/*
* 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 <[email protected]>
* Jerome Anand <[email protected]>
* 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/delay.h>
#include <linux/device.h>
#include <linux/irq.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <drm/intel/intel_lpe_audio.h>
#include "i915_drv.h"
#include "i915_irq.h"
#include "intel_audio_regs.h"
#include "intel_de.h"
#include "intel_lpe_audio.h"
#include "intel_pci_config.h"
#define HAS_LPE_AUDIO(dev_priv) ((dev_priv)->display.audio.lpe.platdev != NULL)
static struct platform_device *
lpe_audio_platdev_create(struct drm_i915_private *dev_priv)
{
struct pci_dev *pdev = to_pci_dev(dev_priv->drm.dev);
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->display.audio.lpe.irq;
rsc[0].flags = IORESOURCE_IRQ;
rsc[0].name = "hdmi-lpe-audio-irq";
rsc[1].start = pci_resource_start(pdev, GEN4_GTTMMADR_BAR) +
I915_HDMI_LPE_AUDIO_BASE;
rsc[1].end = pci_resource_start(pdev, GEN4_GTTMMADR_BAR) +
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_priv->drm.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);
pdata->num_pipes = INTEL_NUM_PIPES(dev_priv);
pdata->num_ports = IS_CHERRYVIEW(dev_priv) ? 3 : 2; /* B,C,D or B,C */
pdata->port[0].pipe = -1;
pdata->port[1].pipe = -1;
pdata->port[2].pipe = -1;
spin_lock_init(&pdata->lpe_audio_slock);
platdev = platform_device_register_full(&pinfo);
kfree(rsc);
kfree(pdata);
if (IS_ERR(platdev)) {
drm_err(&dev_priv->drm,
"Failed to allocate LPE audio platform device\n");
return platdev;
}
pm_runtime_no_callbacks(&platdev->dev);
return platdev;
}
static void lpe_audio_platdev_destroy(struct drm_i915_private *dev_priv)
{
/* XXX Note that platform_device_register_full() allocates a dma_mask
* and never frees it. We can't free it here as we cannot guarantee
* this is the last reference (i.e. that the dma_mask will not be
* used after our unregister). So ee choose to leak the sizeof(u64)
* allocation here - it should be fixed in the platform_device rather
* than us fiddle with its internals.
*/
platform_device_unregister(dev_priv->display.audio.lpe.platdev);
}
static void lpe_audio_irq_unmask(struct irq_data *d)
{
}
static void lpe_audio_irq_mask(struct irq_data *d)
{
}
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->display.audio.lpe.irq;
drm_WARN_ON(&dev_priv->drm, !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(&dev_priv->drm,
"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->display.audio.lpe.irq = irq_alloc_desc(0);
if (dev_priv->display.audio.lpe.irq < 0) {
drm_err(&dev_priv->drm, "Failed to allocate IRQ desc: %d\n",
dev_priv->display.audio.lpe.irq);
ret = dev_priv->display.audio.lpe.irq;
goto err;
}
drm_dbg(&dev_priv->drm, "irq = %d\n", dev_priv->display.audio.lpe.irq);
ret = lpe_audio_irq_init(dev_priv);
if (ret) {
drm_err(&dev_priv->drm,
"Failed to initialize irqchip for lpe audio: %d\n",
ret);
goto err_free_irq;
}
dev_priv->display.audio.lpe.platdev = lpe_audio_platdev_create(dev_priv);
if (IS_ERR(dev_priv->display.audio.lpe.platdev)) {
ret = PTR_ERR(dev_priv->display.audio.lpe.platdev);
drm_err(&dev_priv->drm,
"Failed to create lpe audio platform device: %d\n",
ret);
goto err_free_irq;
}
/* enable chicken bit; at least this is required for Dell Wyse 3040
* with DP outputs (but only sometimes by some reason!)
*/
intel_de_write(dev_priv, VLV_AUD_CHICKEN_BIT_REG,
VLV_CHICKEN_BIT_DBG_ENABLE);
return 0;
err_free_irq:
irq_free_desc(dev_priv->display.audio.lpe.irq);
err:
dev_priv->display.audio.lpe.irq = -1;
dev_priv->display.audio.lpe.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->display.audio.lpe.irq);
if (ret)
drm_err_ratelimited(&dev_priv->drm,
"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_err(&dev_priv->drm,
"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)
{
if (!HAS_LPE_AUDIO(dev_priv))
return;
lpe_audio_platdev_destroy(dev_priv);
irq_free_desc(dev_priv->display.audio.lpe.irq);
dev_priv->display.audio.lpe.irq = -1;
dev_priv->display.audio.lpe.platdev = NULL;
}
/**
* intel_lpe_audio_notify() - notify lpe audio event
* audio driver and i915
* @dev_priv: the i915 drm device private data
* @cpu_transcoder: CPU transcoder
* @port: port
* @eld : ELD data
* @ls_clock: Link symbol clock in kHz
* @dp_output: Driving a DP output?
*
* Notify lpe audio driver of eld change.
*/
void intel_lpe_audio_notify(struct drm_i915_private *dev_priv,
enum transcoder cpu_transcoder, enum port port,
const void *eld, int ls_clock, bool dp_output)
{
unsigned long irqflags;
struct intel_hdmi_lpe_audio_pdata *pdata;
struct intel_hdmi_lpe_audio_port_pdata *ppdata;
u32 audio_enable;
if (!HAS_LPE_AUDIO(dev_priv))
return;
pdata = dev_get_platdata(&dev_priv->display.audio.lpe.platdev->dev);
ppdata = &pdata->port[port - PORT_B];
spin_lock_irqsave(&pdata->lpe_audio_slock, irqflags);
audio_enable = intel_de_read(dev_priv, VLV_AUD_PORT_EN_DBG(port));
if (eld != NULL) {
memcpy(ppdata->eld, eld, HDMI_MAX_ELD_BYTES);
ppdata->pipe = cpu_transcoder;
ppdata->ls_clock = ls_clock;
ppdata->dp_output = dp_output;
/* Unmute the amp for both DP and HDMI */
intel_de_write(dev_priv, VLV_AUD_PORT_EN_DBG(port),
audio_enable & ~VLV_AMP_MUTE);
} else {
memset(ppdata->eld, 0, HDMI_MAX_ELD_BYTES);
ppdata->pipe = -1;
ppdata->ls_clock = 0;
ppdata->dp_output = false;
/* Mute the amp for both DP and HDMI */
intel_de_write(dev_priv, VLV_AUD_PORT_EN_DBG(port),
audio_enable | VLV_AMP_MUTE);
}
if (pdata->notify_audio_lpe)
pdata->notify_audio_lpe(dev_priv->display.audio.lpe.platdev, port - PORT_B);
spin_unlock_irqrestore(&pdata->lpe_audio_slock, irqflags);
}
Codebase Browser
linux