1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * tegra20_spdif.c - Tegra20 SPDIF driver 4 * 5 * Author: Stephen Warren <swarren@nvidia.com> 6 * Copyright (C) 2011-2012 - NVIDIA, Inc. 7 */ 8 9 #include <linux/clk.h> 10 #include <linux/delay.h> 11 #include <linux/device.h> 12 #include <linux/io.h> 13 #include <linux/module.h> 14 #include <linux/of_device.h> 15 #include <linux/platform_device.h> 16 #include <linux/pm_runtime.h> 17 #include <linux/regmap.h> 18 #include <linux/reset.h> 19 #include <linux/slab.h> 20 #include <sound/core.h> 21 #include <sound/pcm.h> 22 #include <sound/pcm_params.h> 23 #include <sound/soc.h> 24 #include <sound/dmaengine_pcm.h> 25 26 #include "tegra20_spdif.h" 27 28 static __maybe_unused int tegra20_spdif_runtime_suspend(struct device *dev) 29 { 30 struct tegra20_spdif *spdif = dev_get_drvdata(dev); 31 32 regcache_cache_only(spdif->regmap, true); 33 34 clk_disable_unprepare(spdif->clk_spdif_out); 35 36 return 0; 37 } 38 39 static __maybe_unused int tegra20_spdif_runtime_resume(struct device *dev) 40 { 41 struct tegra20_spdif *spdif = dev_get_drvdata(dev); 42 int ret; 43 44 ret = reset_control_assert(spdif->reset); 45 if (ret) 46 return ret; 47 48 ret = clk_prepare_enable(spdif->clk_spdif_out); 49 if (ret) { 50 dev_err(dev, "clk_enable failed: %d\n", ret); 51 return ret; 52 } 53 54 usleep_range(10, 100); 55 56 ret = reset_control_deassert(spdif->reset); 57 if (ret) 58 goto disable_clocks; 59 60 regcache_cache_only(spdif->regmap, false); 61 regcache_mark_dirty(spdif->regmap); 62 63 ret = regcache_sync(spdif->regmap); 64 if (ret) 65 goto disable_clocks; 66 67 return 0; 68 69 disable_clocks: 70 clk_disable_unprepare(spdif->clk_spdif_out); 71 72 return ret; 73 } 74 75 static int tegra20_spdif_hw_params(struct snd_pcm_substream *substream, 76 struct snd_pcm_hw_params *params, 77 struct snd_soc_dai *dai) 78 { 79 struct tegra20_spdif *spdif = dev_get_drvdata(dai->dev); 80 unsigned int mask = 0, val = 0; 81 int ret, spdifclock; 82 long rate; 83 84 mask |= TEGRA20_SPDIF_CTRL_PACK | 85 TEGRA20_SPDIF_CTRL_BIT_MODE_MASK; 86 switch (params_format(params)) { 87 case SNDRV_PCM_FORMAT_S16_LE: 88 val |= TEGRA20_SPDIF_CTRL_PACK | 89 TEGRA20_SPDIF_CTRL_BIT_MODE_16BIT; 90 break; 91 default: 92 return -EINVAL; 93 } 94 95 regmap_update_bits(spdif->regmap, TEGRA20_SPDIF_CTRL, mask, val); 96 97 /* 98 * FIFO trigger level must be bigger than DMA burst or equal to it, 99 * otherwise data is discarded on overflow. 100 */ 101 regmap_update_bits(spdif->regmap, TEGRA20_SPDIF_DATA_FIFO_CSR, 102 TEGRA20_SPDIF_DATA_FIFO_CSR_TX_ATN_LVL_MASK, 103 TEGRA20_SPDIF_DATA_FIFO_CSR_TX_ATN_LVL_TU4_WORD_FULL); 104 105 switch (params_rate(params)) { 106 case 32000: 107 spdifclock = 4096000; 108 break; 109 case 44100: 110 spdifclock = 5644800; 111 break; 112 case 48000: 113 spdifclock = 6144000; 114 break; 115 case 88200: 116 spdifclock = 11289600; 117 break; 118 case 96000: 119 spdifclock = 12288000; 120 break; 121 case 176400: 122 spdifclock = 22579200; 123 break; 124 case 192000: 125 spdifclock = 24576000; 126 break; 127 default: 128 return -EINVAL; 129 } 130 131 ret = clk_set_rate(spdif->clk_spdif_out, spdifclock); 132 if (ret) { 133 dev_err(dai->dev, "Can't set SPDIF clock rate: %d\n", ret); 134 return ret; 135 } 136 137 rate = clk_get_rate(spdif->clk_spdif_out); 138 if (rate != spdifclock) 139 dev_warn_once(dai->dev, 140 "SPDIF clock rate %d doesn't match requested rate %lu\n", 141 spdifclock, rate); 142 143 return 0; 144 } 145 146 static void tegra20_spdif_start_playback(struct tegra20_spdif *spdif) 147 { 148 regmap_update_bits(spdif->regmap, TEGRA20_SPDIF_CTRL, 149 TEGRA20_SPDIF_CTRL_TX_EN, 150 TEGRA20_SPDIF_CTRL_TX_EN); 151 } 152 153 static void tegra20_spdif_stop_playback(struct tegra20_spdif *spdif) 154 { 155 regmap_update_bits(spdif->regmap, TEGRA20_SPDIF_CTRL, 156 TEGRA20_SPDIF_CTRL_TX_EN, 0); 157 } 158 159 static int tegra20_spdif_trigger(struct snd_pcm_substream *substream, int cmd, 160 struct snd_soc_dai *dai) 161 { 162 struct tegra20_spdif *spdif = dev_get_drvdata(dai->dev); 163 164 switch (cmd) { 165 case SNDRV_PCM_TRIGGER_START: 166 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: 167 case SNDRV_PCM_TRIGGER_RESUME: 168 tegra20_spdif_start_playback(spdif); 169 break; 170 case SNDRV_PCM_TRIGGER_STOP: 171 case SNDRV_PCM_TRIGGER_PAUSE_PUSH: 172 case SNDRV_PCM_TRIGGER_SUSPEND: 173 tegra20_spdif_stop_playback(spdif); 174 break; 175 default: 176 return -EINVAL; 177 } 178 179 return 0; 180 } 181 182 static int tegra20_spdif_filter_rates(struct snd_pcm_hw_params *params, 183 struct snd_pcm_hw_rule *rule) 184 { 185 struct snd_interval *r = hw_param_interval(params, rule->var); 186 struct snd_soc_dai *dai = rule->private; 187 struct tegra20_spdif *spdif = dev_get_drvdata(dai->dev); 188 struct clk *parent = clk_get_parent(spdif->clk_spdif_out); 189 static const unsigned int rates[] = { 32000, 44100, 48000 }; 190 long i, parent_rate, valid_rates = 0; 191 192 parent_rate = clk_get_rate(parent); 193 if (parent_rate <= 0) { 194 dev_err(dai->dev, "Can't get parent clock rate: %ld\n", 195 parent_rate); 196 return parent_rate ?: -EINVAL; 197 } 198 199 for (i = 0; i < ARRAY_SIZE(rates); i++) { 200 if (parent_rate % (rates[i] * 128) == 0) 201 valid_rates |= BIT(i); 202 } 203 204 /* 205 * At least one rate must be valid, otherwise the parent clock isn't 206 * audio PLL. Nothing should be filtered in this case. 207 */ 208 if (!valid_rates) 209 valid_rates = BIT(ARRAY_SIZE(rates)) - 1; 210 211 return snd_interval_list(r, ARRAY_SIZE(rates), rates, valid_rates); 212 } 213 214 static int tegra20_spdif_startup(struct snd_pcm_substream *substream, 215 struct snd_soc_dai *dai) 216 { 217 if (!device_property_read_bool(dai->dev, "nvidia,fixed-parent-rate")) 218 return 0; 219 220 /* 221 * SPDIF and I2S share audio PLL. HDMI takes audio packets from SPDIF 222 * and audio may not work on some TVs if clock rate isn't precise. 223 * 224 * PLL rate is controlled by I2S side. Filter out audio rates that 225 * don't match PLL rate at the start of stream to allow both SPDIF 226 * and I2S work simultaneously, assuming that PLL rate won't be 227 * changed later on. 228 */ 229 return snd_pcm_hw_rule_add(substream->runtime, 0, 230 SNDRV_PCM_HW_PARAM_RATE, 231 tegra20_spdif_filter_rates, dai, 232 SNDRV_PCM_HW_PARAM_RATE, -1); 233 } 234 235 static int tegra20_spdif_probe(struct snd_soc_dai *dai) 236 { 237 struct tegra20_spdif *spdif = dev_get_drvdata(dai->dev); 238 239 dai->capture_dma_data = NULL; 240 dai->playback_dma_data = &spdif->playback_dma_data; 241 242 return 0; 243 } 244 245 static const struct snd_soc_dai_ops tegra20_spdif_dai_ops = { 246 .hw_params = tegra20_spdif_hw_params, 247 .trigger = tegra20_spdif_trigger, 248 .startup = tegra20_spdif_startup, 249 }; 250 251 static struct snd_soc_dai_driver tegra20_spdif_dai = { 252 .name = "tegra20-spdif", 253 .probe = tegra20_spdif_probe, 254 .playback = { 255 .stream_name = "Playback", 256 .channels_min = 2, 257 .channels_max = 2, 258 .rates = SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 | 259 SNDRV_PCM_RATE_48000, 260 .formats = SNDRV_PCM_FMTBIT_S16_LE, 261 }, 262 .ops = &tegra20_spdif_dai_ops, 263 }; 264 265 static const struct snd_soc_component_driver tegra20_spdif_component = { 266 .name = "tegra20-spdif", 267 }; 268 269 static bool tegra20_spdif_wr_rd_reg(struct device *dev, unsigned int reg) 270 { 271 switch (reg) { 272 case TEGRA20_SPDIF_CTRL: 273 case TEGRA20_SPDIF_STATUS: 274 case TEGRA20_SPDIF_STROBE_CTRL: 275 case TEGRA20_SPDIF_DATA_FIFO_CSR: 276 case TEGRA20_SPDIF_DATA_OUT: 277 case TEGRA20_SPDIF_DATA_IN: 278 case TEGRA20_SPDIF_CH_STA_RX_A: 279 case TEGRA20_SPDIF_CH_STA_RX_B: 280 case TEGRA20_SPDIF_CH_STA_RX_C: 281 case TEGRA20_SPDIF_CH_STA_RX_D: 282 case TEGRA20_SPDIF_CH_STA_RX_E: 283 case TEGRA20_SPDIF_CH_STA_RX_F: 284 case TEGRA20_SPDIF_CH_STA_TX_A: 285 case TEGRA20_SPDIF_CH_STA_TX_B: 286 case TEGRA20_SPDIF_CH_STA_TX_C: 287 case TEGRA20_SPDIF_CH_STA_TX_D: 288 case TEGRA20_SPDIF_CH_STA_TX_E: 289 case TEGRA20_SPDIF_CH_STA_TX_F: 290 case TEGRA20_SPDIF_USR_STA_RX_A: 291 case TEGRA20_SPDIF_USR_DAT_TX_A: 292 return true; 293 default: 294 return false; 295 } 296 } 297 298 static bool tegra20_spdif_volatile_reg(struct device *dev, unsigned int reg) 299 { 300 switch (reg) { 301 case TEGRA20_SPDIF_STATUS: 302 case TEGRA20_SPDIF_DATA_FIFO_CSR: 303 case TEGRA20_SPDIF_DATA_OUT: 304 case TEGRA20_SPDIF_DATA_IN: 305 case TEGRA20_SPDIF_CH_STA_RX_A: 306 case TEGRA20_SPDIF_CH_STA_RX_B: 307 case TEGRA20_SPDIF_CH_STA_RX_C: 308 case TEGRA20_SPDIF_CH_STA_RX_D: 309 case TEGRA20_SPDIF_CH_STA_RX_E: 310 case TEGRA20_SPDIF_CH_STA_RX_F: 311 case TEGRA20_SPDIF_USR_STA_RX_A: 312 case TEGRA20_SPDIF_USR_DAT_TX_A: 313 return true; 314 default: 315 return false; 316 } 317 } 318 319 static bool tegra20_spdif_precious_reg(struct device *dev, unsigned int reg) 320 { 321 switch (reg) { 322 case TEGRA20_SPDIF_DATA_OUT: 323 case TEGRA20_SPDIF_DATA_IN: 324 case TEGRA20_SPDIF_USR_STA_RX_A: 325 case TEGRA20_SPDIF_USR_DAT_TX_A: 326 return true; 327 default: 328 return false; 329 } 330 } 331 332 static const struct regmap_config tegra20_spdif_regmap_config = { 333 .reg_bits = 32, 334 .reg_stride = 4, 335 .val_bits = 32, 336 .max_register = TEGRA20_SPDIF_USR_DAT_TX_A, 337 .writeable_reg = tegra20_spdif_wr_rd_reg, 338 .readable_reg = tegra20_spdif_wr_rd_reg, 339 .volatile_reg = tegra20_spdif_volatile_reg, 340 .precious_reg = tegra20_spdif_precious_reg, 341 .cache_type = REGCACHE_FLAT, 342 }; 343 344 static int tegra20_spdif_platform_probe(struct platform_device *pdev) 345 { 346 struct tegra20_spdif *spdif; 347 struct resource *mem; 348 void __iomem *regs; 349 int ret; 350 351 spdif = devm_kzalloc(&pdev->dev, sizeof(struct tegra20_spdif), 352 GFP_KERNEL); 353 if (!spdif) 354 return -ENOMEM; 355 356 dev_set_drvdata(&pdev->dev, spdif); 357 358 spdif->reset = devm_reset_control_get_exclusive(&pdev->dev, NULL); 359 if (IS_ERR(spdif->reset)) { 360 dev_err(&pdev->dev, "Can't retrieve spdif reset\n"); 361 return PTR_ERR(spdif->reset); 362 } 363 364 spdif->clk_spdif_out = devm_clk_get(&pdev->dev, "out"); 365 if (IS_ERR(spdif->clk_spdif_out)) { 366 dev_err(&pdev->dev, "Could not retrieve spdif clock\n"); 367 return PTR_ERR(spdif->clk_spdif_out); 368 } 369 370 regs = devm_platform_get_and_ioremap_resource(pdev, 0, &mem); 371 if (IS_ERR(regs)) 372 return PTR_ERR(regs); 373 374 spdif->regmap = devm_regmap_init_mmio(&pdev->dev, regs, 375 &tegra20_spdif_regmap_config); 376 if (IS_ERR(spdif->regmap)) { 377 dev_err(&pdev->dev, "regmap init failed\n"); 378 return PTR_ERR(spdif->regmap); 379 } 380 381 spdif->playback_dma_data.addr = mem->start + TEGRA20_SPDIF_DATA_OUT; 382 spdif->playback_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 383 spdif->playback_dma_data.maxburst = 4; 384 385 ret = devm_pm_runtime_enable(&pdev->dev); 386 if (ret) 387 return ret; 388 389 ret = devm_snd_soc_register_component(&pdev->dev, 390 &tegra20_spdif_component, 391 &tegra20_spdif_dai, 1); 392 if (ret) { 393 dev_err(&pdev->dev, "Could not register DAI: %d\n", ret); 394 return ret; 395 } 396 397 ret = devm_tegra_pcm_platform_register(&pdev->dev); 398 if (ret) { 399 dev_err(&pdev->dev, "Could not register PCM: %d\n", ret); 400 return ret; 401 } 402 403 return 0; 404 } 405 406 static const struct dev_pm_ops tegra20_spdif_pm_ops = { 407 SET_RUNTIME_PM_OPS(tegra20_spdif_runtime_suspend, 408 tegra20_spdif_runtime_resume, NULL) 409 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, 410 pm_runtime_force_resume) 411 }; 412 413 static const struct of_device_id tegra20_spdif_of_match[] = { 414 { .compatible = "nvidia,tegra20-spdif", }, 415 {}, 416 }; 417 MODULE_DEVICE_TABLE(of, tegra20_spdif_of_match); 418 419 static struct platform_driver tegra20_spdif_driver = { 420 .driver = { 421 .name = "tegra20-spdif", 422 .pm = &tegra20_spdif_pm_ops, 423 .of_match_table = tegra20_spdif_of_match, 424 }, 425 .probe = tegra20_spdif_platform_probe, 426 }; 427 module_platform_driver(tegra20_spdif_driver); 428 429 MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>"); 430 MODULE_DESCRIPTION("Tegra20 SPDIF ASoC driver"); 431 MODULE_LICENSE("GPL"); 432