diff --git a/meson.build b/meson.build
index 734eaa8..9834573 100644
--- a/meson.build
+++ b/meson.build
@@ -44,6 +44,7 @@ mgr_deps = [
     dependency('glib-2.0'),
     dependency('gio-unix-2.0'),
     dependency('libgpiod'),
+    dependency('libusb-1.0'),
     dependency('mm-glib'),
 ]
 
diff --git a/src/at.c b/src/at.c
index 87c7030..c0cd92b 100644
--- a/src/at.c
+++ b/src/at.c
@@ -31,7 +31,7 @@ static int configure_serial(const char *tty)
     struct termios ttycfg;
     int fd;
 
-    fd = open(tty, O_RDWR | O_NOCTTY);
+    fd = open(tty, O_RDWR | O_NOCTTY | O_NONBLOCK);
     if (fd > 0) {
         tcgetattr(fd, &ttycfg);
         ttycfg.c_iflag &= ~(IGNBRK | BRKINT | ICRNL | INLCR | PARMRK | INPCK | ISTRIP | IXON);
@@ -143,7 +143,6 @@ static int append_at_command(struct EG25Manager *manager,
     if (!at_cmd)
         return -1;
 
-    at_cmd->retries = 0;
     at_cmd->cmd = g_strdup(cmd);
     if (subcmd)
         at_cmd->subcmd = g_strdup(subcmd);
@@ -157,22 +156,33 @@ static int append_at_command(struct EG25Manager *manager,
     return 0;
 }
 
+#define READ_BUFFER_SIZE 256
+
 static gboolean modem_response(gint fd,
                                GIOCondition event,
                                gpointer data)
 {
     struct EG25Manager *manager = data;
-    char response[256];
-    int ret;
+    char response[READ_BUFFER_SIZE*4+1];
+    char tmp[READ_BUFFER_SIZE];
+    ssize_t ret, pos = 0;
 
     /*
-     * TODO: several reads can be necessary to get the full response, we could
-     * loop until we read 0 chars with a reasonable delay between attempts
+     * Several reads can be necessary to get the full response, so we loop
+     * until we read 0 chars with a reasonable delay between attempts
      * (remember the transfer rate is 115200 here)
      */
-    ret = read(fd, response, sizeof(response));
-    if (ret > 0) {
-        response[ret] = 0;
+    do {
+        ret = read(fd, tmp, sizeof(tmp));
+        if (ret > 0) {
+            memcpy(&response[pos], tmp, ret);
+            pos += ret;
+            usleep(10000);
+        }
+    } while (ret > 0 && pos < (sizeof(response) - 1));
+
+    if (pos > 0) {
+        response[pos] = 0;
         g_strstrip(response);
         if (strlen(response) == 0)
             return TRUE;
@@ -181,7 +191,7 @@ static gboolean modem_response(gint fd,
 
         if (strcmp(response, "RDY") == 0)
             manager->modem_state = EG25_STATE_STARTED;
-        else if (strcmp(response, "ERROR") == 0)
+        else if (strstr(response, "ERROR"))
             retry_at_command(manager);
         else if (strstr(response, "OK"))
             process_at_result(manager, response);
@@ -249,7 +259,7 @@ void at_sequence_configure(struct EG25Manager *manager)
 
 void at_sequence_suspend(struct EG25Manager *manager)
 {
-    append_at_command(manager, "QGPS", NULL, NULL, "0");
+    append_at_command(manager, "QGPS", NULL, "0", NULL);
     append_at_command(manager, "QCFG", "urc/cache", "1", NULL);
     send_at_command(manager);
 }
@@ -257,7 +267,7 @@ void at_sequence_suspend(struct EG25Manager *manager)
 void at_sequence_resume(struct EG25Manager *manager)
 {
     append_at_command(manager, "QCFG", "urc/cache", "0", NULL);
-    append_at_command(manager, "QGPS", NULL, NULL, "1");
+    append_at_command(manager, "QGPS", NULL, "1", NULL);
     send_at_command(manager);
 }
 
diff --git a/src/gpio.c b/src/gpio.c
index fac7358..d22b30d 100644
--- a/src/gpio.c
+++ b/src/gpio.c
@@ -57,7 +57,7 @@ int gpio_sequence_poweron(struct EG25Manager *manager)
     sleep(1);
     gpiod_line_set_value(manager->gpio_out[GPIO_OUT_PWRKEY], 0);
 
-    g_message("Executed power-on sequence");
+    g_message("Executed power-on/off sequence");
 
     return 0;
 }
@@ -172,13 +172,16 @@ int gpio_init(struct EG25Manager *manager)
     return 0;
 }
 
-gboolean gpio_check_poweroff(struct EG25Manager *manager)
+gboolean gpio_check_poweroff(struct EG25Manager *manager, gboolean keep_down)
 {
     if (manager->gpio_in[GPIO_IN_STATUS] &&
         gpiod_line_get_value(manager->gpio_in[GPIO_IN_STATUS]) == 1) {
 
-        // Asserting RESET line to prevent modem from rebooting
-        gpiod_line_set_value(manager->gpio_out[GPIO_OUT_RESET], 1);
+        if (keep_down) {
+            // Asserting RESET line to prevent modem from rebooting
+            gpiod_line_set_value(manager->gpio_out[GPIO_OUT_RESET], 1);
+        }
+
         return TRUE;
     }
 
diff --git a/src/gpio.h b/src/gpio.h
index a31c1ce..1f1efa6 100644
--- a/src/gpio.h
+++ b/src/gpio.h
@@ -16,4 +16,4 @@ int gpio_sequence_shutdown(struct EG25Manager *state);
 int gpio_sequence_suspend(struct EG25Manager *state);
 int gpio_sequence_resume(struct EG25Manager *state);
 
-gboolean gpio_check_poweroff(struct EG25Manager *manager);
+gboolean gpio_check_poweroff(struct EG25Manager *manager, gboolean keep_down);
diff --git a/src/manager.c b/src/manager.c
index fa75741..78bf98b 100644
--- a/src/manager.c
+++ b/src/manager.c
@@ -16,6 +16,10 @@
 #include <unistd.h>
 
 #include <glib-unix.h>
+#include <libusb.h>
+
+#define EG25_USB_VID 0x2c7c
+#define EG25_USB_PID 0x0125
 
 static gboolean quit_app(struct EG25Manager *manager)
 {
@@ -32,7 +36,7 @@ static gboolean quit_app(struct EG25Manager *manager)
         gpio_sequence_shutdown(manager);
         manager->modem_state = EG25_STATE_FINISHING;
         for (i = 0; i < 30; i++) {
-            if (gpio_check_poweroff(manager))
+            if (gpio_check_poweroff(manager, TRUE))
                 break;
             sleep(1);
         }
@@ -46,9 +50,40 @@ static gboolean quit_app(struct EG25Manager *manager)
 
 static gboolean modem_start(struct EG25Manager *manager)
 {
-    g_message("Starting modem...");
-    gpio_sequence_poweron(manager);
-    manager->modem_state = EG25_STATE_POWERED;
+    ssize_t i, count;
+    gboolean should_boot = TRUE;
+    libusb_context *ctx = NULL;
+    libusb_device **devices = NULL;
+    struct libusb_device_descriptor desc;
+
+    if (manager->braveheart) {
+        // BH don't have the STATUS line connected, so check if USB device is present
+        libusb_init(&ctx);
+
+        count = libusb_get_device_list(ctx, &devices);
+        for (i = 0; i < count; i++) {
+            libusb_get_device_descriptor(devices[i], &desc);
+            if (desc.idVendor == EG25_USB_VID && desc.idProduct == EG25_USB_PID) {
+                g_message("Found corresponding USB device, modem already powered");
+                should_boot = FALSE;
+                break;
+            }
+        }
+
+        libusb_free_device_list(devices, 1);
+        libusb_exit(ctx);
+    } else if (!gpio_check_poweroff(manager, FALSE)) {
+        g_message("STATUS is low, modem already powered");
+        should_boot = FALSE;
+    }
+
+    if (should_boot) {
+        g_message("Starting modem...");
+        gpio_sequence_poweron(manager);
+        manager->modem_state = EG25_STATE_POWERED;
+    } else {
+        manager->modem_state = EG25_STATE_STARTED;
+    }
 
     return FALSE;
 }
@@ -100,14 +135,20 @@ error:
     manager->modem_state = EG25_STATE_RESETTING;
 }
 
-void modem_suspend(struct EG25Manager *manager)
+void modem_suspend_pre(struct EG25Manager *manager)
 {
+    manager->modem_state = EG25_STATE_SUSPENDING;
     gpio_sequence_suspend(manager);
+}
+
+void modem_suspend_post(struct EG25Manager *manager)
+{
     at_sequence_suspend(manager);
 }
 
 void modem_resume_pre(struct EG25Manager *manager)
 {
+    manager->modem_state = EG25_STATE_RESUMING;
     gpio_sequence_resume(manager);
 }
 
diff --git a/src/manager.h b/src/manager.h
index 714a812..be92a09 100644
--- a/src/manager.h
+++ b/src/manager.h
@@ -51,7 +51,8 @@ struct EG25Manager {
 
 void modem_configure(struct EG25Manager *data);
 void modem_reset(struct EG25Manager *data);
-void modem_suspend(struct EG25Manager *data);
+void modem_suspend_pre(struct EG25Manager *data);
+void modem_suspend_post(struct EG25Manager *data);
 void modem_resume_pre(struct EG25Manager *data);
 void modem_resume_post(struct EG25Manager *data);
 void modem_update_state(struct EG25Manager *data, MMModemState state);
diff --git a/src/mm-iface.c b/src/mm-iface.c
index f1021de..9bf9209 100644
--- a/src/mm-iface.c
+++ b/src/mm-iface.c
@@ -132,6 +132,9 @@ static void object_removed_cb(struct EG25Manager *manager, GDBusObject *object)
     path = g_dbus_object_get_object_path(object);
     g_message("ModemManager object `%s' removed", path);
 
+    if (manager->modem_state == EG25_STATE_SUSPENDING)
+        modem_suspend_post(manager);
+
     manager->mm_modem = NULL;
     if (manager->modem_usb_id) {
         g_free(manager->modem_usb_id);
diff --git a/src/suspend.c b/src/suspend.c
index 8296696..42a18f7 100644
--- a/src/suspend.c
+++ b/src/suspend.c
@@ -92,13 +92,11 @@ static void signal_cb(GDBusProxy *proxy,
 
     if (is_about_to_suspend) {
         g_message("system is about to suspend");
-        manager->modem_state = EG25_STATE_SUSPENDING;
-        modem_suspend(manager);
+        modem_suspend_pre(manager);
     } else {
         g_message("system is resuming");
         take_inhibitor(manager);
         modem_resume_pre(manager);
-        manager->modem_state = EG25_STATE_RESUMING;
         manager->suspend_source = g_timeout_add_seconds(8, G_SOURCE_FUNC(check_modem_resume), manager);
     }
 }