TMP461: Add thermal sensor driver

Add driver for TMP461 thermal sensor. Register new sysctl node
of integer type for device. Read register and fill sysctl with
valid temperature.

Reviewed by:
Sponsored by:		Alstom
Obtained from:		Semihalf
Differential revision:	https://reviews.freebsd.org/D32818

sys/dev/iicbus/tmp461.c

+/*-
+ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+ *
+ * Copyright (c) 2021 Alstom Group.
+ * Copyright (c) 2021 Semihalf.
+ *
+ * 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 ``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 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("$FreeBSD$");
+
+#include "opt_platform.h"
+
+#include <sys/param.h>
+#include <sys/bus.h>
+#include <sys/module.h>
+#include <sys/ctype.h>
+#include <sys/kernel.h>
+#include <sys/libkern.h>
+#include <sys/sysctl.h>
+
+#include <dev/iicbus/iicbus.h>
+#include <dev/iicbus/iiconf.h>
+
+#include <dev/ofw/ofw_bus_subr.h>
+#include <dev/ofw/ofw_bus.h>
+
+#define BIT(x)					(1UL << (x))
+
+#define TMP461_LOCAL_TEMP_REG_MSB		0x0
+#define TMP461_LOCAL_TEMP_REG_LSB		0x15
+#define TMP461_GLOBAL_TEMP_REG_MSB		0x1
+#define TMP461_GLOBAL_TEMP_REG_LSB		0x10
+#define TMP461_CONFIG_REG			0x3
+#define TMP461_CONFIG_REG_TEMP_RANGE_BIT	BIT(2)
+
+#define TMP461_EXTENDED_TEMP_MODIFIER		64
+/* 28.4 fixed point representation of 273.15f */
+#define TMP461_C_TO_K_FIX			4370
+#define TMP461_TEMP_LSB				0
+
+static int tmp461_probe(device_t dev);
+static int tmp461_attach(device_t dev);
+static int tmp461_read_1(device_t dev, uint8_t reg, uint8_t *data);
+static int tmp461_read_temp(device_t dev, int32_t *temp);
+static int tmp461_detach(device_t dev);
+static int tmp461_sensor_sysctl(SYSCTL_HANDLER_ARGS);
+static int32_t tmp461_signed_extend32(uint32_t value, int sign_pos);
+
+static device_method_t tmp461_methods[] = {
+	DEVMETHOD(device_probe,		tmp461_probe),
+	DEVMETHOD(device_attach,	tmp461_attach),
+	DEVMETHOD(device_detach,	tmp461_detach),
+
+	DEVMETHOD_END
+};
+
+static driver_t tmp461_driver = {
+	"tmp461_dev",
+	tmp461_methods,
+	0
+};
+
+static devclass_t tmp461_devclass;
+
+static struct ofw_compat_data tmp461_compat_data[] = {
+	{ "ti,tmp461",		1 },
+	{ NULL,			0 }
+};
+
+DRIVER_MODULE(tmp461, iicbus, tmp461_driver, tmp461_devclass, 0, 0);
+IICBUS_FDT_PNP_INFO(tmp461_compat_data);
+
+static int
+tmp461_attach(device_t dev)
+{
+	struct sysctl_oid *sensor_root_oid;
+	struct sysctl_ctx_list *ctx;
+
+	ctx = device_get_sysctl_ctx(dev);
+	
+	sensor_root_oid = SYSCTL_ADD_NODE(ctx, SYSCTL_STATIC_CHILDREN(_hw),
+	    OID_AUTO, "temperature", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
+	    "TMP 461 Thermal Sensor Information");
+	if (sensor_root_oid == NULL)
+		return (ENXIO);
+
+	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(sensor_root_oid), OID_AUTO,
+	    "tmp461", CTLTYPE_INT | CTLFLAG_RD, dev, 0,
+	    tmp461_sensor_sysctl, "IK0", "TMP461 Thermal Sensor");
+
+	return (0);
+}
+
+static int
+tmp461_probe(device_t dev)
+{
+
+	if (!ofw_bus_status_okay(dev))
+		return (ENXIO);
+
+	if (!ofw_bus_search_compatible(dev, tmp461_compat_data)->ocd_data)
+		return (ENXIO);
+
+	device_set_desc(dev, "TMP461 Thermal Sensor");
+
+	return (BUS_PROBE_GENERIC);
+}
+
+static int
+tmp461_detach(device_t dev)
+{
+
+	return (0);
+}
+
+static int
+tmp461_read_1(device_t dev,  uint8_t reg, uint8_t *data)
+{
+	int error;
+
+	error = iicdev_readfrom(dev, reg, (void *) data, 1, IIC_WAIT);
+	if (error != 0)
+		device_printf(dev, "Failed to read from device\n");
+
+	return (error);
+}
+
+static int
+tmp461_read_temp(device_t dev, int32_t *temp)
+{
+	bool extended_mode;
+	uint8_t data;
+	int error;
+
+	/* read temperature range */
+	error = tmp461_read_1(dev, TMP461_CONFIG_REG, &data);
+	if (error != 0)
+		return (ENXIO);
+
+	extended_mode = data & TMP461_CONFIG_REG_TEMP_RANGE_BIT;
+
+	/* read temp MSB */
+	error = tmp461_read_1(dev, TMP461_LOCAL_TEMP_REG_MSB, &data);
+	if (error != 0)
+		return (ENXIO);
+
+	*temp = signed_extend32(data, TMP461_TEMP_LSB, 8) -
+	    (extended_mode ? TMP461_EXTENDED_TEMP_MODIFIER : 0);
+
+	error = tmp461_read_1(dev, TMP461_LOCAL_TEMP_REG_LSB, &data);
+	if (error != 0)
+		return (ENXIO);
+
+	*temp = (((*temp << 4) | (data >> 4)) + TMP461_C_TO_K_FIX) >> 4;
+
+	return (0);
+}
+
+static int
+tmp461_sensor_sysctl(SYSCTL_HANDLER_ARGS)
+{
+	device_t dev;
+	int32_t temp;
+	int error;
+
+	dev = arg1;
+
+	error = tmp461_read_temp(dev, &temp);
+	if (error != 0)
+		return (error);
+
+	return (sysctl_handle_int(oidp, &temp, 0, req));
+}
+

sys/modules/i2c/Makefile

@@ -30,7 +30,8 @@ SUBDIR = \
 
 .if !empty(OPT_FDT)
 SUBDIR += rx8803 \
-	  tca6416
+	  tca6416 \
+	  tmp461
 .endif
 
 .if ${MACHINE_CPUARCH} == "aarch64" || ${MACHINE_CPUARCH} == "amd64" || \

sys/modules/i2c/tmp461/Makefile

+# $FreeBSD$
+
+.PATH:		${SRCTOP}/sys/dev/iicbus
+KMOD		= tmp461
+SRCS		= tmp461.c bus_if.h device_if.h iicbus_if.h ofw_bus_if.h opt_platform.h
+
+.include <bsd.kmod.mk>