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/pci.h> 66 #include <linux/pm_runtime.h> 67 68 #include "i915_drv.h" 69 #include <linux/delay.h> 70 #include <drm/intel_lpe_audio.h> 71 72 #define HAS_LPE_AUDIO(dev_priv) ((dev_priv)->lpe_audio.platdev != NULL) 73 74 #if 0 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 pm_runtime_forbid(&platdev->dev); 136 pm_runtime_set_active(&platdev->dev); 137 pm_runtime_enable(&platdev->dev); 138 139 return platdev; 140 141 err: 142 kfree(rsc); 143 kfree(pdata); 144 return ERR_PTR(ret); 145 } 146 147 static void lpe_audio_platdev_destroy(struct drm_i915_private *dev_priv) 148 { 149 /* XXX Note that platform_device_register_full() allocates a dma_mask 150 * and never frees it. We can't free it here as we cannot guarantee 151 * this is the last reference (i.e. that the dma_mask will not be 152 * used after our unregister). So ee choose to leak the sizeof(u64) 153 * allocation here - it should be fixed in the platform_device rather 154 * than us fiddle with its internals. 155 */ 156 157 platform_device_unregister(dev_priv->lpe_audio.platdev); 158 } 159 160 static void lpe_audio_irq_unmask(struct irq_data *d) 161 { 162 } 163 164 static void lpe_audio_irq_mask(struct irq_data *d) 165 { 166 } 167 168 static struct irq_chip lpe_audio_irqchip = { 169 .name = "hdmi_lpe_audio_irqchip", 170 .irq_mask = lpe_audio_irq_mask, 171 .irq_unmask = lpe_audio_irq_unmask, 172 }; 173 174 static int lpe_audio_irq_init(struct drm_i915_private *dev_priv) 175 { 176 int irq = dev_priv->lpe_audio.irq; 177 178 WARN_ON(!intel_irqs_enabled(dev_priv)); 179 irq_set_chip_and_handler_name(irq, 180 &lpe_audio_irqchip, 181 handle_simple_irq, 182 "hdmi_lpe_audio_irq_handler"); 183 184 return irq_set_chip_data(irq, dev_priv); 185 } 186 187 static bool lpe_audio_detect(struct drm_i915_private *dev_priv) 188 { 189 int lpe_present = false; 190 191 if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) { 192 static const struct pci_device_id atom_hdaudio_ids[] = { 193 /* Baytrail */ 194 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0f04)}, 195 /* Braswell */ 196 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2284)}, 197 {} 198 }; 199 200 if (!pci_dev_present(atom_hdaudio_ids)) { 201 DRM_INFO("HDaudio controller not detected, using LPE audio instead\n"); 202 lpe_present = true; 203 } 204 } 205 return lpe_present; 206 } 207 208 static int lpe_audio_setup(struct drm_i915_private *dev_priv) 209 { 210 int ret; 211 212 dev_priv->lpe_audio.irq = irq_alloc_desc(0); 213 if (dev_priv->lpe_audio.irq < 0) { 214 DRM_ERROR("Failed to allocate IRQ desc: %d\n", 215 dev_priv->lpe_audio.irq); 216 ret = dev_priv->lpe_audio.irq; 217 goto err; 218 } 219 220 DRM_DEBUG("irq = %d\n", dev_priv->lpe_audio.irq); 221 222 ret = lpe_audio_irq_init(dev_priv); 223 224 if (ret) { 225 DRM_ERROR("Failed to initialize irqchip for lpe audio: %d\n", 226 ret); 227 goto err_free_irq; 228 } 229 230 dev_priv->lpe_audio.platdev = lpe_audio_platdev_create(dev_priv); 231 232 if (IS_ERR(dev_priv->lpe_audio.platdev)) { 233 ret = PTR_ERR(dev_priv->lpe_audio.platdev); 234 DRM_ERROR("Failed to create lpe audio platform device: %d\n", 235 ret); 236 goto err_free_irq; 237 } 238 239 /* enable chicken bit; at least this is required for Dell Wyse 3040 240 * with DP outputs (but only sometimes by some reason!) 241 */ 242 I915_WRITE(VLV_AUD_CHICKEN_BIT_REG, VLV_CHICKEN_BIT_DBG_ENABLE); 243 244 return 0; 245 err_free_irq: 246 irq_free_desc(dev_priv->lpe_audio.irq); 247 err: 248 dev_priv->lpe_audio.irq = -1; 249 dev_priv->lpe_audio.platdev = NULL; 250 return ret; 251 } 252 #endif 253 254 /** 255 * intel_lpe_audio_irq_handler() - forwards the LPE audio irq 256 * @dev_priv: the i915 drm device private data 257 * 258 * the LPE Audio irq is forwarded to the irq handler registered by LPE audio 259 * driver. 260 */ 261 void intel_lpe_audio_irq_handler(struct drm_i915_private *dev_priv) 262 { 263 #if 0 264 int ret; 265 266 if (!HAS_LPE_AUDIO(dev_priv)) 267 return; 268 269 ret = generic_handle_irq(dev_priv->lpe_audio.irq); 270 if (ret) 271 DRM_ERROR_RATELIMITED("error handling LPE audio irq: %d\n", 272 ret); 273 #endif 274 } 275 276 /** 277 * intel_lpe_audio_init() - detect and setup the bridge between HDMI LPE Audio 278 * driver and i915 279 * @dev_priv: the i915 drm device private data 280 * 281 * Return: 0 if successful. non-zero if detection or 282 * llocation/initialization fails 283 */ 284 int intel_lpe_audio_init(struct drm_i915_private *dev_priv) 285 { 286 int ret = -ENODEV; 287 288 #if 0 289 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 #endif 295 return ret; 296 } 297 298 /** 299 * intel_lpe_audio_teardown() - destroy the bridge between HDMI LPE 300 * audio driver and i915 301 * @dev_priv: the i915 drm device private data 302 * 303 * release all the resources for LPE audio <-> i915 bridge. 304 */ 305 void intel_lpe_audio_teardown(struct drm_i915_private *dev_priv) 306 { 307 #if 0 308 struct irq_desc *desc; 309 310 if (!HAS_LPE_AUDIO(dev_priv)) 311 return; 312 313 desc = irq_to_desc(dev_priv->lpe_audio.irq); 314 315 lpe_audio_platdev_destroy(dev_priv); 316 317 irq_free_desc(dev_priv->lpe_audio.irq); 318 #endif 319 } 320 321 322 /** 323 * intel_lpe_audio_notify() - notify lpe audio event 324 * audio driver and i915 325 * @dev_priv: the i915 drm device private data 326 * @pipe: pipe 327 * @port: port 328 * @eld : ELD data 329 * @ls_clock: Link symbol clock in kHz 330 * @dp_output: Driving a DP output? 331 * 332 * Notify lpe audio driver of eld change. 333 */ 334 void intel_lpe_audio_notify(struct drm_i915_private *dev_priv, 335 enum i915_pipe pipe, enum port port, 336 const void *eld, int ls_clock, bool dp_output) 337 { 338 #if 0 339 unsigned long irqflags; 340 struct intel_hdmi_lpe_audio_pdata *pdata; 341 struct intel_hdmi_lpe_audio_port_pdata *ppdata; 342 u32 audio_enable; 343 344 if (!HAS_LPE_AUDIO(dev_priv)) 345 return; 346 347 pdata = dev_get_platdata(&dev_priv->lpe_audio.platdev->dev); 348 ppdata = &pdata->port[port - PORT_B]; 349 350 spin_lock_irqsave(&pdata->lpe_audio_slock, irqflags); 351 352 audio_enable = I915_READ(VLV_AUD_PORT_EN_DBG(port)); 353 354 if (eld != NULL) { 355 memcpy(ppdata->eld, eld, HDMI_MAX_ELD_BYTES); 356 ppdata->pipe = pipe; 357 ppdata->ls_clock = ls_clock; 358 ppdata->dp_output = dp_output; 359 360 /* Unmute the amp for both DP and HDMI */ 361 I915_WRITE(VLV_AUD_PORT_EN_DBG(port), 362 audio_enable & ~VLV_AMP_MUTE); 363 } else { 364 memset(ppdata->eld, 0, HDMI_MAX_ELD_BYTES); 365 ppdata->pipe = -1; 366 ppdata->ls_clock = 0; 367 ppdata->dp_output = false; 368 369 /* Mute the amp for both DP and HDMI */ 370 I915_WRITE(VLV_AUD_PORT_EN_DBG(port), 371 audio_enable | VLV_AMP_MUTE); 372 } 373 374 if (pdata->notify_audio_lpe) 375 pdata->notify_audio_lpe(dev_priv->lpe_audio.platdev, port - PORT_B); 376 377 spin_unlock_irqrestore(&pdata->lpe_audio_slock, irqflags); 378 #endif 379 } 380