jtag/drivers/openjtag: Add support for Cypress CY7C65215

The Cypress CY7C65215 Dual Channel USB-Serial Bridge Controller [1]
understands the OpenJTAG protocol over a proprietary USB interface.

This patch adds support for the CY7C65215 to the openjtag interface
driver.  A new configuration option, `openjtag_variant`, allows to
select the transport to use.

Libusb (1.x or 0.1) is now a hard dependency of the openjtag driver.
This should not be a big issue as libftdi also depends on it.

[1] http://www.cypress.com/?rID=82870

Change-Id: I55ffb3fd9e006eb311e405d9fb836bb119644bfd
Signed-off-by: Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Reviewed-on: http://openocd.zylin.com/2805
Tested-by: jenkins
Reviewed-by: Jiri Kastner <cz172638@gmail.com>
Reviewed-by: Paul Fertser <fercerpav@gmail.com>

3 files changed, 275 insertions, 26 deletions

diff --git a/configure.ac b/configure.ac
index a47a1841..1e6be141 100644
--- a/configure.ac
+++ b/configure.ac
@@ -782,6 +782,13 @@ PROCESS_ADAPTERS([USB0_ADAPTERS], [$use_libusb0 = yes], [libusb-0.1])
 PROCESS_ADAPTERS([HIDAPI_ADAPTERS], [$use_hidapi = yes], [hidapi])
 PROCESS_ADAPTERS([LIBJAYLINK_ADAPTERS], [$use_libusb1 = yes -a $use_internal_libjaylink = yes -o $HAVE_LIBJAYLINK = yes], [libusb-1.x or libjaylink-0.1])
 
+if test $build_openjtag = yes; then
+	if test $use_libusb1 != yes -a $use_libusb0 != yes; then
+		AC_MSG_ERROR([libusb-1.x or libusb-0.1 is required for the OpenJTAG Programmer])
+		build_openjtag=no
+	fi
+fi
+
 if test $enable_stlink != no -o $enable_ti_icdi != no; then
 	AC_DEFINE([BUILD_HLADAPTER], [1], [1 if you want the High Level JTAG driver.])
 else
diff --git a/doc/openocd.texi b/doc/openocd.texi
index 1cca4ab1..7c2152b1 100644
--- a/doc/openocd.texi
+++ b/doc/openocd.texi
@@ -2912,6 +2912,27 @@ pinout.
 
 @end deffn
 
+@deffn {Interface Driver} {openjtag}
+OpenJTAG compatible USB adapter.
+This defines some driver-specific commands:
+
+@deffn {Config Command} {openjtag_variant} variant
+Specifies the variant of the OpenJTAG adapter (see @uref{http://www.openjtag.org/}).
+Currently valid @var{variant} values include:
+
+@itemize @minus
+@item @b{standard} Standard variant (default).
+@item @b{cy7c65215} Cypress CY7C65215 Dual Channel USB-Serial Bridge Controller
+(see @uref{http://www.cypress.com/?rID=82870}).
+@end itemize
+@end deffn
+
+@deffn {Config Command} {openjtag_device_desc} string
+The USB device description string of the adapter.
+This value is only used with the standard variant.
+@end deffn
+@end deffn
+
 @section Transport Configuration
 @cindex Transport
 As noted earlier, depending on the version of OpenOCD you use,
diff --git a/src/jtag/drivers/openjtag.c b/src/jtag/drivers/openjtag.c
index 5d1084ce..bb0ff74d 100644
--- a/src/jtag/drivers/openjtag.c
+++ b/src/jtag/drivers/openjtag.c
@@ -1,6 +1,10 @@
 /*******************************************************************************
  *   Driver for OpenJTAG Project (www.openjtag.org)                            *
- *   Compatible with libftdi driver.                                           *
+ *   Compatible with libftdi and ftd2xx drivers.                               *
+ *                                                                             *
+ *   Cypress CY7C65215 support                                                 *
+ *   Copyright (C) 2015 Vianney le Clément de Saint-Marcq, Essensium NV        *
+ *                      <vianney.leclement@essensium.com>                      *
  *                                                                             *
  *   Copyright (C) 2010 by Ivan Meleca <mileca@gmail.com>                      *
  *                                                                             *
@@ -41,7 +45,18 @@
 
 #include <jtag/interface.h>
 #include <jtag/commands.h>
-#include "usb_common.h"
+#include "libusb_common.h"
+
+static enum {
+	OPENJTAG_VARIANT_STANDARD,
+	OPENJTAG_VARIANT_CY7C65215,
+} openjtag_variant = OPENJTAG_VARIANT_STANDARD;
+
+static const char * const openjtag_variant_names[] = {
+	"standard",
+	"cy7c65215",
+	NULL
+};
 
 /*
  * OpenJTAG-OpenOCD state conversion
@@ -96,10 +111,24 @@ static uint8_t usb_rx_buf[OPENJTAG_BUFFER_SIZE];
 static struct openjtag_scan_result openjtag_scan_result_buffer[OPENJTAG_MAX_PENDING_RESULTS];
 static int openjtag_scan_result_count;
 
-/* Openocd usb handler */
-struct openocd {
-	struct usb_dev_handle *usb_handle;
-};
+static jtag_libusb_device_handle *usbh;
+
+/* CY7C65215 model only */
+#define CY7C65215_JTAG_REQUEST  0x40  /* bmRequestType: vendor host-to-device */
+#define CY7C65215_JTAG_ENABLE   0xD0  /* bRequest: enable JTAG */
+#define CY7C65215_JTAG_DISABLE  0xD1  /* bRequest: disable JTAG */
+#define CY7C65215_JTAG_READ     0xD2  /* bRequest: read buffer */
+#define CY7C65215_JTAG_WRITE    0xD3  /* bRequest: write buffer */
+
+#define CY7C65215_USB_TIMEOUT   100
+
+static const uint16_t cy7c65215_vids[] = {0x04b4, 0};
+static const uint16_t cy7c65215_pids[] = {0x0007, 0};
+
+#define CY7C65215_JTAG_CLASS     0xff
+#define CY7C65215_JTAG_SUBCLASS  0x04
+
+static unsigned int ep_in, ep_out;
 
 #ifdef _DEBUG_USB_COMMS_
 
@@ -185,7 +214,7 @@ static int8_t openjtag_get_tap_state(int8_t state)
 	}
 }
 
-static int openjtag_buf_write(
+static int openjtag_buf_write_standard(
 	uint8_t *buf, int size, uint32_t *bytes_written)
 {
 	int retval;
@@ -205,8 +234,54 @@ static int openjtag_buf_write(
 	return ERROR_OK;
 }
 
-static int openjtag_buf_read(uint8_t *buf, uint32_t qty, uint32_t *bytes_read)
+static int openjtag_buf_write_cy7c65215(
+	uint8_t *buf, int size, uint32_t *bytes_written)
+{
+	int ret;
+
+#ifdef _DEBUG_USB_COMMS_
+	openjtag_debug_buffer(buf, size, DEBUG_TYPE_WRITE);
+#endif
+
+	if (size == 0) {
+		*bytes_written = 0;
+		return ERROR_OK;
+	}
+
+	ret = jtag_libusb_control_transfer(usbh, CY7C65215_JTAG_REQUEST,
+									   CY7C65215_JTAG_WRITE, size, 0,
+									   NULL, 0, CY7C65215_USB_TIMEOUT);
+	if (ret < 0) {
+		LOG_ERROR("vendor command failed, error %d", ret);
+		return ERROR_JTAG_DEVICE_ERROR;
+	}
+
+	ret = jtag_libusb_bulk_write(usbh, ep_out, (char *)buf, size,
+								 CY7C65215_USB_TIMEOUT);
+	if (ret < 0) {
+		LOG_ERROR("bulk write failed, error %d", ret);
+		return ERROR_JTAG_DEVICE_ERROR;
+	}
+	*bytes_written = ret;
+
+	return ERROR_OK;
+}
+
+static int openjtag_buf_write(
+	uint8_t *buf, int size, uint32_t *bytes_written)
+{
+	switch (openjtag_variant) {
+	case OPENJTAG_VARIANT_CY7C65215:
+		return openjtag_buf_write_cy7c65215(buf, size, bytes_written);
+	default:
+		return openjtag_buf_write_standard(buf, size, bytes_written);
+	}
+}
+
+static int openjtag_buf_read_standard(
+	uint8_t *buf, uint32_t qty, uint32_t *bytes_read)
 {
+
 	int retval;
 	int timeout = 5;
 
@@ -231,6 +306,50 @@ static int openjtag_buf_read(uint8_t *buf, uint32_t qty, uint32_t *bytes_read)
 	return ERROR_OK;
 }
 
+static int openjtag_buf_read_cy7c65215(
+	uint8_t *buf, uint32_t qty, uint32_t *bytes_read)
+{
+	int ret;
+
+	if (qty == 0) {
+		*bytes_read = 0;
+		goto out;
+	}
+
+	ret = jtag_libusb_control_transfer(usbh, CY7C65215_JTAG_REQUEST,
+									   CY7C65215_JTAG_READ, qty, 0,
+									   NULL, 0, CY7C65215_USB_TIMEOUT);
+	if (ret < 0) {
+		LOG_ERROR("vendor command failed, error %d", ret);
+		return ERROR_JTAG_DEVICE_ERROR;
+	}
+
+	ret = jtag_libusb_bulk_read(usbh, ep_in, (char *)buf, qty,
+								CY7C65215_USB_TIMEOUT);
+	if (ret < 0) {
+		LOG_ERROR("bulk read failed, error %d", ret);
+		return ERROR_JTAG_DEVICE_ERROR;
+	}
+	*bytes_read = ret;
+
+out:
+#ifdef _DEBUG_USB_COMMS_
+	openjtag_debug_buffer(buf, *bytes_read, DEBUG_TYPE_READ);
+#endif
+
+	return ERROR_OK;
+}
+
+static int openjtag_buf_read(uint8_t *buf, uint32_t qty, uint32_t *bytes_read)
+{
+	switch (openjtag_variant) {
+	case OPENJTAG_VARIANT_CY7C65215:
+		return openjtag_buf_read_cy7c65215(buf, qty, bytes_read);
+	default:
+		return openjtag_buf_read_standard(buf, qty, bytes_read);
+	}
+}
+
 static int openjtag_sendcommand(uint8_t cmd)
 {
 	uint32_t written;
@@ -275,16 +394,10 @@ static int openjtag_speed(int speed)
 	return ERROR_OK;
 }
 
-static int openjtag_init(void)
+static int openjtag_init_standard(void)
 {
 	uint8_t latency_timer;
 
-	usb_tx_buf_offs = 0;
-	usb_rx_buf_len = 0;
-	openjtag_scan_result_count = 0;
-
-	LOG_DEBUG("'openjtag' interface using libftdi");
-
 	/* Open by device description */
 	if (openjtag_device_desc == NULL) {
 		LOG_WARNING("no openjtag device description specified, "
@@ -330,16 +443,70 @@ static int openjtag_init(void)
 		return ERROR_JTAG_INIT_FAILED;
 	}
 
-	/* OpenJTAG speed */
-	openjtag_sendcommand(0xE0); /*Start at slowest adapter speed*/
+	return ERROR_OK;
+}
+
+static int openjtag_init_cy7c65215(void)
+{
+	int ret;
+
+	usbh = NULL;
+	ret = jtag_libusb_open(cy7c65215_vids, cy7c65215_pids, NULL, &usbh);
+	if (ret != ERROR_OK) {
+		LOG_ERROR("unable to open cy7c65215 device");
+		goto err;
+	}
+
+	ret = jtag_libusb_choose_interface(usbh, &ep_in, &ep_out,
+									   CY7C65215_JTAG_CLASS,
+									   CY7C65215_JTAG_SUBCLASS, -1);
+	if (ret != ERROR_OK) {
+		LOG_ERROR("unable to claim JTAG interface");
+		goto err;
+	}
 
-	/* MSB */
-	openjtag_sendcommand(0x75);
+	ret = jtag_libusb_control_transfer(usbh,
+									   CY7C65215_JTAG_REQUEST,
+									   CY7C65215_JTAG_ENABLE,
+									   0, 0, NULL, 0, CY7C65215_USB_TIMEOUT);
+	if (ret < 0) {
+		LOG_ERROR("could not enable JTAG module");
+		goto err;
+	}
 
 	return ERROR_OK;
+
+err:
+	if (usbh != NULL)
+		jtag_libusb_close(usbh);
+	return ERROR_JTAG_INIT_FAILED;
 }
 
-static int openjtag_quit(void)
+static int openjtag_init(void)
+{
+	int ret;
+
+	usb_tx_buf_offs = 0;
+	usb_rx_buf_len = 0;
+	openjtag_scan_result_count = 0;
+
+	switch (openjtag_variant) {
+	case OPENJTAG_VARIANT_CY7C65215:
+		ret = openjtag_init_cy7c65215();
+		break;
+	default:
+		ret = openjtag_init_standard();
+	}
+	if (ret != ERROR_OK)
+		return ret;
+
+	openjtag_speed(375); /* Start at slowest adapter speed */
+	openjtag_sendcommand(0x75); /* MSB */
+
+	return ERROR_OK;
+}
+
+static int openjtag_quit_standard(void)
 {
 	ftdi_usb_close(&ftdic);
 	ftdi_deinit(&ftdic);
@@ -347,6 +514,32 @@ static int openjtag_quit(void)
 	return ERROR_OK;
 }
 
+static int openjtag_quit_cy7c65215(void)
+{
+	int ret;
+
+	ret = jtag_libusb_control_transfer(usbh,
+									   CY7C65215_JTAG_REQUEST,
+									   CY7C65215_JTAG_DISABLE,
+									   0, 0, NULL, 0, CY7C65215_USB_TIMEOUT);
+	if (ret < 0)
+		LOG_WARNING("could not disable JTAG module");
+
+	jtag_libusb_close(usbh);
+
+	return ERROR_OK;
+}
+
+static int openjtag_quit(void)
+{
+	switch (openjtag_variant) {
+	case OPENJTAG_VARIANT_CY7C65215:
+		return openjtag_quit_cy7c65215();
+	default:
+		return openjtag_quit_standard();
+	}
+}
+
 static void openjtag_write_tap_buffer(void)
 {
 	uint32_t written;
@@ -379,8 +572,8 @@ static int openjtag_execute_tap_queue(void)
 
 			uint8_t *buffer = openjtag_scan_result_buffer[res_count].buffer;
 
-			while (len) {
-				if (len <= 8) {
+			while (len > 0) {
+				if (len <= 8 && openjtag_variant != OPENJTAG_VARIANT_CY7C65215) {
 					DEBUG_JTAG_IO("bits < 8 buf = 0x%X, will be 0x%X",
 						usb_rx_buf[rx_offs], usb_rx_buf[rx_offs] >> (8 - len));
 					buffer[count] = usb_rx_buf[rx_offs] >> (8 - len);
@@ -567,11 +760,14 @@ static void openjtag_execute_runtest(struct jtag_command *cmd)
 	if (cmd->cmd.runtest->num_cycles > 16)
 		LOG_WARNING("num_cycles > 16 on run test");
 
-	uint8_t command;
-	command = 7;
-	command |= ((cmd->cmd.runtest->num_cycles - 1) & 0x0F) << 4;
+	if (openjtag_variant != OPENJTAG_VARIANT_CY7C65215 ||
+		cmd->cmd.runtest->num_cycles) {
+		uint8_t command;
+		command = 7;
+		command |= ((cmd->cmd.runtest->num_cycles - 1) & 0x0F) << 4;
 
-	openjtag_add_byte(command);
+		openjtag_add_byte(command);
+	}
 
 	tap_set_end_state(end_state);
 	if (tap_get_end_state() != tap_get_state()) {
@@ -659,6 +855,24 @@ COMMAND_HANDLER(openjtag_handle_device_desc_command)
 	return ERROR_OK;
 }
 
+COMMAND_HANDLER(openjtag_handle_variant_command)
+{
+	if (CMD_ARGC == 1) {
+		const char * const *name = openjtag_variant_names;
+		int variant = 0;
+		for (; *name; name++, variant++) {
+			if (strcasecmp(CMD_ARGV[0], *name) == 0) {
+				openjtag_variant = variant;
+				return ERROR_OK;
+			}
+		}
+		LOG_ERROR("unknown openjtag variant '%s'", CMD_ARGV[0]);
+	} else {
+		LOG_ERROR("require exactly one argument to "
+				"openjtag_variant <variant>");
+	}
+	return ERROR_OK;
+}
 
 static const struct command_registration openjtag_command_handlers[] = {
 	{
@@ -668,6 +882,13 @@ static const struct command_registration openjtag_command_handlers[] = {
 		.help = "set the USB device description of the OpenJTAG",
 		.usage = "description-string",
 	},
+	{
+		.name = "openjtag_variant",
+		.handler = openjtag_handle_variant_command,
+		.mode = COMMAND_CONFIG,
+		.help = "set the OpenJTAG variant",
+		.usage = "variant-string",
+	},
 	COMMAND_REGISTRATION_DONE
 };