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/delay.h> 65 #include <linux/device.h> 66 #include <linux/irq.h> 67 #include <linux/pci.h> 68 #include <linux/platform_device.h> 69 #include <linux/pm_runtime.h> 70 71 #include <drm/intel_lpe_audio.h> 72 73 #include "i915_drv.h" 74 #include "intel_lpe_audio.h" 75 76 #define HAS_LPE_AUDIO(dev_priv) ((dev_priv)->lpe_audio.platdev != NULL) 77 78 static struct platform_device * 79 lpe_audio_platdev_create(struct drm_i915_private *dev_priv) 80 { 81 struct drm_device *dev = &dev_priv->drm; 82 struct platform_device_info pinfo = {}; 83 struct resource *rsc; 84 struct platform_device *platdev; 85 struct intel_hdmi_lpe_audio_pdata *pdata; 86 87 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL); 88 if (!pdata) 89 return ERR_PTR(-ENOMEM); 90 91 rsc = kcalloc(2, sizeof(*rsc), GFP_KERNEL); 92 if (!rsc) { 93 kfree(pdata); 94 return ERR_PTR(-ENOMEM); 95 } 96 97 rsc[0].start = rsc[0].end = dev_priv->lpe_audio.irq; 98 rsc[0].flags = IORESOURCE_IRQ; 99 rsc[0].name = "hdmi-lpe-audio-irq"; 100 101 rsc[1].start = pci_resource_start(dev->pdev, 0) + 102 I915_HDMI_LPE_AUDIO_BASE; 103 rsc[1].end = pci_resource_start(dev->pdev, 0) + 104 I915_HDMI_LPE_AUDIO_BASE + I915_HDMI_LPE_AUDIO_SIZE - 1; 105 rsc[1].flags = IORESOURCE_MEM; 106 rsc[1].name = "hdmi-lpe-audio-mmio"; 107 108 pinfo.parent = dev->dev; 109 pinfo.name = "hdmi-lpe-audio"; 110 pinfo.id = -1; 111 pinfo.res = rsc; 112 pinfo.num_res = 2; 113 pinfo.data = pdata; 114 pinfo.size_data = sizeof(*pdata); 115 pinfo.dma_mask = DMA_BIT_MASK(32); 116 117 pdata->num_pipes = INTEL_NUM_PIPES(dev_priv); 118 pdata->num_ports = IS_CHERRYVIEW(dev_priv) ? 3 : 2; /* B,C,D or B,C */ 119 pdata->port[0].pipe = -1; 120 pdata->port[1].pipe = -1; 121 pdata->port[2].pipe = -1; 122 spin_lock_init(&pdata->lpe_audio_slock); 123 124 platdev = platform_device_register_full(&pinfo); 125 kfree(rsc); 126 kfree(pdata); 127 128 if (IS_ERR(platdev)) { 129 DRM_ERROR("Failed to allocate LPE audio platform device\n"); 130 return platdev; 131 } 132 133 pm_runtime_no_callbacks(&platdev->dev); 134 135 return platdev; 136 } 137 138 static void lpe_audio_platdev_destroy(struct drm_i915_private *dev_priv) 139 { 140 /* XXX Note that platform_device_register_full() allocates a dma_mask 141 * and never frees it. We can't free it here as we cannot guarantee 142 * this is the last reference (i.e. that the dma_mask will not be 143 * used after our unregister). So ee choose to leak the sizeof(u64) 144 * allocation here - it should be fixed in the platform_device rather 145 * than us fiddle with its internals. 146 */ 147 148 platform_device_unregister(dev_priv->lpe_audio.platdev); 149 } 150 151 static void lpe_audio_irq_unmask(struct irq_data *d) 152 { 153 } 154 155 static void lpe_audio_irq_mask(struct irq_data *d) 156 { 157 } 158 159 static struct irq_chip lpe_audio_irqchip = { 160 .name = "hdmi_lpe_audio_irqchip", 161 .irq_mask = lpe_audio_irq_mask, 162 .irq_unmask = lpe_audio_irq_unmask, 163 }; 164 165 static int lpe_audio_irq_init(struct drm_i915_private *dev_priv) 166 { 167 int irq = dev_priv->lpe_audio.irq; 168 169 WARN_ON(!intel_irqs_enabled(dev_priv)); 170 irq_set_chip_and_handler_name(irq, 171 &lpe_audio_irqchip, 172 handle_simple_irq, 173 "hdmi_lpe_audio_irq_handler"); 174 175 return irq_set_chip_data(irq, dev_priv); 176 } 177 178 static bool lpe_audio_detect(struct drm_i915_private *dev_priv) 179 { 180 int lpe_present = false; 181 182 if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) { 183 static const struct pci_device_id atom_hdaudio_ids[] = { 184 /* Baytrail */ 185 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0f04)}, 186 /* Braswell */ 187 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2284)}, 188 {} 189 }; 190 191 if (!pci_dev_present(atom_hdaudio_ids)) { 192 DRM_INFO("HDaudio controller not detected, using LPE audio instead\n"); 193 lpe_present = true; 194 } 195 } 196 return lpe_present; 197 } 198 199 static int lpe_audio_setup(struct drm_i915_private *dev_priv) 200 { 201 int ret; 202 203 dev_priv->lpe_audio.irq = irq_alloc_desc(0); 204 if (dev_priv->lpe_audio.irq < 0) { 205 DRM_ERROR("Failed to allocate IRQ desc: %d\n", 206 dev_priv->lpe_audio.irq); 207 ret = dev_priv->lpe_audio.irq; 208 goto err; 209 } 210 211 DRM_DEBUG("irq = %d\n", dev_priv->lpe_audio.irq); 212 213 ret = lpe_audio_irq_init(dev_priv); 214 215 if (ret) { 216 DRM_ERROR("Failed to initialize irqchip for lpe audio: %d\n", 217 ret); 218 goto err_free_irq; 219 } 220 221 dev_priv->lpe_audio.platdev = lpe_audio_platdev_create(dev_priv); 222 223 if (IS_ERR(dev_priv->lpe_audio.platdev)) { 224 ret = PTR_ERR(dev_priv->lpe_audio.platdev); 225 DRM_ERROR("Failed to create lpe audio platform device: %d\n", 226 ret); 227 goto err_free_irq; 228 } 229 230 /* enable chicken bit; at least this is required for Dell Wyse 3040 231 * with DP outputs (but only sometimes by some reason!) 232 */ 233 I915_WRITE(VLV_AUD_CHICKEN_BIT_REG, VLV_CHICKEN_BIT_DBG_ENABLE); 234 235 return 0; 236 err_free_irq: 237 irq_free_desc(dev_priv->lpe_audio.irq); 238 err: 239 dev_priv->lpe_audio.irq = -1; 240 dev_priv->lpe_audio.platdev = NULL; 241 return ret; 242 } 243 244 /** 245 * intel_lpe_audio_irq_handler() - forwards the LPE audio irq 246 * @dev_priv: the i915 drm device private data 247 * 248 * the LPE Audio irq is forwarded to the irq handler registered by LPE audio 249 * driver. 250 */ 251 void intel_lpe_audio_irq_handler(struct drm_i915_private *dev_priv) 252 { 253 int ret; 254 255 if (!HAS_LPE_AUDIO(dev_priv)) 256 return; 257 258 ret = generic_handle_irq(dev_priv->lpe_audio.irq); 259 if (ret) 260 DRM_ERROR_RATELIMITED("error handling LPE audio irq: %d\n", 261 ret); 262 } 263 264 /** 265 * intel_lpe_audio_init() - detect and setup the bridge between HDMI LPE Audio 266 * driver and i915 267 * @dev_priv: the i915 drm device private data 268 * 269 * Return: 0 if successful. non-zero if detection or 270 * llocation/initialization fails 271 */ 272 int intel_lpe_audio_init(struct drm_i915_private *dev_priv) 273 { 274 int ret = -ENODEV; 275 276 if (lpe_audio_detect(dev_priv)) { 277 ret = lpe_audio_setup(dev_priv); 278 if (ret < 0) 279 DRM_ERROR("failed to setup LPE Audio bridge\n"); 280 } 281 return ret; 282 } 283 284 /** 285 * intel_lpe_audio_teardown() - destroy the bridge between HDMI LPE 286 * audio driver and i915 287 * @dev_priv: the i915 drm device private data 288 * 289 * release all the resources for LPE audio <-> i915 bridge. 290 */ 291 void intel_lpe_audio_teardown(struct drm_i915_private *dev_priv) 292 { 293 struct irq_desc *desc; 294 295 if (!HAS_LPE_AUDIO(dev_priv)) 296 return; 297 298 desc = irq_to_desc(dev_priv->lpe_audio.irq); 299 300 lpe_audio_platdev_destroy(dev_priv); 301 302 irq_free_desc(dev_priv->lpe_audio.irq); 303 304 dev_priv->lpe_audio.irq = -1; 305 dev_priv->lpe_audio.platdev = NULL; 306 } 307 308 /** 309 * intel_lpe_audio_notify() - notify lpe audio event 310 * audio driver and i915 311 * @dev_priv: the i915 drm device private data 312 * @pipe: pipe 313 * @port: port 314 * @eld : ELD data 315 * @ls_clock: Link symbol clock in kHz 316 * @dp_output: Driving a DP output? 317 * 318 * Notify lpe audio driver of eld change. 319 */ 320 void intel_lpe_audio_notify(struct drm_i915_private *dev_priv, 321 enum pipe pipe, enum port port, 322 const void *eld, int ls_clock, bool dp_output) 323 { 324 unsigned long irqflags; 325 struct intel_hdmi_lpe_audio_pdata *pdata; 326 struct intel_hdmi_lpe_audio_port_pdata *ppdata; 327 u32 audio_enable; 328 329 if (!HAS_LPE_AUDIO(dev_priv)) 330 return; 331 332 pdata = dev_get_platdata(&dev_priv->lpe_audio.platdev->dev); 333 ppdata = &pdata->port[port - PORT_B]; 334 335 spin_lock_irqsave(&pdata->lpe_audio_slock, irqflags); 336 337 audio_enable = I915_READ(VLV_AUD_PORT_EN_DBG(port)); 338 339 if (eld != NULL) { 340 memcpy(ppdata->eld, eld, HDMI_MAX_ELD_BYTES); 341 ppdata->pipe = pipe; 342 ppdata->ls_clock = ls_clock; 343 ppdata->dp_output = dp_output; 344 345 /* Unmute the amp for both DP and HDMI */ 346 I915_WRITE(VLV_AUD_PORT_EN_DBG(port), 347 audio_enable & ~VLV_AMP_MUTE); 348 } else { 349 memset(ppdata->eld, 0, HDMI_MAX_ELD_BYTES); 350 ppdata->pipe = -1; 351 ppdata->ls_clock = 0; 352 ppdata->dp_output = false; 353 354 /* Mute the amp for both DP and HDMI */ 355 I915_WRITE(VLV_AUD_PORT_EN_DBG(port), 356 audio_enable | VLV_AMP_MUTE); 357 } 358 359 if (pdata->notify_audio_lpe) 360 pdata->notify_audio_lpe(dev_priv->lpe_audio.platdev, port - PORT_B); 361 362 spin_unlock_irqrestore(&pdata->lpe_audio_slock, irqflags); 363 } 364