pcan_pci_linux.c

linux下的CAN BUS驱动代码。适合在arm平台使用。

//****************************************************************************
// Copyright (C) 2001-2007  PEAK System-Technik GmbH
//
// [e-mail]
// www.peak-system.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.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
//
// Maintainer(s): Klaus Hitschler ([e-mail])
//
// Major contributions by:
//                Edouard Tisserant ([e-mail]) XENOMAI
//                Laurent Bessard   ([e-mail])   XENOMAI
//                Oliver Hartkopp   ([e-mail]) socketCAN
//
//****************************************************************************

//****************************************************************************
//
// all parts to handle device interface specific for pcan-pci
//
// $Id: pcan_pci_linux.c $
//
//****************************************************************************

//****************************************************************************
// DEFINES
#define PCI_FREE_IRQ() free_irq(dev->port.pci.wIrq, dev)

//****************************************************************************
// CODE

// a special frame around the default irq handler
static irqreturn_t IRQHANDLER(pcan_pci_irqhandler, int irq, void *dev_id, struct pt_regs *regs)
{
  struct pcandev *dev = (struct pcandev *)dev_id;
  int ret;

  #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0)
  ret = IRQHANDLER(sja1000_irqhandler, irq, dev_id, regs);
  #else
  IRQHANDLER(sja1000_irqhandler, irq, dev_id, regs);
  ret = 0; // supress warning about unused variable
  #endif

  pcan_pci_clear_stored_interrupt(dev);

  return PCAN_IRQ_RETVAL(ret);
}

// all about interrupt handling
static int pcan_pci_req_irq(struct pcandev *dev)
{
  int err;

  if (dev->wInitStep == 5)
  {
    if ((err = request_irq(dev->port.pci.wIrq, pcan_pci_irqhandler, IRQF_DISABLED | IRQF_SHARED, "pcan", dev)))
      return err;

    pcan_pci_enable_interrupt(dev);
  }

  return 0;
}