diff options
Diffstat (limited to 'drivers/usb/serial/keyspan_pda.c')
| -rw-r--r-- | drivers/usb/serial/keyspan_pda.c | 720 |
1 files changed, 720 insertions, 0 deletions
diff --git a/drivers/usb/serial/keyspan_pda.c b/drivers/usb/serial/keyspan_pda.c new file mode 100644 index 000000000..6fd15cd9e --- /dev/null +++ b/drivers/usb/serial/keyspan_pda.c @@ -0,0 +1,720 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * USB Keyspan PDA / Xircom / Entrega Converter driver + * + * Copyright (C) 1999 - 2001 Greg Kroah-Hartman <greg@kroah.com> + * Copyright (C) 1999, 2000 Brian Warner <warner@lothar.com> + * Copyright (C) 2000 Al Borchers <borchers@steinerpoint.com> + * Copyright (C) 2020 Johan Hovold <johan@kernel.org> + * + * See Documentation/usb/usb-serial.rst for more information on using this + * driver + */ + +#include <linux/kernel.h> +#include <linux/errno.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/workqueue.h> +#include <linux/uaccess.h> +#include <linux/usb.h> +#include <linux/usb/serial.h> +#include <linux/usb/ezusb.h> + +#define DRIVER_AUTHOR "Brian Warner <warner@lothar.com>, Johan Hovold <johan@kernel.org>" +#define DRIVER_DESC "USB Keyspan PDA Converter driver" + +#define KEYSPAN_TX_THRESHOLD 128 + +struct keyspan_pda_private { + int tx_room; + struct work_struct unthrottle_work; + struct usb_serial *serial; + struct usb_serial_port *port; +}; + +static int keyspan_pda_write_start(struct usb_serial_port *port); + +#define KEYSPAN_VENDOR_ID 0x06cd +#define KEYSPAN_PDA_FAKE_ID 0x0103 +#define KEYSPAN_PDA_ID 0x0104 /* no clue */ + +/* For Xircom PGSDB9 and older Entrega version of the same device */ +#define XIRCOM_VENDOR_ID 0x085a +#define XIRCOM_FAKE_ID 0x8027 +#define XIRCOM_FAKE_ID_2 0x8025 /* "PGMFHUB" serial */ +#define ENTREGA_VENDOR_ID 0x1645 +#define ENTREGA_FAKE_ID 0x8093 + +static const struct usb_device_id id_table_combined[] = { + { USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_FAKE_ID) }, + { USB_DEVICE(XIRCOM_VENDOR_ID, XIRCOM_FAKE_ID) }, + { USB_DEVICE(XIRCOM_VENDOR_ID, XIRCOM_FAKE_ID_2) }, + { USB_DEVICE(ENTREGA_VENDOR_ID, ENTREGA_FAKE_ID) }, + { USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_ID) }, + { } /* Terminating entry */ +}; +MODULE_DEVICE_TABLE(usb, id_table_combined); + +static const struct usb_device_id id_table_std[] = { + { USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_ID) }, + { } /* Terminating entry */ +}; + +static const struct usb_device_id id_table_fake[] = { + { USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_FAKE_ID) }, + { USB_DEVICE(XIRCOM_VENDOR_ID, XIRCOM_FAKE_ID) }, + { USB_DEVICE(XIRCOM_VENDOR_ID, XIRCOM_FAKE_ID_2) }, + { USB_DEVICE(ENTREGA_VENDOR_ID, ENTREGA_FAKE_ID) }, + { } /* Terminating entry */ +}; + +static int keyspan_pda_get_write_room(struct keyspan_pda_private *priv) +{ + struct usb_serial_port *port = priv->port; + struct usb_serial *serial = port->serial; + u8 room; + int rc; + + rc = usb_control_msg_recv(serial->dev, + 0, + 6, /* write_room */ + USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_IN, + 0, /* value: 0 means "remaining room" */ + 0, /* index */ + &room, + 1, + 2000, + GFP_KERNEL); + if (rc) { + dev_dbg(&port->dev, "roomquery failed: %d\n", rc); + return rc; + } + + dev_dbg(&port->dev, "roomquery says %d\n", room); + + return room; +} + +static void keyspan_pda_request_unthrottle(struct work_struct *work) +{ + struct keyspan_pda_private *priv = + container_of(work, struct keyspan_pda_private, unthrottle_work); + struct usb_serial_port *port = priv->port; + struct usb_serial *serial = port->serial; + unsigned long flags; + int result; + + dev_dbg(&port->dev, "%s\n", __func__); + + /* + * Ask the device to tell us when the tx buffer becomes + * sufficiently empty. + */ + result = usb_control_msg(serial->dev, + usb_sndctrlpipe(serial->dev, 0), + 7, /* request_unthrottle */ + USB_TYPE_VENDOR | USB_RECIP_INTERFACE + | USB_DIR_OUT, + KEYSPAN_TX_THRESHOLD, + 0, /* index */ + NULL, + 0, + 2000); + if (result < 0) + dev_dbg(&serial->dev->dev, "%s - error %d from usb_control_msg\n", + __func__, result); + /* + * Need to check available space after requesting notification in case + * buffer is already empty so that no notification is sent. + */ + result = keyspan_pda_get_write_room(priv); + if (result > KEYSPAN_TX_THRESHOLD) { + spin_lock_irqsave(&port->lock, flags); + priv->tx_room = max(priv->tx_room, result); + spin_unlock_irqrestore(&port->lock, flags); + + usb_serial_port_softint(port); + } +} + +static void keyspan_pda_rx_interrupt(struct urb *urb) +{ + struct usb_serial_port *port = urb->context; + unsigned char *data = urb->transfer_buffer; + unsigned int len = urb->actual_length; + int retval; + int status = urb->status; + struct keyspan_pda_private *priv; + unsigned long flags; + + priv = usb_get_serial_port_data(port); + + switch (status) { + case 0: + /* success */ + break; + case -ECONNRESET: + case -ENOENT: + case -ESHUTDOWN: + /* this urb is terminated, clean up */ + dev_dbg(&urb->dev->dev, "%s - urb shutting down with status: %d\n", __func__, status); + return; + default: + dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d\n", __func__, status); + goto exit; + } + + if (len < 1) { + dev_warn(&port->dev, "short message received\n"); + goto exit; + } + + /* see if the message is data or a status interrupt */ + switch (data[0]) { + case 0: + /* rest of message is rx data */ + if (len < 2) + break; + tty_insert_flip_string(&port->port, data + 1, len - 1); + tty_flip_buffer_push(&port->port); + break; + case 1: + /* status interrupt */ + if (len < 2) { + dev_warn(&port->dev, "short interrupt message received\n"); + break; + } + dev_dbg(&port->dev, "rx int, d1=%d\n", data[1]); + switch (data[1]) { + case 1: /* modemline change */ + break; + case 2: /* tx unthrottle interrupt */ + spin_lock_irqsave(&port->lock, flags); + priv->tx_room = max(priv->tx_room, KEYSPAN_TX_THRESHOLD); + spin_unlock_irqrestore(&port->lock, flags); + + keyspan_pda_write_start(port); + + usb_serial_port_softint(port); + break; + default: + break; + } + break; + default: + break; + } + +exit: + retval = usb_submit_urb(urb, GFP_ATOMIC); + if (retval) + dev_err(&port->dev, + "%s - usb_submit_urb failed with result %d\n", + __func__, retval); +} + +static void keyspan_pda_rx_throttle(struct tty_struct *tty) +{ + struct usb_serial_port *port = tty->driver_data; + + /* + * Stop receiving characters. We just turn off the URB request, and + * let chars pile up in the device. If we're doing hardware + * flowcontrol, the device will signal the other end when its buffer + * fills up. If we're doing XON/XOFF, this would be a good time to + * send an XOFF, although it might make sense to foist that off upon + * the device too. + */ + usb_kill_urb(port->interrupt_in_urb); +} + +static void keyspan_pda_rx_unthrottle(struct tty_struct *tty) +{ + struct usb_serial_port *port = tty->driver_data; + + /* just restart the receive interrupt URB */ + if (usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL)) + dev_dbg(&port->dev, "usb_submit_urb(read urb) failed\n"); +} + +static speed_t keyspan_pda_setbaud(struct usb_serial *serial, speed_t baud) +{ + int rc; + int bindex; + + switch (baud) { + case 110: + bindex = 0; + break; + case 300: + bindex = 1; + break; + case 1200: + bindex = 2; + break; + case 2400: + bindex = 3; + break; + case 4800: + bindex = 4; + break; + case 9600: + bindex = 5; + break; + case 19200: + bindex = 6; + break; + case 38400: + bindex = 7; + break; + case 57600: + bindex = 8; + break; + case 115200: + bindex = 9; + break; + default: + bindex = 5; /* Default to 9600 */ + baud = 9600; + } + + rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), + 0, /* set baud */ + USB_TYPE_VENDOR + | USB_RECIP_INTERFACE + | USB_DIR_OUT, /* type */ + bindex, /* value */ + 0, /* index */ + NULL, /* &data */ + 0, /* size */ + 2000); /* timeout */ + if (rc < 0) + return 0; + + return baud; +} + +static void keyspan_pda_break_ctl(struct tty_struct *tty, int break_state) +{ + struct usb_serial_port *port = tty->driver_data; + struct usb_serial *serial = port->serial; + int value; + int result; + + if (break_state == -1) + value = 1; /* start break */ + else + value = 0; /* clear break */ + + result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), + 4, /* set break */ + USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT, + value, 0, NULL, 0, 2000); + if (result < 0) + dev_dbg(&port->dev, "%s - error %d from usb_control_msg\n", + __func__, result); +} + +static void keyspan_pda_set_termios(struct tty_struct *tty, + struct usb_serial_port *port, + const struct ktermios *old_termios) +{ + struct usb_serial *serial = port->serial; + speed_t speed; + + /* + * cflag specifies lots of stuff: number of stop bits, parity, number + * of data bits, baud. What can the device actually handle?: + * CSTOPB (1 stop bit or 2) + * PARENB (parity) + * CSIZE (5bit .. 8bit) + * There is minimal hw support for parity (a PSW bit seems to hold the + * parity of whatever is in the accumulator). The UART either deals + * with 10 bits (start, 8 data, stop) or 11 bits (start, 8 data, + * 1 special, stop). So, with firmware changes, we could do: + * 8N1: 10 bit + * 8N2: 11 bit, extra bit always (mark?) + * 8[EOMS]1: 11 bit, extra bit is parity + * 7[EOMS]1: 10 bit, b0/b7 is parity + * 7[EOMS]2: 11 bit, b0/b7 is parity, extra bit always (mark?) + * + * HW flow control is dictated by the tty->termios.c_cflags & CRTSCTS + * bit. + * + * For now, just do baud. + */ + speed = tty_get_baud_rate(tty); + speed = keyspan_pda_setbaud(serial, speed); + + if (speed == 0) { + dev_dbg(&port->dev, "can't handle requested baud rate\n"); + /* It hasn't changed so.. */ + speed = tty_termios_baud_rate(old_termios); + } + /* + * Only speed can change so copy the old h/w parameters then encode + * the new speed. + */ + tty_termios_copy_hw(&tty->termios, old_termios); + tty_encode_baud_rate(tty, speed, speed); +} + +/* + * Modem control pins: DTR and RTS are outputs and can be controlled. + * DCD, RI, DSR, CTS are inputs and can be read. All outputs can also be + * read. The byte passed is: DTR(b7) DCD RI DSR CTS RTS(b2) unused unused. + */ +static int keyspan_pda_get_modem_info(struct usb_serial *serial, + unsigned char *value) +{ + int rc; + u8 data; + + rc = usb_control_msg_recv(serial->dev, 0, + 3, /* get pins */ + USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_IN, + 0, + 0, + &data, + 1, + 2000, + GFP_KERNEL); + if (rc == 0) + *value = data; + + return rc; +} + +static int keyspan_pda_set_modem_info(struct usb_serial *serial, + unsigned char value) +{ + int rc; + rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), + 3, /* set pins */ + USB_TYPE_VENDOR|USB_RECIP_INTERFACE|USB_DIR_OUT, + value, 0, NULL, 0, 2000); + return rc; +} + +static int keyspan_pda_tiocmget(struct tty_struct *tty) +{ + struct usb_serial_port *port = tty->driver_data; + struct usb_serial *serial = port->serial; + int rc; + unsigned char status; + int value; + + rc = keyspan_pda_get_modem_info(serial, &status); + if (rc < 0) + return rc; + + value = ((status & BIT(7)) ? TIOCM_DTR : 0) | + ((status & BIT(6)) ? TIOCM_CAR : 0) | + ((status & BIT(5)) ? TIOCM_RNG : 0) | + ((status & BIT(4)) ? TIOCM_DSR : 0) | + ((status & BIT(3)) ? TIOCM_CTS : 0) | + ((status & BIT(2)) ? TIOCM_RTS : 0); + + return value; +} + +static int keyspan_pda_tiocmset(struct tty_struct *tty, + unsigned int set, unsigned int clear) +{ + struct usb_serial_port *port = tty->driver_data; + struct usb_serial *serial = port->serial; + int rc; + unsigned char status; + + rc = keyspan_pda_get_modem_info(serial, &status); + if (rc < 0) + return rc; + + if (set & TIOCM_RTS) + status |= BIT(2); + if (set & TIOCM_DTR) + status |= BIT(7); + + if (clear & TIOCM_RTS) + status &= ~BIT(2); + if (clear & TIOCM_DTR) + status &= ~BIT(7); + rc = keyspan_pda_set_modem_info(serial, status); + return rc; +} + +static int keyspan_pda_write_start(struct usb_serial_port *port) +{ + struct keyspan_pda_private *priv = usb_get_serial_port_data(port); + unsigned long flags; + struct urb *urb; + int count; + int room; + int rc; + + /* + * Guess how much room is left in the device's ring buffer. If our + * write will result in no room left, ask the device to give us an + * interrupt when the room available rises above a threshold but also + * query how much room is currently available (in case our guess was + * too conservative and the buffer is already empty when the + * unthrottle work is scheduled). + */ + + /* + * We might block because of: + * the TX urb is in-flight (wait until it completes) + * the device is full (wait until it says there is room) + */ + spin_lock_irqsave(&port->lock, flags); + + room = priv->tx_room; + count = kfifo_len(&port->write_fifo); + + if (!test_bit(0, &port->write_urbs_free) || count == 0 || room == 0) { + spin_unlock_irqrestore(&port->lock, flags); + return 0; + } + __clear_bit(0, &port->write_urbs_free); + + if (count > room) + count = room; + if (count > port->bulk_out_size) + count = port->bulk_out_size; + + urb = port->write_urb; + count = kfifo_out(&port->write_fifo, urb->transfer_buffer, count); + urb->transfer_buffer_length = count; + + port->tx_bytes += count; + priv->tx_room -= count; + + spin_unlock_irqrestore(&port->lock, flags); + + dev_dbg(&port->dev, "%s - count = %d, txroom = %d\n", __func__, count, room); + + rc = usb_submit_urb(urb, GFP_ATOMIC); + if (rc) { + dev_dbg(&port->dev, "usb_submit_urb(write bulk) failed\n"); + + spin_lock_irqsave(&port->lock, flags); + port->tx_bytes -= count; + priv->tx_room = max(priv->tx_room, room + count); + __set_bit(0, &port->write_urbs_free); + spin_unlock_irqrestore(&port->lock, flags); + + return rc; + } + + if (count == room) + schedule_work(&priv->unthrottle_work); + + return count; +} + +static void keyspan_pda_write_bulk_callback(struct urb *urb) +{ + struct usb_serial_port *port = urb->context; + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + port->tx_bytes -= urb->transfer_buffer_length; + __set_bit(0, &port->write_urbs_free); + spin_unlock_irqrestore(&port->lock, flags); + + keyspan_pda_write_start(port); + + usb_serial_port_softint(port); +} + +static int keyspan_pda_write(struct tty_struct *tty, struct usb_serial_port *port, + const unsigned char *buf, int count) +{ + int rc; + + dev_dbg(&port->dev, "%s - count = %d\n", __func__, count); + + if (!count) + return 0; + + count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock); + + rc = keyspan_pda_write_start(port); + if (rc) + return rc; + + return count; +} + +static void keyspan_pda_dtr_rts(struct usb_serial_port *port, int on) +{ + struct usb_serial *serial = port->serial; + + if (on) + keyspan_pda_set_modem_info(serial, BIT(7) | BIT(2)); + else + keyspan_pda_set_modem_info(serial, 0); +} + + +static int keyspan_pda_open(struct tty_struct *tty, + struct usb_serial_port *port) +{ + struct keyspan_pda_private *priv = usb_get_serial_port_data(port); + int rc; + + /* find out how much room is in the Tx ring */ + rc = keyspan_pda_get_write_room(priv); + if (rc < 0) + return rc; + + spin_lock_irq(&port->lock); + priv->tx_room = rc; + spin_unlock_irq(&port->lock); + + rc = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL); + if (rc) { + dev_dbg(&port->dev, "%s - usb_submit_urb(read int) failed\n", __func__); + return rc; + } + + return 0; +} + +static void keyspan_pda_close(struct usb_serial_port *port) +{ + struct keyspan_pda_private *priv = usb_get_serial_port_data(port); + + /* + * Stop the interrupt URB first as its completion handler may submit + * the write URB. + */ + usb_kill_urb(port->interrupt_in_urb); + usb_kill_urb(port->write_urb); + + cancel_work_sync(&priv->unthrottle_work); + + spin_lock_irq(&port->lock); + kfifo_reset(&port->write_fifo); + spin_unlock_irq(&port->lock); +} + +/* download the firmware to a "fake" device (pre-renumeration) */ +static int keyspan_pda_fake_startup(struct usb_serial *serial) +{ + unsigned int vid = le16_to_cpu(serial->dev->descriptor.idVendor); + const char *fw_name; + + /* download the firmware here ... */ + ezusb_fx1_set_reset(serial->dev, 1); + + switch (vid) { + case KEYSPAN_VENDOR_ID: + fw_name = "keyspan_pda/keyspan_pda.fw"; + break; + case XIRCOM_VENDOR_ID: + case ENTREGA_VENDOR_ID: + fw_name = "keyspan_pda/xircom_pgs.fw"; + break; + default: + dev_err(&serial->dev->dev, "%s: unknown vendor, aborting.\n", + __func__); + return -ENODEV; + } + + if (ezusb_fx1_ihex_firmware_download(serial->dev, fw_name) < 0) { + dev_err(&serial->dev->dev, "failed to load firmware \"%s\"\n", + fw_name); + return -ENOENT; + } + + /* + * After downloading firmware renumeration will occur in a moment and + * the new device will bind to the real driver. + */ + + /* We want this device to fail to have a driver assigned to it. */ + return 1; +} + +MODULE_FIRMWARE("keyspan_pda/keyspan_pda.fw"); +MODULE_FIRMWARE("keyspan_pda/xircom_pgs.fw"); + +static int keyspan_pda_port_probe(struct usb_serial_port *port) +{ + + struct keyspan_pda_private *priv; + + priv = kmalloc(sizeof(struct keyspan_pda_private), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + INIT_WORK(&priv->unthrottle_work, keyspan_pda_request_unthrottle); + priv->port = port; + + usb_set_serial_port_data(port, priv); + + return 0; +} + +static void keyspan_pda_port_remove(struct usb_serial_port *port) +{ + struct keyspan_pda_private *priv; + + priv = usb_get_serial_port_data(port); + kfree(priv); +} + +static struct usb_serial_driver keyspan_pda_fake_device = { + .driver = { + .owner = THIS_MODULE, + .name = "keyspan_pda_pre", + }, + .description = "Keyspan PDA - (prerenumeration)", + .id_table = id_table_fake, + .num_ports = 1, + .attach = keyspan_pda_fake_startup, +}; + +static struct usb_serial_driver keyspan_pda_device = { + .driver = { + .owner = THIS_MODULE, + .name = "keyspan_pda", + }, + .description = "Keyspan PDA", + .id_table = id_table_std, + .num_ports = 1, + .num_bulk_out = 1, + .num_interrupt_in = 1, + .dtr_rts = keyspan_pda_dtr_rts, + .open = keyspan_pda_open, + .close = keyspan_pda_close, + .write = keyspan_pda_write, + .write_bulk_callback = keyspan_pda_write_bulk_callback, + .read_int_callback = keyspan_pda_rx_interrupt, + .throttle = keyspan_pda_rx_throttle, + .unthrottle = keyspan_pda_rx_unthrottle, + .set_termios = keyspan_pda_set_termios, + .break_ctl = keyspan_pda_break_ctl, + .tiocmget = keyspan_pda_tiocmget, + .tiocmset = keyspan_pda_tiocmset, + .port_probe = keyspan_pda_port_probe, + .port_remove = keyspan_pda_port_remove, +}; + +static struct usb_serial_driver * const serial_drivers[] = { + &keyspan_pda_device, + &keyspan_pda_fake_device, + NULL +}; + +module_usb_serial_driver(serial_drivers, id_table_combined); + +MODULE_AUTHOR(DRIVER_AUTHOR); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); |