/*
* hdac_i915.c - routines for sync between HD-A core and i915 display driver
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/component.h>
#include <drm/i915_component.h>
#include <sound/core.h>
#include <sound/hdaudio.h>
#include <sound/hda_i915.h>
static struct i915_audio_component *hdac_acomp;
/**
* 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 i915 graphics.
*
* 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 i915_audio_component *acomp = bus->audio_component;
if (!acomp || !acomp->ops)
return -ENODEV;
if (!acomp->ops->codec_wake_override) {
dev_warn(bus->dev,
"Invalid codec wake callback\n");
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
* @enable: power up or down
*
* This function is supposed to be used only by a HD-audio controller
* driver that needs the interaction with i915 graphics.
*
* This function manages a refcount and calls the i915 get_power() and
* put_power() ops accordingly, toggling the codec wakeup, too.
*
* Returns zero for success or a negative error code.
*/
int snd_hdac_display_power(struct hdac_bus *bus, bool enable)
{
struct i915_audio_component *acomp = bus->audio_component;
if (!acomp || !acomp->ops)
return -ENODEV;
dev_dbg(bus->dev, "display power %s\n",
enable ? "enable" : "disable");
if (enable) {
if (!bus->i915_power_refcount++) {
acomp->ops->get_power(acomp->dev);
snd_hdac_set_codec_wakeup(bus, true);
snd_hdac_set_codec_wakeup(bus, false);
}
} else {
WARN_ON(!bus->i915_power_refcount);
if (!--bus->i915_power_refcount)
acomp->ops->put_power(acomp->dev);
}
return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_display_power);
/**
* snd_hdac_get_display_clk - Get CDCLK in kHz
* @bus: HDA core bus
*
* This function is supposed to be used only by a HD-audio controller
* driver that needs the interaction with i915 graphics.
*
* This function queries CDCLK value in kHz from the graphics driver and
* returns the value. A negative code is returned in error.
*/
int snd_hdac_get_display_clk(struct hdac_bus *bus)
{
struct i915_audio_component *acomp = bus->audio_component;
if (!acomp || !acomp->ops)
return -ENODEV;
return acomp->ops->get_cdclk_freq(acomp->dev);
}
EXPORT_SYMBOL_GPL(snd_hdac_get_display_clk);
/* There is a fixed mapping between audio pin node and display port
* on current Intel platforms:
* Pin Widget 5 - PORT B (port = 1 in i915 driver)
* Pin Widget 6 - PORT C (port = 2 in i915 driver)
* Pin Widget 7 - PORT D (port = 3 in i915 driver)
*/
static int pin2port(hda_nid_t pin_nid)
{
if (WARN_ON(pin_nid < 5 || pin_nid > 7))
return -1;
return pin_nid - 4;
}
/**
* snd_hdac_sync_audio_rate - Set N/CTS based on the sample rate
* @bus: HDA core bus
* @nid: the pin widget NID
* @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 i915 graphics.
*
* 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_bus *bus, hda_nid_t nid, int rate)
{
struct i915_audio_component *acomp = bus->audio_component;
int port;
if (!acomp || !acomp->ops || !acomp->ops->sync_audio_rate)
return -ENODEV;
port = pin2port(nid);
if (port < 0)
return -EINVAL;
return acomp->ops->sync_audio_rate(acomp->dev, port, rate);
}
EXPORT_SYMBOL_GPL(snd_hdac_sync_audio_rate);
/**
* snd_hdac_acomp_get_eld - Get the audio state and ELD via component
* @bus: HDA core bus
* @nid: the pin widget NID
* @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 i915 graphics.
*
* 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_bus *bus, hda_nid_t nid,
bool *audio_enabled, char *buffer, int max_bytes)
{
struct i915_audio_component *acomp = bus->audio_component;
int port;
if (!acomp || !acomp->ops || !acomp->ops->get_eld)
return -ENODEV;
port = pin2port(nid);
if (port < 0)
return -EINVAL;
return acomp->ops->get_eld(acomp->dev, port, audio_enabled,
buffer, max_bytes);
}
EXPORT_SYMBOL_GPL(snd_hdac_acomp_get_eld);
static int hdac_component_master_bind(struct device *dev)
{
struct i915_audio_component *acomp = hdac_acomp;
int ret;
ret = component_bind_all(dev, acomp);
if (ret < 0)
return ret;
if (WARN_ON(!(acomp->dev && acomp->ops && acomp->ops->get_power &&
acomp->ops->put_power && acomp->ops->get_cdclk_freq))) {
ret = -EINVAL;
goto out_unbind;
}
/*
* Atm, we don't support dynamic unbinding initiated by the child
* component, so pin its containing module until we unbind.
*/
if (!try_module_get(acomp->ops->owner)) {
ret = -ENODEV;
goto out_unbind;
}
return 0;
out_unbind:
component_unbind_all(dev, acomp);
return ret;
}
static void hdac_component_master_unbind(struct device *dev)
{
struct i915_audio_component *acomp = hdac_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,
};
static int hdac_component_master_match(struct device *dev, void *data)
{
/* i915 is the only supported component */
return !strcmp(dev->driver->name, "i915");
}
/**
* snd_hdac_i915_register_notifier - Register i915 audio component ops
* @aops: i915 audio component ops
*
* This function is supposed to be used only by a HD-audio controller
* driver that needs the interaction with i915 graphics.
*
* This function sets the given ops to be called by the i915 graphics driver.
*
* Returns zero for success or a negative error code.
*/
int snd_hdac_i915_register_notifier(const struct i915_audio_component_audio_ops *aops)
{
if (WARN_ON(!hdac_acomp))
return -ENODEV;
hdac_acomp->audio_ops = aops;
return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_i915_register_notifier);
/**
* snd_hdac_i915_init - Initialize i915 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 i915 graphics.
*
* This function initializes and sets up the audio component to communicate
* with i915 graphics driver.
*
* Returns zero for success or a negative error code.
*/
int snd_hdac_i915_init(struct hdac_bus *bus)
{
struct component_match *match = NULL;
struct device *dev = bus->dev;
struct i915_audio_component *acomp;
int ret;
acomp = kzalloc(sizeof(*acomp), GFP_KERNEL);
if (!acomp)
return -ENOMEM;
bus->audio_component = acomp;
hdac_acomp = acomp;
component_match_add(dev, &match, hdac_component_master_match, bus);
ret = component_master_add_with_match(dev, &hdac_component_master_ops,
match);
if (ret < 0)
goto out_err;
/*
* Atm, we don't support deferring the component binding, so make sure
* i915 is loaded and that the binding successfully completes.
*/
request_module("i915");
if (!acomp->ops) {
ret = -ENODEV;
goto out_master_del;
}
dev_dbg(dev, "bound to i915 component master\n");
return 0;
out_master_del:
component_master_del(dev, &hdac_component_master_ops);
out_err:
kfree(acomp);
bus->audio_component = NULL;
dev_info(dev, "failed to add i915 component master (%d)\n", ret);
return ret;
}
EXPORT_SYMBOL_GPL(snd_hdac_i915_init);
/**
* snd_hdac_i915_exit - Finalize i915 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 i915 graphics.
*
* This function releases the i915 audio component that has been used.
*
* Returns zero for success or a negative error code.
*/
int snd_hdac_i915_exit(struct hdac_bus *bus)
{
struct device *dev = bus->dev;
struct i915_audio_component *acomp = bus->audio_component;
if (!acomp)
return 0;
WARN_ON(bus->i915_power_refcount);
if (bus->i915_power_refcount > 0 && acomp->ops)
acomp->ops->put_power(acomp->dev);
component_master_del(dev, &hdac_component_master_ops);
kfree(acomp);
bus->audio_component = NULL;
return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_i915_exit);
