csa: Use pci_find_device to simplify clkrun_hack

Reviewed by:	christos, imp
Differential Revision:	https://reviews.freebsd.org/D47222

sys/dev/sound/pci/csa.c

@@ -108,46 +108,25 @@ static int
 clkrun_hack(int run)
 {
 #ifdef __i386__
-	devclass_t		pci_devclass;
-	device_t		*pci_devices, *pci_children, *busp, *childp;
-	int			pci_count = 0, pci_childcount = 0;
-	int			i, j, port;
+	device_t		child;
+	int			port;
 	u_int16_t		control;
 	bus_space_tag_t		btag;
 
-	if ((pci_devclass = devclass_find("pci")) == NULL) {
-		return ENXIO;
-	}
+	child = pci_find_device(0x8086, 0x7113);
+	if (child == NULL)
+		return (ENXIO);
 
-	devclass_get_devices(pci_devclass, &pci_devices, &pci_count);
-
-	for (i = 0, busp = pci_devices; i < pci_count; i++, busp++) {
-		pci_childcount = 0;
-		if (device_get_children(*busp, &pci_children, &pci_childcount))
-			continue;
-		for (j = 0, childp = pci_children; j < pci_childcount; j++, childp++) {
-			if (pci_get_vendor(*childp) == 0x8086 && pci_get_device(*childp) == 0x7113) {
-				port = (pci_read_config(*childp, 0x41, 1) << 8) + 0x10;
-				/* XXX */
-				btag = X86_BUS_SPACE_IO;
-
-				control = bus_space_read_2(btag, 0x0, port);
-				control &= ~0x2000;
-				control |= run? 0 : 0x2000;
-				bus_space_write_2(btag, 0x0, port, control);
-				free(pci_devices, M_TEMP);
-				free(pci_children, M_TEMP);
-				return 0;
-			}
-		}
-		free(pci_children, M_TEMP);
-	}
+	port = (pci_read_config(child, 0x41, 1) << 8) + 0x10;
+	/* XXX */
+	btag = X86_BUS_SPACE_IO;
 
-	free(pci_devices, M_TEMP);
-	return ENXIO;
-#else
-	return 0;
+	control = bus_space_read_2(btag, 0x0, port);
+	control &= ~0x2000;
+	control |= run? 0 : 0x2000;
+	bus_space_write_2(btag, 0x0, port, control);
 #endif
+	return (0);
 }
 
 static struct csa_card cards_4610[] = {