--- /dev/null
+/*
+ * 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);
Code Review / kvmfornfv.git / blobdiff