Zach Welch <zw@superlucidity.net> refactor

git-svn-id: svn://svn.berlios.de/openocd/trunk@1498 b42882b7-edfa-0310-969c-e2dbd0fdcd60

src/jtag/jlink.c

@@ -230,8 +230,13 @@ static int jlink_speed(int speed)
 {
 	int result;
 
-	if (speed <= JLINK_MAX_SPEED)
+	if (speed > JLINK_MAX_SPEED)
 	{
+		LOG_INFO("Ignoring speed request: %dkHz exceeds %dkHz maximum",
+				speed, JLINK_MAX_SPEED);
+		return ERROR_OK;
+	}
+
 	/* check for RTCK setting */
 	if (speed == 0)
 		speed = -1;
@@ -241,21 +246,11 @@ static int jlink_speed(int speed)
 	usb_out_buffer[2] = (speed >> 8) & 0xff;
 
 	result = jlink_usb_write(jlink_jtag_handle, 3);
-
+	if (result != 3)
-		if (result == 3)
-		{
-			return ERROR_OK;
-		}
-		else
 	{
 		LOG_ERROR("J-Link setting speed failed (%d)", result);
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
-	}
-	else
-	{
-		LOG_INFO("Requested speed %dkHz exceeds maximum of %dkHz, ignored", speed, JLINK_MAX_SPEED);
-	}
 
 	return ERROR_OK;
 }
@@ -485,10 +480,14 @@ static int jlink_get_status(void)
 	int result;
 
 	jlink_simple_command(EMU_CMD_GET_STATE);
-	result = jlink_usb_read(jlink_jtag_handle, 8);
 
-	if (result == 8)
+	result = jlink_usb_read(jlink_jtag_handle, 8);
+	if (result != 8)
 	{
+		LOG_ERROR("J-Link command EMU_CMD_GET_STATE failed (%d)\n", result);
+		return ERROR_JTAG_DEVICE_ERROR;
+	}
+
 	int vref = usb_in_buffer[0] + (usb_in_buffer[1] << 8);
 	LOG_INFO("Vref = %d.%d TCK = %d TDI = %d TDO = %d TMS = %d SRST = %d TRST = %d\n", \
 		vref / 1000, vref % 1000, \
@@ -496,14 +495,7 @@ static int jlink_get_status(void)
 		usb_in_buffer[5], usb_in_buffer[6], usb_in_buffer[7]);
 
 	if (vref < 1500)
-		{
 		LOG_ERROR("Vref too low. Check Target Power\n");
-		}
-	}
-	else
-	{
-		LOG_ERROR("J-Link command EMU_CMD_GET_STATE failed (%d)\n", result);
-	}
 
 	return ERROR_OK;
 }
@@ -511,27 +503,32 @@ static int jlink_get_status(void)
 static int jlink_get_version_info(void)
 {
 	int result;
-	int len = 0;
+	int len;
 
 	/* query hardware version */
 	jlink_simple_command(EMU_CMD_VERSION);
-	result = jlink_usb_read(jlink_jtag_handle, 2);
 
-	if (result == 2)
+	result = jlink_usb_read(jlink_jtag_handle, 2);
+	if (2 != result)
 	{
+		LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n",
+				result);
+		return ERROR_JTAG_DEVICE_ERROR;
+	}
+
 	len = buf_get_u32(usb_in_buffer, 0, 16);
 	result = jlink_usb_read(jlink_jtag_handle, len);
-
+	if (result != len)
-		if (result == len)
 	{
+		LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n",
+				result);
+		return ERROR_JTAG_DEVICE_ERROR;
+	}
+
 	usb_in_buffer[result] = 0;
 	LOG_INFO("%s", (char *)usb_in_buffer);
-			return ERROR_OK;
-		}
-	}
 
-	LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
+	return ERROR_OK;
-	return ERROR_JTAG_DEVICE_ERROR;
 }
 
 static int jlink_handle_jlink_info_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
@@ -551,7 +548,7 @@ static int jlink_handle_jlink_info_command(struct command_context_s *cmd_ctx, ch
 /* 2048 is the max value we can use here */
 #define JLINK_TAP_BUFFER_SIZE 2048
 
-static int tap_length;
+static unsigned tap_length;
 static u8 tms_buffer[JLINK_TAP_BUFFER_SIZE];
 static u8 tdi_buffer[JLINK_TAP_BUFFER_SIZE];
 static u8 tdo_buffer[JLINK_TAP_BUFFER_SIZE];
@@ -593,40 +590,32 @@ static void jlink_tap_append_step(int tms, int tdi)
 	last_tms = tms;
 	int index = tap_length / 8;
 
-	if (index < JLINK_TAP_BUFFER_SIZE)
+	if (index >= JLINK_TAP_BUFFER_SIZE)
 	{
+		LOG_ERROR("jlink_tap_append_step: overflow");
+		exit(-1);
+	}
+
 	int bit_index = tap_length % 8;
 	u8 bit = 1 << bit_index;
 
 	if (tms)
-		{
 		tms_buffer[index] |= bit;
-		}
 	else
-		{
 		tms_buffer[index] &= ~bit;
-		}
 
 	if (tdi)
-		{
 		tdi_buffer[index] |= bit;
-		}
 	else
-		{
 		tdi_buffer[index] &= ~bit;
-		}
 
 	tap_length++;
 }
-	else
-	{
-		LOG_ERROR("jlink_tap_append_step, overflow");
-	}
-}
 
 static void jlink_tap_append_scan(int length, u8 *buffer, scan_command_t *command)
 {
-	pending_scan_result_t *pending_scan_result = &pending_scan_results_buffer[pending_scan_results_length];
+	pending_scan_result_t *pending_scan_result =
+		&pending_scan_results_buffer[pending_scan_results_length];
 	int i;
 
 	pending_scan_result->first = tap_length;
@@ -636,7 +625,9 @@ static void jlink_tap_append_scan(int length, u8 *buffer, scan_command_t *comman
 
 	for (i = 0; i < length; i++)
 	{
-		jlink_tap_append_step((i < length-1 ? 0 : 1), (buffer[i/8] >> (i%8)) & 1);
+		int tms = i < length - 1 ? 0 : 1;
+		int tdi = buffer[i / 8] & (1 << (i % 8));
+		jlink_tap_append_step(tms, tdi);
 	}
 	pending_scan_results_length++;
 }
@@ -651,8 +642,9 @@ static int jlink_tap_execute(void)
 	int i;
 	int result;
 
-	if (tap_length > 0)
+	if (!tap_length)
-	{
+		return ERROR_OK;
+
 	/* Pad last byte so that tap_length is divisible by 8 */
 	while (tap_length % 8 != 0)
 	{
@@ -682,13 +674,16 @@ static int jlink_tap_execute(void)
 
 	result = jlink_usb_message(jlink_jtag_handle, 4 + 2 * byte_length, byte_length);
 
-		if (result == byte_length)
+	if (result != byte_length)
 	{
-			for (i = 0; i < byte_length; i++)
+		LOG_ERROR("jlink_tap_execute, wrong result %d (expected %d)",
-			{
+				result, byte_length);
-				tdo_buffer[i] = usb_in_buffer[i];
+		return ERROR_JTAG_QUEUE_FAILED;
 	}
 
+	for (i = 0; i < byte_length; i++)
+		tdo_buffer[i] = usb_in_buffer[i];
+
 	for (i = 0; i < pending_scan_results_length; i++)
 	{
 		pending_scan_result_t *pending_scan_result = &pending_scan_results_buffer[i];
@@ -717,15 +712,8 @@ static int jlink_tap_execute(void)
 			free(pending_scan_result->buffer);
 		}
 	}
-		}
-		else
-		{
-			LOG_ERROR("jlink_tap_execute, wrong result %d, expected %d", result, byte_length);
-			return ERROR_JTAG_QUEUE_FAILED;
-		}
 
 	jlink_tap_init();
-	}
 
 	return ERROR_OK;
 }
@@ -792,60 +780,49 @@ static int jlink_usb_message(jlink_jtag_t *jlink_jtag, int out_length, int in_le
 	int result2;
 
 	result = jlink_usb_write(jlink_jtag, out_length);
-	if (result == out_length)
+	if (result != out_length)
 	{
+		LOG_ERROR("usb_bulk_write failed (requested=%d, result=%d)",
+				out_length, result);
+		return ERROR_JTAG_DEVICE_ERROR;
+	}
+
 	result = jlink_usb_read(jlink_jtag, in_length);
-		if (result == in_length || result == in_length+1)
+	if ((result != in_length) && (result != in_length + 1))
 	{
+		LOG_ERROR("usb_bulk_read failed (requested=%d, result=%d)",
+				in_length, result);
+		return ERROR_JTAG_DEVICE_ERROR;
+	}
+
 	if (result == in_length)
 	{
 		/* Must read the result from the EMU too */
 		result2 = jlink_usb_read_emu_result(jlink_jtag);
-				if (1 == result2)
+		if (1 != result2)
 		{
+			LOG_ERROR("jlink_usb_read_emu_result failed "
+				"(requested=1, result=%d)", result2);
+			return ERROR_JTAG_DEVICE_ERROR;
+		}
+
 		/* Check the result itself */
-					if (0 == usb_emu_result_buffer[0])
+		result2 = usb_emu_result_buffer[0];
+	}
+	else
 	{
+		/* Save the result, then remove it from return value */
+		result2 = usb_in_buffer[result--];
+	}
+
+	if (result2)
+	{
+		LOG_ERROR("jlink_usb_message failed with result=%d)", result2);
+		return ERROR_JTAG_DEVICE_ERROR;
+	}
+
 	return result;
 }
-					else
-					{
-						LOG_ERROR("jlink_usb_read_emu_result (requested=0, result=%d)", usb_emu_result_buffer[0]);
-						return -1;
-					}
-				}
-				else
-				{
-					LOG_ERROR("jlink_usb_read_emu_result len (requested=1, result=%d)", result2);
-					return -1;
-				}
-			}
-			else
-			{
-				/* Check the result itself */
-				if (0 == usb_in_buffer[result-1])
-				{
-					return result-1;
-				}
-				else
-				{
-					LOG_ERROR("jlink_usb_read_emu_result (requested=0, result=%d)", usb_in_buffer[result]);
-					return -1;
-				}
-			}
-		}
-		else
-		{
-			LOG_ERROR("usb_bulk_read failed (requested=%d, result=%d)", in_length, result);
-			return -1;
-		}
-	}
-	else
-	{
-		LOG_ERROR("usb_bulk_write failed (requested=%d, result=%d)", out_length, result);
-		return -1;
-	}
-}
 
 /* calls the given usb_bulk_* function, allowing for the data to trickle in with some timeouts  */
 static int usb_bulk_with_retries(