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_de.h" 75 #include "intel_lpe_audio.h" 76 77 #define HAS_LPE_AUDIO(dev_priv) ((dev_priv)->lpe_audio.platdev != NULL) 78 79 static struct platform_device * 80 lpe_audio_platdev_create(struct drm_i915_private *dev_priv) 81 { 82 struct drm_device *dev = &dev_priv->drm; 83 struct pci_dev *pdev = to_pci_dev(dev->dev); 84 struct platform_device_info pinfo = {}; 85 struct resource *rsc; 86 struct platform_device *platdev; 87 struct intel_hdmi_lpe_audio_pdata *pdata; 88 89 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL); 90 if (!pdata) 91 return ERR_PTR(-ENOMEM); 92 93 rsc = kcalloc(2, sizeof(*rsc), GFP_KERNEL); 94 if (!rsc) { 95 kfree(pdata); 96 return ERR_PTR(-ENOMEM); 97 } 98 99 rsc[0].start = rsc[0].end = dev_priv->lpe_audio.irq; 100 rsc[0].flags = IORESOURCE_IRQ; 101 rsc[0].name = "hdmi-lpe-audio-irq"; 102 103 rsc[1].start = pci_resource_start(pdev, 0) + 104 I915_HDMI_LPE_AUDIO_BASE; 105 rsc[1].end = pci_resource_start(pdev, 0) + 106 I915_HDMI_LPE_AUDIO_BASE + I915_HDMI_LPE_AUDIO_SIZE - 1; 107 rsc[1].flags = IORESOURCE_MEM; 108 rsc[1].name = "hdmi-lpe-audio-mmio"; 109 110 pinfo.parent = dev->dev; 111 pinfo.name = "hdmi-lpe-audio"; 112 pinfo.id = -1; 113 pinfo.res = rsc; 114 pinfo.num_res = 2; 115 pinfo.data = pdata; 116 pinfo.size_data = sizeof(*pdata); 117 pinfo.dma_mask = DMA_BIT_MASK(32); 118 119 pdata->num_pipes = INTEL_NUM_PIPES(dev_priv); 120 pdata->num_ports = IS_CHERRYVIEW(dev_priv) ? 3 : 2; /* B,C,D or B,C */ 121 pdata->port[0].pipe = -1; 122 pdata->port[1].pipe = -1; 123 pdata->port[2].pipe = -1; 124 spin_lock_init(&pdata->lpe_audio_slock); 125 126 platdev = platform_device_register_full(&pinfo); 127 kfree(rsc); 128 kfree(pdata); 129 130 if (IS_ERR(platdev)) { 131 drm_err(&dev_priv->drm, 132 "Failed to allocate LPE audio platform device\n"); 133 return platdev; 134 } 135 136 pm_runtime_no_callbacks(&platdev->dev); 137 138 return platdev; 139 } 140 141 static void lpe_audio_platdev_destroy(struct drm_i915_private *dev_priv) 142 { 143 /* XXX Note that platform_device_register_full() allocates a dma_mask 144 * and never frees it. We can't free it here as we cannot guarantee 145 * this is the last reference (i.e. that the dma_mask will not be 146 * used after our unregister). So ee choose to leak the sizeof(u64) 147 * allocation here - it should be fixed in the platform_device rather 148 * than us fiddle with its internals. 149 */ 150 151 platform_device_unregister(dev_priv->lpe_audio.platdev); 152 } 153 154 static void lpe_audio_irq_unmask(struct irq_data *d) 155 { 156 } 157 158 static void lpe_audio_irq_mask(struct irq_data *d) 159 { 160 } 161 162 static struct irq_chip lpe_audio_irqchip = { 163 .name = "hdmi_lpe_audio_irqchip", 164 .irq_mask = lpe_audio_irq_mask, 165 .irq_unmask = lpe_audio_irq_unmask, 166 }; 167 168 static int lpe_audio_irq_init(struct drm_i915_private *dev_priv) 169 { 170 int irq = dev_priv->lpe_audio.irq; 171 172 drm_WARN_ON(&dev_priv->drm, !intel_irqs_enabled(dev_priv)); 173 irq_set_chip_and_handler_name(irq, 174 &lpe_audio_irqchip, 175 handle_simple_irq, 176 "hdmi_lpe_audio_irq_handler"); 177 178 return irq_set_chip_data(irq, dev_priv); 179 } 180 181 static bool lpe_audio_detect(struct drm_i915_private *dev_priv) 182 { 183 int lpe_present = false; 184 185 if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) { 186 static const struct pci_device_id atom_hdaudio_ids[] = { 187 /* Baytrail */ 188 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0f04)}, 189 /* Braswell */ 190 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2284)}, 191 {} 192 }; 193 194 if (!pci_dev_present(atom_hdaudio_ids)) { 195 drm_info(&dev_priv->drm, 196 "HDaudio controller not detected, using LPE audio instead\n"); 197 lpe_present = true; 198 } 199 } 200 return lpe_present; 201 } 202 203 static int lpe_audio_setup(struct drm_i915_private *dev_priv) 204 { 205 int ret; 206 207 dev_priv->lpe_audio.irq = irq_alloc_desc(0); 208 if (dev_priv->lpe_audio.irq < 0) { 209 drm_err(&dev_priv->drm, "Failed to allocate IRQ desc: %d\n", 210 dev_priv->lpe_audio.irq); 211 ret = dev_priv->lpe_audio.irq; 212 goto err; 213 } 214 215 drm_dbg(&dev_priv->drm, "irq = %d\n", dev_priv->lpe_audio.irq); 216 217 ret = lpe_audio_irq_init(dev_priv); 218 219 if (ret) { 220 drm_err(&dev_priv->drm, 221 "Failed to initialize irqchip for lpe audio: %d\n", 222 ret); 223 goto err_free_irq; 224 } 225 226 dev_priv->lpe_audio.platdev = lpe_audio_platdev_create(dev_priv); 227 228 if (IS_ERR(dev_priv->lpe_audio.platdev)) { 229 ret = PTR_ERR(dev_priv->lpe_audio.platdev); 230 drm_err(&dev_priv->drm, 231 "Failed to create lpe audio platform device: %d\n", 232 ret); 233 goto err_free_irq; 234 } 235 236 /* enable chicken bit; at least this is required for Dell Wyse 3040 237 * with DP outputs (but only sometimes by some reason!) 238 */ 239 intel_de_write(dev_priv, VLV_AUD_CHICKEN_BIT_REG, 240 VLV_CHICKEN_BIT_DBG_ENABLE); 241 242 return 0; 243 err_free_irq: 244 irq_free_desc(dev_priv->lpe_audio.irq); 245 err: 246 dev_priv->lpe_audio.irq = -1; 247 dev_priv->lpe_audio.platdev = NULL; 248 return ret; 249 } 250 251 /** 252 * intel_lpe_audio_irq_handler() - forwards the LPE audio irq 253 * @dev_priv: the i915 drm device private data 254 * 255 * the LPE Audio irq is forwarded to the irq handler registered by LPE audio 256 * driver. 257 */ 258 void intel_lpe_audio_irq_handler(struct drm_i915_private *dev_priv) 259 { 260 int ret; 261 262 if (!HAS_LPE_AUDIO(dev_priv)) 263 return; 264 265 ret = generic_handle_irq(dev_priv->lpe_audio.irq); 266 if (ret) 267 drm_err_ratelimited(&dev_priv->drm, 268 "error handling LPE audio irq: %d\n", ret); 269 } 270 271 /** 272 * intel_lpe_audio_init() - detect and setup the bridge between HDMI LPE Audio 273 * driver and i915 274 * @dev_priv: the i915 drm device private data 275 * 276 * Return: 0 if successful. non-zero if detection or 277 * llocation/initialization fails 278 */ 279 int intel_lpe_audio_init(struct drm_i915_private *dev_priv) 280 { 281 int ret = -ENODEV; 282 283 if (lpe_audio_detect(dev_priv)) { 284 ret = lpe_audio_setup(dev_priv); 285 if (ret < 0) 286 drm_err(&dev_priv->drm, 287 "failed to setup LPE Audio bridge\n"); 288 } 289 return ret; 290 } 291 292 /** 293 * intel_lpe_audio_teardown() - destroy the bridge between HDMI LPE 294 * audio driver and i915 295 * @dev_priv: the i915 drm device private data 296 * 297 * release all the resources for LPE audio <-> i915 bridge. 298 */ 299 void intel_lpe_audio_teardown(struct drm_i915_private *dev_priv) 300 { 301 if (!HAS_LPE_AUDIO(dev_priv)) 302 return; 303 304 lpe_audio_platdev_destroy(dev_priv); 305 306 irq_free_desc(dev_priv->lpe_audio.irq); 307 308 dev_priv->lpe_audio.irq = -1; 309 dev_priv->lpe_audio.platdev = NULL; 310 } 311 312 /** 313 * intel_lpe_audio_notify() - notify lpe audio event 314 * audio driver and i915 315 * @dev_priv: the i915 drm device private data 316 * @pipe: pipe 317 * @port: port 318 * @eld : ELD data 319 * @ls_clock: Link symbol clock in kHz 320 * @dp_output: Driving a DP output? 321 * 322 * Notify lpe audio driver of eld change. 323 */ 324 void intel_lpe_audio_notify(struct drm_i915_private *dev_priv, 325 enum pipe pipe, enum port port, 326 const void *eld, int ls_clock, bool dp_output) 327 { 328 unsigned long irqflags; 329 struct intel_hdmi_lpe_audio_pdata *pdata; 330 struct intel_hdmi_lpe_audio_port_pdata *ppdata; 331 u32 audio_enable; 332 333 if (!HAS_LPE_AUDIO(dev_priv)) 334 return; 335 336 pdata = dev_get_platdata(&dev_priv->lpe_audio.platdev->dev); 337 ppdata = &pdata->port[port - PORT_B]; 338 339 spin_lock_irqsave(&pdata->lpe_audio_slock, irqflags); 340 341 audio_enable = intel_de_read(dev_priv, VLV_AUD_PORT_EN_DBG(port)); 342 343 if (eld != NULL) { 344 memcpy(ppdata->eld, eld, HDMI_MAX_ELD_BYTES); 345 ppdata->pipe = pipe; 346 ppdata->ls_clock = ls_clock; 347 ppdata->dp_output = dp_output; 348 349 /* Unmute the amp for both DP and HDMI */ 350 intel_de_write(dev_priv, VLV_AUD_PORT_EN_DBG(port), 351 audio_enable & ~VLV_AMP_MUTE); 352 } else { 353 memset(ppdata->eld, 0, HDMI_MAX_ELD_BYTES); 354 ppdata->pipe = -1; 355 ppdata->ls_clock = 0; 356 ppdata->dp_output = false; 357 358 /* Mute the amp for both DP and HDMI */ 359 intel_de_write(dev_priv, VLV_AUD_PORT_EN_DBG(port), 360 audio_enable | VLV_AMP_MUTE); 361 } 362 363 if (pdata->notify_audio_lpe) 364 pdata->notify_audio_lpe(dev_priv->lpe_audio.platdev, port - PORT_B); 365 366 spin_unlock_irqrestore(&pdata->lpe_audio_slock, irqflags); 367 } 368