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
20 static 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
26 static 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
41 static 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
76 static void
77 kirkwood_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
101 static 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
156 static 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
177 static 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
197 static 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
223 static 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
240 static 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
257 const 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 };
266
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