drivers/gpu/drm/i915/intel_lpe_audio.c

   1 /*
   2  * Copyright © 2016 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *    Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
  25  *    Jerome Anand <jerome.anand@intel.com>
  26  *    based on VED patches
  27  *
  28  */
  29
  30 /**
  31  * DOC: LPE Audio integration for HDMI or DP playback
  32  *
  33  * Motivation:
  34  * Atom platforms (e.g. valleyview and cherryTrail) integrates a DMA-based
  35  * interface as an alternative to the traditional HDaudio path. While this
  36  * mode is unrelated to the LPE aka SST audio engine, the documentation refers
  37  * to this mode as LPE so we keep this notation for the sake of consistency.
  38  *
  39  * The interface is handled by a separate standalone driver maintained in the
  40  * ALSA subsystem for simplicity. To minimize the interaction between the two
  41  * subsystems, a bridge is setup between the hdmi-lpe-audio and i915:
  42  * 1. Create a platform device to share MMIO/IRQ resources
  43  * 2. Make the platform device child of i915 device for runtime PM.
  44  * 3. Create IRQ chip to forward the LPE audio irqs.
  45  * the hdmi-lpe-audio driver probes the lpe audio device and creates a new
  46  * sound card
  47  *
  48  * Threats:
  49  * Due to the restriction in Linux platform device model, user need manually
  50  * uninstall the hdmi-lpe-audio driver before uninstalling i915 module,
  51  * otherwise we might run into use-after-free issues after i915 removes the
  52  * platform device: even though hdmi-lpe-audio driver is released, the modules
  53  * is still in "installed" status.
  54  *
  55  * Implementation:
  56  * The MMIO/REG platform resources are created according to the registers
  57  * specification.
  58  * When forwarding LPE audio irqs, the flow control handler selection depends
  59  * on the platform, for example on valleyview handle_simple_irq is enough.
  60  *
  61  */
  62
  63 #include <linux/acpi.h>
  64 #include <linux/device.h>
  65 #include <linux/irq.h>
  66 #include <linux/pci.h>
  67 #include <linux/pm_runtime.h>
  68
  69 #include "i915_drv.h"
  70 #include <linux/delay.h>
  71 #include <drm/intel_lpe_audio.h>
  72
  73 #define HAS_LPE_AUDIO(dev_priv) ((dev_priv)->lpe_audio.platdev != NULL)
  74
  75 static struct platform_device *
  76 lpe_audio_platdev_create(struct drm_i915_private *dev_priv)
  77 {
  78         int ret;
  79         struct drm_device *dev = &dev_priv->drm;
  80         struct platform_device_info pinfo = {};
  81         struct resource *rsc;
  82         struct platform_device *platdev;
  83         struct intel_hdmi_lpe_audio_pdata *pdata;
  84
  85         pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
  86         if (!pdata)
  87                 return ERR_PTR(-ENOMEM);
  88
  89         rsc = kcalloc(2, sizeof(*rsc), GFP_KERNEL);
  90         if (!rsc) {
  91                 kfree(pdata);
  92                 return ERR_PTR(-ENOMEM);
  93         }
  94
  95         rsc[0].start    = rsc[0].end = dev_priv->lpe_audio.irq;
  96         rsc[0].flags    = IORESOURCE_IRQ;
  97         rsc[0].name     = "hdmi-lpe-audio-irq";
  98
  99         rsc[1].start    = pci_resource_start(dev->pdev, 0) +
 100                 I915_HDMI_LPE_AUDIO_BASE;
 101         rsc[1].end      = pci_resource_start(dev->pdev, 0) +
 102                 I915_HDMI_LPE_AUDIO_BASE + I915_HDMI_LPE_AUDIO_SIZE - 1;
 103         rsc[1].flags    = IORESOURCE_MEM;
 104         rsc[1].name     = "hdmi-lpe-audio-mmio";
 105
 106         pinfo.parent = dev->dev;
 107         pinfo.name = "hdmi-lpe-audio";
 108         pinfo.id = -1;
 109         pinfo.res = rsc;
 110         pinfo.num_res = 2;
 111         pinfo.data = pdata;
 112         pinfo.size_data = sizeof(*pdata);
 113         pinfo.dma_mask = DMA_BIT_MASK(32);
 114
 115         pdata->num_pipes = INTEL_INFO(dev_priv)->num_pipes;
 116         pdata->num_ports = IS_CHERRYVIEW(dev_priv) ? 3 : 2; /* B,C,D or B,C */
 117         pdata->port[0].pipe = -1;
 118         pdata->port[1].pipe = -1;
 119         pdata->port[2].pipe = -1;
 120         spin_lock_init(&pdata->lpe_audio_slock);
 121
 122         platdev = platform_device_register_full(&pinfo);
 123         if (IS_ERR(platdev)) {
 124                 ret = PTR_ERR(platdev);
 125                 DRM_ERROR("Failed to allocate LPE audio platform device\n");
 126                 goto err;
 127         }
 128
 129         kfree(rsc);
 130
 131         pm_runtime_forbid(&platdev->dev);
 132         pm_runtime_set_active(&platdev->dev);
 133         pm_runtime_enable(&platdev->dev);
 134
 135         return platdev;
 136
 137 err:
 138         kfree(rsc);
 139         kfree(pdata);
 140         return ERR_PTR(ret);
 141 }
 142
 143 static void lpe_audio_platdev_destroy(struct drm_i915_private *dev_priv)
 144 {
 145         /* XXX Note that platform_device_register_full() allocates a dma_mask
 146          * and never frees it. We can't free it here as we cannot guarantee
 147          * this is the last reference (i.e. that the dma_mask will not be
 148          * used after our unregister). So ee choose to leak the sizeof(u64)
 149          * allocation here - it should be fixed in the platform_device rather
 150          * than us fiddle with its internals.
 151          */
 152
 153         platform_device_unregister(dev_priv->lpe_audio.platdev);
 154 }
 155
 156 static void lpe_audio_irq_unmask(struct irq_data *d)
 157 {
 158 }
 159
 160 static void lpe_audio_irq_mask(struct irq_data *d)
 161 {
 162 }
 163
 164 static struct irq_chip lpe_audio_irqchip = {
 165         .name = "hdmi_lpe_audio_irqchip",
 166         .irq_mask = lpe_audio_irq_mask,
 167         .irq_unmask = lpe_audio_irq_unmask,
 168 };
 169
 170 static int lpe_audio_irq_init(struct drm_i915_private *dev_priv)
 171 {
 172         int irq = dev_priv->lpe_audio.irq;
 173
 174         WARN_ON(!intel_irqs_enabled(dev_priv));
 175         irq_set_chip_and_handler_name(irq,
 176                                 &lpe_audio_irqchip,
 177                                 handle_simple_irq,
 178                                 "hdmi_lpe_audio_irq_handler");
 179
 180         static const struct pci_device_id irq_quirk_ids[] = {
 181                 /* Dell Wyse 3040 */
 182                 {PCI_DEVICE_SUB(PCI_VENDOR_ID_INTEL, 0x22b0, 0x1028, 0x07c1)},
 183                 {}
 184         };
 185
 186         if (pci_dev_present(irq_quirk_ids))
 187                 return 0;
 188         return irq_set_chip_data(irq, dev_priv);
 189 }
 190
 191 static bool lpe_audio_detect(struct drm_i915_private *dev_priv)
 192 {
 193         int lpe_present = false;
 194
 195         if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
 196                 static const struct pci_device_id atom_hdaudio_ids[] = {
 197                         /* Baytrail */
 198                         {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0f04)},
 199                         /* Braswell */
 200                         {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2284)},
 201                         {}
 202                 };
 203
 204                 if (!pci_dev_present(atom_hdaudio_ids)) {
 205                         DRM_INFO("HDaudio controller not detected, using LPE audio instead\n");
 206                         lpe_present = true;
 207                 }
 208         }
 209         return lpe_present;
 210 }
 211
 212 static int lpe_audio_setup(struct drm_i915_private *dev_priv)
 213 {
 214         int ret;
 215
 216         dev_priv->lpe_audio.irq = irq_alloc_desc(0);
 217         if (dev_priv->lpe_audio.irq < 0) {
 218                 DRM_ERROR("Failed to allocate IRQ desc: %d\n",
 219                         dev_priv->lpe_audio.irq);
 220                 ret = dev_priv->lpe_audio.irq;
 221                 goto err;
 222         }
 223
 224         DRM_DEBUG("irq = %d\n", dev_priv->lpe_audio.irq);
 225
 226         ret = lpe_audio_irq_init(dev_priv);
 227
 228         if (ret) {
 229                 DRM_ERROR("Failed to initialize irqchip for lpe audio: %d\n",
 230                         ret);
 231                 goto err_free_irq;
 232         }
 233
 234         dev_priv->lpe_audio.platdev = lpe_audio_platdev_create(dev_priv);
 235
 236         if (IS_ERR(dev_priv->lpe_audio.platdev)) {
 237                 ret = PTR_ERR(dev_priv->lpe_audio.platdev);
 238                 DRM_ERROR("Failed to create lpe audio platform device: %d\n",
 239                         ret);
 240                 goto err_free_irq;
 241         }
 242
 243         /* enable chicken bit; at least this is required for Dell Wyse 3040
 244          * with DP outputs (but only sometimes by some reason!)
 245          */
 246         I915_WRITE(VLV_AUD_CHICKEN_BIT_REG, VLV_CHICKEN_BIT_DBG_ENABLE);
 247
 248         return 0;
 249 err_free_irq:
 250         irq_free_desc(dev_priv->lpe_audio.irq);
 251 err:
 252         dev_priv->lpe_audio.irq = -1;
 253         dev_priv->lpe_audio.platdev = NULL;
 254         return ret;
 255 }
 256
 257 /**
 258  * intel_lpe_audio_irq_handler() - forwards the LPE audio irq
 259  * @dev_priv: the i915 drm device private data
 260  *
 261  * the LPE Audio irq is forwarded to the irq handler registered by LPE audio
 262  * driver.
 263  */
 264 void intel_lpe_audio_irq_handler(struct drm_i915_private *dev_priv)
 265 {
 266         int ret;
 267
 268         if (!HAS_LPE_AUDIO(dev_priv))
 269                 return;
 270
 271         ret = generic_handle_irq(dev_priv->lpe_audio.irq);
 272         if (ret)
 273                 DRM_ERROR_RATELIMITED("error handling LPE audio irq: %d\n",
 274                                 ret);
 275 }
 276
 277 /**
 278  * intel_lpe_audio_init() - detect and setup the bridge between HDMI LPE Audio
 279  * driver and i915
 280  * @dev_priv: the i915 drm device private data
 281  *
 282  * Return: 0 if successful. non-zero if detection or
 283  * llocation/initialization fails
 284  */
 285 int intel_lpe_audio_init(struct drm_i915_private *dev_priv)
 286 {
 287         int ret = -ENODEV;
 288
 289         if (lpe_audio_detect(dev_priv)) {
 290                 ret = lpe_audio_setup(dev_priv);
 291                 if (ret < 0)
 292                         DRM_ERROR("failed to setup LPE Audio bridge\n");
 293         }
 294         return ret;
 295 }
 296
 297 /**
 298  * intel_lpe_audio_teardown() - destroy the bridge between HDMI LPE
 299  * audio driver and i915
 300  * @dev_priv: the i915 drm device private data
 301  *
 302  * release all the resources for LPE audio <-> i915 bridge.
 303  */
 304 void intel_lpe_audio_teardown(struct drm_i915_private *dev_priv)
 305 {
 306         struct irq_desc *desc;
 307
 308         if (!HAS_LPE_AUDIO(dev_priv))
 309                 return;
 310
 311         desc = irq_to_desc(dev_priv->lpe_audio.irq);
 312
 313         lpe_audio_platdev_destroy(dev_priv);
 314
 315         irq_free_desc(dev_priv->lpe_audio.irq);
 316 }
 317
 318
 319 /**
 320  * intel_lpe_audio_notify() - notify lpe audio event
 321  * audio driver and i915
 322  * @dev_priv: the i915 drm device private data
 323  * @pipe: pipe
 324  * @port: port
 325  * @eld : ELD data
 326  * @ls_clock: Link symbol clock in kHz
 327  * @dp_output: Driving a DP output?
 328  *
 329  * Notify lpe audio driver of eld change.
 330  */
 331 void intel_lpe_audio_notify(struct drm_i915_private *dev_priv,
 332                             enum pipe pipe, enum port port,
 333                             const void *eld, int ls_clock, bool dp_output)
 334 {
 335         unsigned long irqflags;
 336         struct intel_hdmi_lpe_audio_pdata *pdata;
 337         struct intel_hdmi_lpe_audio_port_pdata *ppdata;
 338         u32 audio_enable;
 339
 340         if (!HAS_LPE_AUDIO(dev_priv))
 341                 return;
 342
 343         pdata = dev_get_platdata(&dev_priv->lpe_audio.platdev->dev);
 344         ppdata = &pdata->port[port - PORT_B];
 345
 346         spin_lock_irqsave(&pdata->lpe_audio_slock, irqflags);
 347
 348         audio_enable = I915_READ(VLV_AUD_PORT_EN_DBG(port));
 349
 350         if (eld != NULL) {
 351                 memcpy(ppdata->eld, eld, HDMI_MAX_ELD_BYTES);
 352                 ppdata->pipe = pipe;
 353                 ppdata->ls_clock = ls_clock;
 354                 ppdata->dp_output = dp_output;
 355
 356                 /* Unmute the amp for both DP and HDMI */
 357                 I915_WRITE(VLV_AUD_PORT_EN_DBG(port),
 358                            audio_enable & ~VLV_AMP_MUTE);
 359         } else {
 360                 memset(ppdata->eld, 0, HDMI_MAX_ELD_BYTES);
 361                 ppdata->pipe = -1;
 362                 ppdata->ls_clock = 0;
 363                 ppdata->dp_output = false;
 364
 365                 /* Mute the amp for both DP and HDMI */
 366                 I915_WRITE(VLV_AUD_PORT_EN_DBG(port),
 367                            audio_enable | VLV_AMP_MUTE);
 368         }
 369
 370         if (pdata->notify_audio_lpe)
 371                 pdata->notify_audio_lpe(dev_priv->lpe_audio.platdev, port - PORT_B);
 372
 373         spin_unlock_irqrestore(&pdata->lpe_audio_slock, irqflags);
 374 }