Add support for automatic USB2/3 dual power switch

When compatible USB3 hub connected to USB3 upstream port,
it is detected as 2 independent virtual hubs: USB2 and USB3,
and USB devices will be connected to USB2 or USB3 virtual hub
depending on their capabilities and connection speed.

To control power for physical USB3 hubs, we must turn off/on power
on both USB2 and USB3 virtual hubs for power off/on changes to take effect.

Included fixes:

* Enumerate all USB hubs, but mark ones we will work on with actionable flag.
  Because of this, increased max size of hubs array to 128 (maybe need even more?).
* Moved all code that was getting hub info into get_hub_info().
* Display "power" status as first status flag if port is powered.
  (uhubctl is about USB port power, and we should display power as first flag).
* Display "off" status for USB3 port when it is off (was "5gbps SS.Disabled").
  This makes both USB2 and USB3 status to display "off" consistently.
* Added expert option --exact which disables USB3 duality handling.
* Added small wait (150ms) after turning off USB3 port.
  It seems that USB3 reacts slowly to power off command.
  Perhaps we need to implement more deterministic approach for this,
  e.g. keep querying new power state few times until it has finally changed.
  Oddly enough, power on is always instant and does not need waiting.

This fixes issue #72.

1 files changed, 168 insertions, 93 deletions

diff --git a/uhubctl.c b/uhubctl.c
index dd191fd..96ffc3e 100644
--- a/uhubctl.c
+++ b/uhubctl.c
@@ -123,14 +123,16 @@ struct usb_port_status {
 #define USB_PORT_STAT_INDICATOR         0x1000
 /* bits 13 to 15 are reserved */
 
+
+#define USB_SS_BCD                      0x0300
 /*
  * Additions to wPortStatus bit field from USB 3.0
  * See USB 3.0 spec Table 10-10
  */
-#define USB_PORT_STAT_LINK_STATE	0x01e0
-#define USB_SS_PORT_STAT_POWER		0x0200
-#define USB_SS_PORT_STAT_SPEED		0x1c00
-#define USB_PORT_STAT_SPEED_5GBPS	0x0000
+#define USB_PORT_STAT_LINK_STATE        0x01e0
+#define USB_SS_PORT_STAT_POWER          0x0200
+#define USB_SS_PORT_STAT_SPEED          0x1c00
+#define USB_PORT_STAT_SPEED_5GBPS       0x0000
 /* Valid only if port is enabled */
 /* Bits that are the same from USB 2.0 */
 #define USB_SS_PORT_STAT_MASK (USB_PORT_STAT_CONNECTION  | \
@@ -183,25 +185,28 @@ struct hub_info {
     int bcd_usb;
     int nports;
     int ppps;
+    int actionable; /* true if this hub is subject to action */
     char vendor[16];
     char location[32];
     char description[256];
 };
 
-/* Array of USB hubs we are going to operate on */
-#define MAX_HUBS 64
+/* Array of all enumerated USB hubs */
+#define MAX_HUBS 128
 static struct hub_info hubs[MAX_HUBS];
 static int hub_count = 0;
+static int hub_phys_count = 0;
 
 /* default options */
 static char opt_vendor[16]   = "";
-static char opt_location[16] = "";     /* Hub location a-b.c.d */
+static char opt_location[32] = "";     /* Hub location a-b.c.d */
 static int opt_ports  = ALL_HUB_PORTS; /* Bitmask of ports to operate on */
 static int opt_action = POWER_KEEP;
 static int opt_delay  = 2;
 static int opt_repeat = 1;
 static int opt_wait   = 20; /* wait before repeating in ms */
-static int opt_reset  = 0; /* reset hub after operation(s) */
+static int opt_exact  = 0;  /* exact location match - disable USB3 duality handling */
+static int opt_reset  = 0;  /* reset hub after operation(s) */
 
 static const struct option long_options[] = {
     { "loc",      required_argument, NULL, 'l' },
@@ -211,6 +216,7 @@ static const struct option long_options[] = {
     { "delay",    required_argument, NULL, 'd' },
     { "repeat",   required_argument, NULL, 'r' },
     { "wait",     required_argument, NULL, 'w' },
+    { "exact",    no_argument,       NULL, 'e' },
     { "reset",    no_argument,       NULL, 'R' },
     { "version",  no_argument,       NULL, 'v' },
     { "help",     no_argument,       NULL, 'h' },
@@ -232,6 +238,7 @@ int print_usage()
         "--vendor,   -n - limit hub by vendor id [%s] (partial ok).\n"
         "--delay,    -d - delay for cycle action [%d sec].\n"
         "--repeat,   -r - repeat power off count [%d] (some devices need it to turn off).\n"
+        "--exact,    -e - exact location (no USB3 duality handling).\n"
         "--reset,    -R - reset hub after each power-on action, causing all devices to reassociate.\n"
         "--wait,     -w - wait before repeat power off [%d ms].\n"
         "--version,  -v - print program version.\n"
@@ -282,8 +289,8 @@ int get_hub_info(struct libusb_device *dev, struct hub_info *info)
     if (desc.bDeviceClass != LIBUSB_CLASS_HUB)
         return LIBUSB_ERROR_INVALID_PARAM;
     int bcd_usb = libusb_le16_to_cpu(desc.bcdUSB);
-    int desc_type = (bcd_usb >= 0x300) ? LIBUSB_DT_SUPERSPEED_HUB
-                                       : LIBUSB_DT_HUB;
+    int desc_type = bcd_usb >= USB_SS_BCD ? LIBUSB_DT_SUPERSPEED_HUB
+                                          : LIBUSB_DT_HUB;
     rc = libusb_open(dev, &devh);
     if (rc == 0) {
         len = libusb_control_transfer(devh,
@@ -297,10 +304,37 @@ int get_hub_info(struct libusb_device *dev, struct hub_info *info)
         );
 
         if (len >= minlen) {
+            unsigned char port_numbers[MAX_HUB_CHAIN] = {0};
             info->dev     = dev;
             info->bcd_usb = bcd_usb;
             info->nports  = uhd->bNbrPorts;
-            info->ppps    = 0;
+            snprintf(
+                info->vendor, sizeof(info->vendor),
+                "%04x:%04x",
+                libusb_le16_to_cpu(desc.idVendor),
+                libusb_le16_to_cpu(desc.idProduct)
+            );
+
+            /* Convert bus and ports array into USB location string */
+            int bus = libusb_get_bus_number(dev);
+            snprintf(info->location, sizeof(info->location), "%d", bus);
+#if defined(LIBUSB_API_VERSION) && (LIBUSB_API_VERSION >= 0x01000102)
+            /*
+             * libusb_get_port_path is deprecated since libusb v1.0.16,
+             * therefore use libusb_get_port_numbers when supported
+             */
+            int pcount = libusb_get_port_numbers(dev, port_numbers, MAX_HUB_CHAIN);
+#else
+            int pcount = libusb_get_port_path(NULL, dev, port_numbers, MAX_HUB_CHAIN);
+#endif
+            int k;
+            for (k=0; k<pcount; k++) {
+                char s[8];
+                snprintf(s, sizeof(s), "%s%d", k==0 ? "-" : ".", port_numbers[k]);
+                strcat(info->location, s);
+            }
+
+            info->ppps = 0;
             /* Logical Power Switching Mode */
             int lpsm = uhd->wHubCharacteristics[0] & HUB_CHAR_LPSM;
             /* Over-Current Protection Mode */
@@ -425,7 +459,7 @@ static int get_device_description(struct libusb_device * dev, char* description,
  * if portmask is 0, show all ports
  */
 
-static int hub_port_status(struct hub_info * hub, int portmask)
+static int print_port_status(struct hub_info * hub, int portmask)
 {
     int port_status;
     struct libusb_device_handle * devh = NULL;
@@ -460,41 +494,48 @@ static int hub_port_status(struct hub_info * hub, int portmask)
                 }
             }
 
-            if (hub->bcd_usb < 0x300) {
-                if (port_status & USB_PORT_STAT_INDICATOR)      printf(" indicator");
-                if (port_status & USB_PORT_STAT_TEST)           printf(" test");
-                if (port_status & USB_PORT_STAT_HIGH_SPEED)     printf(" highspeed");
-                if (port_status & USB_PORT_STAT_LOW_SPEED)      printf(" lowspeed");
-                if (port_status & USB_PORT_STAT_POWER)          printf(" power");
-                if (port_status & USB_PORT_STAT_SUSPEND)        printf(" suspend");
+            if (hub->bcd_usb < USB_SS_BCD) {
+                if (port_status == 0) {
+                    printf(" off");
+                } else {
+                    if (port_status & USB_PORT_STAT_POWER)        printf(" power");
+                    if (port_status & USB_PORT_STAT_INDICATOR)    printf(" indicator");
+                    if (port_status & USB_PORT_STAT_TEST)         printf(" test");
+                    if (port_status & USB_PORT_STAT_HIGH_SPEED)   printf(" highspeed");
+                    if (port_status & USB_PORT_STAT_LOW_SPEED)    printf(" lowspeed");
+                    if (port_status & USB_PORT_STAT_SUSPEND)      printf(" suspend");
+                }
             } else {
-                int link_state = port_status & USB_PORT_STAT_LINK_STATE;
-                if ((port_status & USB_SS_PORT_STAT_SPEED)
-                     == USB_PORT_STAT_SPEED_5GBPS)
-                {
-                    printf(" 5gbps");
+                if (port_status == USB_SS_PORT_LS_SS_DISABLED) {
+                    printf(" off");
+                } else {
+                    int link_state = port_status & USB_PORT_STAT_LINK_STATE;
+                    if (port_status & USB_SS_PORT_STAT_POWER)     printf(" power");
+                    if ((port_status & USB_SS_PORT_STAT_SPEED)
+                         == USB_PORT_STAT_SPEED_5GBPS)
+                    {
+                        printf(" 5gbps");
+                    }
+                    if (link_state == USB_SS_PORT_LS_U0)          printf(" U0");
+                    if (link_state == USB_SS_PORT_LS_U1)          printf(" U1");
+                    if (link_state == USB_SS_PORT_LS_U2)          printf(" U2");
+                    if (link_state == USB_SS_PORT_LS_U3)          printf(" U3");
+                    if (link_state == USB_SS_PORT_LS_SS_DISABLED) printf(" SS.Disabled");
+                    if (link_state == USB_SS_PORT_LS_RX_DETECT)   printf(" Rx.Detect");
+                    if (link_state == USB_SS_PORT_LS_SS_INACTIVE) printf(" SS.Inactive");
+                    if (link_state == USB_SS_PORT_LS_POLLING)     printf(" Polling");
+                    if (link_state == USB_SS_PORT_LS_RECOVERY)    printf(" Recovery");
+                    if (link_state == USB_SS_PORT_LS_HOT_RESET)   printf(" HotReset");
+                    if (link_state == USB_SS_PORT_LS_COMP_MOD)    printf(" Compliance");
+                    if (link_state == USB_SS_PORT_LS_LOOPBACK)    printf(" Loopback");
                 }
-                if (port_status & USB_SS_PORT_STAT_POWER)       printf(" power");
-                if (link_state == USB_SS_PORT_LS_U0)            printf(" U0");
-                if (link_state == USB_SS_PORT_LS_U1)            printf(" U1");
-                if (link_state == USB_SS_PORT_LS_U2)            printf(" U2");
-                if (link_state == USB_SS_PORT_LS_U3)            printf(" U3");
-                if (link_state == USB_SS_PORT_LS_SS_DISABLED)   printf(" SS.Disabled");
-                if (link_state == USB_SS_PORT_LS_RX_DETECT)     printf(" Rx.Detect");
-                if (link_state == USB_SS_PORT_LS_SS_INACTIVE)   printf(" SS.Inactive");
-                if (link_state == USB_SS_PORT_LS_POLLING)       printf(" Polling");
-                if (link_state == USB_SS_PORT_LS_RECOVERY)      printf(" Recovery");
-                if (link_state == USB_SS_PORT_LS_HOT_RESET)     printf(" HotReset");
-                if (link_state == USB_SS_PORT_LS_COMP_MOD)      printf(" Compliance");
-                if (link_state == USB_SS_PORT_LS_LOOPBACK)      printf(" Loopback");
             }
-            if (port_status & USB_PORT_STAT_RESET)          printf(" reset");
-            if (port_status & USB_PORT_STAT_OVERCURRENT)    printf(" oc");
-            if (port_status & USB_PORT_STAT_ENABLE)         printf(" enable");
-            if (port_status & USB_PORT_STAT_CONNECTION)     printf(" connect");
-            if (port_status == 0)                           printf(" off");
+            if (port_status & USB_PORT_STAT_RESET)       printf(" reset");
+            if (port_status & USB_PORT_STAT_OVERCURRENT) printf(" oc");
+            if (port_status & USB_PORT_STAT_ENABLE)      printf(" enable");
+            if (port_status & USB_PORT_STAT_CONNECTION)  printf(" connect");
 
-            if (port_status & USB_PORT_STAT_CONNECTION)     printf(" [%s]", description);
+            if (port_status & USB_PORT_STAT_CONNECTION)  printf(" [%s]", description);
 
             printf("\n");
         }
@@ -505,18 +546,21 @@ static int hub_port_status(struct hub_info * hub, int portmask)
 
 
 /*
- *  Find all smart hubs that we are going to work on and fill hubs[] array.
- *  This applies possible constraints like location or vendor.
- *  Returns count of found hubs or negative error code.
+ *  Find all USB hubs and fill hubs[] array.
+ *  Set actionable to 1 on all hubs that we are going to operate on
+ *  (this applies possible constraints like location or vendor).
+ *  Returns count of found actionable physical hubs
+ *  (USB3 hubs are counted once despite having USB2 dual partner).
+ *  In case of error returns negative error code.
  */
 
 static int usb_find_hubs()
 {
     struct libusb_device *dev;
-    unsigned char port_numbers[MAX_HUB_CHAIN] = {0};
     int perm_ok = 1;
     int rc = 0;
     int i = 0;
+    int j = 0;
     while ((dev = usb_devs[i++]) != NULL) {
         struct libusb_device_descriptor desc;
         rc = libusb_get_device_descriptor(dev, &desc);
@@ -529,55 +573,78 @@ static int usb_find_hubs()
         if (rc) {
             perm_ok = 0; /* USB permission issue? */
         }
+        get_device_description(dev, info.description, sizeof(info.description));
         if (info.ppps) { /* PPPS is supported */
             if (hub_count < MAX_HUBS) {
-                hubs[hub_count].dev     = dev;
-                hubs[hub_count].nports  = info.nports;
-                hubs[hub_count].bcd_usb = info.bcd_usb;
-                hubs[hub_count].ppps    = info.ppps;
-
-                snprintf(
-                    hubs[hub_count].vendor, sizeof(hubs[hub_count].vendor),
-                    "%04x:%04x",
-                    libusb_le16_to_cpu(desc.idVendor),
-                    libusb_le16_to_cpu(desc.idProduct)
-                );
-
-                get_device_description(dev, hubs[hub_count].description, sizeof(hubs[hub_count].description));
-
-                /* Convert bus and ports array into USB location string */
-                int bus = libusb_get_bus_number(dev);
-                snprintf(hubs[hub_count].location, sizeof(hubs[hub_count].location), "%d", bus);
-#if defined(LIBUSB_API_VERSION) && (LIBUSB_API_VERSION >= 0x01000102)
-                /*
-                 * libusb_get_port_path is deprecated since libusb v1.0.16,
-                 * therefore use libusb_get_port_numbers when supported
-                 */
-                int pcount = libusb_get_port_numbers(dev, port_numbers, MAX_HUB_CHAIN);
-#else
-                int pcount = libusb_get_port_path(NULL, dev, port_numbers, MAX_HUB_CHAIN);
-#endif
-                int k;
-                for (k=0; k<pcount; k++) {
-                    char s[8];
-                    snprintf(s, sizeof(s), "%s%d", k==0 ? "-" : ".", port_numbers[k]);
-                    strcat(hubs[hub_count].location, s);
+                info.actionable = 1;
+                if (strlen(opt_location)>0) {
+                    if (strcasecmp(opt_location, info.location)) {
+                       info.actionable = 0;
+                    }
                 }
-
-                /* apply location and other filters: */
-                if (strlen(opt_location)>0 && strcasecmp(opt_location, hubs[hub_count].location))
-                    continue;
-                if (strlen(opt_vendor)>0   && strncasecmp(opt_vendor,  hubs[hub_count].vendor, strlen(opt_vendor)))
-                    continue;
-
+                if (strlen(opt_vendor)>0) {
+                    if (strncasecmp(opt_vendor, info.vendor, strlen(opt_vendor))) {
+                        info.actionable = 0;
+                    }
+                }
+                memcpy(&hubs[hub_count], &info, sizeof(info));
                 hub_count++;
             }
         }
     }
-    if (perm_ok == 0 && hub_count == 0) {
+    hub_phys_count = 0;
+    for (i=0; i<hub_count; i++) {
+        /* Check only actionable USB3 hubs: */
+        if (!hubs[i].actionable)
+            continue;
+        if (hubs[i].bcd_usb < USB_SS_BCD || opt_exact) {
+            hub_phys_count++;
+        }
+        if (opt_exact)
+            continue;
+        int match = -1;
+        for (j=0; j<hub_count; j++) {
+            if (i==j)
+                continue;
+
+            /* Find hub which is USB2/3 dual to the hub above.
+             * This is quite reliable and predictable on Linux
+             * but not on Mac, where we may match wrong hub :(
+             * It will work reliably on Mac if there is
+             * only one compatible USB3 hub is connected.
+             * TODO: discover better way to find dual hub.
+             */
+
+            /* Hub and its dual must be different types: one USB2, another USB3: */
+            if ((hubs[i].bcd_usb < USB_SS_BCD) ==
+                (hubs[j].bcd_usb < USB_SS_BCD))
+                continue;
+
+            /* But they must have the same vendor: */
+            if (strncasecmp(hubs[i].vendor, hubs[j].vendor, 4))
+                continue;
+
+            /* Provisionally we choose this one as dual: */
+            if (match < 0 && !hubs[j].actionable)
+                match = j;
+
+            /* But if there is exact port path match,
+             * we prefer it (true for Linux but not Mac):
+             */
+            char *p1 = strchr(hubs[i].location, '-');
+            char *p2 = strchr(hubs[j].location, '-');
+            if (p1 && p2 && strcasecmp(p1, p2)==0) {
+                match = j;
+                break;
+            }
+        }
+        if (match >= 0)
+            hubs[match].actionable = 1;
+    }
+    if (perm_ok == 0 && hub_phys_count == 0) {
         return LIBUSB_ERROR_ACCESS;
     }
-    return hub_count;
+    return hub_phys_count;
 }
 
 
@@ -588,7 +655,7 @@ int main(int argc, char *argv[])
     int option_index = 0;
 
     for (;;) {
-        c = getopt_long(argc, argv, "l:n:a:p:d:r:w:hvR",
+        c = getopt_long(argc, argv, "l:n:a:p:d:r:w:hveR",
             long_options, &option_index);
         if (c == -1)
             break;  /* no more options left */
@@ -642,6 +709,9 @@ int main(int argc, char *argv[])
         case 'r':
             opt_repeat = atoi(optarg);
             break;
+        case 'e':
+            opt_exact = 1;
+            break;
         case 'R':
             opt_reset = 1;
             break;
@@ -713,7 +783,7 @@ int main(int argc, char *argv[])
         goto cleanup;
     }
 
-    if (hub_count > 1 && opt_action >= 0) {
+    if (hub_phys_count > 1 && opt_action >= 0) {
         fprintf(stderr,
             "Error: changing port state for multiple hubs at once is not supported.\n"
             "Use -l to limit operation to one hub!\n"
@@ -722,10 +792,12 @@ int main(int argc, char *argv[])
     }
     int i;
     for (i=0; i<hub_count; i++) {
+        if (hubs[i].actionable == 0)
+            continue;
         printf("Current status for hub %s [%s]\n",
             hubs[i].location, hubs[i].description
         );
-        hub_port_status(&hubs[i], opt_ports);
+        print_port_status(&hubs[i], opt_ports);
         if (opt_action == POWER_KEEP) { /* no action, show status */
             continue;
         }
@@ -746,8 +818,8 @@ int main(int argc, char *argv[])
                 for (port=1; port <= hubs[i].nports; port++) {
                     if ((1 << (port-1)) & ports) {
                         int port_status = get_port_status(devh, port);
-                        int power_mask = (hubs[i].bcd_usb < 0x300) ? USB_PORT_STAT_POWER
-                                                                   : USB_SS_PORT_STAT_POWER;
+                        int power_mask = hubs[i].bcd_usb < USB_SS_BCD ? USB_PORT_STAT_POWER
+                                                                          : USB_SS_PORT_STAT_POWER;
                         if (k == 0 && !(port_status & power_mask))
                             continue;
                         if (k == 1 && (port_status & power_mask))
@@ -774,13 +846,16 @@ int main(int argc, char *argv[])
                 }
                 if (k==0 && opt_action == POWER_CYCLE)
                     sleep_ms(opt_delay * 1000);
+                /* USB3 hubs need extra delay to actually turn off: */
+                if (k==0 && hubs[i].bcd_usb >= USB_SS_BCD)
+                    sleep_ms(150);
                 printf("Sent power %s request\n",
                     request == LIBUSB_REQUEST_CLEAR_FEATURE ? "off" : "on"
                 );
                 printf("New status for hub %s [%s]\n",
                     hubs[i].location, hubs[i].description
                 );
-                hub_port_status(&hubs[i], opt_ports);
+                print_port_status(&hubs[i], opt_ports);
 
                 if (k == 1 && opt_reset == 1) {
                     printf("Resetting hub...\n");