swd: remove unused API frequency()

The specific SWD API to change/query the adapter speed is never
called because the equivalent JTAG API is used in place of it.
In the restructure of struct jtag_interface, the JTAG API is
promoted as global adapter API, thus a specific SWD one is not
anymore required.

Change-Id: I1e810d255b4dfcd5791b4fac8ae1260c31a057fd
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/4891
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>

src/jtag/drivers/cmsis_dap_usb.c

@@ -1653,15 +1653,6 @@ static int cmsis_dap_khz(int khz, int *jtag_speed)
 	return ERROR_OK;
 }
 
-static int_least32_t cmsis_dap_swd_frequency(int_least32_t hz)
-{
-	if (hz > 0)
-		cmsis_dap_speed(hz / 1000);
-
-	return hz;
-}
-
-
 COMMAND_HANDLER(cmsis_dap_handle_info_command)
 {
 	if (cmsis_dap_get_version_info() == ERROR_OK)
@@ -1790,7 +1781,6 @@ static const struct command_registration cmsis_dap_command_handlers[] = {
 
 static const struct swd_driver cmsis_dap_swd_driver = {
 	.init = cmsis_dap_swd_init,
-	.frequency = cmsis_dap_swd_frequency,
 	.switch_seq = cmsis_dap_swd_switch_seq,
 	.read_reg = cmsis_dap_swd_read_reg,
 	.write_reg = cmsis_dap_swd_write_reg,

src/jtag/drivers/ftdi.c

@@ -1203,14 +1203,6 @@ static void ftdi_swd_write_reg(uint8_t cmd, uint32_t value, uint32_t ap_delay_cl
 	ftdi_swd_queue_cmd(cmd, NULL, value, ap_delay_clk);
 }
 
-static int_least32_t ftdi_swd_frequency(int_least32_t hz)
-{
-	if (hz > 0)
-		freq = mpsse_set_frequency(mpsse_ctx, hz);
-
-	return freq;
-}
-
 static int ftdi_swd_switch_seq(enum swd_special_seq seq)
 {
 	switch (seq) {
@@ -1239,7 +1231,6 @@ static int ftdi_swd_switch_seq(enum swd_special_seq seq)
 
 static const struct swd_driver ftdi_swd = {
 	.init = ftdi_swd_init,
-	.frequency = ftdi_swd_frequency,
 	.switch_seq = ftdi_swd_switch_seq,
 	.read_reg = ftdi_swd_read_reg,
 	.write_reg = ftdi_swd_write_reg,

src/jtag/drivers/jlink.c

@@ -1929,14 +1929,6 @@ static void jlink_swd_read_reg(uint8_t cmd, uint32_t *value, uint32_t ap_delay_c
 	jlink_swd_queue_cmd(cmd, value, 0, ap_delay_clk);
 }
 
-static int_least32_t jlink_swd_frequency(int_least32_t hz)
-{
-	if (hz > 0)
-		jlink_speed(hz / 1000);
-
-	return hz;
-}
-
 /***************************************************************************/
 /* J-Link tap functions */
 
@@ -2212,7 +2204,6 @@ static void jlink_swd_queue_cmd(uint8_t cmd, uint32_t *dst, uint32_t data, uint3
 
 static const struct swd_driver jlink_swd = {
 	.init = &jlink_swd_init,
-	.frequency = &jlink_swd_frequency,
 	.switch_seq = &jlink_swd_switch_seq,
 	.read_reg = &jlink_swd_read_reg,
 	.write_reg = &jlink_swd_write_reg,

src/jtag/drivers/vsllink.c

@@ -956,7 +956,6 @@ static const char * const vsllink_transports[] = {"jtag", "swd", NULL};
 
 static const struct swd_driver vsllink_swd_driver = {
 	.init = vsllink_swd_init,
-	.frequency = vsllink_swd_frequency,
 	.switch_seq = vsllink_swd_switch_seq,
 	.read_reg = vsllink_swd_read_reg,
 	.write_reg = vsllink_swd_write_reg,

src/jtag/drivers/xds110.c

@@ -1925,13 +1925,6 @@ static int xds110_khz(int khz, int *jtag_speed)
 	return ERROR_OK;
 }
 
-static int_least32_t xds110_swd_frequency(int_least32_t hz)
-{
-	if (hz > 0)
-		xds110_speed(hz / 1000);
-	return hz;
-}
-
 COMMAND_HANDLER(xds110_handle_info_command)
 {
 	xds110_show_info();
@@ -2032,7 +2025,6 @@ static const struct command_registration xds110_command_handlers[] = {
 
 static const struct swd_driver xds110_swd_driver = {
 	.init = xds110_swd_init,
-	.frequency = xds110_swd_frequency,
 	.switch_seq = xds110_swd_switch_seq,
 	.read_reg = xds110_swd_read_reg,
 	.write_reg = xds110_swd_write_reg,

src/jtag/swd.h

@@ -232,24 +232,6 @@ struct swd_driver {
 	 */
 	int (*init)(void);
 
-	/**
-	 * Set the SWCLK frequency of the SWD link.
-	 *
-	 * The driver should round the desired value, downwards if possible, to
-	 * the nearest supported frequency. A negative value should be ignored
-	 * and can be used to query the current setting. If the driver does not
-	 * support a variable frequency a fixed, nominal, value should be
-	 * returned.
-	 *
-	 * If the frequency is increased, it must not apply before the currently
-	 * queued transactions are executed. If the frequency is lowered, it may
-	 * apply immediately.
-	 *
-	 * @param hz The desired frequency in Hz.
-	 * @return The actual resulting frequency after rounding.
-	 */
-	int_least32_t (*frequency)(int_least32_t hz);
-
 	/**
 	 * Queue a special SWDIO sequence.
 	 *