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