All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH 1/1] mct_u232: IOCTL implementation
@ 2010-12-26  5:39 Tsozik
  2010-12-26 17:49 ` Pete Zaitcev
  2010-12-26 18:41 ` Greg KH
  0 siblings, 2 replies; 11+ messages in thread
From: Tsozik @ 2010-12-26  5:39 UTC (permalink / raw)
  To: Greg Kroah-Hartman, linux-usb; +Cc: linux-kernel

From: Vadim Tsozik <tsozik@yahoo.com>

Added mct_u232_ioctl function and implemented TIOCMIWAIT and TIOCGICOUNT commands. MCT u232 p9 is one of a few usb to serail adapters which converts USB +/-5v voltage levels to COM +/-15 voltages. So it can also power COM interfaced devices. This makes it very usable for legacy COM interfaced data-acquisition hardware. I tested new implementation with AWARE Electronics RM-60 radiation meter, which sends pulse via RNG COM line whenever new particle is registered.

Patch below is based on linux-2.6.35.10-72.fc14.x86_64.

Signed-off-by: Vadim Tsozik <tsozik@yahoo.com>

---
--- original/mct_u232.c 2010-12-25 21:31:13.744174626 -0500
+++ mct_u232.c  2010-12-25 21:44:57.714640343 -0500
@@ -24,6 +24,12 @@
  *   Basic tests have been performed with minicom/zmodem transfers and
  *   modem dialing under Linux 2.4.0-test10 (for me it works fine).
  *
+ * 24-Apr-2010 Vadim Tsozik <tsozik@yahoo.com>
+ *   - Added implementation of 'TIOCMIWAIT' and 'TIOCGICOUNT' ioctls.
+ *     This routines are necessary if you use mct u232 p9 as data
+ *     acquisition interface. These routines were tested with RM-60 AWARE
+ *     Electronics Radiation Monitor.
+ *
  * 04-Nov-2003 Bill Marr <marr at flex dot com>
  *   - Mimic Windows driver by sending 2 USB 'device request' messages
  *     following normal 'baud rate change' message.  This allows data to be
@@ -78,6 +84,8 @@
 #include <asm/unaligned.h>
 #include <linux/usb.h>
 #include <linux/usb/serial.h>
+#include <linux/serial.h>
+#include <linux/ioctl.h>
 #include "mct_u232.h"

 /*
@@ -104,6 +112,8 @@ static void mct_u232_break_ctl(struct tt
 static int  mct_u232_tiocmget(struct tty_struct *tty, struct file *file);
 static int  mct_u232_tiocmset(struct tty_struct *tty, struct file *file,
                        unsigned int set, unsigned int clear);
+static int  mct_u232_ioctl(struct tty_struct *tty, struct file *file,
+                        unsigned int cmd, unsigned long arg);
 static void mct_u232_throttle(struct tty_struct *tty);
 static void mct_u232_unthrottle(struct tty_struct *tty);

@@ -150,6 +160,7 @@ static struct usb_serial_driver mct_u232
        .tiocmset =          mct_u232_tiocmset,
        .attach =            mct_u232_startup,
        .release =           mct_u232_release,
+       .ioctl =             mct_u232_ioctl,
 };


@@ -160,6 +171,8 @@ struct mct_u232_private {
        unsigned char        last_lsr;      /* Line Status Register */
        unsigned char        last_msr;      /* Modem Status Register */
        unsigned int         rx_flags;      /* Throttling flags */
+        struct async_icount  icount;
+       wait_queue_head_t    msr_wait;      /* for handling sleeping while waiting for msr change to happen */
 };

 #define THROTTLED              0x01
@@ -386,27 +399,41 @@ static int mct_u232_get_modem_stat(struc
        return rc;
 } /* mct_u232_get_modem_stat */

-static void mct_u232_msr_to_state(unsigned int *control_state,
-                                               unsigned char msr)
+static void mct_u232_msr_to_state(struct mct_u232_private *priv)
 {
-       /* Translate Control Line states */
-       if (msr & MCT_U232_MSR_DSR)
-               *control_state |=  TIOCM_DSR;
-       else
-               *control_state &= ~TIOCM_DSR;
-       if (msr & MCT_U232_MSR_CTS)
-               *control_state |=  TIOCM_CTS;
-       else
-               *control_state &= ~TIOCM_CTS;
-       if (msr & MCT_U232_MSR_RI)
-               *control_state |=  TIOCM_RI;
-       else
-               *control_state &= ~TIOCM_RI;
-       if (msr & MCT_U232_MSR_CD)
-               *control_state |=  TIOCM_CD;
-       else
-               *control_state &= ~TIOCM_CD;
-       dbg("msr_to_state: msr=0x%x ==> state=0x%x", msr, *control_state);
+        unsigned char msr = priv->last_msr;
+        unsigned int *control_state = &priv->control_state;
+        struct async_icount *icount = &priv->icount;
+
+        /* Translate Control Line states */
+        if (msr & MCT_U232_MSR_DSR) {
+         *control_state |=  TIOCM_DSR;
+         icount->dsr++;
+        } else {
+         *control_state &= ~TIOCM_DSR;
+        }
+        if (msr & MCT_U232_MSR_CTS) {
+         *control_state |=  TIOCM_CTS;
+         icount->cts++;
+        } else {
+         *control_state &= ~TIOCM_CTS;
+        }
+        if (msr & MCT_U232_MSR_RI) {
+         *control_state |=  TIOCM_RI;
+         icount->rng++;
+        } else {
+         *control_state &= ~TIOCM_RI;
+        }
+        if (msr & MCT_U232_MSR_CD) {
+         *control_state |=  TIOCM_CD;
+         icount->dcd++;
+        } else {
+         *control_state &= ~TIOCM_CD;
+        }
+
+        dbg("msr_to_state: msr=0x%x ==> state=0x%x", msr, *control_state);
+
+        wake_up_interruptible(&priv->msr_wait);
 } /* mct_u232_msr_to_state */

 /*
@@ -422,6 +449,7 @@ static int mct_u232_startup(struct usb_s
        if (!priv)
                return -ENOMEM;
        spin_lock_init(&priv->lock);
+       init_waitqueue_head(&priv->msr_wait);
        usb_set_serial_port_data(serial->port[0], priv);

        init_waitqueue_head(&serial->port[0]->write_wait);
@@ -498,7 +526,7 @@ static int  mct_u232_open(struct tty_str
        mct_u232_get_modem_stat(serial, &last_msr);
        spin_lock_irqsave(&priv->lock, flags);
        priv->last_msr = last_msr;
-       mct_u232_msr_to_state(&priv->control_state, priv->last_msr);
+       mct_u232_msr_to_state(priv);
        spin_unlock_irqrestore(&priv->lock, flags);

        port->read_urb->dev = port->serial->dev;
@@ -616,7 +644,7 @@ static void mct_u232_read_int_callback(s
        priv->last_msr = data[MCT_U232_MSR_INDEX];

        /* Record Control Line states */
-       mct_u232_msr_to_state(&priv->control_state, priv->last_msr);
+       mct_u232_msr_to_state(priv);

 #if 0
        /* Not yet handled. See belkin_sa.c for further information */
@@ -823,7 +851,6 @@ static void mct_u232_throttle(struct tty
        }
 }

-
 static void mct_u232_unthrottle(struct tty_struct *tty)
 {
        struct usb_serial_port *port = tty->driver_data;
@@ -844,6 +871,57 @@ static void mct_u232_unthrottle(struct t
        }
 }

+static int  mct_u232_ioctl(struct tty_struct *tty, struct file *file,
+                        unsigned int cmd, unsigned long arg)
+{
+       DEFINE_WAIT(wait);
+       struct usb_serial_port *port = tty->driver_data;
+       struct mct_u232_private *mct_u232_port = usb_get_serial_port_data(port);
+       struct async_icount cnow, cprev;
+
+       dbg("%s - port %d, cmd = 0x%x", __func__, port->number, cmd);
+
+       switch (cmd) {
+
+       case TIOCMIWAIT:
+
+               dbg("%s (%d) TIOCMIWAIT", __func__,  port->number);
+
+               cprev = mct_u232_port->icount;
+               for ( ; ; ) {
+                       prepare_to_wait(&mct_u232_port->msr_wait,
+                                               &wait, TASK_INTERRUPTIBLE);
+                       schedule();
+                       finish_wait(&mct_u232_port->msr_wait, &wait);
+                       /* see if a signal did it */
+                       if (signal_pending(current))
+                               return -ERESTARTSYS;
+                       cnow = mct_u232_port->icount;
+                       if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
+                           cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
+                               return -EIO; /* no change => error */
+                       if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
+                           ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
+                           ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
+                           ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) {
+                               return 0;
+                       }
+                       cprev = cnow;
+               }
+               /* NOTREACHED */
+               break;
+
+       case TIOCGICOUNT:
+                dbg("%s - (%d) TIOCGICOUNT RX=%d, TX=%d", __func__,
+                    port->number, mct_u232_port->icount.rx, mct_u232_port->icount.tx);
+                if (copy_to_user((void __user *)arg, &mct_u232_port->icount,
+                    sizeof(mct_u232_port->icount)))
+                        return -EFAULT;
+                return 0;
+       }
+       return -ENOIOCTLCMD;
+}
+
 static int __init mct_u232_init(void)
 {
        int retval;



      

^ permalink raw reply	[flat|nested] 11+ messages in thread
* Re: [PATCH 1/1] mct_u232: IOCTL implementation
@ 2010-12-26 22:14 Tsozik
  2010-12-27  0:28 ` Pete Zaitcev
  0 siblings, 1 reply; 11+ messages in thread
From: Tsozik @ 2010-12-26 22:14 UTC (permalink / raw)
  To: Pete Zaitcev; +Cc: Greg Kroah-Hartman, linux-usb, linux-kernel

Pete,

My apology, reading Greg's post I realized that 2.6.35 (distributed with Fedora 14) is indeed outdated. I just checked out 2.6.37-rc7 tree and saw references to get_icount function. I will definetely address your concern,

Thank you again,
 Vadim.

--- On Sun, 12/26/10, Tsozik <tsozik@yahoo.com> wrote:

> From: Tsozik <tsozik@yahoo.com>
> Subject: Re: [PATCH 1/1] mct_u232: IOCTL implementation
> To: "Pete Zaitcev" <zaitcev@redhat.com>
> Cc: "Greg Kroah-Hartman" <gregkh@suse.de>, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
> Date: Sunday, December 26, 2010, 2:41 PM
> Pete,
> 
> Many thanks for your comment/concern. I borrowed an
> TIOCGICOUNT implementation from usb/serial/io_ti.c:
> 
>         case TIOCGICOUNT:
>                
> dbg("%s - (%d) TIOCGICOUNT RX=%d, TX=%d", __func__,
>                
>      port->number,
> edge_port->icount.rx, edge_port->icount.tx);
>                 if
> (copy_to_user((void __user *)arg,
> &edge_port->icount,
>                
>                
> sizeof(edge_port->icount)))
>                
>         return -EFAULT;
>                
> return 0;
>         }
> 
> There are 2 similar TIOCGICOUNT implementations listed in
> 
> ark3116.c
> io_edgeport.c
> io_ti.c
> mos7720.c
> mos7840.c
> ti_usb_3410_5052.c
> 
> files under usb/serial/ directory. One based on io_ti.c and
> another based on io_edgeport.c. I borrowed one from io_ti.c,
> since it looked more effecient to me. I searched for any
> mention of get_icount function under linux-2.6.35 and didn't
> find any file which declared or called this function:
> 
> [vtsozik@SR71 linux-2.6.35]$ find . -type f -name '*.[c,h]'
> | xargs grep get_icount
> [vtsozik@SR71 linux-2.6.35]$
> 
> I'm wondering if you could give me a bit more information
> on this. Otherwise I would really prefer to proceed with
> something that already exists and tested. If by some reason
> you believe that alternative implementation from
> io_edgeport.c (please see code snippet below) should be used
> please let me know. Again I didn't see any reason for extra
> copy.
> 
>         case TIOCGICOUNT:
>                
> cnow = edge_port->icount;
>                
> memset(&icount, 0, sizeof(icount));
>                
> icount.cts = cnow.cts;
>                
> icount.dsr = cnow.dsr;
>                
> icount.rng = cnow.rng;
>                
> icount.dcd = cnow.dcd;
>                
> icount.rx = cnow.rx;
>                
> icount.tx = cnow.tx;
>                
> icount.frame = cnow.frame;
>                
> icount.overrun = cnow.overrun;
>                
> icount.parity = cnow.parity;
>                
> icount.brk = cnow.brk;
>                
> icount.buf_overrun = cnow.buf_overrun;
> 
>                
> dbg("%s (%d) TIOCGICOUNT RX=%d, TX=%d",
>                
>                
> __func__,  port->number, icount.rx, icount.tx);
>                 if
> (copy_to_user((void __user *)arg, &icount,
> sizeof(icount)))
>                
>         return -EFAULT;
>                
> return 0;
>         }
> 
> Thank you in advance,
> Vadim.
> 
> --- On Sun, 12/26/10, Pete Zaitcev <zaitcev@redhat.com>
> wrote:
> 
> > From: Pete Zaitcev <zaitcev@redhat.com>
> > Subject: Re: [PATCH 1/1] mct_u232: IOCTL
> implementation
> > To: "Tsozik" <tsozik@yahoo.com>
> > Cc: "Greg Kroah-Hartman" <gregkh@suse.de>,
> linux-usb@vger.kernel.org,
> linux-kernel@vger.kernel.org
> > Date: Sunday, December 26, 2010, 12:49 PM
> > On Sat, 25 Dec 2010 21:39:39 -0800
> > (PST)
> > Tsozik <tsozik@yahoo.com>
> > wrote:
> > 
> > > +++ mct_u232.c  2010-12-25 21:44:57.714640343
> > -0500
> > > +static int  mct_u232_ioctl(struct tty_struct
> > *tty, struct file *file,
> > > +             
> >           unsigned int cmd,
> > unsigned long arg)
> > > +{
> > > +       case TIOCGICOUNT:
> > > +             
> >   dbg("%s - (%d) TIOCGICOUNT RX=%d, TX=%d",
> __func__,
> > > +             
> >       port->number,
> > mct_u232_port->icount.rx,
> mct_u232_port->icount.tx);
> > > +             
> >   if (copy_to_user((void __user *)arg,
> > &mct_u232_port->icount,
> > > +             
> >       sizeof(mct_u232_port->icount)))
> > > +             
> >           return -EFAULT;
> > 
> > This looks suspicious. Didn't we relocate the
> machinery for
> > TIOCGICOUNT
> > into a generic place? Please examine how
> ->get_icount
> > works before
> > hand-rolling the ioctl.
> > 
> > -- Pete
> > 
> 
> 
> 
> 


      

^ permalink raw reply	[flat|nested] 11+ messages in thread
end of thread, other threads:[~2010-12-27  0:28 UTC | newest]

Thread overview: 11+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-12-26  5:39 [PATCH 1/1] mct_u232: IOCTL implementation Tsozik
2010-12-26 17:49 ` Pete Zaitcev
2010-12-26 19:41   ` Tsozik
2010-12-26 18:41 ` Greg KH
2010-12-26 19:51   ` Tsozik
2010-12-26 21:30     ` Randy Dunlap
2010-12-26 22:01       ` Tsozik
2010-12-26 22:03         ` Jesper Juhl
2010-12-26 23:31           ` Tsozik
  -- strict thread matches above, loose matches on Subject: below --
2010-12-26 22:14 Tsozik
2010-12-27  0:28 ` Pete Zaitcev

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.