Module Name: src
Committed By: jdc
Date: Thu Oct 29 06:55:51 UTC 2020
Modified Files:
src/sys/dev/i2c: files.i2c
Added Files:
src/sys/dev/i2c: pcf8574.c
Log Message:
Add a driver for the PCF8574 I/O expander, used as a GPIO in some sparc64
hardware.
The driver currently handles pins configured as LED or INDICATOR and adds
them to the LED and sysmon_envsys subsystems, respectively.
To generate a diff of this commit:
cvs rdiff -u -r1.111 -r1.112 src/sys/dev/i2c/files.i2c
cvs rdiff -u -r0 -r1.1 src/sys/dev/i2c/pcf8574.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/i2c/files.i2c
diff -u src/sys/dev/i2c/files.i2c:1.111 src/sys/dev/i2c/files.i2c:1.112
--- src/sys/dev/i2c/files.i2c:1.111 Fri Apr 24 12:38:31 2020
+++ src/sys/dev/i2c/files.i2c Thu Oct 29 06:55:51 2020
@@ -1,4 +1,4 @@
-# $NetBSD: files.i2c,v 1.111 2020/04/24 12:38:31 macallan Exp $
+# $NetBSD: files.i2c,v 1.112 2020/10/29 06:55:51 jdc Exp $
obsolete defflag opt_i2cbus.h I2C_SCAN
define i2cbus { }
@@ -395,3 +395,8 @@ file dev/i2c/cwfg.c cwfg
device pcagpio: leds
attach pcagpio at iic
file dev/i2c/pcagpio.c pcagpio
+
+# Philips PCF8574 IO expander
+device pcf8574io: leds, sysmon_envsys
+attach pcf8574io at iic
+file dev/i2c/pcf8574.c pcf8574io
Added files:
Index: src/sys/dev/i2c/pcf8574.c
diff -u /dev/null src/sys/dev/i2c/pcf8574.c:1.1
--- /dev/null Thu Oct 29 06:55:51 2020
+++ src/sys/dev/i2c/pcf8574.c Thu Oct 29 06:55:51 2020
@@ -0,0 +1,328 @@
+/*-
+ * Copyright (c) 2020 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Julian Coleman.
+ *
+ * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
+ */
+
+/*
+ * A driver for Philips Semiconductor (NXP) PCF8574/PCF857A GPIO's.
+ * Uses device properties to connect pins to the appropriate subsystem.
+ */
+
+#include <sys/cdefs.h>
+__KERNEL_RCSID(0, "$NetBSD: pcf8574.c,v 1.1 2020/10/29 06:55:51 jdc Exp $");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/device.h>
+#include <sys/kernel.h>
+
+#include <dev/sysmon/sysmonvar.h>
+
+#include <dev/i2c/i2cvar.h>
+#include <dev/led.h>
+
+#ifdef PCF8574_DEBUG
+#define DPRINTF printf
+#else
+#define DPRINTF if (0) printf
+#endif
+
+struct pcf8574_led {
+ void *cookie;
+ uint8_t mask, v_on, v_off;
+};
+
+#define PCF8574_NPINS 8
+struct pcf8574_softc {
+ device_t sc_dev;
+ i2c_tag_t sc_tag;
+ i2c_addr_t sc_addr;
+ uint8_t sc_state;
+ uint8_t sc_mask;
+
+ int sc_nleds;
+ struct pcf8574_led sc_leds[PCF8574_NPINS];
+
+ struct sysmon_envsys *sc_sme;
+ envsys_data_t sc_sensor[PCF8574_NPINS];
+ int sc_pin_sensor[PCF8574_NPINS];
+ int sc_pin_active[PCF8574_NPINS];
+
+#ifdef PCF8574_DEBUG
+ callout_t sc_timer;
+#endif
+};
+
+static int pcf8574_match(device_t, cfdata_t, void *);
+static void pcf8574_attach(device_t, device_t, void *);
+static int pcf8574_detach(device_t, int);
+
+static int pcf8574_read(struct pcf8574_softc *sc, uint8_t *val);
+static int pcf8574_write(struct pcf8574_softc *sc, uint8_t val);
+static void pcf8574_attach_led(
+ struct pcf8574_softc *, char *, int, int, int);
+void pcf8574_refresh(struct sysmon_envsys *, envsys_data_t *);
+int pcf8574_get_led(void *);
+void pcf8574_set_led(void *, int);
+
+#ifdef PCF8574_DEBUG
+static void pcf8574_timeout(void *);
+#endif
+
+CFATTACH_DECL_NEW(pcf8574io, sizeof(struct pcf8574_softc),
+ pcf8574_match, pcf8574_attach, pcf8574_detach, NULL);
+
+static const struct device_compatible_entry compat_data[] = {
+ { "i2c-pcf8574", 0 },
+ { NULL, 0 }
+};
+
+static int
+pcf8574_match(device_t parent, cfdata_t cf, void *aux)
+{
+ struct i2c_attach_args *ia = aux;
+ int match_result;
+
+ if (iic_use_direct_match(ia, cf, compat_data, &match_result))
+ return match_result;
+
+ /* We don't support indirect matches */
+ return 0;
+}
+
+static void
+pcf8574_attach(device_t parent, device_t self, void *aux)
+{
+ struct pcf8574_softc *sc = device_private(self);
+ struct i2c_attach_args *ia = aux;
+ prop_dictionary_t dict = device_properties(self);
+ prop_array_t pins;
+ prop_dictionary_t pin;
+ int i, num, def, envc = 0;
+ char name[32];
+ const char *nptr = NULL, *spptr;
+ bool ok = TRUE, act, sysmon = FALSE;
+
+ sc->sc_tag = ia->ia_tag;
+ sc->sc_addr = ia->ia_addr;
+ sc->sc_dev = self;
+
+ /*
+ * The PCF8574 requires input pins to be written with the value 1,
+ * and then read. Assume that all pins are input initially.
+ * We'll use the mask when we write, because we have to write a
+ * value for every pin, and we don't want to change input pins.
+ */
+ sc->sc_mask = 0xff;
+
+ pcf8574_read(sc, &sc->sc_state);
+
+#ifdef PCF8574_DEBUG
+ aprint_normal(": GPIO: state = 0x%02x\n", sc->sc_state);
+
+ callout_init(&sc->sc_timer, CALLOUT_MPSAFE);
+ callout_reset(&sc->sc_timer, hz*30, pcf8574_timeout, sc);
+#else
+ aprint_normal(": GPIO\n");
+#endif
+
+ pins = prop_dictionary_get(dict, "pins");
+ if (pins == NULL)
+ return;
+
+ for (i = 0; i < prop_array_count(pins); i++) {
+ pin = prop_array_get(pins, i);
+ ok &= prop_dictionary_get_cstring_nocopy(pin, "name", &nptr);
+ ok &= prop_dictionary_get_uint32(pin, "pin", &num);
+ ok &= prop_dictionary_get_bool(pin, "active_high", &act);
+ /* optional default state */
+ def = -1;
+ prop_dictionary_get_int32(pin, "default_state", &def);
+ if (!ok)
+ continue;
+ /* Extract pin type from the name */
+ spptr = strstr(nptr, " ");
+ if (spptr == NULL)
+ continue;
+ spptr += 1;
+ strncpy(name, spptr, 31);
+ sc->sc_pin_active[i] = act;
+ if (!strncmp(nptr, "LED ", 4)) {
+ sc->sc_mask &= ~(1 << num);
+ pcf8574_attach_led(sc, name, num, act, def);
+ }
+ if (!strncmp(nptr, "INDICATOR ", 4)) {
+ if (!sysmon) {
+ sc->sc_sme = sysmon_envsys_create();
+ sysmon = TRUE;
+ }
+ /* envsys sensor # to pin # mapping */
+ sc->sc_pin_sensor[envc] = num;
+ sc->sc_sensor[i].state = ENVSYS_SINVALID;
+ sc->sc_sensor[i].units = ENVSYS_INDICATOR;
+ strlcpy(sc->sc_sensor[i].desc, name,
+ sizeof(sc->sc_sensor[i].desc));
+ if (sysmon_envsys_sensor_attach(sc->sc_sme,
+ &sc->sc_sensor[i])) {
+ sysmon_envsys_destroy(sc->sc_sme);
+ aprint_error_dev(self,
+ "unable to attach pin %d at sysmon\n", i);
+ return;
+ }
+ DPRINTF("%s: added indicator: pin %d sensor %d (%s)\n",
+ device_xname(sc->sc_dev), num, envc, name);
+ envc++;
+ }
+ }
+
+ if (sysmon) {
+ sc->sc_sme->sme_name = device_xname(self);
+ sc->sc_sme->sme_cookie = sc;
+ sc->sc_sme->sme_refresh = pcf8574_refresh;
+ if (sysmon_envsys_register(sc->sc_sme)) {
+ aprint_error_dev(self,
+ "unable to register with sysmon\n");
+ sysmon_envsys_destroy(sc->sc_sme);
+ return;
+ }
+ }
+}
+
+static int
+pcf8574_detach(device_t self, int flags)
+{
+#ifdef PCF8574_DEBUG
+ struct pcf8574_softc *sc = device_private(self);
+
+ callout_halt(&sc->sc_timer, NULL);
+ callout_destroy(&sc->sc_timer);
+#endif
+
+ return 0;
+}
+
+static int
+pcf8574_read(struct pcf8574_softc *sc, uint8_t *val)
+{
+ int err = 0;
+
+ if ((err = iic_acquire_bus(sc->sc_tag, 0)) != 0)
+ return err;
+ err = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
+ sc->sc_addr, NULL, 0, val, 1, 0);
+ iic_release_bus(sc->sc_tag, 0);
+ return err;
+}
+
+static int
+pcf8574_write(struct pcf8574_softc *sc, uint8_t val)
+{
+ int err = 0;
+
+ if ((err = iic_acquire_bus(sc->sc_tag, 0)) != 0)
+ return err;
+ err = iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_addr,
+ &val, 1, NULL, 0, 0);
+ iic_release_bus(sc->sc_tag, 0);
+ return err;
+}
+
+static void
+pcf8574_attach_led(struct pcf8574_softc *sc, char *n, int pin, int act, int def)
+{
+ struct pcf8574_led *l;
+
+ l = &sc->sc_leds[sc->sc_nleds];
+ l->cookie = sc;
+ l->mask = 1 << pin;
+ l->v_on = act ? l->mask : 0;
+ l->v_off = act ? 0 : l->mask;
+ led_attach(n, l, pcf8574_get_led, pcf8574_set_led);
+ if (def != -1)
+ pcf8574_set_led(l, def);
+ DPRINTF("%s: attached LED: %02x %02x %02x def %d\n",
+ device_xname(sc->sc_dev), l->mask, l->v_on, l->v_off, def);
+ sc->sc_nleds++;
+}
+
+void
+pcf8574_refresh(struct sysmon_envsys *sme, envsys_data_t *edata)
+{
+ struct pcf8574_softc *sc = sme->sme_cookie;
+ int pin = sc->sc_pin_sensor[edata->sensor];
+ int act = sc->sc_pin_active[pin];
+
+ pcf8574_read(sc, &sc->sc_state);
+ if (act)
+ edata->value_cur = sc->sc_state & 1 << pin ? TRUE : FALSE;
+ else
+ edata->value_cur = sc->sc_state & 1 << pin ? FALSE : TRUE;
+ edata->state = ENVSYS_SVALID;
+}
+
+int
+pcf8574_get_led(void *cookie)
+{
+ struct pcf8574_led *l = cookie;
+ struct pcf8574_softc *sc = l->cookie;
+
+ return ((sc->sc_state & l->mask) == l->v_on);
+}
+
+void
+pcf8574_set_led(void *cookie, int val)
+{
+ struct pcf8574_led *l = cookie;
+ struct pcf8574_softc *sc = l->cookie;
+ uint32_t newstate;
+
+ newstate = sc->sc_state & ~l->mask;
+ newstate |= val ? l->v_on : l->v_off;
+ DPRINTF("%s: set LED: %02x -> %02x, %02x %02x %02x\n",
+ device_xname(sc->sc_dev), sc->sc_state, newstate, l->mask, l->v_on, l->v_off);
+ if (newstate != sc->sc_state) {
+ pcf8574_write(sc, newstate | sc->sc_mask);
+ pcf8574_read(sc, &sc->sc_state);
+ }
+}
+
+#ifdef PCF8574_DEBUG
+static void
+pcf8574_timeout(void *v)
+{
+ struct pcf8574_softc *sc = v;
+ uint8_t val;
+
+ pcf8574_read(sc, &val);
+ if (val != sc->sc_state)
+ aprint_normal_dev(sc->sc_dev,
+ "status change: 0x%02x > 0x%02x\n", sc->sc_state, val);
+ sc->sc_state = val;
+
+ callout_reset(&sc->sc_timer, hz*60, pcf8574_timeout, sc);
+}
+#endif
