sound/hda/hdac_i915.c

   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
  24 static struct i915_audio_component *hdac_acomp;
  25
  26 /**
  27  * snd_hdac_set_codec_wakeup - Enable / disable HDMI/DP codec wakeup
  28  * @bus: HDA core bus
  29  * @enable: enable or disable the wakeup
  30  *
  31  * This function is supposed to be used only by a HD-audio controller
  32  * driver that needs the interaction with i915 graphics.
  33  *
  34  * This function should be called during the chip reset, also called at
  35  * resume for updating STATESTS register read.
  36  *
  37  * Returns zero for success or a negative error code.
  38  */
  39 int snd_hdac_set_codec_wakeup(struct hdac_bus *bus, bool enable)
  40 {
  41         struct i915_audio_component *acomp = bus->audio_component;
  42
  43         if (!acomp || !acomp->ops)
  44                 return -ENODEV;
  45
  46         if (!acomp->ops->codec_wake_override) {
  47                 dev_warn(bus->dev,
  48                         "Invalid codec wake callback\n");
  49                 return 0;
  50         }
  51
  52         dev_dbg(bus->dev, "%s codec wakeup\n",
  53                 enable ? "enable" : "disable");
  54
  55         acomp->ops->codec_wake_override(acomp->dev, enable);
  56
  57         return 0;
  58 }
  59 EXPORT_SYMBOL_GPL(snd_hdac_set_codec_wakeup);
  60
  61 /**
  62  * snd_hdac_display_power - Power up / down the power refcount
  63  * @bus: HDA core bus
  64  * @enable: power up or down
  65  *
  66  * This function is supposed to be used only by a HD-audio controller
  67  * driver that needs the interaction with i915 graphics.
  68  *
  69  * This function manages a refcount and calls the i915 get_power() and
  70  * put_power() ops accordingly, toggling the codec wakeup, too.
  71  *
  72  * Returns zero for success or a negative error code.
  73  */
  74 int snd_hdac_display_power(struct hdac_bus *bus, bool enable)
  75 {
  76         struct i915_audio_component *acomp = bus->audio_component;
  77
  78         if (!acomp || !acomp->ops)
  79                 return -ENODEV;
  80
  81         dev_dbg(bus->dev, "display power %s\n",
  82                 enable ? "enable" : "disable");
  83
  84         if (enable) {
  85                 if (!bus->i915_power_refcount++) {
  86                         acomp->ops->get_power(acomp->dev);
  87                         snd_hdac_set_codec_wakeup(bus, true);
  88                         snd_hdac_set_codec_wakeup(bus, false);
  89                 }
  90         } else {
  91                 WARN_ON(!bus->i915_power_refcount);
  92                 if (!--bus->i915_power_refcount)
  93                         acomp->ops->put_power(acomp->dev);
  94         }
  95
  96         return 0;
  97 }
  98 EXPORT_SYMBOL_GPL(snd_hdac_display_power);
  99
 100 /**
 101  * snd_hdac_get_display_clk - Get CDCLK in kHz
 102  * @bus: HDA core bus
 103  *
 104  * This function is supposed to be used only by a HD-audio controller
 105  * driver that needs the interaction with i915 graphics.
 106  *
 107  * This function queries CDCLK value in kHz from the graphics driver and
 108  * returns the value.  A negative code is returned in error.
 109  */
 110 int snd_hdac_get_display_clk(struct hdac_bus *bus)
 111 {
 112         struct i915_audio_component *acomp = bus->audio_component;
 113
 114         if (!acomp || !acomp->ops)
 115                 return -ENODEV;
 116
 117         return acomp->ops->get_cdclk_freq(acomp->dev);
 118 }
 119 EXPORT_SYMBOL_GPL(snd_hdac_get_display_clk);
 120
 121 /* There is a fixed mapping between audio pin node and display port
 122  * on current Intel platforms:
 123  * Pin Widget 5 - PORT B (port = 1 in i915 driver)
 124  * Pin Widget 6 - PORT C (port = 2 in i915 driver)
 125  * Pin Widget 7 - PORT D (port = 3 in i915 driver)
 126  */
 127 static int pin2port(hda_nid_t pin_nid)
 128 {
 129         if (WARN_ON(pin_nid < 5 || pin_nid > 7))
 130                 return -1;
 131         return pin_nid - 4;
 132 }
 133
 134 /**
 135  * snd_hdac_sync_audio_rate - Set N/CTS based on the sample rate
 136  * @bus: HDA core bus
 137  * @nid: the pin widget NID
 138  * @rate: the sample rate to set
 139  *
 140  * This function is supposed to be used only by a HD-audio controller
 141  * driver that needs the interaction with i915 graphics.
 142  *
 143  * This function sets N/CTS value based on the given sample rate.
 144  * Returns zero for success, or a negative error code.
 145  */
 146 int snd_hdac_sync_audio_rate(struct hdac_bus *bus, hda_nid_t nid, int rate)
 147 {
 148         struct i915_audio_component *acomp = bus->audio_component;
 149         int port;
 150
 151         if (!acomp || !acomp->ops || !acomp->ops->sync_audio_rate)
 152                 return -ENODEV;
 153         port = pin2port(nid);
 154         if (port < 0)
 155                 return -EINVAL;
 156         return acomp->ops->sync_audio_rate(acomp->dev, port, rate);
 157 }
 158 EXPORT_SYMBOL_GPL(snd_hdac_sync_audio_rate);
 159
 160 /**
 161  * snd_hdac_acomp_get_eld - Get the audio state and ELD via component
 162  * @bus: HDA core bus
 163  * @nid: the pin widget NID
 164  * @audio_enabled: the pointer to store the current audio state
 165  * @buffer: the buffer pointer to store ELD bytes
 166  * @max_bytes: the max bytes to be stored on @buffer
 167  *
 168  * This function is supposed to be used only by a HD-audio controller
 169  * driver that needs the interaction with i915 graphics.
 170  *
 171  * This function queries the current state of the audio on the given
 172  * digital port and fetches the ELD bytes onto the given buffer.
 173  * It returns the number of bytes for the total ELD data, zero for
 174  * invalid ELD, or a negative error code.
 175  *
 176  * The return size is the total bytes required for the whole ELD bytes,
 177  * thus it may be over @max_bytes.  If it's over @max_bytes, it implies
 178  * that only a part of ELD bytes have been fetched.
 179  */
 180 int snd_hdac_acomp_get_eld(struct hdac_bus *bus, hda_nid_t nid,
 181                            bool *audio_enabled, char *buffer, int max_bytes)
 182 {
 183         struct i915_audio_component *acomp = bus->audio_component;
 184         int port;
 185
 186         if (!acomp || !acomp->ops || !acomp->ops->get_eld)
 187                 return -ENODEV;
 188
 189         port = pin2port(nid);
 190         if (port < 0)
 191                 return -EINVAL;
 192         return acomp->ops->get_eld(acomp->dev, port, audio_enabled,
 193                                    buffer, max_bytes);
 194 }
 195 EXPORT_SYMBOL_GPL(snd_hdac_acomp_get_eld);
 196
 197 static int hdac_component_master_bind(struct device *dev)
 198 {
 199         struct i915_audio_component *acomp = hdac_acomp;
 200         int ret;
 201
 202         ret = component_bind_all(dev, acomp);
 203         if (ret < 0)
 204                 return ret;
 205
 206         if (WARN_ON(!(acomp->dev && acomp->ops && acomp->ops->get_power &&
 207                       acomp->ops->put_power && acomp->ops->get_cdclk_freq))) {
 208                 ret = -EINVAL;
 209                 goto out_unbind;
 210         }
 211
 212         /*
 213          * Atm, we don't support dynamic unbinding initiated by the child
 214          * component, so pin its containing module until we unbind.
 215          */
 216         if (!try_module_get(acomp->ops->owner)) {
 217                 ret = -ENODEV;
 218                 goto out_unbind;
 219         }
 220
 221         return 0;
 222
 223 out_unbind:
 224         component_unbind_all(dev, acomp);
 225
 226         return ret;
 227 }
 228
 229 static void hdac_component_master_unbind(struct device *dev)
 230 {
 231         struct i915_audio_component *acomp = hdac_acomp;
 232
 233         module_put(acomp->ops->owner);
 234         component_unbind_all(dev, acomp);
 235         WARN_ON(acomp->ops || acomp->dev);
 236 }
 237
 238 static const struct component_master_ops hdac_component_master_ops = {
 239         .bind = hdac_component_master_bind,
 240         .unbind = hdac_component_master_unbind,
 241 };
 242
 243 static int hdac_component_master_match(struct device *dev, void *data)
 244 {
 245         /* i915 is the only supported component */
 246         return !strcmp(dev->driver->name, "i915");
 247 }
 248
 249 /**
 250  * snd_hdac_i915_register_notifier - Register i915 audio component ops
 251  * @aops: i915 audio component ops
 252  *
 253  * This function is supposed to be used only by a HD-audio controller
 254  * driver that needs the interaction with i915 graphics.
 255  *
 256  * This function sets the given ops to be called by the i915 graphics driver.
 257  *
 258  * Returns zero for success or a negative error code.
 259  */
 260 int snd_hdac_i915_register_notifier(const struct i915_audio_component_audio_ops *aops)
 261 {
 262         if (WARN_ON(!hdac_acomp))
 263                 return -ENODEV;
 264
 265         hdac_acomp->audio_ops = aops;
 266         return 0;
 267 }
 268 EXPORT_SYMBOL_GPL(snd_hdac_i915_register_notifier);
 269
 270 /* check whether intel graphics is present */
 271 static bool i915_gfx_present(void)
 272 {
 273         static struct pci_device_id ids[] = {
 274                 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_ANY_ID),
 275                   .class = PCI_BASE_CLASS_DISPLAY << 16,
 276                   .class_mask = 0xff << 16 },
 277                 {}
 278         };
 279         return pci_dev_present(ids);
 280 }
 281
 282 /**
 283  * snd_hdac_i915_init - Initialize i915 audio component
 284  * @bus: HDA core bus
 285  *
 286  * This function is supposed to be used only by a HD-audio controller
 287  * driver that needs the interaction with i915 graphics.
 288  *
 289  * This function initializes and sets up the audio component to communicate
 290  * with i915 graphics driver.
 291  *
 292  * Returns zero for success or a negative error code.
 293  */
 294 int snd_hdac_i915_init(struct hdac_bus *bus)
 295 {
 296         struct component_match *match = NULL;
 297         struct device *dev = bus->dev;
 298         struct i915_audio_component *acomp;
 299         int ret;
 300
 301         if (!i915_gfx_present())
 302                 return -ENODEV;
 303
 304         acomp = kzalloc(sizeof(*acomp), GFP_KERNEL);
 305         if (!acomp)
 306                 return -ENOMEM;
 307         bus->audio_component = acomp;
 308         hdac_acomp = acomp;
 309
 310         component_match_add(dev, &match, hdac_component_master_match, bus);
 311         ret = component_master_add_with_match(dev, &hdac_component_master_ops,
 312                                               match);
 313         if (ret < 0)
 314                 goto out_err;
 315
 316         /*
 317          * Atm, we don't support deferring the component binding, so make sure
 318          * i915 is loaded and that the binding successfully completes.
 319          */
 320         request_module("i915");
 321
 322         if (!acomp->ops) {
 323                 ret = -ENODEV;
 324                 goto out_master_del;
 325         }
 326         dev_dbg(dev, "bound to i915 component master\n");
 327
 328         return 0;
 329 out_master_del:
 330         component_master_del(dev, &hdac_component_master_ops);
 331 out_err:
 332         kfree(acomp);
 333         bus->audio_component = NULL;
 334         dev_info(dev, "failed to add i915 component master (%d)\n", ret);
 335
 336         return ret;
 337 }
 338 EXPORT_SYMBOL_GPL(snd_hdac_i915_init);
 339
 340 /**
 341  * snd_hdac_i915_exit - Finalize i915 audio component
 342  * @bus: HDA core bus
 343  *
 344  * This function is supposed to be used only by a HD-audio controller
 345  * driver that needs the interaction with i915 graphics.
 346  *
 347  * This function releases the i915 audio component that has been used.
 348  *
 349  * Returns zero for success or a negative error code.
 350  */
 351 int snd_hdac_i915_exit(struct hdac_bus *bus)
 352 {
 353         struct device *dev = bus->dev;
 354         struct i915_audio_component *acomp = bus->audio_component;
 355
 356         if (!acomp)
 357                 return 0;
 358
 359         WARN_ON(bus->i915_power_refcount);
 360         if (bus->i915_power_refcount > 0 && acomp->ops)
 361                 acomp->ops->put_power(acomp->dev);
 362
 363         component_master_del(dev, &hdac_component_master_ops);
 364
 365         kfree(acomp);
 366         bus->audio_component = NULL;
 367
 368         return 0;
 369 }
 370 EXPORT_SYMBOL_GPL(snd_hdac_i915_exit);