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192.168.1.100 / T108 / c2023d5d03be91dbb983606f0ec5e9e4ea36c8c2 / . / target / linux / layerscape / patches-5.4 / 801-audio-0028-MLK-15927-1-ASoC-fsl_sai-Fix-noise-when-using-EDMA.patch
blob: d3ab26b7c799d9b98ac15e6a8456b1547ac0bb3f [file] [log] [blame]
b.liue9582032025-04-17 19:18:16 +0800[diff] [blame]1From 3b671c297cff1ba5f5c3e089ffa82523eca3c598 Mon Sep 17 00:00:00 2001
2From: Mihai Serban <mihai.serban@nxp.com>
3Date: Fri, 7 Jul 2017 15:09:51 +0300
4Subject: [PATCH] MLK-15927-1: ASoC: fsl_sai: Fix noise when using EDMA
5
6EDMA requires the period size to be multiple of maxburst. Otherwise the
7remaining bytes are not transferred and thus noise is produced.
8
9We can handle this issue by adding a constraint on
10SNDRV_PCM_HW_PARAM_PERIOD_SIZE to be multiple of tx/rx maxburst value.
11
12This is based on a similar patch we have for ESAI:
13commit bd3f3eb2a37c
14("MLK-15109-2: ASoC: fsl_esai: add constrain_period_size")
15
16Signed-off-by: Mihai Serban <mihai.serban@nxp.com>
17Reviewed-by: Shengjiu Wang <shengjiu.wang@nxp.com>
18---
19 sound/soc/fsl/fsl_sai.c | 23 +++++++++++++++++++++++
20 sound/soc/fsl/fsl_sai.h | 2 ++
21 2 files changed, 25 insertions(+)
22
23--- a/sound/soc/fsl/fsl_sai.c
24+++ b/sound/soc/fsl/fsl_sai.c
25@@ -35,6 +35,7 @@ static struct fsl_sai_soc_data fsl_sai_v
26 .fifos = 1,
27 .fifo_depth = 32,
28 .flags = 0,
29+ .constrain_period_size = false,
30 };
31
32 static struct fsl_sai_soc_data fsl_sai_imx6sx = {
33@@ -44,6 +45,7 @@ static struct fsl_sai_soc_data fsl_sai_i
34 .fifo_depth = 32,
35 .flags = 0,
36 .reg_offset = 0,
37+ .constrain_period_size = false,
38 };
39
40 static struct fsl_sai_soc_data fsl_sai_imx6ul = {
41@@ -53,6 +55,7 @@ static struct fsl_sai_soc_data fsl_sai_i
42 .fifo_depth = 32,
43 .flags = 0,
44 .reg_offset = 0,
45+ .constrain_period_size = false,
46 };
47
48 static struct fsl_sai_soc_data fsl_sai_imx7ulp = {
49@@ -62,6 +65,7 @@ static struct fsl_sai_soc_data fsl_sai_i
50 .fifo_depth = 16,
51 .flags = SAI_FLAG_PMQOS,
52 .reg_offset = 0,
53+ .constrain_period_size = false,
54 };
55
56 static struct fsl_sai_soc_data fsl_sai_imx8mq = {
57@@ -71,6 +75,17 @@ static struct fsl_sai_soc_data fsl_sai_i
58 .fifo_depth = 32,
59 .flags = 0,
60 .reg_offset = 8,
61+ .constrain_period_size = false,
62+};
63+
64+static struct fsl_sai_soc_data fsl_sai_imx8qm = {
65+ .imx = true,
66+ .dataline = 0x3,
67+ .fifos = 1,
68+ .fifo_depth = 32,
69+ .flags = 0,
70+ .reg_offset = 0,
71+ .constrain_period_size = true,
72 };
73
74 static const unsigned int fsl_sai_rates[] = {
75@@ -693,6 +708,13 @@ static int fsl_sai_startup(struct snd_pc
76 FSL_SAI_CR3_TRCE_MASK,
77 FSL_SAI_CR3_TRCE(sai->dataline[tx]));
78
79+ /* EDMA engine needs periods of size multiple of tx/rx maxburst */
80+ if (sai->soc->constrain_period_size)
81+ snd_pcm_hw_constraint_step(substream->runtime, 0,
82+ SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
83+ tx ? sai->dma_params_tx.maxburst :
84+ sai->dma_params_rx.maxburst);
85+
86 ret = snd_pcm_hw_constraint_list(substream->runtime, 0,
87 SNDRV_PCM_HW_PARAM_RATE, &fsl_sai_rate_constraints);
88
89@@ -915,6 +937,7 @@ static const struct of_device_id fsl_sai
90 { .compatible = "fsl,imx6ul-sai", .data = &fsl_sai_imx6ul },
91 { .compatible = "fsl,imx7ulp-sai", .data = &fsl_sai_imx7ulp },
92 { .compatible = "fsl,imx8mq-sai", .data = &fsl_sai_imx8mq },
93+ { .compatible = "fsl,imx8qm-sai", .data = &fsl_sai_imx8qm },
94 { /* sentinel */ }
95 };
96 MODULE_DEVICE_TABLE(of, fsl_sai_ids);
97--- a/sound/soc/fsl/fsl_sai.h
98+++ b/sound/soc/fsl/fsl_sai.h
99@@ -147,6 +147,8 @@ struct fsl_sai_soc_data {
100 unsigned int flags;
101 unsigned char reg_offset;
102 bool imx;
103+ /* True for EDMA because it needs period size multiple of maxburst */
104+ bool constrain_period_size;
105 };
106
107 struct fsl_sai {