/* * USB Serial Converter Generic functions * * Copyright (C) 1999 - 2002 Greg Kroah-Hartman (greg@kroah.com) * * 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/errno.h> #include <linux/slab.h> #include <linux/tty.h> #include <linux/tty_flip.h> #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/usb.h> #include <linux/usb/serial.h> #include <linux/uaccess.h> static int debug; #ifdef CONFIG_USB_SERIAL_GENERIC static int generic_probe(struct usb_interface *interface, const struct usb_device_id *id); static __u16 vendor = 0x05f9; static __u16 product = 0xffff; module_param(vendor, ushort, 0); MODULE_PARM_DESC(vendor, "User specified USB idVendor"); module_param(product, ushort, 0); MODULE_PARM_DESC(product, "User specified USB idProduct"); static struct usb_device_id generic_device_ids[2]; /* Initially all zeroes. */ /* we want to look at all devices, as the vendor/product id can change * depending on the command line argument */ static struct usb_device_id generic_serial_ids[] = { {.driver_info = 42}, {} }; static struct usb_driver generic_driver = { .name = "usbserial_generic", .probe = generic_probe, .disconnect = usb_serial_disconnect, .id_table = generic_serial_ids, .no_dynamic_id = 1, }; /* All of the device info needed for the Generic Serial Converter */ struct usb_serial_driver usb_serial_generic_device = { .driver = { .owner = THIS_MODULE, .name = "generic", }, .id_table = generic_device_ids, .usb_driver = &generic_driver, .num_ports = 1, .shutdown = usb_serial_generic_shutdown, .throttle = usb_serial_generic_throttle, .unthrottle = usb_serial_generic_unthrottle, .resume = usb_serial_generic_resume, }; static int generic_probe(struct usb_interface *interface, const struct usb_device_id *id) { const struct usb_device_id *id_pattern; id_pattern = usb_match_id(interface, generic_device_ids); if (id_pattern != NULL) return usb_serial_probe(interface, id); return -ENODEV; } #endif int usb_serial_generic_register(int _debug) { int retval = 0; debug = _debug; #ifdef CONFIG_USB_SERIAL_GENERIC generic_device_ids[0].idVendor = vendor; generic_device_ids[0].idProduct = product; generic_device_ids[0].match_flags = USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_PRODUCT; /* register our generic driver with ourselves */ retval = usb_serial_register(&usb_serial_generic_device); if (retval) goto exit; retval = usb_register(&generic_driver); if (retval) usb_serial_deregister(&usb_serial_generic_device); exit: #endif return retval; } void usb_serial_generic_deregister(void) { #ifdef CONFIG_USB_SERIAL_GENERIC /* remove our generic driver */ usb_deregister(&generic_driver); usb_serial_deregister(&usb_serial_generic_device); #endif } int usb_serial_generic_open(struct tty_struct *tty, struct usb_serial_port *port, struct file *filp) { struct usb_serial *serial = port->serial; int result = 0; unsigned long flags; dbg("%s - port %d", __func__, port->number); /* force low_latency on so that our tty_push actually forces the data through, otherwise it is scheduled, and with high data rates (like with OHCI) data can get lost. */ if (tty) tty->low_latency = 1; /* clear the throttle flags */ spin_lock_irqsave(&port->lock, flags); port->throttled = 0; port->throttle_req = 0; spin_unlock_irqrestore(&port->lock, flags); /* if we have a bulk endpoint, start reading from it */ if (serial->num_bulk_in) { /* Start reading from the device */ usb_fill_bulk_urb(port->read_urb, serial->dev, usb_rcvbulkpipe(serial->dev, port->bulk_in_endpointAddress), port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length, ((serial->type->read_bulk_callback) ? serial->type->read_bulk_callback : usb_serial_generic_read_bulk_callback), port); result = usb_submit_urb(port->read_urb, GFP_KERNEL); if (result) dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __func__, result); } return result; } EXPORT_SYMBOL_GPL(usb_serial_generic_open); static void generic_cleanup(struct usb_serial_port *port) { struct usb_serial *serial = port->serial; dbg("%s - port %d", __func__, port->number); if (serial->dev) { /* shutdown any bulk reads that might be going on */ if (serial->num_bulk_out) usb_kill_urb(port->write_urb); if (serial->num_bulk_in) usb_kill_urb(port->read_urb); } } int usb_serial_generic_resume(struct usb_serial *serial) { struct usb_serial_port *port; int i, c = 0, r; for (i = 0; i < serial->num_ports; i++) { port = serial->port[i]; if (port->port.count && port->read_urb) { r = usb_submit_urb(port->read_urb, GFP_NOIO); if (r < 0) c++; } } return c ? -EIO : 0; } EXPORT_SYMBOL_GPL(usb_serial_generic_resume); void usb_serial_generic_close(struct tty_struct *tty, struct usb_serial_port *port, struct file *filp) { dbg("%s - port %d", __func__, port->number); generic_cleanup(port); } int usb_serial_generic_write(struct tty_struct *tty, struct usb_serial_port *port, const unsigned char *buf, int count) { struct usb_serial *serial = port->serial; int result; unsigned char *data; dbg("%s - port %d", __func__, port->number); if (count == 0) { dbg("%s - write request of 0 bytes", __func__); return 0; } /* only do something if we have a bulk out endpoint */ if (serial->num_bulk_out) { unsigned long flags; spin_lock_irqsave(&port->lock, flags); if (port->write_urb_busy) { spin_unlock_irqrestore(&port->lock, flags); dbg("%s - already writing", __func__); return 0; } port->write_urb_busy = 1; spin_unlock_irqrestore(&port->lock, flags); count = (count > port->bulk_out_size) ? port->bulk_out_size : count; memcpy(port->write_urb->transfer_buffer, buf, count); data = port->write_urb->transfer_buffer; usb_serial_debug_data(debug, &port->dev, __func__, count, data); /* set up our urb */ usb_fill_bulk_urb(port->write_urb, serial->dev, usb_sndbulkpipe(serial->dev, port->bulk_out_endpointAddress), port->write_urb->transfer_buffer, count, ((serial->type->write_bulk_callback) ? serial->type->write_bulk_callback : usb_serial_generic_write_bulk_callback), port); /* send the data out the bulk port */ port->write_urb_busy = 1; result = usb_submit_urb(port->write_urb, GFP_ATOMIC); if (result) { dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __func__, result); /* don't have to grab the lock here, as we will retry if != 0 */ port->write_urb_busy = 0; } else result = count; return result; } /* no bulk out, so return 0 bytes written */ return 0; } int usb_serial_generic_write_room(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; struct usb_serial *serial = port->serial; int room = 0; dbg("%s - port %d", __func__, port->number); /* FIXME: Locking */ if (serial->num_bulk_out) { if (!(port->write_urb_busy)) room = port->bulk_out_size; } dbg("%s - returns %d", __func__, room); return room; } int usb_serial_generic_chars_in_buffer(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; struct usb_serial *serial = port->serial; int chars = 0; dbg("%s - port %d", __func__, port->number); /* FIXME: Locking */ if (serial->num_bulk_out) { if (port->write_urb_busy) chars = port->write_urb->transfer_buffer_length; } dbg("%s - returns %d", __func__, chars); return chars; } static void resubmit_read_urb(struct usb_serial_port *port, gfp_t mem_flags) { struct urb *urb = port->read_urb; struct usb_serial *serial = port->serial; int result; /* Continue reading from device */ usb_fill_bulk_urb(urb, serial->dev, usb_rcvbulkpipe(serial->dev, port->bulk_in_endpointAddress), urb->transfer_buffer, urb->transfer_buffer_length, ((serial->type->read_bulk_callback) ? serial->type->read_bulk_callback : usb_serial_generic_read_bulk_callback), port); result = usb_submit_urb(urb, mem_flags); if (result) dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __func__, result); } /* Push data to tty layer and resubmit the bulk read URB */ static void flush_and_resubmit_read_urb(struct usb_serial_port *port) { struct urb *urb = port->read_urb; struct tty_struct *tty = tty_port_tty_get(&port->port); int room; /* Push data to tty */ if (tty && urb->actual_length) { room = tty_buffer_request_room(tty, urb->actual_length); if (room) { tty_insert_flip_string(tty, urb->transfer_buffer, room); tty_flip_buffer_push(tty); } } tty_kref_put(tty); resubmit_read_urb(port, GFP_ATOMIC); } void usb_serial_generic_read_bulk_callback(struct urb *urb) { struct usb_serial_port *port = urb->context; unsigned char *data = urb->transfer_buffer; int status = urb->status; unsigned long flags; dbg("%s - port %d", __func__, port->number); if (unlikely(status != 0)) { dbg("%s - nonzero read bulk status received: %d", __func__, status); return; } usb_serial_debug_data(debug, &port->dev, __func__, urb->actual_length, data); /* Throttle the device if requested by tty */ spin_lock_irqsave(&port->lock, flags); port->throttled = port->throttle_req; if (!port->throttled) { spin_unlock_irqrestore(&port->lock, flags); flush_and_resubmit_read_urb(port); } else spin_unlock_irqrestore(&port->lock, flags); } EXPORT_SYMBOL_GPL(usb_serial_generic_read_bulk_callback); void usb_serial_generic_write_bulk_callback(struct urb *urb) { struct usb_serial_port *port = urb->context; int status = urb->status; dbg("%s - port %d", __func__, port->number); port->write_urb_busy = 0; if (status) { dbg("%s - nonzero write bulk status received: %d", __func__, status); return; } usb_serial_port_softint(port); } EXPORT_SYMBOL_GPL(usb_serial_generic_write_bulk_callback); void usb_serial_generic_throttle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; unsigned long flags; dbg("%s - port %d", __func__, port->number); /* Set the throttle request flag. It will be picked up * by usb_serial_generic_read_bulk_callback(). */ spin_lock_irqsave(&port->lock, flags); port->throttle_req = 1; spin_unlock_irqrestore(&port->lock, flags); } void usb_serial_generic_unthrottle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; int was_throttled; unsigned long flags; dbg("%s - port %d", __func__, port->number); /* Clear the throttle flags */ spin_lock_irqsave(&port->lock, flags); was_throttled = port->throttled; port->throttled = port->throttle_req = 0; spin_unlock_irqrestore(&port->lock, flags); if (was_throttled) { /* Resume reading from device */ resubmit_read_urb(port, GFP_KERNEL); } } void usb_serial_generic_shutdown(struct usb_serial *serial) { int i; dbg("%s", __func__); /* stop reads and writes on all ports */ for (i = 0; i < serial->num_ports; ++i) generic_cleanup(serial->port[i]); }