1 // SPDX-License-Identifier: GPL-2.0
2 // hdac_component.c - routines for sync between HD-A core and DRM driver
3 
4 #include <linux/init.h>
5 #include <linux/module.h>
6 #include <linux/pci.h>
7 #include <linux/component.h>
8 #include <sound/core.h>
9 #include <sound/hdaudio.h>
10 #include <sound/hda_component.h>
11 #include <sound/hda_register.h>
12 
hdac_acomp_release(struct device * dev,void * res)13 static void hdac_acomp_release(struct device *dev, void *res)
14 {
15 }
16 
hdac_get_acomp(struct device * dev)17 static struct drm_audio_component *hdac_get_acomp(struct device *dev)
18 {
19 	return devres_find(dev, hdac_acomp_release, NULL, NULL);
20 }
21 
22 /**
23  * snd_hdac_set_codec_wakeup - Enable / disable HDMI/DP codec wakeup
24  * @bus: HDA core bus
25  * @enable: enable or disable the wakeup
26  *
27  * This function is supposed to be used only by a HD-audio controller
28  * driver that needs the interaction with graphics driver.
29  *
30  * This function should be called during the chip reset, also called at
31  * resume for updating STATESTS register read.
32  *
33  * Returns zero for success or a negative error code.
34  */
snd_hdac_set_codec_wakeup(struct hdac_bus * bus,bool enable)35 int snd_hdac_set_codec_wakeup(struct hdac_bus *bus, bool enable)
36 {
37 	struct drm_audio_component *acomp = bus->audio_component;
38 
39 	if (!acomp || !acomp->ops)
40 		return -ENODEV;
41 
42 	if (!acomp->ops->codec_wake_override)
43 		return 0;
44 
45 	dev_dbg(bus->dev, "%s codec wakeup\n",
46 		enable ? "enable" : "disable");
47 
48 	acomp->ops->codec_wake_override(acomp->dev, enable);
49 
50 	return 0;
51 }
52 EXPORT_SYMBOL_GPL(snd_hdac_set_codec_wakeup);
53 
54 /**
55  * snd_hdac_display_power - Power up / down the power refcount
56  * @bus: HDA core bus
57  * @idx: HDA codec address, pass HDA_CODEC_IDX_CONTROLLER for controller
58  * @enable: power up or down
59  *
60  * This function is used by either HD-audio controller or codec driver that
61  * needs the interaction with graphics driver.
62  *
63  * This function updates the power status, and calls the get_power() and
64  * put_power() ops accordingly, toggling the codec wakeup, too.
65  */
snd_hdac_display_power(struct hdac_bus * bus,unsigned int idx,bool enable)66 void snd_hdac_display_power(struct hdac_bus *bus, unsigned int idx, bool enable)
67 {
68 	struct drm_audio_component *acomp = bus->audio_component;
69 
70 	dev_dbg(bus->dev, "display power %s\n",
71 		enable ? "enable" : "disable");
72 
73 	mutex_lock(&bus->lock);
74 	if (enable)
75 		set_bit(idx, &bus->display_power_status);
76 	else
77 		clear_bit(idx, &bus->display_power_status);
78 
79 	if (!acomp || !acomp->ops)
80 		goto unlock;
81 
82 	if (bus->display_power_status) {
83 		if (!bus->display_power_active) {
84 			unsigned long cookie = -1;
85 
86 			if (acomp->ops->get_power)
87 				cookie = acomp->ops->get_power(acomp->dev);
88 
89 			snd_hdac_set_codec_wakeup(bus, true);
90 			snd_hdac_set_codec_wakeup(bus, false);
91 			bus->display_power_active = cookie;
92 		}
93 	} else {
94 		if (bus->display_power_active) {
95 			unsigned long cookie = bus->display_power_active;
96 
97 			if (acomp->ops->put_power)
98 				acomp->ops->put_power(acomp->dev, cookie);
99 
100 			bus->display_power_active = 0;
101 		}
102 	}
103  unlock:
104 	mutex_unlock(&bus->lock);
105 }
106 EXPORT_SYMBOL_GPL(snd_hdac_display_power);
107 
108 /**
109  * snd_hdac_sync_audio_rate - Set N/CTS based on the sample rate
110  * @codec: HDA codec
111  * @nid: the pin widget NID
112  * @dev_id: device identifier
113  * @rate: the sample rate to set
114  *
115  * This function is supposed to be used only by a HD-audio controller
116  * driver that needs the interaction with graphics driver.
117  *
118  * This function sets N/CTS value based on the given sample rate.
119  * Returns zero for success, or a negative error code.
120  */
snd_hdac_sync_audio_rate(struct hdac_device * codec,hda_nid_t nid,int dev_id,int rate)121 int snd_hdac_sync_audio_rate(struct hdac_device *codec, hda_nid_t nid,
122 			     int dev_id, int rate)
123 {
124 	struct hdac_bus *bus = codec->bus;
125 	struct drm_audio_component *acomp = bus->audio_component;
126 	int port, pipe;
127 
128 	if (!acomp || !acomp->ops || !acomp->ops->sync_audio_rate)
129 		return -ENODEV;
130 	port = nid;
131 	if (acomp->audio_ops && acomp->audio_ops->pin2port) {
132 		port = acomp->audio_ops->pin2port(codec, nid);
133 		if (port < 0)
134 			return -EINVAL;
135 	}
136 	pipe = dev_id;
137 	return acomp->ops->sync_audio_rate(acomp->dev, port, pipe, rate);
138 }
139 EXPORT_SYMBOL_GPL(snd_hdac_sync_audio_rate);
140 
141 /**
142  * snd_hdac_acomp_get_eld - Get the audio state and ELD via component
143  * @codec: HDA codec
144  * @nid: the pin widget NID
145  * @dev_id: device identifier
146  * @audio_enabled: the pointer to store the current audio state
147  * @buffer: the buffer pointer to store ELD bytes
148  * @max_bytes: the max bytes to be stored on @buffer
149  *
150  * This function is supposed to be used only by a HD-audio controller
151  * driver that needs the interaction with graphics driver.
152  *
153  * This function queries the current state of the audio on the given
154  * digital port and fetches the ELD bytes onto the given buffer.
155  * It returns the number of bytes for the total ELD data, zero for
156  * invalid ELD, or a negative error code.
157  *
158  * The return size is the total bytes required for the whole ELD bytes,
159  * thus it may be over @max_bytes.  If it's over @max_bytes, it implies
160  * that only a part of ELD bytes have been fetched.
161  */
snd_hdac_acomp_get_eld(struct hdac_device * codec,hda_nid_t nid,int dev_id,bool * audio_enabled,char * buffer,int max_bytes)162 int snd_hdac_acomp_get_eld(struct hdac_device *codec, hda_nid_t nid, int dev_id,
163 			   bool *audio_enabled, char *buffer, int max_bytes)
164 {
165 	struct hdac_bus *bus = codec->bus;
166 	struct drm_audio_component *acomp = bus->audio_component;
167 	int port, pipe;
168 
169 	if (!acomp || !acomp->ops || !acomp->ops->get_eld)
170 		return -ENODEV;
171 
172 	port = nid;
173 	if (acomp->audio_ops && acomp->audio_ops->pin2port) {
174 		port = acomp->audio_ops->pin2port(codec, nid);
175 		if (port < 0)
176 			return -EINVAL;
177 	}
178 	pipe = dev_id;
179 	return acomp->ops->get_eld(acomp->dev, port, pipe, audio_enabled,
180 				   buffer, max_bytes);
181 }
182 EXPORT_SYMBOL_GPL(snd_hdac_acomp_get_eld);
183 
hdac_component_master_bind(struct device * dev)184 static int hdac_component_master_bind(struct device *dev)
185 {
186 	struct drm_audio_component *acomp = hdac_get_acomp(dev);
187 	int ret;
188 
189 	if (WARN_ON(!acomp))
190 		return -EINVAL;
191 
192 	ret = component_bind_all(dev, acomp);
193 	if (ret < 0)
194 		return ret;
195 
196 	if (WARN_ON(!(acomp->dev && acomp->ops))) {
197 		ret = -EINVAL;
198 		goto out_unbind;
199 	}
200 
201 	/* pin the module to avoid dynamic unbinding, but only if given */
202 	if (!try_module_get(acomp->ops->owner)) {
203 		ret = -ENODEV;
204 		goto out_unbind;
205 	}
206 
207 	if (acomp->audio_ops && acomp->audio_ops->master_bind) {
208 		ret = acomp->audio_ops->master_bind(dev, acomp);
209 		if (ret < 0)
210 			goto module_put;
211 	}
212 
213 	complete_all(&acomp->master_bind_complete);
214 	return 0;
215 
216  module_put:
217 	module_put(acomp->ops->owner);
218 out_unbind:
219 	component_unbind_all(dev, acomp);
220 	complete_all(&acomp->master_bind_complete);
221 
222 	return ret;
223 }
224 
hdac_component_master_unbind(struct device * dev)225 static void hdac_component_master_unbind(struct device *dev)
226 {
227 	struct drm_audio_component *acomp = hdac_get_acomp(dev);
228 
229 	if (acomp->audio_ops && acomp->audio_ops->master_unbind)
230 		acomp->audio_ops->master_unbind(dev, acomp);
231 	module_put(acomp->ops->owner);
232 	component_unbind_all(dev, acomp);
233 	WARN_ON(acomp->ops || acomp->dev);
234 }
235 
236 static const struct component_master_ops hdac_component_master_ops = {
237 	.bind = hdac_component_master_bind,
238 	.unbind = hdac_component_master_unbind,
239 };
240 
241 /**
242  * snd_hdac_acomp_register_notifier - Register audio component ops
243  * @bus: HDA core bus
244  * @aops: audio component ops
245  *
246  * This function is supposed to be used only by a HD-audio controller
247  * driver that needs the interaction with graphics driver.
248  *
249  * This function sets the given ops to be called by the graphics driver.
250  *
251  * Returns zero for success or a negative error code.
252  */
snd_hdac_acomp_register_notifier(struct hdac_bus * bus,const struct drm_audio_component_audio_ops * aops)253 int snd_hdac_acomp_register_notifier(struct hdac_bus *bus,
254 				    const struct drm_audio_component_audio_ops *aops)
255 {
256 	if (!bus->audio_component)
257 		return -ENODEV;
258 
259 	bus->audio_component->audio_ops = aops;
260 	return 0;
261 }
262 EXPORT_SYMBOL_GPL(snd_hdac_acomp_register_notifier);
263 
264 /**
265  * snd_hdac_acomp_init - Initialize audio component
266  * @bus: HDA core bus
267  * @aops: audio component ops
268  * @match_master: match function for finding components
269  * @extra_size: Extra bytes to allocate
270  *
271  * This function is supposed to be used only by a HD-audio controller
272  * driver that needs the interaction with graphics driver.
273  *
274  * This function initializes and sets up the audio component to communicate
275  * with graphics driver.
276  *
277  * Unlike snd_hdac_i915_init(), this function doesn't synchronize with the
278  * binding with the DRM component.  Each caller needs to sync via master_bind
279  * audio_ops.
280  *
281  * Returns zero for success or a negative error code.
282  */
snd_hdac_acomp_init(struct hdac_bus * bus,const struct drm_audio_component_audio_ops * aops,int (* match_master)(struct device *,int,void *),size_t extra_size)283 int snd_hdac_acomp_init(struct hdac_bus *bus,
284 			const struct drm_audio_component_audio_ops *aops,
285 			int (*match_master)(struct device *, int, void *),
286 			size_t extra_size)
287 {
288 	struct component_match *match = NULL;
289 	struct device *dev = bus->dev;
290 	struct drm_audio_component *acomp;
291 	int ret;
292 
293 	if (WARN_ON(hdac_get_acomp(dev)))
294 		return -EBUSY;
295 
296 	acomp = devres_alloc(hdac_acomp_release, sizeof(*acomp) + extra_size,
297 			     GFP_KERNEL);
298 	if (!acomp)
299 		return -ENOMEM;
300 	acomp->audio_ops = aops;
301 	init_completion(&acomp->master_bind_complete);
302 	bus->audio_component = acomp;
303 	devres_add(dev, acomp);
304 
305 	component_match_add_typed(dev, &match, match_master, bus);
306 	ret = component_master_add_with_match(dev, &hdac_component_master_ops,
307 					      match);
308 	if (ret < 0)
309 		goto out_err;
310 
311 	return 0;
312 
313 out_err:
314 	bus->audio_component = NULL;
315 	devres_destroy(dev, hdac_acomp_release, NULL, NULL);
316 	dev_info(dev, "failed to add audio component master (%d)\n", ret);
317 
318 	return ret;
319 }
320 EXPORT_SYMBOL_GPL(snd_hdac_acomp_init);
321 
322 /**
323  * snd_hdac_acomp_exit - Finalize audio component
324  * @bus: HDA core bus
325  *
326  * This function is supposed to be used only by a HD-audio controller
327  * driver that needs the interaction with graphics driver.
328  *
329  * This function releases the audio component that has been used.
330  *
331  * Returns zero for success or a negative error code.
332  */
snd_hdac_acomp_exit(struct hdac_bus * bus)333 int snd_hdac_acomp_exit(struct hdac_bus *bus)
334 {
335 	struct device *dev = bus->dev;
336 	struct drm_audio_component *acomp = bus->audio_component;
337 
338 	if (!acomp)
339 		return 0;
340 
341 	if (WARN_ON(bus->display_power_active) && acomp->ops)
342 		acomp->ops->put_power(acomp->dev, bus->display_power_active);
343 
344 	bus->display_power_active = 0;
345 	bus->display_power_status = 0;
346 
347 	component_master_del(dev, &hdac_component_master_ops);
348 
349 	bus->audio_component = NULL;
350 	devres_destroy(dev, hdac_acomp_release, NULL, NULL);
351 
352 	return 0;
353 }
354 EXPORT_SYMBOL_GPL(snd_hdac_acomp_exit);
355