xref: /openbmc/linux/sound/soc/samsung/idma.c (revision a93fbb00) 
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // idma.c - I2S0 internal DMA driver
4 //
5 // Copyright (c) 2011 Samsung Electronics Co., Ltd.
6 //		http://www.samsung.com
7 
8 #include <linux/interrupt.h>
9 #include <linux/platform_device.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/slab.h>
12 #include <linux/module.h>
13 #include <sound/pcm.h>
14 #include <sound/pcm_params.h>
15 #include <sound/soc.h>
16 
17 #include "i2s.h"
18 #include "idma.h"
19 #include "i2s-regs.h"
20 
21 #define ST_RUNNING		(1<<0)
22 #define ST_OPENED		(1<<1)
23 
24 static const struct snd_pcm_hardware idma_hardware = {
25 	.info = SNDRV_PCM_INFO_INTERLEAVED |
26 		    SNDRV_PCM_INFO_BLOCK_TRANSFER |
27 		    SNDRV_PCM_INFO_MMAP |
28 		    SNDRV_PCM_INFO_MMAP_VALID |
29 		    SNDRV_PCM_INFO_PAUSE |
30 		    SNDRV_PCM_INFO_RESUME,
31 	.buffer_bytes_max = MAX_IDMA_BUFFER,
32 	.period_bytes_min = 128,
33 	.period_bytes_max = MAX_IDMA_PERIOD,
34 	.periods_min = 1,
35 	.periods_max = 2,
36 };
37 
38 struct idma_ctrl {
39 	spinlock_t	lock;
40 	int		state;
41 	dma_addr_t	start;
42 	dma_addr_t	pos;
43 	dma_addr_t	end;
44 	dma_addr_t	period;
45 	dma_addr_t	periodsz;
46 	void		*token;
47 	void		(*cb)(void *dt, int bytes_xfer);
48 };
49 
50 static struct idma_info {
51 	spinlock_t	lock;
52 	void		 __iomem  *regs;
53 	dma_addr_t	lp_tx_addr;
54 } idma;
55 
56 static int idma_irq;
57 
58 static void idma_getpos(dma_addr_t *src)
59 {
60 	*src = idma.lp_tx_addr +
61 		(readl(idma.regs + I2STRNCNT) & 0xffffff) * 4;
62 }
63 
64 static int idma_enqueue(struct snd_pcm_substream *substream)
65 {
66 	struct snd_pcm_runtime *runtime = substream->runtime;
67 	struct idma_ctrl *prtd = substream->runtime->private_data;
68 	u32 val;
69 
70 	spin_lock(&prtd->lock);
71 	prtd->token = (void *) substream;
72 	spin_unlock(&prtd->lock);
73 
74 	/* Internal DMA Level0 Interrupt Address */
75 	val = idma.lp_tx_addr + prtd->periodsz;
76 	writel(val, idma.regs + I2SLVL0ADDR);
77 
78 	/* Start address0 of I2S internal DMA operation. */
79 	val = idma.lp_tx_addr;
80 	writel(val, idma.regs + I2SSTR0);
81 
82 	/*
83 	 * Transfer block size for I2S internal DMA.
84 	 * Should decide transfer size before start dma operation
85 	 */
86 	val = readl(idma.regs + I2SSIZE);
87 	val &= ~(I2SSIZE_TRNMSK << I2SSIZE_SHIFT);
88 	val |= (((runtime->dma_bytes >> 2) &
89 			I2SSIZE_TRNMSK) << I2SSIZE_SHIFT);
90 	writel(val, idma.regs + I2SSIZE);
91 
92 	val = readl(idma.regs + I2SAHB);
93 	val |= AHB_INTENLVL0;
94 	writel(val, idma.regs + I2SAHB);
95 
96 	return 0;
97 }
98 
99 static void idma_setcallbk(struct snd_pcm_substream *substream,
100 				void (*cb)(void *, int))
101 {
102 	struct idma_ctrl *prtd = substream->runtime->private_data;
103 
104 	spin_lock(&prtd->lock);
105 	prtd->cb = cb;
106 	spin_unlock(&prtd->lock);
107 }
108 
109 static void idma_control(int op)
110 {
111 	u32 val = readl(idma.regs + I2SAHB);
112 
113 	spin_lock(&idma.lock);
114 
115 	switch (op) {
116 	case LPAM_DMA_START:
117 		val |= (AHB_INTENLVL0 | AHB_DMAEN);
118 		break;
119 	case LPAM_DMA_STOP:
120 		val &= ~(AHB_INTENLVL0 | AHB_DMAEN);
121 		break;
122 	default:
123 		spin_unlock(&idma.lock);
124 		return;
125 	}
126 
127 	writel(val, idma.regs + I2SAHB);
128 	spin_unlock(&idma.lock);
129 }
130 
131 static void idma_done(void *id, int bytes_xfer)
132 {
133 	struct snd_pcm_substream *substream = id;
134 	struct idma_ctrl *prtd = substream->runtime->private_data;
135 
136 	if (prtd && (prtd->state & ST_RUNNING))
137 		snd_pcm_period_elapsed(substream);
138 }
139 
140 static int idma_hw_params(struct snd_soc_component *component,
141 			  struct snd_pcm_substream *substream,
142 			  struct snd_pcm_hw_params *params)
143 {
144 	struct snd_pcm_runtime *runtime = substream->runtime;
145 	struct idma_ctrl *prtd = substream->runtime->private_data;
146 	u32 mod = readl(idma.regs + I2SMOD);
147 	u32 ahb = readl(idma.regs + I2SAHB);
148 
149 	ahb |= (AHB_DMARLD | AHB_INTMASK);
150 	mod |= MOD_TXS_IDMA;
151 	writel(ahb, idma.regs + I2SAHB);
152 	writel(mod, idma.regs + I2SMOD);
153 
154 	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
155 	runtime->dma_bytes = params_buffer_bytes(params);
156 
157 	prtd->start = prtd->pos = runtime->dma_addr;
158 	prtd->period = params_periods(params);
159 	prtd->periodsz = params_period_bytes(params);
160 	prtd->end = runtime->dma_addr + runtime->dma_bytes;
161 
162 	idma_setcallbk(substream, idma_done);
163 
164 	return 0;
165 }
166 
167 static int idma_hw_free(struct snd_soc_component *component,
168 			struct snd_pcm_substream *substream)
169 {
170 	snd_pcm_set_runtime_buffer(substream, NULL);
171 
172 	return 0;
173 }
174 
175 static int idma_prepare(struct snd_soc_component *component,
176 			struct snd_pcm_substream *substream)
177 {
178 	struct idma_ctrl *prtd = substream->runtime->private_data;
179 
180 	prtd->pos = prtd->start;
181 
182 	/* flush the DMA channel */
183 	idma_control(LPAM_DMA_STOP);
184 	idma_enqueue(substream);
185 
186 	return 0;
187 }
188 
189 static int idma_trigger(struct snd_soc_component *component,
190 			struct snd_pcm_substream *substream, int cmd)
191 {
192 	struct idma_ctrl *prtd = substream->runtime->private_data;
193 	int ret = 0;
194 
195 	spin_lock(&prtd->lock);
196 
197 	switch (cmd) {
198 	case SNDRV_PCM_TRIGGER_RESUME:
199 	case SNDRV_PCM_TRIGGER_START:
200 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
201 		prtd->state |= ST_RUNNING;
202 		idma_control(LPAM_DMA_START);
203 		break;
204 
205 	case SNDRV_PCM_TRIGGER_SUSPEND:
206 	case SNDRV_PCM_TRIGGER_STOP:
207 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
208 		prtd->state &= ~ST_RUNNING;
209 		idma_control(LPAM_DMA_STOP);
210 		break;
211 
212 	default:
213 		ret = -EINVAL;
214 		break;
215 	}
216 
217 	spin_unlock(&prtd->lock);
218 
219 	return ret;
220 }
221 
222 static snd_pcm_uframes_t
223 idma_pointer(struct snd_soc_component *component,
224 	     struct snd_pcm_substream *substream)
225 {
226 	struct snd_pcm_runtime *runtime = substream->runtime;
227 	struct idma_ctrl *prtd = runtime->private_data;
228 	dma_addr_t src;
229 	unsigned long res;
230 
231 	spin_lock(&prtd->lock);
232 
233 	idma_getpos(&src);
234 	res = src - prtd->start;
235 
236 	spin_unlock(&prtd->lock);
237 
238 	return bytes_to_frames(substream->runtime, res);
239 }
240 
241 static int idma_mmap(struct snd_soc_component *component,
242 		     struct snd_pcm_substream *substream,
243 	struct vm_area_struct *vma)
244 {
245 	struct snd_pcm_runtime *runtime = substream->runtime;
246 	unsigned long size, offset;
247 
248 	/* From snd_pcm_lib_mmap_iomem */
249 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
250 	size = vma->vm_end - vma->vm_start;
251 	offset = vma->vm_pgoff << PAGE_SHIFT;
252 	return io_remap_pfn_range(vma, vma->vm_start,
253 			(runtime->dma_addr + offset) >> PAGE_SHIFT,
254 			size, vma->vm_page_prot);
255 }
256 
257 static irqreturn_t iis_irq(int irqno, void *dev_id)
258 {
259 	struct idma_ctrl *prtd = (struct idma_ctrl *)dev_id;
260 	u32 iisahb, val, addr;
261 
262 	iisahb  = readl(idma.regs + I2SAHB);
263 
264 	val = (iisahb & AHB_LVL0INT) ? AHB_CLRLVL0INT : 0;
265 
266 	if (val) {
267 		iisahb |= val;
268 		writel(iisahb, idma.regs + I2SAHB);
269 
270 		addr = readl(idma.regs + I2SLVL0ADDR) - idma.lp_tx_addr;
271 		addr += prtd->periodsz;
272 		addr %= (u32)(prtd->end - prtd->start);
273 		addr += idma.lp_tx_addr;
274 
275 		writel(addr, idma.regs + I2SLVL0ADDR);
276 
277 		if (prtd->cb)
278 			prtd->cb(prtd->token, prtd->period);
279 	}
280 
281 	return IRQ_HANDLED;
282 }
283 
284 static int idma_open(struct snd_soc_component *component,
285 		     struct snd_pcm_substream *substream)
286 {
287 	struct snd_pcm_runtime *runtime = substream->runtime;
288 	struct idma_ctrl *prtd;
289 	int ret;
290 
291 	snd_soc_set_runtime_hwparams(substream, &idma_hardware);
292 
293 	prtd = kzalloc(sizeof(struct idma_ctrl), GFP_KERNEL);
294 	if (prtd == NULL)
295 		return -ENOMEM;
296 
297 	ret = request_irq(idma_irq, iis_irq, 0, "i2s", prtd);
298 	if (ret < 0) {
299 		pr_err("fail to claim i2s irq , ret = %d\n", ret);
300 		kfree(prtd);
301 		return ret;
302 	}
303 
304 	spin_lock_init(&prtd->lock);
305 
306 	runtime->private_data = prtd;
307 
308 	return 0;
309 }
310 
311 static int idma_close(struct snd_soc_component *component,
312 		      struct snd_pcm_substream *substream)
313 {
314 	struct snd_pcm_runtime *runtime = substream->runtime;
315 	struct idma_ctrl *prtd = runtime->private_data;
316 
317 	free_irq(idma_irq, prtd);
318 
319 	if (!prtd)
320 		pr_err("idma_close called with prtd == NULL\n");
321 
322 	kfree(prtd);
323 
324 	return 0;
325 }
326 
327 static void idma_free(struct snd_soc_component *component,
328 		      struct snd_pcm *pcm)
329 {
330 	struct snd_pcm_substream *substream;
331 	struct snd_dma_buffer *buf;
332 
333 	substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
334 	if (!substream)
335 		return;
336 
337 	buf = &substream->dma_buffer;
338 	if (!buf->area)
339 		return;
340 
341 	iounmap((void __iomem *)buf->area);
342 
343 	buf->area = NULL;
344 	buf->addr = 0;
345 }
346 
347 static int preallocate_idma_buffer(struct snd_pcm *pcm, int stream)
348 {
349 	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
350 	struct snd_dma_buffer *buf = &substream->dma_buffer;
351 
352 	buf->dev.dev = pcm->card->dev;
353 	buf->private_data = NULL;
354 
355 	/* Assign PCM buffer pointers */
356 	buf->dev.type = SNDRV_DMA_TYPE_CONTINUOUS;
357 	buf->addr = idma.lp_tx_addr;
358 	buf->bytes = idma_hardware.buffer_bytes_max;
359 	buf->area = (unsigned char * __force)ioremap(buf->addr, buf->bytes);
360 	if (!buf->area)
361 		return -ENOMEM;
362 
363 	return 0;
364 }
365 
366 static int idma_new(struct snd_soc_component *component,
367 		    struct snd_soc_pcm_runtime *rtd)
368 {
369 	struct snd_card *card = rtd->card->snd_card;
370 	struct snd_pcm *pcm = rtd->pcm;
371 	int ret;
372 
373 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
374 	if (ret)
375 		return ret;
376 
377 	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
378 		ret = preallocate_idma_buffer(pcm,
379 				SNDRV_PCM_STREAM_PLAYBACK);
380 	}
381 
382 	return ret;
383 }
384 
385 void idma_reg_addr_init(void __iomem *regs, dma_addr_t addr)
386 {
387 	spin_lock_init(&idma.lock);
388 	idma.regs = regs;
389 	idma.lp_tx_addr = addr;
390 }
391 EXPORT_SYMBOL_GPL(idma_reg_addr_init);
392 
393 static const struct snd_soc_component_driver asoc_idma_platform = {
394 	.open		= idma_open,
395 	.close		= idma_close,
396 	.trigger	= idma_trigger,
397 	.pointer	= idma_pointer,
398 	.mmap		= idma_mmap,
399 	.hw_params	= idma_hw_params,
400 	.hw_free	= idma_hw_free,
401 	.prepare	= idma_prepare,
402 	.pcm_construct	= idma_new,
403 	.pcm_destruct	= idma_free,
404 };
405 
406 static int asoc_idma_platform_probe(struct platform_device *pdev)
407 {
408 	idma_irq = platform_get_irq(pdev, 0);
409 	if (idma_irq < 0)
410 		return idma_irq;
411 
412 	return devm_snd_soc_register_component(&pdev->dev, &asoc_idma_platform,
413 					       NULL, 0);
414 }
415 
416 static struct platform_driver asoc_idma_driver = {
417 	.driver = {
418 		.name = "samsung-idma",
419 	},
420 
421 	.probe = asoc_idma_platform_probe,
422 };
423 
424 module_platform_driver(asoc_idma_driver);
425 
426 MODULE_AUTHOR("Jaswinder Singh, <jassisinghbrar@gmail.com>");
427 MODULE_DESCRIPTION("Samsung ASoC IDMA Driver");
428 MODULE_LICENSE("GPL");
429