1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * media.c - Media Controller specific ALSA driver code |
4 | * |
5 | * Copyright (c) 2019 Shuah Khan <shuah@kernel.org> |
6 | * |
7 | */ |
8 | |
9 | /* |
10 | * This file adds Media Controller support to the ALSA driver |
11 | * to use the Media Controller API to share the tuner with DVB |
12 | * and V4L2 drivers that control the media device. |
13 | * |
14 | * The media device is created based on the existing quirks framework. |
15 | * Using this approach, the media controller API usage can be added for |
16 | * a specific device. |
17 | */ |
18 | |
19 | #include <linux/init.h> |
20 | #include <linux/list.h> |
21 | #include <linux/mutex.h> |
22 | #include <linux/slab.h> |
23 | #include <linux/usb.h> |
24 | |
25 | #include <sound/pcm.h> |
26 | #include <sound/core.h> |
27 | |
28 | #include "usbaudio.h" |
29 | #include "card.h" |
30 | #include "mixer.h" |
31 | #include "media.h" |
32 | |
33 | int snd_media_stream_init(struct snd_usb_substream *subs, struct snd_pcm *pcm, |
34 | int stream) |
35 | { |
36 | struct media_device *mdev; |
37 | struct media_ctl *mctl; |
38 | struct device *pcm_dev = pcm->streams[stream].dev; |
39 | u32 intf_type; |
40 | int ret = 0; |
41 | u16 mixer_pad; |
42 | struct media_entity *entity; |
43 | |
44 | mdev = subs->stream->chip->media_dev; |
45 | if (!mdev) |
46 | return 0; |
47 | |
48 | if (subs->media_ctl) |
49 | return 0; |
50 | |
51 | /* allocate media_ctl */ |
52 | mctl = kzalloc(size: sizeof(*mctl), GFP_KERNEL); |
53 | if (!mctl) |
54 | return -ENOMEM; |
55 | |
56 | mctl->media_dev = mdev; |
57 | if (stream == SNDRV_PCM_STREAM_PLAYBACK) { |
58 | intf_type = MEDIA_INTF_T_ALSA_PCM_PLAYBACK; |
59 | mctl->media_entity.function = MEDIA_ENT_F_AUDIO_PLAYBACK; |
60 | mctl->media_pad.flags = MEDIA_PAD_FL_SOURCE; |
61 | mixer_pad = 1; |
62 | } else { |
63 | intf_type = MEDIA_INTF_T_ALSA_PCM_CAPTURE; |
64 | mctl->media_entity.function = MEDIA_ENT_F_AUDIO_CAPTURE; |
65 | mctl->media_pad.flags = MEDIA_PAD_FL_SINK; |
66 | mixer_pad = 2; |
67 | } |
68 | mctl->media_entity.name = pcm->name; |
69 | media_entity_pads_init(entity: &mctl->media_entity, num_pads: 1, pads: &mctl->media_pad); |
70 | ret = media_device_register_entity(mdev: mctl->media_dev, |
71 | entity: &mctl->media_entity); |
72 | if (ret) |
73 | goto free_mctl; |
74 | |
75 | mctl->intf_devnode = media_devnode_create(mdev, type: intf_type, flags: 0, |
76 | MAJOR(pcm_dev->devt), |
77 | MINOR(pcm_dev->devt)); |
78 | if (!mctl->intf_devnode) { |
79 | ret = -ENOMEM; |
80 | goto unregister_entity; |
81 | } |
82 | mctl->intf_link = media_create_intf_link(entity: &mctl->media_entity, |
83 | intf: &mctl->intf_devnode->intf, |
84 | MEDIA_LNK_FL_ENABLED); |
85 | if (!mctl->intf_link) { |
86 | ret = -ENOMEM; |
87 | goto devnode_remove; |
88 | } |
89 | |
90 | /* create link between mixer and audio */ |
91 | media_device_for_each_entity(entity, mdev) { |
92 | switch (entity->function) { |
93 | case MEDIA_ENT_F_AUDIO_MIXER: |
94 | ret = media_create_pad_link(source: entity, source_pad: mixer_pad, |
95 | sink: &mctl->media_entity, sink_pad: 0, |
96 | MEDIA_LNK_FL_ENABLED); |
97 | if (ret) |
98 | goto remove_intf_link; |
99 | break; |
100 | } |
101 | } |
102 | |
103 | subs->media_ctl = mctl; |
104 | return 0; |
105 | |
106 | remove_intf_link: |
107 | media_remove_intf_link(link: mctl->intf_link); |
108 | devnode_remove: |
109 | media_devnode_remove(devnode: mctl->intf_devnode); |
110 | unregister_entity: |
111 | media_device_unregister_entity(entity: &mctl->media_entity); |
112 | free_mctl: |
113 | kfree(objp: mctl); |
114 | return ret; |
115 | } |
116 | |
117 | void snd_media_stream_delete(struct snd_usb_substream *subs) |
118 | { |
119 | struct media_ctl *mctl = subs->media_ctl; |
120 | |
121 | if (mctl) { |
122 | struct media_device *mdev; |
123 | |
124 | mdev = mctl->media_dev; |
125 | if (mdev && media_devnode_is_registered(devnode: mdev->devnode)) { |
126 | media_devnode_remove(devnode: mctl->intf_devnode); |
127 | media_device_unregister_entity(entity: &mctl->media_entity); |
128 | media_entity_cleanup(entity: &mctl->media_entity); |
129 | } |
130 | kfree(objp: mctl); |
131 | subs->media_ctl = NULL; |
132 | } |
133 | } |
134 | |
135 | int snd_media_start_pipeline(struct snd_usb_substream *subs) |
136 | { |
137 | struct media_ctl *mctl = subs->media_ctl; |
138 | int ret = 0; |
139 | |
140 | if (!mctl) |
141 | return 0; |
142 | |
143 | mutex_lock(&mctl->media_dev->graph_mutex); |
144 | if (mctl->media_dev->enable_source) |
145 | ret = mctl->media_dev->enable_source(&mctl->media_entity, |
146 | &mctl->media_pipe); |
147 | mutex_unlock(lock: &mctl->media_dev->graph_mutex); |
148 | return ret; |
149 | } |
150 | |
151 | void snd_media_stop_pipeline(struct snd_usb_substream *subs) |
152 | { |
153 | struct media_ctl *mctl = subs->media_ctl; |
154 | |
155 | if (!mctl) |
156 | return; |
157 | |
158 | mutex_lock(&mctl->media_dev->graph_mutex); |
159 | if (mctl->media_dev->disable_source) |
160 | mctl->media_dev->disable_source(&mctl->media_entity); |
161 | mutex_unlock(lock: &mctl->media_dev->graph_mutex); |
162 | } |
163 | |
164 | static int snd_media_mixer_init(struct snd_usb_audio *chip) |
165 | { |
166 | struct device *ctl_dev = chip->card->ctl_dev; |
167 | struct media_intf_devnode *ctl_intf; |
168 | struct usb_mixer_interface *mixer; |
169 | struct media_device *mdev = chip->media_dev; |
170 | struct media_mixer_ctl *mctl; |
171 | u32 intf_type = MEDIA_INTF_T_ALSA_CONTROL; |
172 | int ret; |
173 | |
174 | if (!mdev) |
175 | return -ENODEV; |
176 | |
177 | ctl_intf = chip->ctl_intf_media_devnode; |
178 | if (!ctl_intf) { |
179 | ctl_intf = media_devnode_create(mdev, type: intf_type, flags: 0, |
180 | MAJOR(ctl_dev->devt), |
181 | MINOR(ctl_dev->devt)); |
182 | if (!ctl_intf) |
183 | return -ENOMEM; |
184 | chip->ctl_intf_media_devnode = ctl_intf; |
185 | } |
186 | |
187 | list_for_each_entry(mixer, &chip->mixer_list, list) { |
188 | |
189 | if (mixer->media_mixer_ctl) |
190 | continue; |
191 | |
192 | /* allocate media_mixer_ctl */ |
193 | mctl = kzalloc(size: sizeof(*mctl), GFP_KERNEL); |
194 | if (!mctl) |
195 | return -ENOMEM; |
196 | |
197 | mctl->media_dev = mdev; |
198 | mctl->media_entity.function = MEDIA_ENT_F_AUDIO_MIXER; |
199 | mctl->media_entity.name = chip->card->mixername; |
200 | mctl->media_pad[0].flags = MEDIA_PAD_FL_SINK; |
201 | mctl->media_pad[1].flags = MEDIA_PAD_FL_SOURCE; |
202 | mctl->media_pad[2].flags = MEDIA_PAD_FL_SOURCE; |
203 | media_entity_pads_init(entity: &mctl->media_entity, MEDIA_MIXER_PAD_MAX, |
204 | pads: mctl->media_pad); |
205 | ret = media_device_register_entity(mdev: mctl->media_dev, |
206 | entity: &mctl->media_entity); |
207 | if (ret) { |
208 | kfree(objp: mctl); |
209 | return ret; |
210 | } |
211 | |
212 | mctl->intf_link = media_create_intf_link(entity: &mctl->media_entity, |
213 | intf: &ctl_intf->intf, |
214 | MEDIA_LNK_FL_ENABLED); |
215 | if (!mctl->intf_link) { |
216 | media_device_unregister_entity(entity: &mctl->media_entity); |
217 | media_entity_cleanup(entity: &mctl->media_entity); |
218 | kfree(objp: mctl); |
219 | return -ENOMEM; |
220 | } |
221 | mctl->intf_devnode = ctl_intf; |
222 | mixer->media_mixer_ctl = mctl; |
223 | } |
224 | return 0; |
225 | } |
226 | |
227 | static void snd_media_mixer_delete(struct snd_usb_audio *chip) |
228 | { |
229 | struct usb_mixer_interface *mixer; |
230 | struct media_device *mdev = chip->media_dev; |
231 | |
232 | if (!mdev) |
233 | return; |
234 | |
235 | list_for_each_entry(mixer, &chip->mixer_list, list) { |
236 | struct media_mixer_ctl *mctl; |
237 | |
238 | mctl = mixer->media_mixer_ctl; |
239 | if (!mixer->media_mixer_ctl) |
240 | continue; |
241 | |
242 | if (media_devnode_is_registered(devnode: mdev->devnode)) { |
243 | media_device_unregister_entity(entity: &mctl->media_entity); |
244 | media_entity_cleanup(entity: &mctl->media_entity); |
245 | } |
246 | kfree(objp: mctl); |
247 | mixer->media_mixer_ctl = NULL; |
248 | } |
249 | if (media_devnode_is_registered(devnode: mdev->devnode)) |
250 | media_devnode_remove(devnode: chip->ctl_intf_media_devnode); |
251 | chip->ctl_intf_media_devnode = NULL; |
252 | } |
253 | |
254 | int snd_media_device_create(struct snd_usb_audio *chip, |
255 | struct usb_interface *iface) |
256 | { |
257 | struct media_device *mdev; |
258 | struct usb_device *usbdev = interface_to_usbdev(iface); |
259 | int ret = 0; |
260 | |
261 | /* usb-audio driver is probed for each usb interface, and |
262 | * there are multiple interfaces per device. Avoid calling |
263 | * media_device_usb_allocate() each time usb_audio_probe() |
264 | * is called. Do it only once. |
265 | */ |
266 | if (chip->media_dev) { |
267 | mdev = chip->media_dev; |
268 | goto snd_mixer_init; |
269 | } |
270 | |
271 | mdev = media_device_usb_allocate(udev: usbdev, KBUILD_MODNAME, THIS_MODULE); |
272 | if (IS_ERR(ptr: mdev)) |
273 | return -ENOMEM; |
274 | |
275 | /* save media device - avoid lookups */ |
276 | chip->media_dev = mdev; |
277 | |
278 | snd_mixer_init: |
279 | /* Create media entities for mixer and control dev */ |
280 | ret = snd_media_mixer_init(chip); |
281 | /* media_device might be registered, print error and continue */ |
282 | if (ret) |
283 | dev_err(&usbdev->dev, |
284 | "Couldn't create media mixer entities. Error: %d\n" , |
285 | ret); |
286 | |
287 | if (!media_devnode_is_registered(devnode: mdev->devnode)) { |
288 | /* don't register if snd_media_mixer_init() failed */ |
289 | if (ret) |
290 | goto create_fail; |
291 | |
292 | /* register media_device */ |
293 | ret = media_device_register(mdev); |
294 | create_fail: |
295 | if (ret) { |
296 | snd_media_mixer_delete(chip); |
297 | media_device_delete(mdev, KBUILD_MODNAME, THIS_MODULE); |
298 | /* clear saved media_dev */ |
299 | chip->media_dev = NULL; |
300 | dev_err(&usbdev->dev, |
301 | "Couldn't register media device. Error: %d\n" , |
302 | ret); |
303 | return ret; |
304 | } |
305 | } |
306 | |
307 | return ret; |
308 | } |
309 | |
310 | void snd_media_device_delete(struct snd_usb_audio *chip) |
311 | { |
312 | struct media_device *mdev = chip->media_dev; |
313 | struct snd_usb_stream *stream; |
314 | |
315 | /* release resources */ |
316 | list_for_each_entry(stream, &chip->pcm_list, list) { |
317 | snd_media_stream_delete(subs: &stream->substream[0]); |
318 | snd_media_stream_delete(subs: &stream->substream[1]); |
319 | } |
320 | |
321 | snd_media_mixer_delete(chip); |
322 | |
323 | if (mdev) { |
324 | media_device_delete(mdev, KBUILD_MODNAME, THIS_MODULE); |
325 | chip->media_dev = NULL; |
326 | } |
327 | } |
328 | |