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
kirkwood_priv(struct snd_pcm_substream * subs)20 static 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(asoc_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
kirkwood_dma_irq(int irq,void * dev_id)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
kirkwood_dma_conf_mbus_windows(void __iomem * base,int win,unsigned long dma,const struct mbus_dram_target_info * dram)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
kirkwood_dma_open(struct snd_soc_component * component,struct snd_pcm_substream * substream)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 const struct mbus_dram_target_info *dram;
108 unsigned long addr;
109
110 snd_soc_set_runtime_hwparams(substream, &kirkwood_dma_snd_hw);
111
112 /* Ensure that all constraints linked to dma burst are fulfilled */
113 err = snd_pcm_hw_constraint_minmax(runtime,
114 SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
115 priv->burst * 2,
116 KIRKWOOD_AUDIO_BUF_MAX-1);
117 if (err < 0)
118 return err;
119
120 err = snd_pcm_hw_constraint_step(runtime, 0,
121 SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
122 priv->burst);
123 if (err < 0)
124 return err;
125
126 err = snd_pcm_hw_constraint_step(substream->runtime, 0,
127 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
128 priv->burst);
129 if (err < 0)
130 return err;
131
132 if (!priv->substream_play && !priv->substream_rec) {
133 err = request_irq(priv->irq, kirkwood_dma_irq, IRQF_SHARED,
134 "kirkwood-i2s", priv);
135 if (err)
136 return err;
137
138 /*
139 * Enable Error interrupts. We're only ack'ing them but
140 * it's useful for diagnostics
141 */
142 writel((unsigned int)-1, priv->io + KIRKWOOD_ERR_MASK);
143 }
144
145 dram = mv_mbus_dram_info();
146 addr = substream->dma_buffer.addr;
147 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
148 if (priv->substream_play)
149 return -EBUSY;
150 priv->substream_play = substream;
151 kirkwood_dma_conf_mbus_windows(priv->io,
152 KIRKWOOD_PLAYBACK_WIN, addr, dram);
153 } else {
154 if (priv->substream_rec)
155 return -EBUSY;
156 priv->substream_rec = substream;
157 kirkwood_dma_conf_mbus_windows(priv->io,
158 KIRKWOOD_RECORD_WIN, addr, dram);
159 }
160
161 return 0;
162 }
163
kirkwood_dma_close(struct snd_soc_component * component,struct snd_pcm_substream * substream)164 static int kirkwood_dma_close(struct snd_soc_component *component,
165 struct snd_pcm_substream *substream)
166 {
167 struct kirkwood_dma_data *priv = kirkwood_priv(substream);
168
169 if (!priv)
170 return 0;
171
172 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
173 priv->substream_play = NULL;
174 else
175 priv->substream_rec = NULL;
176
177 if (!priv->substream_play && !priv->substream_rec) {
178 writel(0, priv->io + KIRKWOOD_ERR_MASK);
179 free_irq(priv->irq, priv);
180 }
181
182 return 0;
183 }
184
kirkwood_dma_prepare(struct snd_soc_component * component,struct snd_pcm_substream * substream)185 static int kirkwood_dma_prepare(struct snd_soc_component *component,
186 struct snd_pcm_substream *substream)
187 {
188 struct snd_pcm_runtime *runtime = substream->runtime;
189 struct kirkwood_dma_data *priv = kirkwood_priv(substream);
190 unsigned long size, count;
191
192 /* compute buffer size in term of "words" as requested in specs */
193 size = frames_to_bytes(runtime, runtime->buffer_size);
194 size = (size>>2)-1;
195 count = snd_pcm_lib_period_bytes(substream);
196
197 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
198 writel(count, priv->io + KIRKWOOD_PLAY_BYTE_INT_COUNT);
199 writel(runtime->dma_addr, priv->io + KIRKWOOD_PLAY_BUF_ADDR);
200 writel(size, priv->io + KIRKWOOD_PLAY_BUF_SIZE);
201 } else {
202 writel(count, priv->io + KIRKWOOD_REC_BYTE_INT_COUNT);
203 writel(runtime->dma_addr, priv->io + KIRKWOOD_REC_BUF_ADDR);
204 writel(size, priv->io + KIRKWOOD_REC_BUF_SIZE);
205 }
206
207
208 return 0;
209 }
210
kirkwood_dma_pointer(struct snd_soc_component * component,struct snd_pcm_substream * substream)211 static snd_pcm_uframes_t kirkwood_dma_pointer(
212 struct snd_soc_component *component,
213 struct snd_pcm_substream *substream)
214 {
215 struct kirkwood_dma_data *priv = kirkwood_priv(substream);
216 snd_pcm_uframes_t count;
217
218 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
219 count = bytes_to_frames(substream->runtime,
220 readl(priv->io + KIRKWOOD_PLAY_BYTE_COUNT));
221 else
222 count = bytes_to_frames(substream->runtime,
223 readl(priv->io + KIRKWOOD_REC_BYTE_COUNT));
224
225 return count;
226 }
227
kirkwood_dma_new(struct snd_soc_component * component,struct snd_soc_pcm_runtime * rtd)228 static int kirkwood_dma_new(struct snd_soc_component *component,
229 struct snd_soc_pcm_runtime *rtd)
230 {
231 size_t size = kirkwood_dma_snd_hw.buffer_bytes_max;
232 struct snd_card *card = rtd->card->snd_card;
233 int ret;
234
235 ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
236 if (ret)
237 return ret;
238
239 snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
240 card->dev, size, size);
241
242 return 0;
243 }
244
245 const struct snd_soc_component_driver kirkwood_soc_component = {
246 .name = DRV_NAME,
247 .open = kirkwood_dma_open,
248 .close = kirkwood_dma_close,
249 .prepare = kirkwood_dma_prepare,
250 .pointer = kirkwood_dma_pointer,
251 .pcm_construct = kirkwood_dma_new,
252 };
253