diff options
Diffstat (limited to 'drivers/usb/serial/ir-usb.c')
| -rw-r--r-- | drivers/usb/serial/ir-usb.c | 488 |
1 files changed, 488 insertions, 0 deletions
diff --git a/drivers/usb/serial/ir-usb.c b/drivers/usb/serial/ir-usb.c new file mode 100644 index 000000000..82f108134 --- /dev/null +++ b/drivers/usb/serial/ir-usb.c @@ -0,0 +1,488 @@ +// 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 <weissg@vienna.at>, Dag Brattli + * <dag@brattli.net>, and Jean Tourrilhes <jt@hpl.hp.com> + * + * See Documentation/usb/usb-serial.rst for more information on using this + * driver + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/tty.h> +#include <linux/tty_driver.h> +#include <linux/tty_flip.h> +#include <linux/module.h> +#include <linux/spinlock.h> +#include <linux/uaccess.h> +#include <linux/usb.h> +#include <linux/usb/serial.h> +#include <linux/usb/irda.h> + +#define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Johan Hovold <jhovold@gmail.com>" +#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_write(struct tty_struct *tty, struct usb_serial_port *port, + const unsigned char *buf, int count); +static unsigned int ir_write_room(struct tty_struct *tty); +static void ir_write_bulk_callback(struct urb *urb); +static void ir_process_read_urb(struct urb *urb); +static void ir_set_termios(struct tty_struct *tty, + struct usb_serial_port *port, + const 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, + .num_bulk_in = 1, + .num_bulk_out = 1, + .set_termios = ir_set_termios, + .attach = ir_startup, + .write = ir_write, + .write_room = ir_write_room, + .write_bulk_callback = ir_write_bulk_callback, + .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_write(struct tty_struct *tty, struct usb_serial_port *port, + const unsigned char *buf, int count) +{ + struct urb *urb = NULL; + unsigned long flags; + int ret; + + if (port->bulk_out_size == 0) + return -EINVAL; + + if (count == 0) + return 0; + + count = min(count, port->bulk_out_size - 1); + + spin_lock_irqsave(&port->lock, flags); + if (__test_and_clear_bit(0, &port->write_urbs_free)) { + urb = port->write_urbs[0]; + port->tx_bytes += count; + } + spin_unlock_irqrestore(&port->lock, flags); + + if (!urb) + return 0; + + /* + * The first byte of the packet we send to the device contains an + * outbound header which indicates an additional number of BOFs and + * a baud rate change. + * + * See section 5.4.2.2 of the USB IrDA spec. + */ + *(u8 *)urb->transfer_buffer = ir_xbof | ir_baud; + + memcpy(urb->transfer_buffer + 1, buf, count); + + urb->transfer_buffer_length = count + 1; + urb->transfer_flags = URB_ZERO_PACKET; + + ret = usb_submit_urb(urb, GFP_ATOMIC); + if (ret) { + dev_err(&port->dev, "failed to submit write urb: %d\n", ret); + + spin_lock_irqsave(&port->lock, flags); + __set_bit(0, &port->write_urbs_free); + port->tx_bytes -= count; + spin_unlock_irqrestore(&port->lock, flags); + + return ret; + } + + return count; +} + +static void ir_write_bulk_callback(struct urb *urb) +{ + struct usb_serial_port *port = urb->context; + int status = urb->status; + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + __set_bit(0, &port->write_urbs_free); + port->tx_bytes -= urb->transfer_buffer_length - 1; + spin_unlock_irqrestore(&port->lock, flags); + + switch (status) { + case 0: + break; + case -ENOENT: + case -ECONNRESET: + case -ESHUTDOWN: + dev_dbg(&port->dev, "write urb stopped: %d\n", status); + return; + case -EPIPE: + dev_err(&port->dev, "write urb stopped: %d\n", status); + return; + default: + dev_err(&port->dev, "nonzero write-urb status: %d\n", status); + break; + } + + usb_serial_port_softint(port); +} + +static unsigned int ir_write_room(struct tty_struct *tty) +{ + struct usb_serial_port *port = tty->driver_data; + unsigned int count = 0; + + if (port->bulk_out_size == 0) + return 0; + + if (test_bit(0, &port->write_urbs_free)) + count = port->bulk_out_size - 1; + + return count; +} + +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(struct tty_struct *tty, + struct usb_serial_port *port, + const struct ktermios *old_termios) +{ + struct usb_device *udev = port->serial->dev; + unsigned char *transfer_buffer; + int actual_length; + speed_t baud; + int ir_baud; + int ret; + + 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_LS_2400; + break; + case 9600: + ir_baud = USB_IRDA_LS_9600; + break; + case 19200: + ir_baud = USB_IRDA_LS_19200; + break; + case 38400: + ir_baud = USB_IRDA_LS_38400; + break; + case 57600: + ir_baud = USB_IRDA_LS_57600; + break; + case 115200: + ir_baud = USB_IRDA_LS_115200; + break; + case 576000: + ir_baud = USB_IRDA_LS_576000; + break; + case 1152000: + ir_baud = USB_IRDA_LS_1152000; + break; + case 4000000: + ir_baud = USB_IRDA_LS_4000000; + break; + default: + ir_baud = USB_IRDA_LS_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 + */ + transfer_buffer = kmalloc(1, GFP_KERNEL); + if (!transfer_buffer) + return; + + *transfer_buffer = ir_xbof | ir_baud; + + ret = usb_bulk_msg(udev, + usb_sndbulkpipe(udev, port->bulk_out_endpointAddress), + transfer_buffer, 1, &actual_length, 5000); + if (ret || actual_length != 1) { + if (!ret) + ret = -EIO; + dev_err(&port->dev, "failed to change line speed: %d\n", ret); + } + + kfree(transfer_buffer); +} + +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"); + |