wifi: support adding p2p0 when starting wpa_supplicant

For TI wlan chips in p2p mode we need this omapzoom cherry-pick
to start p2p0 correctly.

http://www.omapzoom.org/?p=platform/hardware/libhardware_legacy.git;a=commit;h=ccb4c24db795059f1df365d313d80c6b269bc55e
By: Arik Nemtsov <arik@wizery.com>
On: Tue, 31 Jul 2012 21:21:20

Original commit description:
Add p2p0 using an NL80211 command when wpa_supplicant is started, and
p2p_supported is enabled.

Change-Id: Ibc0ad138513f024672642cc5764a81510aa38625
Signed-off-by: Hashcode <hashcode0f@gmail.com>

From: Barak Bercovitz <barak@wizery.com>
Date: Fri, 18 Oct 2013 12:41:32 +0300
Subject: [PATCH] wifi: remove p2p interface on supplicant stop

wifi: remove p2p interface on supplicant stop

remove p2p interface on wpa_supplicant stop
so next time it is started it won't fail when trying
to create p2p again

Change-Id: I7a4c5e9a82a013afc75548d175d5850d67fcd927

1 files changed, 246 insertions, 0 deletions

diff --git a/wifi/wifi.c b/wifi/wifi.c
index 7ee355a..cc76d21 100644
--- a/wifi/wifi.c
+++ b/wifi/wifi.c
@@ -24,6 +24,17 @@
 #include <unistd.h>
 #include <poll.h>
 
+#ifdef USES_TI_MAC80211
+#include <dirent.h>
+#include <net/if.h>
+#include <netlink/genl/genl.h>
+#include <netlink/genl/family.h>
+#include <netlink/genl/ctrl.h>
+#include <netlink/msg.h>
+#include <netlink/attr.h>
+#include <linux/nl80211.h>
+#endif
+
 #include "hardware_legacy/wifi.h"
 #include "hardware_legacy/wifi_fst.h"
 #ifdef LIBWPA_CLIENT_EXISTS
@@ -75,6 +86,13 @@ static char primary_iface[PROPERTY_VALUE_MAX];
 // TODO: use new ANDROID_SOCKET mechanism, once support for multiple
 // sockets is in
 
+#ifdef USES_TI_MAC80211
+#define P2P_INTERFACE			"p2p0"
+struct nl_sock *nl_soc;
+struct nl_cache *nl_cache;
+struct genl_family *nl80211;
+#endif
+
 #ifndef WIFI_DRIVER_MODULE_ARG
 #define WIFI_DRIVER_MODULE_ARG          ""
 #endif
@@ -443,6 +461,220 @@ int ensure_config_file_exists(const char *config_file, const char *config_file_t
     return 0;
 }
 
+#ifdef USES_TI_MAC80211
+static int init_nl()
+{
+    int err;
+
+    nl_soc = nl_socket_alloc();
+    if (!nl_soc) {
+        ALOGE("Failed to allocate netlink socket.");
+        return -ENOMEM;
+    }
+
+    if (genl_connect(nl_soc)) {
+        ALOGE("Failed to connect to generic netlink.");
+        err = -ENOLINK;
+        goto out_handle_destroy;
+    }
+
+    genl_ctrl_alloc_cache(nl_soc, &nl_cache);
+    if (!nl_cache) {
+        ALOGE("Failed to allocate generic netlink cache.");
+        err = -ENOMEM;
+        goto out_handle_destroy;
+    }
+
+    nl80211 = genl_ctrl_search_by_name(nl_cache, "nl80211");
+    if (!nl80211) {
+        ALOGE("nl80211 not found.");
+        err = -ENOENT;
+        goto out_cache_free;
+    }
+
+    return 0;
+
+out_cache_free:
+    nl_cache_free(nl_cache);
+out_handle_destroy:
+    nl_socket_free(nl_soc);
+    return err;
+}
+
+static void deinit_nl()
+{
+    genl_family_put(nl80211);
+    nl_cache_free(nl_cache);
+    nl_socket_free(nl_soc);
+}
+
+// ignore the "." and ".." entries
+static int dir_filter(const struct dirent *name)
+{
+    if (0 == strcmp("..", name->d_name) ||
+        0 == strcmp(".", name->d_name))
+            return 0;
+
+    return 1;
+}
+
+// lookup the only active phy
+int phy_lookup()
+{
+    char buf[200];
+    int fd, pos;
+    struct dirent **namelist;
+    int n, i;
+
+    n = scandir("/sys/class/ieee80211", &namelist, dir_filter,
+                (int (*)(const struct dirent**, const struct dirent**))alphasort);
+    if (n != 1) {
+        ALOGE("unexpected - found %d phys in /sys/class/ieee80211", n);
+        for (i = 0; i < n; i++)
+            free(namelist[i]);
+        free(namelist);
+        return -1;
+    }
+
+    snprintf(buf, sizeof(buf), "/sys/class/ieee80211/%s/index",
+             namelist[0]->d_name);
+    free(namelist[0]);
+    free(namelist);
+
+    fd = open(buf, O_RDONLY);
+    if (fd < 0)
+        return -1;
+    pos = read(fd, buf, sizeof(buf) - 1);
+    if (pos < 0) {
+        close(fd);
+        return -1;
+    }
+    buf[pos] = '\0';
+    close(fd);
+    return atoi(buf);
+}
+
+int nl_error_handler(struct sockaddr_nl *nla, struct nlmsgerr *err, void *arg)
+{
+    int *ret = (int *)arg;
+    *ret = err->error;
+    return NL_STOP;
+}
+
+int nl_finish_handler(struct nl_msg *msg, void *arg)
+{
+     int *ret = (int *)arg;
+     *ret = 0;
+     return NL_SKIP;
+}
+
+int nl_ack_handler(struct nl_msg *msg, void *arg)
+{
+    int *ret = (int *)arg;
+    *ret = 0;
+    return NL_STOP;
+}
+
+static int execute_nl_interface_cmd(const char *iface,
+                                    enum nl80211_iftype type,
+                                    uint8_t cmd)
+{
+    struct nl_cb *cb;
+    struct nl_msg *msg;
+    int devidx = 0;
+    int err;
+    int add_interface = (cmd == NL80211_CMD_NEW_INTERFACE);
+
+    if (add_interface) {
+        devidx = phy_lookup();
+    } else {
+        devidx = if_nametoindex(iface);
+        if (devidx == 0) {
+            ALOGE("failed to translate ifname to idx");
+            return -errno;
+        }
+    }
+
+    msg = nlmsg_alloc();
+    if (!msg) {
+        ALOGE("failed to allocate netlink message");
+        return 2;
+    }
+
+    cb = nl_cb_alloc(NL_CB_DEFAULT);
+    if (!cb) {
+        ALOGE("failed to allocate netlink callbacks");
+        err = 2;
+        goto out_free_msg;
+    }
+
+    genlmsg_put(msg, 0, 0, genl_family_get_id(nl80211), 0, 0, cmd, 0);
+
+    if (add_interface) {
+        NLA_PUT_U32(msg, NL80211_ATTR_WIPHY, devidx);
+    } else {
+        NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, devidx);
+    }
+
+    if (add_interface) {
+        NLA_PUT_STRING(msg, NL80211_ATTR_IFNAME, iface);
+        NLA_PUT_U32(msg, NL80211_ATTR_IFTYPE, type);
+    }
+
+    err = nl_send_auto_complete(nl_soc, msg);
+    if (err < 0)
+        goto out;
+
+    err = 1;
+
+    nl_cb_err(cb, NL_CB_CUSTOM, nl_error_handler, &err);
+    nl_cb_set(cb, NL_CB_FINISH, NL_CB_CUSTOM, nl_finish_handler, &err);
+    nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, nl_ack_handler, &err);
+
+    while (err > 0)
+        nl_recvmsgs(nl_soc, cb);
+out:
+    nl_cb_put(cb);
+out_free_msg:
+    nlmsg_free(msg);
+    return err;
+nla_put_failure:
+    ALOGW("building message failed");
+    return 2;
+}
+
+int add_remove_p2p_interface(int add)
+{
+    int ret;
+
+    ret = init_nl();
+    if (ret != 0)
+        return ret;
+
+    if (add) {
+        ret = execute_nl_interface_cmd(P2P_INTERFACE, NL80211_IFTYPE_STATION,
+                                       NL80211_CMD_NEW_INTERFACE);
+        if (ret != 0) {
+            ALOGE("could not add P2P interface: %d", ret);
+            goto cleanup;
+        }
+    } else {
+        ret = execute_nl_interface_cmd(P2P_INTERFACE, NL80211_IFTYPE_STATION,
+                                       NL80211_CMD_DEL_INTERFACE);
+        if (ret != 0) {
+            ALOGE("could not remove P2P interface: %d", ret);
+            goto cleanup;
+        }
+    }
+
+    ALOGD("added/removed p2p interface. add: %d", add);
+
+cleanup:
+    deinit_nl();
+    return ret;
+}
+#endif /* USES_TI_MAC80211 */
+
 int wifi_start_supplicant(int p2p_supported)
 {
     char supp_status[PROPERTY_VALUE_MAX] = {'\0'};
@@ -485,6 +717,13 @@ int wifi_start_supplicant(int p2p_supported)
         ALOGE("Wi-Fi entropy file was not created");
     }
 
+#ifdef USES_TI_MAC80211
+    if (p2p_supported && add_remove_p2p_interface(1) < 0) {
+        ALOGE("Wi-Fi - could not create p2p interface");
+        return -1;
+    }
+#endif
+
     /* Clear out any stale socket files that might be left over. */
     wpa_ctrl_cleanup();
 
@@ -549,6 +788,13 @@ int wifi_stop_supplicant(int p2p_supported)
         return 0;
     }
 
+#ifdef USES_TI_MAC80211
+    if (p2p_supported && add_remove_p2p_interface(0) < 0) {
+        ALOGE("Wi-Fi - could not remove p2p interface");
+        return -1;
+    }
+#endif
+
     property_set("ctl.stop", supplicant_name);
     sched_yield();