[PATCH v5 2/4] ALSA: hda/realtek: Support ACPI Notification framework via component binding

From: Stefan Binding
Date: Thu Sep 21 2023 - 17:07:48 EST


For systems which have support for ACPI notifications, add a mechanism to
register a handler for ACPI notifications and then call the acpi_notify
api on the bound components.

Registering a handler in the Realtek HDA driver, allows a single handler to
be registered, which then calls into all the components, rather than
attempting to register the same handler multiple times, once for each
component.

Signed-off-by: Stefan Binding <sbinding@xxxxxxxxxxxxxxxxxxxxx>
---
sound/pci/hda/patch_realtek.c | 83 ++++++++++++++++++++++++++++++++++-
1 file changed, 82 insertions(+), 1 deletion(-)

diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c
index 883a7e865bc5..1e2b6a299dbc 100644
--- a/sound/pci/hda/patch_realtek.c
+++ b/sound/pci/hda/patch_realtek.c
@@ -10,6 +10,7 @@
* Jonathan Woithe <jwoithe@xxxxxxxxxx>
*/

+#include <linux/acpi.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/slab.h>
@@ -6704,12 +6705,91 @@ static void alc287_fixup_legion_15imhg05_speakers(struct hda_codec *codec,
}
}

+#ifdef CONFIG_ACPI
+static void comp_acpi_device_notify(acpi_handle handle, u32 event, void *data)
+{
+ struct hda_codec *cdc = data;
+ struct alc_spec *spec = cdc->spec;
+ int i;
+
+ codec_info(cdc, "ACPI Notification %d\n", event);
+
+ for (i = 0; i < HDA_MAX_COMPONENTS; i++) {
+ if (spec->comps[i].dev && spec->comps[i].acpi_notify)
+ spec->comps[i].acpi_notify(acpi_device_handle(spec->comps[i].adev), event,
+ spec->comps[i].dev);
+ }
+}
+
+static int comp_bind_acpi(struct device *dev)
+{
+ struct hda_codec *cdc = dev_to_hda_codec(dev);
+ struct alc_spec *spec = cdc->spec;
+ bool support_notifications = false;
+ struct acpi_device *adev;
+ int ret;
+ int i;
+
+ adev = spec->comps[0].adev;
+ if (!acpi_device_handle(adev))
+ return 0;
+
+ for (i = 0; i < HDA_MAX_COMPONENTS; i++)
+ support_notifications = support_notifications ||
+ spec->comps[i].acpi_notifications_supported;
+
+ if (support_notifications) {
+ ret = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
+ comp_acpi_device_notify, cdc);
+ if (ret < 0) {
+ codec_warn(cdc, "Failed to install notify handler: %d\n", ret);
+ return 0;
+ }
+
+ codec_dbg(cdc, "Notify handler installed\n");
+ }
+
+ return 0;
+}
+
+static void comp_unbind_acpi(struct device *dev)
+{
+ struct hda_codec *cdc = dev_to_hda_codec(dev);
+ struct alc_spec *spec = cdc->spec;
+ struct acpi_device *adev;
+ int ret;
+
+ adev = spec->comps[0].adev;
+ if (!acpi_device_handle(adev))
+ return;
+
+ ret = acpi_remove_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
+ comp_acpi_device_notify);
+ if (ret < 0)
+ codec_warn(cdc, "Failed to uninstall notify handler: %d\n", ret);
+}
+#else
+static int comp_bind_acpi(struct device *dev)
+{
+ return 0;
+}
+
+static void comp_unbind_acpi(struct device *dev)
+{
+}
+#endif
+
static int comp_bind(struct device *dev)
{
struct hda_codec *cdc = dev_to_hda_codec(dev);
struct alc_spec *spec = cdc->spec;
+ int ret;
+
+ ret = component_bind_all(dev, spec->comps);
+ if (ret)
+ return ret;

- return component_bind_all(dev, spec->comps);
+ return comp_bind_acpi(dev);
}

static void comp_unbind(struct device *dev)
@@ -6717,6 +6797,7 @@ static void comp_unbind(struct device *dev)
struct hda_codec *cdc = dev_to_hda_codec(dev);
struct alc_spec *spec = cdc->spec;

+ comp_unbind_acpi(dev);
component_unbind_all(dev, spec->comps);
}

--
2.34.1