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 */
intel_lpe_audio_irq_handler(struct drm_i915_private * dev_priv)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 */
intel_lpe_audio_init(struct drm_i915_private * dev_priv)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 */
intel_lpe_audio_teardown(struct drm_i915_private * dev_priv)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 */
intel_lpe_audio_notify(struct drm_i915_private * dev_priv,enum i915_pipe pipe,enum port port,const void * eld,int ls_clock,bool dp_output)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