linux/sound/hda/hdac_component.c
Takashi Iwai 96e503f900 ALSA: hda/i915 - fix list corruption with concurrent probes
Current hdac_i915 uses a static completion instance to wait
for i915 driver to complete the component bind.

This design is not safe if multiple HDA controllers are active and
communicating with different i915 instances, and can lead to list
corruption and failed audio driver probe.

Fix the design by moving completion mechanism to common acomp
code and remove the related code from hdac_i915.

Fixes: 7b882fe3e3 ("ALSA: hda - handle multiple i915 device instances")
Co-developed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://lore.kernel.org/r/20201006161722.500256-1-kai.vehmanen@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-10-09 16:46:04 +02:00

355 lines
9.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
// hdac_component.c - routines for sync between HD-A core and DRM driver
#include <linux/init.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/component.h>
#include <sound/core.h>
#include <sound/hdaudio.h>
#include <sound/hda_component.h>
#include <sound/hda_register.h>
static void hdac_acomp_release(struct device *dev, void *res)
{
}
static struct drm_audio_component *hdac_get_acomp(struct device *dev)
{
return devres_find(dev, hdac_acomp_release, NULL, NULL);
}
/**
* snd_hdac_set_codec_wakeup - Enable / disable HDMI/DP codec wakeup
* @bus: HDA core bus
* @enable: enable or disable the wakeup
*
* This function is supposed to be used only by a HD-audio controller
* driver that needs the interaction with graphics driver.
*
* This function should be called during the chip reset, also called at
* resume for updating STATESTS register read.
*
* Returns zero for success or a negative error code.
*/
int snd_hdac_set_codec_wakeup(struct hdac_bus *bus, bool enable)
{
struct drm_audio_component *acomp = bus->audio_component;
if (!acomp || !acomp->ops)
return -ENODEV;
if (!acomp->ops->codec_wake_override)
return 0;
dev_dbg(bus->dev, "%s codec wakeup\n",
enable ? "enable" : "disable");
acomp->ops->codec_wake_override(acomp->dev, enable);
return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_set_codec_wakeup);
/**
* snd_hdac_display_power - Power up / down the power refcount
* @bus: HDA core bus
* @idx: HDA codec address, pass HDA_CODEC_IDX_CONTROLLER for controller
* @enable: power up or down
*
* This function is used by either HD-audio controller or codec driver that
* needs the interaction with graphics driver.
*
* This function updates the power status, and calls the get_power() and
* put_power() ops accordingly, toggling the codec wakeup, too.
*/
void snd_hdac_display_power(struct hdac_bus *bus, unsigned int idx, bool enable)
{
struct drm_audio_component *acomp = bus->audio_component;
dev_dbg(bus->dev, "display power %s\n",
enable ? "enable" : "disable");
mutex_lock(&bus->lock);
if (enable)
set_bit(idx, &bus->display_power_status);
else
clear_bit(idx, &bus->display_power_status);
if (!acomp || !acomp->ops)
goto unlock;
if (bus->display_power_status) {
if (!bus->display_power_active) {
unsigned long cookie = -1;
if (acomp->ops->get_power)
cookie = acomp->ops->get_power(acomp->dev);
snd_hdac_set_codec_wakeup(bus, true);
snd_hdac_set_codec_wakeup(bus, false);
bus->display_power_active = cookie;
}
} else {
if (bus->display_power_active) {
unsigned long cookie = bus->display_power_active;
if (acomp->ops->put_power)
acomp->ops->put_power(acomp->dev, cookie);
bus->display_power_active = 0;
}
}
unlock:
mutex_unlock(&bus->lock);
}
EXPORT_SYMBOL_GPL(snd_hdac_display_power);
/**
* snd_hdac_sync_audio_rate - Set N/CTS based on the sample rate
* @codec: HDA codec
* @nid: the pin widget NID
* @dev_id: device identifier
* @rate: the sample rate to set
*
* This function is supposed to be used only by a HD-audio controller
* driver that needs the interaction with graphics driver.
*
* This function sets N/CTS value based on the given sample rate.
* Returns zero for success, or a negative error code.
*/
int snd_hdac_sync_audio_rate(struct hdac_device *codec, hda_nid_t nid,
int dev_id, int rate)
{
struct hdac_bus *bus = codec->bus;
struct drm_audio_component *acomp = bus->audio_component;
int port, pipe;
if (!acomp || !acomp->ops || !acomp->ops->sync_audio_rate)
return -ENODEV;
port = nid;
if (acomp->audio_ops && acomp->audio_ops->pin2port) {
port = acomp->audio_ops->pin2port(codec, nid);
if (port < 0)
return -EINVAL;
}
pipe = dev_id;
return acomp->ops->sync_audio_rate(acomp->dev, port, pipe, rate);
}
EXPORT_SYMBOL_GPL(snd_hdac_sync_audio_rate);
/**
* snd_hdac_acomp_get_eld - Get the audio state and ELD via component
* @codec: HDA codec
* @nid: the pin widget NID
* @dev_id: device identifier
* @audio_enabled: the pointer to store the current audio state
* @buffer: the buffer pointer to store ELD bytes
* @max_bytes: the max bytes to be stored on @buffer
*
* This function is supposed to be used only by a HD-audio controller
* driver that needs the interaction with graphics driver.
*
* This function queries the current state of the audio on the given
* digital port and fetches the ELD bytes onto the given buffer.
* It returns the number of bytes for the total ELD data, zero for
* invalid ELD, or a negative error code.
*
* The return size is the total bytes required for the whole ELD bytes,
* thus it may be over @max_bytes. If it's over @max_bytes, it implies
* that only a part of ELD bytes have been fetched.
*/
int snd_hdac_acomp_get_eld(struct hdac_device *codec, hda_nid_t nid, int dev_id,
bool *audio_enabled, char *buffer, int max_bytes)
{
struct hdac_bus *bus = codec->bus;
struct drm_audio_component *acomp = bus->audio_component;
int port, pipe;
if (!acomp || !acomp->ops || !acomp->ops->get_eld)
return -ENODEV;
port = nid;
if (acomp->audio_ops && acomp->audio_ops->pin2port) {
port = acomp->audio_ops->pin2port(codec, nid);
if (port < 0)
return -EINVAL;
}
pipe = dev_id;
return acomp->ops->get_eld(acomp->dev, port, pipe, audio_enabled,
buffer, max_bytes);
}
EXPORT_SYMBOL_GPL(snd_hdac_acomp_get_eld);
static int hdac_component_master_bind(struct device *dev)
{
struct drm_audio_component *acomp = hdac_get_acomp(dev);
int ret;
if (WARN_ON(!acomp))
return -EINVAL;
ret = component_bind_all(dev, acomp);
if (ret < 0)
return ret;
if (WARN_ON(!(acomp->dev && acomp->ops))) {
ret = -EINVAL;
goto out_unbind;
}
/* pin the module to avoid dynamic unbinding, but only if given */
if (!try_module_get(acomp->ops->owner)) {
ret = -ENODEV;
goto out_unbind;
}
if (acomp->audio_ops && acomp->audio_ops->master_bind) {
ret = acomp->audio_ops->master_bind(dev, acomp);
if (ret < 0)
goto module_put;
}
complete_all(&acomp->master_bind_complete);
return 0;
module_put:
module_put(acomp->ops->owner);
out_unbind:
component_unbind_all(dev, acomp);
complete_all(&acomp->master_bind_complete);
return ret;
}
static void hdac_component_master_unbind(struct device *dev)
{
struct drm_audio_component *acomp = hdac_get_acomp(dev);
if (acomp->audio_ops && acomp->audio_ops->master_unbind)
acomp->audio_ops->master_unbind(dev, acomp);
module_put(acomp->ops->owner);
component_unbind_all(dev, acomp);
WARN_ON(acomp->ops || acomp->dev);
}
static const struct component_master_ops hdac_component_master_ops = {
.bind = hdac_component_master_bind,
.unbind = hdac_component_master_unbind,
};
/**
* snd_hdac_acomp_register_notifier - Register audio component ops
* @bus: HDA core bus
* @aops: audio component ops
*
* This function is supposed to be used only by a HD-audio controller
* driver that needs the interaction with graphics driver.
*
* This function sets the given ops to be called by the graphics driver.
*
* Returns zero for success or a negative error code.
*/
int snd_hdac_acomp_register_notifier(struct hdac_bus *bus,
const struct drm_audio_component_audio_ops *aops)
{
if (!bus->audio_component)
return -ENODEV;
bus->audio_component->audio_ops = aops;
return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_acomp_register_notifier);
/**
* snd_hdac_acomp_init - Initialize audio component
* @bus: HDA core bus
* @aops: audio component ops
* @match_master: match function for finding components
* @extra_size: Extra bytes to allocate
*
* This function is supposed to be used only by a HD-audio controller
* driver that needs the interaction with graphics driver.
*
* This function initializes and sets up the audio component to communicate
* with graphics driver.
*
* Unlike snd_hdac_i915_init(), this function doesn't synchronize with the
* binding with the DRM component. Each caller needs to sync via master_bind
* audio_ops.
*
* Returns zero for success or a negative error code.
*/
int snd_hdac_acomp_init(struct hdac_bus *bus,
const struct drm_audio_component_audio_ops *aops,
int (*match_master)(struct device *, int, void *),
size_t extra_size)
{
struct component_match *match = NULL;
struct device *dev = bus->dev;
struct drm_audio_component *acomp;
int ret;
if (WARN_ON(hdac_get_acomp(dev)))
return -EBUSY;
acomp = devres_alloc(hdac_acomp_release, sizeof(*acomp) + extra_size,
GFP_KERNEL);
if (!acomp)
return -ENOMEM;
acomp->audio_ops = aops;
init_completion(&acomp->master_bind_complete);
bus->audio_component = acomp;
devres_add(dev, acomp);
component_match_add_typed(dev, &match, match_master, bus);
ret = component_master_add_with_match(dev, &hdac_component_master_ops,
match);
if (ret < 0)
goto out_err;
return 0;
out_err:
bus->audio_component = NULL;
devres_destroy(dev, hdac_acomp_release, NULL, NULL);
dev_info(dev, "failed to add audio component master (%d)\n", ret);
return ret;
}
EXPORT_SYMBOL_GPL(snd_hdac_acomp_init);
/**
* snd_hdac_acomp_exit - Finalize audio component
* @bus: HDA core bus
*
* This function is supposed to be used only by a HD-audio controller
* driver that needs the interaction with graphics driver.
*
* This function releases the audio component that has been used.
*
* Returns zero for success or a negative error code.
*/
int snd_hdac_acomp_exit(struct hdac_bus *bus)
{
struct device *dev = bus->dev;
struct drm_audio_component *acomp = bus->audio_component;
if (!acomp)
return 0;
if (WARN_ON(bus->display_power_active) && acomp->ops)
acomp->ops->put_power(acomp->dev, bus->display_power_active);
bus->display_power_active = 0;
bus->display_power_status = 0;
component_master_del(dev, &hdac_component_master_ops);
bus->audio_component = NULL;
devres_destroy(dev, hdac_acomp_release, NULL, NULL);
return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_acomp_exit);