jtag: simplify management of non-implemented handlers

There is just a single entry point for the jtag API .khz(),
.speed_div(), .power_dropout(), .srst_asserted().

Simplify the code by in-lining the default handler.
The overall code behaviour is not changed.
This change prevents modifying at run-time the content of
struct jtag_interface.

Inspired from change http://openocd.zylin.com/943
by Evan Hunter <ehunter@broadcom.com>

Change-Id: I09aeb76d614db57b1884ac7ee9f00c152cd77849
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/4892
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>

diff --git a/src/jtag/adapter.c b/src/jtag/adapter.c
index e11f4e9067efdc9a1e51be1d9361409e89f3312a..b1be28e5fcc4d5d29c901a45d635f48b1df2babb 100644 (file)
--- a/src/jtag/adapter.c
+++ b/src/jtag/adapter.c
@@ -66,30 +66,6 @@ static int jim_adapter_name(Jim_Interp *interp, int argc, Jim_Obj * const *argv)
        return JIM_OK;
 }
 
-static int default_khz(int khz, int *jtag_speed)
-{
-       LOG_ERROR("Translation from khz to jtag_speed not implemented");
-       return ERROR_FAIL;
-}
-
-static int default_speed_div(int speed, int *khz)
-{
-       LOG_ERROR("Translation from jtag_speed to khz not implemented");
-       return ERROR_FAIL;
-}
-
-static int default_power_dropout(int *dropout)
-{
-       *dropout = 0; /* by default we can't detect power dropout */
-       return ERROR_OK;
-}
-
-static int default_srst_asserted(int *srst_asserted)
-{
-       *srst_asserted = 0; /* by default we can't detect srst asserted */
-       return ERROR_OK;
-}
-
 COMMAND_HANDLER(interface_transport_command)
 {
        char **transports;
@@ -158,21 +134,8 @@ COMMAND_HANDLER(handle_interface_command)
                        LOG_WARNING("Adapter driver '%s' did not declare "
                                "which transports it allows; assuming "
                                "legacy JTAG-only", jtag_interface->name);
-               retval = allow_transports(CMD_CTX, jtag_interface->transports
+               return allow_transports(CMD_CTX, jtag_interface->transports
                                                ? jtag_interface->transports : jtag_only);
-                       if (ERROR_OK != retval)
-                               return retval;
-
-               if (jtag_interface->khz == NULL)
-                       jtag_interface->khz = default_khz;
-               if (jtag_interface->speed_div == NULL)
-                       jtag_interface->speed_div = default_speed_div;
-               if (jtag_interface->power_dropout == NULL)
-                       jtag_interface->power_dropout = default_power_dropout;
-               if (jtag_interface->srst_asserted == NULL)
-                       jtag_interface->srst_asserted = default_srst_asserted;
-
-               return ERROR_OK;
        }
 
        /* no valid interface was found (i.e. the configuration option,

diff --git a/src/jtag/core.c b/src/jtag/core.c
index e57f62db7df1012979e05e51d06b318adaf0096b..84e93967753bd5f94194f7b4fbb0521aff64bb02 100644 (file)
--- a/src/jtag/core.c
+++ b/src/jtag/core.c
@@ -1611,14 +1611,18 @@ static int adapter_khz_to_speed(unsigned khz, int *speed)
 {
        LOG_DEBUG("convert khz to interface specific speed value");
        speed_khz = khz;
-       if (jtag != NULL) {
-               LOG_DEBUG("have interface set up");
-               int speed_div1;
-               int retval = jtag->khz(jtag_get_speed_khz(), &speed_div1);
-               if (ERROR_OK != retval)
-                       return retval;
-               *speed = speed_div1;
+       if (!jtag)
+               return ERROR_OK;
+       LOG_DEBUG("have interface set up");
+       if (!jtag->khz) {
+               LOG_ERROR("Translation from khz to jtag_speed not implemented");
+               return ERROR_FAIL;
        }
+       int speed_div1;
+       int retval = jtag->khz(jtag_get_speed_khz(), &speed_div1);
+       if (ERROR_OK != retval)
+               return retval;
+       *speed = speed_div1;
        return ERROR_OK;
 }
 
@@ -1681,7 +1685,13 @@ int jtag_get_speed_readable(int *khz)
        int retval = jtag_get_speed(&jtag_speed_var);
        if (retval != ERROR_OK)
                return retval;
-       return jtag ? jtag->speed_div(jtag_speed_var, khz) : ERROR_OK;
+       if (!jtag)
+               return ERROR_OK;
+       if (!jtag->speed_div) {
+               LOG_ERROR("Translation from jtag_speed to khz not implemented");
+               return ERROR_FAIL;
+       }
+       return jtag->speed_div(jtag_speed_var, khz);
 }
 
 void jtag_set_verify(bool enable)
@@ -1712,12 +1722,20 @@ int jtag_power_dropout(int *dropout)
                LOG_ERROR("No Valid JTAG Interface Configured.");
                exit(-1);
        }
-       return jtag->power_dropout(dropout);
+       if (jtag->power_dropout)
+               return jtag->power_dropout(dropout);
+
+       *dropout = 0; /* by default we can't detect power dropout */
+       return ERROR_OK;
 }
 
 int jtag_srst_asserted(int *srst_asserted)
 {
-       return jtag->srst_asserted(srst_asserted);
+       if (jtag->srst_asserted)
+               return jtag->srst_asserted(srst_asserted);
+
+       *srst_asserted = 0; /* by default we can't detect srst asserted */
+       return ERROR_OK;
 }
 
 enum reset_types jtag_get_reset_config(void)