drivers/dma/sh/rcar-audmapp.c

   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/platform_data/dma-rcar-audmapp.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/shdma-base.h>
  28
  29 /*
  30  * DMA register
  31  */
  32 #define PDMASAR         0x00
  33 #define PDMADAR         0x04
  34 #define PDMACHCR        0x0c
  35
  36 /* PDMACHCR */
  37 #define PDMACHCR_DE             (1 << 0)
  38
  39 #define AUDMAPP_MAX_CHANNELS    29
  40
  41 /* Default MEMCPY transfer size = 2^2 = 4 bytes */
  42 #define LOG2_DEFAULT_XFER_SIZE  2
  43 #define AUDMAPP_SLAVE_NUMBER    256
  44 #define AUDMAPP_LEN_MAX         (16 * 1024 * 1024)
  45
  46 struct audmapp_chan {
  47         struct shdma_chan shdma_chan;
  48         struct audmapp_slave_config *config;
  49         void __iomem *base;
  50 };
  51
  52 struct audmapp_device {
  53         struct shdma_dev shdma_dev;
  54         struct audmapp_pdata *pdata;
  55         struct device *dev;
  56         void __iomem *chan_reg;
  57 };
  58
  59 #define to_chan(chan) container_of(chan, struct audmapp_chan, shdma_chan)
  60 #define to_dev(chan) container_of(chan->shdma_chan.dma_chan.device,     \
  61                                   struct audmapp_device, shdma_dev.dma_dev)
  62
  63 static void audmapp_write(struct audmapp_chan *auchan, u32 data, u32 reg)
  64 {
  65         struct audmapp_device *audev = to_dev(auchan);
  66         struct device *dev = audev->dev;
  67
  68         dev_dbg(dev, "w %p : %08x\n", auchan->base + reg, data);
  69
  70         iowrite32(data, auchan->base + reg);
  71 }
  72
  73 static u32 audmapp_read(struct audmapp_chan *auchan, u32 reg)
  74 {
  75         return ioread32(auchan->base + reg);
  76 }
  77
  78 static void audmapp_halt(struct shdma_chan *schan)
  79 {
  80         struct audmapp_chan *auchan = to_chan(schan);
  81         int i;
  82
  83         audmapp_write(auchan, 0, PDMACHCR);
  84
  85         for (i = 0; i < 1024; i++) {
  86                 if (0 == audmapp_read(auchan, PDMACHCR))
  87                         return;
  88                 udelay(1);
  89         }
  90 }
  91
  92 static void audmapp_start_xfer(struct shdma_chan *schan,
  93                                struct shdma_desc *sdecs)
  94 {
  95         struct audmapp_chan *auchan = to_chan(schan);
  96         struct audmapp_device *audev = to_dev(auchan);
  97         struct audmapp_slave_config *cfg = auchan->config;
  98         struct device *dev = audev->dev;
  99         u32 chcr = cfg->chcr | PDMACHCR_DE;
 100
 101         dev_dbg(dev, "src/dst/chcr = %pad/%pad/%x\n",
 102                 &cfg->src, &cfg->dst, cfg->chcr);
 103
 104         audmapp_write(auchan, cfg->src, PDMASAR);
 105         audmapp_write(auchan, cfg->dst, PDMADAR);
 106         audmapp_write(auchan, chcr,     PDMACHCR);
 107 }
 108
 109 static struct audmapp_slave_config *
 110 audmapp_find_slave(struct audmapp_chan *auchan, int slave_id)
 111 {
 112         struct audmapp_device *audev = to_dev(auchan);
 113         struct audmapp_pdata *pdata = audev->pdata;
 114         struct audmapp_slave_config *cfg;
 115         int i;
 116
 117         if (slave_id >= AUDMAPP_SLAVE_NUMBER)
 118                 return NULL;
 119
 120         for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
 121                 if (cfg->slave_id == slave_id)
 122                         return cfg;
 123
 124         return NULL;
 125 }
 126
 127 static int audmapp_set_slave(struct shdma_chan *schan, int slave_id,
 128                              dma_addr_t slave_addr, bool try)
 129 {
 130         struct audmapp_chan *auchan = to_chan(schan);
 131         struct audmapp_slave_config *cfg =
 132                 audmapp_find_slave(auchan, slave_id);
 133
 134         if (!cfg)
 135                 return -ENODEV;
 136         if (try)
 137                 return 0;
 138
 139         auchan->config  = cfg;
 140
 141         return 0;
 142 }
 143
 144 static int audmapp_desc_setup(struct shdma_chan *schan,
 145                               struct shdma_desc *sdecs,
 146                               dma_addr_t src, dma_addr_t dst, size_t *len)
 147 {
 148         struct audmapp_chan *auchan = to_chan(schan);
 149         struct audmapp_slave_config *cfg = auchan->config;
 150
 151         if (!cfg)
 152                 return -ENODEV;
 153
 154         if (*len > (size_t)AUDMAPP_LEN_MAX)
 155                 *len = (size_t)AUDMAPP_LEN_MAX;
 156
 157         return 0;
 158 }
 159
 160 static void audmapp_setup_xfer(struct shdma_chan *schan,
 161                                int slave_id)
 162 {
 163 }
 164
 165 static dma_addr_t audmapp_slave_addr(struct shdma_chan *schan)
 166 {
 167         return 0; /* always fixed address */
 168 }
 169
 170 static bool audmapp_channel_busy(struct shdma_chan *schan)
 171 {
 172         struct audmapp_chan *auchan = to_chan(schan);
 173         u32 chcr = audmapp_read(auchan, PDMACHCR);
 174
 175         return chcr & ~PDMACHCR_DE;
 176 }
 177
 178 static bool audmapp_desc_completed(struct shdma_chan *schan,
 179                                    struct shdma_desc *sdesc)
 180 {
 181         return true;
 182 }
 183
 184 static struct shdma_desc *audmapp_embedded_desc(void *buf, int i)
 185 {
 186         return &((struct shdma_desc *)buf)[i];
 187 }
 188
 189 static const struct shdma_ops audmapp_shdma_ops = {
 190         .halt_channel   = audmapp_halt,
 191         .desc_setup     = audmapp_desc_setup,
 192         .set_slave      = audmapp_set_slave,
 193         .start_xfer     = audmapp_start_xfer,
 194         .embedded_desc  = audmapp_embedded_desc,
 195         .setup_xfer     = audmapp_setup_xfer,
 196         .slave_addr     = audmapp_slave_addr,
 197         .channel_busy   = audmapp_channel_busy,
 198         .desc_completed = audmapp_desc_completed,
 199 };
 200
 201 static int audmapp_chan_probe(struct platform_device *pdev,
 202                               struct audmapp_device *audev, int id)
 203 {
 204         struct shdma_dev *sdev = &audev->shdma_dev;
 205         struct audmapp_chan *auchan;
 206         struct shdma_chan *schan;
 207         struct device *dev = audev->dev;
 208
 209         auchan = devm_kzalloc(dev, sizeof(*auchan), GFP_KERNEL);
 210         if (!auchan)
 211                 return -ENOMEM;
 212
 213         schan = &auchan->shdma_chan;
 214         schan->max_xfer_len = AUDMAPP_LEN_MAX;
 215
 216         shdma_chan_probe(sdev, schan, id);
 217
 218         auchan->base = audev->chan_reg + 0x20 + (0x10 * id);
 219         dev_dbg(dev, "%02d : %p / %p", id, auchan->base, audev->chan_reg);
 220
 221         return 0;
 222 }
 223
 224 static void audmapp_chan_remove(struct audmapp_device *audev)
 225 {
 226         struct dma_device *dma_dev = &audev->shdma_dev.dma_dev;
 227         struct shdma_chan *schan;
 228         int i;
 229
 230         shdma_for_each_chan(schan, &audev->shdma_dev, i) {
 231                 BUG_ON(!schan);
 232                 shdma_chan_remove(schan);
 233         }
 234         dma_dev->chancnt = 0;
 235 }
 236
 237 static int audmapp_probe(struct platform_device *pdev)
 238 {
 239         struct audmapp_pdata *pdata = pdev->dev.platform_data;
 240         struct audmapp_device *audev;
 241         struct shdma_dev *sdev;
 242         struct dma_device *dma_dev;
 243         struct resource *res;
 244         int err, i;
 245
 246         if (!pdata)
 247                 return -ENODEV;
 248
 249         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 250
 251         audev = devm_kzalloc(&pdev->dev, sizeof(*audev), GFP_KERNEL);
 252         if (!audev)
 253                 return -ENOMEM;
 254
 255         audev->dev      = &pdev->dev;
 256         audev->pdata    = pdata;
 257         audev->chan_reg = devm_ioremap_resource(&pdev->dev, res);
 258         if (IS_ERR(audev->chan_reg))
 259                 return PTR_ERR(audev->chan_reg);
 260
 261         sdev            = &audev->shdma_dev;
 262         sdev->ops       = &audmapp_shdma_ops;
 263         sdev->desc_size = sizeof(struct shdma_desc);
 264
 265         dma_dev                 = &sdev->dma_dev;
 266         dma_dev->copy_align     = LOG2_DEFAULT_XFER_SIZE;
 267         dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
 268
 269         err = shdma_init(&pdev->dev, sdev, AUDMAPP_MAX_CHANNELS);
 270         if (err < 0)
 271                 return err;
 272
 273         platform_set_drvdata(pdev, audev);
 274
 275         /* Create DMA Channel */
 276         for (i = 0; i < AUDMAPP_MAX_CHANNELS; i++) {
 277                 err = audmapp_chan_probe(pdev, audev, i);
 278                 if (err)
 279                         goto chan_probe_err;
 280         }
 281
 282         err = dma_async_device_register(dma_dev);
 283         if (err < 0)
 284                 goto chan_probe_err;
 285
 286         return err;
 287
 288 chan_probe_err:
 289         audmapp_chan_remove(audev);
 290         shdma_cleanup(sdev);
 291
 292         return err;
 293 }
 294
 295 static int audmapp_remove(struct platform_device *pdev)
 296 {
 297         struct audmapp_device *audev = platform_get_drvdata(pdev);
 298         struct dma_device *dma_dev = &audev->shdma_dev.dma_dev;
 299
 300         dma_async_device_unregister(dma_dev);
 301
 302         audmapp_chan_remove(audev);
 303         shdma_cleanup(&audev->shdma_dev);
 304
 305         return 0;
 306 }
 307
 308 static struct platform_driver audmapp_driver = {
 309         .probe          = audmapp_probe,
 310         .remove         = audmapp_remove,
 311         .driver         = {
 312                 .owner  = THIS_MODULE,
 313                 .name   = "rcar-audmapp-engine",
 314         },
 315 };
 316 module_platform_driver(audmapp_driver);
 317
 318 MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
 319 MODULE_DESCRIPTION("Renesas R-Car Audio DMAC peri-peri driver");
 320 MODULE_LICENSE("GPL");