Change task messages to events

Signed-off-by: Randall Spangler <rspangler@chromium.org>

BUG=chrome-os-partner:7461
TEST=manual

make BOARD={bds,link,daisy}
make tests
flash link system and make sure it boots

Change-Id: I1241a1895c083e387e38ddab01ac346ca4474eb9

23 files changed, 127 insertions, 143 deletions

diff --git a/chip/lm4/i2c.c b/chip/lm4/i2c.c
index 5a2116a5a1..a6e8a5c77c 100644
--- a/chip/lm4/i2c.c
+++ b/chip/lm4/i2c.c
@@ -35,17 +35,17 @@ static struct mutex port_mutex[NUM_PORTS];
 static int wait_idle(int port)
 {
 	int i;
-	int wait_msg;
+	int event;
 
 	i = LM4_I2C_MCS(port);
 	while (i & 0x01) {
 		/* Port is busy, so wait for the interrupt */
 		task_waiting_on_port[port] = task_get_current();
 		LM4_I2C_MIMR(port) = 0x03;
-		wait_msg = task_wait_msg(1000000);
+		event = task_wait_event(1000000);
 		LM4_I2C_MIMR(port) = 0x00;
 		task_waiting_on_port[port] = TASK_ID_INVALID;
-		if (wait_msg == 1 << TASK_ID_TIMER)
+		if (event == TASK_EVENT_TIMER)
 			return EC_ERROR_TIMEOUT;
 
 		i = LM4_I2C_MCS(port);
@@ -271,9 +271,9 @@ static void handle_interrupt(int port)
 	LM4_I2C_MICR(port) = LM4_I2C_MMIS(port);
 
 	/* Wake up the task which was waiting on the interrupt, if any */
-	/* TODO: send message based on I2C port number? */
+	/* TODO: set event based on I2C port number? */
 	if (id != TASK_ID_INVALID)
-		task_send_msg(id, id, 0);
+		task_wake(id);
 }
 
 
diff --git a/chip/lm4/keyboard_scan.c b/chip/lm4/keyboard_scan.c
index 0387f93435..32a2bd2423 100644
--- a/chip/lm4/keyboard_scan.c
+++ b/chip/lm4/keyboard_scan.c
@@ -381,7 +381,7 @@ void keyboard_scan_task(void)
 
 	while (1) {
 		wait_for_interrupt();
-		task_wait_msg(-1);
+		task_wait_event(-1);
 
 		enter_polling_mode();
 		/* Busy polling keyboard state. */
@@ -412,9 +412,8 @@ static void matrix_interrupt(void)
 {
 	uint32_t ris = clear_matrix_interrupt_status();
 
-	if (ris) {
-		task_send_msg(TASK_ID_KEYSCAN, TASK_ID_KEYSCAN, 0);
-	}
+	if (ris)
+		task_wake(TASK_ID_KEYSCAN);
 }
 DECLARE_IRQ(KB_SCAN_ROW_IRQ, matrix_interrupt, 3);
 
diff --git a/chip/lm4/lpc.c b/chip/lm4/lpc.c
index e07b54d66e..931ddd6bec 100644
--- a/chip/lm4/lpc.c
+++ b/chip/lm4/lpc.c
@@ -372,7 +372,7 @@ static void lpc_interrupt(void)
 	}
 	if (mis & LM4_LPC_INT_MASK(LPC_CH_KEYBOARD, 1)) {
 		/* Host picks up the data, try to send remaining bytes */
-		task_send_msg(TASK_ID_I8042CMD, TASK_ID_I8042CMD, 0);
+		task_wake(TASK_ID_I8042CMD);
 	}
 #endif
 
diff --git a/chip/lm4/power_button.c b/chip/lm4/power_button.c
index 7fdc5f633a..24af579690 100644
--- a/chip/lm4/power_button.c
+++ b/chip/lm4/power_button.c
@@ -225,7 +225,7 @@ void power_button_interrupt(enum gpio_signal signal)
          * remainder of the interval.  The alternative would be to have the
          * task wake up _every_ debounce_us on its own; that's less desirable
          * when the EC should be sleeping. */
-	task_send_msg(TASK_ID_POWERBTN, TASK_ID_POWERBTN, 0);
+	task_wake(TASK_ID_POWERBTN);
 }
 
 
@@ -314,7 +314,7 @@ void power_button_task(void)
 			 * early.) */
 			uart_printf("[%T PB task %d wait %d]\n",
 				    pwrbtn_state, d);
-			task_wait_msg(d);
+			task_wait_event(d);
 		}
 	}
 }
diff --git a/chip/lm4/pwm.c b/chip/lm4/pwm.c
index d33c287aa6..7fa935dbee 100644
--- a/chip/lm4/pwm.c
+++ b/chip/lm4/pwm.c
@@ -14,6 +14,7 @@
 #include "util.h"
 #include "task.h"
 #include "thermal.h"
+#include "timer.h"
 #include "lpc.h"
 #include "lpc_commands.h"
 
@@ -122,8 +123,7 @@ void pwm_task(void)
 {
 	while (1) {
 		update_lpc_mapped_memory();
-		/* Wait 1s */
-		task_wait_msg(1000000);
+		usleep(1000000);
 	}
 }
 
diff --git a/chip/stm32l/keyboard_scan.c b/chip/stm32l/keyboard_scan.c
index 8ae1c7ff59..5223f041d7 100644
--- a/chip/stm32l/keyboard_scan.c
+++ b/chip/stm32l/keyboard_scan.c
@@ -425,7 +425,7 @@ void keyboard_scan_task(void)
 
 	while (1) {
 		wait_for_interrupt();
-		task_wait_msg(-1);
+		task_wait_event(-1);
 
 		enter_polling_mode();
 		/* Busy polling keyboard state. */
@@ -453,7 +453,7 @@ void keyboard_scan_task(void)
 
 void matrix_interrupt(enum gpio_signal signal)
 {
-	task_send_msg(TASK_ID_KEYSCAN, TASK_ID_KEYSCAN, 0);
+	task_wake(TASK_ID_KEYSCAN);
 }
 
 int keyboard_has_char()
diff --git a/common/console.c b/common/console.c
index 130b7e4ef1..fc34fb4872 100644
--- a/common/console.c
+++ b/common/console.c
@@ -21,7 +21,7 @@ extern const struct console_command __cmds_end[];
 void console_has_input(void)
 {
 	/* Wake up the console task */
-	task_send_msg(TASK_ID_CONSOLE, TASK_ID_CONSOLE, 0);
+	task_wake(TASK_ID_CONSOLE);
 }
 
 
@@ -131,7 +131,7 @@ void console_task(void)
 	while (1) {
 		console_process();
 		/* wait for the next command message */
-		task_wait_msg(-1);
+		task_wait_event(-1);
 	}
 }
 
diff --git a/common/gaia_power.c b/common/gaia_power.c
index bd532acc60..7e381c5868 100644
--- a/common/gaia_power.c
+++ b/common/gaia_power.c
@@ -54,8 +54,8 @@ static int wait_in_signal(enum gpio_signal signal, int value, int timeout)
 		gpio_get_level(signal) != value) {
 		now = get_time();
 		if ((now.val >= deadline.val) ||
-			(task_wait_msg(deadline.val - now.val) ==
-			 (1 << TASK_ID_TIMER))) {
+			(task_wait_event(deadline.val - now.val) ==
+			 TASK_EVENT_TIMER)) {
 			uart_printf("Timeout waiting for GPIO %d\n", signal);
 			return EC_ERROR_TIMEOUT;
 		}
@@ -77,7 +77,7 @@ static void wait_for_power_off(void)
 		/* wait for power button press or XPSHOLD falling edge */
 		while ((gpio_get_level(GPIO_EC_PWRON) == 0) &&
 			(gpio_get_level(GPIO_SOC1V8_XPSHOLD) == 1)) {
-				task_wait_msg(-1);
+				task_wait_event(-1);
 		}
 		/* XPSHOLD released by AP : shutdown immediatly */
 		if (gpio_get_level(GPIO_SOC1V8_XPSHOLD) == 0)
@@ -89,8 +89,8 @@ static void wait_for_power_off(void)
 			(gpio_get_level(GPIO_SOC1V8_XPSHOLD) == 1)) {
 			now = get_time();
 			if ((now.val >= deadline.val) ||
-				(task_wait_msg(deadline.val - now.val) ==
-				 (1 << TASK_ID_TIMER)))
+				(task_wait_event(deadline.val - now.val) ==
+				 TASK_EVENT_TIMER))
 					return;
 		}
 	}
@@ -99,7 +99,7 @@ static void wait_for_power_off(void)
 void gaia_power_event(enum gpio_signal signal)
 {
 	/* Wake up the task */
-	task_send_msg(TASK_ID_GAIAPOWER, TASK_ID_GAIAPOWER, 0);
+	task_wake(TASK_ID_GAIAPOWER);
 }
 
 int gaia_power_init(void)
@@ -197,7 +197,7 @@ static int command_force_power(int argc, char **argv)
 	force_signal = GPIO_EC_PWRON;
 	force_value = 1;
 	/* Wake up the task */
-	task_send_msg(TASK_ID_GAIAPOWER, TASK_ID_GAIAPOWER, 0);
+	task_wake(TASK_ID_GAIAPOWER);
 	/* wait 100 ms */
 	usleep(100000);
 	/* release power button */
diff --git a/common/host_command.c b/common/host_command.c
index 671fd93047..cf66b6e057 100644
--- a/common/host_command.c
+++ b/common/host_command.c
@@ -15,6 +15,8 @@
 #include "uart.h"
 #include "util.h"
 
+#define TASK_EVENT_SLOT(n) TASK_EVENT_CUSTOM(1 << n)
+
 static int host_command[2];
 
 /* Host commands are described in a special section */
@@ -41,9 +43,8 @@ void host_command_received(int slot, int command)
 	/* Save the command */
 	host_command[slot] = command;
 
-	/* Wake up the task to handle the command.  Use the slot as
-	 * the task ID. */
-	task_send_msg(TASK_ID_HOSTCMD, slot, 0);
+	/* Wake up the task to handle the command for the slot */
+	task_set_event(TASK_ID_HOSTCMD, TASK_EVENT_SLOT(slot), 0);
 }
 
 
@@ -161,13 +162,12 @@ void host_command_task(void)
 	host_command_init();
 
 	while (1) {
-		/* wait for the next command message */
-		int m = task_wait_msg(-1);
+		/* wait for the next command event */
+		int evt = task_wait_event(-1);
 		/* process it */
-		/* TODO: use message flags to determine which slots */
-		if (m & 0x01)
+		if (evt & TASK_EVENT_SLOT(0))
 			command_process(0);
-		if (m & 0x02)
+		if (evt & TASK_EVENT_SLOT(1))
 			command_process(1);
 	}
 }
diff --git a/common/i8042.c b/common/i8042.c
index 7bf7a55de9..5db0c98388 100644
--- a/common/i8042.c
+++ b/common/i8042.c
@@ -98,7 +98,7 @@ void i8042_command_task(void)
 {
 	while (1) {
 		/* Either a new byte to host or host picking up can un-block. */
-		task_wait_msg(-1);
+		task_wait_event(-1);
 
 		while (1) {
 			uint8_t chr;
@@ -144,7 +144,7 @@ enum ec_error_list i8042_send_to_host(int len, uint8_t *to_host)
 	enq_to_host(len, to_host);
 
 	/* Wake up the task to handle the command */
-	task_send_msg(TASK_ID_I8042CMD, TASK_ID_I8042CMD, 0);
+	task_wake(TASK_ID_I8042CMD);
 
 	return EC_SUCCESS;
 }
diff --git a/common/temp_sensor.c b/common/temp_sensor.c
index 7b0e6dfa10..40d245bc0c 100644
--- a/common/temp_sensor.c
+++ b/common/temp_sensor.c
@@ -17,6 +17,7 @@
 #include "task.h"
 #include "temp_sensor.h"
 #include "thermal.h"
+#include "timer.h"
 #include "tmp006.h"
 #include "uart.h"
 #include "util.h"
@@ -93,8 +94,7 @@ void temp_sensor_task(void)
 	while (1) {
 		poll_all_sensors();
 		update_lpc_mapped_memory();
-		/* Wait 1s */
-		task_wait_msg(1000000);
+		usleep(1000000);
 	}
 }
 
diff --git a/common/thermal.c b/common/thermal.c
index f2e53c55b5..866f857d32 100644
--- a/common/thermal.c
+++ b/common/thermal.c
@@ -15,6 +15,7 @@
 #include "task.h"
 #include "temp_sensor.h"
 #include "thermal.h"
+#include "timer.h"
 #include "uart.h"
 #include "util.h"
 #include "x86_power.h"
@@ -193,8 +194,7 @@ void thermal_task(void)
 {
 	while (1) {
 		thermal_process();
-		/* Wait 1s */
-		task_wait_msg(1000000);
+		usleep(1000000);
 	}
 }
 
diff --git a/common/vboot.c b/common/vboot.c
index ba05f2b4ba..727a92ef4b 100644
--- a/common/vboot.c
+++ b/common/vboot.c
@@ -20,11 +20,13 @@ static void jump_to_other_image(void)
 	if (system_get_image_copy() != SYSTEM_IMAGE_RO)
 		return;
 
+#ifdef CONFIG_TASK_KEYSCAN
 	/* Don't jump if recovery requested */
 	if (keyboard_scan_recovery_pressed()) {
 		uart_puts("Vboot staying in RO because key pressed.\n");
 		return;
 	}
+#endif
 
 	/* Don't jump if we're in RO becuase we jumped there (this keeps us
 	 * from jumping to RO only to jump right back). */
diff --git a/common/x86_power.c b/common/x86_power.c
index eeea520aac..4c4d39c949 100644
--- a/common/x86_power.c
+++ b/common/x86_power.c
@@ -149,7 +149,7 @@ static int wait_in_signals(uint32_t want)
 	in_want = want;
 
 	while ((in_signals & in_want) != in_want) {
-		if (task_wait_msg(DEFAULT_TIMEOUT) == (1 << TASK_ID_TIMER)) {
+		if (task_wait_event(DEFAULT_TIMEOUT) == TASK_EVENT_TIMER) {
 			update_in_signals();
 			uart_printf("[x86 power timeout on input; "
 				    "wanted 0x%04x, got 0x%04x]\n",
@@ -240,7 +240,7 @@ void x86_power_interrupt(enum gpio_signal signal)
 	update_in_signals();
 
 	/* Wake up the task */
-	task_send_msg(TASK_ID_X86POWER, TASK_ID_X86POWER, 0);
+	task_wake(TASK_ID_X86POWER);
 }
 
 /*****************************************************************************/
@@ -426,7 +426,7 @@ void x86_power_task(void)
 
 			/* Otherwise, steady state; wait for a message */
 			in_want = 0;
-			task_wait_msg(-1);
+			task_wait_event(-1);
 			break;
 
 		case X86_S3:
@@ -442,7 +442,7 @@ void x86_power_task(void)
 
 			/* Otherwise, steady state; wait for a message */
 			in_want = 0;
-			task_wait_msg(-1);
+			task_wait_event(-1);
 			break;
 
 		case X86_S0:
@@ -454,7 +454,7 @@ void x86_power_task(void)
 
 			/* Otherwise, steady state; wait for a message */
 			in_want = 0;
-			task_wait_msg(-1);
+			task_wait_event(-1);
 		}
 	}
 }
diff --git a/core/cortex-m/task.c b/core/cortex-m/task.c
index 246147b7c7..1f15bf5df6 100644
--- a/core/cortex-m/task.c
+++ b/core/cortex-m/task.c
@@ -57,7 +57,7 @@ static void task_exit_trap(void)
 	uart_printf("[Task %d (%s) exited!]\n", i, task_names[i]);
 	/* Exited tasks simply sleep forever */
 	while (1)
-		task_wait_msg(-1);
+		task_wait_event(-1);
 }
 
 
@@ -198,15 +198,6 @@ void __schedule(int desched, int resched)
 }
 
 
-/**
- * Change the task scheduled after returning from the exception.
- *
- * If task_send_msg has been called and has set need_resched flag,
- * we re-compute which task is running and eventually swap the context
- * saved on the process stack to restore the new one at exception exit.
- *
- * it must be called from interrupt context !
- */
 void task_resched_if_needed(void *excep_return)
 {
 	/**
@@ -220,7 +211,7 @@ void task_resched_if_needed(void *excep_return)
 }
 
 
-static uint32_t __wait_msg(int timeout_us, task_id_t resched)
+static uint32_t __wait_evt(int timeout_us, task_id_t resched)
 {
 	task_ *tsk = __get_current();
 	task_id_t me = tsk - tasks;
@@ -247,17 +238,13 @@ static uint32_t __wait_msg(int timeout_us, task_id_t resched)
 }
 
 
-uint32_t task_send_msg(task_id_t tskid, task_id_t from, int wait)
+uint32_t task_set_event(task_id_t tskid, uint32_t event, int wait)
 {
 	task_ *receiver = __task_id_to_ptr(tskid);
 	ASSERT(receiver);
 
-	if (from == TASK_ID_CURRENT) {
-		from = task_get_current();
-	}
-
 	/* set the event bit in the receiver message bitmap */
-	atomic_or(&receiver->events, 1 << from);
+	atomic_or(&receiver->events, event);
 
 	/* Re-schedule if priorities have changed */
 	if (in_interrupt_context()) {
@@ -266,7 +253,7 @@ uint32_t task_send_msg(task_id_t tskid, task_id_t from, int wait)
 		need_resched = 1;
 	} else {
 		if (wait)
-			return __wait_msg(-1, tskid);
+			return __wait_evt(-1, tskid);
 		else
 			__schedule(0, tskid);
 	}
@@ -275,9 +262,9 @@ uint32_t task_send_msg(task_id_t tskid, task_id_t from, int wait)
 }
 
 
-uint32_t task_wait_msg(int timeout_us)
+uint32_t task_wait_event(int timeout_us)
 {
-	return __wait_msg(timeout_us, TASK_ID_IDLE);
+	return __wait_evt(timeout_us, TASK_ID_IDLE);
 }
 
 
@@ -354,7 +341,7 @@ void mutex_lock(struct mutex *mtx)
 		 */
 		if (value == 2) {
 			/* contention on the mutex */
-			task_wait_msg(0);
+			task_wait_event(0);
 		}
 	} while (value);
 
@@ -374,11 +361,11 @@ void mutex_unlock(struct mutex *mtx)
 	while (waiters) {
 		task_id_t id = 31 - __builtin_clz(waiters);
 		/* somebody is waiting on the mutex */
-		task_send_msg(id, TASK_ID_MUTEX, 0);
+		task_set_event(id, TASK_EVENT_MUTEX, 0);
 		waiters &= ~(1 << id);
 	}
 	/* Ensure no event is remaining from mutex wake-up */
-	atomic_clear(&tsk->events, 1 << TASK_ID_MUTEX);
+	atomic_clear(&tsk->events, TASK_EVENT_MUTEX);
 }
 
 
diff --git a/core/cortex-m/timer.c b/core/cortex-m/timer.c
index 9a32d6fa66..a679e8d7b5 100644
--- a/core/cortex-m/timer.c
+++ b/core/cortex-m/timer.c
@@ -34,7 +34,7 @@ static void expire_timer(task_id_t tskid)
 	/* we are done with this timer */
 	atomic_clear(&timer_running, 1<<tskid);
 	/* wake up the taks waiting for this timer */
-	task_send_msg(tskid, TASK_ID_TIMER, 0);
+	task_set_event(tskid, TASK_EVENT_TIMER, 0);
 }
 
 /**
@@ -130,12 +130,12 @@ void usleep(unsigned us)
 	uint32_t evt = 0;
 	ASSERT(us);
 	do {
-		evt |= task_wait_msg(us);
-	} while (!(evt & (1 << TASK_ID_TIMER)));
+		evt |= task_wait_event(us);
+	} while (!(evt & TASK_EVENT_TIMER));
 	/* re-queue other events which happened in the meanwhile */
 	if (evt)
 		atomic_or(task_get_event_bitmap(task_get_current()),
-		          evt & ~(1 << TASK_ID_TIMER));
+			  evt & ~TASK_EVENT_TIMER);
 }
 
 
diff --git a/include/task.h b/include/task.h
index b5e57e736b..5644d4078e 100644
--- a/include/task.h
+++ b/include/task.h
@@ -1,4 +1,4 @@
-/* Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
+/* Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
@@ -11,66 +11,72 @@
 #include "common.h"
 #include "task_id.h"
 
-/* Disables CPU interrupt bit. This might break the system so think really hard
+/* Task event bitmasks */
+#define TASK_EVENT_CUSTOM(x) (x & 0x1fffffff)
+#define TASK_EVENT_WAKE   (1 << 29)  /* task_wake() called on task */
+#define TASK_EVENT_MUTEX  (1 << 30)  /* Mutex unlocking */
+#define TASK_EVENT_TIMER  (1 << 31)  /* Timer expired.  For example,
+				      * task_wait_event() timed out before
+				      * receiving another event. */
+
+/* Disable CPU interrupt bit. This might break the system so think really hard
  * before using these. There are usually better ways of accomplishing this. */
 void interrupt_disable(void);
 
-/* Enables CPU interrupt */
+/* Enable CPU interrupt bit. */
 void interrupt_enable(void);
 
-/**
- * Return true if we are in interrupt context
- */
+/* Return true if we are in interrupt context. */
 inline int in_interrupt_context(void);
 
-/**
- * Send a message to a task and wake it up if it is higher priority than us
+/* Set an event for task <tskid> and wake it up if it is higher priority than
+ * the current task.
  *
- * tskid : identifier of the receiver task
- * from : identifier of the sender of the message
- * wait : after sending, de-schedule the calling task to wait for the answer
+ * event : event bitmap to set (TASK_EVENT_*)
  *
- * returns the bitmap of events which have occured.
+ * If wait!=0, after setting the event, de-schedule the calling task to wait
+ * for a response event, then return the bitmap of events which have occured
+ * (same as task_wait_event()).  Ignored in interrupt context.
  *
- * Can be called both in interrupt context and task context.
- */
-uint32_t task_send_msg(task_id_t tskid, task_id_t from, int wait);
+ * If wait==0, returns 0.
+ *
+ * Can be called both in interrupt context and task context. */
+uint32_t task_set_event(task_id_t tskid, uint32_t event, int wait);
+
+/* Wake a task.  This sends it the TASK_EVENT_WAKE event. */
+static inline void task_wake(task_id_t tskid)
+{
+	task_set_event(tskid, TASK_EVENT_WAKE, 0);
+}
 
-/**
- * Return the identifier of the task currently running
+/* Return the identifier of the task currently running.
  *
- * when called in interrupt context, returns TASK_ID_INVALID
- */
+ * When called in interrupt context, returns TASK_ID_INVALID. */
 task_id_t task_get_current(void);
 
-/**
- * Return a pointer to the bitmap of received events of the task.
- */
+/* Return a pointer to the bitmap of events of the task. */
 uint32_t *task_get_event_bitmap(task_id_t tsk);
 
-/**
- * Waits for the incoming next message.
+/* Wait for the next event.
  *
- * if an event is already pending, it returns it immediatly, else it
- * de-schedules the calling task and wake up the next one in the priority order
+ * If one or more events are already pending, returns immediately.  Otherwise,
+ * it de-schedules the calling task and wakes up the next one in the priority
+ * order.
  *
- * if timeout_us > 0, it also sets a timer to produce an event after the
- * specified micro-second duration.
+ * If timeout_us > 0, it also sets a timer to produce the TASK_EVENT_TIMER
+ * event after the specified micro-second duration.
  *
- * returns the bitmap of received events (and clear it atomically).
- */
-uint32_t task_wait_msg(int timeout_us);
+ * Returns the bitmap of received events (and clears it atomically). */
+uint32_t task_wait_event(int timeout_us);
 
-/**
- * Changes the task scheduled after returning from the exception.
+/* Change the task scheduled after returning from the exception.
  *
- * If task_send_msg has been called and has set need_resched flag,
- * we re-compute which task is running and eventually swap the context
+ * If task_send_event() has been called and has set need_resched flag,
+ * re-computes which task is running and eventually swaps the context
  * saved on the process stack to restore the new one at exception exit.
  *
- * it must be called from interrupt context !
- * and it is designed to be the last call of the interrupt handler.
- */
+ * This must be called from interrupt context(!) and is designed to be the
+ * last call of the interrupt handler. */
 void task_resched_if_needed(void *excep_return);
 
 /* Initializes tasks and interrupt controller. */
@@ -93,12 +99,10 @@ struct mutex {
 	uint32_t waiters;
 };
 
-/**
- * try to lock the mutex mtx
- * and de-schedule the task if it is already locked by another task.
+/* Try to lock the mutex mtx and de-schedule the current task if mtx is already
+ * locked by another task.
  *
- * Should not be used in interrupt context !
- */
+ * Must not be used in interrupt context! */
 void mutex_lock(struct mutex *mtx);
 
 /* Release a mutex previously locked by the same task. */
@@ -113,10 +117,8 @@ struct irq_priority {
 #define IRQ_BUILD_NAME(prefix, irqnum, postfix) prefix ## irqnum ## postfix
 #define IRQ_HANDLER(irqname)  IRQ_BUILD_NAME(irq_,irqname,_handler)
 
-/**
- * Connects the interrupt handler "routine" to the irq number "irq" and
- * ensures it is enabled in the interrupt controller with the right priority.
- */
+/* Connects the interrupt handler "routine" to the irq number "irq" and ensures
+ * it is enabled in the interrupt controller with the right priority. */
 #define DECLARE_IRQ(irq, routine, priority)                     \
 	void IRQ_HANDLER(irq)(void)				\
 	{							\
diff --git a/include/task_id.h b/include/task_id.h
index a2fb17ca7a..493082a0b5 100644
--- a/include/task_id.h
+++ b/include/task_id.h
@@ -32,9 +32,6 @@ enum {
 	/* Number of tasks */
 	TASK_ID_COUNT,
 	/* Special task identifiers */
-	TASK_ID_MUTEX   = 0x1e, /* signal mutex unlocking */
-	TASK_ID_TIMER   = 0x1f, /* message from an expired timer */
-	TASK_ID_CURRENT = 0xfe, /* the currently running task */
 	TASK_ID_INVALID = 0xff  /* unable to find the task */
 };
 #undef TASK
diff --git a/test/mutex.c b/test/mutex.c
index a5b7244e36..9fc1cd76b7 100644
--- a/test/mutex.c
+++ b/test/mutex.c
@@ -30,16 +30,16 @@ int mutex_random_task(void *unused)
 	/* wait to be activated */
 
 	while (1) {
-		task_wait_msg(0);
+		task_wait_event(0);
 		uart_printf("%c+\n", letter);
 		mutex_lock(&mtx);
 		uart_printf("%c=\n", letter);
-		task_wait_msg(0);
+		task_wait_event(0);
 		uart_printf("%c-\n", letter);
 		mutex_unlock(&mtx);
 	}
 
-	task_wait_msg(0);
+	task_wait_event(0);
 
 	return EC_SUCCESS;
 }
@@ -50,15 +50,15 @@ int mutex_second_task(void *unused)
 
 	uart_printf("\n[Mutex second task %d]\n", id);
 
-	task_wait_msg(0);
+	task_wait_event(0);
 	uart_printf("MTX2: locking...");
 	mutex_lock(&mtx);
 	uart_printf("done\n");
-	task_send_msg(TASK_ID_MTX1, 1, 0);
+	task_wake(TASK_ID_MTX1);
 	uart_printf("MTX2: unlocking...\n");
 	mutex_unlock(&mtx);
 
-	task_wait_msg(0);
+	task_wait_event(0);
 
 	return EC_SUCCESS;
 }
@@ -85,7 +85,7 @@ int mutex_main_task(void *unused)
 	/* --- Serialization to test simple contention --- */
 	uart_printf("Simple contention :\n");
 	/* lock the mutex from the other task */
-	task_send_msg(TASK_ID_MTX2, 1, 1);
+	task_set_event(TASK_ID_MTX2, TASK_EVENT_WAKE, 1);
 	/* block on the mutex */
 	uart_printf("MTX1: blocking...\n");
 	mutex_lock(&mtx);
@@ -96,17 +96,17 @@ int mutex_main_task(void *unused)
 	uart_printf("Massive locking/unlocking :\n");
 	for (i = 0; i < 500; i++) {
 		/* Wake up a random task */
-		task_send_msg(RANDOM_TASK(rtask), 1, 0);
+		task_wake(RANDOM_TASK(rtask));
 		/* next pseudo random delay */
 		rtask = prng(rtask);
 		/* Wait for a "random" period */
-		task_wait_msg(PERIOD_US(rdelay));
+		task_wait_event(PERIOD_US(rdelay));
 		/* next pseudo random delay */
 		rdelay = prng(rdelay);
 	}
 
 	uart_printf("Test done.\n");
-	task_wait_msg(0);
+	task_wait_event(0);
 
 	return EC_SUCCESS;
 }
diff --git a/test/pingpong.c b/test/pingpong.c
index 18115060d3..e6571080c5 100644
--- a/test/pingpong.c
+++ b/test/pingpong.c
@@ -1,7 +1,6 @@
-/* Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
+/* Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
- * Copyright 2011 Google Inc.
  *
  * Tasks for scheduling test.
  */
@@ -24,7 +23,7 @@ int TaskAbc(void *data)
 	while (1) {
 		uart_puts(string);
 		uart_flush_output();
-		task_send_msg(next, TASK_ID_CURRENT, 1);
+		task_set_event(next, TASK_EVENT_WAKE, 1);
 	}
 
 	return EC_SUCCESS;
diff --git a/test/powerdemo.c b/test/powerdemo.c
index c809c1eac5..aabe4c8825 100644
--- a/test/powerdemo.c
+++ b/test/powerdemo.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
+/* Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
@@ -180,7 +180,7 @@ int power_demo_task(void)
 	power_demo_init();
 
 	/* suspend this task forever */
-	task_wait_msg(-1);
+	task_wait_event(-1);
 
 	return EC_SUCCESS;
 }
diff --git a/test/timer_calib.c b/test/timer_calib.c
index 1169491c86..86da6479ff 100644
--- a/test/timer_calib.c
+++ b/test/timer_calib.c
@@ -1,7 +1,6 @@
-/* Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
+/* Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
- * Copyright 2011 Google Inc.
  *
  * Tasks for scheduling test.
  */
@@ -35,7 +34,7 @@ int timer_calib_task(void *data)
 	usleep(1000000);
 	t1 = get_time();
 	uart_printf("done. delay = %d us\n", difftime(t0, t1));
-	
+
 	/* try small usleep */
 	uart_printf("- short sleep :\n");
 	uart_flush_output();
@@ -49,7 +48,7 @@ int timer_calib_task(void *data)
 
 	uart_printf("Done.\n");
 	/* sleep forever */
-	task_wait_msg(-1);
+	task_wait_event(-1);
 
 	return EC_SUCCESS;
 }
diff --git a/test/timer_dos.c b/test/timer_dos.c
index b0c37a4eaf..63ad7dd657 100644
--- a/test/timer_dos.c
+++ b/test/timer_dos.c
@@ -1,7 +1,6 @@
-/* Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
+/* Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
- * Copyright 2011 Google Inc.
  *
  * Tasks for timer test.
  */
@@ -29,7 +28,7 @@ int TaskTimer(void *seed)
 
 	while (1) {
 		/* Wait for a "random" period */
-		task_wait_msg(PERIOD_US(num));
+		task_wait_event(PERIOD_US(num));
 		uart_printf("%01d\n", id);
 		/* next pseudo random delay */
 		num = prng(num);