2 * Copyright © 2016 Intel Corporation
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:
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
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
24 * Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
25 * Jerome Anand <jerome.anand@intel.com>
26 * based on VED patches
31 * DOC: LPE Audio integration for HDMI or DP playback
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.
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
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.
56 * The MMIO/REG platform resources are created according to the registers
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.
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>
70 #include <linux/delay.h>
71 #include <drm/intel_lpe_audio.h>
73 #define HAS_LPE_AUDIO(dev_priv) ((dev_priv)->lpe_audio.platdev != NULL)
75 static struct platform_device *
76 lpe_audio_platdev_create(struct drm_i915_private *dev_priv)
79 struct drm_device *dev = &dev_priv->drm;
80 struct platform_device_info pinfo = {};
82 struct platform_device *platdev;
83 struct intel_hdmi_lpe_audio_pdata *pdata;
85 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
87 return ERR_PTR(-ENOMEM);
89 rsc = kcalloc(2, sizeof(*rsc), GFP_KERNEL);
92 return ERR_PTR(-ENOMEM);
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";
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";
106 pinfo.parent = dev->dev;
107 pinfo.name = "hdmi-lpe-audio";
112 pinfo.size_data = sizeof(*pdata);
113 pinfo.dma_mask = DMA_BIT_MASK(32);
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);
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");
131 pm_runtime_no_callbacks(&platdev->dev);
141 static void lpe_audio_platdev_destroy(struct drm_i915_private *dev_priv)
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.
151 platform_device_unregister(dev_priv->lpe_audio.platdev);
154 static void lpe_audio_irq_unmask(struct irq_data *d)
158 static void lpe_audio_irq_mask(struct irq_data *d)
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,
168 static int lpe_audio_irq_init(struct drm_i915_private *dev_priv)
170 int irq = dev_priv->lpe_audio.irq;
172 WARN_ON(!intel_irqs_enabled(dev_priv));
173 irq_set_chip_and_handler_name(irq,
176 "hdmi_lpe_audio_irq_handler");
178 return irq_set_chip_data(irq, dev_priv);
181 static bool lpe_audio_detect(struct drm_i915_private *dev_priv)
183 int lpe_present = false;
185 if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
186 static const struct pci_device_id atom_hdaudio_ids[] = {
188 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0f04)},
190 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2284)},
194 if (!pci_dev_present(atom_hdaudio_ids)) {
195 DRM_INFO("%s\n", "HDaudio controller not detected, using LPE audio instead\n");
202 static int lpe_audio_setup(struct drm_i915_private *dev_priv)
206 dev_priv->lpe_audio.irq = irq_alloc_desc(0);
207 if (dev_priv->lpe_audio.irq < 0) {
208 DRM_ERROR("Failed to allocate IRQ desc: %d\n",
209 dev_priv->lpe_audio.irq);
210 ret = dev_priv->lpe_audio.irq;
214 DRM_DEBUG("irq = %d\n", dev_priv->lpe_audio.irq);
216 ret = lpe_audio_irq_init(dev_priv);
219 DRM_ERROR("Failed to initialize irqchip for lpe audio: %d\n",
224 dev_priv->lpe_audio.platdev = lpe_audio_platdev_create(dev_priv);
226 if (IS_ERR(dev_priv->lpe_audio.platdev)) {
227 ret = PTR_ERR(dev_priv->lpe_audio.platdev);
228 DRM_ERROR("Failed to create lpe audio platform device: %d\n",
233 /* enable chicken bit; at least this is required for Dell Wyse 3040
234 * with DP outputs (but only sometimes by some reason!)
236 I915_WRITE(VLV_AUD_CHICKEN_BIT_REG, VLV_CHICKEN_BIT_DBG_ENABLE);
240 irq_free_desc(dev_priv->lpe_audio.irq);
242 dev_priv->lpe_audio.irq = -1;
243 dev_priv->lpe_audio.platdev = NULL;
248 * intel_lpe_audio_irq_handler() - forwards the LPE audio irq
249 * @dev_priv: the i915 drm device private data
251 * the LPE Audio irq is forwarded to the irq handler registered by LPE audio
254 void intel_lpe_audio_irq_handler(struct drm_i915_private *dev_priv)
258 if (!HAS_LPE_AUDIO(dev_priv))
261 ret = generic_handle_irq(dev_priv->lpe_audio.irq);
263 DRM_ERROR_RATELIMITED("error handling LPE audio irq: %d\n",
268 * intel_lpe_audio_init() - detect and setup the bridge between HDMI LPE Audio
270 * @dev_priv: the i915 drm device private data
272 * Return: 0 if successful. non-zero if detection or
273 * llocation/initialization fails
275 int intel_lpe_audio_init(struct drm_i915_private *dev_priv)
279 if (lpe_audio_detect(dev_priv)) {
280 ret = lpe_audio_setup(dev_priv);
282 DRM_ERROR("failed to setup LPE Audio bridge\n");
288 * intel_lpe_audio_teardown() - destroy the bridge between HDMI LPE
289 * audio driver and i915
290 * @dev_priv: the i915 drm device private data
292 * release all the resources for LPE audio <-> i915 bridge.
294 void intel_lpe_audio_teardown(struct drm_i915_private *dev_priv)
296 struct irq_desc *desc;
298 if (!HAS_LPE_AUDIO(dev_priv))
301 desc = irq_to_desc(dev_priv->lpe_audio.irq);
303 lpe_audio_platdev_destroy(dev_priv);
305 irq_free_desc(dev_priv->lpe_audio.irq);
307 dev_priv->lpe_audio.irq = -1;
308 dev_priv->lpe_audio.platdev = NULL;
312 * intel_lpe_audio_notify() - notify lpe audio event
313 * audio driver and i915
314 * @dev_priv: the i915 drm device private data
318 * @ls_clock: Link symbol clock in kHz
319 * @dp_output: Driving a DP output?
321 * Notify lpe audio driver of eld change.
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)
327 unsigned long irqflags;
328 struct intel_hdmi_lpe_audio_pdata *pdata;
329 struct intel_hdmi_lpe_audio_port_pdata *ppdata;
332 if (!HAS_LPE_AUDIO(dev_priv))
335 pdata = dev_get_platdata(&dev_priv->lpe_audio.platdev->dev);
336 ppdata = &pdata->port[port - PORT_B];
338 spin_lock_irqsave(&pdata->lpe_audio_slock, irqflags);
340 audio_enable = I915_READ(VLV_AUD_PORT_EN_DBG(port));
343 memcpy(ppdata->eld, eld, HDMI_MAX_ELD_BYTES);
345 ppdata->ls_clock = ls_clock;
346 ppdata->dp_output = dp_output;
348 /* Unmute the amp for both DP and HDMI */
349 I915_WRITE(VLV_AUD_PORT_EN_DBG(port),
350 audio_enable & ~VLV_AMP_MUTE);
352 memset(ppdata->eld, 0, HDMI_MAX_ELD_BYTES);
354 ppdata->ls_clock = 0;
355 ppdata->dp_output = false;
357 /* Mute the amp for both DP and HDMI */
358 I915_WRITE(VLV_AUD_PORT_EN_DBG(port),
359 audio_enable | VLV_AMP_MUTE);
362 if (pdata->notify_audio_lpe)
363 pdata->notify_audio_lpe(dev_priv->lpe_audio.platdev, port - PORT_B);
365 spin_unlock_irqrestore(&pdata->lpe_audio_slock, irqflags);