1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (c) 2020 BayLibre, SAS.
4 // Author: Jerome Brunet <jbrunet@baylibre.com>
5
6 #include <linux/bitfield.h>
7 #include <linux/clk.h>
8 #include <sound/pcm_params.h>
9 #include <sound/pcm_iec958.h>
10 #include <sound/soc.h>
11 #include <sound/soc-dai.h>
12
13 #include "aiu.h"
14
15 #define AIU_958_MISC_NON_PCM BIT(0)
16 #define AIU_958_MISC_MODE_16BITS BIT(1)
17 #define AIU_958_MISC_16BITS_ALIGN GENMASK(6, 5)
18 #define AIU_958_MISC_MODE_32BITS BIT(7)
19 #define AIU_958_MISC_U_FROM_STREAM BIT(12)
20 #define AIU_958_MISC_FORCE_LR BIT(13)
21 #define AIU_958_CTRL_HOLD_EN BIT(0)
22 #define AIU_CLK_CTRL_958_DIV_EN BIT(1)
23 #define AIU_CLK_CTRL_958_DIV GENMASK(5, 4)
24 #define AIU_CLK_CTRL_958_DIV_MORE BIT(12)
25
26 #define AIU_CS_WORD_LEN 4
27 #define AIU_958_INTERNAL_DIV 2
28
29 static void
30 aiu_encoder_spdif_divider_enable(struct snd_soc_component *component,
31 bool enable)
32 {
33 snd_soc_component_update_bits(component, AIU_CLK_CTRL,
34 AIU_CLK_CTRL_958_DIV_EN,
35 enable ? AIU_CLK_CTRL_958_DIV_EN : 0);
36 }
37
38 static void aiu_encoder_spdif_hold(struct snd_soc_component *component,
39 bool enable)
40 {
41 snd_soc_component_update_bits(component, AIU_958_CTRL,
42 AIU_958_CTRL_HOLD_EN,
43 enable ? AIU_958_CTRL_HOLD_EN : 0);
44 }
45
46 static int
47 aiu_encoder_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
48 struct snd_soc_dai *dai)
49 {
50 struct snd_soc_component *component = dai->component;
51
52 switch (cmd) {
53 case SNDRV_PCM_TRIGGER_START:
54 case SNDRV_PCM_TRIGGER_RESUME:
55 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
56 aiu_encoder_spdif_hold(component, false);
57 return 0;
58
59 case SNDRV_PCM_TRIGGER_STOP:
60 case SNDRV_PCM_TRIGGER_SUSPEND:
61 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
62 aiu_encoder_spdif_hold(component, true);
63 return 0;
64
65 default:
66 return -EINVAL;
67 }
68 }
69
70 static int aiu_encoder_spdif_setup_cs_word(struct snd_soc_component *component,
71 struct snd_pcm_hw_params *params)
72 {
73 u8 cs[AIU_CS_WORD_LEN];
74 unsigned int val;
75 int ret;
76
77 ret = snd_pcm_create_iec958_consumer_hw_params(params, cs,
78 AIU_CS_WORD_LEN);
79 if (ret < 0)
80 return ret;
81
82 /* Write the 1st half word */
83 val = cs[1] | cs[0] << 8;
84 snd_soc_component_write(component, AIU_958_CHSTAT_L0, val);
85 snd_soc_component_write(component, AIU_958_CHSTAT_R0, val);
86
87 /* Write the 2nd half word */
88 val = cs[3] | cs[2] << 8;
89 snd_soc_component_write(component, AIU_958_CHSTAT_L1, val);
90 snd_soc_component_write(component, AIU_958_CHSTAT_R1, val);
91
92 return 0;
93 }
94
95 static int aiu_encoder_spdif_hw_params(struct snd_pcm_substream *substream,
96 struct snd_pcm_hw_params *params,
97 struct snd_soc_dai *dai)
98 {
99 struct snd_soc_component *component = dai->component;
100 struct aiu *aiu = snd_soc_component_get_drvdata(component);
101 unsigned int val = 0, mrate;
102 int ret;
103
104 /* Disable the clock while changing the settings */
105 aiu_encoder_spdif_divider_enable(component, false);
106
107 switch (params_physical_width(params)) {
108 case 16:
109 val |= AIU_958_MISC_MODE_16BITS;
110 val |= FIELD_PREP(AIU_958_MISC_16BITS_ALIGN, 2);
111 break;
112 case 32:
113 val |= AIU_958_MISC_MODE_32BITS;
114 break;
115 default:
116 dev_err(dai->dev, "Unsupported physical width\n");
117 return -EINVAL;
118 }
119
120 snd_soc_component_update_bits(component, AIU_958_MISC,
121 AIU_958_MISC_NON_PCM |
122 AIU_958_MISC_MODE_16BITS |
123 AIU_958_MISC_16BITS_ALIGN |
124 AIU_958_MISC_MODE_32BITS |
125 AIU_958_MISC_FORCE_LR |
126 AIU_958_MISC_U_FROM_STREAM,
127 val);
128
129 /* Set the stream channel status word */
130 ret = aiu_encoder_spdif_setup_cs_word(component, params);
131 if (ret) {
132 dev_err(dai->dev, "failed to set channel status word\n");
133 return ret;
134 }
135
136 snd_soc_component_update_bits(component, AIU_CLK_CTRL,
137 AIU_CLK_CTRL_958_DIV |
138 AIU_CLK_CTRL_958_DIV_MORE,
139 FIELD_PREP(AIU_CLK_CTRL_958_DIV,
140 __ffs(AIU_958_INTERNAL_DIV)));
141
142 /* 2 * 32bits per subframe * 2 channels = 128 */
143 mrate = params_rate(params) * 128 * AIU_958_INTERNAL_DIV;
144 ret = clk_set_rate(aiu->spdif.clks[MCLK].clk, mrate);
145 if (ret) {
146 dev_err(dai->dev, "failed to set mclk rate\n");
147 return ret;
148 }
149
150 aiu_encoder_spdif_divider_enable(component, true);
151
152 return 0;
153 }
154
155 static int aiu_encoder_spdif_hw_free(struct snd_pcm_substream *substream,
156 struct snd_soc_dai *dai)
157 {
158 struct snd_soc_component *component = dai->component;
159
160 aiu_encoder_spdif_divider_enable(component, false);
161
162 return 0;
163 }
164
165 static int aiu_encoder_spdif_startup(struct snd_pcm_substream *substream,
166 struct snd_soc_dai *dai)
167 {
168 struct aiu *aiu = snd_soc_component_get_drvdata(dai->component);
169 int ret;
170
171 /*
172 * NOTE: Make sure the spdif block is on its own divider.
173 *
174 * The spdif can be clocked by the i2s master clock or its own
175 * clock. We should (in theory) change the source depending on the
176 * origin of the data.
177 *
178 * However, considering the clocking scheme used on these platforms,
179 * the master clocks will pick the same PLL source when they are
180 * playing from the same FIFO. The clock should be in sync so, it
181 * should not be necessary to reparent the spdif master clock.
182 */
183 ret = clk_set_parent(aiu->spdif.clks[MCLK].clk,
184 aiu->spdif_mclk);
185 if (ret)
186 return ret;
187
188 ret = clk_bulk_prepare_enable(aiu->spdif.clk_num, aiu->spdif.clks);
189 if (ret)
190 dev_err(dai->dev, "failed to enable spdif clocks\n");
191
192 return ret;
193 }
194
195 static void aiu_encoder_spdif_shutdown(struct snd_pcm_substream *substream,
196 struct snd_soc_dai *dai)
197 {
198 struct aiu *aiu = snd_soc_component_get_drvdata(dai->component);
199
200 clk_bulk_disable_unprepare(aiu->spdif.clk_num, aiu->spdif.clks);
201 }
202
203 const struct snd_soc_dai_ops aiu_encoder_spdif_dai_ops = {
204 .trigger = aiu_encoder_spdif_trigger,
205 .hw_params = aiu_encoder_spdif_hw_params,
206 .hw_free = aiu_encoder_spdif_hw_free,
207 .startup = aiu_encoder_spdif_startup,
208 .shutdown = aiu_encoder_spdif_shutdown,
209 };
210
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