kirkwood-dma.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * kirkwood-dma.c
  4 *
  5 * (c) 2010 Arnaud Patard <apatard@mandriva.com>
  6 * (c) 2010 Arnaud Patard <arnaud.patard@rtp-net.org>
  7 */
  8
  9#include <linux/init.h>
 10#include <linux/module.h>
 11#include <linux/device.h>
 12#include <linux/io.h>
 13#include <linux/slab.h>
 14#include <linux/interrupt.h>
 15#include <linux/dma-mapping.h>
 16#include <linux/mbus.h>
 17#include <sound/soc.h>
 18#include "kirkwood.h"
 19
 20static struct kirkwood_dma_data *kirkwood_priv(struct snd_pcm_substream *subs)
 21{
 22	struct snd_soc_pcm_runtime *soc_runtime = snd_soc_substream_to_rtd(subs);
 23	return snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(soc_runtime, 0));
 24}
 25
 26static const struct snd_pcm_hardware kirkwood_dma_snd_hw = {
 27	.info = SNDRV_PCM_INFO_INTERLEAVED |
 28		SNDRV_PCM_INFO_MMAP |
 29		SNDRV_PCM_INFO_MMAP_VALID |
 30		SNDRV_PCM_INFO_BLOCK_TRANSFER |
 31		SNDRV_PCM_INFO_PAUSE |
 32		SNDRV_PCM_INFO_NO_PERIOD_WAKEUP,
 33	.buffer_bytes_max	= KIRKWOOD_SND_MAX_BUFFER_BYTES,
 34	.period_bytes_min	= KIRKWOOD_SND_MIN_PERIOD_BYTES,
 35	.period_bytes_max	= KIRKWOOD_SND_MAX_PERIOD_BYTES,
 36	.periods_min		= KIRKWOOD_SND_MIN_PERIODS,
 37	.periods_max		= KIRKWOOD_SND_MAX_PERIODS,
 38	.fifo_size		= 0,
 39};
 40
 41static irqreturn_t kirkwood_dma_irq(int irq, void *dev_id)
 42{
 43	struct kirkwood_dma_data *priv = dev_id;
 44	unsigned long mask, status, cause;
 45
 46	mask = readl(priv->io + KIRKWOOD_INT_MASK);
 47	status = readl(priv->io + KIRKWOOD_INT_CAUSE) & mask;
 48
 49	cause = readl(priv->io + KIRKWOOD_ERR_CAUSE);
 50	if (unlikely(cause)) {
 51		printk(KERN_WARNING "%s: got err interrupt 0x%lx\n",
 52				__func__, cause);
 53		writel(cause, priv->io + KIRKWOOD_ERR_CAUSE);
 54	}
 55
 56	/* we've enabled only bytes interrupts ... */
 57	if (status & ~(KIRKWOOD_INT_CAUSE_PLAY_BYTES | \
 58			KIRKWOOD_INT_CAUSE_REC_BYTES)) {
 59		printk(KERN_WARNING "%s: unexpected interrupt %lx\n",
 60			__func__, status);
 61		return IRQ_NONE;
 62	}
 63
 64	/* ack int */
 65	writel(status, priv->io + KIRKWOOD_INT_CAUSE);
 66
 67	if (status & KIRKWOOD_INT_CAUSE_PLAY_BYTES)
 68		snd_pcm_period_elapsed(priv->substream_play);
 69
 70	if (status & KIRKWOOD_INT_CAUSE_REC_BYTES)
 71		snd_pcm_period_elapsed(priv->substream_rec);
 72
 73	return IRQ_HANDLED;
 74}
 75
 76static void
 77kirkwood_dma_conf_mbus_windows(void __iomem *base, int win,
 78			       unsigned long dma,
 79			       const struct mbus_dram_target_info *dram)
 80{
 81	int i;
 82
 83	/* First disable and clear windows */
 84	writel(0, base + KIRKWOOD_AUDIO_WIN_CTRL_REG(win));
 85	writel(0, base + KIRKWOOD_AUDIO_WIN_BASE_REG(win));
 86
 87	/* try to find matching cs for current dma address */
 88	for (i = 0; i < dram->num_cs; i++) {
 89		const struct mbus_dram_window *cs = &dram->cs[i];
 90		if ((cs->base & 0xffff0000) < (dma & 0xffff0000)) {
 91			writel(cs->base & 0xffff0000,
 92				base + KIRKWOOD_AUDIO_WIN_BASE_REG(win));
 93			writel(((cs->size - 1) & 0xffff0000) |
 94				(cs->mbus_attr << 8) |
 95				(dram->mbus_dram_target_id << 4) | 1,
 96				base + KIRKWOOD_AUDIO_WIN_CTRL_REG(win));
 97		}
 98	}
 99}
100
101static int kirkwood_dma_open(struct snd_soc_component *component,
102			     struct snd_pcm_substream *substream)
103{
104	int err;
105	struct snd_pcm_runtime *runtime = substream->runtime;
106	struct kirkwood_dma_data *priv = kirkwood_priv(substream);
107
108	snd_soc_set_runtime_hwparams(substream, &kirkwood_dma_snd_hw);
109
110	/* Ensure that all constraints linked to dma burst are fulfilled */
111	err = snd_pcm_hw_constraint_minmax(runtime,
112			SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
113			priv->burst * 2,
114			KIRKWOOD_AUDIO_BUF_MAX-1);
115	if (err < 0)
116		return err;
117
118	err = snd_pcm_hw_constraint_step(runtime, 0,
119			SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
120			priv->burst);
121	if (err < 0)
122		return err;
123
124	err = snd_pcm_hw_constraint_step(substream->runtime, 0,
125			 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
126			 priv->burst);
127	if (err < 0)
128		return err;
129
130	if (!priv->substream_play && !priv->substream_rec) {
131		err = request_irq(priv->irq, kirkwood_dma_irq, IRQF_SHARED,
132				  "kirkwood-i2s", priv);
133		if (err)
134			return err;
135
136		/*
137		 * Enable Error interrupts. We're only ack'ing them but
138		 * it's useful for diagnostics
139		 */
140		writel((unsigned int)-1, priv->io + KIRKWOOD_ERR_MASK);
141	}
142
143	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
144		if (priv->substream_play)
145			return -EBUSY;
146		priv->substream_play = substream;
147	} else {
148		if (priv->substream_rec)
149			return -EBUSY;
150		priv->substream_rec = substream;
151	}
152
153	return 0;
154}
155
156static int kirkwood_dma_close(struct snd_soc_component *component,
157			      struct snd_pcm_substream *substream)
158{
159	struct kirkwood_dma_data *priv = kirkwood_priv(substream);
160
161	if (!priv)
162		return 0;
163
164	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
165		priv->substream_play = NULL;
166	else
167		priv->substream_rec = NULL;
168
169	if (!priv->substream_play && !priv->substream_rec) {
170		writel(0, priv->io + KIRKWOOD_ERR_MASK);
171		free_irq(priv->irq, priv);
172	}
173
174	return 0;
175}
176
177static int kirkwood_dma_hw_params(struct snd_soc_component *component,
178				  struct snd_pcm_substream *substream,
179				  struct snd_pcm_hw_params *params)
180{
181	struct kirkwood_dma_data *priv = kirkwood_priv(substream);
182	const struct mbus_dram_target_info *dram = mv_mbus_dram_info();
183	unsigned long addr = substream->runtime->dma_addr;
184
185	if (!dram)
186		return 0;
187
188	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
189		kirkwood_dma_conf_mbus_windows(priv->io,
190			KIRKWOOD_PLAYBACK_WIN, addr, dram);
191	else
192		kirkwood_dma_conf_mbus_windows(priv->io,
193			KIRKWOOD_RECORD_WIN, addr, dram);
194	return 0;
195}
196
197static int kirkwood_dma_prepare(struct snd_soc_component *component,
198				struct snd_pcm_substream *substream)
199{
200	struct snd_pcm_runtime *runtime = substream->runtime;
201	struct kirkwood_dma_data *priv = kirkwood_priv(substream);
202	unsigned long size, count;
203
204	/* compute buffer size in term of "words" as requested in specs */
205	size = frames_to_bytes(runtime, runtime->buffer_size);
206	size = (size>>2)-1;
207	count = snd_pcm_lib_period_bytes(substream);
208
209	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
210		writel(count, priv->io + KIRKWOOD_PLAY_BYTE_INT_COUNT);
211		writel(runtime->dma_addr, priv->io + KIRKWOOD_PLAY_BUF_ADDR);
212		writel(size, priv->io + KIRKWOOD_PLAY_BUF_SIZE);
213	} else {
214		writel(count, priv->io + KIRKWOOD_REC_BYTE_INT_COUNT);
215		writel(runtime->dma_addr, priv->io + KIRKWOOD_REC_BUF_ADDR);
216		writel(size, priv->io + KIRKWOOD_REC_BUF_SIZE);
217	}
218
219
220	return 0;
221}
222
223static snd_pcm_uframes_t kirkwood_dma_pointer(
224	struct snd_soc_component *component,
225	struct snd_pcm_substream *substream)
226{
227	struct kirkwood_dma_data *priv = kirkwood_priv(substream);
228	snd_pcm_uframes_t count;
229
230	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
231		count = bytes_to_frames(substream->runtime,
232			readl(priv->io + KIRKWOOD_PLAY_BYTE_COUNT));
233	else
234		count = bytes_to_frames(substream->runtime,
235			readl(priv->io + KIRKWOOD_REC_BYTE_COUNT));
236
237	return count;
238}
239
240static int kirkwood_dma_new(struct snd_soc_component *component,
241			    struct snd_soc_pcm_runtime *rtd)
242{
243	size_t size = kirkwood_dma_snd_hw.buffer_bytes_max;
244	struct snd_card *card = rtd->card->snd_card;
245	int ret;
246
247	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
248	if (ret)
249		return ret;
250
251	snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
252				       card->dev, size, size);
253
254	return 0;
255}
256
257const struct snd_soc_component_driver kirkwood_soc_component = {
258	.name		= DRV_NAME,
259	.open		= kirkwood_dma_open,
260	.close		= kirkwood_dma_close,
261	.hw_params	= kirkwood_dma_hw_params,
262	.prepare	= kirkwood_dma_prepare,
263	.pointer	= kirkwood_dma_pointer,
264	.pcm_construct	= kirkwood_dma_new,
265};