xref: /linux/sound/soc/meson/axg-fifo.c (revision 864cee90d4bd870e5d5e5a0b1a6f055f4f951350)
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 	unsigned int burst_num, period, threshold;
117 	dma_addr_t end_ptr;
118 
119 	period = params_period_bytes(params);
120 
121 	/* Setup dma memory pointers */
122 	end_ptr = runtime->dma_addr + runtime->dma_bytes - AXG_FIFO_BURST;
123 	regmap_write(fifo->map, FIFO_START_ADDR, runtime->dma_addr);
124 	regmap_write(fifo->map, FIFO_FINISH_ADDR, end_ptr);
125 
126 	/* Setup interrupt periodicity */
127 	burst_num = period / AXG_FIFO_BURST;
128 	regmap_write(fifo->map, FIFO_INT_ADDR, burst_num);
129 
130 	/*
131 	 * Start the fifo request on the smallest of the following:
132 	 * - Half the fifo size
133 	 * - Half the period size
134 	 */
135 	threshold = min(period / 2,
136 			(unsigned int)AXG_FIFO_MIN_DEPTH / 2);
137 
138 	/*
139 	 * With the threshold in bytes, register value is:
140 	 * V = (threshold / burst) - 1
141 	 */
142 	threshold /= AXG_FIFO_BURST;
143 	regmap_field_write(fifo->field_threshold,
144 			   threshold ? threshold - 1 : 0);
145 
146 	/* Enable block count irq */
147 	regmap_update_bits(fifo->map, FIFO_CTRL0,
148 			   CTRL0_INT_EN(FIFO_INT_COUNT_REPEAT),
149 			   CTRL0_INT_EN(FIFO_INT_COUNT_REPEAT));
150 
151 	return 0;
152 }
153 EXPORT_SYMBOL_GPL(axg_fifo_pcm_hw_params);
154 
155 int g12a_fifo_pcm_hw_params(struct snd_soc_component *component,
156 			    struct snd_pcm_substream *ss,
157 			    struct snd_pcm_hw_params *params)
158 {
159 	struct axg_fifo *fifo = axg_fifo_data(ss);
160 	struct snd_pcm_runtime *runtime = ss->runtime;
161 	int ret;
162 
163 	ret = axg_fifo_pcm_hw_params(component, ss, params);
164 	if (ret)
165 		return ret;
166 
167 	/* Set the initial memory address of the DMA */
168 	regmap_write(fifo->map, FIFO_INIT_ADDR, runtime->dma_addr);
169 
170 	return 0;
171 }
172 EXPORT_SYMBOL_GPL(g12a_fifo_pcm_hw_params);
173 
174 int axg_fifo_pcm_hw_free(struct snd_soc_component *component,
175 			 struct snd_pcm_substream *ss)
176 {
177 	struct axg_fifo *fifo = axg_fifo_data(ss);
178 
179 	/* Disable the block count irq */
180 	regmap_update_bits(fifo->map, FIFO_CTRL0,
181 			   CTRL0_INT_EN(FIFO_INT_COUNT_REPEAT), 0);
182 
183 	return 0;
184 }
185 EXPORT_SYMBOL_GPL(axg_fifo_pcm_hw_free);
186 
187 static void axg_fifo_ack_irq(struct axg_fifo *fifo, u8 mask)
188 {
189 	regmap_update_bits(fifo->map, FIFO_CTRL1,
190 			   CTRL1_INT_CLR(FIFO_INT_MASK),
191 			   CTRL1_INT_CLR(mask));
192 
193 	/* Clear must also be cleared */
194 	regmap_update_bits(fifo->map, FIFO_CTRL1,
195 			   CTRL1_INT_CLR(FIFO_INT_MASK),
196 			   0);
197 }
198 
199 static irqreturn_t axg_fifo_pcm_irq_block(int irq, void *dev_id)
200 {
201 	struct snd_pcm_substream *ss = dev_id;
202 	struct axg_fifo *fifo = axg_fifo_data(ss);
203 	unsigned int status;
204 
205 	regmap_read(fifo->map, FIFO_STATUS1, &status);
206 
207 	status = STATUS1_INT_STS(status) & FIFO_INT_MASK;
208 	if (status & FIFO_INT_COUNT_REPEAT)
209 		snd_pcm_period_elapsed(ss);
210 	else
211 		dev_dbg(axg_fifo_dev(ss), "unexpected irq - STS 0x%02x\n",
212 			status);
213 
214 	/* Ack irqs */
215 	axg_fifo_ack_irq(fifo, status);
216 
217 	return IRQ_RETVAL(status);
218 }
219 
220 int axg_fifo_pcm_open(struct snd_soc_component *component,
221 		      struct snd_pcm_substream *ss)
222 {
223 	struct axg_fifo *fifo = axg_fifo_data(ss);
224 	struct device *dev = axg_fifo_dev(ss);
225 	int ret;
226 
227 	snd_soc_set_runtime_hwparams(ss, &axg_fifo_hw);
228 
229 	/*
230 	 * Make sure the buffer and period size are multiple of the FIFO
231 	 * minimum depth size
232 	 */
233 	ret = snd_pcm_hw_constraint_step(ss->runtime, 0,
234 					 SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
235 					 AXG_FIFO_MIN_DEPTH);
236 	if (ret)
237 		return ret;
238 
239 	ret = snd_pcm_hw_constraint_step(ss->runtime, 0,
240 					 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
241 					 AXG_FIFO_MIN_DEPTH);
242 	if (ret)
243 		return ret;
244 
245 	ret = request_irq(fifo->irq, axg_fifo_pcm_irq_block, 0,
246 			  dev_name(dev), ss);
247 	if (ret)
248 		return ret;
249 
250 	/* Enable pclk to access registers and clock the fifo ip */
251 	ret = clk_prepare_enable(fifo->pclk);
252 	if (ret)
253 		return ret;
254 
255 	/* Setup status2 so it reports the memory pointer */
256 	regmap_update_bits(fifo->map, FIFO_CTRL1,
257 			   CTRL1_STATUS2_SEL_MASK,
258 			   CTRL1_STATUS2_SEL(STATUS2_SEL_DDR_READ));
259 
260 	/* Make sure the dma is initially disabled */
261 	__dma_enable(fifo, false);
262 
263 	/* Disable irqs until params are ready */
264 	regmap_update_bits(fifo->map, FIFO_CTRL0,
265 			   CTRL0_INT_EN(FIFO_INT_MASK), 0);
266 
267 	/* Clear any pending interrupt */
268 	axg_fifo_ack_irq(fifo, FIFO_INT_MASK);
269 
270 	/* Take memory arbitror out of reset */
271 	ret = reset_control_deassert(fifo->arb);
272 	if (ret)
273 		clk_disable_unprepare(fifo->pclk);
274 
275 	return ret;
276 }
277 EXPORT_SYMBOL_GPL(axg_fifo_pcm_open);
278 
279 int axg_fifo_pcm_close(struct snd_soc_component *component,
280 		       struct snd_pcm_substream *ss)
281 {
282 	struct axg_fifo *fifo = axg_fifo_data(ss);
283 	int ret;
284 
285 	/* Put the memory arbitror back in reset */
286 	ret = reset_control_assert(fifo->arb);
287 
288 	/* Disable fifo ip and register access */
289 	clk_disable_unprepare(fifo->pclk);
290 
291 	/* remove IRQ */
292 	free_irq(fifo->irq, ss);
293 
294 	return ret;
295 }
296 EXPORT_SYMBOL_GPL(axg_fifo_pcm_close);
297 
298 int axg_fifo_pcm_new(struct snd_soc_pcm_runtime *rtd, unsigned int type)
299 {
300 	struct snd_card *card = rtd->card->snd_card;
301 	size_t size = axg_fifo_hw.buffer_bytes_max;
302 
303 	snd_pcm_set_managed_buffer(rtd->pcm->streams[type].substream,
304 				   SNDRV_DMA_TYPE_DEV, card->dev,
305 				   size, size);
306 	return 0;
307 }
308 EXPORT_SYMBOL_GPL(axg_fifo_pcm_new);
309 
310 static const struct regmap_config axg_fifo_regmap_cfg = {
311 	.reg_bits	= 32,
312 	.val_bits	= 32,
313 	.reg_stride	= 4,
314 	.max_register	= FIFO_CTRL2,
315 };
316 
317 int axg_fifo_probe(struct platform_device *pdev)
318 {
319 	struct device *dev = &pdev->dev;
320 	const struct axg_fifo_match_data *data;
321 	struct axg_fifo *fifo;
322 	void __iomem *regs;
323 
324 	data = of_device_get_match_data(dev);
325 	if (!data) {
326 		dev_err(dev, "failed to match device\n");
327 		return -ENODEV;
328 	}
329 
330 	fifo = devm_kzalloc(dev, sizeof(*fifo), GFP_KERNEL);
331 	if (!fifo)
332 		return -ENOMEM;
333 	platform_set_drvdata(pdev, fifo);
334 
335 	regs = devm_platform_ioremap_resource(pdev, 0);
336 	if (IS_ERR(regs))
337 		return PTR_ERR(regs);
338 
339 	fifo->map = devm_regmap_init_mmio(dev, regs, &axg_fifo_regmap_cfg);
340 	if (IS_ERR(fifo->map)) {
341 		dev_err(dev, "failed to init regmap: %ld\n",
342 			PTR_ERR(fifo->map));
343 		return PTR_ERR(fifo->map);
344 	}
345 
346 	fifo->pclk = devm_clk_get(dev, NULL);
347 	if (IS_ERR(fifo->pclk)) {
348 		if (PTR_ERR(fifo->pclk) != -EPROBE_DEFER)
349 			dev_err(dev, "failed to get pclk: %ld\n",
350 				PTR_ERR(fifo->pclk));
351 		return PTR_ERR(fifo->pclk);
352 	}
353 
354 	fifo->arb = devm_reset_control_get_exclusive(dev, NULL);
355 	if (IS_ERR(fifo->arb)) {
356 		if (PTR_ERR(fifo->arb) != -EPROBE_DEFER)
357 			dev_err(dev, "failed to get arb reset: %ld\n",
358 				PTR_ERR(fifo->arb));
359 		return PTR_ERR(fifo->arb);
360 	}
361 
362 	fifo->irq = of_irq_get(dev->of_node, 0);
363 	if (fifo->irq <= 0) {
364 		dev_err(dev, "failed to get irq: %d\n", fifo->irq);
365 		return fifo->irq;
366 	}
367 
368 	fifo->field_threshold =
369 		devm_regmap_field_alloc(dev, fifo->map, data->field_threshold);
370 	if (IS_ERR(fifo->field_threshold))
371 		return PTR_ERR(fifo->field_threshold);
372 
373 	return devm_snd_soc_register_component(dev, data->component_drv,
374 					       data->dai_drv, 1);
375 }
376 EXPORT_SYMBOL_GPL(axg_fifo_probe);
377 
378 MODULE_DESCRIPTION("Amlogic AXG/G12A fifo driver");
379 MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
380 MODULE_LICENSE("GPL v2");
381