src: Add h2w detection code from pulseaudio-packaging

This applies changes from pulseaudio-packaging for detecting
headset & headphones via the h2w virtual switch file and udev.

Compared to pulseaudio-packaging this now forces udev as a requirement
rather than providing a compile-time switch.

debian/control

@@ -12,7 +12,8 @@ Build-Depends: android-headers (>= 23),
                libltdl-dev,
                libpulse-dev,
                pulseaudio-dev,
-               libexpat1-dev
+               libexpat1-dev,
+               libudev-dev
 Maintainer: Marius Gripsgard <marius@ubports.com>
 Standards-Version: 4.3.0
 Homepage: https://github.com/mer-hybris/pulseaudio-modules-droid

src/droid/Makefile.am

@@ -41,7 +41,7 @@ module_droid_source_la_LDFLAGS = -module -avoid-version -Wl,-z,noexecstack -lhyb
 module_droid_source_la_LIBADD = -lm libdroid-source.la $(AM_LIBADD)
 module_droid_source_la_CFLAGS = $(AM_CFLAGS)
 
-module_droid_card_la_SOURCES = module-droid-card.c
-module_droid_card_la_LDFLAGS = -module -avoid-version -Wl,-z,noexecstack -lhybris-common
+module_droid_card_la_SOURCES = module-droid-card.c droid-extcon.c
+module_droid_card_la_LDFLAGS = -module -avoid-version -Wl,-z,noexecstack -lhybris-common -ludev
 module_droid_card_la_LIBADD = -lm libdroid-sink.la libdroid-source.la $(top_builddir)/src/common/libdroid-util.la $(AM_LIBADD)
 module_droid_card_la_CFLAGS = $(AM_CFLAGS)

src/droid/droid-extcon.c

@@ -0,0 +1,269 @@
+/***
+  This file is part of PulseAudio.
+
+  Copyright (C) 2013 Canonical Ltd.
+  Contact: David Henningsson
+           Ricardo Salveti de Araujo <ricardo.salveti@canonical.com>
+
+  PulseAudio is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License as published
+  by the Free Software Foundation; either version 2.1 of the License,
+  or (at your option) any later version.
+
+  PulseAudio is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with PulseAudio; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <pulsecore/core-util.h>
+#include <pulsecore/device-port.h>
+#include <pulsecore/i18n.h>
+#include <libudev.h>
+
+#include "droid-extcon.h"
+
+/* For android */
+#define EXTCON_NAME "switch"
+
+/* TODO: Backport stuff to 4.0, remove before upstreaming */
+#ifndef PA_PORT_AVAILABLE_YES
+#define PA_PORT_AVAILABLE_YES PA_AVAILABLE_YES
+#define PA_PORT_AVAILABLE_NO PA_AVAILABLE_NO
+#define PA_PORT_AVAILABLE_UNKNOWN PA_AVAILABLE_UNKNOWN
+#define pa_port_available_t pa_available_t
+#endif
+
+static pa_port_available_t hponly_avail(int state)
+{
+    return (state & 2) ? PA_PORT_AVAILABLE_YES : PA_PORT_AVAILABLE_NO;
+}
+
+static pa_port_available_t hsmic_avail(int state)
+{
+    return (state & 1) ? PA_PORT_AVAILABLE_YES : PA_PORT_AVAILABLE_NO;
+}
+
+struct droid_switch {
+    char *name;
+    uint32_t current_value;
+};
+
+static void droid_switch_free(struct droid_switch *as) {
+    if (!as)
+        return;
+    pa_xfree(as->name);
+    pa_xfree(as);
+}
+
+static struct droid_switch *droid_switch_new(const char *name) {
+
+    struct droid_switch *as = NULL;
+    char *filename = pa_sprintf_malloc("/sys/class/%s/%s/state", EXTCON_NAME, name);
+    char *state = pa_read_line_from_file(filename);
+
+    if (state == NULL) {
+        pa_log_debug("Cannot open '%s'. Skipping.", filename);
+        pa_xfree(filename);
+        return NULL;
+    }
+    pa_xfree(filename);
+
+    as = pa_xnew0(struct droid_switch, 1);
+    as->name = pa_xstrdup(name);
+
+    if (pa_atou(state, &as->current_value) < 0) {
+        pa_log_warn("Switch '%s' has invalid value '%s'", name, state);
+        pa_xfree(state);
+        droid_switch_free(as);
+        return NULL;
+    }
+    pa_log_debug("Switch '%s' opened with value '%s'", name, state);
+
+    return as;
+}
+
+struct udev_data {
+    struct udev *udev;
+    struct udev_monitor *monitor;
+    pa_io_event *event;
+};
+
+struct pa_droid_extcon {
+    pa_card *card;
+    struct droid_switch *h2w;
+    struct udev_data udev;
+};
+
+static struct droid_switch *find_matching_switch(pa_droid_extcon *u,
+                                                   const char *devpath) {
+
+    if (pa_streq(devpath, "/devices/virtual/" EXTCON_NAME "/h2w"))
+        return u->h2w;  /* To be extended if we ever support more switches */
+    return NULL;
+}
+
+static void notify_ports(pa_droid_extcon *u, struct droid_switch *as) {
+
+    pa_device_port *p;
+    void *state;
+
+    pa_assert(as == u->h2w); /* To be extended if we ever support more switches */
+
+    pa_log_debug("Value of switch %s is now %d.", as->name, as->current_value);
+
+    PA_HASHMAP_FOREACH(p, u->card->ports, state) {
+        if (p->direction == PA_DIRECTION_OUTPUT) {
+            if (!strcmp(p->name, "output-wired_headset"))
+                pa_device_port_set_available(p, hsmic_avail(as->current_value));
+            if (!strcmp(p->name, "output-wired_headphone"))
+                pa_device_port_set_available(p, hponly_avail(as->current_value));
+        }
+        if (p->direction == PA_DIRECTION_INPUT) {
+            if (!strcmp(p->name, "input-wired_headset"))
+                pa_device_port_set_available(p, hsmic_avail(as->current_value));
+        }
+    }
+}
+
+static void udev_cb(pa_mainloop_api *a, pa_io_event *e, int fd,
+                    pa_io_event_flags_t events, void *userdata) {
+
+    pa_droid_extcon *u = userdata;
+    struct udev_device *d = udev_monitor_receive_device(u->udev.monitor);
+    struct udev_list_entry *entry;
+    struct droid_switch *as;
+    const char *devpath, *state;
+
+    if (!d) {
+        pa_log("udev_monitor_receive_device failed.");
+        pa_assert(a);
+        a->io_free(u->udev.event);
+        u->udev.event = NULL;
+        return;
+    }
+
+    devpath = udev_device_get_devpath(d);
+    if (!devpath) {
+        pa_log("udev_device_get_devpath failed.");
+        goto out;
+    }
+    pa_log_debug("Got uevent with devpath=%s", devpath);
+
+    as = find_matching_switch(u, devpath);
+    if (!as)
+        goto out;
+
+    entry = udev_list_entry_get_by_name(
+            udev_device_get_properties_list_entry(d), "SWITCH_STATE");
+    if (!entry) {
+        pa_log("udev_list_entry_get_by_name failed to find 'SWITCH_STATE' entry.");
+        goto out;
+    }
+
+    state = udev_list_entry_get_value(entry);
+    if (!state) {
+        pa_log("udev_list_entry_get_by_name failed.");
+        goto out;
+    }
+
+    if (pa_atou(state, &as->current_value) < 0) {
+        pa_log_warn("Switch '%s' has invalid value '%s'", as->name, state);
+        goto out;
+    }
+
+    notify_ports(u, as);
+
+out:
+    udev_device_unref(d);
+}
+
+static bool init_udev(pa_droid_extcon *u, pa_core *core) {
+
+    int fd;
+
+    u->udev.udev = udev_new();
+    if (!u->udev.udev) {
+        pa_log("udev_new failed.");
+        return false;
+    }
+
+    u->udev.monitor = udev_monitor_new_from_netlink(u->udev.udev, "udev");
+    if (!u->udev.monitor) {
+        pa_log("udev_monitor_new_from_netlink failed.");
+        return false;
+    }
+
+    if (udev_monitor_filter_add_match_subsystem_devtype(u->udev.monitor, EXTCON_NAME, NULL) < 0) {
+        pa_log("udev_monitor_filter_add_match_subsystem_devtype failed.");
+        return false;
+    }
+
+    if (udev_monitor_enable_receiving(u->udev.monitor) < 0) {
+        pa_log("udev_monitor_enable_receiving failed.");
+        return false;
+    }
+
+    fd = udev_monitor_get_fd(u->udev.monitor);
+    if (fd < 0) {
+        pa_log("udev_monitor_get_fd failed");
+        return false;
+    }
+
+    pa_assert_se(u->udev.event = core->mainloop->io_new(core->mainloop, fd,
+                 PA_IO_EVENT_INPUT, udev_cb, u));
+
+    return true;
+}
+
+pa_droid_extcon *pa_droid_extcon_new(pa_core *core, pa_card *card) {
+
+    pa_droid_extcon *u = pa_xnew0(pa_droid_extcon, 1);
+
+    pa_assert(core);
+    pa_assert(card);
+
+    u->card = card;
+    u->h2w = droid_switch_new("h2w");
+    if (!u->h2w)
+        goto fail;
+
+    if (!init_udev(u, core))
+        goto fail;
+
+    notify_ports(u, u->h2w);
+
+    return u;
+
+fail:
+    pa_droid_extcon_free(u);
+    return NULL;
+}
+
+void pa_droid_extcon_free(pa_droid_extcon *u) {
+
+    pa_assert(u);
+
+    if (u->udev.event)
+        u->card->core->mainloop->io_free(u->udev.event);
+
+    if (u->udev.monitor)
+        udev_monitor_unref(u->udev.monitor);
+
+    if (u->udev.udev)
+        udev_unref(u->udev.udev);
+
+    if (u->h2w)
+        droid_switch_free(u->h2w);
+
+    pa_xfree(u);
+}

src/droid/droid-extcon.h

@@ -0,0 +1,32 @@
+#ifndef foodroidextconhfoo
+#define foodroidextconhfoo
+
+/***
+  This file is part of PulseAudio.
+
+  Copyright (C) 2013 Canonical Ltd.
+  Contact: David Henningsson
+
+  PulseAudio is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License as published
+  by the Free Software Foundation; either version 2.1 of the License,
+  or (at your option) any later version.
+
+  PulseAudio is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with PulseAudio; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+typedef struct pa_droid_extcon pa_droid_extcon;
+
+pa_droid_extcon *pa_droid_extcon_new(pa_core *, pa_card *);
+
+void pa_droid_extcon_free(pa_droid_extcon *);
+
+#endif

src/droid/module-droid-card.c

@@ -63,6 +63,7 @@
 #include <droid/sllist.h>
 #include "droid-sink.h"
 #include "droid-source.h"
+#include "droid-extcon.h"
 
 #include "module-droid-card-symdef.h"
 
@@ -160,6 +161,8 @@ struct userdata {
 
     pa_card_profile *real_profile;
 
+    pa_droid_extcon *extcon;
+
     pa_modargs *modargs;
     pa_card *card;
 };
@@ -867,6 +870,8 @@ int pa__init(pa_module *m) {
 
     pa_card_choose_initial_profile(u->card);
     init_profile(u);
+    u->extcon = pa_droid_extcon_new(m->core, u->card);
+
     pa_card_put(u->card);
 
     return 0;
@@ -895,6 +900,8 @@ void pa__done(pa_module *m) {
         if (u->card && u->card->sources)
             pa_idxset_remove_all(u->card->sources, (pa_free_cb_t) pa_droid_source_free);
 
+        if (u->extcon)
+            pa_droid_extcon_free(u->extcon);
 
         if (u->card)
             pa_card_free(u->card);