--- /dev/null
+/*
+ * Copyright © 2016 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ * Authors:
+ * Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
+ * Jerome Anand <jerome.anand@intel.com>
+ * based on VED patches
+ *
+ */
+
+/**
+ * DOC: LPE Audio integration for HDMI or DP playback
+ *
+ * Motivation:
+ * Atom platforms (e.g. valleyview and cherryTrail) integrates a DMA-based
+ * interface as an alternative to the traditional HDaudio path. While this
+ * mode is unrelated to the LPE aka SST audio engine, the documentation refers
+ * to this mode as LPE so we keep this notation for the sake of consistency.
+ *
+ * The interface is handled by a separate standalone driver maintained in the
+ * ALSA subsystem for simplicity. To minimize the interaction between the two
+ * subsystems, a bridge is setup between the hdmi-lpe-audio and i915:
+ * 1. Create a platform device to share MMIO/IRQ resources
+ * 2. Make the platform device child of i915 device for runtime PM.
+ * 3. Create IRQ chip to forward the LPE audio irqs.
+ * the hdmi-lpe-audio driver probes the lpe audio device and creates a new
+ * sound card
+ *
+ * Threats:
+ * Due to the restriction in Linux platform device model, user need manually
+ * uninstall the hdmi-lpe-audio driver before uninstalling i915 module,
+ * otherwise we might run into use-after-free issues after i915 removes the
+ * platform device: even though hdmi-lpe-audio driver is released, the modules
+ * is still in "installed" status.
+ *
+ * Implementation:
+ * The MMIO/REG platform resources are created according to the registers
+ * specification.
+ * When forwarding LPE audio irqs, the flow control handler selection depends
+ * on the platform, for example on valleyview handle_simple_irq is enough.
+ *
+ */
+
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/pci.h>
+
+#include "i915_drv.h"
+#include <linux/delay.h>
+#include <drm/intel_lpe_audio.h>
+
+#define HAS_LPE_AUDIO(dev_priv) ((dev_priv)->lpe_audio.platdev != NULL)
+
+static struct platform_device *
+lpe_audio_platdev_create(struct drm_i915_private *dev_priv)
+{
+ int ret;
+ struct drm_device *dev = &dev_priv->drm;
+ struct platform_device_info pinfo = {};
+ struct resource *rsc;
+ struct platform_device *platdev;
+ struct intel_hdmi_lpe_audio_pdata *pdata;
+
+ pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return ERR_PTR(-ENOMEM);
+
+ rsc = kcalloc(2, sizeof(*rsc), GFP_KERNEL);
+ if (!rsc) {
+ kfree(pdata);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ rsc[0].start = rsc[0].end = dev_priv->lpe_audio.irq;
+ rsc[0].flags = IORESOURCE_IRQ;
+ rsc[0].name = "hdmi-lpe-audio-irq";
+
+ rsc[1].start = pci_resource_start(dev->pdev, 0) +
+ I915_HDMI_LPE_AUDIO_BASE;
+ rsc[1].end = pci_resource_start(dev->pdev, 0) +
+ I915_HDMI_LPE_AUDIO_BASE + I915_HDMI_LPE_AUDIO_SIZE - 1;
+ rsc[1].flags = IORESOURCE_MEM;
+ rsc[1].name = "hdmi-lpe-audio-mmio";
+
+ pinfo.parent = dev->dev;
+ pinfo.name = "hdmi-lpe-audio";
+ pinfo.id = -1;
+ pinfo.res = rsc;
+ pinfo.num_res = 2;
+ pinfo.data = pdata;
+ pinfo.size_data = sizeof(*pdata);
+ pinfo.dma_mask = DMA_BIT_MASK(32);
+
+ spin_lock_init(&pdata->lpe_audio_slock);
+
+ platdev = platform_device_register_full(&pinfo);
+ if (IS_ERR(platdev)) {
+ ret = PTR_ERR(platdev);
+ DRM_ERROR("Failed to allocate LPE audio platform device\n");
+ goto err;
+ }
+
+ kfree(rsc);
+
+ return platdev;
+
+err:
+ kfree(rsc);
+ kfree(pdata);
+ return ERR_PTR(ret);
+}
+
+static void lpe_audio_platdev_destroy(struct drm_i915_private *dev_priv)
+{
+ platform_device_unregister(dev_priv->lpe_audio.platdev);
+ kfree(dev_priv->lpe_audio.platdev->dev.dma_mask);
+}
+
+static void lpe_audio_irq_unmask(struct irq_data *d)
+{
+ struct drm_i915_private *dev_priv = d->chip_data;
+ unsigned long irqflags;
+ u32 val = (I915_LPE_PIPE_A_INTERRUPT |
+ I915_LPE_PIPE_B_INTERRUPT);
+
+ if (IS_CHERRYVIEW(dev_priv))
+ val |= I915_LPE_PIPE_C_INTERRUPT;
+
+ spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
+
+ dev_priv->irq_mask &= ~val;
+ I915_WRITE(VLV_IIR, val);
+ I915_WRITE(VLV_IIR, val);
+ I915_WRITE(VLV_IMR, dev_priv->irq_mask);
+ POSTING_READ(VLV_IMR);
+
+ spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
+}
+
+static void lpe_audio_irq_mask(struct irq_data *d)
+{
+ struct drm_i915_private *dev_priv = d->chip_data;
+ unsigned long irqflags;
+ u32 val = (I915_LPE_PIPE_A_INTERRUPT |
+ I915_LPE_PIPE_B_INTERRUPT);
+
+ if (IS_CHERRYVIEW(dev_priv))
+ val |= I915_LPE_PIPE_C_INTERRUPT;
+
+ spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
+
+ dev_priv->irq_mask |= val;
+ I915_WRITE(VLV_IMR, dev_priv->irq_mask);
+ I915_WRITE(VLV_IIR, val);
+ I915_WRITE(VLV_IIR, val);
+ POSTING_READ(VLV_IIR);
+
+ spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
+}
+
+static struct irq_chip lpe_audio_irqchip = {
+ .name = "hdmi_lpe_audio_irqchip",
+ .irq_mask = lpe_audio_irq_mask,
+ .irq_unmask = lpe_audio_irq_unmask,
+};
+
+static int lpe_audio_irq_init(struct drm_i915_private *dev_priv)
+{
+ int irq = dev_priv->lpe_audio.irq;
+
+ WARN_ON(!intel_irqs_enabled(dev_priv));
+ irq_set_chip_and_handler_name(irq,
+ &lpe_audio_irqchip,
+ handle_simple_irq,
+ "hdmi_lpe_audio_irq_handler");
+
+ return irq_set_chip_data(irq, dev_priv);
+}
+
+static bool lpe_audio_detect(struct drm_i915_private *dev_priv)
+{
+ int lpe_present = false;
+
+ if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
+ static const struct pci_device_id atom_hdaudio_ids[] = {
+ /* Baytrail */
+ {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0f04)},
+ /* Braswell */
+ {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2284)},
+ {}
+ };
+
+ if (!pci_dev_present(atom_hdaudio_ids)) {
+ DRM_INFO("%s\n", "HDaudio controller not detected, using LPE audio instead\n");
+ lpe_present = true;
+ }
+ }
+ return lpe_present;
+}
+
+static int lpe_audio_setup(struct drm_i915_private *dev_priv)
+{
+ int ret;
+
+ dev_priv->lpe_audio.irq = irq_alloc_desc(0);
+ if (dev_priv->lpe_audio.irq < 0) {
+ DRM_ERROR("Failed to allocate IRQ desc: %d\n",
+ dev_priv->lpe_audio.irq);
+ ret = dev_priv->lpe_audio.irq;
+ goto err;
+ }
+
+ DRM_DEBUG("irq = %d\n", dev_priv->lpe_audio.irq);
+
+ ret = lpe_audio_irq_init(dev_priv);
+
+ if (ret) {
+ DRM_ERROR("Failed to initialize irqchip for lpe audio: %d\n",
+ ret);
+ goto err_free_irq;
+ }
+
+ dev_priv->lpe_audio.platdev = lpe_audio_platdev_create(dev_priv);
+
+ if (IS_ERR(dev_priv->lpe_audio.platdev)) {
+ ret = PTR_ERR(dev_priv->lpe_audio.platdev);
+ DRM_ERROR("Failed to create lpe audio platform device: %d\n",
+ ret);
+ goto err_free_irq;
+ }
+
+ return 0;
+err_free_irq:
+ irq_free_desc(dev_priv->lpe_audio.irq);
+err:
+ dev_priv->lpe_audio.irq = -1;
+ dev_priv->lpe_audio.platdev = NULL;
+ return ret;
+}
+
+/**
+ * intel_lpe_audio_irq_handler() - forwards the LPE audio irq
+ * @dev_priv: the i915 drm device private data
+ *
+ * the LPE Audio irq is forwarded to the irq handler registered by LPE audio
+ * driver.
+ */
+void intel_lpe_audio_irq_handler(struct drm_i915_private *dev_priv)
+{
+ int ret;
+
+ if (!HAS_LPE_AUDIO(dev_priv))
+ return;
+
+ ret = generic_handle_irq(dev_priv->lpe_audio.irq);
+ if (ret)
+ DRM_ERROR_RATELIMITED("error handling LPE audio irq: %d\n",
+ ret);
+}
+
+/**
+ * intel_lpe_audio_init() - detect and setup the bridge between HDMI LPE Audio
+ * driver and i915
+ * @dev_priv: the i915 drm device private data
+ *
+ * Return: 0 if successful. non-zero if detection or
+ * llocation/initialization fails
+ */
+int intel_lpe_audio_init(struct drm_i915_private *dev_priv)
+{
+ int ret = -ENODEV;
+
+ if (lpe_audio_detect(dev_priv)) {
+ ret = lpe_audio_setup(dev_priv);
+ if (ret < 0)
+ DRM_ERROR("failed to setup LPE Audio bridge\n");
+ }
+ return ret;
+}
+
+/**
+ * intel_lpe_audio_teardown() - destroy the bridge between HDMI LPE
+ * audio driver and i915
+ * @dev_priv: the i915 drm device private data
+ *
+ * release all the resources for LPE audio <-> i915 bridge.
+ */
+void intel_lpe_audio_teardown(struct drm_i915_private *dev_priv)
+{
+ struct irq_desc *desc;
+
+ if (!HAS_LPE_AUDIO(dev_priv))
+ return;
+
+ desc = irq_to_desc(dev_priv->lpe_audio.irq);
+
+ lpe_audio_irq_mask(&desc->irq_data);
+
+ lpe_audio_platdev_destroy(dev_priv);
+
+ irq_free_desc(dev_priv->lpe_audio.irq);
+}
--- /dev/null
+/*
+ * Copyright © 2016 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef _INTEL_LPE_AUDIO_H_
+#define _INTEL_LPE_AUDIO_H_
+
+#include <linux/types.h>
+#include <linux/spinlock_types.h>
+
+#define HDMI_MAX_ELD_BYTES 128
+
+struct intel_hdmi_lpe_audio_eld {
+ int port_id;
+ unsigned char eld_data[HDMI_MAX_ELD_BYTES];
+};
+
+struct intel_hdmi_lpe_audio_pdata {
+ bool notify_pending;
+ int tmds_clock_speed;
+ bool hdmi_connected;
+ struct intel_hdmi_lpe_audio_eld eld;
+ void (*notify_audio_lpe)(void *audio_ptr);
+ spinlock_t lpe_audio_slock;
+};
+
+#endif /* _I915_LPE_AUDIO_H_ */
projects / mirror_ubuntu-artful-kernel.git / commitdiff