1 /* SPDX-License-Identifier: GPL-2.0
2  *
3  * linux/sound/soc-dpcm.h -- ALSA SoC Dynamic PCM Support
4  *
5  * Author:		Liam Girdwood <lrg@ti.com>
6  */
7 
8 #ifndef __LINUX_SND_SOC_DPCM_H
9 #define __LINUX_SND_SOC_DPCM_H
10 
11 #include <linux/slab.h>
12 #include <linux/list.h>
13 #include <sound/pcm.h>
14 
15 struct snd_soc_pcm_runtime;
16 
17 /*
18  * Types of runtime_update to perform. e.g. originated from FE PCM ops
19  * or audio route changes triggered by muxes/mixers.
20  */
21 enum snd_soc_dpcm_update {
22 	SND_SOC_DPCM_UPDATE_NO	= 0,
23 	SND_SOC_DPCM_UPDATE_BE,
24 	SND_SOC_DPCM_UPDATE_FE,
25 };
26 
27 /*
28  * Dynamic PCM Frontend -> Backend link management states.
29  */
30 enum snd_soc_dpcm_link_state {
31 	SND_SOC_DPCM_LINK_STATE_NEW	= 0,	/* newly created link */
32 	SND_SOC_DPCM_LINK_STATE_FREE,		/* link to be dismantled */
33 };
34 
35 /*
36  * Dynamic PCM Frontend -> Backend link PCM states.
37  */
38 enum snd_soc_dpcm_state {
39 	SND_SOC_DPCM_STATE_NEW	= 0,
40 	SND_SOC_DPCM_STATE_OPEN,
41 	SND_SOC_DPCM_STATE_HW_PARAMS,
42 	SND_SOC_DPCM_STATE_PREPARE,
43 	SND_SOC_DPCM_STATE_START,
44 	SND_SOC_DPCM_STATE_STOP,
45 	SND_SOC_DPCM_STATE_PAUSED,
46 	SND_SOC_DPCM_STATE_SUSPEND,
47 	SND_SOC_DPCM_STATE_HW_FREE,
48 	SND_SOC_DPCM_STATE_CLOSE,
49 };
50 
51 /*
52  * Dynamic PCM trigger ordering. Triggering flexibility is required as some
53  * DSPs require triggering before/after their CPU platform and DAIs.
54  *
55  * i.e. some clients may want to manually order this call in their PCM
56  * trigger() whilst others will just use the regular core ordering.
57  */
58 enum snd_soc_dpcm_trigger {
59 	SND_SOC_DPCM_TRIGGER_PRE		= 0,
60 	SND_SOC_DPCM_TRIGGER_POST,
61 	SND_SOC_DPCM_TRIGGER_BESPOKE,
62 };
63 
64 /*
65  * Dynamic PCM link
66  * This links together a FE and BE DAI at runtime and stores the link
67  * state information and the hw_params configuration.
68  */
69 struct snd_soc_dpcm {
70 	/* FE and BE DAIs*/
71 	struct snd_soc_pcm_runtime *be;
72 	struct snd_soc_pcm_runtime *fe;
73 
74 	/* link state */
75 	enum snd_soc_dpcm_link_state state;
76 
77 	/* list of BE and FE for this DPCM link */
78 	struct list_head list_be;
79 	struct list_head list_fe;
80 
81 	/* hw params for this link - may be different for each link */
82 	struct snd_pcm_hw_params hw_params;
83 #ifdef CONFIG_DEBUG_FS
84 	struct dentry *debugfs_state;
85 #endif
86 };
87 
88 /*
89  * Dynamic PCM runtime data.
90  */
91 struct snd_soc_dpcm_runtime {
92 	struct list_head be_clients;
93 	struct list_head fe_clients;
94 
95 	int users;
96 	struct snd_pcm_runtime *runtime;
97 	struct snd_pcm_hw_params hw_params;
98 
99 	/* state and update */
100 	enum snd_soc_dpcm_update runtime_update;
101 	enum snd_soc_dpcm_state state;
102 
103 	int trigger_pending; /* trigger cmd + 1 if pending, 0 if not */
104 
105 	int be_start; /* refcount protected by BE stream pcm lock */
106 	int be_pause; /* refcount protected by BE stream pcm lock */
107 	bool fe_pause; /* used to track STOP after PAUSE */
108 };
109 
110 #define for_each_dpcm_fe(be, stream, _dpcm)				\
111 	list_for_each_entry(_dpcm, &(be)->dpcm[stream].fe_clients, list_fe)
112 
113 #define for_each_dpcm_be(fe, stream, _dpcm)				\
114 	list_for_each_entry(_dpcm, &(fe)->dpcm[stream].be_clients, list_be)
115 #define for_each_dpcm_be_safe(fe, stream, _dpcm, __dpcm)			\
116 	list_for_each_entry_safe(_dpcm, __dpcm, &(fe)->dpcm[stream].be_clients, list_be)
117 #define for_each_dpcm_be_rollback(fe, stream, _dpcm)			\
118 	list_for_each_entry_continue_reverse(_dpcm, &(fe)->dpcm[stream].be_clients, list_be)
119 
120 /* can this BE stop and free */
121 int snd_soc_dpcm_can_be_free_stop(struct snd_soc_pcm_runtime *fe,
122 		struct snd_soc_pcm_runtime *be, int stream);
123 
124 /* can this BE perform a hw_params() */
125 int snd_soc_dpcm_can_be_params(struct snd_soc_pcm_runtime *fe,
126 		struct snd_soc_pcm_runtime *be, int stream);
127 
128 /* is the current PCM operation for this FE ? */
129 int snd_soc_dpcm_fe_can_update(struct snd_soc_pcm_runtime *fe, int stream);
130 
131 /* is the current PCM operation for this BE ? */
132 int snd_soc_dpcm_be_can_update(struct snd_soc_pcm_runtime *fe,
133 		struct snd_soc_pcm_runtime *be, int stream);
134 
135 /* get the substream for this BE */
136 struct snd_pcm_substream *
137 	snd_soc_dpcm_get_substream(struct snd_soc_pcm_runtime *be, int stream);
138 
139 /* update audio routing between PCMs and any DAI links */
140 int snd_soc_dpcm_runtime_update(struct snd_soc_card *card);
141 
142 #ifdef CONFIG_DEBUG_FS
143 void soc_dpcm_debugfs_add(struct snd_soc_pcm_runtime *rtd);
144 #else
soc_dpcm_debugfs_add(struct snd_soc_pcm_runtime * rtd)145 static inline void soc_dpcm_debugfs_add(struct snd_soc_pcm_runtime *rtd)
146 {
147 }
148 #endif
149 
150 int dpcm_path_get(struct snd_soc_pcm_runtime *fe,
151 	int stream, struct snd_soc_dapm_widget_list **list_);
152 void dpcm_path_put(struct snd_soc_dapm_widget_list **list);
153 int dpcm_process_paths(struct snd_soc_pcm_runtime *fe,
154 	int stream, struct snd_soc_dapm_widget_list **list, int new);
155 int dpcm_be_dai_startup(struct snd_soc_pcm_runtime *fe, int stream);
156 void dpcm_be_dai_stop(struct snd_soc_pcm_runtime *fe, int stream,
157 		      int do_hw_free, struct snd_soc_dpcm *last);
158 void dpcm_be_disconnect(struct snd_soc_pcm_runtime *fe, int stream);
159 void dpcm_clear_pending_state(struct snd_soc_pcm_runtime *fe, int stream);
160 void dpcm_be_dai_hw_free(struct snd_soc_pcm_runtime *fe, int stream);
161 int dpcm_be_dai_hw_params(struct snd_soc_pcm_runtime *fe, int tream);
162 int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream, int cmd);
163 int dpcm_be_dai_prepare(struct snd_soc_pcm_runtime *fe, int stream);
164 int dpcm_dapm_stream_event(struct snd_soc_pcm_runtime *fe, int dir,
165 	int event);
166 bool dpcm_end_walk_at_be(struct snd_soc_dapm_widget *widget, enum snd_soc_dapm_direction dir);
167 
168 #define dpcm_be_dai_startup_rollback(fe, stream, last)	\
169 						dpcm_be_dai_stop(fe, stream, 0, last)
170 #define dpcm_be_dai_startup_unwind(fe, stream)	dpcm_be_dai_stop(fe, stream, 0, NULL)
171 #define dpcm_be_dai_shutdown(fe, stream)	dpcm_be_dai_stop(fe, stream, 1, NULL)
172 
173 #endif
174