1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Xilinx ASoC SPDIF audio support
4 //
5 // Copyright (C) 2018 Xilinx, Inc.
6 //
7 // Author: Maruthi Srinivas Bayyavarapu <maruthis@xilinx.com>
8 //
9
10 #include <linux/clk.h>
11 #include <linux/io.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/of_platform.h>
15 #include <linux/platform_device.h>
16 #include <sound/pcm_params.h>
17 #include <sound/soc.h>
18
19 #define XLNX_SPDIF_RATES \
20 (SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000 | \
21 SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000 | SNDRV_PCM_RATE_176400 | \
22 SNDRV_PCM_RATE_192000)
23
24 #define XLNX_SPDIF_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_LE)
25
26 #define XSPDIF_IRQ_STS_REG 0x20
27 #define XSPDIF_IRQ_ENABLE_REG 0x28
28 #define XSPDIF_SOFT_RESET_REG 0x40
29 #define XSPDIF_CONTROL_REG 0x44
30 #define XSPDIF_CHAN_0_STS_REG 0x4C
31 #define XSPDIF_GLOBAL_IRQ_ENABLE_REG 0x1C
32 #define XSPDIF_CH_A_USER_DATA_REG_0 0x64
33
34 #define XSPDIF_CORE_ENABLE_MASK BIT(0)
35 #define XSPDIF_FIFO_FLUSH_MASK BIT(1)
36 #define XSPDIF_CH_STS_MASK BIT(5)
37 #define XSPDIF_GLOBAL_IRQ_ENABLE BIT(31)
38 #define XSPDIF_CLOCK_CONFIG_BITS_MASK GENMASK(5, 2)
39 #define XSPDIF_CLOCK_CONFIG_BITS_SHIFT 2
40 #define XSPDIF_SOFT_RESET_VALUE 0xA
41
42 #define MAX_CHANNELS 2
43 #define AES_SAMPLE_WIDTH 32
44 #define CH_STATUS_UPDATE_TIMEOUT 40
45
46 struct spdif_dev_data {
47 u32 mode;
48 u32 aclk;
49 bool rx_chsts_updated;
50 void __iomem *base;
51 struct clk *axi_clk;
52 wait_queue_head_t chsts_q;
53 };
54
55 static irqreturn_t xlnx_spdifrx_irq_handler(int irq, void *arg)
56 {
57 u32 val;
58 struct spdif_dev_data *ctx = arg;
59
60 val = readl(ctx->base + XSPDIF_IRQ_STS_REG);
61 if (val & XSPDIF_CH_STS_MASK) {
62 writel(val & XSPDIF_CH_STS_MASK,
63 ctx->base + XSPDIF_IRQ_STS_REG);
64 val = readl(ctx->base +
65 XSPDIF_IRQ_ENABLE_REG);
66 writel(val & ~XSPDIF_CH_STS_MASK,
67 ctx->base + XSPDIF_IRQ_ENABLE_REG);
68
69 ctx->rx_chsts_updated = true;
70 wake_up_interruptible(&ctx->chsts_q);
71 return IRQ_HANDLED;
72 }
73
74 return IRQ_NONE;
75 }
76
77 static int xlnx_spdif_startup(struct snd_pcm_substream *substream,
78 struct snd_soc_dai *dai)
79 {
80 u32 val;
81 struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
82
83 val = readl(ctx->base + XSPDIF_CONTROL_REG);
84 val |= XSPDIF_FIFO_FLUSH_MASK;
85 writel(val, ctx->base + XSPDIF_CONTROL_REG);
86
87 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
88 writel(XSPDIF_CH_STS_MASK,
89 ctx->base + XSPDIF_IRQ_ENABLE_REG);
90 writel(XSPDIF_GLOBAL_IRQ_ENABLE,
91 ctx->base + XSPDIF_GLOBAL_IRQ_ENABLE_REG);
92 }
93
94 return 0;
95 }
96
97 static void xlnx_spdif_shutdown(struct snd_pcm_substream *substream,
98 struct snd_soc_dai *dai)
99 {
100 struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
101
102 writel(XSPDIF_SOFT_RESET_VALUE, ctx->base + XSPDIF_SOFT_RESET_REG);
103 }
104
105 static int xlnx_spdif_hw_params(struct snd_pcm_substream *substream,
106 struct snd_pcm_hw_params *params,
107 struct snd_soc_dai *dai)
108 {
109 u32 val, clk_div, clk_cfg;
110 struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
111
112 clk_div = DIV_ROUND_CLOSEST(ctx->aclk, MAX_CHANNELS * AES_SAMPLE_WIDTH *
113 params_rate(params));
114
115 switch (clk_div) {
116 case 4:
117 clk_cfg = 0;
118 break;
119 case 8:
120 clk_cfg = 1;
121 break;
122 case 16:
123 clk_cfg = 2;
124 break;
125 case 24:
126 clk_cfg = 3;
127 break;
128 case 32:
129 clk_cfg = 4;
130 break;
131 case 48:
132 clk_cfg = 5;
133 break;
134 case 64:
135 clk_cfg = 6;
136 break;
137 default:
138 return -EINVAL;
139 }
140
141 val = readl(ctx->base + XSPDIF_CONTROL_REG);
142 val &= ~XSPDIF_CLOCK_CONFIG_BITS_MASK;
143 val |= clk_cfg << XSPDIF_CLOCK_CONFIG_BITS_SHIFT;
144 writel(val, ctx->base + XSPDIF_CONTROL_REG);
145
146 return 0;
147 }
148
149 static int rx_stream_detect(struct snd_soc_dai *dai)
150 {
151 int err;
152 struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
153 unsigned long jiffies = msecs_to_jiffies(CH_STATUS_UPDATE_TIMEOUT);
154
155 /* start capture only if stream is detected within 40ms timeout */
156 err = wait_event_interruptible_timeout(ctx->chsts_q,
157 ctx->rx_chsts_updated,
158 jiffies);
159 if (!err) {
160 dev_err(dai->dev, "No streaming audio detected!\n");
161 return -EINVAL;
162 }
163 ctx->rx_chsts_updated = false;
164
165 return 0;
166 }
167
168 static int xlnx_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
169 struct snd_soc_dai *dai)
170 {
171 u32 val;
172 int ret = 0;
173 struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
174
175 val = readl(ctx->base + XSPDIF_CONTROL_REG);
176 switch (cmd) {
177 case SNDRV_PCM_TRIGGER_START:
178 case SNDRV_PCM_TRIGGER_RESUME:
179 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
180 val |= XSPDIF_CORE_ENABLE_MASK;
181 writel(val, ctx->base + XSPDIF_CONTROL_REG);
182 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
183 ret = rx_stream_detect(dai);
184 break;
185 case SNDRV_PCM_TRIGGER_STOP:
186 case SNDRV_PCM_TRIGGER_SUSPEND:
187 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
188 val &= ~XSPDIF_CORE_ENABLE_MASK;
189 writel(val, ctx->base + XSPDIF_CONTROL_REG);
190 break;
191 default:
192 ret = -EINVAL;
193 }
194
195 return ret;
196 }
197
198 static const struct snd_soc_dai_ops xlnx_spdif_dai_ops = {
199 .startup = xlnx_spdif_startup,
200 .shutdown = xlnx_spdif_shutdown,
201 .trigger = xlnx_spdif_trigger,
202 .hw_params = xlnx_spdif_hw_params,
203 };
204
205 static struct snd_soc_dai_driver xlnx_spdif_tx_dai = {
206 .name = "xlnx_spdif_tx",
207 .playback = {
208 .channels_min = 2,
209 .channels_max = 2,
210 .rates = XLNX_SPDIF_RATES,
211 .formats = XLNX_SPDIF_FORMATS,
212 },
213 .ops = &xlnx_spdif_dai_ops,
214 };
215
216 static struct snd_soc_dai_driver xlnx_spdif_rx_dai = {
217 .name = "xlnx_spdif_rx",
218 .capture = {
219 .channels_min = 2,
220 .channels_max = 2,
221 .rates = XLNX_SPDIF_RATES,
222 .formats = XLNX_SPDIF_FORMATS,
223 },
224 .ops = &xlnx_spdif_dai_ops,
225 };
226
227 static const struct snd_soc_component_driver xlnx_spdif_component = {
228 .name = "xlnx-spdif",
229 .legacy_dai_naming = 1,
230 };
231
232 static const struct of_device_id xlnx_spdif_of_match[] = {
233 { .compatible = "xlnx,spdif-2.0", },
234 {},
235 };
236 MODULE_DEVICE_TABLE(of, xlnx_spdif_of_match);
237
238 static int xlnx_spdif_probe(struct platform_device *pdev)
239 {
240 int ret;
241 struct snd_soc_dai_driver *dai_drv;
242 struct spdif_dev_data *ctx;
243
244 struct device *dev = &pdev->dev;
245 struct device_node *node = dev->of_node;
246
247 ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
248 if (!ctx)
249 return -ENOMEM;
250
251 ctx->axi_clk = devm_clk_get(dev, "s_axi_aclk");
252 if (IS_ERR(ctx->axi_clk)) {
253 ret = PTR_ERR(ctx->axi_clk);
254 dev_err(dev, "failed to get s_axi_aclk(%d)\n", ret);
255 return ret;
256 }
257 ret = clk_prepare_enable(ctx->axi_clk);
258 if (ret) {
259 dev_err(dev, "failed to enable s_axi_aclk(%d)\n", ret);
260 return ret;
261 }
262
263 ctx->base = devm_platform_ioremap_resource(pdev, 0);
264 if (IS_ERR(ctx->base)) {
265 ret = PTR_ERR(ctx->base);
266 goto clk_err;
267 }
268 ret = of_property_read_u32(node, "xlnx,spdif-mode", &ctx->mode);
269 if (ret < 0) {
270 dev_err(dev, "cannot get SPDIF mode\n");
271 goto clk_err;
272 }
273 if (ctx->mode) {
274 dai_drv = &xlnx_spdif_tx_dai;
275 } else {
276 ret = platform_get_irq(pdev, 0);
277 if (ret < 0)
278 goto clk_err;
279 ret = devm_request_irq(dev, ret,
280 xlnx_spdifrx_irq_handler,
281 0, "XLNX_SPDIF_RX", ctx);
282 if (ret) {
283 dev_err(dev, "spdif rx irq request failed\n");
284 ret = -ENODEV;
285 goto clk_err;
286 }
287
288 init_waitqueue_head(&ctx->chsts_q);
289 dai_drv = &xlnx_spdif_rx_dai;
290 }
291
292 ret = of_property_read_u32(node, "xlnx,aud_clk_i", &ctx->aclk);
293 if (ret < 0) {
294 dev_err(dev, "cannot get aud_clk_i value\n");
295 goto clk_err;
296 }
297
298 dev_set_drvdata(dev, ctx);
299
300 ret = devm_snd_soc_register_component(dev, &xlnx_spdif_component,
301 dai_drv, 1);
302 if (ret) {
303 dev_err(dev, "SPDIF component registration failed\n");
304 goto clk_err;
305 }
306
307 writel(XSPDIF_SOFT_RESET_VALUE, ctx->base + XSPDIF_SOFT_RESET_REG);
308 dev_info(dev, "%s DAI registered\n", dai_drv->name);
309
310 clk_err:
311 clk_disable_unprepare(ctx->axi_clk);
312 return ret;
313 }
314
315 static void xlnx_spdif_remove(struct platform_device *pdev)
316 {
317 struct spdif_dev_data *ctx = dev_get_drvdata(&pdev->dev);
318
319 clk_disable_unprepare(ctx->axi_clk);
320 }
321
322 static struct platform_driver xlnx_spdif_driver = {
323 .driver = {
324 .name = "xlnx-spdif",
325 .of_match_table = xlnx_spdif_of_match,
326 },
327 .probe = xlnx_spdif_probe,
328 .remove_new = xlnx_spdif_remove,
329 };
330 module_platform_driver(xlnx_spdif_driver);
331
332 MODULE_AUTHOR("Maruthi Srinivas Bayyavarapu <maruthis@xilinx.com>");
333 MODULE_DESCRIPTION("XILINX SPDIF driver");
334 MODULE_LICENSE("GPL v2");
335
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