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authorWesley W. Terpstra <w.terpstra@gsi.de>2013-04-11 17:08:20 +0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-04-11 19:41:56 +0400
commit1157f69bee295987952bf0cbbcbc419d497eb51c (patch)
tree4a1f90df57efc9016314204102efb54d789ff2de /drivers
parent0fcb99898633e5def627833613cf262fe7f30ac4 (diff)
downloadlinux-1157f69bee295987952bf0cbbcbc419d497eb51c.tar.xz
usb-serial: add support for USB Wishbone-serial adapters
Wishbone is an open hardware SoC bus commonly used in FPGA designs. Bus access can be serialized using the Etherbone protocol <http://www.ohwr.org/projects/etherbone-core>. This driver is intended to be used with devices which attach their internal Wishbone bus to a USB serial interface using the Etherbone protocol. A userspace library is required to speak the protocol made available by this driver as ttyUSBx. Signed-off-by: Wesley W. Terpstra <w.terpstra@gsi.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/usb/serial/Kconfig17
-rw-r--r--drivers/usb/serial/Makefile1
-rw-r--r--drivers/usb/serial/wishbone-serial.c95
3 files changed, 113 insertions, 0 deletions
diff --git a/drivers/usb/serial/Kconfig b/drivers/usb/serial/Kconfig
index bf3733629b09..1d55762afbb1 100644
--- a/drivers/usb/serial/Kconfig
+++ b/drivers/usb/serial/Kconfig
@@ -667,6 +667,23 @@ config USB_SERIAL_ZIO
To compile this driver as a module, choose M here: the
module will be called zio.
+config USB_SERIAL_WISHBONE
+ tristate "USB-Wishbone adapter interface driver"
+ help
+ Say Y here if you want to use a USB attached Wishbone bus.
+
+ Wishbone is an open hardware SoC bus commonly used in FPGA
+ designs. Bus access can be serialized using the Etherbone
+ protocol <http://www.ohwr.org/projects/etherbone-core>.
+
+ This driver is intended to be used with devices which attach
+ their internal Wishbone bus to a USB serial interface using
+ the Etherbone protocol. A userspace library is required to
+ speak the protocol made available by this driver as ttyUSBx.
+
+ To compile this driver as a module, choose M here: the
+ module will be called wishbone-serial.
+
config USB_SERIAL_ZTE
tristate "ZTE USB serial driver"
help
diff --git a/drivers/usb/serial/Makefile b/drivers/usb/serial/Makefile
index eaf5ca14dfeb..cec63fa19104 100644
--- a/drivers/usb/serial/Makefile
+++ b/drivers/usb/serial/Makefile
@@ -58,6 +58,7 @@ obj-$(CONFIG_USB_SERIAL_SYMBOL) += symbolserial.o
obj-$(CONFIG_USB_SERIAL_WWAN) += usb_wwan.o
obj-$(CONFIG_USB_SERIAL_TI) += ti_usb_3410_5052.o
obj-$(CONFIG_USB_SERIAL_VISOR) += visor.o
+obj-$(CONFIG_USB_SERIAL_WISHBONE) += wishbone-serial.o
obj-$(CONFIG_USB_SERIAL_WHITEHEAT) += whiteheat.o
obj-$(CONFIG_USB_SERIAL_XIRCOM) += keyspan_pda.o
obj-$(CONFIG_USB_SERIAL_VIVOPAY_SERIAL) += vivopay-serial.o
diff --git a/drivers/usb/serial/wishbone-serial.c b/drivers/usb/serial/wishbone-serial.c
new file mode 100644
index 000000000000..481ec669bf7c
--- /dev/null
+++ b/drivers/usb/serial/wishbone-serial.c
@@ -0,0 +1,95 @@
+/*
+ * USB Wishbone-Serial adapter driver
+ *
+ * Copyright (C) 2013 Wesley W. Terpstra <w.terpstra@gsi.de>
+ * Copyright (C) 2013 GSI Helmholtz Centre for Heavy Ion Research GmbH
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/tty.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/usb/serial.h>
+#include <linux/uaccess.h>
+
+#define GSI_VENDOR_OPENCLOSE 0xB0
+
+static const struct usb_device_id id_table[] = {
+ { USB_DEVICE_AND_INTERFACE_INFO(0x1D50, 0x6062, 0xFF, 0xFF, 0xFF) },
+ { },
+};
+MODULE_DEVICE_TABLE(usb, id_table);
+
+/*
+ * Etherbone must be told that a new stream has begun before data arrives.
+ * This is necessary to restart the negotiation of Wishbone bus parameters.
+ * Similarly, when the stream ends, Etherbone must be told so that the cycle
+ * line can be driven low in the case that userspace failed to do so.
+ */
+static int usb_gsi_openclose(struct usb_serial_port *port, int value)
+{
+ struct usb_device *dev = port->serial->dev;
+
+ return usb_control_msg(
+ dev,
+ usb_sndctrlpipe(dev, 0), /* Send to EP0OUT */
+ GSI_VENDOR_OPENCLOSE,
+ USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE,
+ value, /* wValue = device is open(1) or closed(0) */
+ port->serial->interface->cur_altsetting->desc.bInterfaceNumber,
+ 0, 0, /* There is no data stage */
+ 5000); /* Timeout till operation fails */
+}
+
+static int wishbone_serial_open(struct tty_struct *tty,
+ struct usb_serial_port *port)
+{
+ int retval;
+
+ retval = usb_gsi_openclose(port, 1);
+ if (retval) {
+ dev_err(&port->serial->dev->dev,
+ "Could not mark device as open (%d)\n",
+ retval);
+ return retval;
+ }
+
+ retval = usb_serial_generic_open(tty, port);
+ if (retval)
+ usb_gsi_openclose(port, 0);
+
+ return retval;
+}
+
+static void wishbone_serial_close(struct usb_serial_port *port)
+{
+ usb_serial_generic_close(port);
+ usb_gsi_openclose(port, 0);
+}
+
+static struct usb_serial_driver wishbone_serial_device = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "wishbone_serial",
+ },
+ .id_table = id_table,
+ .num_ports = 1,
+ .open = &wishbone_serial_open,
+ .close = &wishbone_serial_close,
+};
+
+static struct usb_serial_driver * const serial_drivers[] = {
+ &wishbone_serial_device, NULL
+};
+
+module_usb_serial_driver(serial_drivers, id_table);
+
+MODULE_AUTHOR("Wesley W. Terpstra <w.terpstra@gsi.de>");
+MODULE_DESCRIPTION("USB Wishbone-Serial adapter");
+MODULE_LICENSE("GPL");