xref: /openbmc/linux/drivers/gpu/drm/msm/hdmi/hdmi_audio.c (revision aa74c44b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2013 Red Hat
4  * Author: Rob Clark <robdclark@gmail.com>
5  */
6 
7 #include <linux/hdmi.h>
8 #include "hdmi.h"
9 
10 /* maps MSM_HDMI_AUDIO_CHANNEL_n consts used by audio driver to # of channels: */
11 static int nchannels[] = { 2, 4, 6, 8 };
12 
13 /* Supported HDMI Audio sample rates */
14 #define MSM_HDMI_SAMPLE_RATE_32KHZ		0
15 #define MSM_HDMI_SAMPLE_RATE_44_1KHZ		1
16 #define MSM_HDMI_SAMPLE_RATE_48KHZ		2
17 #define MSM_HDMI_SAMPLE_RATE_88_2KHZ		3
18 #define MSM_HDMI_SAMPLE_RATE_96KHZ		4
19 #define MSM_HDMI_SAMPLE_RATE_176_4KHZ		5
20 #define MSM_HDMI_SAMPLE_RATE_192KHZ		6
21 #define MSM_HDMI_SAMPLE_RATE_MAX		7
22 
23 
24 struct hdmi_msm_audio_acr {
25 	uint32_t n;	/* N parameter for clock regeneration */
26 	uint32_t cts;	/* CTS parameter for clock regeneration */
27 };
28 
29 struct hdmi_msm_audio_arcs {
30 	unsigned long int pixclock;
31 	struct hdmi_msm_audio_acr lut[MSM_HDMI_SAMPLE_RATE_MAX];
32 };
33 
34 #define HDMI_MSM_AUDIO_ARCS(pclk, ...) { (1000 * (pclk)), __VA_ARGS__ }
35 
36 /* Audio constants lookup table for hdmi_msm_audio_acr_setup */
37 /* Valid Pixel-Clock rates: 25.2MHz, 27MHz, 27.03MHz, 74.25MHz, 148.5MHz */
38 static const struct hdmi_msm_audio_arcs acr_lut[] = {
39 	/*  25.200MHz  */
40 	HDMI_MSM_AUDIO_ARCS(25200, {
41 		{4096, 25200}, {6272, 28000}, {6144, 25200}, {12544, 28000},
42 		{12288, 25200}, {25088, 28000}, {24576, 25200} }),
43 	/*  27.000MHz  */
44 	HDMI_MSM_AUDIO_ARCS(27000, {
45 		{4096, 27000}, {6272, 30000}, {6144, 27000}, {12544, 30000},
46 		{12288, 27000}, {25088, 30000}, {24576, 27000} }),
47 	/*  27.027MHz */
48 	HDMI_MSM_AUDIO_ARCS(27030, {
49 		{4096, 27027}, {6272, 30030}, {6144, 27027}, {12544, 30030},
50 		{12288, 27027}, {25088, 30030}, {24576, 27027} }),
51 	/*  74.250MHz */
52 	HDMI_MSM_AUDIO_ARCS(74250, {
53 		{4096, 74250}, {6272, 82500}, {6144, 74250}, {12544, 82500},
54 		{12288, 74250}, {25088, 82500}, {24576, 74250} }),
55 	/* 148.500MHz */
56 	HDMI_MSM_AUDIO_ARCS(148500, {
57 		{4096, 148500}, {6272, 165000}, {6144, 148500}, {12544, 165000},
58 		{12288, 148500}, {25088, 165000}, {24576, 148500} }),
59 };
60 
61 static const struct hdmi_msm_audio_arcs *get_arcs(unsigned long int pixclock)
62 {
63 	int i;
64 
65 	for (i = 0; i < ARRAY_SIZE(acr_lut); i++) {
66 		const struct hdmi_msm_audio_arcs *arcs = &acr_lut[i];
67 		if (arcs->pixclock == pixclock)
68 			return arcs;
69 	}
70 
71 	return NULL;
72 }
73 
74 int msm_hdmi_audio_update(struct hdmi *hdmi)
75 {
76 	struct hdmi_audio *audio = &hdmi->audio;
77 	struct hdmi_audio_infoframe *info = &audio->infoframe;
78 	const struct hdmi_msm_audio_arcs *arcs = NULL;
79 	bool enabled = audio->enabled;
80 	uint32_t acr_pkt_ctrl, vbi_pkt_ctrl, aud_pkt_ctrl;
81 	uint32_t infofrm_ctrl, audio_config;
82 
83 	DBG("audio: enabled=%d, channels=%d, channel_allocation=0x%x, "
84 		"level_shift_value=%d, downmix_inhibit=%d, rate=%d",
85 		audio->enabled, info->channels,  info->channel_allocation,
86 		info->level_shift_value, info->downmix_inhibit, audio->rate);
87 	DBG("video: power_on=%d, pixclock=%lu", hdmi->power_on, hdmi->pixclock);
88 
89 	if (enabled && !(hdmi->power_on && hdmi->pixclock)) {
90 		DBG("disabling audio: no video");
91 		enabled = false;
92 	}
93 
94 	if (enabled) {
95 		arcs = get_arcs(hdmi->pixclock);
96 		if (!arcs) {
97 			DBG("disabling audio: unsupported pixclock: %lu",
98 					hdmi->pixclock);
99 			enabled = false;
100 		}
101 	}
102 
103 	/* Read first before writing */
104 	acr_pkt_ctrl = hdmi_read(hdmi, REG_HDMI_ACR_PKT_CTRL);
105 	vbi_pkt_ctrl = hdmi_read(hdmi, REG_HDMI_VBI_PKT_CTRL);
106 	aud_pkt_ctrl = hdmi_read(hdmi, REG_HDMI_AUDIO_PKT_CTRL1);
107 	infofrm_ctrl = hdmi_read(hdmi, REG_HDMI_INFOFRAME_CTRL0);
108 	audio_config = hdmi_read(hdmi, REG_HDMI_AUDIO_CFG);
109 
110 	/* Clear N/CTS selection bits */
111 	acr_pkt_ctrl &= ~HDMI_ACR_PKT_CTRL_SELECT__MASK;
112 
113 	if (enabled) {
114 		uint32_t n, cts, multiplier;
115 		enum hdmi_acr_cts select;
116 		uint8_t buf[14];
117 
118 		n   = arcs->lut[audio->rate].n;
119 		cts = arcs->lut[audio->rate].cts;
120 
121 		if ((MSM_HDMI_SAMPLE_RATE_192KHZ == audio->rate) ||
122 				(MSM_HDMI_SAMPLE_RATE_176_4KHZ == audio->rate)) {
123 			multiplier = 4;
124 			n >>= 2; /* divide N by 4 and use multiplier */
125 		} else if ((MSM_HDMI_SAMPLE_RATE_96KHZ == audio->rate) ||
126 				(MSM_HDMI_SAMPLE_RATE_88_2KHZ == audio->rate)) {
127 			multiplier = 2;
128 			n >>= 1; /* divide N by 2 and use multiplier */
129 		} else {
130 			multiplier = 1;
131 		}
132 
133 		DBG("n=%u, cts=%u, multiplier=%u", n, cts, multiplier);
134 
135 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_SOURCE;
136 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_AUDIO_PRIORITY;
137 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_N_MULTIPLIER(multiplier);
138 
139 		if ((MSM_HDMI_SAMPLE_RATE_48KHZ == audio->rate) ||
140 				(MSM_HDMI_SAMPLE_RATE_96KHZ == audio->rate) ||
141 				(MSM_HDMI_SAMPLE_RATE_192KHZ == audio->rate))
142 			select = ACR_48;
143 		else if ((MSM_HDMI_SAMPLE_RATE_44_1KHZ == audio->rate) ||
144 				(MSM_HDMI_SAMPLE_RATE_88_2KHZ == audio->rate) ||
145 				(MSM_HDMI_SAMPLE_RATE_176_4KHZ == audio->rate))
146 			select = ACR_44;
147 		else /* default to 32k */
148 			select = ACR_32;
149 
150 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_SELECT(select);
151 
152 		hdmi_write(hdmi, REG_HDMI_ACR_0(select - 1),
153 				HDMI_ACR_0_CTS(cts));
154 		hdmi_write(hdmi, REG_HDMI_ACR_1(select - 1),
155 				HDMI_ACR_1_N(n));
156 
157 		hdmi_write(hdmi, REG_HDMI_AUDIO_PKT_CTRL2,
158 				COND(info->channels != 2, HDMI_AUDIO_PKT_CTRL2_LAYOUT) |
159 				HDMI_AUDIO_PKT_CTRL2_OVERRIDE);
160 
161 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_CONT;
162 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_SEND;
163 
164 		/* configure infoframe: */
165 		hdmi_audio_infoframe_pack(info, buf, sizeof(buf));
166 		hdmi_write(hdmi, REG_HDMI_AUDIO_INFO0,
167 				(buf[3] <<  0) | (buf[4] <<  8) |
168 				(buf[5] << 16) | (buf[6] << 24));
169 		hdmi_write(hdmi, REG_HDMI_AUDIO_INFO1,
170 				(buf[7] <<  0) | (buf[8] << 8));
171 
172 		hdmi_write(hdmi, REG_HDMI_GC, 0);
173 
174 		vbi_pkt_ctrl |= HDMI_VBI_PKT_CTRL_GC_ENABLE;
175 		vbi_pkt_ctrl |= HDMI_VBI_PKT_CTRL_GC_EVERY_FRAME;
176 
177 		aud_pkt_ctrl |= HDMI_AUDIO_PKT_CTRL1_AUDIO_SAMPLE_SEND;
178 
179 		infofrm_ctrl |= HDMI_INFOFRAME_CTRL0_AUDIO_INFO_SEND;
180 		infofrm_ctrl |= HDMI_INFOFRAME_CTRL0_AUDIO_INFO_CONT;
181 		infofrm_ctrl |= HDMI_INFOFRAME_CTRL0_AUDIO_INFO_SOURCE;
182 		infofrm_ctrl |= HDMI_INFOFRAME_CTRL0_AUDIO_INFO_UPDATE;
183 
184 		audio_config &= ~HDMI_AUDIO_CFG_FIFO_WATERMARK__MASK;
185 		audio_config |= HDMI_AUDIO_CFG_FIFO_WATERMARK(4);
186 		audio_config |= HDMI_AUDIO_CFG_ENGINE_ENABLE;
187 	} else {
188 		acr_pkt_ctrl &= ~HDMI_ACR_PKT_CTRL_CONT;
189 		acr_pkt_ctrl &= ~HDMI_ACR_PKT_CTRL_SEND;
190 		vbi_pkt_ctrl &= ~HDMI_VBI_PKT_CTRL_GC_ENABLE;
191 		vbi_pkt_ctrl &= ~HDMI_VBI_PKT_CTRL_GC_EVERY_FRAME;
192 		aud_pkt_ctrl &= ~HDMI_AUDIO_PKT_CTRL1_AUDIO_SAMPLE_SEND;
193 		infofrm_ctrl &= ~HDMI_INFOFRAME_CTRL0_AUDIO_INFO_SEND;
194 		infofrm_ctrl &= ~HDMI_INFOFRAME_CTRL0_AUDIO_INFO_CONT;
195 		infofrm_ctrl &= ~HDMI_INFOFRAME_CTRL0_AUDIO_INFO_SOURCE;
196 		infofrm_ctrl &= ~HDMI_INFOFRAME_CTRL0_AUDIO_INFO_UPDATE;
197 		audio_config &= ~HDMI_AUDIO_CFG_ENGINE_ENABLE;
198 	}
199 
200 	hdmi_write(hdmi, REG_HDMI_ACR_PKT_CTRL, acr_pkt_ctrl);
201 	hdmi_write(hdmi, REG_HDMI_VBI_PKT_CTRL, vbi_pkt_ctrl);
202 	hdmi_write(hdmi, REG_HDMI_AUDIO_PKT_CTRL1, aud_pkt_ctrl);
203 	hdmi_write(hdmi, REG_HDMI_INFOFRAME_CTRL0, infofrm_ctrl);
204 
205 	hdmi_write(hdmi, REG_HDMI_AUD_INT,
206 			COND(enabled, HDMI_AUD_INT_AUD_FIFO_URUN_INT) |
207 			COND(enabled, HDMI_AUD_INT_AUD_SAM_DROP_INT));
208 
209 	hdmi_write(hdmi, REG_HDMI_AUDIO_CFG, audio_config);
210 
211 
212 	DBG("audio %sabled", enabled ? "en" : "dis");
213 
214 	return 0;
215 }
216 
217 int msm_hdmi_audio_info_setup(struct hdmi *hdmi, bool enabled,
218 	uint32_t num_of_channels, uint32_t channel_allocation,
219 	uint32_t level_shift, bool down_mix)
220 {
221 	struct hdmi_audio *audio;
222 
223 	if (!hdmi)
224 		return -ENXIO;
225 
226 	audio = &hdmi->audio;
227 
228 	if (num_of_channels >= ARRAY_SIZE(nchannels))
229 		return -EINVAL;
230 
231 	audio->enabled = enabled;
232 	audio->infoframe.channels = nchannels[num_of_channels];
233 	audio->infoframe.channel_allocation = channel_allocation;
234 	audio->infoframe.level_shift_value = level_shift;
235 	audio->infoframe.downmix_inhibit = down_mix;
236 
237 	return msm_hdmi_audio_update(hdmi);
238 }
239 
240 void msm_hdmi_audio_set_sample_rate(struct hdmi *hdmi, int rate)
241 {
242 	struct hdmi_audio *audio;
243 
244 	if (!hdmi)
245 		return;
246 
247 	audio = &hdmi->audio;
248 
249 	if ((rate < 0) || (rate >= MSM_HDMI_SAMPLE_RATE_MAX))
250 		return;
251 
252 	audio->rate = rate;
253 	msm_hdmi_audio_update(hdmi);
254 }
255