shmem: new export ops

[linux-2.6/linux-trees-mm.git] / drivers / usb / serial / ipw.c

/*
 * IPWireless 3G UMTS TDD Modem driver (USB connected)
 *
 *   Copyright (C) 2004 Roelf Diedericks <roelfd@inet.co.za>
 *   Copyright (C) 2004 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 as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 * All information about the device was acquired using SnoopyPro
 * on MSFT's O/S, and examing the MSFT drivers' debug output 
 * (insanely left _on_ in the enduser version)
 *
 * It was written out of frustration with the IPWireless USB modem
 * supplied by Axity3G/Sentech South Africa not supporting
 * Linux whatsoever.
 *
 * Nobody provided any proprietary information that was not already 
 * available for this device.
 * 
 * The modem adheres to the "3GPP TS  27.007 AT command set for 3G 
 * User Equipment (UE)" standard, available from 
 * http://www.3gpp.org/ftp/Specs/html-info/27007.htm
 *
 * The code was only tested the IPWireless handheld modem distributed
 * in South Africa by Sentech.
 * 
 * It may work for Woosh Inc in .nz too, as it appears they use the
 * same kit.
 *
 * There is still some work to be done in terms of handling 
 * DCD, DTR, RTS, CTS which are currently faked.
 * It's good enough for PPP at this point. It's based off all kinds of
 * code found in usb/serial and usb/class
 *
 */

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include <asm/uaccess.h>

/*
 * Version Information
 */
#define DRIVER_VERSION  "v0.3"
#define DRIVER_AUTHOR   "Roelf Diedericks"
#define DRIVER_DESC     "IPWireless tty driver"

#define IPW_TTY_MAJOR   240     /* real device node major id, experimental range */
#define IPW_TTY_MINORS  256     /* we support 256 devices, dunno why, it'd be insane :) */

#define USB_IPW_MAGIC   0x6d02  /* magic number for ipw struct */


/* Message sizes */
#define EVENT_BUFFER_SIZE       0xFF
#define CHAR2INT16(c1,c0)       (((u32)((c1) & 0xff) << 8) + (u32)((c0) & 0xff))
#define NUM_BULK_URBS           24
#define NUM_CONTROL_URBS        16

/* vendor/product pairs that are known work with this driver*/
#define IPW_VID         0x0bc3
#define IPW_PID         0x0001


/* Vendor commands: */

/* baud rates */
enum {
        ipw_sio_b256000 = 0x000e,
        ipw_sio_b128000 = 0x001d,
        ipw_sio_b115200 = 0x0020,
        ipw_sio_b57600  = 0x0040,
        ipw_sio_b56000  = 0x0042,
        ipw_sio_b38400  = 0x0060,
        ipw_sio_b19200  = 0x00c0,
        ipw_sio_b14400  = 0x0100,
        ipw_sio_b9600   = 0x0180,
        ipw_sio_b4800   = 0x0300,
        ipw_sio_b2400   = 0x0600,
        ipw_sio_b1200   = 0x0c00,
        ipw_sio_b600    = 0x1800
};

/* data bits */
#define ipw_dtb_7               0x700
#define ipw_dtb_8               0x810   // ok so the define is misleading, I know, but forces 8,n,1
                                        // I mean, is there a point to any other setting these days? :) 

/* usb control request types : */
#define IPW_SIO_RXCTL           0x00    // control bulk rx channel transmissions, value=1/0 (on/off)
#define IPW_SIO_SET_BAUD        0x01    // set baud, value=requested ipw_sio_bxxxx
#define IPW_SIO_SET_LINE        0x03    // set databits, parity. value=ipw_dtb_x
#define IPW_SIO_SET_PIN         0x03    // set/clear dtr/rts value=ipw_pin_xxx
#define IPW_SIO_POLL            0x08    // get serial port status byte, call with value=0
#define IPW_SIO_INIT            0x11    // initializes ? value=0 (appears as first thing todo on open)
#define IPW_SIO_PURGE           0x12    // purge all transmissions?, call with value=numchar_to_purge
#define IPW_SIO_HANDFLOW        0x13    // set xon/xoff limits value=0, and a buffer of 0x10 bytes
#define IPW_SIO_SETCHARS        0x13    // set the flowcontrol special chars, value=0, buf=6 bytes, 
                                        // last 2 bytes contain flowcontrol chars e.g. 00 00 00 00 11 13

/* values used for request IPW_SIO_SET_PIN */
#define IPW_PIN_SETDTR          0x101
#define IPW_PIN_SETRTS          0x202
#define IPW_PIN_CLRDTR          0x100
#define IPW_PIN_CLRRTS          0x200 // unconfirmed

/* values used for request IPW_SIO_RXCTL */
#define IPW_RXBULK_ON           1
#define IPW_RXBULK_OFF          0

/* various 16 byte hardcoded transferbuffers used by flow control */
#define IPW_BYTES_FLOWINIT      { 0x01, 0, 0, 0, 0x40, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }

/* Interpretation of modem status lines */
/* These need sorting out by individually connecting pins and checking
 * results. FIXME!
 * When data is being sent we see 0x30 in the lower byte; this must
 * contain DSR and CTS ...
 */
#define IPW_DSR                 ((1<<4) | (1<<5))
#define IPW_CTS                 ((1<<5) | (1<<4))

#define IPW_WANTS_TO_SEND       0x30
//#define IPW_DTR                       /* Data Terminal Ready */
//#define IPW_CTS                       /* Clear To Send */
//#define IPW_CD                        /* Carrier Detect */
//#define IPW_DSR                       /* Data Set Ready */
//#define IPW_RxD                       /* Receive pin */

//#define IPW_LE
//#define IPW_RTS               
//#define IPW_ST                
//#define IPW_SR                
//#define IPW_RI                        /* Ring Indicator */

static struct usb_device_id usb_ipw_ids[] = {
        { USB_DEVICE(IPW_VID, IPW_PID) },
        { },
};

MODULE_DEVICE_TABLE(usb, usb_ipw_ids);

static struct usb_driver usb_ipw_driver = {
        .name =         "ipwtty",
        .probe =        usb_serial_probe,
        .disconnect =   usb_serial_disconnect,
        .id_table =     usb_ipw_ids,
        .no_dynamic_id =        1,
};

static int debug;

static void ipw_read_bulk_callback(struct urb *urb)
{
        struct usb_serial_port *port = urb->context;
        unsigned char *data = urb->transfer_buffer;
        struct tty_struct *tty;
        int result;
        int status = urb->status;

        dbg("%s - port %d", __FUNCTION__, port->number);

        if (status) {
                dbg("%s - nonzero read bulk status received: %d",
                    __FUNCTION__, status);
                return;
        }

        usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);

        tty = port->tty;
        if (tty && urb->actual_length) {
                tty_buffer_request_room(tty, urb->actual_length);
                tty_insert_flip_string(tty, data, urb->actual_length);
                tty_flip_buffer_push(tty);
        }

        /* Continue trying to always read  */
        usb_fill_bulk_urb (port->read_urb, port->serial->dev,
                           usb_rcvbulkpipe(port->serial->dev,
                                           port->bulk_in_endpointAddress),
                           port->read_urb->transfer_buffer,
                           port->read_urb->transfer_buffer_length,
                           ipw_read_bulk_callback, port);
        result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
        if (result)
                dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
        return;
}

static int ipw_open(struct usb_serial_port *port, struct file *filp)
{
        struct usb_device *dev = port->serial->dev;
        u8 buf_flow_static[16] = IPW_BYTES_FLOWINIT;
        u8 *buf_flow_init;
        int result;

        dbg("%s", __FUNCTION__);

        buf_flow_init = kmemdup(buf_flow_static, 16, GFP_KERNEL);
        if (!buf_flow_init)
                return -ENOMEM;

        if (port->tty)
                port->tty->low_latency = 1;

        /* --1: Tell the modem to initialize (we think) From sniffs this is always the
         * first thing that gets sent to the modem during opening of the device */
        dbg("%s: Sending SIO_INIT (we guess)",__FUNCTION__);
        result = usb_control_msg(dev, usb_sndctrlpipe(dev,0),
                                 IPW_SIO_INIT,
                                 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
                                 0,
                                 0, /* index */
                                 NULL,
                                 0,
                                 100000);
        if (result < 0)
                dev_err(&port->dev, "Init of modem failed (error = %d)\n", result);

        /* reset the bulk pipes */
        usb_clear_halt(dev, usb_rcvbulkpipe(dev, port->bulk_in_endpointAddress));
        usb_clear_halt(dev, usb_sndbulkpipe(dev, port->bulk_out_endpointAddress));

        /*--2: Start reading from the device */ 
        dbg("%s: setting up bulk read callback",__FUNCTION__);
        usb_fill_bulk_urb(port->read_urb, dev,
                          usb_rcvbulkpipe(dev, port->bulk_in_endpointAddress),
                          port->bulk_in_buffer,
                          port->bulk_in_size,
                          ipw_read_bulk_callback, port);
        result = usb_submit_urb(port->read_urb, GFP_KERNEL);
        if (result < 0)
                dbg("%s - usb_submit_urb(read bulk) failed with status %d", __FUNCTION__, result);

        /*--3: Tell the modem to open the floodgates on the rx bulk channel */
        dbg("%s:asking modem for RxRead (RXBULK_ON)",__FUNCTION__);
        result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
                                 IPW_SIO_RXCTL,
                                 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
                                 IPW_RXBULK_ON,
                                 0, /* index */
                                 NULL,
                                 0,
                                 100000);
        if (result < 0) 
                dev_err(&port->dev, "Enabling bulk RxRead failed (error = %d)\n", result);

        /*--4: setup the initial flowcontrol */
        dbg("%s:setting init flowcontrol (%s)",__FUNCTION__,buf_flow_init);
        result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
                                 IPW_SIO_HANDFLOW,
                                 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
                                 0,
                                 0,
                                 buf_flow_init,
                                 0x10,
                                 200000);
        if (result < 0)
                dev_err(&port->dev, "initial flowcontrol failed (error = %d)\n", result);


        /*--5: raise the dtr */
        dbg("%s:raising dtr",__FUNCTION__);
        result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
                                 IPW_SIO_SET_PIN,
                                 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
                                 IPW_PIN_SETDTR,
                                 0,
                                 NULL,
                                 0,
                                 200000);
        if (result < 0)
                dev_err(&port->dev, "setting dtr failed (error = %d)\n", result);

        /*--6: raise the rts */
        dbg("%s:raising rts",__FUNCTION__);
        result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
                                 IPW_SIO_SET_PIN,
                                 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
                                 IPW_PIN_SETRTS,
                                 0,
                                 NULL,
                                 0,
                                 200000);
        if (result < 0)
                dev_err(&port->dev, "setting dtr failed (error = %d)\n", result);
        
        kfree(buf_flow_init);
        return 0;
}

static void ipw_close(struct usb_serial_port *port, struct file * filp)
{
        struct usb_device *dev = port->serial->dev;
        int result;

        if (tty_hung_up_p(filp)) {
                dbg("%s: tty_hung_up_p ...", __FUNCTION__);
                return;
        }

        /*--1: drop the dtr */
        dbg("%s:dropping dtr",__FUNCTION__);
        result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
                                 IPW_SIO_SET_PIN,
                                 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
                                 IPW_PIN_CLRDTR,
                                 0,
                                 NULL,
                                 0,
                                 200000);
        if (result < 0)
                dev_err(&port->dev, "dropping dtr failed (error = %d)\n", result);

        /*--2: drop the rts */
        dbg("%s:dropping rts",__FUNCTION__);
        result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
                                 IPW_SIO_SET_PIN, USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
                                 IPW_PIN_CLRRTS,
                                 0,
                                 NULL,
                                 0,
                                 200000);
        if (result < 0)
                dev_err(&port->dev, "dropping rts failed (error = %d)\n", result);


        /*--3: purge */
        dbg("%s:sending purge",__FUNCTION__);
        result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
                                 IPW_SIO_PURGE, USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
                                 0x03,
                                 0,
                                 NULL,
                                 0,
                                 200000);
        if (result < 0)
                dev_err(&port->dev, "purge failed (error = %d)\n", result);


        /* send RXBULK_off (tell modem to stop transmitting bulk data on rx chan) */
        result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
                                 IPW_SIO_RXCTL,
                                 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
                                 IPW_RXBULK_OFF,
                                 0, /* index */
                                 NULL,
                                 0,
                                 100000);

        if (result < 0)
                dev_err(&port->dev, "Disabling bulk RxRead failed (error = %d)\n", result);

        /* shutdown any in-flight urbs that we know about */
        usb_kill_urb(port->read_urb);
        usb_kill_urb(port->write_urb);
}

static void ipw_write_bulk_callback(struct urb *urb)
{
        struct usb_serial_port *port = urb->context;
        int status = urb->status;

        dbg("%s", __FUNCTION__);

        port->write_urb_busy = 0;

        if (status)
                dbg("%s - nonzero write bulk status received: %d",
                    __FUNCTION__, status);

        usb_serial_port_softint(port);
}

static int ipw_write(struct usb_serial_port *port, const unsigned char *buf, int count)
{
        struct usb_device *dev = port->serial->dev;
        int ret;

        dbg("%s: TOP: count=%d, in_interrupt=%ld", __FUNCTION__,
                count, in_interrupt() );

        if (count == 0) {
                dbg("%s - write request of 0 bytes", __FUNCTION__);
                return 0;
        }

        spin_lock_bh(&port->lock);
        if (port->write_urb_busy) {
                spin_unlock_bh(&port->lock);
                dbg("%s - already writing", __FUNCTION__);
                return 0;
        }
        port->write_urb_busy = 1;
        spin_unlock_bh(&port->lock);

        count = min(count, port->bulk_out_size);
        memcpy(port->bulk_out_buffer, buf, count);

        dbg("%s count now:%d", __FUNCTION__, count);

        usb_fill_bulk_urb(port->write_urb, dev,
                          usb_sndbulkpipe(dev, port->bulk_out_endpointAddress),
                          port->write_urb->transfer_buffer,
                          count,
                          ipw_write_bulk_callback,
                          port);

        ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
        if (ret != 0) {
                port->write_urb_busy = 0;
                dbg("%s - usb_submit_urb(write bulk) failed with error = %d", __FUNCTION__, ret);
                return ret;
        }

        dbg("%s returning %d", __FUNCTION__, count);
        return count;
} 

static int ipw_probe(struct usb_serial_port *port)
{
        return 0;
}

static int ipw_disconnect(struct usb_serial_port *port)
{
        usb_set_serial_port_data(port, NULL);
        return 0;
}

static struct usb_serial_driver ipw_device = {
        .driver = {
                .owner =        THIS_MODULE,
                .name =         "ipw",
        },
        .description =          "IPWireless converter",
        .usb_driver =           &usb_ipw_driver,
        .id_table =             usb_ipw_ids,
        .num_interrupt_in =     NUM_DONT_CARE,
        .num_bulk_in =          1,
        .num_bulk_out =         1,
        .num_ports =            1,
        .open =                 ipw_open,
        .close =                ipw_close,
        .port_probe =           ipw_probe,
        .port_remove =          ipw_disconnect,
        .write =                ipw_write,
        .write_bulk_callback =  ipw_write_bulk_callback,
        .read_bulk_callback =   ipw_read_bulk_callback,
};



static int usb_ipw_init(void)
{
        int retval;

        retval = usb_serial_register(&ipw_device);
        if (retval)
                return retval;
        retval = usb_register(&usb_ipw_driver);
        if (retval) {
                usb_serial_deregister(&ipw_device);
                return retval;
        }
        info(DRIVER_DESC " " DRIVER_VERSION);
        return 0;
}

static void usb_ipw_exit(void)
{
        usb_deregister(&usb_ipw_driver);
        usb_serial_deregister(&ipw_device);
}

module_init(usb_ipw_init);
module_exit(usb_ipw_exit);

/* Module information */
MODULE_AUTHOR( DRIVER_AUTHOR );
MODULE_DESCRIPTION( DRIVER_DESC );
MODULE_LICENSE("GPL");

module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");