CH340-341驱动源码

USB转串口CH340341驱动源码#include #include #include #include #include #include #include #define DEFAULT_BAUD_RATE 2400static 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, 1000);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, 1000);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?1rts?16:0), 0);int ch341_get_status(struct usb_device *dev)char *buffer;int r = -ENOMEM;const unsigned size = 8;dbg(ch341_get_status();buffer = kmalloc(size, GFP_KERNEL);if (!buffer)goto out;r = ch341_control_in(dev, 0x95, 0x0706, 0, buffer, size);/* return value ignored */r = 0;out:kfree(buffer);return r;/* - */int ch341_configure(struct usb_device *dev, struct ch341_private *priv)char *buffer;int r = -ENOMEM;const unsigned size = 8;dbg(ch341_configure();buffer = kmalloc(size, GFP_KERNEL);if (!buffer)goto out;/* 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 baud_rate = DEFAULT_BAUD_RATE;priv-dtr = 1;priv-rts = 1;r = ch341_configure(serial-dev, priv);if (r port0, priv);return 0;/* 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-port0);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 cflag;unsigned baud_rate;dbg(ch341_set_termios(%p,%p), port, old_termios);if (!port-tty | !port-tty-termios)return;cflag = tty-termios-c_cflag;/* check that they really want us to change something */if (old_termios & cflag = old_termios-c_cflag)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 */ return;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