From 4c6a161a06aa82e0af6a49db20813d07488af2ee Mon Sep 17 00:00:00 2001
From: XiNGRZ <hi@xingrz.me>
Date: Sun, 15 Jan 2023 00:07:04 +0800
Subject: [PATCH] dynamic: Do power management on Knob

---
 .../arm/hw75_dynamic/app/CMakeLists.txt       |  3 +
 config/boards/arm/hw75_dynamic/app/knob_app.c | 62 +++++++++++++++++++
 config/drivers/sensor/knob/lib/knob.c         | 10 +--
 3 files changed, 67 insertions(+), 8 deletions(-)
 create mode 100644 config/boards/arm/hw75_dynamic/app/knob_app.c

diff --git a/config/boards/arm/hw75_dynamic/app/CMakeLists.txt b/config/boards/arm/hw75_dynamic/app/CMakeLists.txt
index 27619911..2a8211c5 100644
--- a/config/boards/arm/hw75_dynamic/app/CMakeLists.txt
+++ b/config/boards/arm/hw75_dynamic/app/CMakeLists.txt
@@ -9,3 +9,6 @@ zephyr_library_include_directories(${ZEPHYR_BASE}/lib/gui/lvgl)
 zephyr_library_include_directories(${CMAKE_SOURCE_DIR}/include)
 zephyr_library_sources_ifdef(CONFIG_ZMK_DISPLAY_STATUS_SCREEN_CUSTOM status_screen.c)
 zephyr_library_sources_ifdef(CONFIG_ZMK_DISPLAY_STATUS_SCREEN_CUSTOM widgets/layer_status.c)
+
+zephyr_library_include_directories_ifdef(CONFIG_KNOB ${ZMK_CONFIG}/drivers/sensor/knob/include)
+zephyr_library_sources_ifdef(CONFIG_KNOB knob_app.c)
diff --git a/config/boards/arm/hw75_dynamic/app/knob_app.c b/config/boards/arm/hw75_dynamic/app/knob_app.c
new file mode 100644
index 00000000..6409eeec
--- /dev/null
+++ b/config/boards/arm/hw75_dynamic/app/knob_app.c
@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2022-2023 XiNGRZ
+ * SPDX-License-Identifier: MIT
+ */
+
+#include <kernel.h>
+#include <device.h>
+
+#include <logging/log.h>
+LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
+
+#include <knob/drivers/knob.h>
+
+#include <zmk/activity.h>
+#include <zmk/usb.h>
+#include <zmk/event_manager.h>
+#include <zmk/events/activity_state_changed.h>
+#include <zmk/events/usb_conn_state_changed.h>
+
+static const struct device *knob;
+
+static int knob_app_init(const struct device *dev)
+{
+	ARG_UNUSED(dev);
+
+	knob = device_get_binding("KNOB");
+	if (knob) {
+		LOG_INF("Found Knob device");
+	} else {
+		LOG_ERR("Knob device not found");
+		return -EINVAL;
+	}
+
+	knob_set_mode(knob, KNOB_ENCODER);
+	knob_set_encoder_report(knob, true);
+
+	return 0;
+}
+
+static int knob_app_event_listener(const zmk_event_t *eh)
+{
+	bool active, hid_ready;
+
+	if (!knob) {
+		return -ENODEV;
+	}
+
+	if (as_zmk_activity_state_changed(eh) || as_zmk_usb_conn_state_changed(eh)) {
+		active = zmk_activity_get_state() == ZMK_ACTIVITY_ACTIVE;
+		hid_ready = zmk_usb_is_hid_ready();
+		knob_set_enable(knob, active && hid_ready);
+		return 0;
+	}
+
+	return -ENOTSUP;
+}
+
+ZMK_LISTENER(knob_app, knob_app_event_listener);
+ZMK_SUBSCRIPTION(knob_app, zmk_activity_state_changed);
+ZMK_SUBSCRIPTION(knob_app, zmk_usb_conn_state_changed);
+
+SYS_INIT(knob_app_init, APPLICATION, CONFIG_APPLICATION_INIT_PRIORITY);
diff --git a/config/drivers/sensor/knob/lib/knob.c b/config/drivers/sensor/knob/lib/knob.c
index c3d3ab23..a3bf2ce7 100644
--- a/config/drivers/sensor/knob/lib/knob.c
+++ b/config/drivers/sensor/knob/lib/knob.c
@@ -190,7 +190,7 @@ void knob_set_mode(const struct device *dev, enum knob_mode mode)
 void knob_set_enable(const struct device *dev, bool enable)
 {
 	struct knob_data *data = dev->data;
-	motor_set_enable(&data->motor, enable);
+	motor_set_enable(&data->motor, enable && data->mode != KNOB_DISABLE);
 }
 
 void knob_set_encoder_report(const struct device *dev, bool report)
@@ -325,16 +325,10 @@ int knob_init(const struct device *dev)
 	pid_set(&data->motor.pid_velocity, 0.1f, 0.0f, 0.0f);
 	pid_set(&data->motor.pid_angle, 80.0f, 0.0f, 0.7f);
 
-#if 1
 	if (!knob_calibrate_auto(dev)) {
 		return -EIO;
 	}
 
-	knob_set_enable(dev, true);
-	knob_set_encoder_report(dev, true);
-	knob_set_mode(dev, KNOB_ENCODER);
-#endif
-
 	k_thread_create(&data->thread, data->thread_stack, CONFIG_KNOB_THREAD_STACK_SIZE,
 			(k_thread_entry_t)knob_thread, (void *)dev, 0, NULL,
 			K_PRIO_COOP(CONFIG_KNOB_THREAD_PRIORITY), 0, K_NO_WAIT);
@@ -347,7 +341,7 @@ int knob_init(const struct device *dev)
 		.mode = KNOB_DISABLE,                                                              \
 		.position_min = 3.3f,                                                              \
 		.position_max = 5.1f,                                                              \
-		.encoder_report = true,                                                            \
+		.encoder_report = false,                                                           \
 		.encoder_ppr = DT_INST_PROP_OR(n, ppr, 24),                                        \
 	};                                                                                         \
                                                                                                    \