1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2012-2013, Analog Devices Inc. 4 * Author: Lars-Peter Clausen <lars@metafoo.de> 5 */ 6 7 #include <linux/clk.h> 8 #include <linux/init.h> 9 #include <linux/kernel.h> 10 #include <linux/module.h> 11 #include <linux/of.h> 12 #include <linux/platform_device.h> 13 #include <linux/regmap.h> 14 #include <linux/slab.h> 15 16 #include <sound/core.h> 17 #include <sound/pcm.h> 18 #include <sound/pcm_params.h> 19 #include <sound/soc.h> 20 #include <sound/dmaengine_pcm.h> 21 22 #define AXI_I2S_REG_RESET 0x00 23 #define AXI_I2S_REG_CTRL 0x04 24 #define AXI_I2S_REG_CLK_CTRL 0x08 25 #define AXI_I2S_REG_STATUS 0x10 26 27 #define AXI_I2S_REG_RX_FIFO 0x28 28 #define AXI_I2S_REG_TX_FIFO 0x2C 29 30 #define AXI_I2S_RESET_GLOBAL BIT(0) 31 #define AXI_I2S_RESET_TX_FIFO BIT(1) 32 #define AXI_I2S_RESET_RX_FIFO BIT(2) 33 34 #define AXI_I2S_CTRL_TX_EN BIT(0) 35 #define AXI_I2S_CTRL_RX_EN BIT(1) 36 37 /* The frame size is configurable, but for now we always set it 64 bit */ 38 #define AXI_I2S_BITS_PER_FRAME 64 39 40 struct axi_i2s { 41 struct regmap *regmap; 42 struct clk *clk; 43 struct clk *clk_ref; 44 45 bool has_capture; 46 bool has_playback; 47 48 struct snd_soc_dai_driver dai_driver; 49 50 struct snd_dmaengine_dai_dma_data capture_dma_data; 51 struct snd_dmaengine_dai_dma_data playback_dma_data; 52 53 struct snd_ratnum ratnum; 54 struct snd_pcm_hw_constraint_ratnums rate_constraints; 55 }; 56 57 static int axi_i2s_trigger(struct snd_pcm_substream *substream, int cmd, 58 struct snd_soc_dai *dai) 59 { 60 struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai); 61 unsigned int mask, val; 62 63 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) 64 mask = AXI_I2S_CTRL_RX_EN; 65 else 66 mask = AXI_I2S_CTRL_TX_EN; 67 68 switch (cmd) { 69 case SNDRV_PCM_TRIGGER_START: 70 case SNDRV_PCM_TRIGGER_RESUME: 71 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: 72 val = mask; 73 break; 74 case SNDRV_PCM_TRIGGER_STOP: 75 case SNDRV_PCM_TRIGGER_SUSPEND: 76 case SNDRV_PCM_TRIGGER_PAUSE_PUSH: 77 val = 0; 78 break; 79 default: 80 return -EINVAL; 81 } 82 83 regmap_update_bits(i2s->regmap, AXI_I2S_REG_CTRL, mask, val); 84 85 return 0; 86 } 87 88 static int axi_i2s_hw_params(struct snd_pcm_substream *substream, 89 struct snd_pcm_hw_params *params, struct snd_soc_dai *dai) 90 { 91 struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai); 92 unsigned int bclk_div, word_size; 93 unsigned int bclk_rate; 94 95 bclk_rate = params_rate(params) * AXI_I2S_BITS_PER_FRAME; 96 97 word_size = AXI_I2S_BITS_PER_FRAME / 2 - 1; 98 bclk_div = DIV_ROUND_UP(clk_get_rate(i2s->clk_ref), bclk_rate) / 2 - 1; 99 100 regmap_write(i2s->regmap, AXI_I2S_REG_CLK_CTRL, (word_size << 16) | 101 bclk_div); 102 103 return 0; 104 } 105 106 static int axi_i2s_startup(struct snd_pcm_substream *substream, 107 struct snd_soc_dai *dai) 108 { 109 struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai); 110 uint32_t mask; 111 int ret; 112 113 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) 114 mask = AXI_I2S_RESET_RX_FIFO; 115 else 116 mask = AXI_I2S_RESET_TX_FIFO; 117 118 regmap_write(i2s->regmap, AXI_I2S_REG_RESET, mask); 119 120 ret = snd_pcm_hw_constraint_ratnums(substream->runtime, 0, 121 SNDRV_PCM_HW_PARAM_RATE, 122 &i2s->rate_constraints); 123 if (ret) 124 return ret; 125 126 return clk_prepare_enable(i2s->clk_ref); 127 } 128 129 static void axi_i2s_shutdown(struct snd_pcm_substream *substream, 130 struct snd_soc_dai *dai) 131 { 132 struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai); 133 134 clk_disable_unprepare(i2s->clk_ref); 135 } 136 137 static int axi_i2s_dai_probe(struct snd_soc_dai *dai) 138 { 139 struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai); 140 141 snd_soc_dai_init_dma_data( 142 dai, 143 i2s->has_playback ? &i2s->playback_dma_data : NULL, 144 i2s->has_capture ? &i2s->capture_dma_data : NULL); 145 146 return 0; 147 } 148 149 static const struct snd_soc_dai_ops axi_i2s_dai_ops = { 150 .startup = axi_i2s_startup, 151 .shutdown = axi_i2s_shutdown, 152 .trigger = axi_i2s_trigger, 153 .hw_params = axi_i2s_hw_params, 154 }; 155 156 static struct snd_soc_dai_driver axi_i2s_dai = { 157 .probe = axi_i2s_dai_probe, 158 .ops = &axi_i2s_dai_ops, 159 .symmetric_rates = 1, 160 }; 161 162 static const struct snd_soc_component_driver axi_i2s_component = { 163 .name = "axi-i2s", 164 }; 165 166 static const struct regmap_config axi_i2s_regmap_config = { 167 .reg_bits = 32, 168 .reg_stride = 4, 169 .val_bits = 32, 170 .max_register = AXI_I2S_REG_STATUS, 171 }; 172 173 static void axi_i2s_parse_of(struct axi_i2s *i2s, const struct device_node *np) 174 { 175 struct property *dma_names; 176 const char *dma_name; 177 178 of_property_for_each_string(np, "dma-names", dma_names, dma_name) { 179 if (strcmp(dma_name, "rx") == 0) 180 i2s->has_capture = true; 181 if (strcmp(dma_name, "tx") == 0) 182 i2s->has_playback = true; 183 } 184 } 185 186 static int axi_i2s_probe(struct platform_device *pdev) 187 { 188 struct resource *res; 189 struct axi_i2s *i2s; 190 void __iomem *base; 191 int ret; 192 193 i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL); 194 if (!i2s) 195 return -ENOMEM; 196 197 platform_set_drvdata(pdev, i2s); 198 199 axi_i2s_parse_of(i2s, pdev->dev.of_node); 200 201 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 202 base = devm_ioremap_resource(&pdev->dev, res); 203 if (IS_ERR(base)) 204 return PTR_ERR(base); 205 206 i2s->regmap = devm_regmap_init_mmio(&pdev->dev, base, 207 &axi_i2s_regmap_config); 208 if (IS_ERR(i2s->regmap)) 209 return PTR_ERR(i2s->regmap); 210 211 i2s->clk = devm_clk_get(&pdev->dev, "axi"); 212 if (IS_ERR(i2s->clk)) 213 return PTR_ERR(i2s->clk); 214 215 i2s->clk_ref = devm_clk_get(&pdev->dev, "ref"); 216 if (IS_ERR(i2s->clk_ref)) 217 return PTR_ERR(i2s->clk_ref); 218 219 ret = clk_prepare_enable(i2s->clk); 220 if (ret) 221 return ret; 222 223 if (i2s->has_playback) { 224 axi_i2s_dai.playback.channels_min = 2; 225 axi_i2s_dai.playback.channels_max = 2; 226 axi_i2s_dai.playback.rates = SNDRV_PCM_RATE_KNOT; 227 axi_i2s_dai.playback.formats = 228 SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE; 229 230 i2s->playback_dma_data.addr = res->start + AXI_I2S_REG_TX_FIFO; 231 i2s->playback_dma_data.addr_width = 4; 232 i2s->playback_dma_data.maxburst = 1; 233 } 234 235 if (i2s->has_capture) { 236 axi_i2s_dai.capture.channels_min = 2; 237 axi_i2s_dai.capture.channels_max = 2; 238 axi_i2s_dai.capture.rates = SNDRV_PCM_RATE_KNOT; 239 axi_i2s_dai.capture.formats = 240 SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE; 241 242 i2s->capture_dma_data.addr = res->start + AXI_I2S_REG_RX_FIFO; 243 i2s->capture_dma_data.addr_width = 4; 244 i2s->capture_dma_data.maxburst = 1; 245 } 246 247 i2s->ratnum.num = clk_get_rate(i2s->clk_ref) / 2 / AXI_I2S_BITS_PER_FRAME; 248 i2s->ratnum.den_step = 1; 249 i2s->ratnum.den_min = 1; 250 i2s->ratnum.den_max = 64; 251 252 i2s->rate_constraints.rats = &i2s->ratnum; 253 i2s->rate_constraints.nrats = 1; 254 255 regmap_write(i2s->regmap, AXI_I2S_REG_RESET, AXI_I2S_RESET_GLOBAL); 256 257 ret = devm_snd_soc_register_component(&pdev->dev, &axi_i2s_component, 258 &axi_i2s_dai, 1); 259 if (ret) 260 goto err_clk_disable; 261 262 ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0); 263 if (ret) 264 goto err_clk_disable; 265 266 dev_info(&pdev->dev, "probed, capture %s, playback %s\n", 267 i2s->has_capture ? "enabled" : "disabled", 268 i2s->has_playback ? "enabled" : "disabled"); 269 270 return 0; 271 272 err_clk_disable: 273 clk_disable_unprepare(i2s->clk); 274 return ret; 275 } 276 277 static int axi_i2s_dev_remove(struct platform_device *pdev) 278 { 279 struct axi_i2s *i2s = platform_get_drvdata(pdev); 280 281 clk_disable_unprepare(i2s->clk); 282 283 return 0; 284 } 285 286 static const struct of_device_id axi_i2s_of_match[] = { 287 { .compatible = "adi,axi-i2s-1.00.a", }, 288 {}, 289 }; 290 MODULE_DEVICE_TABLE(of, axi_i2s_of_match); 291 292 static struct platform_driver axi_i2s_driver = { 293 .driver = { 294 .name = "axi-i2s", 295 .of_match_table = axi_i2s_of_match, 296 }, 297 .probe = axi_i2s_probe, 298 .remove = axi_i2s_dev_remove, 299 }; 300 module_platform_driver(axi_i2s_driver); 301 302 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); 303 MODULE_DESCRIPTION("AXI I2S driver"); 304 MODULE_LICENSE("GPL"); 305