// SPDX-License-Identifier: GPL-2.0+ /* * USB IR Dongle driver * * Copyright (C) 2001-2002 Greg Kroah-Hartman (greg@kroah.com) * Copyright (C) 2002 Gary Brubaker (xavyer@ix.netcom.com) * Copyright (C) 2010 Johan Hovold (jhovold@gmail.com) * * This driver allows a USB IrDA device to be used as a "dumb" serial device. * This can be useful if you do not have access to a full IrDA stack on the * other side of the connection. If you do have an IrDA stack on both devices, * please use the usb-irda driver, as it contains the proper error checking and * other goodness of a full IrDA stack. * * Portions of this driver were taken from drivers/net/irda/irda-usb.c, which * was written by Roman Weissgaerber , Dag Brattli * , and Jean Tourrilhes * * See Documentation/usb/usb-serial.rst for more information on using this * driver */ #include #include #include #include #include #include #include #include #include #include #include #include #include #define DRIVER_AUTHOR "Greg Kroah-Hartman , Johan Hovold " #define DRIVER_DESC "USB IR Dongle driver" /* if overridden by the user, then use their value for the size of the read and * write urbs */ static int buffer_size; /* if overridden by the user, then use the specified number of XBOFs */ static int xbof = -1; static int ir_startup (struct usb_serial *serial); static int ir_open(struct tty_struct *tty, struct usb_serial_port *port); static int ir_prepare_write_buffer(struct usb_serial_port *port, void *dest, size_t size); static void ir_process_read_urb(struct urb *urb); static void ir_set_termios(struct tty_struct *tty, struct usb_serial_port *port, struct ktermios *old_termios); /* Not that this lot means you can only have one per system */ static u8 ir_baud; static u8 ir_xbof; static u8 ir_add_bof; static const struct usb_device_id ir_id_table[] = { { USB_DEVICE(0x050f, 0x0180) }, /* KC Technology, KC-180 */ { USB_DEVICE(0x08e9, 0x0100) }, /* XTNDAccess */ { USB_DEVICE(0x09c4, 0x0011) }, /* ACTiSys ACT-IR2000U */ { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, USB_SUBCLASS_IRDA, 0) }, { } /* Terminating entry */ }; MODULE_DEVICE_TABLE(usb, ir_id_table); static struct usb_serial_driver ir_device = { .driver = { .owner = THIS_MODULE, .name = "ir-usb", }, .description = "IR Dongle", .id_table = ir_id_table, .num_ports = 1, .set_termios = ir_set_termios, .attach = ir_startup, .open = ir_open, .prepare_write_buffer = ir_prepare_write_buffer, .process_read_urb = ir_process_read_urb, }; static struct usb_serial_driver * const serial_drivers[] = { &ir_device, NULL }; static inline void irda_usb_dump_class_desc(struct usb_serial *serial, struct usb_irda_cs_descriptor *desc) { struct device *dev = &serial->dev->dev; dev_dbg(dev, "bLength=%x\n", desc->bLength); dev_dbg(dev, "bDescriptorType=%x\n", desc->bDescriptorType); dev_dbg(dev, "bcdSpecRevision=%x\n", __le16_to_cpu(desc->bcdSpecRevision)); dev_dbg(dev, "bmDataSize=%x\n", desc->bmDataSize); dev_dbg(dev, "bmWindowSize=%x\n", desc->bmWindowSize); dev_dbg(dev, "bmMinTurnaroundTime=%d\n", desc->bmMinTurnaroundTime); dev_dbg(dev, "wBaudRate=%x\n", __le16_to_cpu(desc->wBaudRate)); dev_dbg(dev, "bmAdditionalBOFs=%x\n", desc->bmAdditionalBOFs); dev_dbg(dev, "bIrdaRateSniff=%x\n", desc->bIrdaRateSniff); dev_dbg(dev, "bMaxUnicastList=%x\n", desc->bMaxUnicastList); } /*------------------------------------------------------------------*/ /* * Function irda_usb_find_class_desc(dev, ifnum) * * Returns instance of IrDA class descriptor, or NULL if not found * * The class descriptor is some extra info that IrDA USB devices will * offer to us, describing their IrDA characteristics. We will use that in * irda_usb_init_qos() * * Based on the same function in drivers/net/irda/irda-usb.c */ static struct usb_irda_cs_descriptor * irda_usb_find_class_desc(struct usb_serial *serial, unsigned int ifnum) { struct usb_device *dev = serial->dev; struct usb_irda_cs_descriptor *desc; int ret; desc = kzalloc(sizeof(*desc), GFP_KERNEL); if (!desc) return NULL; ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), USB_REQ_CS_IRDA_GET_CLASS_DESC, USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0, ifnum, desc, sizeof(*desc), 1000); dev_dbg(&serial->dev->dev, "%s - ret=%d\n", __func__, ret); if (ret < (int)sizeof(*desc)) { dev_dbg(&serial->dev->dev, "%s - class descriptor read %s (%d)\n", __func__, (ret < 0) ? "failed" : "too short", ret); goto error; } if (desc->bDescriptorType != USB_DT_CS_IRDA) { dev_dbg(&serial->dev->dev, "%s - bad class descriptor type\n", __func__); goto error; } irda_usb_dump_class_desc(serial, desc); return desc; error: kfree(desc); return NULL; } static u8 ir_xbof_change(u8 xbof) { u8 result; /* reference irda-usb.c */ switch (xbof) { case 48: result = 0x10; break; case 28: case 24: result = 0x20; break; default: case 12: result = 0x30; break; case 5: case 6: result = 0x40; break; case 3: result = 0x50; break; case 2: result = 0x60; break; case 1: result = 0x70; break; case 0: result = 0x80; break; } return(result); } static int ir_startup(struct usb_serial *serial) { struct usb_irda_cs_descriptor *irda_desc; int rates; irda_desc = irda_usb_find_class_desc(serial, 0); if (!irda_desc) { dev_err(&serial->dev->dev, "IRDA class descriptor not found, device not bound\n"); return -ENODEV; } rates = le16_to_cpu(irda_desc->wBaudRate); dev_dbg(&serial->dev->dev, "%s - Baud rates supported:%s%s%s%s%s%s%s%s%s\n", __func__, (rates & USB_IRDA_BR_2400) ? " 2400" : "", (rates & USB_IRDA_BR_9600) ? " 9600" : "", (rates & USB_IRDA_BR_19200) ? " 19200" : "", (rates & USB_IRDA_BR_38400) ? " 38400" : "", (rates & USB_IRDA_BR_57600) ? " 57600" : "", (rates & USB_IRDA_BR_115200) ? " 115200" : "", (rates & USB_IRDA_BR_576000) ? " 576000" : "", (rates & USB_IRDA_BR_1152000) ? " 1152000" : "", (rates & USB_IRDA_BR_4000000) ? " 4000000" : ""); switch (irda_desc->bmAdditionalBOFs) { case USB_IRDA_AB_48: ir_add_bof = 48; break; case USB_IRDA_AB_24: ir_add_bof = 24; break; case USB_IRDA_AB_12: ir_add_bof = 12; break; case USB_IRDA_AB_6: ir_add_bof = 6; break; case USB_IRDA_AB_3: ir_add_bof = 3; break; case USB_IRDA_AB_2: ir_add_bof = 2; break; case USB_IRDA_AB_1: ir_add_bof = 1; break; case USB_IRDA_AB_0: ir_add_bof = 0; break; default: break; } kfree(irda_desc); return 0; } static int ir_open(struct tty_struct *tty, struct usb_serial_port *port) { int i; for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) port->write_urbs[i]->transfer_flags = URB_ZERO_PACKET; /* Start reading from the device */ return usb_serial_generic_open(tty, port); } static int ir_prepare_write_buffer(struct usb_serial_port *port, void *dest, size_t size) { unsigned char *buf = dest; int count; /* * The first byte of the packet we send to the device contains an * inbound header which indicates an additional number of BOFs and * a baud rate change. * * See section 5.4.2.2 of the USB IrDA spec. */ *buf = ir_xbof | ir_baud; count = kfifo_out_locked(&port->write_fifo, buf + 1, size - 1, &port->lock); return count + 1; } static void ir_process_read_urb(struct urb *urb) { struct usb_serial_port *port = urb->context; unsigned char *data = urb->transfer_buffer; if (!urb->actual_length) return; /* * The first byte of the packet we get from the device * contains a busy indicator and baud rate change. * See section 5.4.1.2 of the USB IrDA spec. */ if (*data & 0x0f) ir_baud = *data & 0x0f; if (urb->actual_length == 1) return; tty_insert_flip_string(&port->port, data + 1, urb->actual_length - 1); tty_flip_buffer_push(&port->port); } static void ir_set_termios_callback(struct urb *urb) { kfree(urb->transfer_buffer); if (urb->status) dev_dbg(&urb->dev->dev, "%s - non-zero urb status: %d\n", __func__, urb->status); } static void ir_set_termios(struct tty_struct *tty, struct usb_serial_port *port, struct ktermios *old_termios) { struct urb *urb; unsigned char *transfer_buffer; int result; speed_t baud; int ir_baud; baud = tty_get_baud_rate(tty); /* * FIXME, we should compare the baud request against the * capability stated in the IR header that we got in the * startup function. */ switch (baud) { case 2400: ir_baud = USB_IRDA_BR_2400; break; case 9600: ir_baud = USB_IRDA_BR_9600; break; case 19200: ir_baud = USB_IRDA_BR_19200; break; case 38400: ir_baud = USB_IRDA_BR_38400; break; case 57600: ir_baud = USB_IRDA_BR_57600; break; case 115200: ir_baud = USB_IRDA_BR_115200; break; case 576000: ir_baud = USB_IRDA_BR_576000; break; case 1152000: ir_baud = USB_IRDA_BR_1152000; break; case 4000000: ir_baud = USB_IRDA_BR_4000000; break; default: ir_baud = USB_IRDA_BR_9600; baud = 9600; } if (xbof == -1) ir_xbof = ir_xbof_change(ir_add_bof); else ir_xbof = ir_xbof_change(xbof) ; /* Only speed changes are supported */ tty_termios_copy_hw(&tty->termios, old_termios); tty_encode_baud_rate(tty, baud, baud); /* * send the baud change out on an "empty" data packet */ urb = usb_alloc_urb(0, GFP_KERNEL); if (!urb) return; transfer_buffer = kmalloc(1, GFP_KERNEL); if (!transfer_buffer) goto err_buf; *transfer_buffer = ir_xbof | ir_baud; usb_fill_bulk_urb( urb, port->serial->dev, usb_sndbulkpipe(port->serial->dev, port->bulk_out_endpointAddress), transfer_buffer, 1, ir_set_termios_callback, port); urb->transfer_flags = URB_ZERO_PACKET; result = usb_submit_urb(urb, GFP_KERNEL); if (result) { dev_err(&port->dev, "%s - failed to submit urb: %d\n", __func__, result); goto err_subm; } usb_free_urb(urb); return; err_subm: kfree(transfer_buffer); err_buf: usb_free_urb(urb); } static int __init ir_init(void) { if (buffer_size) { ir_device.bulk_in_size = buffer_size; ir_device.bulk_out_size = buffer_size; } return usb_serial_register_drivers(serial_drivers, KBUILD_MODNAME, ir_id_table); } static void __exit ir_exit(void) { usb_serial_deregister_drivers(serial_drivers); } module_init(ir_init); module_exit(ir_exit); MODULE_AUTHOR(DRIVER_AUTHOR); MODULE_DESCRIPTION(DRIVER_DESC); MODULE_LICENSE("GPL"); module_param(xbof, int, 0); MODULE_PARM_DESC(xbof, "Force specific number of XBOFs"); module_param(buffer_size, int, 0); MODULE_PARM_DESC(buffer_size, "Size of the transfer buffers");