xref: /openbmc/linux/sound/soc/meson/axg-fifo.c (revision e7253313)
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 	int ret;
119 
120 	ret = snd_pcm_lib_malloc_pages(ss, params_buffer_bytes(params));
121 	if (ret < 0)
122 		return ret;
123 
124 	/* Setup dma memory pointers */
125 	end_ptr = runtime->dma_addr + runtime->dma_bytes - AXG_FIFO_BURST;
126 	regmap_write(fifo->map, FIFO_START_ADDR, runtime->dma_addr);
127 	regmap_write(fifo->map, FIFO_FINISH_ADDR, end_ptr);
128 
129 	/* Setup interrupt periodicity */
130 	burst_num = params_period_bytes(params) / AXG_FIFO_BURST;
131 	regmap_write(fifo->map, FIFO_INT_ADDR, burst_num);
132 
133 	/* Enable block count irq */
134 	regmap_update_bits(fifo->map, FIFO_CTRL0,
135 			   CTRL0_INT_EN(FIFO_INT_COUNT_REPEAT),
136 			   CTRL0_INT_EN(FIFO_INT_COUNT_REPEAT));
137 
138 	return 0;
139 }
140 EXPORT_SYMBOL_GPL(axg_fifo_pcm_hw_params);
141 
142 int g12a_fifo_pcm_hw_params(struct snd_soc_component *component,
143 			    struct snd_pcm_substream *ss,
144 			    struct snd_pcm_hw_params *params)
145 {
146 	struct axg_fifo *fifo = axg_fifo_data(ss);
147 	struct snd_pcm_runtime *runtime = ss->runtime;
148 	int ret;
149 
150 	ret = axg_fifo_pcm_hw_params(component, ss, params);
151 	if (ret)
152 		return ret;
153 
154 	/* Set the initial memory address of the DMA */
155 	regmap_write(fifo->map, FIFO_INIT_ADDR, runtime->dma_addr);
156 
157 	return 0;
158 }
159 EXPORT_SYMBOL_GPL(g12a_fifo_pcm_hw_params);
160 
161 int axg_fifo_pcm_hw_free(struct snd_soc_component *component,
162 			 struct snd_pcm_substream *ss)
163 {
164 	struct axg_fifo *fifo = axg_fifo_data(ss);
165 
166 	/* Disable the block count irq */
167 	regmap_update_bits(fifo->map, FIFO_CTRL0,
168 			   CTRL0_INT_EN(FIFO_INT_COUNT_REPEAT), 0);
169 
170 	return snd_pcm_lib_free_pages(ss);
171 }
172 EXPORT_SYMBOL_GPL(axg_fifo_pcm_hw_free);
173 
174 static void axg_fifo_ack_irq(struct axg_fifo *fifo, u8 mask)
175 {
176 	regmap_update_bits(fifo->map, FIFO_CTRL1,
177 			   CTRL1_INT_CLR(FIFO_INT_MASK),
178 			   CTRL1_INT_CLR(mask));
179 
180 	/* Clear must also be cleared */
181 	regmap_update_bits(fifo->map, FIFO_CTRL1,
182 			   CTRL1_INT_CLR(FIFO_INT_MASK),
183 			   0);
184 }
185 
186 static irqreturn_t axg_fifo_pcm_irq_block(int irq, void *dev_id)
187 {
188 	struct snd_pcm_substream *ss = dev_id;
189 	struct axg_fifo *fifo = axg_fifo_data(ss);
190 	unsigned int status;
191 
192 	regmap_read(fifo->map, FIFO_STATUS1, &status);
193 
194 	status = STATUS1_INT_STS(status) & FIFO_INT_MASK;
195 	if (status & FIFO_INT_COUNT_REPEAT)
196 		snd_pcm_period_elapsed(ss);
197 	else
198 		dev_dbg(axg_fifo_dev(ss), "unexpected irq - STS 0x%02x\n",
199 			status);
200 
201 	/* Ack irqs */
202 	axg_fifo_ack_irq(fifo, status);
203 
204 	return IRQ_RETVAL(status);
205 }
206 
207 int axg_fifo_pcm_open(struct snd_soc_component *component,
208 		      struct snd_pcm_substream *ss)
209 {
210 	struct axg_fifo *fifo = axg_fifo_data(ss);
211 	struct device *dev = axg_fifo_dev(ss);
212 	int ret;
213 
214 	snd_soc_set_runtime_hwparams(ss, &axg_fifo_hw);
215 
216 	/*
217 	 * Make sure the buffer and period size are multiple of the FIFO
218 	 * minimum depth size
219 	 */
220 	ret = snd_pcm_hw_constraint_step(ss->runtime, 0,
221 					 SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
222 					 AXG_FIFO_MIN_DEPTH);
223 	if (ret)
224 		return ret;
225 
226 	ret = snd_pcm_hw_constraint_step(ss->runtime, 0,
227 					 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
228 					 AXG_FIFO_MIN_DEPTH);
229 	if (ret)
230 		return ret;
231 
232 	ret = request_irq(fifo->irq, axg_fifo_pcm_irq_block, 0,
233 			  dev_name(dev), ss);
234 	if (ret)
235 		return ret;
236 
237 	/* Enable pclk to access registers and clock the fifo ip */
238 	ret = clk_prepare_enable(fifo->pclk);
239 	if (ret)
240 		return ret;
241 
242 	/* Setup status2 so it reports the memory pointer */
243 	regmap_update_bits(fifo->map, FIFO_CTRL1,
244 			   CTRL1_STATUS2_SEL_MASK,
245 			   CTRL1_STATUS2_SEL(STATUS2_SEL_DDR_READ));
246 
247 	/* Make sure the dma is initially disabled */
248 	__dma_enable(fifo, false);
249 
250 	/* Disable irqs until params are ready */
251 	regmap_update_bits(fifo->map, FIFO_CTRL0,
252 			   CTRL0_INT_EN(FIFO_INT_MASK), 0);
253 
254 	/* Clear any pending interrupt */
255 	axg_fifo_ack_irq(fifo, FIFO_INT_MASK);
256 
257 	/* Take memory arbitror out of reset */
258 	ret = reset_control_deassert(fifo->arb);
259 	if (ret)
260 		clk_disable_unprepare(fifo->pclk);
261 
262 	return ret;
263 }
264 EXPORT_SYMBOL_GPL(axg_fifo_pcm_open);
265 
266 int axg_fifo_pcm_close(struct snd_soc_component *component,
267 		       struct snd_pcm_substream *ss)
268 {
269 	struct axg_fifo *fifo = axg_fifo_data(ss);
270 	int ret;
271 
272 	/* Put the memory arbitror back in reset */
273 	ret = reset_control_assert(fifo->arb);
274 
275 	/* Disable fifo ip and register access */
276 	clk_disable_unprepare(fifo->pclk);
277 
278 	/* remove IRQ */
279 	free_irq(fifo->irq, ss);
280 
281 	return ret;
282 }
283 EXPORT_SYMBOL_GPL(axg_fifo_pcm_close);
284 
285 int axg_fifo_pcm_new(struct snd_soc_pcm_runtime *rtd, unsigned int type)
286 {
287 	struct snd_card *card = rtd->card->snd_card;
288 	size_t size = axg_fifo_hw.buffer_bytes_max;
289 
290 	snd_pcm_lib_preallocate_pages(rtd->pcm->streams[type].substream,
291 				      SNDRV_DMA_TYPE_DEV, card->dev,
292 				      size, size);
293 	return 0;
294 }
295 EXPORT_SYMBOL_GPL(axg_fifo_pcm_new);
296 
297 static const struct regmap_config axg_fifo_regmap_cfg = {
298 	.reg_bits	= 32,
299 	.val_bits	= 32,
300 	.reg_stride	= 4,
301 	.max_register	= FIFO_CTRL2,
302 };
303 
304 int axg_fifo_probe(struct platform_device *pdev)
305 {
306 	struct device *dev = &pdev->dev;
307 	const struct axg_fifo_match_data *data;
308 	struct axg_fifo *fifo;
309 	void __iomem *regs;
310 
311 	data = of_device_get_match_data(dev);
312 	if (!data) {
313 		dev_err(dev, "failed to match device\n");
314 		return -ENODEV;
315 	}
316 
317 	fifo = devm_kzalloc(dev, sizeof(*fifo), GFP_KERNEL);
318 	if (!fifo)
319 		return -ENOMEM;
320 	platform_set_drvdata(pdev, fifo);
321 
322 	regs = devm_platform_ioremap_resource(pdev, 0);
323 	if (IS_ERR(regs))
324 		return PTR_ERR(regs);
325 
326 	fifo->map = devm_regmap_init_mmio(dev, regs, &axg_fifo_regmap_cfg);
327 	if (IS_ERR(fifo->map)) {
328 		dev_err(dev, "failed to init regmap: %ld\n",
329 			PTR_ERR(fifo->map));
330 		return PTR_ERR(fifo->map);
331 	}
332 
333 	fifo->pclk = devm_clk_get(dev, NULL);
334 	if (IS_ERR(fifo->pclk)) {
335 		if (PTR_ERR(fifo->pclk) != -EPROBE_DEFER)
336 			dev_err(dev, "failed to get pclk: %ld\n",
337 				PTR_ERR(fifo->pclk));
338 		return PTR_ERR(fifo->pclk);
339 	}
340 
341 	fifo->arb = devm_reset_control_get_exclusive(dev, NULL);
342 	if (IS_ERR(fifo->arb)) {
343 		if (PTR_ERR(fifo->arb) != -EPROBE_DEFER)
344 			dev_err(dev, "failed to get arb reset: %ld\n",
345 				PTR_ERR(fifo->arb));
346 		return PTR_ERR(fifo->arb);
347 	}
348 
349 	fifo->irq = of_irq_get(dev->of_node, 0);
350 	if (fifo->irq <= 0) {
351 		dev_err(dev, "failed to get irq: %d\n", fifo->irq);
352 		return fifo->irq;
353 	}
354 
355 	return devm_snd_soc_register_component(dev, data->component_drv,
356 					       data->dai_drv, 1);
357 }
358 EXPORT_SYMBOL_GPL(axg_fifo_probe);
359 
360 MODULE_DESCRIPTION("Amlogic AXG/G12A fifo driver");
361 MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
362 MODULE_LICENSE("GPL v2");
363