xref: /linux/sound/soc/meson/axg-fifo.c (revision bace3caa82e1f0b5b667e35b532534b9cbdc4338)
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/of_irq.h>
8 #include <linux/of_platform.h>
9 #include <linux/module.h>
10 #include <linux/regmap.h>
11 #include <linux/reset.h>
12 #include <sound/pcm_params.h>
13 #include <sound/soc.h>
14 #include <sound/soc-dai.h>
15 
16 #include "axg-fifo.h"
17 
18 /*
19  * This file implements the platform operations common to the playback and
20  * capture frontend DAI. The logic behind this two types of fifo is very
21  * similar but some difference exist.
22  * These differences are handled in the respective DAI drivers
23  */
24 
25 static struct snd_pcm_hardware axg_fifo_hw = {
26 	.info = (SNDRV_PCM_INFO_INTERLEAVED |
27 		 SNDRV_PCM_INFO_MMAP |
28 		 SNDRV_PCM_INFO_MMAP_VALID |
29 		 SNDRV_PCM_INFO_BLOCK_TRANSFER |
30 		 SNDRV_PCM_INFO_PAUSE),
31 
32 	.formats = AXG_FIFO_FORMATS,
33 	.rate_min = 5512,
34 	.rate_max = 192000,
35 	.channels_min = 1,
36 	.channels_max = AXG_FIFO_CH_MAX,
37 	.period_bytes_min = AXG_FIFO_MIN_DEPTH,
38 	.period_bytes_max = UINT_MAX,
39 	.periods_min = 2,
40 	.periods_max = UINT_MAX,
41 
42 	/* No real justification for this */
43 	.buffer_bytes_max = 1 * 1024 * 1024,
44 };
45 
46 static struct snd_soc_dai *axg_fifo_dai(struct snd_pcm_substream *ss)
47 {
48 	struct snd_soc_pcm_runtime *rtd = ss->private_data;
49 
50 	return rtd->cpu_dai;
51 }
52 
53 static struct axg_fifo *axg_fifo_data(struct snd_pcm_substream *ss)
54 {
55 	struct snd_soc_dai *dai = axg_fifo_dai(ss);
56 
57 	return snd_soc_dai_get_drvdata(dai);
58 }
59 
60 static struct device *axg_fifo_dev(struct snd_pcm_substream *ss)
61 {
62 	struct snd_soc_dai *dai = axg_fifo_dai(ss);
63 
64 	return dai->dev;
65 }
66 
67 static void __dma_enable(struct axg_fifo *fifo,  bool enable)
68 {
69 	regmap_update_bits(fifo->map, FIFO_CTRL0, CTRL0_DMA_EN,
70 			   enable ? CTRL0_DMA_EN : 0);
71 }
72 
73 int axg_fifo_pcm_trigger(struct snd_soc_component *component,
74 			 struct snd_pcm_substream *ss, int cmd)
75 {
76 	struct axg_fifo *fifo = axg_fifo_data(ss);
77 
78 	switch (cmd) {
79 	case SNDRV_PCM_TRIGGER_START:
80 	case SNDRV_PCM_TRIGGER_RESUME:
81 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
82 		__dma_enable(fifo, true);
83 		break;
84 	case SNDRV_PCM_TRIGGER_SUSPEND:
85 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
86 	case SNDRV_PCM_TRIGGER_STOP:
87 		__dma_enable(fifo, false);
88 		break;
89 	default:
90 		return -EINVAL;
91 	}
92 
93 	return 0;
94 }
95 EXPORT_SYMBOL_GPL(axg_fifo_pcm_trigger);
96 
97 snd_pcm_uframes_t axg_fifo_pcm_pointer(struct snd_soc_component *component,
98 				       struct snd_pcm_substream *ss)
99 {
100 	struct axg_fifo *fifo = axg_fifo_data(ss);
101 	struct snd_pcm_runtime *runtime = ss->runtime;
102 	unsigned int addr;
103 
104 	regmap_read(fifo->map, FIFO_STATUS2, &addr);
105 
106 	return bytes_to_frames(runtime, addr - (unsigned int)runtime->dma_addr);
107 }
108 EXPORT_SYMBOL_GPL(axg_fifo_pcm_pointer);
109 
110 int axg_fifo_pcm_hw_params(struct snd_soc_component *component,
111 			   struct snd_pcm_substream *ss,
112 			   struct snd_pcm_hw_params *params)
113 {
114 	struct snd_pcm_runtime *runtime = ss->runtime;
115 	struct axg_fifo *fifo = axg_fifo_data(ss);
116 	dma_addr_t end_ptr;
117 	unsigned int burst_num;
118 
119 	/* Setup dma memory pointers */
120 	end_ptr = runtime->dma_addr + runtime->dma_bytes - AXG_FIFO_BURST;
121 	regmap_write(fifo->map, FIFO_START_ADDR, runtime->dma_addr);
122 	regmap_write(fifo->map, FIFO_FINISH_ADDR, end_ptr);
123 
124 	/* Setup interrupt periodicity */
125 	burst_num = params_period_bytes(params) / AXG_FIFO_BURST;
126 	regmap_write(fifo->map, FIFO_INT_ADDR, burst_num);
127 
128 	/* Enable block count irq */
129 	regmap_update_bits(fifo->map, FIFO_CTRL0,
130 			   CTRL0_INT_EN(FIFO_INT_COUNT_REPEAT),
131 			   CTRL0_INT_EN(FIFO_INT_COUNT_REPEAT));
132 
133 	return 0;
134 }
135 EXPORT_SYMBOL_GPL(axg_fifo_pcm_hw_params);
136 
137 int g12a_fifo_pcm_hw_params(struct snd_soc_component *component,
138 			    struct snd_pcm_substream *ss,
139 			    struct snd_pcm_hw_params *params)
140 {
141 	struct axg_fifo *fifo = axg_fifo_data(ss);
142 	struct snd_pcm_runtime *runtime = ss->runtime;
143 	int ret;
144 
145 	ret = axg_fifo_pcm_hw_params(component, ss, params);
146 	if (ret)
147 		return ret;
148 
149 	/* Set the initial memory address of the DMA */
150 	regmap_write(fifo->map, FIFO_INIT_ADDR, runtime->dma_addr);
151 
152 	return 0;
153 }
154 EXPORT_SYMBOL_GPL(g12a_fifo_pcm_hw_params);
155 
156 int axg_fifo_pcm_hw_free(struct snd_soc_component *component,
157 			 struct snd_pcm_substream *ss)
158 {
159 	struct axg_fifo *fifo = axg_fifo_data(ss);
160 
161 	/* Disable the block count irq */
162 	regmap_update_bits(fifo->map, FIFO_CTRL0,
163 			   CTRL0_INT_EN(FIFO_INT_COUNT_REPEAT), 0);
164 
165 	return 0;
166 }
167 EXPORT_SYMBOL_GPL(axg_fifo_pcm_hw_free);
168 
169 static void axg_fifo_ack_irq(struct axg_fifo *fifo, u8 mask)
170 {
171 	regmap_update_bits(fifo->map, FIFO_CTRL1,
172 			   CTRL1_INT_CLR(FIFO_INT_MASK),
173 			   CTRL1_INT_CLR(mask));
174 
175 	/* Clear must also be cleared */
176 	regmap_update_bits(fifo->map, FIFO_CTRL1,
177 			   CTRL1_INT_CLR(FIFO_INT_MASK),
178 			   0);
179 }
180 
181 static irqreturn_t axg_fifo_pcm_irq_block(int irq, void *dev_id)
182 {
183 	struct snd_pcm_substream *ss = dev_id;
184 	struct axg_fifo *fifo = axg_fifo_data(ss);
185 	unsigned int status;
186 
187 	regmap_read(fifo->map, FIFO_STATUS1, &status);
188 
189 	status = STATUS1_INT_STS(status) & FIFO_INT_MASK;
190 	if (status & FIFO_INT_COUNT_REPEAT)
191 		snd_pcm_period_elapsed(ss);
192 	else
193 		dev_dbg(axg_fifo_dev(ss), "unexpected irq - STS 0x%02x\n",
194 			status);
195 
196 	/* Ack irqs */
197 	axg_fifo_ack_irq(fifo, status);
198 
199 	return IRQ_RETVAL(status);
200 }
201 
202 int axg_fifo_pcm_open(struct snd_soc_component *component,
203 		      struct snd_pcm_substream *ss)
204 {
205 	struct axg_fifo *fifo = axg_fifo_data(ss);
206 	struct device *dev = axg_fifo_dev(ss);
207 	int ret;
208 
209 	snd_soc_set_runtime_hwparams(ss, &axg_fifo_hw);
210 
211 	/*
212 	 * Make sure the buffer and period size are multiple of the FIFO
213 	 * minimum depth size
214 	 */
215 	ret = snd_pcm_hw_constraint_step(ss->runtime, 0,
216 					 SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
217 					 AXG_FIFO_MIN_DEPTH);
218 	if (ret)
219 		return ret;
220 
221 	ret = snd_pcm_hw_constraint_step(ss->runtime, 0,
222 					 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
223 					 AXG_FIFO_MIN_DEPTH);
224 	if (ret)
225 		return ret;
226 
227 	ret = request_irq(fifo->irq, axg_fifo_pcm_irq_block, 0,
228 			  dev_name(dev), ss);
229 	if (ret)
230 		return ret;
231 
232 	/* Enable pclk to access registers and clock the fifo ip */
233 	ret = clk_prepare_enable(fifo->pclk);
234 	if (ret)
235 		return ret;
236 
237 	/* Setup status2 so it reports the memory pointer */
238 	regmap_update_bits(fifo->map, FIFO_CTRL1,
239 			   CTRL1_STATUS2_SEL_MASK,
240 			   CTRL1_STATUS2_SEL(STATUS2_SEL_DDR_READ));
241 
242 	/* Make sure the dma is initially disabled */
243 	__dma_enable(fifo, false);
244 
245 	/* Disable irqs until params are ready */
246 	regmap_update_bits(fifo->map, FIFO_CTRL0,
247 			   CTRL0_INT_EN(FIFO_INT_MASK), 0);
248 
249 	/* Clear any pending interrupt */
250 	axg_fifo_ack_irq(fifo, FIFO_INT_MASK);
251 
252 	/* Take memory arbitror out of reset */
253 	ret = reset_control_deassert(fifo->arb);
254 	if (ret)
255 		clk_disable_unprepare(fifo->pclk);
256 
257 	return ret;
258 }
259 EXPORT_SYMBOL_GPL(axg_fifo_pcm_open);
260 
261 int axg_fifo_pcm_close(struct snd_soc_component *component,
262 		       struct snd_pcm_substream *ss)
263 {
264 	struct axg_fifo *fifo = axg_fifo_data(ss);
265 	int ret;
266 
267 	/* Put the memory arbitror back in reset */
268 	ret = reset_control_assert(fifo->arb);
269 
270 	/* Disable fifo ip and register access */
271 	clk_disable_unprepare(fifo->pclk);
272 
273 	/* remove IRQ */
274 	free_irq(fifo->irq, ss);
275 
276 	return ret;
277 }
278 EXPORT_SYMBOL_GPL(axg_fifo_pcm_close);
279 
280 int axg_fifo_pcm_new(struct snd_soc_pcm_runtime *rtd, unsigned int type)
281 {
282 	struct snd_card *card = rtd->card->snd_card;
283 	size_t size = axg_fifo_hw.buffer_bytes_max;
284 
285 	snd_pcm_set_managed_buffer(rtd->pcm->streams[type].substream,
286 				   SNDRV_DMA_TYPE_DEV, card->dev,
287 				   size, size);
288 	return 0;
289 }
290 EXPORT_SYMBOL_GPL(axg_fifo_pcm_new);
291 
292 static const struct regmap_config axg_fifo_regmap_cfg = {
293 	.reg_bits	= 32,
294 	.val_bits	= 32,
295 	.reg_stride	= 4,
296 	.max_register	= FIFO_CTRL2,
297 };
298 
299 int axg_fifo_probe(struct platform_device *pdev)
300 {
301 	struct device *dev = &pdev->dev;
302 	const struct axg_fifo_match_data *data;
303 	struct axg_fifo *fifo;
304 	void __iomem *regs;
305 
306 	data = of_device_get_match_data(dev);
307 	if (!data) {
308 		dev_err(dev, "failed to match device\n");
309 		return -ENODEV;
310 	}
311 
312 	fifo = devm_kzalloc(dev, sizeof(*fifo), GFP_KERNEL);
313 	if (!fifo)
314 		return -ENOMEM;
315 	platform_set_drvdata(pdev, fifo);
316 
317 	regs = devm_platform_ioremap_resource(pdev, 0);
318 	if (IS_ERR(regs))
319 		return PTR_ERR(regs);
320 
321 	fifo->map = devm_regmap_init_mmio(dev, regs, &axg_fifo_regmap_cfg);
322 	if (IS_ERR(fifo->map)) {
323 		dev_err(dev, "failed to init regmap: %ld\n",
324 			PTR_ERR(fifo->map));
325 		return PTR_ERR(fifo->map);
326 	}
327 
328 	fifo->pclk = devm_clk_get(dev, NULL);
329 	if (IS_ERR(fifo->pclk)) {
330 		if (PTR_ERR(fifo->pclk) != -EPROBE_DEFER)
331 			dev_err(dev, "failed to get pclk: %ld\n",
332 				PTR_ERR(fifo->pclk));
333 		return PTR_ERR(fifo->pclk);
334 	}
335 
336 	fifo->arb = devm_reset_control_get_exclusive(dev, NULL);
337 	if (IS_ERR(fifo->arb)) {
338 		if (PTR_ERR(fifo->arb) != -EPROBE_DEFER)
339 			dev_err(dev, "failed to get arb reset: %ld\n",
340 				PTR_ERR(fifo->arb));
341 		return PTR_ERR(fifo->arb);
342 	}
343 
344 	fifo->irq = of_irq_get(dev->of_node, 0);
345 	if (fifo->irq <= 0) {
346 		dev_err(dev, "failed to get irq: %d\n", fifo->irq);
347 		return fifo->irq;
348 	}
349 
350 	return devm_snd_soc_register_component(dev, data->component_drv,
351 					       data->dai_drv, 1);
352 }
353 EXPORT_SYMBOL_GPL(axg_fifo_probe);
354 
355 MODULE_DESCRIPTION("Amlogic AXG/G12A fifo driver");
356 MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
357 MODULE_LICENSE("GPL v2");
358