link: EC reclaims fan control on AP shutdown

Previously, if the AP took fan control, the EC would never take it
back.  This meant the EC would leave the fan off even if the system
was sitting at the INSERT screen or booted an alternate OS.

BUG=chrome-os-partner:15189
BRANCH=link
TEST=manual

- boot system
- from EC console, fanset 0
- faninfo shows fan at 0rpm
- from root shell, crossystem recovery_request=123 && reboot
- wait a few mins
- faninfo should show fan spinning again

Original-Change-Id: I534c9978194085467f1df6eae971c55d4e8083be
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/35309
(cherry picked from commit b00a446ec57323f84002722523783351f19e41b1)

Change-Id: Ic339a7fffab46f103aee3d56c63d68570d66a1a5
Reviewed-on: https://gerrit.chromium.org/gerrit/35674
Reviewed-by: Rong Chang <rongchang@chromium.org>
Tested-by: Rong Chang <rongchang@chromium.org>

5 files changed, 49 insertions, 27 deletions

diff --git a/chip/lm4/pwm.c b/chip/lm4/pwm.c
index 043a8b556c..431f04036f 100644
--- a/chip/lm4/pwm.c
+++ b/chip/lm4/pwm.c
@@ -205,7 +205,7 @@ static int command_fan_set(int argc, char **argv)
 
 #ifdef CONFIG_TASK_THERMAL
 	/* Disable thermal engine automatic fan control. */
-	thermal_toggle_auto_fan_ctrl(0);
+	thermal_control_fan(0);
 #endif
 
 	return pwm_set_fan_target_rpm(rpm);
@@ -236,7 +236,7 @@ int pwm_set_fan_duty(int percent)
 
 #ifdef CONFIG_TASK_THERMAL
 	/* Disable thermal engine automatic fan control. */
-	thermal_toggle_auto_fan_ctrl(0);
+	thermal_control_fan(0);
 #endif
 
         /* Set the duty cycle */
diff --git a/common/pwm_commands.c b/common/pwm_commands.c
index 8cc4d8dc2d..b23f2d82d2 100644
--- a/common/pwm_commands.c
+++ b/common/pwm_commands.c
@@ -28,7 +28,7 @@ int pwm_command_set_fan_target_rpm(struct host_cmd_handler_args *args)
 	const struct ec_params_pwm_set_fan_target_rpm *p = args->params;
 
 #ifdef CONFIG_TASK_THERMAL
-	thermal_toggle_auto_fan_ctrl(0);
+	thermal_control_fan(0);
 #endif
 	pwm_set_fan_target_rpm(p->rpm);
 
diff --git a/common/thermal.c b/common/thermal.c
index a300497bde..b189075af1 100644
--- a/common/thermal.c
+++ b/common/thermal.c
@@ -9,6 +9,7 @@
 #include "common.h"
 #include "console.h"
 #include "gpio.h"
+#include "hooks.h"
 #include "host_command.h"
 #include "pwm.h"
 #include "task.h"
@@ -55,23 +56,22 @@ static int8_t *fan_threshold_reached = overheated + THRESHOLD_COUNT;
 
 static int fan_ctrl_on = 1;
 
-
-int thermal_set_threshold(enum temp_sensor_type type, int threshold_id, int value)
+int thermal_set_threshold(enum temp_sensor_type type, int threshold_id,
+			  int value)
 {
 	if (type < 0 || type >= TEMP_SENSOR_TYPE_COUNT)
-		return -1;
+		return EC_ERROR_INVAL;
 	if (threshold_id < 0 ||
 	    threshold_id >= THRESHOLD_COUNT + THERMAL_FAN_STEPS)
-		return -1;
+		return EC_ERROR_INVAL;
 	if (value < 0)
-		return -1;
+		return EC_ERROR_INVAL;
 
 	thermal_config[type].thresholds[threshold_id] = value;
 
 	return EC_SUCCESS;
 }
 
-
 int thermal_get_threshold(enum temp_sensor_type type, int threshold_id)
 {
 	if (type < 0 || type >= TEMP_SENSOR_TYPE_COUNT)
@@ -83,10 +83,9 @@ int thermal_get_threshold(enum temp_sensor_type type, int threshold_id)
 	return thermal_config[type].thresholds[threshold_id];
 }
 
-
-int thermal_toggle_auto_fan_ctrl(int auto_fan_on)
+int thermal_control_fan(int enable)
 {
-	fan_ctrl_on = auto_fan_on;
+	fan_ctrl_on = enable;
 	return EC_SUCCESS;
 }
 
@@ -100,7 +99,6 @@ static void smi_sensor_failure_warning(void)
 	host_set_single_event(EC_HOST_EVENT_THERMAL);
 }
 
-
 /* TODO: When we need different overheated action for different boards,
  *       move these action to board-specific file. (e.g. board_thermal.c)
  */
@@ -135,7 +133,6 @@ static void overheated_action(void)
 	}
 }
 
-
 /* Update counter and check if the counter has reached delay limit.
  * Note that we have various delay period to prevent one error value triggering
  * overheated action. */
@@ -167,7 +164,6 @@ static inline void update_and_check_stat(int temp,
 		ot_count[sensor_id][threshold_id] = 0;
 }
 
-
 static void thermal_process(void)
 {
 	int i, j;
@@ -204,7 +200,6 @@ static void thermal_process(void)
 	overheated_action();
 }
 
-
 void thermal_task(void)
 {
 	while (1) {
@@ -213,6 +208,14 @@ void thermal_task(void)
 	}
 }
 
+static int thermal_shutdown(void)
+{
+	/* Take back fan control when the processor shuts down */
+	thermal_control_fan(1);
+	return EC_SUCCESS;
+}
+DECLARE_HOOK(HOOK_CHIPSET_SHUTDOWN, thermal_shutdown, HOOK_PRIO_DEFAULT);
+
 /*****************************************************************************/
 /* Console commands */
 
@@ -228,7 +231,6 @@ static void print_thermal_config(enum temp_sensor_type type)
 		 config->thresholds[THRESHOLD_POWER_DOWN]);
 }
 
-
 static void print_fan_stepping(enum temp_sensor_type type)
 {
 	const struct thermal_config_t *config = thermal_config + type;
@@ -242,7 +244,6 @@ static void print_fan_stepping(enum temp_sensor_type type)
 			 fan_speed[i+1]);
 }
 
-
 static int command_thermal_config(int argc, char **argv)
 {
 	char *e;
@@ -279,7 +280,6 @@ DECLARE_CONSOLE_COMMAND(thermalconf, command_thermal_config,
 			"Get/set thermal threshold temp",
 			NULL);
 
-
 static int command_fan_config(int argc, char **argv)
 {
 	char *e;
@@ -318,10 +318,9 @@ DECLARE_CONSOLE_COMMAND(thermalfan, command_fan_config,
 			"Get/set thermal threshold fan rpm",
 			NULL);
 
-
 static int command_thermal_auto_fan_ctrl(int argc, char **argv)
 {
-	return thermal_toggle_auto_fan_ctrl(1);
+	return thermal_control_fan(1);
 }
 DECLARE_CONSOLE_COMMAND(autofan, command_thermal_auto_fan_ctrl,
 			NULL,
diff --git a/common/thermal_commands.c b/common/thermal_commands.c
index 4638b60ac3..07261ce5fb 100644
--- a/common/thermal_commands.c
+++ b/common/thermal_commands.c
@@ -42,7 +42,7 @@ DECLARE_HOST_COMMAND(EC_CMD_THERMAL_GET_THRESHOLD,
 
 int thermal_command_auto_fan_ctrl(struct host_cmd_handler_args *args)
 {
-	if (thermal_toggle_auto_fan_ctrl(1))
+	if (thermal_control_fan(1))
 		return EC_RES_ERROR;
 	return EC_RES_SUCCESS;
 }
diff --git a/include/thermal.h b/include/thermal.h
index 6259504c01..8b32bf9773 100644
--- a/include/thermal.h
+++ b/include/thermal.h
@@ -46,13 +46,36 @@ struct thermal_config_t {
 	int16_t thresholds[THRESHOLD_COUNT + THERMAL_FAN_STEPS];
 };
 
-/* Set the threshold temperature value. Return -1 on error. */
-int thermal_set_threshold(enum temp_sensor_type type, int threshold_id, int value);
+/**
+ * Set a threshold temperature.
+ *
+ * @param type		Sensor type to set threshold for
+ * @param threshold_id	Threshold ID to set
+ * @param value		New threshold temperature in K, or
+ *			THERMAL_THRESHOLD_DISABLE to disable this threshold.
+ *
+ * @return EC_SUCCESS if success, non-zero if error.
+ */
+int thermal_set_threshold(enum temp_sensor_type type, int threshold_id,
+			  int value);
 
-/* Get the threshold temperature value. Return -1 on error. */
+/**
+ * Read a threshold temperature.
+ *
+ * @param type		Sensor type to get threshold for
+ * @param threshold_id	Threshold ID
+ *
+ * @return The threshold temperature in K, THERMAL_THRESHOLD_DISABLE if
+ * disabled, -1 if error.
+ */
 int thermal_get_threshold(enum temp_sensor_type type, int threshold_id);
 
-/* Toggle automatic fan speed control. Return -1 on error. */
-int thermal_toggle_auto_fan_ctrl(int auto_fan_on);
+/**
+ * Enable/disable automatic fan speed control
+ *
+ * @param enable	Enable (!=0) or disable (0) auto fan control
+ *
+ * @return EC_SUCCESS if successful, non-zero if error. */
+int thermal_control_fan(int enable);
 
 #endif  /* __CROS_EC_THERMAL_H */