << 4)
 102#define CCR_REN            (1<<3)
 103#define CCR_RPT            (1<<2)
 104#define CCR_FRC            (1<<1)
 105#define CCR_CEN            (1<<0)
 106#define RTOR_EN            (1<<15)
 107#define RTOR_CLK           (1<<14)
 108#define RTOR_PSC           (1<<13)
 109
 110enum  imxdma_prep_type {
 111        IMXDMA_DESC_MEMCPY,
 112        IMXDMA_DESC_INTERLEAVED,
 113        IMXDMA_DESC_SLAVE_SG,
 114        IMXDMA_DESC_CYCLIC,
 115};
 116
 117struct imx_dma_2d_config {
 118        u16             xsr;
 119        u16             ysr;
 120        u16             wsr;
 121        int             count;
 122};
 123
 124struct imxdma_desc {
 125        struct list_head                node;
 126        struct dma_async_tx_descriptor  desc;
 127        enum dma_status                 status;
 128        dma_addr_t                      src;
 129        dma_addr_t                      dest;
 130        size_t                          len;
 131        enum dma_transfer_direction     direction;
 132        enum imxdma_prep_type           type;
 133        /* For memcpy and interleaved */
 134        unsigned int                    config_port;
 135        unsigned int                    config_mem;
 136        /* For interleaved transfers */
 137        unsigned int                    x;
 138        unsigned int                    y;
 139        unsigned int                    w;
 140        /* For slave sg and cyclic */
 141        struct scatterlist              *sg;
 142        unsigned int                    sgcount;
 143};
 144
 145struct imxdma_channel {
 146        int                             hw_chaining;
 147        struct timer_list               watchdog;
 148        struct imxdma_engine            *imxdma;
 149        unsigned int                    channel;
 150
 151        struct tasklet_struct           dma_tasklet;
 152        struct list_head                ld_free;
 153        struct list_head                ld_queue;
 154        struct list_head                ld_active;
 155        int                             descs_allocated;
 156        enum dma_slave_buswidth         word_size;
 157        dma_addr_t                      per_address;
 158        u32                             watermark_level;
 159        struct dma_chan                 chan;
 160        struct dma_async_tx_descriptor  desc;
 161        enum dma_status                 status;
 162        int                             dma_request;
 163        struct scatterlist              *sg_list;
 164        u32                             ccr_from_device;
 165        u32                             ccr_to_device;
 166        bool                            enabled_2d;
 167        int                             slot_2d;
 168};
 169
 170struct imxdma_engine {
 171        struct device                   *dev;
 172        struct device_dma_parameters    dma_parms;
 173        struct dma_device               dma_device;
 174        void __iomem                    *base;
 175        struct clk                      *dma_ahb;
 176        struct clk                      *dma_ipg;
 177        spinlock_t                      lock;
 178        struct imx_dma_2d_config        slots_2d[IMX_DMA_2D_SLOTS];
 179        struct imxdma_channel           channel[IMX_DMA_CHANNELS];
 180};
 181
 182static struct imxdma_channel *to_imxdma_chan(struct dma_chan *chan)
 183{
 184        return container_of(chan, struct imxdma_channel, chan);
 185}
 186
 187static inline bool imxdma_chan_is_doing_cyclic(struct imxdma_channel *imxdmac)
 188{
 189        struct imxdma_desc *desc;
 190
 191        if (!list_empty(&imxdmac->ld_active)) {
 192                desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc,
 193                                        node);
 194                if (desc->type == IMXDMA_DESC_CYCLIC)
 195                        return true;
 196        }
 197        return false;
 198}
 199
 200
 201
 202static void imx_dmav1_writel(struct imxdma_engine *imxdma, unsigned val,
 203                             unsigned offset)
 204{
 205        __raw_writel(val, imxdma->base + offset);
 206}
 207
 208static unsigned imx_dmav1_readl(struct imxdma_engine *imxdma, unsigned offset)
 209{
 210        return __raw_readl(imxdma->base + offset);
 211}
 212
 213static int imxdma_hw_chain(struct imxdma_channel *imxdmac)
 214{
 215        if (cpu_is_mx27())
 216                return imxdmac->hw_chaining;
 217        else
 218                return 0;
 219}
 220
 221/*
 222 * imxdma_sg_next - prepare next chunk for scatter-gather DMA emulation
 223 */
 224static inline int imxdma_sg_next(struct imxdma_desc *d)
 225{
 226        struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
 227        struct imxdma_engine *imxdma = imxdmac->imxdma;
 228        struct scatterlist *sg = d->sg;
 229        unsigned long now;
 230
 231        now = min(d->len, sg_dma_len(sg));
 232        if (d->len != IMX_DMA_LENGTH_LOOP)
 233                d->len -= now;
 234
 235        if (d->direction == DMA_DEV_TO_MEM)
 236                imx_dmav1_writel(imxdma, sg->dma_address,
 237                                 DMA_DAR(imxdmac->channel));
 238        else
 239                imx_dmav1_writel(imxdma, sg->dma_address,
 240                                 DMA_SAR(imxdmac->channel));
 241
 242        imx_dmav1_writel(imxdma, now, DMA_CNTR(imxdmac->channel));
 243
 244        dev_dbg(imxdma->dev, " %s channel: %d dst 0x%08x, src 0x%08x, "
 245                "size 0x%08x\n", __func__, imxdmac->channel,
 246                 imx_dmav1_readl(imxdma, DMA_DAR(imxdmac->channel)),
 247                 imx_dmav1_readl(imxdma, DMA_SAR(imxdmac->channel)),
 248                 imx_dmav1_readl(imxdma, DMA_CNTR(imxdmac->channel)));
 249
 250        return now;
 251}
 252
 253static void imxdma_enable_hw(struct imxdma_desc *d)
 254{
 255        struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
 256        struct imxdma_engine *imxdma = imxdmac->imxdma;
 257        int channel = imxdmac->channel;
 258        unsigned long flags;
 259
 260        dev_dbg(imxdma->dev, "%s channel %d\n", __func__, channel);
 261
 262        local_irq_save(flags);
 263
 264        imx_dmav1_writel(imxdma, 1 << channel, DMA_DISR);
 265        imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_DIMR) &
 266                         ~(1 << channel), DMA_DIMR);
 267        imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_CCR(channel)) |
 268                         CCR_CEN | CCR_ACRPT, DMA_CCR(channel));
 269
 270        if ((cpu_is_mx21() || cpu_is_mx27()) &&
 271                        d->sg && imxdma_hw_chain(imxdmac)) {
 272                d->sg = sg_next(d->sg);
 273                if (d->sg) {
 274                        u32 tmp;
 275                        imxdma_sg_next(d);
 276                        tmp = imx_dmav1_readl(imxdma, DMA_CCR(channel));
 277                        imx_dmav1_writel(imxdma, tmp | CCR_RPT | CCR_ACRPT,
 278                                         DMA_CCR(channel));
 279                }
 280        }
 281
 282        local_irq_restore(flags);
 283}
 284
 285static void imxdma_disable_hw(struct imxdma_channel *imxdmac)
 286{
 287        struct imxdma_engine *imxdma = imxdmac->imxdma;
 288        int channel = imxdmac->channel;
 289        unsigned long flags;
 290
 291        dev_dbg(imxdma->dev, "%s channel %d\n", __func__, channel);
 292
 293        if (imxdma_hw_chain(imxdmac))
 294                del_timer(&imxdmac->watchdog);
 295
 296        local_irq_save(flags);
 297        imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_DIMR) |
 298                         (1 << channel), DMA_DIMR);
 299        imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_CCR(channel)) &
 300                         ~CCR_CEN, DMA_CCR(channel));
 301        imx_dmav1_writel(imxdma, 1 << channel, DMA_DISR);
 302        local_irq_restore(flags);
 303}
 304
 305static void imxdma_watchdog(unsigned long data)
 306{
 307        struct imxdma_channel *imxdmac = (struct imxdma_channel *)data;
 308        struct imxdma_engine *imxdma = imxdmac->imxdma;
 309        int channel = imxdmac->channel;
 310
 311        imx_dmav1_writel(imxdma, 0, DMA_CCR(channel));
 312
 313        /* Tasklet watchdog error handler */
 314        tasklet_schedule(&imxdmac->dma_tasklet);
 315        dev_dbg(imxdma->dev, "channel %d: watchdog timeout!\n",
 316                imxdmac->channel);
 317}
 318
 319static irqreturn_t imxdma_err_handler(int irq, void *dev_id)
 320{
 321        struct imxdma_engine *imxdma = dev_id;
 322        unsigned int err_mask;
 323        int i, disr;
 324        int errcode;
 325
 326        disr = imx_dmav1_readl(imxdma, DMA_DISR);
 327
 328        err_mask = imx_dmav1_readl(imxdma, DMA_DBTOSR) |
 329                   imx_dmav1_readl(imxdma, DMA_DRTOSR) |
 330                   imx_dmav1_readl(imxdma, DMA_DSESR)  |
 331                   imx_dmav1_readl(imxdma, DMA_DBOSR);
 332
 333        if (!err_mask)
 334                return IRQ_HANDLED;
 335
 336        imx_dmav1_writel(imxdma, disr & err_mask, DMA_DISR);
 337
 338        for (i = 0; i < IMX_DMA_CHANNELS; i++) {
 339                if (!(err_mask & (1 << i)))
 340                        continue;
 341                errcode = 0;
 342
 343                if (imx_dmav1_readl(imxdma, DMA_DBTOSR) & (1 << i)) {
 344                        imx_dmav1_writel(imxdma, 1 << i, DMA_DBTOSR);
 345                        errcode |= IMX_DMA_ERR_BURST;
 346                }
 347                if (imx_dmav1_readl(imxdma, DMA_DRTOSR) & (1 << i)) {
 348                        imx_dmav1_writel(imxdma, 1 << i, DMA_DRTOSR);
 349                        errcode |= IMX_DMA_ERR_REQUEST;
 350                }
 351                if (imx_dmav1_readl(imxdma, DMA_DSESR) & (1 << i)) {
 352                        imx_dmav1_writel(imxdma, 1 << i, DMA_DSESR);
 353                        errcode |= IMX_DMA_ERR_TRANSFER;
 354                }
 355                if (imx_dmav1_readl(imxdma, DMA_DBOSR) & (1 << i)) {
 356                        imx_dmav1_writel(imxdma, 1 << i, DMA_DBOSR);
 357                        errcode |= IMX_DMA_ERR_BUFFER;
 358                }
 359                /* Tasklet error handler */
 360                tasklet_schedule(&imxdma->channel[i].dma_tasklet);
 361
 362                printk(KERN_WARNING
 363                       "DMA timeout on channel %d -%s%s%s%s\n", i,
 364                       errcode & IMX_DMA_ERR_BURST ?    " burst" : "",
 365                       errcode & IMX_DMA_ERR_REQUEST ?  " request" : "",
 366                       errcode & IMX_DMA_ERR_TRANSFER ? " transfer" : "",
 367                       errcode & IMX_DMA_ERR_BUFFER ?   " buffer" : "");
 368        }
 369        return IRQ_HANDLED;
 370}
 371
 372static void dma_irq_handle_channel(struct imxdma_channel *imxdmac)
 373{
 374        struct imxdma_engine *imxdma = imxdmac->imxdma;
 375        int chno = imxdmac->channel;
 376        struct imxdma_desc *desc;
 377
 378        spin_lock(&imxdma->lock);
 379        if (list_empty(&imxdmac->ld_active)) {
 380                spin_unlock(&imxdma->lock);
 381                goto out;
 382        }
 383
 384        desc = list_first_entry(&imxdmac->ld_active,
 385                                struct imxdma_desc,
 386                                node);
 387        spin_unlock(&imxdma->lock);
 388
 389        if (desc->sg) {
 390                u32 tmp;
 391                desc->sg = sg_next(desc->sg);
 392
 393                if (desc->sg) {
 394                        imxdma_sg_next(desc);
 395
 396                        tmp = imx_dmav1_readl(imxdma, DMA_CCR(chno));
 397
 398                        if (imxdma_hw_chain(imxdmac)) {
 399                                /* FIXME: The timeout should probably be
 400                                 * configurable
 401                                 */
 402                                mod_timer(&imxdmac->watchdog,
 403                                        jiffies + msecs_to_jiffies(500));
 404
 405                                tmp |= CCR_CEN | CCR_RPT | CCR_ACRPT;
 406                                imx_dmav1_writel(imxdma, tmp, DMA_CCR(chno));
 407                        } else {
 408                                imx_dmav1_writel(imxdma, tmp & ~CCR_CEN,
 409                                                 DMA_CCR(chno));
 410                                tmp |= CCR_CEN;
 411                        }
 412
 413                        imx_dmav1_writel(imxdma, tmp, DMA_CCR(chno));
 414
 415                        if (imxdma_chan_is_doing_cyclic(imxdmac))
 416                                /* Tasklet progression */
 417                                tasklet_schedule(&imxdmac->dma_tasklet);
 418
 419                        return;
 420                }
 421
 422                if (imxdma_hw_chain(imxdmac)) {
 423                        del_timer(&imxdmac->watchdog);
 424                        return;
 425                }
 426        }
 427
 428out:
 429        imx_dmav1_writel(imxdma, 0, DMA_CCR(chno));
 430        /* Tasklet irq */
 431        tasklet_schedule(&imxdmac->dma_tasklet);
 432}
 433
 434static irqreturn_t dma_irq_handler(int irq, void *dev_id)
 435{
 436        struct imxdma_engine *imxdma = dev_id;
 437        int i, disr;
 438
 439        if (cpu_is_mx21() || cpu_is_mx27())
 440                imxdma_err_handler(irq, dev_id);
 441
 442        disr = imx_dmav1_readl(imxdma, DMA_DISR);
 443
 444        dev_dbg(imxdma->dev, "%s called, disr=0x%08x\n", __func__, disr);
 445
 446        imx_dmav1_writel(imxdma, disr, DMA_DISR);
 447        for (i = 0; i < IMX_DMA_CHANNELS; i++) {
 448                if (disr & (1 << i))
 449                        dma_irq_handle_channel(&imxdma->channel[i]);
 450        }
 451
 452        return IRQ_HANDLED;
 453}
 454
 455static int imxdma_xfer_desc(struct imxdma_desc *d)
 456{
 457        struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
 458        struct imxdma_engine *imxdma = imxdmac->imxdma;
 459        unsigned long flags;
 460        int slot = -1;
 461        int i;
 462
 463        /* Configure and enable */
 464        switch (d->type) {
 465        case IMXDMA_DESC_INTERLEAVED:
 466                /* Try to get a free 2D slot */
 467                spin_lock_irqsave(&imxdma->lock, flags);
 468                for (i = 0; i < IMX_DMA_2D_SLOTS; i++) {
 469                        if ((imxdma->slots_2d[i].count > 0) &&
 470                        ((imxdma->slots_2d[i].xsr != d->x) ||
 471                        (imxdma->slots_2d[i].ysr != d->y) ||
 472                        (imxdma->slots_2d[i].wsr != d->w)))
 473                                continue;
 474                        slot = i;
 475                        break;
 476                }
 477                if (slot < 0) {
 478                        spin_unlock_irqrestore(&imxdma->lock, flags);
 479                        return -EBUSY;
 480                }
 481
 482                imxdma->slots_2d[slot].xsr = d->x;
 483                imxdma->slots_2d[slot].ysr = d->y;
 484                imxdma->slots_2d[slot].wsr = d->w;
 485                imxdma->slots_2d[slot].count++;
 486
 487                imxdmac->slot_2d = slot;
 488                imxdmac->enabled_2d = true;
 489                spin_unlock_irqrestore(&imxdma->lock, flags);
 490
 491                if (slot == IMX_DMA_2D_SLOT_A) {
 492                        d->config_mem &= ~CCR_MSEL_B;
 493                        d->config_port &= ~CCR_MSEL_B;
 494                        imx_dmav1_writel(imxdma, d->x, DMA_XSRA);
 495                        imx_dmav1_writel(imxdma, d->y, DMA_YSRA);
 496                        imx_dmav1_writel(imxdma, d->w, DMA_WSRA);
 497                } else {
 498                        d->config_mem |= CCR_MSEL_B;
 499                        d->config_port |= CCR_MSEL_B;
 500                        imx_dmav1_writel(imxdma, d->x, DMA_XSRB);
 501                        imx_dmav1_writel(imxdma, d->y, DMA_YSRB);
 502                        imx_dmav1_writel(imxdma, d->w, DMA_WSRB);
 503                }
 504                /*
 505                 * We fall-through here intentionally, since a 2D transfer is
 506                 * similar to MEMCPY just adding the 2D slot configuration.
 507                 */
 508        case IMXDMA_DESC_MEMCPY:
 509                imx_dmav1_writel(imxdma, d->src, DMA_SAR(imxdmac->channel));
 510                imx_dmav1_writel(imxdma, d->dest, DMA_DAR(imxdmac->channel));
 511                imx_dmav1_writel(imxdma, d->config_mem | (d->config_port << 2),
 512                         DMA_CCR(imxdmac->channel));
 513
 514                imx_dmav1_writel(imxdma, d->len, DMA_CNTR(imxdmac->channel));
 515
 516                dev_dbg(imxdma->dev, "%s channel: %d dest=0x%08x src=0x%08x "
 517                        "dma_length=%d\n", __func__, imxdmac->channel,
 518                        d->dest, d->src, d->len);
 519
 520                break;
 521        /* Cyclic transfer is the same as slave_sg with special sg configuration. */
 522        case IMXDMA_DESC_CYCLIC:
 523        case IMXDMA_DESC_SLAVE_SG:
 524                if (d->direction == DMA_DEV_TO_MEM) {
 525                        imx_dmav1_writel(imxdma, imxdmac->per_address,
 526                                         DMA_SAR(imxdmac->channel));
 527                        imx_dmav1_writel(imxdma, imxdmac->ccr_from_device,
 528                                         DMA_CCR(imxdmac->channel));
 529
 530                        dev_dbg(imxdma->dev, "%s channel: %d sg=%p sgcount=%d "
 531                                "total length=%d dev_addr=0x%08x (dev2mem)\n",
 532                                __func__, imxdmac->channel, d->sg, d->sgcount,
 533                                d->len, imxdmac->per_address);
 534                } else if (d->direction == DMA_MEM_TO_DEV) {
 535                        imx_dmav1_writel(imxdma, imxdmac->per_address,
 536                                         DMA_DAR(imxdmac->channel));
 537                        imx_dmav1_writel(imxdma, imxdmac->ccr_to_device,
 538                                         DMA_CCR(imxdmac->channel));
 539
 540                        dev_dbg(imxdma->dev, "%s channel: %d sg=%p sgcount=%d "
 541                                "total length=%d dev_addr=0x%08x (mem2dev)\n",
 542                                __func__, imxdmac->channel, d->sg, d->sgcount,
 543                                d->len, imxdmac->per_address);
 544                } else {
 545                        dev_err(imxdma->dev, "%s channel: %d bad dma mode\n",
 546                                __func__, imxdmac->channel);
 547                        return -EINVAL;
 548                }
 549
 550                imxdma_sg_next(d);
 551
 552                break;
 553        default:
 554                return -EINVAL;
 555        }
 556        imxdma_enable_hw(d);
 557        return 0;
 558}
 559
 560static void imxdma_tasklet(unsigned long data)
 561{
 562        struct imxdma_channel *imxdmac = (void *)data;
 563        struct imxdma_engine *imxdma = imxdmac->imxdma;
 564        struct imxdma_desc *desc;
 565
 566        spin_lock(&imxdma->lock);
 567
 568        if (list_empty(&imxdmac->ld_active)) {
 569                /* Someone might have called terminate all */
 570                goto out;
 571        }
 572        desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc, node);
 573
 574        if (desc->desc.callback)
 575                desc->desc.callback(desc->desc.callback_param);
 576
 577        /* If we are dealing with a cyclic descriptor keep it on ld_active
 578         * and dont mark the descripor as complete.
 579         * Only in non-cyclic cases it would be marked as complete
 580         */
 581        if (imxdma_chan_is_doing_cyclic(imxdmac))
 582                goto out;
 583        else
 584                dma_cookie_complete(&desc->desc);
 585
 586        /* Free 2D slot if it was an interleaved transfer */
 587        if (imxdmac->enabled_2d) {
 588                imxdma->slots_2d[imxdmac->slot_2d].count--;
 589                imxdmac->enabled_2d = false;
 590        }
 591
 592        list_move_tail(imxdmac->ld_active.next, &imxdmac->ld_free);
 593
 594        if (!list_empty(&imxdmac->ld_queue)) {
 595                desc = list_first_entry(&imxdmac->ld_queue, struct imxdma_desc,
 596                                        node);
 597                list_move_tail(imxdmac->ld_queue.next, &imxdmac->ld_active);
 598                if (imxdma_xfer_desc(desc) < 0)
 599                        dev_warn(imxdma->dev, "%s: channel: %d couldn't xfer desc\n",
 600                                 __func__, imxdmac->channel);
 601        }
 602out:
 603        spin_unlock(&imxdma->lock);
 604}
 605
 606static int imxdma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
 607                unsigned long arg)
 608{
 609        struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
 610        struct dma_slave_config *dmaengine_cfg = (void *)arg;
 611        struct imxdma_engine *imxdma = imxdmac->imxdma;
 612        unsigned long flags;
 613        unsigned int mode = 0;
 614
 615        switch (cmd) {
 616        case DMA_TERMINATE_ALL:
 617                imxdma_disable_hw(imxdmac);
 618
 619                spin_lock_irqsave(&imxdma->lock, flags);
 620                list_splice_tail_init(&imxdmac->ld_active, &imxdmac->ld_free);
 621                list_splice_tail_init(&imxdmac->ld_queue, &imxdmac->ld_free);
 622                spin_unlock_irqrestore(&imxdma->lock, flags);
 623                return 0;
 624        case DMA_SLAVE_CONFIG:
 625                if (dmaengine_cfg->direction == DMA_DEV_TO_MEM) {
 626                        imxdmac->per_address = dmaengine_cfg->src_addr;
 627                        imxdmac->watermark_level = dmaengine_cfg->src_maxburst;
 628                        imxdmac->word_size = dmaengine_cfg->src_addr_width;
 629                } else {
 630                        imxdmac->per_address = dmaengine_cfg->dst_addr;
 631                        imxdmac->watermark_level = dmaengine_cfg->dst_maxburst;
 632                        imxdmac->word_size = dmaengine_cfg->dst_addr_width;
 633                }
 634
 635                switch (imxdmac->word_size) {
 636                case DMA_SLAVE_BUSWIDTH_1_BYTE:
 637                        mode = IMX_DMA_MEMSIZE_8;
 638                        break;
 639                case DMA_SLAVE_BUSWIDTH_2_BYTES:
 640                        mode = IMX_DMA_MEMSIZE_16;
 641                        break;
 642                default:
 643                case DMA_SLAVE_BUSWIDTH_4_BYTES:
 644                        mode = IMX_DMA_MEMSIZE_32;
 645                        break;
 646                }
 647
 648                imxdmac->hw_chaining = 1;
 649                if (!imxdma_hw_chain(imxdmac))
 650                        return -EINVAL;
 651                imxdmac->ccr_from_device = (mode | IMX_DMA_TYPE_FIFO) |
 652                        ((IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) << 2) |
 653                        CCR_REN;
 654                imxdmac->ccr_to_device =
 655                        (IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) |
 656                        ((mode | IMX_DMA_TYPE_FIFO) << 2) | CCR_REN;
 657                imx_dmav1_writel(imxdma, imxdmac->dma_request,
 658                                 DMA_RSSR(imxdmac->channel));
 659
 660                /* Set burst length */
 661                imx_dmav1_writel(imxdma, imxdmac->watermark_level *
 662                                imxdmac->word_size, DMA_BLR(imxdmac->channel));
 663
 664                return 0;
 665        default:
 666                return -ENOSYS;
 667        }
 668
 669        return -EINVAL;
 670}
 671
 672static enum dma_status imxdma_tx_status(struct dma_chan *chan,
 673                                            dma_cookie_t cookie,
 674                                            struct dma_tx_state *txstate)
 675{
 676        return dma_cookie_status(chan, cookie, txstate);
 677}
 678
 679static dma_cookie_t imxdma_tx_submit(struct dma_async_tx_descriptor *tx)
 680{
 681        struct imxdma_channel *imxdmac = to_imxdma_chan(tx->chan);
 682        struct imxdma_engine *imxdma = imxdmac->imxdma;
 683        dma_cookie_t cookie;
 684        unsigned long flags;
 685
 686        spin_lock_irqsave(&imxdma->lock, flags);
 687        list_move_tail(imxdmac->ld_free.next, &imxdmac->ld_queue);
 688        cookie = dma_cookie_assign(tx);
 689        spin_unlock_irqrestore(&imxdma->lock, flags);
 690
 691        return cookie;
 692}
 693
 694static int imxdma_alloc_chan_resources(struct dma_chan *chan)
 695{
 696        struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
 697        struct imx_dma_data *data = chan->private;
 698
 699        if (data != NULL)
 700                imxdmac->dma_request = data->dma_request;
 701
 702        while (imxdmac->descs_allocated < IMXDMA_MAX_CHAN_DESCRIPTORS) {
 703                struct imxdma_desc *desc;
 704
 705                desc = kzalloc(sizeof(*desc), GFP_KERNEL);
 706                if (!desc)
 707                        break;
 708                __memzero(&desc->desc, sizeof(struct dma_async_tx_descriptor));
 709                dma_async_tx_descriptor_init(&desc->desc, chan);
 710                desc->desc.tx_submit = imxdma_tx_submit;
 711                /* txd.flags will be overwritten in prep funcs */
 712                desc->desc.flags = DMA_CTRL_ACK;
 713                desc->status = DMA_SUCCESS;
 714
 715                list_add_tail(&desc->node, &imxdmac->ld_free);
 716                imxdmac->descs_allocated++;
 717        }
 718
 719        if (!imxdmac->descs_allocated)
 720                return -ENOMEM;
 721
 722        return imxdmac->descs_allocated;
 723}
 724
 725static void imxdma_free_chan_resources(struct dma_chan *chan)
 726{
 727        struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
 728        struct imxdma_engine *imxdma = imxdmac->imxdma;
 729        struct imxdma_desc *desc, *_desc;
 730        unsigned long flags;
 731
 732        spin_lock_irqsave(&imxdma->lock, flags);
 733
 734        imxdma_disable_hw(imxdmac);
 735        list_splice_tail_init(&imxdmac->ld_active, &imxdmac->ld_free);
 736        list_splice_tail_init(&imxdmac->ld_queue, &imxdmac->ld_free);
 737
 738        spin_unlock_irqrestore(&imxdma->lock, flags);
 739
 740        list_for_each_entry_safe(desc, _desc, &imxdmac->ld_free, node) {
 741                kfree(desc);
 742                imxdmac->descs_allocated--;
 743        }
 744        INIT_LIST_HEAD(&imxdmac->ld_free);
 745
 746        if (imxdmac->sg_list) {
 747                kfree(imxdmac->sg_list);
 748                imxdmac->sg_list = NULL;
 749        }
 750}
 751
 752static struct dma_async_tx_descriptor *imxdma_prep_slave_sg(
 753                struct dma_chan *chan, struct scatterlist *sgl,
 754                unsigned int sg_len, enum dma_transfer_direction direction,
 755                unsigned long flags, void *context)
 756{
 757        struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
 758        struct scatterlist *sg;
 759        int i, dma_length = 0;
 760        struct imxdma_desc *desc;
 761
 762        if (list_empty(&imxdmac->ld_free) ||
 763            imxdma_chan_is_doing_cyclic(imxdmac))
 764                return NULL;
 765
 766        desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
 767
 768        for_each_sg(sgl, sg, sg_len, i) {
 769                dma_length += sg_dma_len(sg);
 770        }
 771
 772        switch (imxdmac->word_size) {
 773        case DMA_SLAVE_BUSWIDTH_4_BYTES:
 774                if (sg_dma_len(sgl) & 3 || sgl->dma_address & 3)
 775                        return NULL;
 776                break;
 777        case DMA_SLAVE_BUSWIDTH_2_BYTES:
 778                if (sg_dma_len(sgl) & 1 || sgl->dma_address & 1)
 779                        return NULL;
 780                break;
 781        case DMA_SLAVE_BUSWIDTH_1_BYTE:
 782                break;
 783        default:
 784                return NULL;
 785        }
 786
 787        desc->type = IMXDMA_DESC_SLAVE_SG;
 788        desc->sg = sgl;
 789        desc->sgcount = sg_len;
 790        desc->len = dma_length;
 791        desc->direction = direction;
 792        if (direction == DMA_DEV_TO_MEM) {
 793                desc->src = imxdmac->per_address;
 794        } else {
 795                desc->dest = imxdmac->per_address;
 796        }
 797        desc->desc.callback = NULL;
 798        desc->desc.callback_param = NULL;
 799
 800        return &desc->desc;
 801}
 802
 803static struct dma_async_tx_descriptor *imxdma_prep_dma_cyclic(
 804                struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
 805                size_t period_len, enum dma_transfer_direction direction,
 806                void *context)
 807{
 808        struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
 809        struct imxdma_engine *imxdma = imxdmac->imxdma;
 810        struct imxdma_desc *desc;
 811        int i;
 812        unsigned int periods = buf_len / period_len;
 813
 814        dev_dbg(imxdma->dev, "%s channel: %d buf_len=%d period_len=%d\n",
 815                        __func__, imxdmac->channel, buf_len, period_len);
 816
 817        if (list_empty(&imxdmac->ld_free) ||
 818            imxdma_chan_is_doing_cyclic(imxdmac))
 819                return NULL;
 820
 821        desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
 822
 823        if (imxdmac->sg_list)
 824                kfree(imxdmac->sg_list);
 825
 826        imxdmac->sg_list = kcalloc(periods + 1,
 827                        sizeof(struct scatterlist), GFP_KERNEL);
 828        if (!imxdmac->sg_list)
 829                return NULL;
 830
 831        sg_init_table(imxdmac->sg_list, periods);
 832
 833        for (i = 0; i < periods; i++) {
 834                imxdmac->sg_list[i].page_link = 0;
 835                imxdmac->sg_list[i].offset = 0;
 836                imxdmac->sg_list[i].dma_address = dma_addr;
 837                sg_dma_len(&imxdmac->sg_list[i]) = period_len;
 838                dma_addr += period_len;
 839        }
 840
 841        /* close the loop */
 842        imxdmac->sg_list[periods].offset = 0;
 843        sg_dma_len(&imxdmac->sg_list[periods]) = 0;
 844        imxdmac->sg_list[periods].page_link =
 845                ((unsigned long)imxdmac->sg_list | 0x01) & ~0x02;
 846
 847        desc->type = IMXDMA_DESC_CYCLIC;
 848        desc->sg = imxdmac->sg_list;
 849        desc->sgcount = periods;
 850        desc->len = IMX_DMA_LENGTH_LOOP;
 851        desc->direction = direction;
 852        if (direction == DMA_DEV_TO_MEM) {
 853                desc->src = imxdmac->per_address;
 854        } else {
 855                desc->dest = imxdmac->per_address;
 856        }
 857        desc->desc.callback = NULL;
 858        desc->desc.callback_param = NULL;
 859
 860        return &desc->desc;
 861}
 862
 863static struct dma_async_tx_descriptor *imxdma_prep_dma_memcpy(
 864        struct dma_chan *chan, dma_addr_t dest,
 865        dma_addr_t src, size_t len, unsigned long flags)
 866{
 867        struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
 868        struct imxdma_engine *imxdma = imxdmac->imxdma;
 869        struct imxdma_desc *desc;
 870
 871        dev_dbg(imxdma->dev, "%s channel: %d src=0x%x dst=0x%x len=%d\n",
 872                        __func__, imxdmac->channel, src, dest, len);
 873
 874        if (list_empty(&imxdmac->ld_free) ||
 875            imxdma_chan_is_doing_cyclic(imxdmac))
 876                return NULL;
 877
 878        desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
 879
 880        desc->type = IMXDMA_DESC_MEMCPY;
 881        desc->src = src;
 882        desc->dest = dest;
 883        desc->len = len;
 884        desc->direction = DMA_MEM_TO_MEM;
 885        desc->config_port = IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR;
 886        desc->config_mem = IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR;
 887        desc->desc.callback = NULL;
 888        desc->desc.callback_param = NULL;
 889
 890        return &desc->desc;
 891}
 892
 893static struct dma_async_tx_descriptor *imxdma_prep_dma_interleaved(
 894        struct dma_chan *chan, struct dma_interleaved_template *xt,
 895        unsigned long flags)
 896{
 897        struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
 898        struct imxdma_engine *imxdma = imxdmac->imxdma;
 899        struct imxdma_desc *desc;
 900
 901        dev_dbg(imxdma->dev, "%s channel: %d src_start=0x%x dst_start=0x%x\n"
 902                "   src_sgl=%s dst_sgl=%s numf=%d frame_size=%d\n", __func__,
 903                imxdmac->channel, xt->src_start, xt->dst_start,
 904                xt->src_sgl ? "true" : "false", xt->dst_sgl ? "true" : "false",
 905                xt->numf, xt->frame_size);
 906
 907        if (list_empty(&imxdmac->ld_free) ||
 908            imxdma_chan_is_doing_cyclic(imxdmac))
 909                return NULL;
 910
 911        if (xt->frame_size != 1 || xt->numf <= 0 || xt->dir != DMA_MEM_TO_MEM)
 912                return NULL;
 913
 914        desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
 915
 916        desc->type = IMXDMA_DESC_INTERLEAVED;
 917        desc->src = xt->src_start;
 918        desc->dest = xt->dst_start;
 919        desc->x = xt->sgl[0].size;
 920        desc->y = xt->numf;
 921        desc->w = xt->sgl[0].icg + desc->x;
 922        desc->len = desc->x * desc->y;
 923        desc->direction = DMA_MEM_TO_MEM;
 924        desc->config_port = IMX_DMA_MEMSIZE_32;
 925        desc->config_mem = IMX_DMA_MEMSIZE_32;
 926        if (xt->src_sgl)
 927                desc->config_mem |= IMX_DMA_TYPE_2D;
 928        if (xt->dst_sgl)
 929                desc->config_port |= IMX_DMA_TYPE_2D;
 930        desc->desc.callback = NULL;
 931        desc->desc.callback_param = NULL;
 932
 933        return &desc->desc;
 934}
 935
 936static void imxdma_issue_pending(struct dma_chan *chan)
 937{
 938        struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
 939        struct imxdma_engine *imxdma = imxdmac->imxdma;
 940        struct imxdma_desc *desc;
 941        unsigned long flags;
 942
 943        spin_lock_irqsave(&imxdma->lock, flags);
 944        if (list_empty(&imxdmac->ld_active) &&
 945            !list_empty(&imxdmac->ld_queue)) {
 946                desc = list_first_entry(&imxdmac->ld_queue,
 947                                        struct imxdma_desc, node);
 948
 949                if (imxdma_xfer_desc(desc) < 0) {
 950                        dev_warn(imxdma->dev,
 951                                 "%s: channel: %d couldn't issue DMA xfer\n",
 952                                 __func__, imxdmac->channel);
 953                } else {
 954                        list_move_tail(imxdmac->ld_queue.next,
 955                                       &imxdmac->ld_active);
 956                }
 957        }
 958        spin_unlock_irqrestore(&imxdma->lock, flags);
 959}
 960
 961static int __init imxdma_probe(struct platform_device *pdev)
 962        {
 963        struct imxdma_engine *imxdma;
 964        int ret, i;
 965
 966
 967        imxdma = kzalloc(sizeof(*imxdma), GFP_KERNEL);
 968        if (!imxdma)
 969                return -ENOMEM;
 970
 971        if (cpu_is_mx1()) {
 972                imxdma->base = MX1_IO_ADDRESS(MX1_DMA_BASE_ADDR);
 973        } else if (cpu_is_mx21()) {
 974                imxdma->base = MX21_IO_ADDRESS(MX21_DMA_BASE_ADDR);
 975        } else if (cpu_is_mx27()) {
 976                imxdma->base = MX27_IO_ADDRESS(MX27_DMA_BASE_ADDR);
 977        } else {
 978                kfree(imxdma);
 979                return 0;
 980        }
 981
 982        imxdma->dma_ipg = devm_clk_get(&pdev->dev, "ipg");
 983        if (IS_ERR(imxdma->dma_ipg)) {
 984                ret = PTR_ERR(imxdma->dma_ipg);
 985                goto err_clk;
 986        }
 987
 988        imxdma->dma_ahb = devm_clk_get(&pdev->dev, "ahb");
 989        if (IS_ERR(imxdma->dma_ahb)) {
 990                ret = PTR_ERR(imxdma->dma_ahb);
 991                goto err_clk;
 992        }
 993
 994        clk_prepare_enable(imxdma->dma_ipg);
 995        clk_prepare_enable(imxdma->dma_ahb);
 996
 997        /* reset DMA module */
 998        imx_dmav1_writel(imxdma, DCR_DRST, DMA_DCR);
 999
1000        if (cpu_is_mx1()) {
1001                ret = request_irq(MX1_DMA_INT, dma_irq_handler, 0, "DMA", imxdma);
1002                if (ret) {
1003                        dev_warn(imxdma->dev, "Can't register IRQ for DMA\n");
1004                        goto err_enable;
1005                }
1006
1007                ret = request_irq(MX1_DMA_ERR, imxdma_err_handler, 0, "DMA", imxdma);
1008                if (ret) {
1009                        dev_warn(imxdma->dev, "Can't register ERRIRQ for DMA\n");
1010                        free_irq(MX1_DMA_INT, NULL);
1011                        goto err_enable;
1012                }
1013        }
1014
1015        /* enable DMA module */
1016        imx_dmav1_writel(imxdma, DCR_DEN, DMA_DCR);
1017
1018        /* clear all interrupts */
1019        imx_dmav1_writel(imxdma, (1 << IMX_DMA_CHANNELS) - 1, DMA_DISR);
1020
1021        /* disable interrupts */
1022        imx_dmav1_writel(imxdma, (1 << IMX_DMA_CHANNELS) - 1, DMA_DIMR);
1023
1024        INIT_LIST_HEAD(&imxdma->dma_device.channels);
1025
1026        dma_cap_set(DMA_SLAVE, imxdma->dma_device.cap_mask);
1027        dma_cap_set(DMA_CYCLIC, imxdma->dma_device.cap_mask);
1028        dma_cap_set(DMA_MEMCPY, imxdma->dma_device.cap_mask);
1029        dma_cap_set(DMA_INTERLEAVE, imxdma->dma_device.cap_mask);
1030
1031        /* Initialize 2D global parameters */
1032        for (i = 0; i < IMX_DMA_2D_SLOTS; i++)
1033                imxdma->slots_2d[i].count = 0;
1034
1035        spin_lock_init(&imxdma->lock);
1036
1037        /* Initialize channel parameters */
1038        for (i = 0; i < IMX_DMA_CHANNELS; i++) {
1039                struct imxdma_channel *imxdmac = &imxdma->channel[i];
1040
1041                if (cpu_is_mx21() || cpu_is_mx27()) {
1042                        ret = request_irq(MX2x_INT_DMACH0 + i,
1043                                        dma_irq_handler, 0, "DMA", imxdma);
1044                        if (ret) {
1045                                dev_warn(imxdma->dev, "Can't register IRQ %d "
1046                                         "for DMA channel %d\n",
1047                                         MX2x_INT_DMACH0 + i, i);
1048                                goto err_init;
1049                        }
1050                        init_timer(&imxdmac->watchdog);
1051                        imxdmac->watchdog.function = &imxdma_watchdog;
1052                        imxdmac->watchdog.data = (unsigned long)imxdmac;
1053                }
1054
1055                imxdmac->imxdma = imxdma;
1056
1057                INIT_LIST_HEAD(&imxdmac->ld_queue);
1058                INIT_LIST_HEAD(&imxdmac->ld_free);
1059                INIT_LIST_HEAD(&imxdmac->ld_active);
1060
1061                tasklet_init(&imxdmac->dma_tasklet, imxdma_tasklet,
1062                             (unsigned long)imxdmac);
1063                imxdmac->chan.device = &imxdma->dma_device;
1064                dma_cookie_init(&imxdmac->chan);
1065                imxdmac->channel = i;
1066
1067                /* Add the channel to the DMAC list */
1068                list_add_tail(&imxdmac->chan.device_node,
1069                              &imxdma->dma_device.channels);
1070        }
1071
1072        imxdma->dev = &pdev->dev;
1073        imxdma->dma_device.dev = &pdev->dev;
1074
1075        imxdma->dma_device.device_alloc_chan_resources = imxdma_alloc_chan_resources;
1076        imxdma->dma_device.device_free_chan_resources = imxdma_free_chan_resources;
1077        imxdma->dma_device.device_tx_status = imxdma_tx_status;
1078        imxdma->dma_device.device_prep_slave_sg = imxdma_prep_slave_sg;
1079        imxdma->dma_device.device_prep_dma_cyclic = imxdma_prep_dma_cyclic;
1080        imxdma->dma_device.device_prep_dma_memcpy = imxdma_prep_dma_memcpy;
1081        imxdma->dma_device.device_prep_interleaved_dma = imxdma_prep_dma_interleaved;
1082        imxdma->dma_device.device_control = imxdma_control;
1083        imxdma->dma_device.device_issue_pending = imxdma_issue_pending;
1084
1085        platform_set_drvdata(pdev, imxdma);
1086
1087        imxdma->dma_device.copy_align = 2; /* 2^2 = 4 bytes alignment */
1088        imxdma->dma_device.dev->dma_parms = &imxdma->dma_parms;
1089        dma_set_max_seg_size(imxdma->dma_device.dev, 0xffffff);
1090
1091        ret = dma_async_device_register(&imxdma->dma_device);
1092        if (ret) {
1093                dev_err(&pdev->dev, "unable to register\n");
1094                goto err_init;
1095        }
1096
1097        return 0;
1098
1099err_init:
1100
1101        if (cpu_is_mx21() || cpu_is_mx27()) {
1102                while (--i >= 0)
1103                        free_irq(MX2x_INT_DMACH0 + i, NULL);
1104        } else if cpu_is_mx1() {
1105                free_irq(MX1_DMA_INT, NULL);
1106                free_irq(MX1_DMA_ERR, NULL);
1107        }
1108err_enable:
1109        clk_disable_unprepare(imxdma->dma_ipg);
1110        clk_disable_unprepare(imxdma->dma_ahb);
1111err_clk:
1112        kfree(imxdma);
1113        return ret;
1114}
1115
1116static int __exit imxdma_remove(struct platform_device *pdev)
1117{
1118        struct imxdma_engine *imxdma = platform_get_drvdata(pdev);
1119        int i;
1120
1121        dma_async_device_unregister(&imxdma->dma_device);
1122
1123        if (cpu_is_mx21() || cpu_is_mx27()) {
1124                for (i = 0; i < IMX_DMA_CHANNELS; i++)
1125                        free_irq(MX2x_INT_DMACH0 + i, NULL);
1126        } else if cpu_is_mx1() {
1127                free_irq(MX1_DMA_INT, NULL);
1128                free_irq(MX1_DMA_ERR, NULL);
1129        }
1130
1131        clk_disable_unprepare(imxdma->dma_ipg);
1132        clk_disable_unprepare(imxdma->dma_ahb);
1133        kfree(imxdma);
1134
1135        return 0;
1136}
1137
1138static struct platform_driver imxdma_driver = {
1139        .driver         = {
1140                .name   = "imx-dma",
1141        },
1142        .remove         = __exit_p(imxdma_remove),
1143};
1144
1145static int __init imxdma_module_init(void)
1146{
1147        return platform_driver_probe(&imxdma_driver, imxdma_probe);
1148}
1149subsys_initcall(imxdma_module_init);
1150
1151MODULE_AUTHOR("Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>");
1152MODULE_DESCRIPTION("i.MX dma driver");
1153MODULE_LICENSE("GPL");
1154
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.