Clean up pwm module

No functional changes.  But hey, I'm having lots of fun reformatting comments.

BUG=chrome-os-partner:15579
BRANCH=none
TEST=fanset -1; fanset 0; fanset 4000

Change-Id: Iddcea5b8e59fa6668cdd347b6d31155c28991521
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/36585
Reviewed-by: Bill Richardson <wfrichar@chromium.org>

4 files changed, 123 insertions, 118 deletions

diff --git a/chip/lm4/pwm.c b/chip/lm4/pwm.c
index 1ed448b74e..372e008943 100644
--- a/chip/lm4/pwm.c
+++ b/chip/lm4/pwm.c
@@ -34,7 +34,7 @@
 
 #define PWM_SYSJUMP_TAG 0x504d  /* "PM" */
 #define PWM_HOOK_VERSION 1
-/* the previous pwm state before reboot_ec. */
+/* Saved PWM state across sysjumps */
 struct pwm_state {
 	uint16_t fan_rpm;
 	uint8_t fan_en;
@@ -43,7 +43,9 @@ struct pwm_state {
 	char pad; /* Pad to multiple of 4 bytes. */
 };
 
-/* Configures the GPIOs for the fan module. */
+/**
+ * Configure the GPIOs for the pwm module.
+ */
 static void configure_gpios(void)
 {
 	/* PK6 alternate function 1 = channel 1 PWM */
@@ -52,14 +54,12 @@ static void configure_gpios(void)
 	gpio_set_alternate_function(LM4_GPIO_M, 0xc0, 1);
 }
 
-int pwm_enable_fan(int enable)
+void pwm_enable_fan(int enable)
 {
 	if (enable)
 		LM4_FAN_FANCTL |= (1 << FAN_CH_CPU);
 	else
 		LM4_FAN_FANCTL &= ~(1 << FAN_CH_CPU);
-
-	return EC_SUCCESS;
 }
 
 int pwm_get_fan_enabled(void)
@@ -101,7 +101,7 @@ int pwm_get_fan_target_rpm(void)
 	return (LM4_FAN_FANCMD(FAN_CH_CPU) & MAX_RPM) * CPU_FAN_SCALE;
 }
 
-int pwm_set_fan_target_rpm(int rpm)
+void pwm_set_fan_target_rpm(int rpm)
 {
 	/* Apply fan scaling */
 	if (rpm > 0)
@@ -112,17 +112,14 @@ int pwm_set_fan_target_rpm(int rpm)
 		rpm = MAX_RPM;
 
 	LM4_FAN_FANCMD(FAN_CH_CPU) = rpm;
-	return EC_SUCCESS;
 }
 
-int pwm_enable_keyboard_backlight(int enable)
+void pwm_enable_keyboard_backlight(int enable)
 {
 	if (enable)
 		LM4_FAN_FANCTL |= (1 << FAN_CH_KBLIGHT);
 	else
 		LM4_FAN_FANCTL &= ~(1 << FAN_CH_KBLIGHT);
-
-	return EC_SUCCESS;
 }
 
 int pwm_get_keyboard_backlight_enabled(void)
@@ -136,7 +133,7 @@ int pwm_get_keyboard_backlight(void)
 		MAX_PWM / 2) / MAX_PWM;
 }
 
-int pwm_set_keyboard_backlight(int percent)
+void pwm_set_keyboard_backlight(int percent)
 {
 	if (percent < 0)
 		percent = 0;
@@ -144,10 +141,9 @@ int pwm_set_keyboard_backlight(int percent)
 		percent = 100;
 
 	LM4_FAN_FANCMD(FAN_CH_KBLIGHT) = ((percent * MAX_PWM + 50) / 100) << 16;
-	return EC_SUCCESS;
 }
 
-int pwm_set_fan_duty(int percent)
+void pwm_set_fan_duty(int percent)
 {
 	int pwm;
 
@@ -171,12 +167,10 @@ int pwm_set_fan_duty(int percent)
 
 	/* Set the duty cycle */
 	LM4_FAN_FANCMD(FAN_CH_CPU) = pwm << 16;
-
-	return EC_SUCCESS;
 }
 
 /**
- * Return non-zero if fan is enabled but stalled
+ * Return non-zero if fan is enabled but stalled.
  */
 static int fan_is_stalled(void)
 {
@@ -209,7 +203,6 @@ void pwm_task(void)
 	}
 }
 
-
 /*****************************************************************************/
 /* Console commands */
 
@@ -256,7 +249,9 @@ static int command_fan_set(int argc, char **argv)
 	thermal_control_fan(0);
 #endif
 
-	return pwm_set_fan_target_rpm(rpm);
+	pwm_set_fan_target_rpm(rpm);
+
+	return EC_SUCCESS;
 }
 DECLARE_CONSOLE_COMMAND(fanset, command_fan_set,
 			"rpm",
@@ -287,18 +282,16 @@ DECLARE_CONSOLE_COMMAND(fanduty, ec_command_fan_duty,
 
 static int command_kblight(int argc, char **argv)
 {
-	int rv = EC_SUCCESS;
-
 	if (argc >= 2) {
 		char *e;
 		int i = strtoi(argv[1], &e, 0);
 		if (*e)
 			return EC_ERROR_PARAM1;
-		rv = pwm_set_keyboard_backlight(i);
+		pwm_set_keyboard_backlight(i);
 	}
 
 	ccprintf("Keyboard backlight: %d%%\n", pwm_get_keyboard_backlight());
-	return rv;
+	return EC_SUCCESS;
 }
 DECLARE_CONSOLE_COMMAND(kblight, command_kblight,
 			"percent",
@@ -306,7 +299,76 @@ DECLARE_CONSOLE_COMMAND(kblight, command_kblight,
 			NULL);
 
 /*****************************************************************************/
-/* Initialization */
+/* Host commands */
+
+int pwm_command_get_fan_target_rpm(struct host_cmd_handler_args *args)
+{
+	struct ec_response_pwm_get_fan_rpm *r = args->response;
+
+	r->rpm = pwm_get_fan_target_rpm();
+	args->response_size = sizeof(*r);
+
+	return EC_RES_SUCCESS;
+}
+DECLARE_HOST_COMMAND(EC_CMD_PWM_GET_FAN_TARGET_RPM,
+		     pwm_command_get_fan_target_rpm,
+		     EC_VER_MASK(0));
+
+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_control_fan(0);
+#endif
+	pwm_set_rpm_mode(1);
+	pwm_set_fan_target_rpm(p->rpm);
+
+	return EC_RES_SUCCESS;
+}
+DECLARE_HOST_COMMAND(EC_CMD_PWM_SET_FAN_TARGET_RPM,
+		     pwm_command_set_fan_target_rpm,
+		     EC_VER_MASK(0));
+
+int pwm_command_fan_duty(struct host_cmd_handler_args *args)
+{
+	const struct ec_params_pwm_set_fan_duty *p = args->params;
+	pwm_set_fan_duty(p->percent);
+
+	return EC_RES_SUCCESS;
+}
+DECLARE_HOST_COMMAND(EC_CMD_PWM_SET_FAN_DUTY,
+		     pwm_command_fan_duty,
+		     EC_VER_MASK(0));
+
+int pwm_command_get_keyboard_backlight(struct host_cmd_handler_args *args)
+{
+	struct ec_response_pwm_get_keyboard_backlight *r = args->response;
+
+	r->percent = pwm_get_keyboard_backlight();
+	r->enabled = pwm_get_keyboard_backlight_enabled();
+	args->response_size = sizeof(*r);
+
+	return EC_RES_SUCCESS;
+}
+DECLARE_HOST_COMMAND(EC_CMD_PWM_GET_KEYBOARD_BACKLIGHT,
+		     pwm_command_get_keyboard_backlight,
+		     EC_VER_MASK(0));
+
+int pwm_command_set_keyboard_backlight(struct host_cmd_handler_args *args)
+{
+	const struct ec_params_pwm_set_keyboard_backlight *p = args->params;
+
+	pwm_set_keyboard_backlight(p->percent);
+
+	return EC_RES_SUCCESS;
+}
+DECLARE_HOST_COMMAND(EC_CMD_PWM_SET_KEYBOARD_BACKLIGHT,
+		     pwm_command_set_keyboard_backlight,
+		     EC_VER_MASK(0));
+
+/*****************************************************************************/
+/* Hooks */
 
 static void pwm_init(void)
 {
@@ -368,8 +430,8 @@ static void pwm_init(void)
 		pwm_set_keyboard_backlight(0);
 
 		/*
-		 * Enable keyboard backlight.  Fan will be enabled later by whatever
-		 * controls the fan power supply.
+		 * Enable keyboard backlight.  Fan will be enabled later by
+		 * whatever controls the fan power supply.
 		 */
 		pwm_enable_keyboard_backlight(1);
 	}
diff --git a/common/build.mk b/common/build.mk
index 6de477c458..62891da7ec 100644
--- a/common/build.mk
+++ b/common/build.mk
@@ -27,7 +27,6 @@ common-$(CONFIG_TASK_HOSTCMD)+=host_command.o host_event_commands.o
 common-$(CONFIG_TASK_I8042CMD)+=i8042.o keyboard.o
 common-$(CONFIG_TASK_LIGHTBAR)+=lightbar.o
 common-$(CONFIG_TASK_POWERSTATE)+=charge_state.o battery_precharge.o
-common-$(CONFIG_TASK_PWM)+=pwm_commands.o
 common-$(CONFIG_TASK_TEMPSENSOR)+=temp_sensor.o temp_sensor_commands.o
 common-$(CONFIG_TASK_THERMAL)+=thermal.o thermal_commands.o
 common-$(CONFIG_TASK_VBOOTHASH)+=sha256.o vboot_hash.o
diff --git a/common/pwm_commands.c b/common/pwm_commands.c
deleted file mode 100644
index 40543623e2..0000000000
--- a/common/pwm_commands.c
+++ /dev/null
@@ -1,77 +0,0 @@
-/* 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.
- */
-
-/* PWM host commands for Chrome EC */
-
-#include "host_command.h"
-#include "pwm.h"
-#include "thermal.h"
-
-
-int pwm_command_get_fan_target_rpm(struct host_cmd_handler_args *args)
-{
-	struct ec_response_pwm_get_fan_rpm *r = args->response;
-
-	r->rpm = pwm_get_fan_target_rpm();
-	args->response_size = sizeof(*r);
-
-	return EC_RES_SUCCESS;
-}
-DECLARE_HOST_COMMAND(EC_CMD_PWM_GET_FAN_TARGET_RPM,
-		     pwm_command_get_fan_target_rpm,
-		     EC_VER_MASK(0));
-
-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_control_fan(0);
-#endif
-	pwm_set_rpm_mode(1);
-	pwm_set_fan_target_rpm(p->rpm);
-
-	return EC_RES_SUCCESS;
-}
-DECLARE_HOST_COMMAND(EC_CMD_PWM_SET_FAN_TARGET_RPM,
-		     pwm_command_set_fan_target_rpm,
-		     EC_VER_MASK(0));
-
-int pwm_command_fan_duty(struct host_cmd_handler_args *args)
-{
-	const struct ec_params_pwm_set_fan_duty *p = args->params;
-	pwm_set_fan_duty(p->percent);
-
-	return EC_RES_SUCCESS;
-}
-DECLARE_HOST_COMMAND(EC_CMD_PWM_SET_FAN_DUTY,
-		     pwm_command_fan_duty,
-		     EC_VER_MASK(0));
-
-int pwm_command_get_keyboard_backlight(struct host_cmd_handler_args *args)
-{
-	struct ec_response_pwm_get_keyboard_backlight *r = args->response;
-
-	r->percent = pwm_get_keyboard_backlight();
-	r->enabled = pwm_get_keyboard_backlight_enabled();
-	args->response_size = sizeof(*r);
-
-	return EC_RES_SUCCESS;
-}
-DECLARE_HOST_COMMAND(EC_CMD_PWM_GET_KEYBOARD_BACKLIGHT,
-		     pwm_command_get_keyboard_backlight,
-		     EC_VER_MASK(0));
-
-int pwm_command_set_keyboard_backlight(struct host_cmd_handler_args *args)
-{
-	const struct ec_params_pwm_set_keyboard_backlight *p = args->params;
-
-	pwm_set_keyboard_backlight(p->percent);
-
-	return EC_RES_SUCCESS;
-}
-DECLARE_HOST_COMMAND(EC_CMD_PWM_SET_KEYBOARD_BACKLIGHT,
-		     pwm_command_set_keyboard_backlight,
-		     EC_VER_MASK(0));
diff --git a/include/pwm.h b/include/pwm.h
index 1def4f6172..62faadea5b 100644
--- a/include/pwm.h
+++ b/include/pwm.h
@@ -10,9 +10,12 @@
 
 #include "common.h"
 
-/* Enable/disable the fan.  This should be called by whatever function
- * enables the power supply to the fan. */
-int pwm_enable_fan(int enable);
+/**
+ * Enable/disable the fan.
+ *
+ * Should be called by whatever function enables the power supply to the fan.
+ */
+void pwm_enable_fan(int enable);
 
 /**
  * Enable/disable fan RPM control logic.
@@ -22,28 +25,46 @@ int pwm_enable_fan(int enable);
  */
 void pwm_set_rpm_mode(int enable);
 
-/* Get the current fan RPM. */
+/**
+ * Get the current fan RPM.
+ */
 int pwm_get_fan_rpm(void);
 
-/* Get the target fan RPM. */
+/**
+ * Get the target fan RPM.
+ */
 int pwm_get_fan_target_rpm(void);
 
-/* Set the target fan RPM.  Pass -1 to set fan to maximum. */
-int pwm_set_fan_target_rpm(int rpm);
+/**
+ * Set the target fan RPM.
+ *
+ * @param rpm   Target RPM; pass -1 to set fan to maximum.
+ */
+void pwm_set_fan_target_rpm(int rpm);
 
-/* Set the fan PWM duty cycle (0-100), disabling the automatic control. */
-int pwm_set_fan_duty(int percent);
+/**
+ * Set the fan PWM duty cycle (0-100), disabling the automatic control.
+ */
+void pwm_set_fan_duty(int percent);
 
-/* Enable/disable the keyboard backlight. */
-int pwm_enable_keyboard_backlight(int enable);
+/**
+ * Enable/disable the keyboard backlight.
+ */
+void pwm_enable_keyboard_backlight(int enable);
 
-/* Get the keyboard backlight enable/disable status (1=enabled, 0=disabled). */
+/**
+ * Get the keyboard backlight enable/disable status (1=enabled, 0=disabled).
+ */
 int pwm_get_keyboard_backlight_enabled(void);
 
-/* Get the keyboard backlight percentage (0=off, 100=max). */
+/**
+ * Get the keyboard backlight percentage (0=off, 100=max).
+ */
 int pwm_get_keyboard_backlight(void);
 
-/* Set the keyboard backlight percentage (0=off, 100=max). */
-int pwm_set_keyboard_backlight(int percent);
+/**
+ * Set the keyboard backlight percentage (0=off, 100=max).
+ */
+void pwm_set_keyboard_backlight(int percent);
 
 #endif  /* __CROS_EC_PWM_H */