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 *
lpe_audio_platdev_create(struct drm_i915_private * dev_priv)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
lpe_audio_platdev_destroy(struct drm_i915_private * dev_priv)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
lpe_audio_irq_unmask(struct irq_data * d)153 static void lpe_audio_irq_unmask(struct irq_data *d)
154 {
155 }
156
lpe_audio_irq_mask(struct irq_data * d)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
lpe_audio_irq_init(struct drm_i915_private * dev_priv)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
lpe_audio_detect(struct drm_i915_private * dev_priv)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
lpe_audio_setup(struct drm_i915_private * dev_priv)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 */
intel_lpe_audio_irq_handler(struct drm_i915_private * dev_priv)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 */
intel_lpe_audio_init(struct drm_i915_private * dev_priv)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 */
intel_lpe_audio_teardown(struct drm_i915_private * dev_priv)298 void intel_lpe_audio_teardown(struct drm_i915_private *dev_priv)
299 {
300 struct irq_desc *desc;
301
302 if (!HAS_LPE_AUDIO(dev_priv))
303 return;
304
305 desc = irq_to_desc(dev_priv->lpe_audio.irq);
306
307 lpe_audio_platdev_destroy(dev_priv);
308
309 irq_free_desc(dev_priv->lpe_audio.irq);
310
311 dev_priv->lpe_audio.irq = -1;
312 dev_priv->lpe_audio.platdev = NULL;
313 }
314
315 /**
316 * intel_lpe_audio_notify() - notify lpe audio event
317 * audio driver and i915
318 * @dev_priv: the i915 drm device private data
319 * @pipe: pipe
320 * @port: port
321 * @eld : ELD data
322 * @ls_clock: Link symbol clock in kHz
323 * @dp_output: Driving a DP output?
324 *
325 * Notify lpe audio driver of eld change.
326 */
intel_lpe_audio_notify(struct drm_i915_private * dev_priv,enum pipe pipe,enum port port,const void * eld,int ls_clock,bool dp_output)327 void intel_lpe_audio_notify(struct drm_i915_private *dev_priv,
328 enum pipe pipe, enum port port,
329 const void *eld, int ls_clock, bool dp_output)
330 {
331 unsigned long irqflags;
332 struct intel_hdmi_lpe_audio_pdata *pdata;
333 struct intel_hdmi_lpe_audio_port_pdata *ppdata;
334 u32 audio_enable;
335
336 if (!HAS_LPE_AUDIO(dev_priv))
337 return;
338
339 pdata = dev_get_platdata(&dev_priv->lpe_audio.platdev->dev);
340 ppdata = &pdata->port[port - PORT_B];
341
342 spin_lock_irqsave(&pdata->lpe_audio_slock, irqflags);
343
344 audio_enable = intel_de_read(dev_priv, VLV_AUD_PORT_EN_DBG(port));
345
346 if (eld != NULL) {
347 memcpy(ppdata->eld, eld, HDMI_MAX_ELD_BYTES);
348 ppdata->pipe = pipe;
349 ppdata->ls_clock = ls_clock;
350 ppdata->dp_output = dp_output;
351
352 /* Unmute the amp for both DP and HDMI */
353 intel_de_write(dev_priv, VLV_AUD_PORT_EN_DBG(port),
354 audio_enable & ~VLV_AMP_MUTE);
355 } else {
356 memset(ppdata->eld, 0, HDMI_MAX_ELD_BYTES);
357 ppdata->pipe = -1;
358 ppdata->ls_clock = 0;
359 ppdata->dp_output = false;
360
361 /* Mute the amp for both DP and HDMI */
362 intel_de_write(dev_priv, VLV_AUD_PORT_EN_DBG(port),
363 audio_enable | VLV_AMP_MUTE);
364 }
365
366 if (pdata->notify_audio_lpe)
367 pdata->notify_audio_lpe(dev_priv->lpe_audio.platdev, port - PORT_B);
368
369 spin_unlock_irqrestore(&pdata->lpe_audio_slock, irqflags);
370 }
371