2 * hdac_i915.c - routines for sync between HD-A core and i915 display driver
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)
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
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>
25 static struct i915_audio_component *hdac_acomp;
28 * snd_hdac_set_codec_wakeup - Enable / disable HDMI/DP codec wakeup
30 * @enable: enable or disable the wakeup
32 * This function is supposed to be used only by a HD-audio controller
33 * driver that needs the interaction with i915 graphics.
35 * This function should be called during the chip reset, also called at
36 * resume for updating STATESTS register read.
38 * Returns zero for success or a negative error code.
40 int snd_hdac_set_codec_wakeup(struct hdac_bus *bus, bool enable)
42 struct i915_audio_component *acomp = bus->audio_component;
44 if (!acomp || !acomp->ops)
47 if (!acomp->ops->codec_wake_override) {
49 "Invalid codec wake callback\n");
53 dev_dbg(bus->dev, "%s codec wakeup\n",
54 enable ? "enable" : "disable");
56 acomp->ops->codec_wake_override(acomp->dev, enable);
60 EXPORT_SYMBOL_GPL(snd_hdac_set_codec_wakeup);
63 * snd_hdac_display_power - Power up / down the power refcount
65 * @enable: power up or down
67 * This function is supposed to be used only by a HD-audio controller
68 * driver that needs the interaction with i915 graphics.
70 * This function manages a refcount and calls the i915 get_power() and
71 * put_power() ops accordingly, toggling the codec wakeup, too.
73 * Returns zero for success or a negative error code.
75 int snd_hdac_display_power(struct hdac_bus *bus, bool enable)
77 struct i915_audio_component *acomp = bus->audio_component;
79 if (!acomp || !acomp->ops)
82 dev_dbg(bus->dev, "display power %s\n",
83 enable ? "enable" : "disable");
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);
92 WARN_ON(!bus->i915_power_refcount);
93 if (!--bus->i915_power_refcount)
94 acomp->ops->put_power(acomp->dev);
99 EXPORT_SYMBOL_GPL(snd_hdac_display_power);
101 #define CONTROLLER_IN_GPU(pci) (((pci)->device == 0x0a0c) || \
102 ((pci)->device == 0x0c0c) || \
103 ((pci)->device == 0x0d0c) || \
104 ((pci)->device == 0x160c))
107 * snd_hdac_i915_set_bclk - Reprogram BCLK for HSW/BDW
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.
117 * Call this function at initializing and changing power well, as well as
118 * at ELD notifier for the hotplug.
120 void snd_hdac_i915_set_bclk(struct hdac_bus *bus)
122 struct i915_audio_component *acomp = bus->audio_component;
123 struct pci_dev *pci = to_pci_dev(bus->dev);
125 unsigned int bclk_m, bclk_n;
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 */
132 cdclk_freq = acomp->ops->get_cdclk_freq(acomp->dev);
133 switch (cdclk_freq) {
140 default: /* default CDCLK 450MHz */
156 snd_hdac_chip_writew(bus, HSW_EM4, bclk_m);
157 snd_hdac_chip_writew(bus, HSW_EM5, bclk_n);
159 EXPORT_SYMBOL_GPL(snd_hdac_i915_set_bclk);
161 /* There is a fixed mapping between audio pin node and display port
162 * on current Intel platforms:
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)
167 static int pin2port(hda_nid_t pin_nid)
169 if (WARN_ON(pin_nid < 5 || pin_nid > 7))
175 * snd_hdac_sync_audio_rate - Set N/CTS based on the sample rate
177 * @nid: the pin widget NID
178 * @rate: the sample rate to set
180 * This function is supposed to be used only by a HD-audio controller
181 * driver that needs the interaction with i915 graphics.
183 * This function sets N/CTS value based on the given sample rate.
184 * Returns zero for success, or a negative error code.
186 int snd_hdac_sync_audio_rate(struct hdac_bus *bus, hda_nid_t nid, int rate)
188 struct i915_audio_component *acomp = bus->audio_component;
191 if (!acomp || !acomp->ops || !acomp->ops->sync_audio_rate)
193 port = pin2port(nid);
196 return acomp->ops->sync_audio_rate(acomp->dev, port, rate);
198 EXPORT_SYMBOL_GPL(snd_hdac_sync_audio_rate);
201 * snd_hdac_acomp_get_eld - Get the audio state and ELD via component
203 * @nid: the pin widget NID
204 * @audio_enabled: the pointer to store the current audio state
205 * @buffer: the buffer pointer to store ELD bytes
206 * @max_bytes: the max bytes to be stored on @buffer
208 * This function is supposed to be used only by a HD-audio controller
209 * driver that needs the interaction with i915 graphics.
211 * This function queries the current state of the audio on the given
212 * digital port and fetches the ELD bytes onto the given buffer.
213 * It returns the number of bytes for the total ELD data, zero for
214 * invalid ELD, or a negative error code.
216 * The return size is the total bytes required for the whole ELD bytes,
217 * thus it may be over @max_bytes. If it's over @max_bytes, it implies
218 * that only a part of ELD bytes have been fetched.
220 int snd_hdac_acomp_get_eld(struct hdac_bus *bus, hda_nid_t nid,
221 bool *audio_enabled, char *buffer, int max_bytes)
223 struct i915_audio_component *acomp = bus->audio_component;
226 if (!acomp || !acomp->ops || !acomp->ops->get_eld)
229 port = pin2port(nid);
232 return acomp->ops->get_eld(acomp->dev, port, audio_enabled,
235 EXPORT_SYMBOL_GPL(snd_hdac_acomp_get_eld);
237 static int hdac_component_master_bind(struct device *dev)
239 struct i915_audio_component *acomp = hdac_acomp;
242 ret = component_bind_all(dev, acomp);
246 if (WARN_ON(!(acomp->dev && acomp->ops && acomp->ops->get_power &&
247 acomp->ops->put_power && acomp->ops->get_cdclk_freq))) {
253 * Atm, we don't support dynamic unbinding initiated by the child
254 * component, so pin its containing module until we unbind.
256 if (!try_module_get(acomp->ops->owner)) {
264 component_unbind_all(dev, acomp);
269 static void hdac_component_master_unbind(struct device *dev)
271 struct i915_audio_component *acomp = hdac_acomp;
273 module_put(acomp->ops->owner);
274 component_unbind_all(dev, acomp);
275 WARN_ON(acomp->ops || acomp->dev);
278 static const struct component_master_ops hdac_component_master_ops = {
279 .bind = hdac_component_master_bind,
280 .unbind = hdac_component_master_unbind,
283 static int hdac_component_master_match(struct device *dev, void *data)
285 /* i915 is the only supported component */
286 return !strcmp(dev->driver->name, "i915");
290 * snd_hdac_i915_register_notifier - Register i915 audio component ops
291 * @aops: i915 audio component ops
293 * This function is supposed to be used only by a HD-audio controller
294 * driver that needs the interaction with i915 graphics.
296 * This function sets the given ops to be called by the i915 graphics driver.
298 * Returns zero for success or a negative error code.
300 int snd_hdac_i915_register_notifier(const struct i915_audio_component_audio_ops *aops)
302 if (WARN_ON(!hdac_acomp))
305 hdac_acomp->audio_ops = aops;
308 EXPORT_SYMBOL_GPL(snd_hdac_i915_register_notifier);
310 /* check whether intel graphics is present */
311 static bool i915_gfx_present(void)
313 static struct pci_device_id ids[] = {
314 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_ANY_ID),
315 .class = PCI_BASE_CLASS_DISPLAY << 16,
316 .class_mask = 0xff << 16 },
319 return pci_dev_present(ids);
323 * snd_hdac_i915_init - Initialize i915 audio component
326 * This function is supposed to be used only by a HD-audio controller
327 * driver that needs the interaction with i915 graphics.
329 * This function initializes and sets up the audio component to communicate
330 * with i915 graphics driver.
332 * Returns zero for success or a negative error code.
334 int snd_hdac_i915_init(struct hdac_bus *bus)
336 struct component_match *match = NULL;
337 struct device *dev = bus->dev;
338 struct i915_audio_component *acomp;
341 if (!i915_gfx_present())
344 acomp = kzalloc(sizeof(*acomp), GFP_KERNEL);
347 bus->audio_component = acomp;
350 component_match_add(dev, &match, hdac_component_master_match, bus);
351 ret = component_master_add_with_match(dev, &hdac_component_master_ops,
357 * Atm, we don't support deferring the component binding, so make sure
358 * i915 is loaded and that the binding successfully completes.
360 request_module("i915");
366 dev_dbg(dev, "bound to i915 component master\n");
370 component_master_del(dev, &hdac_component_master_ops);
373 bus->audio_component = NULL;
374 dev_info(dev, "failed to add i915 component master (%d)\n", ret);
378 EXPORT_SYMBOL_GPL(snd_hdac_i915_init);
381 * snd_hdac_i915_exit - Finalize i915 audio component
384 * This function is supposed to be used only by a HD-audio controller
385 * driver that needs the interaction with i915 graphics.
387 * This function releases the i915 audio component that has been used.
389 * Returns zero for success or a negative error code.
391 int snd_hdac_i915_exit(struct hdac_bus *bus)
393 struct device *dev = bus->dev;
394 struct i915_audio_component *acomp = bus->audio_component;
399 WARN_ON(bus->i915_power_refcount);
400 if (bus->i915_power_refcount > 0 && acomp->ops)
401 acomp->ops->put_power(acomp->dev);
403 component_master_del(dev, &hdac_component_master_ops);
406 bus->audio_component = NULL;
410 EXPORT_SYMBOL_GPL(snd_hdac_i915_exit);