xref: /openbmc/linux/drivers/gpu/drm/msm/hdmi/hdmi_audio.c (revision 7587eb18)
1 /*
2  * Copyright (C) 2013 Red Hat
3  * Author: Rob Clark <robdclark@gmail.com>
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 as published by
7  * the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program.  If not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 #include <linux/hdmi.h>
19 #include "hdmi.h"
20 
21 
22 /* Supported HDMI Audio channels */
23 #define MSM_HDMI_AUDIO_CHANNEL_2		0
24 #define MSM_HDMI_AUDIO_CHANNEL_4		1
25 #define MSM_HDMI_AUDIO_CHANNEL_6		2
26 #define MSM_HDMI_AUDIO_CHANNEL_8		3
27 
28 /* maps MSM_HDMI_AUDIO_CHANNEL_n consts used by audio driver to # of channels: */
29 static int nchannels[] = { 2, 4, 6, 8 };
30 
31 /* Supported HDMI Audio sample rates */
32 #define MSM_HDMI_SAMPLE_RATE_32KHZ		0
33 #define MSM_HDMI_SAMPLE_RATE_44_1KHZ		1
34 #define MSM_HDMI_SAMPLE_RATE_48KHZ		2
35 #define MSM_HDMI_SAMPLE_RATE_88_2KHZ		3
36 #define MSM_HDMI_SAMPLE_RATE_96KHZ		4
37 #define MSM_HDMI_SAMPLE_RATE_176_4KHZ		5
38 #define MSM_HDMI_SAMPLE_RATE_192KHZ		6
39 #define MSM_HDMI_SAMPLE_RATE_MAX		7
40 
41 
42 struct hdmi_msm_audio_acr {
43 	uint32_t n;	/* N parameter for clock regeneration */
44 	uint32_t cts;	/* CTS parameter for clock regeneration */
45 };
46 
47 struct hdmi_msm_audio_arcs {
48 	unsigned long int pixclock;
49 	struct hdmi_msm_audio_acr lut[MSM_HDMI_SAMPLE_RATE_MAX];
50 };
51 
52 #define HDMI_MSM_AUDIO_ARCS(pclk, ...) { (1000 * (pclk)), __VA_ARGS__ }
53 
54 /* Audio constants lookup table for hdmi_msm_audio_acr_setup */
55 /* Valid Pixel-Clock rates: 25.2MHz, 27MHz, 27.03MHz, 74.25MHz, 148.5MHz */
56 static const struct hdmi_msm_audio_arcs acr_lut[] = {
57 	/*  25.200MHz  */
58 	HDMI_MSM_AUDIO_ARCS(25200, {
59 		{4096, 25200}, {6272, 28000}, {6144, 25200}, {12544, 28000},
60 		{12288, 25200}, {25088, 28000}, {24576, 25200} }),
61 	/*  27.000MHz  */
62 	HDMI_MSM_AUDIO_ARCS(27000, {
63 		{4096, 27000}, {6272, 30000}, {6144, 27000}, {12544, 30000},
64 		{12288, 27000}, {25088, 30000}, {24576, 27000} }),
65 	/*  27.027MHz */
66 	HDMI_MSM_AUDIO_ARCS(27030, {
67 		{4096, 27027}, {6272, 30030}, {6144, 27027}, {12544, 30030},
68 		{12288, 27027}, {25088, 30030}, {24576, 27027} }),
69 	/*  74.250MHz */
70 	HDMI_MSM_AUDIO_ARCS(74250, {
71 		{4096, 74250}, {6272, 82500}, {6144, 74250}, {12544, 82500},
72 		{12288, 74250}, {25088, 82500}, {24576, 74250} }),
73 	/* 148.500MHz */
74 	HDMI_MSM_AUDIO_ARCS(148500, {
75 		{4096, 148500}, {6272, 165000}, {6144, 148500}, {12544, 165000},
76 		{12288, 148500}, {25088, 165000}, {24576, 148500} }),
77 };
78 
79 static const struct hdmi_msm_audio_arcs *get_arcs(unsigned long int pixclock)
80 {
81 	int i;
82 
83 	for (i = 0; i < ARRAY_SIZE(acr_lut); i++) {
84 		const struct hdmi_msm_audio_arcs *arcs = &acr_lut[i];
85 		if (arcs->pixclock == pixclock)
86 			return arcs;
87 	}
88 
89 	return NULL;
90 }
91 
92 int msm_hdmi_audio_update(struct hdmi *hdmi)
93 {
94 	struct hdmi_audio *audio = &hdmi->audio;
95 	struct hdmi_audio_infoframe *info = &audio->infoframe;
96 	const struct hdmi_msm_audio_arcs *arcs = NULL;
97 	bool enabled = audio->enabled;
98 	uint32_t acr_pkt_ctrl, vbi_pkt_ctrl, aud_pkt_ctrl;
99 	uint32_t infofrm_ctrl, audio_config;
100 
101 	DBG("audio: enabled=%d, channels=%d, channel_allocation=0x%x, "
102 		"level_shift_value=%d, downmix_inhibit=%d, rate=%d",
103 		audio->enabled, info->channels,  info->channel_allocation,
104 		info->level_shift_value, info->downmix_inhibit, audio->rate);
105 	DBG("video: power_on=%d, pixclock=%lu", hdmi->power_on, hdmi->pixclock);
106 
107 	if (enabled && !(hdmi->power_on && hdmi->pixclock)) {
108 		DBG("disabling audio: no video");
109 		enabled = false;
110 	}
111 
112 	if (enabled) {
113 		arcs = get_arcs(hdmi->pixclock);
114 		if (!arcs) {
115 			DBG("disabling audio: unsupported pixclock: %lu",
116 					hdmi->pixclock);
117 			enabled = false;
118 		}
119 	}
120 
121 	/* Read first before writing */
122 	acr_pkt_ctrl = hdmi_read(hdmi, REG_HDMI_ACR_PKT_CTRL);
123 	vbi_pkt_ctrl = hdmi_read(hdmi, REG_HDMI_VBI_PKT_CTRL);
124 	aud_pkt_ctrl = hdmi_read(hdmi, REG_HDMI_AUDIO_PKT_CTRL1);
125 	infofrm_ctrl = hdmi_read(hdmi, REG_HDMI_INFOFRAME_CTRL0);
126 	audio_config = hdmi_read(hdmi, REG_HDMI_AUDIO_CFG);
127 
128 	/* Clear N/CTS selection bits */
129 	acr_pkt_ctrl &= ~HDMI_ACR_PKT_CTRL_SELECT__MASK;
130 
131 	if (enabled) {
132 		uint32_t n, cts, multiplier;
133 		enum hdmi_acr_cts select;
134 		uint8_t buf[14];
135 
136 		n   = arcs->lut[audio->rate].n;
137 		cts = arcs->lut[audio->rate].cts;
138 
139 		if ((MSM_HDMI_SAMPLE_RATE_192KHZ == audio->rate) ||
140 				(MSM_HDMI_SAMPLE_RATE_176_4KHZ == audio->rate)) {
141 			multiplier = 4;
142 			n >>= 2; /* divide N by 4 and use multiplier */
143 		} else if ((MSM_HDMI_SAMPLE_RATE_96KHZ == audio->rate) ||
144 				(MSM_HDMI_SAMPLE_RATE_88_2KHZ == audio->rate)) {
145 			multiplier = 2;
146 			n >>= 1; /* divide N by 2 and use multiplier */
147 		} else {
148 			multiplier = 1;
149 		}
150 
151 		DBG("n=%u, cts=%u, multiplier=%u", n, cts, multiplier);
152 
153 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_SOURCE;
154 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_AUDIO_PRIORITY;
155 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_N_MULTIPLIER(multiplier);
156 
157 		if ((MSM_HDMI_SAMPLE_RATE_48KHZ == audio->rate) ||
158 				(MSM_HDMI_SAMPLE_RATE_96KHZ == audio->rate) ||
159 				(MSM_HDMI_SAMPLE_RATE_192KHZ == audio->rate))
160 			select = ACR_48;
161 		else if ((MSM_HDMI_SAMPLE_RATE_44_1KHZ == audio->rate) ||
162 				(MSM_HDMI_SAMPLE_RATE_88_2KHZ == audio->rate) ||
163 				(MSM_HDMI_SAMPLE_RATE_176_4KHZ == audio->rate))
164 			select = ACR_44;
165 		else /* default to 32k */
166 			select = ACR_32;
167 
168 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_SELECT(select);
169 
170 		hdmi_write(hdmi, REG_HDMI_ACR_0(select - 1),
171 				HDMI_ACR_0_CTS(cts));
172 		hdmi_write(hdmi, REG_HDMI_ACR_1(select - 1),
173 				HDMI_ACR_1_N(n));
174 
175 		hdmi_write(hdmi, REG_HDMI_AUDIO_PKT_CTRL2,
176 				COND(info->channels != 2, HDMI_AUDIO_PKT_CTRL2_LAYOUT) |
177 				HDMI_AUDIO_PKT_CTRL2_OVERRIDE);
178 
179 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_CONT;
180 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_SEND;
181 
182 		/* configure infoframe: */
183 		hdmi_audio_infoframe_pack(info, buf, sizeof(buf));
184 		hdmi_write(hdmi, REG_HDMI_AUDIO_INFO0,
185 				(buf[3] <<  0) || (buf[4] <<  8) ||
186 				(buf[5] << 16) || (buf[6] << 24));
187 		hdmi_write(hdmi, REG_HDMI_AUDIO_INFO1,
188 				(buf[7] <<  0) || (buf[8] << 8));
189 
190 		hdmi_write(hdmi, REG_HDMI_GC, 0);
191 
192 		vbi_pkt_ctrl |= HDMI_VBI_PKT_CTRL_GC_ENABLE;
193 		vbi_pkt_ctrl |= HDMI_VBI_PKT_CTRL_GC_EVERY_FRAME;
194 
195 		aud_pkt_ctrl |= HDMI_AUDIO_PKT_CTRL1_AUDIO_SAMPLE_SEND;
196 
197 		infofrm_ctrl |= HDMI_INFOFRAME_CTRL0_AUDIO_INFO_SEND;
198 		infofrm_ctrl |= HDMI_INFOFRAME_CTRL0_AUDIO_INFO_CONT;
199 		infofrm_ctrl |= HDMI_INFOFRAME_CTRL0_AUDIO_INFO_SOURCE;
200 		infofrm_ctrl |= HDMI_INFOFRAME_CTRL0_AUDIO_INFO_UPDATE;
201 
202 		audio_config &= ~HDMI_AUDIO_CFG_FIFO_WATERMARK__MASK;
203 		audio_config |= HDMI_AUDIO_CFG_FIFO_WATERMARK(4);
204 		audio_config |= HDMI_AUDIO_CFG_ENGINE_ENABLE;
205 	} else {
206 		acr_pkt_ctrl &= ~HDMI_ACR_PKT_CTRL_CONT;
207 		acr_pkt_ctrl &= ~HDMI_ACR_PKT_CTRL_SEND;
208 		vbi_pkt_ctrl &= ~HDMI_VBI_PKT_CTRL_GC_ENABLE;
209 		vbi_pkt_ctrl &= ~HDMI_VBI_PKT_CTRL_GC_EVERY_FRAME;
210 		aud_pkt_ctrl &= ~HDMI_AUDIO_PKT_CTRL1_AUDIO_SAMPLE_SEND;
211 		infofrm_ctrl &= ~HDMI_INFOFRAME_CTRL0_AUDIO_INFO_SEND;
212 		infofrm_ctrl &= ~HDMI_INFOFRAME_CTRL0_AUDIO_INFO_CONT;
213 		infofrm_ctrl &= ~HDMI_INFOFRAME_CTRL0_AUDIO_INFO_SOURCE;
214 		infofrm_ctrl &= ~HDMI_INFOFRAME_CTRL0_AUDIO_INFO_UPDATE;
215 		audio_config &= ~HDMI_AUDIO_CFG_ENGINE_ENABLE;
216 	}
217 
218 	hdmi_write(hdmi, REG_HDMI_ACR_PKT_CTRL, acr_pkt_ctrl);
219 	hdmi_write(hdmi, REG_HDMI_VBI_PKT_CTRL, vbi_pkt_ctrl);
220 	hdmi_write(hdmi, REG_HDMI_AUDIO_PKT_CTRL1, aud_pkt_ctrl);
221 	hdmi_write(hdmi, REG_HDMI_INFOFRAME_CTRL0, infofrm_ctrl);
222 
223 	hdmi_write(hdmi, REG_HDMI_AUD_INT,
224 			COND(enabled, HDMI_AUD_INT_AUD_FIFO_URUN_INT) |
225 			COND(enabled, HDMI_AUD_INT_AUD_SAM_DROP_INT));
226 
227 	hdmi_write(hdmi, REG_HDMI_AUDIO_CFG, audio_config);
228 
229 
230 	DBG("audio %sabled", enabled ? "en" : "dis");
231 
232 	return 0;
233 }
234 
235 int msm_hdmi_audio_info_setup(struct hdmi *hdmi, bool enabled,
236 	uint32_t num_of_channels, uint32_t channel_allocation,
237 	uint32_t level_shift, bool down_mix)
238 {
239 	struct hdmi_audio *audio;
240 
241 	if (!hdmi)
242 		return -ENXIO;
243 
244 	audio = &hdmi->audio;
245 
246 	if (num_of_channels >= ARRAY_SIZE(nchannels))
247 		return -EINVAL;
248 
249 	audio->enabled = enabled;
250 	audio->infoframe.channels = nchannels[num_of_channels];
251 	audio->infoframe.channel_allocation = channel_allocation;
252 	audio->infoframe.level_shift_value = level_shift;
253 	audio->infoframe.downmix_inhibit = down_mix;
254 
255 	return msm_hdmi_audio_update(hdmi);
256 }
257 
258 void msm_hdmi_audio_set_sample_rate(struct hdmi *hdmi, int rate)
259 {
260 	struct hdmi_audio *audio;
261 
262 	if (!hdmi)
263 		return;
264 
265 	audio = &hdmi->audio;
266 
267 	if ((rate < 0) || (rate >= MSM_HDMI_SAMPLE_RATE_MAX))
268 		return;
269 
270 	audio->rate = rate;
271 	msm_hdmi_audio_update(hdmi);
272 }
273