jtag: fix regression with dummy driver and when starting OpenOCD with target powered...

Do not fail startup if communication with target is
not possible.

OpenOCD supports launching without a target connected
or the target powered down.

The user will typically power up the target and issue
a "reset init" + load his application after OpenOCD
is started then.

Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>

diff --git a/src/jtag/core.c b/src/jtag/core.c
index 1068681964ee379a858078f434c31174cd4f1f82..6f9d92a53d1b1ec6fe69601f0ecd278add1a74a1 100644 (file)
--- a/src/jtag/core.c
+++ b/src/jtag/core.c
@@ -1445,17 +1445,19 @@ int jtag_init_inner(struct command_context *cmd_ctx)
        case ERROR_OK:
                /* complete success */
                break;
-       case ERROR_JTAG_INIT_SOFT_FAIL:
+       default:
                /* For backward compatibility reasons, try coping with
                 * configuration errors involving only ID mismatches.
                 * We might be able to talk to the devices.
+                *
+                * Also the device might be powered down during startup.
+                *
+                * After OpenOCD starts, we can try to power on the device
+                * and run a reset.
                 */
                LOG_ERROR("Trying to use configured scan chain anyway...");
                issue_setup = false;
                break;
-       default:
-               /* some hard error; already issued diagnostics */
-               return retval;
        }
 
        /* Now look at IR values.  Problems here will prevent real
@@ -1466,7 +1468,13 @@ int jtag_init_inner(struct command_context *cmd_ctx)
         */
        retval = jtag_validate_ircapture();
        if (retval != ERROR_OK)
-               return retval;
+       {
+               /* The target might be powered down. The user
+                * can power it up and reset it after firing
+                * up OpenOCD.
+                */
+               issue_setup = false;
+       }
 
        if (issue_setup)
                jtag_notify_event(JTAG_TAP_EVENT_SETUP);