system_manager, libobmc-intf: Add power GPIO configuration interface

This adds a dbus call (in org.openbmc.managers.System) and C binding (in
libopenbmc-intf) to read a POWER_CONFIG from the Python system
configuration that abstracts GPIO functionality (power good, reset, etc)
from their net names in GPIO_CONFIG.

This should eventually replace machine-specific patches to op-pwrctl
that define their own power and reset lines.

Change-Id: I56eaaf60ef852b68124e4a765942243ad17d06ac
Signed-off-by: Xo Wang <xow@google.com>

3 files changed, 170 insertions, 2 deletions

diff --git a/libopenbmc_intf/Makefile b/libopenbmc_intf/Makefile
index cd86906..fe17dc9 100644
--- a/libopenbmc_intf/Makefile
+++ b/libopenbmc_intf/Makefile
@@ -5,7 +5,7 @@ PACKAGE_DEPS=gio-unix-2.0 glib-2.0
 SONAME=libopenbmc_intf.so
 VERSION=1
 LIBOBMC=$(SONAME).$(VERSION)
-INCLUDES=openbmc_intf.h openbmc.h gpio.h
+INCLUDES=openbmc_intf.h openbmc.h gpio.h power_gpio.h
 
 LDLIBS+=$(shell pkg-config --libs $(PACKAGE_DEPS))
 ALL_CFLAGS+=$(shell pkg-config --cflags $(PACKAGE_DEPS)) -fPIC -Werror $(CFLAGS)
@@ -18,7 +18,7 @@ all: $(SONAME)
 $(SONAME): $(LIBOBMC)
 	ln -sf $^ $@
 
-$(LIBOBMC): lib%.so.$(VERSION): %.o gpio.o
+$(LIBOBMC): lib%.so.$(VERSION): %.o gpio.o power_gpio.o
 	$(CC) -shared $(CFLAGS) $(LDFLAGS) -Wl,-soname,$(SONAME) \
 		-o $@ $^ $(LDLIBS)
 
diff --git a/libopenbmc_intf/power_gpio.c b/libopenbmc_intf/power_gpio.c
new file mode 100644
index 0000000..3f4b5a8
--- /dev/null
+++ b/libopenbmc_intf/power_gpio.c
@@ -0,0 +1,123 @@
+/**
+ * Copyright © 2016 Google Inc.
+ * Copyright © 2016 IBM Corporation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "power_gpio.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <glib.h>
+
+gboolean read_power_gpio(GDBusConnection *connection, PowerGpio *power_gpio)
+{
+	GDBusProxy *proxy;
+	GError *error;
+	GVariant *value;
+	gchar *power_good_in_name;
+	GVariantIter *power_up_outs_iter;
+	GVariantIter *reset_outs_iter;
+	gchar *power_up_out_name;
+	gchar *reset_out_name;
+	gboolean power_up_polarity;
+	gboolean reset_out_polarity;
+	int i;
+
+	proxy = g_dbus_proxy_new_sync(connection,
+			G_DBUS_PROXY_FLAGS_NONE,
+			NULL,							/* GDBusInterfaceInfo */
+			"org.openbmc.managers.System",	/* name */
+			"/org/openbmc/managers/System",	/* object path */
+			"org.openbmc.managers.System",	/* interface */
+			NULL,							/* GCancellable */
+			&error);
+	if(error != NULL) {
+		fprintf(stderr, "Unable to create proxy: %s\n", error->message);
+		g_error_free(error);
+		return FALSE;
+	}
+
+	value = g_dbus_proxy_call_sync(proxy,
+			"getPowerConfiguration",
+			NULL,
+			G_DBUS_CALL_FLAGS_NONE,
+			-1,
+			NULL,
+			&error);
+	if(error != NULL) {
+		fprintf(stderr, "Power GPIO: call to getPowerConfiguration failed: %s\n",
+				error->message);
+		g_error_free(error);
+		return FALSE;
+	}
+
+	g_assert(value != NULL);
+	memset(power_gpio, 0, sizeof(*power_gpio));
+	g_variant_get(value, "(&sa(sb)a(sb))", &power_good_in_name,
+            &power_up_outs_iter, &reset_outs_iter);
+
+	g_print("Power GPIO power good input %s\n", power_good_in_name);
+	power_gpio->power_good_in.name = g_strdup(power_good_in_name);
+	power_gpio->num_power_up_outs = g_variant_iter_n_children(
+			power_up_outs_iter);
+	g_print("Power GPIO %d power_up outputs\n",
+			power_gpio->num_power_up_outs);
+	power_gpio->power_up_outs = g_malloc0_n(power_gpio->num_power_up_outs,
+			sizeof(GPIO));
+	power_gpio->power_up_pols = g_malloc0_n(power_gpio->num_power_up_outs,
+			sizeof(gboolean));
+	for(i = 0; g_variant_iter_next(power_up_outs_iter, "(&sb)",
+				&power_up_out_name, &power_up_polarity);
+			i++) {
+		g_print("Power GPIO power_up[%d] = %s active %s\n", i,
+				power_up_out_name, power_up_polarity ? "HIGH" : "LOW");
+		power_gpio->power_up_outs[i].name = g_strdup(power_up_out_name);
+		power_gpio->power_up_pols[i] = power_up_polarity;
+	}
+	power_gpio->num_reset_outs = g_variant_iter_n_children(reset_outs_iter);
+	g_print("Power GPIO %d reset outputs\n", power_gpio->num_reset_outs);
+	power_gpio->reset_outs = g_malloc0_n(power_gpio->num_reset_outs, sizeof(GPIO));
+	power_gpio->reset_pols = g_malloc0_n(power_gpio->num_reset_outs,
+			sizeof(gboolean));
+	for(i = 0; g_variant_iter_next(reset_outs_iter, "(&sb)", &reset_out_name,
+				&reset_out_polarity); i++) {
+		g_print("Power GPIO reset[%d] = %s active %s\n", i, reset_out_name,
+				reset_out_polarity ? "HIGH" : "LOW");
+		power_gpio->reset_outs[i].name = g_strdup(reset_out_name);
+		power_gpio->reset_pols[i] = reset_out_polarity;
+	}
+
+	g_variant_iter_free(power_up_outs_iter);
+	g_variant_iter_free(reset_outs_iter);
+	g_variant_unref(value);
+
+	return TRUE;
+}
+
+void free_power_gpio(PowerGpio *power_gpio) {
+	int i;
+	g_free(power_gpio->power_good_in.name);
+	for(i = 0; i < power_gpio->num_power_up_outs; i++) {
+		g_free(power_gpio->power_up_outs[i].name);
+	}
+	g_free(power_gpio->power_up_outs);
+	g_free(power_gpio->power_up_pols);
+	for(i = 0; i < power_gpio->num_reset_outs; i++) {
+		g_free(power_gpio->reset_outs[i].name);
+	}
+	g_free(power_gpio->reset_outs);
+	g_free(power_gpio->reset_pols);
+}
diff --git a/libopenbmc_intf/power_gpio.h b/libopenbmc_intf/power_gpio.h
new file mode 100644
index 0000000..f36a722
--- /dev/null
+++ b/libopenbmc_intf/power_gpio.h
@@ -0,0 +1,45 @@
+/**
+ * Copyright © 2016 Google Inc.
+ * Copyright © 2016 IBM Corporation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __POWER_GPIO_H__
+#define __POWER_GPIO_H__
+
+#include <stddef.h>
+#include <glib.h>
+#include "gpio.h"
+
+typedef struct PowerGpio {
+	/* Active high pin that is asserted following successful host power up. */
+	GPIO power_good_in;
+	/* Selectable polarity pins enabling host power rails. */
+	size_t num_power_up_outs;
+	GPIO *power_up_outs;
+	/* TRUE for active high */
+	gboolean *power_up_pols;
+	/* Selectable polarity pins holding system complexes in reset. */
+	size_t num_reset_outs;
+	GPIO *reset_outs;
+	/* TRUE for active high */
+	gboolean *reset_pols;
+} PowerGpio;
+
+/* Read system configuration for power GPIOs. */
+gboolean read_power_gpio(GDBusConnection *connection, PowerGpio *power_gpio);
+/* Frees internal buffers. Does not free parameter. Does not close GPIOs. */
+void free_power_gpio(PowerGpio *power_gpio);
+
+#endif