sound/soc/meson/axg-tdm-formatter.c

   1 // SPDX-License-Identifier: (GPL-2.0 OR MIT)
   2 //
   3 // Copyright (c) 2018 BayLibre, SAS.
   4 // Author: Jerome Brunet <jbrunet@baylibre.com>
   5
   6 #include <linux/clk.h>
   7 #include <linux/module.h>
   8 #include <linux/of_platform.h>
   9 #include <linux/regmap.h>
  10 #include <sound/soc.h>
  11
  12 #include "axg-tdm-formatter.h"
  13
  14 struct axg_tdm_formatter {
  15         struct list_head list;
  16         struct axg_tdm_stream *stream;
  17         const struct axg_tdm_formatter_driver *drv;
  18         struct clk *pclk;
  19         struct clk *sclk;
  20         struct clk *lrclk;
  21         struct clk *sclk_sel;
  22         struct clk *lrclk_sel;
  23         bool enabled;
  24         struct regmap *map;
  25 };
  26
  27 int axg_tdm_formatter_set_channel_masks(struct regmap *map,
  28                                         struct axg_tdm_stream *ts,
  29                                         unsigned int offset)
  30 {
  31         unsigned int val, ch = ts->channels;
  32         unsigned long mask;
  33         int i, j;
  34
  35         /*
  36          * Distribute the channels of the stream over the available slots
  37          * of each TDM lane
  38          */
  39         for (i = 0; i < AXG_TDM_NUM_LANES; i++) {
  40                 val = 0;
  41                 mask = ts->mask[i];
  42
  43                 for (j = find_first_bit(&mask, 32);
  44                      (j < 32) && ch;
  45                      j = find_next_bit(&mask, 32, j + 1)) {
  46                         val |= 1 << j;
  47                         ch -= 1;
  48                 }
  49
  50                 regmap_write(map, offset, val);
  51                 offset += regmap_get_reg_stride(map);
  52         }
  53
  54         /*
  55          * If we still have channel left at the end of the process, it means
  56          * the stream has more channels than we can accommodate and we should
  57          * have caught this earlier.
  58          */
  59         if (WARN_ON(ch != 0)) {
  60                 pr_err("channel mask error\n");
  61                 return -EINVAL;
  62         }
  63
  64         return 0;
  65 }
  66 EXPORT_SYMBOL_GPL(axg_tdm_formatter_set_channel_masks);
  67
  68 static int axg_tdm_formatter_enable(struct axg_tdm_formatter *formatter)
  69 {
  70         struct axg_tdm_stream *ts = formatter->stream;
  71         bool invert = formatter->drv->invert_sclk;
  72         int ret;
  73
  74         /* Do nothing if the formatter is already enabled */
  75         if (formatter->enabled)
  76                 return 0;
  77
  78         /*
  79          * If sclk is inverted, invert it back and provide the inversion
  80          * required by the formatter
  81          */
  82         invert ^= axg_tdm_sclk_invert(ts->iface->fmt);
  83         ret = clk_set_phase(formatter->sclk, invert ? 180 : 0);
  84         if (ret)
  85                 return ret;
  86
  87         /* Setup the stream parameter in the formatter */
  88         ret = formatter->drv->ops->prepare(formatter->map, formatter->stream);
  89         if (ret)
  90                 return ret;
  91
  92         /* Enable the signal clocks feeding the formatter */
  93         ret = clk_prepare_enable(formatter->sclk);
  94         if (ret)
  95                 return ret;
  96
  97         ret = clk_prepare_enable(formatter->lrclk);
  98         if (ret) {
  99                 clk_disable_unprepare(formatter->sclk);
 100                 return ret;
 101         }
 102
 103         /* Finally, actually enable the formatter */
 104         formatter->drv->ops->enable(formatter->map);
 105         formatter->enabled = true;
 106
 107         return 0;
 108 }
 109
 110 static void axg_tdm_formatter_disable(struct axg_tdm_formatter *formatter)
 111 {
 112         /* Do nothing if the formatter is already disabled */
 113         if (!formatter->enabled)
 114                 return;
 115
 116         formatter->drv->ops->disable(formatter->map);
 117         clk_disable_unprepare(formatter->lrclk);
 118         clk_disable_unprepare(formatter->sclk);
 119         formatter->enabled = false;
 120 }
 121
 122 static int axg_tdm_formatter_attach(struct axg_tdm_formatter *formatter)
 123 {
 124         struct axg_tdm_stream *ts = formatter->stream;
 125         int ret = 0;
 126
 127         mutex_lock(&ts->lock);
 128
 129         /* Catch up if the stream is already running when we attach */
 130         if (ts->ready) {
 131                 ret = axg_tdm_formatter_enable(formatter);
 132                 if (ret) {
 133                         pr_err("failed to enable formatter\n");
 134                         goto out;
 135                 }
 136         }
 137
 138         list_add_tail(&formatter->list, &ts->formatter_list);
 139 out:
 140         mutex_unlock(&ts->lock);
 141         return ret;
 142 }
 143
 144 static void axg_tdm_formatter_dettach(struct axg_tdm_formatter *formatter)
 145 {
 146         struct axg_tdm_stream *ts = formatter->stream;
 147
 148         mutex_lock(&ts->lock);
 149         list_del(&formatter->list);
 150         mutex_unlock(&ts->lock);
 151
 152         axg_tdm_formatter_disable(formatter);
 153 }
 154
 155 static int axg_tdm_formatter_power_up(struct axg_tdm_formatter *formatter,
 156                                       struct snd_soc_dapm_widget *w)
 157 {
 158         struct axg_tdm_stream *ts = formatter->drv->ops->get_stream(w);
 159         int ret;
 160
 161         /*
 162          * If we don't get a stream at this stage, it would mean that the
 163          * widget is powering up but is not attached to any backend DAI.
 164          * It should not happen, ever !
 165          */
 166         if (WARN_ON(!ts))
 167                 return -ENODEV;
 168
 169         /* Clock our device */
 170         ret = clk_prepare_enable(formatter->pclk);
 171         if (ret)
 172                 return ret;
 173
 174         /* Reparent the bit clock to the TDM interface */
 175         ret = clk_set_parent(formatter->sclk_sel, ts->iface->sclk);
 176         if (ret)
 177                 goto disable_pclk;
 178
 179         /* Reparent the sample clock to the TDM interface */
 180         ret = clk_set_parent(formatter->lrclk_sel, ts->iface->lrclk);
 181         if (ret)
 182                 goto disable_pclk;
 183
 184         formatter->stream = ts;
 185         ret = axg_tdm_formatter_attach(formatter);
 186         if (ret)
 187                 goto disable_pclk;
 188
 189         return 0;
 190
 191 disable_pclk:
 192         clk_disable_unprepare(formatter->pclk);
 193         return ret;
 194 }
 195
 196 static void axg_tdm_formatter_power_down(struct axg_tdm_formatter *formatter)
 197 {
 198         axg_tdm_formatter_dettach(formatter);
 199         clk_disable_unprepare(formatter->pclk);
 200         formatter->stream = NULL;
 201 }
 202
 203 int axg_tdm_formatter_event(struct snd_soc_dapm_widget *w,
 204                             struct snd_kcontrol *control,
 205                             int event)
 206 {
 207         struct snd_soc_component *c = snd_soc_dapm_to_component(w->dapm);
 208         struct axg_tdm_formatter *formatter = snd_soc_component_get_drvdata(c);
 209         int ret = 0;
 210
 211         switch (event) {
 212         case SND_SOC_DAPM_PRE_PMU:
 213                 ret = axg_tdm_formatter_power_up(formatter, w);
 214                 break;
 215
 216         case SND_SOC_DAPM_PRE_PMD:
 217                 axg_tdm_formatter_power_down(formatter);
 218                 break;
 219
 220         default:
 221                 dev_err(c->dev, "Unexpected event %d\n", event);
 222                 return -EINVAL;
 223         }
 224
 225         return ret;
 226 }
 227 EXPORT_SYMBOL_GPL(axg_tdm_formatter_event);
 228
 229 int axg_tdm_formatter_probe(struct platform_device *pdev)
 230 {
 231         struct device *dev = &pdev->dev;
 232         const struct axg_tdm_formatter_driver *drv;
 233         struct axg_tdm_formatter *formatter;
 234         struct resource *res;
 235         void __iomem *regs;
 236         int ret;
 237
 238         drv = of_device_get_match_data(dev);
 239         if (!drv) {
 240                 dev_err(dev, "failed to match device\n");
 241                 return -ENODEV;
 242         }
 243
 244         formatter = devm_kzalloc(dev, sizeof(*formatter), GFP_KERNEL);
 245         if (!formatter)
 246                 return -ENOMEM;
 247         platform_set_drvdata(pdev, formatter);
 248         formatter->drv = drv;
 249
 250         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 251         regs = devm_ioremap_resource(dev, res);
 252         if (IS_ERR(regs))
 253                 return PTR_ERR(regs);
 254
 255         formatter->map = devm_regmap_init_mmio(dev, regs, drv->regmap_cfg);
 256         if (IS_ERR(formatter->map)) {
 257                 dev_err(dev, "failed to init regmap: %ld\n",
 258                         PTR_ERR(formatter->map));
 259                 return PTR_ERR(formatter->map);
 260         }
 261
 262         /* Peripharal clock */
 263         formatter->pclk = devm_clk_get(dev, "pclk");
 264         if (IS_ERR(formatter->pclk)) {
 265                 ret = PTR_ERR(formatter->pclk);
 266                 if (ret != -EPROBE_DEFER)
 267                         dev_err(dev, "failed to get pclk: %d\n", ret);
 268                 return ret;
 269         }
 270
 271         /* Formatter bit clock */
 272         formatter->sclk = devm_clk_get(dev, "sclk");
 273         if (IS_ERR(formatter->sclk)) {
 274                 ret = PTR_ERR(formatter->sclk);
 275                 if (ret != -EPROBE_DEFER)
 276                         dev_err(dev, "failed to get sclk: %d\n", ret);
 277                 return ret;
 278         }
 279
 280         /* Formatter sample clock */
 281         formatter->lrclk = devm_clk_get(dev, "lrclk");
 282         if (IS_ERR(formatter->lrclk)) {
 283                 ret = PTR_ERR(formatter->lrclk);
 284                 if (ret != -EPROBE_DEFER)
 285                         dev_err(dev, "failed to get lrclk: %d\n", ret);
 286                 return ret;
 287         }
 288
 289         /* Formatter bit clock input multiplexer */
 290         formatter->sclk_sel = devm_clk_get(dev, "sclk_sel");
 291         if (IS_ERR(formatter->sclk_sel)) {
 292                 ret = PTR_ERR(formatter->sclk_sel);
 293                 if (ret != -EPROBE_DEFER)
 294                         dev_err(dev, "failed to get sclk_sel: %d\n", ret);
 295                 return ret;
 296         }
 297
 298         /* Formatter sample clock input multiplexer */
 299         formatter->lrclk_sel = devm_clk_get(dev, "lrclk_sel");
 300         if (IS_ERR(formatter->lrclk_sel)) {
 301                 ret = PTR_ERR(formatter->lrclk_sel);
 302                 if (ret != -EPROBE_DEFER)
 303                         dev_err(dev, "failed to get lrclk_sel: %d\n", ret);
 304                 return ret;
 305         }
 306
 307         return devm_snd_soc_register_component(dev, drv->component_drv,
 308                                                NULL, 0);
 309 }
 310 EXPORT_SYMBOL_GPL(axg_tdm_formatter_probe);
 311
 312 int axg_tdm_stream_start(struct axg_tdm_stream *ts)
 313 {
 314         struct axg_tdm_formatter *formatter;
 315         int ret = 0;
 316
 317         mutex_lock(&ts->lock);
 318         ts->ready = true;
 319
 320         /* Start all the formatters attached to the stream */
 321         list_for_each_entry(formatter, &ts->formatter_list, list) {
 322                 ret = axg_tdm_formatter_enable(formatter);
 323                 if (ret) {
 324                         pr_err("failed to start tdm stream\n");
 325                         goto out;
 326                 }
 327         }
 328
 329 out:
 330         mutex_unlock(&ts->lock);
 331         return ret;
 332 }
 333 EXPORT_SYMBOL_GPL(axg_tdm_stream_start);
 334
 335 void axg_tdm_stream_stop(struct axg_tdm_stream *ts)
 336 {
 337         struct axg_tdm_formatter *formatter;
 338
 339         mutex_lock(&ts->lock);
 340         ts->ready = false;
 341
 342         /* Stop all the formatters attached to the stream */
 343         list_for_each_entry(formatter, &ts->formatter_list, list) {
 344                 axg_tdm_formatter_disable(formatter);
 345         }
 346
 347         mutex_unlock(&ts->lock);
 348 }
 349 EXPORT_SYMBOL_GPL(axg_tdm_stream_stop);
 350
 351 struct axg_tdm_stream *axg_tdm_stream_alloc(struct axg_tdm_iface *iface)
 352 {
 353         struct axg_tdm_stream *ts;
 354
 355         ts = kzalloc(sizeof(*ts), GFP_KERNEL);
 356         if (ts) {
 357                 INIT_LIST_HEAD(&ts->formatter_list);
 358                 mutex_init(&ts->lock);
 359                 ts->iface = iface;
 360         }
 361
 362         return ts;
 363 }
 364 EXPORT_SYMBOL_GPL(axg_tdm_stream_alloc);
 365
 366 void axg_tdm_stream_free(struct axg_tdm_stream *ts)
 367 {
 368         /*
 369          * If the list is not empty, it would mean that one of the formatter
 370          * widget is still powered and attached to the interface while we
 371          * we are removing the TDM DAI. It should not be possible
 372          */
 373         WARN_ON(!list_empty(&ts->formatter_list));
 374         mutex_destroy(&ts->lock);
 375         kfree(ts);
 376 }
 377 EXPORT_SYMBOL_GPL(axg_tdm_stream_free);
 378
 379 MODULE_DESCRIPTION("Amlogic AXG TDM formatter driver");
 380 MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
 381 MODULE_LICENSE("GPL v2");