1 /*
2 * hdac_i915.c - routines for sync between HD-A core and i915 display driver
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by the Free
6 * Software Foundation; either version 2 of the License, or (at your option)
7 * any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
11 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * for more details.
13 */
14
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/pci.h>
18 #include <linux/component.h>
19 #include <drm/i915_component.h>
20 #include <sound/core.h>
21 #include <sound/hdaudio.h>
22 #include <sound/hda_i915.h>
23 #include <sound/hda_register.h>
24
25 static struct i915_audio_component *hdac_acomp;
26
27 /**
28 * snd_hdac_set_codec_wakeup - Enable / disable HDMI/DP codec wakeup
29 * @bus: HDA core bus
30 * @enable: enable or disable the wakeup
31 *
32 * This function is supposed to be used only by a HD-audio controller
33 * driver that needs the interaction with i915 graphics.
34 *
35 * This function should be called during the chip reset, also called at
36 * resume for updating STATESTS register read.
37 *
38 * Returns zero for success or a negative error code.
39 */
snd_hdac_set_codec_wakeup(struct hdac_bus * bus,bool enable)40 int snd_hdac_set_codec_wakeup(struct hdac_bus *bus, bool enable)
41 {
42 struct i915_audio_component *acomp = bus->audio_component;
43
44 if (!acomp || !acomp->ops)
45 return -ENODEV;
46
47 if (!acomp->ops->codec_wake_override) {
48 dev_warn(bus->dev,
49 "Invalid codec wake callback\n");
50 return 0;
51 }
52
53 dev_dbg(bus->dev, "%s codec wakeup\n",
54 enable ? "enable" : "disable");
55
56 acomp->ops->codec_wake_override(acomp->dev, enable);
57
58 return 0;
59 }
60 EXPORT_SYMBOL_GPL(snd_hdac_set_codec_wakeup);
61
62 /**
63 * snd_hdac_display_power - Power up / down the power refcount
64 * @bus: HDA core bus
65 * @enable: power up or down
66 *
67 * This function is supposed to be used only by a HD-audio controller
68 * driver that needs the interaction with i915 graphics.
69 *
70 * This function manages a refcount and calls the i915 get_power() and
71 * put_power() ops accordingly, toggling the codec wakeup, too.
72 *
73 * Returns zero for success or a negative error code.
74 */
snd_hdac_display_power(struct hdac_bus * bus,bool enable)75 int snd_hdac_display_power(struct hdac_bus *bus, bool enable)
76 {
77 struct i915_audio_component *acomp = bus->audio_component;
78
79 if (!acomp || !acomp->ops)
80 return -ENODEV;
81
82 dev_dbg(bus->dev, "display power %s\n",
83 enable ? "enable" : "disable");
84
85 if (enable) {
86 if (!bus->i915_power_refcount++) {
87 acomp->ops->get_power(acomp->dev);
88 snd_hdac_set_codec_wakeup(bus, true);
89 snd_hdac_set_codec_wakeup(bus, false);
90 }
91 } else {
92 WARN_ON(!bus->i915_power_refcount);
93 if (!--bus->i915_power_refcount)
94 acomp->ops->put_power(acomp->dev);
95 }
96
97 return 0;
98 }
99 EXPORT_SYMBOL_GPL(snd_hdac_display_power);
100
101 #define CONTROLLER_IN_GPU(pci) (((pci)->device == 0x0a0c) || \
102 ((pci)->device == 0x0c0c) || \
103 ((pci)->device == 0x0d0c) || \
104 ((pci)->device == 0x160c))
105
106 /**
107 * snd_hdac_i915_set_bclk - Reprogram BCLK for HSW/BDW
108 * @bus: HDA core bus
109 *
110 * Intel HSW/BDW display HDA controller is in GPU. Both its power and link BCLK
111 * depends on GPU. Two Extended Mode registers EM4 (M value) and EM5 (N Value)
112 * are used to convert CDClk (Core Display Clock) to 24MHz BCLK:
113 * BCLK = CDCLK * M / N
114 * The values will be lost when the display power well is disabled and need to
115 * be restored to avoid abnormal playback speed.
116 *
117 * Call this function at initializing and changing power well, as well as
118 * at ELD notifier for the hotplug.
119 */
snd_hdac_i915_set_bclk(struct hdac_bus * bus)120 void snd_hdac_i915_set_bclk(struct hdac_bus *bus)
121 {
122 struct i915_audio_component *acomp = bus->audio_component;
123 struct pci_dev *pci = to_pci_dev(bus->dev);
124 int cdclk_freq;
125 unsigned int bclk_m, bclk_n;
126
127 if (!acomp || !acomp->ops || !acomp->ops->get_cdclk_freq)
128 return; /* only for i915 binding */
129 if (!CONTROLLER_IN_GPU(pci))
130 return; /* only HSW/BDW */
131
132 cdclk_freq = acomp->ops->get_cdclk_freq(acomp->dev);
133 switch (cdclk_freq) {
134 case 337500:
135 bclk_m = 16;
136 bclk_n = 225;
137 break;
138
139 case 450000:
140 default: /* default CDCLK 450MHz */
141 bclk_m = 4;
142 bclk_n = 75;
143 break;
144
145 case 540000:
146 bclk_m = 4;
147 bclk_n = 90;
148 break;
149
150 case 675000:
151 bclk_m = 8;
152 bclk_n = 225;
153 break;
154 }
155
156 snd_hdac_chip_writew(bus, HSW_EM4, bclk_m);
157 snd_hdac_chip_writew(bus, HSW_EM5, bclk_n);
158 }
159 EXPORT_SYMBOL_GPL(snd_hdac_i915_set_bclk);
160
161 /* There is a fixed mapping between audio pin node and display port.
162 * on SNB, IVY, HSW, BSW, SKL, BXT, KBL:
163 * Pin Widget 5 - PORT B (port = 1 in i915 driver)
164 * Pin Widget 6 - PORT C (port = 2 in i915 driver)
165 * Pin Widget 7 - PORT D (port = 3 in i915 driver)
166 *
167 * on VLV, ILK:
168 * Pin Widget 4 - PORT B (port = 1 in i915 driver)
169 * Pin Widget 5 - PORT C (port = 2 in i915 driver)
170 * Pin Widget 6 - PORT D (port = 3 in i915 driver)
171 */
pin2port(struct hdac_device * codec,hda_nid_t pin_nid)172 static int pin2port(struct hdac_device *codec, hda_nid_t pin_nid)
173 {
174 int base_nid;
175
176 switch (codec->vendor_id) {
177 case 0x80860054: /* ILK */
178 case 0x80862804: /* ILK */
179 case 0x80862882: /* VLV */
180 base_nid = 3;
181 break;
182 default:
183 base_nid = 4;
184 break;
185 }
186
187 if (WARN_ON(pin_nid <= base_nid || pin_nid > base_nid + 3))
188 return -1;
189 return pin_nid - base_nid;
190 }
191
192 /**
193 * snd_hdac_sync_audio_rate - Set N/CTS based on the sample rate
194 * @codec: HDA codec
195 * @nid: the pin widget NID
196 * @rate: the sample rate to set
197 *
198 * This function is supposed to be used only by a HD-audio controller
199 * driver that needs the interaction with i915 graphics.
200 *
201 * This function sets N/CTS value based on the given sample rate.
202 * Returns zero for success, or a negative error code.
203 */
snd_hdac_sync_audio_rate(struct hdac_device * codec,hda_nid_t nid,int rate)204 int snd_hdac_sync_audio_rate(struct hdac_device *codec, hda_nid_t nid, int rate)
205 {
206 struct hdac_bus *bus = codec->bus;
207 struct i915_audio_component *acomp = bus->audio_component;
208 int port;
209
210 if (!acomp || !acomp->ops || !acomp->ops->sync_audio_rate)
211 return -ENODEV;
212 port = pin2port(codec, nid);
213 if (port < 0)
214 return -EINVAL;
215 return acomp->ops->sync_audio_rate(acomp->dev, port, rate);
216 }
217 EXPORT_SYMBOL_GPL(snd_hdac_sync_audio_rate);
218
219 /**
220 * snd_hdac_acomp_get_eld - Get the audio state and ELD via component
221 * @codec: HDA codec
222 * @nid: the pin widget NID
223 * @audio_enabled: the pointer to store the current audio state
224 * @buffer: the buffer pointer to store ELD bytes
225 * @max_bytes: the max bytes to be stored on @buffer
226 *
227 * This function is supposed to be used only by a HD-audio controller
228 * driver that needs the interaction with i915 graphics.
229 *
230 * This function queries the current state of the audio on the given
231 * digital port and fetches the ELD bytes onto the given buffer.
232 * It returns the number of bytes for the total ELD data, zero for
233 * invalid ELD, or a negative error code.
234 *
235 * The return size is the total bytes required for the whole ELD bytes,
236 * thus it may be over @max_bytes. If it's over @max_bytes, it implies
237 * that only a part of ELD bytes have been fetched.
238 */
snd_hdac_acomp_get_eld(struct hdac_device * codec,hda_nid_t nid,bool * audio_enabled,char * buffer,int max_bytes)239 int snd_hdac_acomp_get_eld(struct hdac_device *codec, hda_nid_t nid,
240 bool *audio_enabled, char *buffer, int max_bytes)
241 {
242 struct hdac_bus *bus = codec->bus;
243 struct i915_audio_component *acomp = bus->audio_component;
244 int port;
245
246 if (!acomp || !acomp->ops || !acomp->ops->get_eld)
247 return -ENODEV;
248
249 port = pin2port(codec, nid);
250 if (port < 0)
251 return -EINVAL;
252 return acomp->ops->get_eld(acomp->dev, port, audio_enabled,
253 buffer, max_bytes);
254 }
255 EXPORT_SYMBOL_GPL(snd_hdac_acomp_get_eld);
256
hdac_component_master_bind(struct device * dev)257 static int hdac_component_master_bind(struct device *dev)
258 {
259 struct i915_audio_component *acomp = hdac_acomp;
260 int ret;
261
262 ret = component_bind_all(dev, acomp);
263 if (ret < 0)
264 return ret;
265
266 if (WARN_ON(!(acomp->dev && acomp->ops && acomp->ops->get_power &&
267 acomp->ops->put_power && acomp->ops->get_cdclk_freq))) {
268 ret = -EINVAL;
269 goto out_unbind;
270 }
271
272 /*
273 * Atm, we don't support dynamic unbinding initiated by the child
274 * component, so pin its containing module until we unbind.
275 */
276 if (!try_module_get(acomp->ops->owner)) {
277 ret = -ENODEV;
278 goto out_unbind;
279 }
280
281 return 0;
282
283 out_unbind:
284 component_unbind_all(dev, acomp);
285
286 return ret;
287 }
288
hdac_component_master_unbind(struct device * dev)289 static void hdac_component_master_unbind(struct device *dev)
290 {
291 struct i915_audio_component *acomp = hdac_acomp;
292
293 module_put(acomp->ops->owner);
294 component_unbind_all(dev, acomp);
295 WARN_ON(acomp->ops || acomp->dev);
296 }
297
298 static const struct component_master_ops hdac_component_master_ops = {
299 .bind = hdac_component_master_bind,
300 .unbind = hdac_component_master_unbind,
301 };
302
hdac_component_master_match(struct device * dev,void * data)303 static int hdac_component_master_match(struct device *dev, void *data)
304 {
305 /* i915 is the only supported component */
306 return !strcmp(dev->driver->name, "i915");
307 }
308
309 /**
310 * snd_hdac_i915_register_notifier - Register i915 audio component ops
311 * @aops: i915 audio component ops
312 *
313 * This function is supposed to be used only by a HD-audio controller
314 * driver that needs the interaction with i915 graphics.
315 *
316 * This function sets the given ops to be called by the i915 graphics driver.
317 *
318 * Returns zero for success or a negative error code.
319 */
snd_hdac_i915_register_notifier(const struct i915_audio_component_audio_ops * aops)320 int snd_hdac_i915_register_notifier(const struct i915_audio_component_audio_ops *aops)
321 {
322 if (!hdac_acomp)
323 return -ENODEV;
324
325 hdac_acomp->audio_ops = aops;
326 return 0;
327 }
328 EXPORT_SYMBOL_GPL(snd_hdac_i915_register_notifier);
329
330 /* check whether intel graphics is present */
i915_gfx_present(void)331 static bool i915_gfx_present(void)
332 {
333 static struct pci_device_id ids[] = {
334 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_ANY_ID),
335 .class = PCI_BASE_CLASS_DISPLAY << 16,
336 .class_mask = 0xff << 16 },
337 {}
338 };
339 return pci_dev_present(ids);
340 }
341
342 /**
343 * snd_hdac_i915_init - Initialize i915 audio component
344 * @bus: HDA core bus
345 *
346 * This function is supposed to be used only by a HD-audio controller
347 * driver that needs the interaction with i915 graphics.
348 *
349 * This function initializes and sets up the audio component to communicate
350 * with i915 graphics driver.
351 *
352 * Returns zero for success or a negative error code.
353 */
snd_hdac_i915_init(struct hdac_bus * bus)354 int snd_hdac_i915_init(struct hdac_bus *bus)
355 {
356 struct component_match *match = NULL;
357 struct device *dev = bus->dev;
358 struct i915_audio_component *acomp;
359 int ret;
360
361 if (WARN_ON(hdac_acomp))
362 return -EBUSY;
363
364 if (!i915_gfx_present())
365 return -ENODEV;
366
367 acomp = kzalloc(sizeof(*acomp), GFP_KERNEL);
368 if (!acomp)
369 return -ENOMEM;
370 bus->audio_component = acomp;
371 hdac_acomp = acomp;
372
373 component_match_add(dev, &match, hdac_component_master_match, bus);
374 ret = component_master_add_with_match(dev, &hdac_component_master_ops,
375 match);
376 if (ret < 0)
377 goto out_err;
378
379 /*
380 * Atm, we don't support deferring the component binding, so make sure
381 * i915 is loaded and that the binding successfully completes.
382 */
383 request_module("i915");
384
385 if (!acomp->ops) {
386 ret = -ENODEV;
387 goto out_master_del;
388 }
389 dev_dbg(dev, "bound to i915 component master\n");
390
391 return 0;
392 out_master_del:
393 component_master_del(dev, &hdac_component_master_ops);
394 out_err:
395 kfree(acomp);
396 bus->audio_component = NULL;
397 hdac_acomp = NULL;
398 dev_info(dev, "failed to add i915 component master (%d)\n", ret);
399
400 return ret;
401 }
402 EXPORT_SYMBOL_GPL(snd_hdac_i915_init);
403
404 /**
405 * snd_hdac_i915_exit - Finalize i915 audio component
406 * @bus: HDA core bus
407 *
408 * This function is supposed to be used only by a HD-audio controller
409 * driver that needs the interaction with i915 graphics.
410 *
411 * This function releases the i915 audio component that has been used.
412 *
413 * Returns zero for success or a negative error code.
414 */
snd_hdac_i915_exit(struct hdac_bus * bus)415 int snd_hdac_i915_exit(struct hdac_bus *bus)
416 {
417 struct device *dev = bus->dev;
418 struct i915_audio_component *acomp = bus->audio_component;
419
420 if (!acomp)
421 return 0;
422
423 WARN_ON(bus->i915_power_refcount);
424 if (bus->i915_power_refcount > 0 && acomp->ops)
425 acomp->ops->put_power(acomp->dev);
426
427 component_master_del(dev, &hdac_component_master_ops);
428
429 kfree(acomp);
430 bus->audio_component = NULL;
431 hdac_acomp = NULL;
432
433 return 0;
434 }
435 EXPORT_SYMBOL_GPL(snd_hdac_i915_exit);
436