git: d6f71e09a789 - stable/13 - pcf8591: driver for adc/dac with i2c interface
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Date: Sat, 13 Nov 2021 09:11:05 UTC
The branch stable/13 has been updated by avg:
URL: https://cgit.FreeBSD.org/src/commit/?id=d6f71e09a789f57f28d397c032ead62dc0b09c48
commit d6f71e09a789f57f28d397c032ead62dc0b09c48
Author: Andriy Gapon <avg@FreeBSD.org>
AuthorDate: 2020-08-17 10:05:11 +0000
Commit: Andriy Gapon <avg@FreeBSD.org>
CommitDate: 2021-11-13 09:10:44 +0000
pcf8591: driver for adc/dac with i2c interface
(cherry picked from commit a60b30469741392e66ec6fd21a8d5c4810a2d407)
---
share/man/man4/Makefile | 1 +
share/man/man4/pcf8591.4 | 122 ++++++++++++++++++
sys/conf/files | 1 +
sys/dev/iicbus/pcf8591.c | 271 +++++++++++++++++++++++++++++++++++++++
sys/modules/i2c/Makefile | 1 +
sys/modules/i2c/pcf8591/Makefile | 17 +++
6 files changed, 413 insertions(+)
diff --git a/share/man/man4/Makefile b/share/man/man4/Makefile
index 2f3283e14573..e80b451f20b2 100644
--- a/share/man/man4/Makefile
+++ b/share/man/man4/Makefile
@@ -424,6 +424,7 @@ MAN= aac.4 \
pccard.4 \
pccbb.4 \
pcf.4 \
+ pcf8591.4 \
${_pchtherm.4} \
pci.4 \
pcib.4 \
diff --git a/share/man/man4/pcf8591.4 b/share/man/man4/pcf8591.4
new file mode 100644
index 000000000000..2876ad057f90
--- /dev/null
+++ b/share/man/man4/pcf8591.4
@@ -0,0 +1,122 @@
+.\"
+.\" SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+.\"
+.\" Copyright (c) 2020 Andriy Gapon <avg@FreeBSD.org>
+.\"
+.\" 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.
+.\"
+.\" $FreeBSD: head/share/man/man4/cp2112.4 364144 2020-08-12 09:42:05Z avg $
+.\"
+.Dd November 6, 2021
+.Dt PCF8591 4
+.Os
+.Sh NAME
+.Nm pcf8591
+.Nd driver for the PCF8591 8-bit A/D and D/A converter
+.Sh SYNOPSIS
+To compile this driver into the kernel,
+place the following lines in your
+kernel configuration file:
+.Bd -ragged -offset indent
+.Cd "device pcf8591"
+.Cd "device iicbus"
+.Ed
+.Pp
+Alternatively, to load the driver as a
+module at boot time, place the following line in
+.Xr loader.conf 5 :
+.Bd -literal -offset indent
+pcf8591_load="YES"
+.Ed
+.Sh DESCRIPTION
+The
+.Nm
+driver supports reading four inputs and setting one output over I2C.
+The hardware supports configuring the input lines as:
+.Bl -bullet
+.It
+four single-ended inputs
+.It
+three differential inputs (one input line is shared between all three inputs)
+.It
+two single-ended inputs and one differential input
+.It
+two differential inputs.
+.El
+.Pp
+The
+.Nm
+driver reports data via
+.Xr sysctl 8
+entries in the device's node in the
+.Xr sysctl 8
+tree:
+.Bl -tag -width inputs.%d
+.It Va inputs.%d
+The input level of the corresponding input in steps between 0 and 255.
+Absolute voltage depends on an actual reference voltage.
+.El
+.Pp
+On an
+.Xr FDT 4
+based system the following properties must be set:
+.Bl -tag -width "compatible"
+.It Va compatible
+Must be set to "nxp,pcf8591".
+.It Va reg
+The I2C address of
+.Nm .
+It should be in the range from 0x40 to 0x4f (7-bit).
+.El
+.Pp
+The DTS part for a
+.Nm
+device usually looks like:
+.Bd -literal
+/ {
+
+ ...
+ pcf8591adc {
+ compatible = "nxp,pcf8591";
+ reg = <0x48>;
+ };
+};
+.Ed
+.Sh SEE ALSO
+.Xr fdt 4 ,
+.Xr iicbus 4 ,
+.Xr sysctl 8
+.Sh HISTORY
+The
+.Nm
+driver and this manual page was written by
+.An Andriy Gapon Aq Mt avg@FreeBSD.org .
+.Sh BUGS
+The
+.Nm
+driver does not support changing the input configuration.
+All input lines are configured as single-ended inputs.
+.Pp
+The
+.Nm
+driver does not support setting the output.
+It is always disabled (tri-state).
diff --git a/sys/conf/files b/sys/conf/files
index 282a86d74347..92e68a0b103e 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -1885,6 +1885,7 @@ dev/iicbus/mux/iic_gpiomux.c optional iic_gpiomux fdt
dev/iicbus/mux/ltc430x.c optional ltc430x
dev/iicbus/nxprtc.c optional nxprtc | pcf8563
dev/iicbus/ofw_iicbus.c optional fdt iicbus
+dev/iicbus/pcf8591.c optional pcf8591
dev/iicbus/rtc8583.c optional rtc8583
dev/iicbus/rtc/rx8803.c optional rx8803 iicbus fdt
dev/iicbus/s35390a.c optional s35390a
diff --git a/sys/dev/iicbus/pcf8591.c b/sys/dev/iicbus/pcf8591.c
new file mode 100644
index 000000000000..ff769b368d91
--- /dev/null
+++ b/sys/dev/iicbus/pcf8591.c
@@ -0,0 +1,271 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) Andriy Gapon
+ *
+ * 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("$FreeBSD$");
+
+#include "opt_platform.h"
+
+#include <sys/param.h>
+#include <sys/bus.h>
+#include <sys/kernel.h>
+#include <sys/module.h>
+#include <sys/sysctl.h>
+#include <sys/systm.h>
+
+#include <machine/bus.h>
+
+#include <dev/iicbus/iicbus.h>
+#include <dev/iicbus/iiconf.h>
+
+#ifdef FDT
+#include <dev/ofw/ofw_bus.h>
+#include <dev/ofw/ofw_bus_subr.h>
+#endif
+
+/*
+ * Driver for PCF8591 I2C 8-bit ADC and DAC.
+ */
+#define CTRL_CH_SELECT_MASK 0x03
+#define CTRL_AUTOINC_EN 0x04
+#define CTRL_CH_CONFIG_MASK 0x30
+#define CTRL_CH_CONFIG_4_SINGLE 0x00
+#define CTRL_CH_CONFIG_3_DIFF 0x10
+#define CTRL_CH_CONFIG_2_SINGLE_1_DIFF 0x20
+#define CTRL_CH_CONFIG_2_DIFF 0x30
+#define CTRL_OUTPUT_EN 0x40
+
+struct pcf8591_softc {
+ device_t sc_dev;
+ int sc_ch_count;
+ uint8_t sc_addr;
+ uint8_t sc_cfg;
+ uint8_t sc_output;
+};
+
+#ifdef FDT
+static struct ofw_compat_data compat_data[] = {
+ { "nxp,pcf8591", true },
+ { NULL, false }
+};
+#endif
+
+static int
+pcf8591_set_config(device_t dev)
+{
+
+ struct iic_msg msg;
+ uint8_t data[2];
+ struct pcf8591_softc *sc;
+ int error;
+
+ sc = device_get_softc(dev);
+ data[0] = sc->sc_cfg;
+ data[1] = sc->sc_output;
+ msg.slave = sc->sc_addr;
+ msg.flags = IIC_M_WR;
+ msg.len = nitems(data);
+ msg.buf = data;
+
+ error = iicbus_transfer_excl(dev, &msg, 1, IIC_INTRWAIT);
+ return (error);
+}
+
+static int
+pcf8591_get_reading(device_t dev, uint8_t *reading)
+{
+ struct iic_msg msg;
+ struct pcf8591_softc *sc;
+ int error;
+
+ sc = device_get_softc(dev);
+
+ msg.slave = sc->sc_addr;
+ msg.flags = IIC_M_RD;
+ msg.len = 1;
+ msg.buf = reading;
+
+ error = iicbus_transfer_excl(dev, &msg, 1, IIC_INTRWAIT);
+ return (error);
+}
+
+static int
+pcf8591_select_channel(device_t dev, int channel)
+{
+ struct pcf8591_softc *sc;
+ int error;
+ uint8_t unused;
+
+ sc = device_get_softc(dev);
+ if (channel >= sc->sc_ch_count)
+ return (EINVAL);
+ sc->sc_cfg &= ~CTRL_CH_SELECT_MASK;
+ sc->sc_cfg += channel;
+ error = pcf8591_set_config(dev);
+ if (error != 0)
+ return (error);
+
+ /*
+ * The next read is still for the old channel,
+ * so do it and discard.
+ */
+ error = pcf8591_get_reading(dev, &unused);
+ return (error);
+}
+
+static int
+pcf8591_channel_sysctl(SYSCTL_HANDLER_ARGS)
+{
+ struct pcf8591_softc *sc;
+ device_t dev;
+ int error, channel, val;
+ uint8_t reading;
+
+ dev = arg1;
+ channel = arg2;
+ sc = device_get_softc(dev);
+
+ if (req->oldptr != NULL) {
+ error = pcf8591_select_channel(dev, channel);
+ if (error != 0)
+ return (EIO);
+ error = pcf8591_get_reading(dev, &reading);
+ if (error != 0)
+ return (EIO);
+ val = reading;
+ }
+ error = sysctl_handle_int(oidp, &val, 0, req);
+ return (error);
+}
+
+static void
+pcf8591_start(void *arg)
+{
+ device_t dev;
+ struct pcf8591_softc *sc;
+ struct sysctl_ctx_list *ctx;
+ struct sysctl_oid *tree_node;
+ struct sysctl_oid_list *tree;
+ struct sysctl_oid *inputs_node;
+ struct sysctl_oid_list *inputs;
+ int error;
+
+ sc = arg;
+ dev = sc->sc_dev;
+
+ /*
+ * Set initial -- and, for the time being, fixed -- configuration.
+ * Channel auto-incrementi is disabled, although it could be more
+ * performant and precise for bulk channel queries.
+ * The inputs are configured as four single channels.
+ * The output is disabled.
+ */
+ sc->sc_cfg = 0;
+ sc->sc_output = 0;
+ sc->sc_ch_count = 4;
+ error = pcf8591_set_config(dev);
+
+ ctx = device_get_sysctl_ctx(dev);
+ tree_node = device_get_sysctl_tree(dev);
+ tree = SYSCTL_CHILDREN(tree_node);
+
+ inputs_node = SYSCTL_ADD_NODE(ctx, tree, OID_AUTO, "inputs",
+ CTLTYPE_NODE, NULL, "Input channels");
+ inputs = SYSCTL_CHILDREN(inputs_node);
+ for (int i = 0; i < sc->sc_ch_count; i++) {
+ char buf[4];
+
+ snprintf(buf, sizeof(buf), "%d", i);
+ SYSCTL_ADD_PROC(ctx, inputs, OID_AUTO, buf,
+ CTLTYPE_INT | CTLFLAG_RD, dev, i,
+ pcf8591_channel_sysctl, "I", "Input level from 0 to 255 "
+ "(relative to Vref)");
+ }
+}
+
+static int
+pcf8591_probe(device_t dev)
+{
+#ifdef FDT
+ if (!ofw_bus_status_okay(dev))
+ return (ENXIO);
+#endif
+ device_set_desc(dev, "PCF8591 8-bit ADC / DAC");
+#ifdef FDT
+ if (ofw_bus_search_compatible(dev, compat_data)->ocd_data)
+ return (BUS_PROBE_GENERIC);
+#endif
+ return (BUS_PROBE_NOWILDCARD);
+}
+
+static int
+pcf8591_attach(device_t dev)
+{
+ struct pcf8591_softc *sc;
+
+ sc = device_get_softc(dev);
+ sc->sc_dev = dev;
+ sc->sc_addr = iicbus_get_addr(dev);
+
+ /*
+ * We have to wait until interrupts are enabled. Usually I2C read
+ * and write only works when the interrupts are available.
+ */
+ config_intrhook_oneshot(pcf8591_start, sc);
+ return (0);
+}
+
+static int
+pcf8591_detach(device_t dev)
+{
+ return (0);
+}
+
+static device_method_t pcf8591_methods[] = {
+ /* Device interface */
+ DEVMETHOD(device_probe, pcf8591_probe),
+ DEVMETHOD(device_attach, pcf8591_attach),
+ DEVMETHOD(device_detach, pcf8591_detach),
+
+ DEVMETHOD_END
+};
+
+static driver_t pcf8591_driver = {
+ "pcf8591",
+ pcf8591_methods,
+ sizeof(struct pcf8591_softc)
+};
+
+static devclass_t pcf8591_devclass;
+
+DRIVER_MODULE(pcf8591, iicbus, pcf8591_driver, pcf8591_devclass, 0, 0);
+MODULE_DEPEND(pcf8591, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER);
+MODULE_VERSION(pcf8591, 1);
+#ifdef FDT
+IICBUS_FDT_PNP_INFO(compat_data);
+#endif
diff --git a/sys/modules/i2c/Makefile b/sys/modules/i2c/Makefile
index edd92943c6c1..b79e2a98fc7d 100644
--- a/sys/modules/i2c/Makefile
+++ b/sys/modules/i2c/Makefile
@@ -20,6 +20,7 @@ SUBDIR = \
jedec_dimm \
mux \
nxprtc \
+ pcf8591 \
rtc8583 \
s35390a \
smb \
diff --git a/sys/modules/i2c/pcf8591/Makefile b/sys/modules/i2c/pcf8591/Makefile
new file mode 100644
index 000000000000..82148867a00f
--- /dev/null
+++ b/sys/modules/i2c/pcf8591/Makefile
@@ -0,0 +1,17 @@
+# $FreeBSD$
+
+.PATH: ${SRCTOP}/sys/dev/iicbus
+KMOD= pcf8591
+SRCS= pcf8591.c
+
+SRCS+= \
+ bus_if.h \
+ device_if.h \
+ iicbus_if.h \
+ opt_platform.h
+
+.if !empty(OPT_FDT)
+SRCS+= ofw_bus_if.h
+.endif
+
+.include <bsd.kmod.mk>