linuxdebug/drivers/usb/serial/keyspan_pda.c

721 lines
18 KiB
C
Raw Permalink Normal View History

2024-07-16 15:50:57 +02:00
// 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");