diff --git a/sys/arm/allwinner/aw_pwm.c b/sys/arm/allwinner/aw_pwm.c
index 6a042e8b2cd6..aef28ac0e43f 100644
--- a/sys/arm/allwinner/aw_pwm.c
+++ b/sys/arm/allwinner/aw_pwm.c
@@ -226,7 +226,7 @@ aw_pwm_detach(device_t dev)
 }
 
 static int
-aw_pwm_channel_count(device_t dev, int *nchannel)
+aw_pwm_channel_count(device_t dev, u_int *nchannel)
 {
 
 	*nchannel = 1;
@@ -235,7 +235,7 @@ aw_pwm_channel_count(device_t dev, int *nchannel)
 }
 
 static int
-aw_pwm_channel_config(device_t dev, int channel, unsigned int period, unsigned int duty)
+aw_pwm_channel_config(device_t dev, u_int channel, u_int period, u_int duty)
 {
 	struct aw_pwm_softc *sc;
 	uint64_t period_freq, duty_freq;
@@ -298,7 +298,7 @@ aw_pwm_channel_config(device_t dev, int channel, unsigned int period, unsigned i
 }
 
 static int
-aw_pwm_channel_get_config(device_t dev, int channel, unsigned int *period, unsigned int *duty)
+aw_pwm_channel_get_config(device_t dev, u_int channel, u_int *period, u_int *duty)
 {
 	struct aw_pwm_softc *sc;
 
@@ -311,7 +311,7 @@ aw_pwm_channel_get_config(device_t dev, int channel, unsigned int *period, unsig
 }
 
 static int
-aw_pwm_channel_enable(device_t dev, int channel, bool enable)
+aw_pwm_channel_enable(device_t dev, u_int channel, bool enable)
 {
 	struct aw_pwm_softc *sc;
 	uint32_t reg;
@@ -335,7 +335,7 @@ aw_pwm_channel_enable(device_t dev, int channel, bool enable)
 }
 
 static int
-aw_pwm_channel_is_enabled(device_t dev, int channel, bool *enabled)
+aw_pwm_channel_is_enabled(device_t dev, u_int channel, bool *enabled)
 {
 	struct aw_pwm_softc *sc;
 
diff --git a/sys/dev/pwm/pwmbus.c b/sys/dev/pwm/pwmbus.c
index c9ffdddb645b..e97a119f7359 100644
--- a/sys/dev/pwm/pwmbus.c
+++ b/sys/dev/pwm/pwmbus.c
@@ -57,7 +57,7 @@ struct pwmbus_softc {
 	device_t	dev;
 	device_t	parent;
 
-	int		nchannels;
+	u_int		nchannels;
 };
 
 static int
@@ -103,43 +103,43 @@ pwmbus_detach(device_t dev)
 }
 
 static int
-pwmbus_channel_config(device_t dev, int chan, u_int period, u_int duty)
+pwmbus_channel_config(device_t dev, u_int chan, u_int period, u_int duty)
 {
 	return (PWMBUS_CHANNEL_CONFIG(device_get_parent(dev), chan, period, duty));
 }
 
 static int
-pwmbus_channel_get_config(device_t dev, int chan, u_int *period, u_int *duty)
+pwmbus_channel_get_config(device_t dev, u_int chan, u_int *period, u_int *duty)
 {
 	return (PWMBUS_CHANNEL_GET_CONFIG(device_get_parent(dev), chan, period, duty));
 }
 
 static int
-pwmbus_channel_get_flags(device_t dev, int chan, uint32_t *flags)
+pwmbus_channel_get_flags(device_t dev, u_int chan, uint32_t *flags)
 {
 	return (PWMBUS_CHANNEL_GET_FLAGS(device_get_parent(dev), chan, flags));
 }
 
 static int
-pwmbus_channel_enable(device_t dev, int chan, bool enable)
+pwmbus_channel_enable(device_t dev, u_int chan, bool enable)
 {
 	return (PWMBUS_CHANNEL_ENABLE(device_get_parent(dev), chan, enable));
 }
 
 static int
-pwmbus_channel_set_flags(device_t dev, int chan, uint32_t flags)
+pwmbus_channel_set_flags(device_t dev, u_int chan, uint32_t flags)
 {
 	return (PWMBUS_CHANNEL_SET_FLAGS(device_get_parent(dev), chan, flags));
 }
 
 static int
-pwmbus_channel_is_enabled(device_t dev, int chan, bool *enable)
+pwmbus_channel_is_enabled(device_t dev, u_int chan, bool *enable)
 {
 	return (PWMBUS_CHANNEL_IS_ENABLED(device_get_parent(dev), chan, enable));
 }
 
 static int
-pwmbus_channel_count(device_t dev, int *nchannel)
+pwmbus_channel_count(device_t dev, u_int *nchannel)
 {
 	return (PWMBUS_CHANNEL_COUNT(device_get_parent(dev), nchannel));
 }
diff --git a/sys/dev/pwm/pwmbus.h b/sys/dev/pwm/pwmbus.h
index 7251b9fc79a1..fbecce531424 100644
--- a/sys/dev/pwm/pwmbus.h
+++ b/sys/dev/pwm/pwmbus.h
@@ -34,7 +34,7 @@
 
 struct pwm_channel {
 	device_t	dev;
-	int		channel;
+	u_int		channel;
 	uint64_t	period;
 	uint64_t	duty;
 	uint32_t	flags;
diff --git a/sys/dev/pwm/pwmbus_if.m b/sys/dev/pwm/pwmbus_if.m
index b156d110969e..4e7b49bf405c 100644
--- a/sys/dev/pwm/pwmbus_if.m
+++ b/sys/dev/pwm/pwmbus_if.m
@@ -33,14 +33,14 @@ INTERFACE pwmbus;
 
 CODE {
 	static int
-	pwm_default_set_flags(device_t dev, int channel, uint32_t flags)
+	pwm_default_set_flags(device_t dev, u_int channel, uint32_t flags)
 	{
 
 		return (EOPNOTSUPP);
 	}
 
 	static int
-	pwm_default_get_flags(device_t dev, int channel, uint32_t *flags)
+	pwm_default_get_flags(device_t dev, u_int channel, uint32_t *flags)
 	{
 
 		*flags = 0;
@@ -54,7 +54,7 @@ CODE {
 #
 METHOD int channel_config {
 	device_t bus;
-	int channel;
+	u_int channel;
 	unsigned int period;
 	unsigned int duty;
 };
@@ -65,7 +65,7 @@ METHOD int channel_config {
 #
 METHOD int channel_get_config {
 	device_t bus;
-	int channel;
+	u_int channel;
 	unsigned int *period;
 	unsigned int *duty;
 };
@@ -75,7 +75,7 @@ METHOD int channel_get_config {
 #
 METHOD int channel_set_flags {
 	device_t bus;
-	int channel;
+	u_int channel;
 	uint32_t flags;
 } DEFAULT pwm_default_set_flags;
 
@@ -84,7 +84,7 @@ METHOD int channel_set_flags {
 #
 METHOD int channel_get_flags {
 	device_t dev;
-	int channel;
+	u_int channel;
 	uint32_t *flags;
 } DEFAULT pwm_default_get_flags;
 
@@ -93,7 +93,7 @@ METHOD int channel_get_flags {
 #
 METHOD int channel_enable {
 	device_t bus;
-	int channel;
+	u_int channel;
 	bool enable;
 };
 
@@ -102,7 +102,7 @@ METHOD int channel_enable {
 #
 METHOD int channel_is_enabled {
 	device_t bus;
-	int channel;
+	u_int channel;
 	bool *enabled;
 };
 
@@ -111,5 +111,5 @@ METHOD int channel_is_enabled {
 #
 METHOD int channel_count {
 	device_t bus;
-	int *nchannel;
+	u_int *nchannel;
 };
diff --git a/sys/dev/pwm/pwmc.c b/sys/dev/pwm/pwmc.c
index 2317b52981ca..18b60388a7bc 100644
--- a/sys/dev/pwm/pwmc.c
+++ b/sys/dev/pwm/pwmc.c
@@ -54,7 +54,7 @@ pwm_ioctl(struct cdev *dev, u_long cmd, caddr_t data,
 	struct pwmc_softc *sc;
 	struct pwm_state state;
 	device_t bus;
-	int nchannel;
+	u_int nchannel;
 	int rv = 0;
 
 	sc = dev->si_drv1;
@@ -62,7 +62,7 @@ pwm_ioctl(struct cdev *dev, u_long cmd, caddr_t data,
 
 	switch (cmd) {
 	case PWMMAXCHANNEL:
-		nchannel = -1;
+		nchannel = 0;
 		rv = PWMBUS_CHANNEL_COUNT(bus, &nchannel);
 		bcopy(&nchannel, data, sizeof(nchannel));
 		break;
diff --git a/usr.sbin/pwm/pwm.c b/usr.sbin/pwm/pwm.c
index 9a53e37b836d..52ea1b79e6ac 100644
--- a/usr.sbin/pwm/pwm.c
+++ b/usr.sbin/pwm/pwm.c
@@ -66,7 +66,7 @@ main(int argc, char *argv[])
 {
 	struct pwm_state state;
 	int fd;
-	int channel, nchannels;
+	u_int channel, nchannels;
 	int period, duty;
 	int action, ch;
 	cap_rights_t right_ioctl;
@@ -75,7 +75,7 @@ main(int argc, char *argv[])
 
 	action = 0;
 	fd = -1;
-	channel = -1;
+	channel = -1u;
 	period = duty = -1;
 
 	while ((ch = getopt(argc, argv, "f:c:EDCp:d:")) != -1) {
@@ -110,9 +110,9 @@ main(int argc, char *argv[])
 				usage();
 			break;
 		case 'c':
-			if (channel != -1)
+			if (channel != -1u)
 				usage();
-			channel = strtol(optarg, NULL, 10);
+			channel = strtoul(optarg, NULL, 10);
 			break;
 		case 'f':
 			if ((fd = open(optarg, O_RDWR)) < 0) {