Merge branch 'akpm' (patches from Andrew)
[linux/fpc-iii.git] / drivers / gpu / drm / i915 / display / intel_lpe_audio.c
blob0b67f7887cd0b0b13d0703f20f867bb377b14628
1 /*
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
13 * Software.
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.
23 * Authors:
24 * Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
25 * Jerome Anand <jerome.anand@intel.com>
26 * based on VED patches
30 /**
31 * DOC: LPE Audio integration for HDMI or DP playback
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.
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
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.
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.
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>
71 #include <drm/intel_lpe_audio.h>
73 #include "i915_drv.h"
74 #include "intel_lpe_audio.h"
76 #define HAS_LPE_AUDIO(dev_priv) ((dev_priv)->lpe_audio.platdev != NULL)
78 static struct platform_device *
79 lpe_audio_platdev_create(struct drm_i915_private *dev_priv)
81 struct drm_device *dev = &dev_priv->drm;
82 struct platform_device_info pinfo = {};
83 struct resource *rsc;
84 struct platform_device *platdev;
85 struct intel_hdmi_lpe_audio_pdata *pdata;
87 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
88 if (!pdata)
89 return ERR_PTR(-ENOMEM);
91 rsc = kcalloc(2, sizeof(*rsc), GFP_KERNEL);
92 if (!rsc) {
93 kfree(pdata);
94 return ERR_PTR(-ENOMEM);
97 rsc[0].start = rsc[0].end = dev_priv->lpe_audio.irq;
98 rsc[0].flags = IORESOURCE_IRQ;
99 rsc[0].name = "hdmi-lpe-audio-irq";
101 rsc[1].start = pci_resource_start(dev->pdev, 0) +
102 I915_HDMI_LPE_AUDIO_BASE;
103 rsc[1].end = pci_resource_start(dev->pdev, 0) +
104 I915_HDMI_LPE_AUDIO_BASE + I915_HDMI_LPE_AUDIO_SIZE - 1;
105 rsc[1].flags = IORESOURCE_MEM;
106 rsc[1].name = "hdmi-lpe-audio-mmio";
108 pinfo.parent = dev->dev;
109 pinfo.name = "hdmi-lpe-audio";
110 pinfo.id = -1;
111 pinfo.res = rsc;
112 pinfo.num_res = 2;
113 pinfo.data = pdata;
114 pinfo.size_data = sizeof(*pdata);
115 pinfo.dma_mask = DMA_BIT_MASK(32);
117 pdata->num_pipes = INTEL_NUM_PIPES(dev_priv);
118 pdata->num_ports = IS_CHERRYVIEW(dev_priv) ? 3 : 2; /* B,C,D or B,C */
119 pdata->port[0].pipe = -1;
120 pdata->port[1].pipe = -1;
121 pdata->port[2].pipe = -1;
122 spin_lock_init(&pdata->lpe_audio_slock);
124 platdev = platform_device_register_full(&pinfo);
125 kfree(rsc);
126 kfree(pdata);
128 if (IS_ERR(platdev)) {
129 DRM_ERROR("Failed to allocate LPE audio platform device\n");
130 return platdev;
133 pm_runtime_no_callbacks(&platdev->dev);
135 return platdev;
138 static void lpe_audio_platdev_destroy(struct drm_i915_private *dev_priv)
140 /* XXX Note that platform_device_register_full() allocates a dma_mask
141 * and never frees it. We can't free it here as we cannot guarantee
142 * this is the last reference (i.e. that the dma_mask will not be
143 * used after our unregister). So ee choose to leak the sizeof(u64)
144 * allocation here - it should be fixed in the platform_device rather
145 * than us fiddle with its internals.
148 platform_device_unregister(dev_priv->lpe_audio.platdev);
151 static void lpe_audio_irq_unmask(struct irq_data *d)
155 static void lpe_audio_irq_mask(struct irq_data *d)
159 static struct irq_chip lpe_audio_irqchip = {
160 .name = "hdmi_lpe_audio_irqchip",
161 .irq_mask = lpe_audio_irq_mask,
162 .irq_unmask = lpe_audio_irq_unmask,
165 static int lpe_audio_irq_init(struct drm_i915_private *dev_priv)
167 int irq = dev_priv->lpe_audio.irq;
169 WARN_ON(!intel_irqs_enabled(dev_priv));
170 irq_set_chip_and_handler_name(irq,
171 &lpe_audio_irqchip,
172 handle_simple_irq,
173 "hdmi_lpe_audio_irq_handler");
175 return irq_set_chip_data(irq, dev_priv);
178 static bool lpe_audio_detect(struct drm_i915_private *dev_priv)
180 int lpe_present = false;
182 if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
183 static const struct pci_device_id atom_hdaudio_ids[] = {
184 /* Baytrail */
185 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0f04)},
186 /* Braswell */
187 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2284)},
191 if (!pci_dev_present(atom_hdaudio_ids)) {
192 DRM_INFO("HDaudio controller not detected, using LPE audio instead\n");
193 lpe_present = true;
196 return lpe_present;
199 static int lpe_audio_setup(struct drm_i915_private *dev_priv)
201 int ret;
203 dev_priv->lpe_audio.irq = irq_alloc_desc(0);
204 if (dev_priv->lpe_audio.irq < 0) {
205 DRM_ERROR("Failed to allocate IRQ desc: %d\n",
206 dev_priv->lpe_audio.irq);
207 ret = dev_priv->lpe_audio.irq;
208 goto err;
211 DRM_DEBUG("irq = %d\n", dev_priv->lpe_audio.irq);
213 ret = lpe_audio_irq_init(dev_priv);
215 if (ret) {
216 DRM_ERROR("Failed to initialize irqchip for lpe audio: %d\n",
217 ret);
218 goto err_free_irq;
221 dev_priv->lpe_audio.platdev = lpe_audio_platdev_create(dev_priv);
223 if (IS_ERR(dev_priv->lpe_audio.platdev)) {
224 ret = PTR_ERR(dev_priv->lpe_audio.platdev);
225 DRM_ERROR("Failed to create lpe audio platform device: %d\n",
226 ret);
227 goto err_free_irq;
230 /* enable chicken bit; at least this is required for Dell Wyse 3040
231 * with DP outputs (but only sometimes by some reason!)
233 I915_WRITE(VLV_AUD_CHICKEN_BIT_REG, VLV_CHICKEN_BIT_DBG_ENABLE);
235 return 0;
236 err_free_irq:
237 irq_free_desc(dev_priv->lpe_audio.irq);
238 err:
239 dev_priv->lpe_audio.irq = -1;
240 dev_priv->lpe_audio.platdev = NULL;
241 return ret;
245 * intel_lpe_audio_irq_handler() - forwards the LPE audio irq
246 * @dev_priv: the i915 drm device private data
248 * the LPE Audio irq is forwarded to the irq handler registered by LPE audio
249 * driver.
251 void intel_lpe_audio_irq_handler(struct drm_i915_private *dev_priv)
253 int ret;
255 if (!HAS_LPE_AUDIO(dev_priv))
256 return;
258 ret = generic_handle_irq(dev_priv->lpe_audio.irq);
259 if (ret)
260 DRM_ERROR_RATELIMITED("error handling LPE audio irq: %d\n",
261 ret);
265 * intel_lpe_audio_init() - detect and setup the bridge between HDMI LPE Audio
266 * driver and i915
267 * @dev_priv: the i915 drm device private data
269 * Return: 0 if successful. non-zero if detection or
270 * llocation/initialization fails
272 int intel_lpe_audio_init(struct drm_i915_private *dev_priv)
274 int ret = -ENODEV;
276 if (lpe_audio_detect(dev_priv)) {
277 ret = lpe_audio_setup(dev_priv);
278 if (ret < 0)
279 DRM_ERROR("failed to setup LPE Audio bridge\n");
281 return ret;
285 * intel_lpe_audio_teardown() - destroy the bridge between HDMI LPE
286 * audio driver and i915
287 * @dev_priv: the i915 drm device private data
289 * release all the resources for LPE audio <-> i915 bridge.
291 void intel_lpe_audio_teardown(struct drm_i915_private *dev_priv)
293 struct irq_desc *desc;
295 if (!HAS_LPE_AUDIO(dev_priv))
296 return;
298 desc = irq_to_desc(dev_priv->lpe_audio.irq);
300 lpe_audio_platdev_destroy(dev_priv);
302 irq_free_desc(dev_priv->lpe_audio.irq);
304 dev_priv->lpe_audio.irq = -1;
305 dev_priv->lpe_audio.platdev = NULL;
309 * intel_lpe_audio_notify() - notify lpe audio event
310 * audio driver and i915
311 * @dev_priv: the i915 drm device private data
312 * @pipe: pipe
313 * @port: port
314 * @eld : ELD data
315 * @ls_clock: Link symbol clock in kHz
316 * @dp_output: Driving a DP output?
318 * Notify lpe audio driver of eld change.
320 void intel_lpe_audio_notify(struct drm_i915_private *dev_priv,
321 enum pipe pipe, enum port port,
322 const void *eld, int ls_clock, bool dp_output)
324 unsigned long irqflags;
325 struct intel_hdmi_lpe_audio_pdata *pdata;
326 struct intel_hdmi_lpe_audio_port_pdata *ppdata;
327 u32 audio_enable;
329 if (!HAS_LPE_AUDIO(dev_priv))
330 return;
332 pdata = dev_get_platdata(&dev_priv->lpe_audio.platdev->dev);
333 ppdata = &pdata->port[port - PORT_B];
335 spin_lock_irqsave(&pdata->lpe_audio_slock, irqflags);
337 audio_enable = I915_READ(VLV_AUD_PORT_EN_DBG(port));
339 if (eld != NULL) {
340 memcpy(ppdata->eld, eld, HDMI_MAX_ELD_BYTES);
341 ppdata->pipe = pipe;
342 ppdata->ls_clock = ls_clock;
343 ppdata->dp_output = dp_output;
345 /* Unmute the amp for both DP and HDMI */
346 I915_WRITE(VLV_AUD_PORT_EN_DBG(port),
347 audio_enable & ~VLV_AMP_MUTE);
348 } else {
349 memset(ppdata->eld, 0, HDMI_MAX_ELD_BYTES);
350 ppdata->pipe = -1;
351 ppdata->ls_clock = 0;
352 ppdata->dp_output = false;
354 /* Mute the amp for both DP and HDMI */
355 I915_WRITE(VLV_AUD_PORT_EN_DBG(port),
356 audio_enable | VLV_AMP_MUTE);
359 if (pdata->notify_audio_lpe)
360 pdata->notify_audio_lpe(dev_priv->lpe_audio.platdev, port - PORT_B);
362 spin_unlock_irqrestore(&pdata->lpe_audio_slock, irqflags);