diff options
| -rw-r--r-- | Documentation/usb/usb-serial.txt | 11 | ||||
| -rw-r--r-- | drivers/usb/serial/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/usb/serial/Makefile | 1 | ||||
| -rw-r--r-- | drivers/usb/serial/ch341.c | 352 |
4 files changed, 374 insertions, 0 deletions
diff --git a/Documentation/usb/usb-serial.txt b/Documentation/usb/usb-serial.txt index 5b635ae..4e0b62b 100644 --- a/Documentation/usb/usb-serial.txt +++ b/Documentation/usb/usb-serial.txt @@ -428,6 +428,17 @@ Options supported: See http://www.uuhaus.de/linux/palmconnect.html for up-to-date information on this driver. +Winchiphead CH341 Driver + + This driver is for the Winchiphead CH341 USB-RS232 Converter. This chip + also implements an IEEE 1284 parallel port, I2C and SPI, but that is not + supported by the driver. The protocol was analyzed from the behaviour + of the Windows driver, no datasheet is available at present. + The manufacturer's website: http://www.winchiphead.com/. + For any questions or problems with this driver, please contact + frank@kingswood-consulting.co.uk. + + Generic Serial driver If your device is not one of the above listed devices, compatible with diff --git a/drivers/usb/serial/Kconfig b/drivers/usb/serial/Kconfig index 43d6db6..99fefed 100644 --- a/drivers/usb/serial/Kconfig +++ b/drivers/usb/serial/Kconfig @@ -92,6 +92,16 @@ config USB_SERIAL_BELKIN To compile this driver as a module, choose M here: the module will be called belkin_sa. +config USB_SERIAL_CH341 + tristate "USB Winchiphead CH341 Single Port Serial Driver" + depends on USB_SERIAL + help + Say Y here if you want to use a Winchiphead CH341 single port + USB to serial adapter. + + To compile this driver as a module, choose M here: the + module will be called ch341. + config USB_SERIAL_WHITEHEAT tristate "USB ConnectTech WhiteHEAT Serial Driver" depends on USB_SERIAL diff --git a/drivers/usb/serial/Makefile b/drivers/usb/serial/Makefile index 07a976e..d6fb384 100644 --- a/drivers/usb/serial/Makefile +++ b/drivers/usb/serial/Makefile @@ -15,6 +15,7 @@ obj-$(CONFIG_USB_SERIAL_AIRCABLE) += aircable.o obj-$(CONFIG_USB_SERIAL_AIRPRIME) += airprime.o obj-$(CONFIG_USB_SERIAL_ARK3116) += ark3116.o obj-$(CONFIG_USB_SERIAL_BELKIN) += belkin_sa.o +obj-$(CONFIG_USB_SERIAL_CH341) += ch341.o obj-$(CONFIG_USB_SERIAL_CP2101) += cp2101.o obj-$(CONFIG_USB_SERIAL_CYBERJACK) += cyberjack.o obj-$(CONFIG_USB_SERIAL_CYPRESS_M8) += cypress_m8.o diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c new file mode 100644 index 0000000..eb68106 --- /dev/null +++ b/drivers/usb/serial/ch341.c @@ -0,0 +1,352 @@ +/* + * Copyright 2007, Frank A Kingswood <frank@kingswood-consulting.co.uk> + * + * ch341.c implements a serial port driver for the Winchiphead CH341. + * + * The CH341 device can be used to implement an RS232 asynchronous + * serial port, an IEEE-1284 parallel printer port or a memory-like + * interface. In all cases the CH341 supports an I2C interface as well. + * This driver only supports the asynchronous serial interface. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation. + */ + +#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/serial.h> + +#define DEFAULT_BAUD_RATE 2400 +#define DEFAULT_TIMEOUT 1000 + +static int debug; + +static struct usb_device_id id_table [] = { + { USB_DEVICE(0x4348, 0x5523) }, + { }, +}; +MODULE_DEVICE_TABLE(usb, id_table); + +struct ch341_private { + unsigned baud_rate; + u8 dtr; + u8 rts; +}; + +static int ch341_control_out(struct usb_device *dev, u8 request, + u16 value, u16 index) +{ + int r; + dbg("ch341_control_out(%02x,%02x,%04x,%04x)", USB_DIR_OUT|0x40, + (int)request, (int)value, (int)index); + + r = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), request, + USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT, + value, index, NULL, 0, DEFAULT_TIMEOUT); + + return r; +} + +static int ch341_control_in(struct usb_device *dev, + u8 request, u16 value, u16 index, + char *buf, unsigned bufsize) +{ + int r; + dbg("ch341_control_in(%02x,%02x,%04x,%04x,%p,%u)", USB_DIR_IN|0x40, + (int)request, (int)value, (int)index, buf, (int)bufsize); + + r = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), request, + USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN, + value, index, buf, bufsize, DEFAULT_TIMEOUT); + return r; +} + +int ch341_set_baudrate(struct usb_device *dev, struct ch341_private *priv) +{ + short a, b; + int r; + + dbg("ch341_set_baudrate(%d)", priv->baud_rate); + switch (priv->baud_rate) { + case 2400: + a = 0xd901; + b = 0x0038; + break; + case 4800: + a = 0x6402; + b = 0x001f; + break; + case 9600: + a = 0xb202; + b = 0x0013; + break; + case 19200: + a = 0xd902; + b = 0x000d; + break; + case 38400: + a = 0x6403; + b = 0x000a; + break; + case 115200: + a = 0xcc03; + b = 0x0008; + break; + default: + return -EINVAL; + } + + r = ch341_control_out(dev, 0x9a, 0x1312, a); + if (!r) + r = ch341_control_out(dev, 0x9a, 0x0f2c, b); + + return r; +} + +int ch341_set_handshake(struct usb_device *dev, struct ch341_private *priv) +{ + dbg("ch341_set_handshake(%d,%d)", priv->dtr, priv->rts); + return ch341_control_out(dev, 0xa4, + ~((priv->dtr?1<<5:0)|(priv->rts?1<<6:0)), 0); +} + +int ch341_get_status(struct usb_device *dev) +{ + char *buffer; + int r; + const unsigned size = 8; + + dbg("ch341_get_status()"); + + buffer = kmalloc(size, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + r = ch341_control_in(dev, 0x95, 0x0706, 0, buffer, size); + if ( r < 0) + goto out; + + /* Not having the datasheet for the CH341, we ignore the bytes returned + * from the device. Return error if the device did not respond in time. + */ + r = 0; + +out: kfree(buffer); + return r; +} + +/* -------------------------------------------------------------------------- */ + +int ch341_configure(struct usb_device *dev, struct ch341_private *priv) +{ + char *buffer; + int r; + const unsigned size = 8; + + dbg("ch341_configure()"); + + buffer = kmalloc(size, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + /* expect two bytes 0x27 0x00 */ + r = ch341_control_in(dev, 0x5f, 0, 0, buffer, size); + if (r < 0) + goto out; + + r = ch341_control_out(dev, 0xa1, 0, 0); + if (r < 0) + goto out; + + r = ch341_set_baudrate(dev, priv); + if (r < 0) + goto out; + + /* expect two bytes 0x56 0x00 */ + r = ch341_control_in(dev, 0x95, 0x2518, 0, buffer, size); + if (r < 0) + goto out; + + r = ch341_control_out(dev, 0x9a, 0x2518, 0x0050); + if (r < 0) + goto out; + + /* expect 0xff 0xee */ + r = ch341_get_status(dev); + if (r < 0) + goto out; + + r = ch341_control_out(dev, 0xa1, 0x501f, 0xd90a); + if (r < 0) + goto out; + + r = ch341_set_baudrate(dev, priv); + if (r < 0) + goto out; + + r = ch341_set_handshake(dev, priv); + if (r < 0) + goto out; + + /* expect 0x9f 0xee */ + r = ch341_get_status(dev); + +out: kfree(buffer); + return r; +} + +/* allocate private data */ +static int ch341_attach(struct usb_serial *serial) +{ + struct ch341_private *priv; + int r; + + dbg("ch341_attach()"); + + /* private data */ + priv = kzalloc(sizeof(struct ch341_private), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->baud_rate = DEFAULT_BAUD_RATE; + priv->dtr = 1; + priv->rts = 1; + + r = ch341_configure(serial->dev, priv); + if (r < 0) + goto error; + + usb_set_serial_port_data(serial->port[0], priv); + return 0; + +error: kfree(priv); + return r; +} + +/* open this device, set default parameters */ +static int ch341_open(struct usb_serial_port *port, struct file *filp) +{ + struct usb_serial *serial = port->serial; + struct ch341_private *priv = usb_get_serial_port_data(serial->port[0]); + int r; + + dbg("ch341_open()"); + + priv->baud_rate = DEFAULT_BAUD_RATE; + priv->dtr = 1; + priv->rts = 1; + + r = ch341_configure(serial->dev, priv); + if (r) + goto out; + + r = ch341_set_handshake(serial->dev, priv); + if (r) + goto out; + + r = ch341_set_baudrate(serial->dev, priv); + if (r) + goto out; + + r = usb_serial_generic_open(port, filp); + +out: return r; +} + +/* Old_termios contains the original termios settings and + * tty->termios contains the new setting to be used. + */ +static void ch341_set_termios(struct usb_serial_port *port, + struct ktermios *old_termios) +{ + struct ch341_private *priv = usb_get_serial_port_data(port); + struct tty_struct *tty = port->tty; + unsigned baud_rate; + + dbg("ch341_set_termios()"); + + if (!tty || !tty->termios) + return; + + baud_rate = tty_get_baud_rate(tty); + + switch (baud_rate) { + case 2400: + case 4800: + case 9600: + case 19200: + case 38400: + case 115200: + priv->baud_rate = baud_rate; + break; + default: + dbg("Rate %d not supported, using %d", + baud_rate, DEFAULT_BAUD_RATE); + priv->baud_rate = DEFAULT_BAUD_RATE; + } + + ch341_set_baudrate(port->serial->dev, priv); + + /* Unimplemented: + * (cflag & CSIZE) : data bits [5, 8] + * (cflag & PARENB) : parity {NONE, EVEN, ODD} + * (cflag & CSTOPB) : stop bits [1, 2] + */ +} + +static struct usb_driver ch341_driver = { + .name = "ch341", + .probe = usb_serial_probe, + .disconnect = usb_serial_disconnect, + .id_table = id_table, + .no_dynamic_id = 1, +}; + +static struct usb_serial_driver ch341_device = { + .driver = { + .owner = THIS_MODULE, + .name = "ch341-uart", + }, + .id_table = id_table, + .usb_driver = &ch341_driver, + .num_interrupt_in = NUM_DONT_CARE, + .num_bulk_in = 1, + .num_bulk_out = 1, + .num_ports = 1, + .open = ch341_open, + .set_termios = ch341_set_termios, + .attach = ch341_attach, +}; + +static int __init ch341_init(void) +{ + int retval; + + retval = usb_serial_register(&ch341_device); + if (retval) + return retval; + retval = usb_register(&ch341_driver); + if (retval) + usb_serial_deregister(&ch341_device); + return retval; +} + +static void __exit ch341_exit(void) +{ + usb_deregister(&ch341_driver); + usb_serial_deregister(&ch341_device); +} + +module_init(ch341_init); +module_exit(ch341_exit); +MODULE_LICENSE("GPL"); + +module_param(debug, bool, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(debug, "Debug enabled or not"); + +/* EOF ch341.c */ |