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Source at commit 1c406da created 12 years 7 months ago. By Xiangfu Liu, ben nanonote: forward patches to linux-3.0 | |
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1 | From 5e689acca07bccdced123f82e8dde5459eca0d97 Mon Sep 17 00:00:00 2001 |
2 | From: Xiangfu Liu <xiangfu@macbook.openmobilefree.net> |
3 | Date: Wed, 14 Sep 2011 14:30:01 +0800 |
4 | Subject: [PATCH 26/29] sound: update DMA code |
5 | |
6 | --- |
7 | sound/soc/jz4740/jz4740-pcm.c | 21 ++++++++++++++++++--- |
8 | 1 files changed, 18 insertions(+), 3 deletions(-) |
9 | |
10 | diff --git a/sound/soc/jz4740/jz4740-pcm.c b/sound/soc/jz4740/jz4740-pcm.c |
11 | index fb1483f..71c455d 100644 |
12 | --- a/sound/soc/jz4740/jz4740-pcm.c |
13 | +++ b/sound/soc/jz4740/jz4740-pcm.c |
14 | @@ -31,6 +31,7 @@ |
15 | |
16 | struct jz4740_runtime_data { |
17 | unsigned long dma_period; |
18 | + unsigned long dma_period_left; |
19 | dma_addr_t dma_start; |
20 | dma_addr_t dma_pos; |
21 | dma_addr_t dma_end; |
22 | @@ -67,10 +68,13 @@ static void jz4740_pcm_start_transfer(struct jz4740_runtime_data *prtd, |
23 | if (prtd->dma_pos == prtd->dma_end) |
24 | prtd->dma_pos = prtd->dma_start; |
25 | |
26 | - if (prtd->dma_pos + prtd->dma_period > prtd->dma_end) |
27 | + if (prtd->dma_period_left == 0) |
28 | + prtd->dma_period_left = prtd->dma_period; |
29 | + |
30 | + if (prtd->dma_pos + prtd->dma_period_left > prtd->dma_end) |
31 | count = prtd->dma_end - prtd->dma_pos; |
32 | else |
33 | - count = prtd->dma_period; |
34 | + count = prtd->dma_period_left; |
35 | |
36 | jz4740_dma_disable(prtd->dma); |
37 | |
38 | @@ -85,6 +89,7 @@ static void jz4740_pcm_start_transfer(struct jz4740_runtime_data *prtd, |
39 | jz4740_dma_set_transfer_count(prtd->dma, count); |
40 | |
41 | prtd->dma_pos += count; |
42 | + prtd->dma_period_left -= count; |
43 | |
44 | jz4740_dma_enable(prtd->dma); |
45 | } |
46 | @@ -96,7 +101,8 @@ static void jz4740_pcm_dma_transfer_done(struct jz4740_dma_chan *dma, int err, |
47 | struct snd_pcm_runtime *runtime = substream->runtime; |
48 | struct jz4740_runtime_data *prtd = runtime->private_data; |
49 | |
50 | - snd_pcm_period_elapsed(substream); |
51 | + if (prtd->dma_period_left == 0) |
52 | + snd_pcm_period_elapsed(substream); |
53 | |
54 | jz4740_pcm_start_transfer(prtd, substream); |
55 | } |
56 | @@ -133,6 +139,7 @@ static int jz4740_pcm_hw_params(struct snd_pcm_substream *substream, |
57 | runtime->dma_bytes = params_buffer_bytes(params); |
58 | |
59 | prtd->dma_period = params_period_bytes(params); |
60 | + prtd->dma_period_left = 0; |
61 | prtd->dma_start = runtime->dma_addr; |
62 | prtd->dma_pos = prtd->dma_start; |
63 | prtd->dma_end = prtd->dma_start + runtime->dma_bytes; |
64 | @@ -160,6 +167,7 @@ static int jz4740_pcm_prepare(struct snd_pcm_substream *substream) |
65 | if (!prtd->dma) |
66 | return -EBUSY; |
67 | |
68 | + prtd->dma_period_left = 0; |
69 | prtd->dma_pos = prtd->dma_start; |
70 | |
71 | return 0; |
72 | @@ -219,6 +227,13 @@ static int jz4740_pcm_open(struct snd_pcm_substream *substream) |
73 | if (prtd == NULL) |
74 | return -ENOMEM; |
75 | |
76 | + /* Force period and buffer size to be a multiple of the DMA transfer |
77 | + * size, which is 16 bytes. */ |
78 | + snd_pcm_hw_constraint_step(runtime, 0, |
79 | + SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 16); |
80 | + snd_pcm_hw_constraint_step(runtime, 0, |
81 | + SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 16); |
82 | + |
83 | snd_soc_set_runtime_hwparams(substream, &jz4740_pcm_hardware); |
84 | |
85 | runtime->private_data = prtd; |
86 | -- |
87 | 1.7.4.1 |
88 | |
89 |