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 <drm/display/drm_hdmi_state_helper.h>
8 
9 #include <linux/hdmi.h>
10 
11 #include <sound/hdmi-codec.h>
12 
13 #include "hdmi.h"
14 
15 /* Supported HDMI Audio sample rates */
16 #define MSM_HDMI_SAMPLE_RATE_32KHZ		0
17 #define MSM_HDMI_SAMPLE_RATE_44_1KHZ		1
18 #define MSM_HDMI_SAMPLE_RATE_48KHZ		2
19 #define MSM_HDMI_SAMPLE_RATE_88_2KHZ		3
20 #define MSM_HDMI_SAMPLE_RATE_96KHZ		4
21 #define MSM_HDMI_SAMPLE_RATE_176_4KHZ		5
22 #define MSM_HDMI_SAMPLE_RATE_192KHZ		6
23 #define MSM_HDMI_SAMPLE_RATE_MAX		7
24 
25 
26 struct hdmi_msm_audio_acr {
27 	uint32_t n;	/* N parameter for clock regeneration */
28 	uint32_t cts;	/* CTS parameter for clock regeneration */
29 };
30 
31 struct hdmi_msm_audio_arcs {
32 	unsigned long int pixclock;
33 	struct hdmi_msm_audio_acr lut[MSM_HDMI_SAMPLE_RATE_MAX];
34 };
35 
36 #define HDMI_MSM_AUDIO_ARCS(pclk, ...) { (1000 * (pclk)), __VA_ARGS__ }
37 
38 /* Audio constants lookup table for hdmi_msm_audio_acr_setup */
39 /* Valid Pixel-Clock rates: 25.2MHz, 27MHz, 27.03MHz, 74.25MHz, 148.5MHz */
40 static const struct hdmi_msm_audio_arcs acr_lut[] = {
41 	/*  25.200MHz  */
42 	HDMI_MSM_AUDIO_ARCS(25200, {
43 		{4096, 25200}, {6272, 28000}, {6144, 25200}, {12544, 28000},
44 		{12288, 25200}, {25088, 28000}, {24576, 25200} }),
45 	/*  27.000MHz  */
46 	HDMI_MSM_AUDIO_ARCS(27000, {
47 		{4096, 27000}, {6272, 30000}, {6144, 27000}, {12544, 30000},
48 		{12288, 27000}, {25088, 30000}, {24576, 27000} }),
49 	/*  27.027MHz */
50 	HDMI_MSM_AUDIO_ARCS(27030, {
51 		{4096, 27027}, {6272, 30030}, {6144, 27027}, {12544, 30030},
52 		{12288, 27027}, {25088, 30030}, {24576, 27027} }),
53 	/*  74.250MHz */
54 	HDMI_MSM_AUDIO_ARCS(74250, {
55 		{4096, 74250}, {6272, 82500}, {6144, 74250}, {12544, 82500},
56 		{12288, 74250}, {25088, 82500}, {24576, 74250} }),
57 	/* 148.500MHz */
58 	HDMI_MSM_AUDIO_ARCS(148500, {
59 		{4096, 148500}, {6272, 165000}, {6144, 148500}, {12544, 165000},
60 		{12288, 148500}, {25088, 165000}, {24576, 148500} }),
61 };
62 
get_arcs(unsigned long int pixclock)63 static const struct hdmi_msm_audio_arcs *get_arcs(unsigned long int pixclock)
64 {
65 	int i;
66 
67 	for (i = 0; i < ARRAY_SIZE(acr_lut); i++) {
68 		const struct hdmi_msm_audio_arcs *arcs = &acr_lut[i];
69 		if (arcs->pixclock == pixclock)
70 			return arcs;
71 	}
72 
73 	return NULL;
74 }
75 
msm_hdmi_audio_update(struct hdmi * hdmi)76 int msm_hdmi_audio_update(struct hdmi *hdmi)
77 {
78 	struct hdmi_audio *audio = &hdmi->audio;
79 	const struct hdmi_msm_audio_arcs *arcs = NULL;
80 	bool enabled = audio->enabled;
81 	uint32_t acr_pkt_ctrl, vbi_pkt_ctrl, aud_pkt_ctrl;
82 	uint32_t audio_config;
83 
84 	if (!hdmi->connector->display_info.is_hdmi)
85 		return -EINVAL;
86 
87 	DBG("audio: enabled=%d, channels=%d, rate=%d",
88 	    audio->enabled, audio->channels, audio->rate);
89 
90 	DBG("video: power_on=%d, pixclock=%lu", hdmi->power_on, hdmi->pixclock);
91 
92 	if (enabled && !(hdmi->power_on && hdmi->pixclock)) {
93 		DBG("disabling audio: no video");
94 		enabled = false;
95 	}
96 
97 	if (enabled) {
98 		arcs = get_arcs(hdmi->pixclock);
99 		if (!arcs) {
100 			DBG("disabling audio: unsupported pixclock: %lu",
101 					hdmi->pixclock);
102 			enabled = false;
103 		}
104 	}
105 
106 	/* Read first before writing */
107 	acr_pkt_ctrl = hdmi_read(hdmi, REG_HDMI_ACR_PKT_CTRL);
108 	vbi_pkt_ctrl = hdmi_read(hdmi, REG_HDMI_VBI_PKT_CTRL);
109 	aud_pkt_ctrl = hdmi_read(hdmi, REG_HDMI_AUDIO_PKT_CTRL1);
110 	audio_config = hdmi_read(hdmi, REG_HDMI_AUDIO_CFG);
111 
112 	/* Clear N/CTS selection bits */
113 	acr_pkt_ctrl &= ~HDMI_ACR_PKT_CTRL_SELECT__MASK;
114 
115 	if (enabled) {
116 		uint32_t n, cts, multiplier;
117 		enum hdmi_acr_cts select;
118 
119 		n   = arcs->lut[audio->rate].n;
120 		cts = arcs->lut[audio->rate].cts;
121 
122 		if ((MSM_HDMI_SAMPLE_RATE_192KHZ == audio->rate) ||
123 				(MSM_HDMI_SAMPLE_RATE_176_4KHZ == audio->rate)) {
124 			multiplier = 4;
125 			n >>= 2; /* divide N by 4 and use multiplier */
126 		} else if ((MSM_HDMI_SAMPLE_RATE_96KHZ == audio->rate) ||
127 				(MSM_HDMI_SAMPLE_RATE_88_2KHZ == audio->rate)) {
128 			multiplier = 2;
129 			n >>= 1; /* divide N by 2 and use multiplier */
130 		} else {
131 			multiplier = 1;
132 		}
133 
134 		DBG("n=%u, cts=%u, multiplier=%u", n, cts, multiplier);
135 
136 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_SOURCE;
137 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_AUDIO_PRIORITY;
138 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_N_MULTIPLIER(multiplier);
139 
140 		if ((MSM_HDMI_SAMPLE_RATE_48KHZ == audio->rate) ||
141 				(MSM_HDMI_SAMPLE_RATE_96KHZ == audio->rate) ||
142 				(MSM_HDMI_SAMPLE_RATE_192KHZ == audio->rate))
143 			select = ACR_48;
144 		else if ((MSM_HDMI_SAMPLE_RATE_44_1KHZ == audio->rate) ||
145 				(MSM_HDMI_SAMPLE_RATE_88_2KHZ == audio->rate) ||
146 				(MSM_HDMI_SAMPLE_RATE_176_4KHZ == audio->rate))
147 			select = ACR_44;
148 		else /* default to 32k */
149 			select = ACR_32;
150 
151 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_SELECT(select);
152 
153 		hdmi_write(hdmi, REG_HDMI_ACR_0(select - 1),
154 				HDMI_ACR_0_CTS(cts));
155 		hdmi_write(hdmi, REG_HDMI_ACR_1(select - 1),
156 				HDMI_ACR_1_N(n));
157 
158 		hdmi_write(hdmi, REG_HDMI_AUDIO_PKT_CTRL2,
159 				COND(audio->channels != 2, HDMI_AUDIO_PKT_CTRL2_LAYOUT) |
160 				HDMI_AUDIO_PKT_CTRL2_OVERRIDE);
161 
162 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_CONT;
163 		acr_pkt_ctrl |= HDMI_ACR_PKT_CTRL_SEND;
164 
165 		hdmi_write(hdmi, REG_HDMI_GC, 0);
166 
167 		vbi_pkt_ctrl |= HDMI_VBI_PKT_CTRL_GC_ENABLE;
168 		vbi_pkt_ctrl |= HDMI_VBI_PKT_CTRL_GC_EVERY_FRAME;
169 
170 		aud_pkt_ctrl |= HDMI_AUDIO_PKT_CTRL1_AUDIO_SAMPLE_SEND;
171 
172 		audio_config &= ~HDMI_AUDIO_CFG_FIFO_WATERMARK__MASK;
173 		audio_config |= HDMI_AUDIO_CFG_FIFO_WATERMARK(4);
174 		audio_config |= HDMI_AUDIO_CFG_ENGINE_ENABLE;
175 	} else {
176 		acr_pkt_ctrl &= ~HDMI_ACR_PKT_CTRL_CONT;
177 		acr_pkt_ctrl &= ~HDMI_ACR_PKT_CTRL_SEND;
178 		vbi_pkt_ctrl &= ~HDMI_VBI_PKT_CTRL_GC_ENABLE;
179 		vbi_pkt_ctrl &= ~HDMI_VBI_PKT_CTRL_GC_EVERY_FRAME;
180 		aud_pkt_ctrl &= ~HDMI_AUDIO_PKT_CTRL1_AUDIO_SAMPLE_SEND;
181 		audio_config &= ~HDMI_AUDIO_CFG_ENGINE_ENABLE;
182 	}
183 
184 	hdmi_write(hdmi, REG_HDMI_ACR_PKT_CTRL, acr_pkt_ctrl);
185 	hdmi_write(hdmi, REG_HDMI_VBI_PKT_CTRL, vbi_pkt_ctrl);
186 	hdmi_write(hdmi, REG_HDMI_AUDIO_PKT_CTRL1, aud_pkt_ctrl);
187 
188 	hdmi_write(hdmi, REG_HDMI_AUD_INT,
189 			COND(enabled, HDMI_AUD_INT_AUD_FIFO_URUN_INT) |
190 			COND(enabled, HDMI_AUD_INT_AUD_SAM_DROP_INT));
191 
192 	hdmi_write(hdmi, REG_HDMI_AUDIO_CFG, audio_config);
193 
194 
195 	DBG("audio %sabled", enabled ? "en" : "dis");
196 
197 	return 0;
198 }
199 
msm_hdmi_bridge_audio_prepare(struct drm_connector * connector,struct drm_bridge * bridge,struct hdmi_codec_daifmt * daifmt,struct hdmi_codec_params * params)200 int msm_hdmi_bridge_audio_prepare(struct drm_connector *connector,
201 				  struct drm_bridge *bridge,
202 				  struct hdmi_codec_daifmt *daifmt,
203 				  struct hdmi_codec_params *params)
204 {
205 	struct hdmi_bridge *hdmi_bridge = to_hdmi_bridge(bridge);
206 	struct hdmi *hdmi = hdmi_bridge->hdmi;
207 	unsigned int rate;
208 	int ret;
209 
210 	drm_dbg_driver(bridge->dev, "%u Hz, %d bit, %d channels\n",
211 		       params->sample_rate,
212 		       params->sample_width,
213 		       params->cea.channels);
214 
215 	switch (params->sample_rate) {
216 	case 32000:
217 		rate = MSM_HDMI_SAMPLE_RATE_32KHZ;
218 		break;
219 	case 44100:
220 		rate = MSM_HDMI_SAMPLE_RATE_44_1KHZ;
221 		break;
222 	case 48000:
223 		rate = MSM_HDMI_SAMPLE_RATE_48KHZ;
224 		break;
225 	case 88200:
226 		rate = MSM_HDMI_SAMPLE_RATE_88_2KHZ;
227 		break;
228 	case 96000:
229 		rate = MSM_HDMI_SAMPLE_RATE_96KHZ;
230 		break;
231 	case 176400:
232 		rate = MSM_HDMI_SAMPLE_RATE_176_4KHZ;
233 		break;
234 	case 192000:
235 		rate = MSM_HDMI_SAMPLE_RATE_192KHZ;
236 		break;
237 	default:
238 		drm_err(bridge->dev, "rate[%d] not supported!\n",
239 			params->sample_rate);
240 		return -EINVAL;
241 	}
242 
243 	ret = drm_atomic_helper_connector_hdmi_update_audio_infoframe(connector,
244 								      &params->cea);
245 	if (ret)
246 		return ret;
247 
248 	hdmi->audio.rate = rate;
249 	hdmi->audio.channels = params->cea.channels;
250 	hdmi->audio.enabled = true;
251 
252 	return msm_hdmi_audio_update(hdmi);
253 }
254 
msm_hdmi_bridge_audio_shutdown(struct drm_connector * connector,struct drm_bridge * bridge)255 void msm_hdmi_bridge_audio_shutdown(struct drm_connector *connector,
256 				    struct drm_bridge *bridge)
257 {
258 	struct hdmi_bridge *hdmi_bridge = to_hdmi_bridge(bridge);
259 	struct hdmi *hdmi = hdmi_bridge->hdmi;
260 
261 	drm_atomic_helper_connector_hdmi_clear_audio_infoframe(connector);
262 
263 	hdmi->audio.rate = 0;
264 	hdmi->audio.channels = 2;
265 	hdmi->audio.enabled = false;
266 
267 	msm_hdmi_audio_update(hdmi);
268 }
269