1 // SPDX-License-Identifier: (GPL-2.0+ OR MIT)
2 /*
3  * dw-hdmi-gp-audio.c
4  *
5  * Copyright 2020-2022 NXP
6  */
7 #include <linux/io.h>
8 #include <linux/interrupt.h>
9 #include <linux/module.h>
10 #include <linux/platform_device.h>
11 #include <linux/dmaengine.h>
12 #include <linux/dma-mapping.h>
13 #include <drm/bridge/dw_hdmi.h>
14 #include <drm/drm_edid.h>
15 #include <drm/drm_connector.h>
16 
17 #include <sound/hdmi-codec.h>
18 #include <sound/asoundef.h>
19 #include <sound/core.h>
20 #include <sound/initval.h>
21 #include <sound/pcm.h>
22 #include <sound/pcm_drm_eld.h>
23 #include <sound/pcm_iec958.h>
24 #include <sound/dmaengine_pcm.h>
25 
26 #include "dw-hdmi-audio.h"
27 
28 #define DRIVER_NAME "dw-hdmi-gp-audio"
29 #define DRV_NAME    "hdmi-gp-audio"
30 
31 struct snd_dw_hdmi {
32 	struct dw_hdmi_audio_data data;
33 	struct platform_device  *audio_pdev;
34 	unsigned int pos;
35 };
36 
37 struct dw_hdmi_channel_conf {
38 	u8 conf1;
39 	u8 ca;
40 };
41 
42 /*
43  * The default mapping of ALSA channels to HDMI channels and speaker
44  * allocation bits.  Note that we can't do channel remapping here -
45  * channels must be in the same order.
46  *
47  * Mappings for alsa-lib pcm/surround*.conf files:
48  *
49  *		Front	Sur4.0	Sur4.1	Sur5.0	Sur5.1	Sur7.1
50  * Channels	2	4	6	6	6	8
51  *
52  * Our mapping from ALSA channel to CEA686D speaker name and HDMI channel:
53  *
54  *				Number of ALSA channels
55  * ALSA Channel	2	3	4	5	6	7	8
56  * 0		FL:0	=	=	=	=	=	=
57  * 1		FR:1	=	=	=	=	=	=
58  * 2			FC:3	RL:4	LFE:2	=	=	=
59  * 3				RR:5	RL:4	FC:3	=	=
60  * 4					RR:5	RL:4	=	=
61  * 5						RR:5	=	=
62  * 6							RC:6	=
63  * 7							RLC/FRC	RLC/FRC
64  */
65 static struct dw_hdmi_channel_conf default_hdmi_channel_config[7] = {
66 	{ 0x03, 0x00 },	/* FL,FR */
67 	{ 0x0b, 0x02 },	/* FL,FR,FC */
68 	{ 0x33, 0x08 },	/* FL,FR,RL,RR */
69 	{ 0x37, 0x09 },	/* FL,FR,LFE,RL,RR */
70 	{ 0x3f, 0x0b },	/* FL,FR,LFE,FC,RL,RR */
71 	{ 0x7f, 0x0f },	/* FL,FR,LFE,FC,RL,RR,RC */
72 	{ 0xff, 0x13 },	/* FL,FR,LFE,FC,RL,RR,[FR]RC,[FR]LC */
73 };
74 
75 static int audio_hw_params(struct device *dev,  void *data,
76 			   struct hdmi_codec_daifmt *daifmt,
77 			   struct hdmi_codec_params *params)
78 {
79 	struct snd_dw_hdmi *dw = dev_get_drvdata(dev);
80 	int ret = 0;
81 	u8 ca;
82 
83 	dw_hdmi_set_sample_rate(dw->data.hdmi, params->sample_rate);
84 
85 	ca = default_hdmi_channel_config[params->channels - 2].ca;
86 
87 	dw_hdmi_set_channel_count(dw->data.hdmi, params->channels);
88 	dw_hdmi_set_channel_allocation(dw->data.hdmi, ca);
89 
90 	dw_hdmi_set_sample_non_pcm(dw->data.hdmi,
91 				   params->iec.status[0] & IEC958_AES0_NONAUDIO);
92 	dw_hdmi_set_sample_width(dw->data.hdmi, params->sample_width);
93 
94 	return ret;
95 }
96 
97 static void audio_shutdown(struct device *dev, void *data)
98 {
99 }
100 
101 static int audio_mute_stream(struct device *dev, void *data,
102 			     bool enable, int direction)
103 {
104 	struct snd_dw_hdmi *dw = dev_get_drvdata(dev);
105 	int ret = 0;
106 
107 	if (!enable)
108 		dw_hdmi_audio_enable(dw->data.hdmi);
109 	else
110 		dw_hdmi_audio_disable(dw->data.hdmi);
111 
112 	return ret;
113 }
114 
115 static int audio_get_eld(struct device *dev, void *data,
116 			 u8 *buf, size_t len)
117 {
118 	struct dw_hdmi_audio_data *audio = data;
119 	u8 *eld;
120 
121 	eld = audio->get_eld(audio->hdmi);
122 	if (eld)
123 		memcpy(buf, eld, min_t(size_t, MAX_ELD_BYTES, len));
124 	else
125 		/* Pass en empty ELD if connector not available */
126 		memset(buf, 0, len);
127 
128 	return 0;
129 }
130 
131 static int audio_hook_plugged_cb(struct device *dev, void *data,
132 				 hdmi_codec_plugged_cb fn,
133 				 struct device *codec_dev)
134 {
135 	struct snd_dw_hdmi *dw = dev_get_drvdata(dev);
136 
137 	return dw_hdmi_set_plugged_cb(dw->data.hdmi, fn, codec_dev);
138 }
139 
140 static const struct hdmi_codec_ops audio_codec_ops = {
141 	.hw_params = audio_hw_params,
142 	.audio_shutdown = audio_shutdown,
143 	.mute_stream = audio_mute_stream,
144 	.get_eld = audio_get_eld,
145 	.hook_plugged_cb = audio_hook_plugged_cb,
146 };
147 
148 static int snd_dw_hdmi_probe(struct platform_device *pdev)
149 {
150 	struct dw_hdmi_audio_data *data = pdev->dev.platform_data;
151 	struct snd_dw_hdmi *dw;
152 
153 	const struct hdmi_codec_pdata codec_data = {
154 		.i2s = 1,
155 		.spdif = 0,
156 		.ops = &audio_codec_ops,
157 		.max_i2s_channels = 8,
158 		.data = data,
159 	};
160 
161 	dw = devm_kzalloc(&pdev->dev, sizeof(*dw), GFP_KERNEL);
162 	if (!dw)
163 		return -ENOMEM;
164 
165 	dw->data = *data;
166 
167 	platform_set_drvdata(pdev, dw);
168 
169 	dw->audio_pdev = platform_device_register_data(&pdev->dev,
170 						       HDMI_CODEC_DRV_NAME, 1,
171 						       &codec_data,
172 						       sizeof(codec_data));
173 
174 	return PTR_ERR_OR_ZERO(dw->audio_pdev);
175 }
176 
177 static int snd_dw_hdmi_remove(struct platform_device *pdev)
178 {
179 	struct snd_dw_hdmi *dw = platform_get_drvdata(pdev);
180 
181 	platform_device_unregister(dw->audio_pdev);
182 
183 	return 0;
184 }
185 
186 static struct platform_driver snd_dw_hdmi_driver = {
187 	.probe	= snd_dw_hdmi_probe,
188 	.remove	= snd_dw_hdmi_remove,
189 	.driver	= {
190 		.name = DRIVER_NAME,
191 	},
192 };
193 
194 module_platform_driver(snd_dw_hdmi_driver);
195 
196 MODULE_AUTHOR("Shengjiu Wang <shengjiu.wang@nxp.com>");
197 MODULE_DESCRIPTION("Synopsys Designware HDMI GPA ALSA interface");
198 MODULE_LICENSE("GPL");
199 MODULE_ALIAS("platform:" DRIVER_NAME);
200