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 = subs->private_data;
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(addr: priv->io + KIRKWOOD_INT_MASK);
47 status = readl(addr: priv->io + KIRKWOOD_INT_CAUSE) & mask;
48
49 cause = readl(addr: 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(val: cause, addr: 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(val: status, addr: priv->io + KIRKWOOD_INT_CAUSE);
66
67 if (status & KIRKWOOD_INT_CAUSE_PLAY_BYTES)
68 snd_pcm_period_elapsed(substream: priv->substream_play);
69
70 if (status & KIRKWOOD_INT_CAUSE_REC_BYTES)
71 snd_pcm_period_elapsed(substream: 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(val: 0, addr: base + KIRKWOOD_AUDIO_WIN_CTRL_REG(win));
85 writel(val: 0, addr: 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(val: cs->base & 0xffff0000,
92 addr: base + KIRKWOOD_AUDIO_WIN_BASE_REG(win));
93 writel(val: ((cs->size - 1) & 0xffff0000) |
94 (cs->mbus_attr << 8) |
95 (dram->mbus_dram_target_id << 4) | 1,
96 addr: 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(subs: substream);
107
108 snd_soc_set_runtime_hwparams(substream, hw: &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 min: 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, cond: 0,
119 SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
120 step: priv->burst);
121 if (err < 0)
122 return err;
123
124 err = snd_pcm_hw_constraint_step(runtime: substream->runtime, cond: 0,
125 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
126 step: priv->burst);
127 if (err < 0)
128 return err;
129
130 if (!priv->substream_play && !priv->substream_rec) {
131 err = request_irq(irq: priv->irq, handler: kirkwood_dma_irq, IRQF_SHARED,
132 name: "kirkwood-i2s", dev: 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(val: (unsigned int)-1, addr: 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(subs: 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(val: 0, addr: 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(subs: substream);
182 const struct mbus_dram_target_info *dram = mv_mbus_dram_info();
183 unsigned long addr = substream->runtime->dma_addr;
184
185 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
186 kirkwood_dma_conf_mbus_windows(base: priv->io,
187 KIRKWOOD_PLAYBACK_WIN, dma: addr, dram);
188 else
189 kirkwood_dma_conf_mbus_windows(base: priv->io,
190 KIRKWOOD_RECORD_WIN, dma: addr, dram);
191 return 0;
192}
193
194static int kirkwood_dma_prepare(struct snd_soc_component *component,
195 struct snd_pcm_substream *substream)
196{
197 struct snd_pcm_runtime *runtime = substream->runtime;
198 struct kirkwood_dma_data *priv = kirkwood_priv(subs: substream);
199 unsigned long size, count;
200
201 /* compute buffer size in term of "words" as requested in specs */
202 size = frames_to_bytes(runtime, size: runtime->buffer_size);
203 size = (size>>2)-1;
204 count = snd_pcm_lib_period_bytes(substream);
205
206 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
207 writel(val: count, addr: priv->io + KIRKWOOD_PLAY_BYTE_INT_COUNT);
208 writel(val: runtime->dma_addr, addr: priv->io + KIRKWOOD_PLAY_BUF_ADDR);
209 writel(val: size, addr: priv->io + KIRKWOOD_PLAY_BUF_SIZE);
210 } else {
211 writel(val: count, addr: priv->io + KIRKWOOD_REC_BYTE_INT_COUNT);
212 writel(val: runtime->dma_addr, addr: priv->io + KIRKWOOD_REC_BUF_ADDR);
213 writel(val: size, addr: priv->io + KIRKWOOD_REC_BUF_SIZE);
214 }
215
216
217 return 0;
218}
219
220static snd_pcm_uframes_t kirkwood_dma_pointer(
221 struct snd_soc_component *component,
222 struct snd_pcm_substream *substream)
223{
224 struct kirkwood_dma_data *priv = kirkwood_priv(subs: substream);
225 snd_pcm_uframes_t count;
226
227 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
228 count = bytes_to_frames(runtime: substream->runtime,
229 readl(addr: priv->io + KIRKWOOD_PLAY_BYTE_COUNT));
230 else
231 count = bytes_to_frames(runtime: substream->runtime,
232 readl(addr: priv->io + KIRKWOOD_REC_BYTE_COUNT));
233
234 return count;
235}
236
237static int kirkwood_dma_new(struct snd_soc_component *component,
238 struct snd_soc_pcm_runtime *rtd)
239{
240 size_t size = kirkwood_dma_snd_hw.buffer_bytes_max;
241 struct snd_card *card = rtd->card->snd_card;
242 int ret;
243
244 ret = dma_coerce_mask_and_coherent(dev: card->dev, DMA_BIT_MASK(32));
245 if (ret)
246 return ret;
247
248 snd_pcm_set_managed_buffer_all(pcm: rtd->pcm, SNDRV_DMA_TYPE_DEV,
249 data: card->dev, size, max: size);
250
251 return 0;
252}
253
254const struct snd_soc_component_driver kirkwood_soc_component = {
255 .name = DRV_NAME,
256 .open = kirkwood_dma_open,
257 .close = kirkwood_dma_close,
258 .hw_params = kirkwood_dma_hw_params,
259 .prepare = kirkwood_dma_prepare,
260 .pointer = kirkwood_dma_pointer,
261 .pcm_construct = kirkwood_dma_new,
262};
263

source code of linux/sound/soc/kirkwood/kirkwood-dma.c