Gary Carlson <gcarlson@carlson-minot.com>

Spencer Oliver <spen@spen-soft.co.uk>

- fix jlink win32/linux/darwin startup issues
- see https://lists.berlios.de/pipermail/openocd-development/2009-July/009438.html

git-svn-id: svn://svn.berlios.de/openocd/trunk@2513 b42882b7-edfa-0310-969c-e2dbd0fdcd60

diff --git a/src/jtag/jlink.c b/src/jtag/jlink.c
index aff1a6cae7aa3dd4a511b0786e7d15ff95b96d38..d8bfb0f391162b0e9f461ba855b4e851d4789a67 100644 (file)
--- a/src/jtag/jlink.c
+++ b/src/jtag/jlink.c
@@ -835,13 +835,37 @@ static int jlink_tap_execute(void)
        return ERROR_OK;
 }
 
+static struct usb_device* find_jlink_device(void)
+{
+       struct usb_bus *busses;
+       struct usb_bus *bus;
+       struct usb_device *dev;
+
+       usb_find_busses();
+       usb_find_devices();
+
+       busses = usb_get_busses();
+
+       /* find jlink_jtag device in usb bus */
+
+       for (bus = busses; bus; bus = bus->next)
+       {
+               for (dev = bus->devices; dev; dev = dev->next)
+               {
+                       if ((dev->descriptor.idVendor == VID) && (dev->descriptor.idProduct == PID)) {
+                               return dev;
+                       }
+               }
+       }
+
+       return NULL;
+}
+
 /*****************************************************************************/
 /* JLink USB low-level functions */
 
 static jlink_jtag_t* jlink_usb_open()
 {
-       struct usb_bus *busses;
-       struct usb_bus *bus;
        struct usb_device *dev;
 
        jlink_jtag_t *result;
@@ -849,56 +873,81 @@ static jlink_jtag_t* jlink_usb_open()
        result = (jlink_jtag_t*) malloc(sizeof(jlink_jtag_t));
 
        usb_init();
-       usb_find_busses();
-       usb_find_devices();
 
-       busses = usb_get_busses();
+       if ((dev = find_jlink_device()) == NULL) {
+               free(result);
+               return NULL;
+       }
 
-       /* find jlink_jtag device in usb bus */
+       result->usb_handle = usb_open(dev);
 
-       for (bus = busses; bus; bus = bus->next)
+       if (result->usb_handle)
        {
-               for (dev = bus->devices; dev; dev = dev->next)
+       
+               /* BE ***VERY CAREFUL*** ABOUT MAKING CHANGES IN THIS AREA!!!!!!!!!!!
+                * The behavior of libusb is not completely consistent across Windows, Linux, and Mac OS X platforms.  The actions taken
+                * in the following compiler conditionals may not agree with published documentation for libusb, but were found
+                * to be necessary through trials and tribulations.  Even little tweaks can break one or more platforms, so if you do make changes
+                * test them carefully on all platforms before committing them!
+                */
+
+#if IS_WIN32 == 0
+
+               usb_reset(result->usb_handle);
+
+#if IS_DARWIN == 0
+
+               int timeout = 5;
+
+               /* reopen jlink after usb_reset
+                * on win32 this may take a second or two to re-enumerate */
+               while ((dev = find_jlink_device()) == NULL)
                {
-                       if ((dev->descriptor.idVendor == VID) && (dev->descriptor.idProduct == PID))
-                       {
-                               result->usb_handle = usb_open(dev);
-                               
-                               /*
-                                *      Some j-link dongles experience intermittent communication issues at startup to varying degrees
-                                *      depending on the host operating system.  Troubleshooting this problem all the way back to libusb
-                                *      revealed that without a usb reset, the hardware can start in an uncertain state causing a litany
-                                *      of annoying problems.  The next step was added to the original code to address this problem.
-                                */
-                               
-                               usb_reset(result->usb_handle);
-
-                               /* usb_set_configuration required under win32 */
-                               usb_set_configuration(result->usb_handle, dev->config[0].bConfigurationValue);
-                               usb_claim_interface(result->usb_handle, 0);
+                       usleep(1000);
+                       timeout--;
+                       if (!timeout) {
+                               break;
+                       }
+               }
+
+               if (dev == NULL)
+               {
+                       free(result);
+                       return NULL;
+               }
+
+               result->usb_handle = usb_open(dev);
+#endif
+
+#endif
+
+               if (result->usb_handle)
+               {
+                       /* usb_set_configuration required under win32 */
+                       usb_set_configuration(result->usb_handle, dev->config[0].bConfigurationValue);
+                       usb_claim_interface(result->usb_handle, 0);
 
 #if 0
-                               /*
-                                * This makes problems under Mac OS X. And is not needed
-                                * under Windows. Hopefully this will not break a linux build
-                                */
-                               usb_set_altinterface(result->usb_handle, 0);
+                       /*
+                        * This makes problems under Mac OS X. And is not needed
+                        * under Windows. Hopefully this will not break a linux build
+                        */
+                       usb_set_altinterface(result->usb_handle, 0);
 #endif
-                               struct usb_interface *iface = dev->config->interface;
-                               struct usb_interface_descriptor *desc = iface->altsetting;
-                               for (int i = 0; i < desc->bNumEndpoints; i++)
-                               {
-                                       uint8_t epnum = desc->endpoint[i].bEndpointAddress;
-                                       bool is_input = epnum & 0x80;
-                                       LOG_DEBUG("usb ep %s %02x", is_input ? "in" : "out", epnum);
-                                       if (is_input)
-                                               jlink_read_ep = epnum;
-                                       else
-                                               jlink_write_ep = epnum;
-                               }
-
-                               return result;
+                       struct usb_interface *iface = dev->config->interface;
+                       struct usb_interface_descriptor *desc = iface->altsetting;
+                       for (int i = 0; i < desc->bNumEndpoints; i++)
+                       {
+                               uint8_t epnum = desc->endpoint[i].bEndpointAddress;
+                               bool is_input = epnum & 0x80;
+                               LOG_DEBUG("usb ep %s %02x", is_input ? "in" : "out", epnum);
+                               if (is_input)
+                                       jlink_read_ep = epnum;
+                               else
+                                       jlink_write_ep = epnum;
                        }
+
+                       return result;
                }
        }