linux/drivers/dma/sh/rcar-audmapp.c
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   1/*
   2 * This is for Renesas R-Car Audio-DMAC-peri-peri.
   3 *
   4 * Copyright (C) 2014 Renesas Electronics Corporation
   5 * Copyright (C) 2014 Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
   6 *
   7 * based on the drivers/dma/sh/shdma.c
   8 *
   9 * Copyright (C) 2011-2012 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
  10 * Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
  11 * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
  12 * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
  13 *
  14 * This is free software; you can redistribute it and/or modify
  15 * it under the terms of the GNU General Public License as published by
  16 * the Free Software Foundation; either version 2 of the License, or
  17 * (at your option) any later version.
  18 *
  19 */
  20#include <linux/delay.h>
  21#include <linux/init.h>
  22#include <linux/module.h>
  23#include <linux/slab.h>
  24#include <linux/dmaengine.h>
  25#include <linux/of_dma.h>
  26#include <linux/platform_data/dma-rcar-audmapp.h>
  27#include <linux/platform_device.h>
  28#include <linux/shdma-base.h>
  29
  30/*
  31 * DMA register
  32 */
  33#define PDMASAR         0x00
  34#define PDMADAR         0x04
  35#define PDMACHCR        0x0c
  36
  37/* PDMACHCR */
  38#define PDMACHCR_DE             (1 << 0)
  39
  40#define AUDMAPP_MAX_CHANNELS    29
  41
  42/* Default MEMCPY transfer size = 2^2 = 4 bytes */
  43#define LOG2_DEFAULT_XFER_SIZE  2
  44#define AUDMAPP_SLAVE_NUMBER    256
  45#define AUDMAPP_LEN_MAX         (16 * 1024 * 1024)
  46
  47struct audmapp_chan {
  48        struct shdma_chan shdma_chan;
  49        void __iomem *base;
  50        dma_addr_t slave_addr;
  51        u32 chcr;
  52};
  53
  54struct audmapp_device {
  55        struct shdma_dev shdma_dev;
  56        struct audmapp_pdata *pdata;
  57        struct device *dev;
  58        void __iomem *chan_reg;
  59};
  60
  61struct audmapp_desc {
  62        struct shdma_desc shdma_desc;
  63        dma_addr_t src;
  64        dma_addr_t dst;
  65};
  66
  67#define to_shdma_chan(c) container_of(c, struct shdma_chan, dma_chan)
  68
  69#define to_chan(chan) container_of(chan, struct audmapp_chan, shdma_chan)
  70#define to_desc(sdesc) container_of(sdesc, struct audmapp_desc, shdma_desc)
  71#define to_dev(chan) container_of(chan->shdma_chan.dma_chan.device,     \
  72                                  struct audmapp_device, shdma_dev.dma_dev)
  73
  74static void audmapp_write(struct audmapp_chan *auchan, u32 data, u32 reg)
  75{
  76        struct audmapp_device *audev = to_dev(auchan);
  77        struct device *dev = audev->dev;
  78
  79        dev_dbg(dev, "w %p : %08x\n", auchan->base + reg, data);
  80
  81        iowrite32(data, auchan->base + reg);
  82}
  83
  84static u32 audmapp_read(struct audmapp_chan *auchan, u32 reg)
  85{
  86        return ioread32(auchan->base + reg);
  87}
  88
  89static void audmapp_halt(struct shdma_chan *schan)
  90{
  91        struct audmapp_chan *auchan = to_chan(schan);
  92        int i;
  93
  94        audmapp_write(auchan, 0, PDMACHCR);
  95
  96        for (i = 0; i < 1024; i++) {
  97                if (0 == audmapp_read(auchan, PDMACHCR))
  98                        return;
  99                udelay(1);
 100        }
 101}
 102
 103static void audmapp_start_xfer(struct shdma_chan *schan,
 104                               struct shdma_desc *sdesc)
 105{
 106        struct audmapp_chan *auchan = to_chan(schan);
 107        struct audmapp_device *audev = to_dev(auchan);
 108        struct audmapp_desc *desc = to_desc(sdesc);
 109        struct device *dev = audev->dev;
 110        u32 chcr = auchan->chcr | PDMACHCR_DE;
 111
 112        dev_dbg(dev, "src/dst/chcr = %pad/%pad/%08x\n",
 113                &desc->src, &desc->dst, chcr);
 114
 115        audmapp_write(auchan, desc->src,        PDMASAR);
 116        audmapp_write(auchan, desc->dst,        PDMADAR);
 117        audmapp_write(auchan, chcr,     PDMACHCR);
 118}
 119
 120static int audmapp_get_config(struct audmapp_chan *auchan, int slave_id,
 121                              u32 *chcr, dma_addr_t *dst)
 122{
 123        struct audmapp_device *audev = to_dev(auchan);
 124        struct audmapp_pdata *pdata = audev->pdata;
 125        struct audmapp_slave_config *cfg;
 126        int i;
 127
 128        *chcr   = 0;
 129        *dst    = 0;
 130
 131        if (!pdata) { /* DT */
 132                *chcr = ((u32)slave_id) << 16;
 133                auchan->shdma_chan.slave_id = (slave_id) >> 8;
 134                return 0;
 135        }
 136
 137        /* non-DT */
 138
 139        if (slave_id >= AUDMAPP_SLAVE_NUMBER)
 140                return -ENXIO;
 141
 142        for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
 143                if (cfg->slave_id == slave_id) {
 144                        *chcr   = cfg->chcr;
 145                        *dst    = cfg->dst;
 146                        return 0;
 147                }
 148
 149        return -ENXIO;
 150}
 151
 152static int audmapp_set_slave(struct shdma_chan *schan, int slave_id,
 153                             dma_addr_t slave_addr, bool try)
 154{
 155        struct audmapp_chan *auchan = to_chan(schan);
 156        u32 chcr;
 157        dma_addr_t dst;
 158        int ret;
 159
 160        ret = audmapp_get_config(auchan, slave_id, &chcr, &dst);
 161        if (ret < 0)
 162                return ret;
 163
 164        if (try)
 165                return 0;
 166
 167        auchan->chcr            = chcr;
 168        auchan->slave_addr      = slave_addr ? : dst;
 169
 170        return 0;
 171}
 172
 173static int audmapp_desc_setup(struct shdma_chan *schan,
 174                              struct shdma_desc *sdesc,
 175                              dma_addr_t src, dma_addr_t dst, size_t *len)
 176{
 177        struct audmapp_desc *desc = to_desc(sdesc);
 178
 179        if (*len > (size_t)AUDMAPP_LEN_MAX)
 180                *len = (size_t)AUDMAPP_LEN_MAX;
 181
 182        desc->src = src;
 183        desc->dst = dst;
 184
 185        return 0;
 186}
 187
 188static void audmapp_setup_xfer(struct shdma_chan *schan,
 189                               int slave_id)
 190{
 191}
 192
 193static dma_addr_t audmapp_slave_addr(struct shdma_chan *schan)
 194{
 195        struct audmapp_chan *auchan = to_chan(schan);
 196
 197        return auchan->slave_addr;
 198}
 199
 200static bool audmapp_channel_busy(struct shdma_chan *schan)
 201{
 202        struct audmapp_chan *auchan = to_chan(schan);
 203        u32 chcr = audmapp_read(auchan, PDMACHCR);
 204
 205        return chcr & ~PDMACHCR_DE;
 206}
 207
 208static bool audmapp_desc_completed(struct shdma_chan *schan,
 209                                   struct shdma_desc *sdesc)
 210{
 211        return true;
 212}
 213
 214static struct shdma_desc *audmapp_embedded_desc(void *buf, int i)
 215{
 216        return &((struct audmapp_desc *)buf)[i].shdma_desc;
 217}
 218
 219static const struct shdma_ops audmapp_shdma_ops = {
 220        .halt_channel   = audmapp_halt,
 221        .desc_setup     = audmapp_desc_setup,
 222        .set_slave      = audmapp_set_slave,
 223        .start_xfer     = audmapp_start_xfer,
 224        .embedded_desc  = audmapp_embedded_desc,
 225        .setup_xfer     = audmapp_setup_xfer,
 226        .slave_addr     = audmapp_slave_addr,
 227        .channel_busy   = audmapp_channel_busy,
 228        .desc_completed = audmapp_desc_completed,
 229};
 230
 231static int audmapp_chan_probe(struct platform_device *pdev,
 232                              struct audmapp_device *audev, int id)
 233{
 234        struct shdma_dev *sdev = &audev->shdma_dev;
 235        struct audmapp_chan *auchan;
 236        struct shdma_chan *schan;
 237        struct device *dev = audev->dev;
 238
 239        auchan = devm_kzalloc(dev, sizeof(*auchan), GFP_KERNEL);
 240        if (!auchan)
 241                return -ENOMEM;
 242
 243        schan = &auchan->shdma_chan;
 244        schan->max_xfer_len = AUDMAPP_LEN_MAX;
 245
 246        shdma_chan_probe(sdev, schan, id);
 247
 248        auchan->base = audev->chan_reg + 0x20 + (0x10 * id);
 249        dev_dbg(dev, "%02d : %p / %p", id, auchan->base, audev->chan_reg);
 250
 251        return 0;
 252}
 253
 254static void audmapp_chan_remove(struct audmapp_device *audev)
 255{
 256        struct shdma_chan *schan;
 257        int i;
 258
 259        shdma_for_each_chan(schan, &audev->shdma_dev, i) {
 260                BUG_ON(!schan);
 261                shdma_chan_remove(schan);
 262        }
 263}
 264
 265static struct dma_chan *audmapp_of_xlate(struct of_phandle_args *dma_spec,
 266                                         struct of_dma *ofdma)
 267{
 268        dma_cap_mask_t mask;
 269        struct dma_chan *chan;
 270        u32 chcr = dma_spec->args[0];
 271
 272        if (dma_spec->args_count != 1)
 273                return NULL;
 274
 275        dma_cap_zero(mask);
 276        dma_cap_set(DMA_SLAVE, mask);
 277
 278        chan = dma_request_channel(mask, shdma_chan_filter, NULL);
 279        if (chan)
 280                to_shdma_chan(chan)->hw_req = chcr;
 281
 282        return chan;
 283}
 284
 285static int audmapp_probe(struct platform_device *pdev)
 286{
 287        struct audmapp_pdata *pdata = pdev->dev.platform_data;
 288        struct device_node *np = pdev->dev.of_node;
 289        struct audmapp_device *audev;
 290        struct shdma_dev *sdev;
 291        struct dma_device *dma_dev;
 292        struct resource *res;
 293        int err, i;
 294
 295        if (np)
 296                of_dma_controller_register(np, audmapp_of_xlate, pdev);
 297        else if (!pdata)
 298                return -ENODEV;
 299
 300        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 301
 302        audev = devm_kzalloc(&pdev->dev, sizeof(*audev), GFP_KERNEL);
 303        if (!audev)
 304                return -ENOMEM;
 305
 306        audev->dev      = &pdev->dev;
 307        audev->pdata    = pdata;
 308        audev->chan_reg = devm_ioremap_resource(&pdev->dev, res);
 309        if (IS_ERR(audev->chan_reg))
 310                return PTR_ERR(audev->chan_reg);
 311
 312        sdev            = &audev->shdma_dev;
 313        sdev->ops       = &audmapp_shdma_ops;
 314        sdev->desc_size = sizeof(struct audmapp_desc);
 315
 316        dma_dev                 = &sdev->dma_dev;
 317        dma_dev->copy_align     = LOG2_DEFAULT_XFER_SIZE;
 318        dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
 319
 320        err = shdma_init(&pdev->dev, sdev, AUDMAPP_MAX_CHANNELS);
 321        if (err < 0)
 322                return err;
 323
 324        platform_set_drvdata(pdev, audev);
 325
 326        /* Create DMA Channel */
 327        for (i = 0; i < AUDMAPP_MAX_CHANNELS; i++) {
 328                err = audmapp_chan_probe(pdev, audev, i);
 329                if (err)
 330                        goto chan_probe_err;
 331        }
 332
 333        err = dma_async_device_register(dma_dev);
 334        if (err < 0)
 335                goto chan_probe_err;
 336
 337        return err;
 338
 339chan_probe_err:
 340        audmapp_chan_remove(audev);
 341        shdma_cleanup(sdev);
 342
 343        return err;
 344}
 345
 346static int audmapp_remove(struct platform_device *pdev)
 347{
 348        struct audmapp_device *audev = platform_get_drvdata(pdev);
 349        struct dma_device *dma_dev = &audev->shdma_dev.dma_dev;
 350
 351        dma_async_device_unregister(dma_dev);
 352
 353        audmapp_chan_remove(audev);
 354        shdma_cleanup(&audev->shdma_dev);
 355
 356        return 0;
 357}
 358
 359static const struct of_device_id audmapp_of_match[] = {
 360        { .compatible = "renesas,rcar-audmapp", },
 361        {},
 362};
 363
 364static struct platform_driver audmapp_driver = {
 365        .probe          = audmapp_probe,
 366        .remove         = audmapp_remove,
 367        .driver         = {
 368                .name   = "rcar-audmapp-engine",
 369                .of_match_table = audmapp_of_match,
 370        },
 371};
 372module_platform_driver(audmapp_driver);
 373
 374MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
 375MODULE_DESCRIPTION("Renesas R-Car Audio DMAC peri-peri driver");
 376MODULE_LICENSE("GPL");
 377
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