iicbus: Import from FreeBSD

1 files changed, 378 insertions, 0 deletions

diff --git a/freebsd/sys/dev/iicbus/iicbus.c b/freebsd/sys/dev/iicbus/iicbus.c
new file mode 100644
index 00000000..d1e55483
--- /dev/null
+++ b/freebsd/sys/dev/iicbus/iicbus.c
@@ -0,0 +1,378 @@
+#include <machine/rtems-bsd-kernel-space.h>
+
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+ *
+ * Copyright (c) 1998, 2001 Nicolas Souchu
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+/*
+ * Autoconfiguration and support routines for the Philips serial I2C bus
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/module.h>
+#include <sys/mutex.h>
+#include <sys/rman.h>
+#include <sys/sysctl.h>
+#include <sys/bus.h>
+
+#include <dev/iicbus/iiconf.h>
+#include <dev/iicbus/iicbus.h>
+
+#include <rtems/bsd/local/iicbus_if.h>
+
+/* See comments below for why auto-scanning is a bad idea. */
+#define SCAN_IICBUS 0
+
+static int
+iicbus_probe(device_t dev)
+{
+
+	device_set_desc(dev, "Philips I2C bus");
+
+	/* Allow other subclasses to override this driver. */
+	return (BUS_PROBE_GENERIC);
+}
+
+#if SCAN_IICBUS
+static int
+iic_probe_device(device_t dev, u_char addr)
+{
+	int count;
+	char byte;
+
+	if ((addr & 1) == 0) {
+		/* is device writable? */
+		if (!iicbus_start(dev, (u_char)addr, 0)) {
+			iicbus_stop(dev);
+			return (1);
+		}
+	} else {
+		/* is device readable? */
+		if (!iicbus_block_read(dev, (u_char)addr, &byte, 1, &count))
+			return (1);
+	}
+
+	return (0);
+}
+#endif
+
+/*
+ * We add all the devices which we know about.
+ * The generic attach routine will attach them if they are alive.
+ */
+static int
+iicbus_attach(device_t dev)
+{
+#if SCAN_IICBUS
+	unsigned char addr;
+#endif
+	struct iicbus_softc *sc = IICBUS_SOFTC(dev);
+	int strict;
+
+	sc->dev = dev;
+	mtx_init(&sc->lock, "iicbus", NULL, MTX_DEF);
+	iicbus_init_frequency(dev, 0);
+	iicbus_reset(dev, IIC_FASTEST, 0, NULL);
+	if (resource_int_value(device_get_name(dev),
+		device_get_unit(dev), "strict", &strict) == 0)
+		sc->strict = strict;
+	else
+		sc->strict = 1;
+
+	/* device probing is meaningless since the bus is supposed to be
+	 * hot-plug. Moreover, some I2C chips do not appreciate random
+	 * accesses like stop after start to fast, reads for less than
+	 * x bytes...
+	 */
+#if SCAN_IICBUS
+	printf("Probing for devices on iicbus%d:", device_get_unit(dev));
+
+	/* probe any devices */
+	for (addr = 16; addr < 240; addr++) {
+		if (iic_probe_device(dev, (u_char)addr)) {
+			printf(" <%x>", addr);
+		}
+	}
+	printf("\n");
+#endif
+	bus_generic_probe(dev);
+	bus_enumerate_hinted_children(dev);
+	bus_generic_attach(dev);
+        return (0);
+}
+
+static int
+iicbus_detach(device_t dev)
+{
+	struct iicbus_softc *sc = IICBUS_SOFTC(dev);
+
+	iicbus_reset(dev, IIC_FASTEST, 0, NULL);
+	bus_generic_detach(dev);
+	device_delete_children(dev);
+	mtx_destroy(&sc->lock);
+	return (0);
+}
+
+static int
+iicbus_print_child(device_t dev, device_t child)
+{
+	struct iicbus_ivar *devi = IICBUS_IVAR(child);
+	int retval = 0;
+
+	retval += bus_print_child_header(dev, child);
+	if (devi->addr != 0)
+		retval += printf(" at addr %#x", devi->addr);
+	resource_list_print_type(&devi->rl, "irq", SYS_RES_IRQ, "%jd");
+	retval += bus_print_child_footer(dev, child);
+
+	return (retval);
+}
+
+static void
+iicbus_probe_nomatch(device_t bus, device_t child)
+{
+	struct iicbus_ivar *devi = IICBUS_IVAR(child);
+
+	device_printf(bus, "<unknown card> at addr %#x\n", devi->addr);
+}
+
+static int
+iicbus_child_location_str(device_t bus, device_t child, char *buf,
+    size_t buflen)
+{
+	struct iicbus_ivar *devi = IICBUS_IVAR(child);
+
+	snprintf(buf, buflen, "addr=%#x", devi->addr);
+	return (0);
+}
+
+static int
+iicbus_child_pnpinfo_str(device_t bus, device_t child, char *buf,
+    size_t buflen)
+{
+	*buf = '\0';
+	return (0);
+}
+
+static int
+iicbus_read_ivar(device_t bus, device_t child, int which, uintptr_t *result)
+{
+	struct iicbus_ivar *devi = IICBUS_IVAR(child);
+
+	switch (which) {
+	default:
+		return (EINVAL);
+	case IICBUS_IVAR_ADDR:
+		*result = devi->addr;
+		break;
+	case IICBUS_IVAR_NOSTOP:
+		*result = devi->nostop;
+		break;
+	}
+	return (0);
+}
+
+static int
+iicbus_write_ivar(device_t bus, device_t child, int which, uintptr_t value)
+{
+	struct iicbus_ivar *devi = IICBUS_IVAR(child);
+
+	switch (which) {
+	default:
+		return (EINVAL);
+	case IICBUS_IVAR_ADDR:
+		if (devi->addr != 0)
+			return (EINVAL);
+		devi->addr = value;
+	case IICBUS_IVAR_NOSTOP:
+		devi->nostop = value;
+		break;
+	}
+	return (0);
+}
+
+static device_t
+iicbus_add_child(device_t dev, u_int order, const char *name, int unit)
+{
+	device_t child;
+	struct iicbus_ivar *devi;
+
+	child = device_add_child_ordered(dev, order, name, unit);
+	if (child == NULL)
+		return (child);
+	devi = malloc(sizeof(struct iicbus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO);
+	if (devi == NULL) {
+		device_delete_child(dev, child);
+		return (0);
+	}
+	resource_list_init(&devi->rl);
+	device_set_ivars(child, devi);
+	return (child);
+}
+
+static void
+iicbus_hinted_child(device_t bus, const char *dname, int dunit)
+{
+	device_t child;
+	int irq;
+	struct iicbus_ivar *devi;
+
+	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
+	devi = IICBUS_IVAR(child);
+	resource_int_value(dname, dunit, "addr", &devi->addr);
+	if (resource_int_value(dname, dunit, "irq", &irq) == 0) {
+		if (bus_set_resource(child, SYS_RES_IRQ, 0, irq, 1) != 0)
+			device_printf(bus,
+			    "warning: bus_set_resource() failed\n");
+	}
+}
+
+static struct resource_list *
+iicbus_get_resource_list(device_t bus __unused, device_t child)
+{
+	struct iicbus_ivar *devi;
+
+	devi = IICBUS_IVAR(child);
+	return (&devi->rl);
+}
+
+int
+iicbus_generic_intr(device_t dev, int event, char *buf)
+{
+
+	return (0);
+}
+
+int
+iicbus_null_callback(device_t dev, int index, caddr_t data)
+{
+
+	return (0);
+}
+
+int
+iicbus_null_repeated_start(device_t dev, u_char addr)
+{
+
+	return (IIC_ENOTSUPP);
+}
+
+void
+iicbus_init_frequency(device_t dev, u_int bus_freq)
+{
+	struct iicbus_softc *sc = IICBUS_SOFTC(dev);
+
+	/*
+	 * If a bus frequency value was passed in, use it.  Otherwise initialize
+	 * it first to the standard i2c 100KHz frequency, then override that
+	 * from a hint if one exists.
+	 */
+	if (bus_freq > 0)
+		sc->bus_freq = bus_freq;
+	else {
+		sc->bus_freq = 100000;
+		resource_int_value(device_get_name(dev), device_get_unit(dev),
+		    "frequency", (int *)&sc->bus_freq);
+	}
+	/*
+	 * Set up the sysctl that allows the bus frequency to be changed.
+	 * It is flagged as a tunable so that the user can set the value in
+	 * loader(8), and that will override any other setting from any source.
+	 * The sysctl tunable/value is the one most directly controlled by the
+	 * user and thus the one that always takes precedence.
+	 */
+	SYSCTL_ADD_UINT(device_get_sysctl_ctx(dev),
+	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
+	    OID_AUTO, "frequency", CTLFLAG_RW | CTLFLAG_TUN, &sc->bus_freq,
+	    sc->bus_freq, "Bus frequency in Hz");
+}
+
+static u_int
+iicbus_get_frequency(device_t dev, u_char speed)
+{
+	struct iicbus_softc *sc = IICBUS_SOFTC(dev);
+
+	/*
+	 * If the frequency has not been configured for the bus, or the request
+	 * is specifically for SLOW speed, use the standard 100KHz rate, else
+	 * use the configured bus speed.
+	 */
+	if (sc->bus_freq == 0 || speed == IIC_SLOW)
+		return (100000);
+	return (sc->bus_freq);
+}
+
+static device_method_t iicbus_methods[] = {
+	/* device interface */
+	DEVMETHOD(device_probe,		iicbus_probe),
+	DEVMETHOD(device_attach,	iicbus_attach),
+	DEVMETHOD(device_detach,	iicbus_detach),
+
+	/* bus interface */
+	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
+	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
+	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
+	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
+	DEVMETHOD(bus_adjust_resource,	bus_generic_adjust_resource),
+	DEVMETHOD(bus_alloc_resource,	bus_generic_rl_alloc_resource),
+	DEVMETHOD(bus_get_resource,	bus_generic_rl_get_resource),
+	DEVMETHOD(bus_release_resource, bus_generic_rl_release_resource),
+	DEVMETHOD(bus_set_resource,	bus_generic_rl_set_resource),
+	DEVMETHOD(bus_get_resource_list, iicbus_get_resource_list),
+	DEVMETHOD(bus_add_child,	iicbus_add_child),
+	DEVMETHOD(bus_print_child,	iicbus_print_child),
+	DEVMETHOD(bus_probe_nomatch,	iicbus_probe_nomatch),
+	DEVMETHOD(bus_read_ivar,	iicbus_read_ivar),
+	DEVMETHOD(bus_write_ivar,	iicbus_write_ivar),
+	DEVMETHOD(bus_child_pnpinfo_str, iicbus_child_pnpinfo_str),
+	DEVMETHOD(bus_child_location_str, iicbus_child_location_str),
+	DEVMETHOD(bus_hinted_child,	iicbus_hinted_child),
+
+	/* iicbus interface */
+	DEVMETHOD(iicbus_transfer,	iicbus_transfer),
+	DEVMETHOD(iicbus_get_frequency,	iicbus_get_frequency),
+
+	DEVMETHOD_END
+};
+
+driver_t iicbus_driver = {
+        "iicbus",
+        iicbus_methods,
+        sizeof(struct iicbus_softc),
+};
+
+devclass_t iicbus_devclass;
+
+MODULE_VERSION(iicbus, IICBUS_MODVER);
+DRIVER_MODULE(iicbus, iichb, iicbus_driver, iicbus_devclass, 0, 0);