1 files changed, 279 insertions, 0 deletions

diff --git a/kernel/sound/hda/hdac_i915.c b/kernel/sound/hda/hdac_i915.c
new file mode 100644
index 000000000..8fef1b8d1
--- /dev/null
+++ b/kernel/sound/hda/hdac_i915.c
@@ -0,0 +1,279 @@
+/*
+ *  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);
+
+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_err(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);