Add support for the PCA9546 I2C switch to pcamux(4). In comparison to

PCA9548, this variant supports only 4 instead of 8 channels.

ok kettenis@

3 files changed, 21 insertions, 12 deletions

diff --git a/share/man/man4/iic.4 b/share/man/man4/iic.4
index bc98894f559..b5c3f81db2b 100644
--- a/share/man/man4/iic.4
+++ b/share/man/man4/iic.4
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: iic.4,v 1.112 2020/06/18 20:39:28 jmc Exp $
+.\"	$OpenBSD: iic.4,v 1.113 2020/09/29 13:59:22 patrick Exp $
 .\"
 .\" Copyright (c) 2004, 2006 Alexander Yurchenko <grange@openbsd.org>
 .\"
@@ -14,7 +14,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: June 18 2020 $
+.Dd $Mdocdate: September 29 2020 $
 .Dt IIC 4
 .Os
 .Sh NAME
@@ -220,7 +220,7 @@ Philips PCA955[4567] GPIO controller
 .It Xr pcaled 4
 Philips PCA9532/9552 GPIO LED dimmer
 .It Xr pcamux 4
-Philips PCA9548 I2C switch
+Philips PCA954[68] I2C switch
 .It Xr pcfadc 4
 Philips PCF8591 temperature sensor
 .It Xr pcfrtc 4
diff --git a/share/man/man4/pcamux.4 b/share/man/man4/pcamux.4
index 2ff2b1fc511..82eda7cc9f2 100644
--- a/share/man/man4/pcamux.4
+++ b/share/man/man4/pcamux.4
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: pcamux.4,v 1.2 2020/06/18 20:39:28 jmc Exp $
+.\"	$OpenBSD: pcamux.4,v 1.3 2020/09/29 13:59:22 patrick Exp $
 .\"
 .\" Copyright (c) 2020 Mark Kettenis <kettenis@openbsd.org>
 .\"
@@ -14,19 +14,19 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: June 18 2020 $
+.Dd $Mdocdate: September 29 2020 $
 .Dt PCAMUX 4
 .Os
 .Sh NAME
 .Nm pcamux
-.Nd Philips PCA9548 I2C switch
+.Nd Philips PCA954[68] I2C switch
 .Sh SYNOPSIS
 .Cd "pcamux* at iic?"
 .Cd "iic* at pcamux?"
 .Sh DESCRIPTION
 The
 .Nm
-driver provides support for the Philips PCA9548 I2C switch,
+driver provides support for the Philips PCA954[68] I2C switch,
 which is used with the
 .Xr iic 4
 framework.
diff --git a/sys/dev/i2c/pca9548.c b/sys/dev/i2c/pca9548.c
index 1fe6328f5c2..f4320a9f985 100644
--- a/sys/dev/i2c/pca9548.c
+++ b/sys/dev/i2c/pca9548.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pca9548.c,v 1.2 2020/09/29 13:50:54 patrick Exp $	*/
+/*	$OpenBSD: pca9548.c,v 1.3 2020/09/29 13:59:22 patrick Exp $	*/
 
 /*
  * Copyright (c) 2020 Mark Kettenis
@@ -28,7 +28,9 @@
 #include <dev/ofw/openfirm.h>
 #include <dev/ofw/ofw_misc.h>
 
+#define PCA9546_NUM_CHANNELS	4
 #define PCA9548_NUM_CHANNELS	8
+#define PCAMUX_MAX_CHANNELS	8
 
 struct pcamux_bus {
 	struct pcamux_softc	*pb_sc;
@@ -45,7 +47,8 @@ struct pcamux_softc {
 	
 	int			sc_node;
 	int			sc_channel;
-	struct pcamux_bus	sc_bus[PCA9548_NUM_CHANNELS];
+	int			sc_nchannel;
+	struct pcamux_bus	sc_bus[PCAMUX_MAX_CHANNELS];
 	struct rwlock		sc_lock;
 };
 
@@ -71,7 +74,8 @@ pcamux_match(struct device *parent, void *match, void *aux)
 {
 	struct i2c_attach_args *ia = aux;
 
-	if (strcmp(ia->ia_name, "nxp,pca9548") == 0)
+	if (strcmp(ia->ia_name, "nxp,pca9546") == 0 ||
+	    strcmp(ia->ia_name, "nxp,pca9548") == 0)
 		return (1);
 	return (0);
 }
@@ -90,6 +94,11 @@ pcamux_attach(struct device *parent, struct device *self, void *aux)
 	sc->sc_channel = -1;	/* unknown */
 	rw_init(&sc->sc_lock, sc->sc_dev.dv_xname);
 
+	if (strcmp(ia->ia_name, "nxp,pca9546") == 0)
+		sc->sc_nchannel = 4;
+	else if (strcmp(ia->ia_name, "nxp,pca9548") == 0)
+		sc->sc_nchannel = 8;
+
 	printf("\n");
 
 	for (node = OF_child(node); node; node = OF_peer(node)) {
@@ -98,7 +107,7 @@ pcamux_attach(struct device *parent, struct device *self, void *aux)
 		uint32_t channel;
 
 		channel = OF_getpropint(node, "reg", -1);
-		if (channel >= PCA9548_NUM_CHANNELS)
+		if (channel >= sc->sc_nchannel)
 			continue;
 
 		pb = &sc->sc_bus[channel];
@@ -131,7 +140,7 @@ pcamux_set_channel(struct pcamux_softc *sc, int channel, int flags)
 	uint8_t data;
 	int error;
 
-	if (channel < -1 || channel >= PCA9548_NUM_CHANNELS)
+	if (channel < -1 || channel >= sc->sc_nchannel)
 		return ENXIO;
 
 	if (sc->sc_channel == channel)