Staging: dt3155_drv.c: dereference dt3155_status[]
[firefly-linux-kernel-4.4.55.git] / drivers / staging / dt3155 / dt3155_drv.c
index 88c9e5990bd1f02b294b9111df4b334e68204c6b..6d35a6f1982aeb375268b3bd17cb1e0f68314c68 100644 (file)
@@ -135,6 +135,9 @@ u32 unique_tag = 0;;
  */
 static void quick_stop (int minor)
 {
+  struct dt3155_status *dts = &dt3155_status[minor];
+  struct dt3155_fbuffer *fb = &dts->fbuffer;
+
   // TODO: scott was here
 #if 1
   int_csr_r.reg = readl(dt3155_lbase[minor] + INT_CSR);
@@ -143,14 +146,14 @@ static void quick_stop (int minor)
   int_csr_r.fld.FLD_END_ODD_EN = 0;
   writel(int_csr_r.reg, dt3155_lbase[minor] + INT_CSR);
 
-  dt3155_status[minor].state &= ~(DT3155_STATE_STOP|0xff);
+  dts->state &= ~(DT3155_STATE_STOP|0xff);
   /* mark the system stopped: */
-  dt3155_status[minor].state |= DT3155_STATE_IDLE;
-  dt3155_fbuffer[minor]->stop_acquire = 0;
-  dt3155_fbuffer[minor]->even_stopped = 0;
+  dts->state |= DT3155_STATE_IDLE;
+  fb->stop_acquire = 0;
+  fb->even_stopped = 0;
 #else
-  dt3155_status[minor].state |= DT3155_STATE_STOP;
-  dt3155_status[minor].fbuffer.stop_acquire = 1;
+  dts->state |= DT3155_STATE_STOP;
+  fb->stop_acquire = 1;
 #endif
 
 }
@@ -170,6 +173,8 @@ static void dt3155_isr(int irq, void *dev_id, struct pt_regs *regs)
   unsigned long flags;
   u32 buffer_addr;
   void __iomem *mmio;
+  struct dt3155_status *dts;
+  struct dt3155_fbuffer *fb;
 
   /* find out who issued the interrupt */
   for (index = 0; index < ndevices; index++) {
@@ -187,6 +192,8 @@ static void dt3155_isr(int irq, void *dev_id, struct pt_regs *regs)
   }
 
   mmio = dt3155_lbase[minor];
+  dts = &dt3155_status[minor];
+  fb = &dts->fbuffer;
 
   /* Check for corruption and set a flag if so */
   csr1_r.reg = readl(mmio + CSR1);
@@ -206,10 +213,9 @@ static void dt3155_isr(int irq, void *dev_id, struct pt_regs *regs)
   /* Handle the even field ... */
   if (int_csr_r.fld.FLD_END_EVE)
     {
-      if ((dt3155_status[minor].state & DT3155_STATE_MODE) ==
-          DT3155_STATE_FLD)
+      if ((dts->state & DT3155_STATE_MODE) == DT3155_STATE_FLD)
        {
-         dt3155_fbuffer[minor]->frame_count++;
+         fb->frame_count++;
        }
 
       ReadI2C(mmio, EVEN_CSR, &i2c_even_csr.reg);
@@ -218,10 +224,10 @@ static void dt3155_isr(int irq, void *dev_id, struct pt_regs *regs)
       int_csr_r.fld.FLD_END_EVE = 1;
 
       /* disable the interrupt if last field */
-      if (dt3155_fbuffer[minor]->stop_acquire)
+      if (fb->stop_acquire)
        {
          printk("dt3155:  even stopped.\n");
-         dt3155_fbuffer[minor]->even_stopped = 1;
+         fb->even_stopped = 1;
          if (i2c_even_csr.fld.SNGL_EVE)
            {
              int_csr_r.fld.FLD_END_EVE_EN = 0;
@@ -235,15 +241,13 @@ static void dt3155_isr(int irq, void *dev_id, struct pt_regs *regs)
       writel(int_csr_r.reg, mmio + INT_CSR);
 
       /* Set up next DMA if we are doing FIELDS */
-      if ((dt3155_status[minor].state & DT3155_STATE_MODE) ==
-          DT3155_STATE_FLD)
+      if ((dts->state & DT3155_STATE_MODE) == DT3155_STATE_FLD)
        {
          /* GCS (Aug 2, 2002) -- In field mode, dma the odd field
             into the lower half of the buffer */
-         const u32 stride =  dt3155_status[minor].config.cols;
-         buffer_addr = dt3155_fbuffer[minor]->
-           frame_info[dt3155_fbuffer[minor]->active_buf].addr
-           + (DT3155_MAX_ROWS / 2) * stride;
+         const u32 stride =  dts->config.cols;
+         buffer_addr = fb->frame_info[fb->active_buf].addr +
+                       (DT3155_MAX_ROWS / 2) * stride;
          local_save_flags(flags);
          local_irq_disable();
          wake_up_interruptible(&dt3155_read_wait_queue[minor]);
@@ -262,13 +266,11 @@ static void dt3155_isr(int irq, void *dev_id, struct pt_regs *regs)
 
       /* Note that we actually saw an even field meaning  */
       /* that subsequent odd field complete the frame     */
-      dt3155_fbuffer[minor]->even_happened = 1;
+      fb->even_happened = 1;
 
       /* recording the time that the even field finished, this should be */
       /* about time in the middle of the frame */
-      do_gettimeofday(&(dt3155_fbuffer[minor]->
-                        frame_info[dt3155_fbuffer[minor]->
-                                    active_buf].time));
+      do_gettimeofday(&fb->frame_info[fb->active_buf].time);
       return;
     }
 
@@ -280,30 +282,27 @@ static void dt3155_isr(int irq, void *dev_id, struct pt_regs *regs)
       /* Clear the interrupt? */
       int_csr_r.fld.FLD_END_ODD = 1;
 
-      if (dt3155_fbuffer[minor]->even_happened ||
-         (dt3155_status[minor].state & DT3155_STATE_MODE) ==
-         DT3155_STATE_FLD)
+      if (fb->even_happened ||
+         (dts->state & DT3155_STATE_MODE) == DT3155_STATE_FLD)
        {
-         dt3155_fbuffer[minor]->frame_count++;
+         fb->frame_count++;
        }
 
-      if (dt3155_fbuffer[minor]->stop_acquire &&
-          dt3155_fbuffer[minor]->even_stopped)
+      if (fb->stop_acquire && fb->even_stopped)
        {
          printk(KERN_DEBUG "dt3155:  stopping odd..\n");
          if (i2c_odd_csr.fld.SNGL_ODD)
            {
              /* disable interrupts */
              int_csr_r.fld.FLD_END_ODD_EN = 0;
-             dt3155_status[minor].state &= ~(DT3155_STATE_STOP|0xff);
+             dts->state &= ~(DT3155_STATE_STOP|0xff);
 
              /* mark the system stopped: */
-             dt3155_status[minor].state |= DT3155_STATE_IDLE;
-             dt3155_fbuffer[minor]->stop_acquire = 0;
-             dt3155_fbuffer[minor]->even_stopped = 0;
+             dts->state |= DT3155_STATE_IDLE;
+             fb->stop_acquire = 0;
+             fb->even_stopped = 0;
 
-             printk(KERN_DEBUG "dt3155:  state is now %x\n",
-                    dt3155_status[minor].state);
+             printk(KERN_DEBUG "dt3155:  state is now %x\n", dts->state);
            }
          else
            {
@@ -316,9 +315,8 @@ static void dt3155_isr(int irq, void *dev_id, struct pt_regs *regs)
       /* if the odd field has been acquired, then     */
       /* change the next dma location for both fields */
       /* and wake up the process if sleeping          */
-      if (dt3155_fbuffer[minor]->even_happened ||
-          (dt3155_status[minor].state & DT3155_STATE_MODE) ==
-          DT3155_STATE_FLD)
+      if (fb->even_happened ||
+          (dts->state & DT3155_STATE_MODE) == DT3155_STATE_FLD)
        {
 
          local_save_flags(flags);
@@ -327,7 +325,7 @@ static void dt3155_isr(int irq, void *dev_id, struct pt_regs *regs)
 #ifdef DEBUG_QUES_B
          printques(minor);
 #endif
-         if (dt3155_fbuffer[minor]->nbuffers > 2)
+         if (fb->nbuffers > 2)
            {
              if (!are_empty_buffers(minor))
                {
@@ -341,31 +339,26 @@ static void dt3155_isr(int irq, void *dev_id, struct pt_regs *regs)
              /* The ready_que can't be full, since we know
               * there is one active buffer right now, so it's safe
               * to push the active buf on the ready_que. */
-             push_ready(minor, dt3155_fbuffer[minor]->active_buf);
+             push_ready(minor, fb->active_buf);
              /* There's at least 1 empty -- make it active */
-             dt3155_fbuffer[minor]->active_buf = pop_empty(minor);
-             dt3155_fbuffer[minor]->
-               frame_info[dt3155_fbuffer[minor]->
-                           active_buf].tag = ++unique_tag;
+             fb->active_buf = pop_empty(minor);
+             fb->frame_info[fb->active_buf].tag = ++unique_tag;
            }
          else /* nbuffers == 2, special case */
            { /* There is 1 active buffer.
               * If there is a locked buffer, keep the active buffer
               * the same -- that means we drop a frame.
               */
-             if (dt3155_fbuffer[minor]->locked_buf < 0)
+             if (fb->locked_buf < 0)
                {
-                 push_ready(minor,
-                             dt3155_fbuffer[minor]->active_buf);
+                 push_ready(minor, fb->active_buf);
                  if (are_empty_buffers(minor))
                    {
-                     dt3155_fbuffer[minor]->active_buf =
-                       pop_empty(minor);
+                     fb->active_buf = pop_empty(minor);
                    }
                  else
                    { /* no empty or locked buffers, so use a readybuf */
-                     dt3155_fbuffer[minor]->active_buf =
-                       pop_ready(minor);
+                     fb->active_buf = pop_ready(minor);
                    }
                }
            }
@@ -374,7 +367,7 @@ static void dt3155_isr(int irq, void *dev_id, struct pt_regs *regs)
          printques(minor);
 #endif
 
-         dt3155_fbuffer[minor]->even_happened = 0;
+         fb->even_happened = 0;
 
          wake_up_interruptible(&dt3155_read_wait_queue[minor]);
 
@@ -383,10 +376,8 @@ static void dt3155_isr(int irq, void *dev_id, struct pt_regs *regs)
 
 
       /* Set up the DMA address for the next frame/field */
-      buffer_addr = dt3155_fbuffer[minor]->
-       frame_info[dt3155_fbuffer[minor]->active_buf].addr;
-      if ((dt3155_status[minor].state & DT3155_STATE_MODE) ==
-          DT3155_STATE_FLD)
+      buffer_addr = fb->frame_info[fb->active_buf].addr;
+      if ((dts->state & DT3155_STATE_MODE) == DT3155_STATE_FLD)
        {
          writel(buffer_addr, mmio + EVEN_DMA_START);
        }
@@ -394,8 +385,7 @@ static void dt3155_isr(int irq, void *dev_id, struct pt_regs *regs)
        {
          writel(buffer_addr, mmio + EVEN_DMA_START);
 
-         writel(buffer_addr + dt3155_status[minor].config.cols,
-               mmio + ODD_DMA_START);
+         writel(buffer_addr + dts->config.cols, mmio + ODD_DMA_START);
        }
 
       /* Do error checking */
@@ -419,15 +409,16 @@ static void dt3155_isr(int irq, void *dev_id, struct pt_regs *regs)
  *****************************************************/
 static void dt3155_init_isr(int minor)
 {
-  const u32 stride =  dt3155_status[minor].config.cols;
+  struct dt3155_status *dts = &dt3155_status[minor];
+  struct dt3155_fbuffer *fb = &dts->fbuffer;
+  const u32 stride = dts->config.cols;
   void __iomem *mmio = dt3155_lbase[minor];
 
-  switch (dt3155_status[minor].state & DT3155_STATE_MODE)
+  switch (dts->state & DT3155_STATE_MODE)
     {
     case DT3155_STATE_FLD:
       {
-       even_dma_start_r  = dt3155_status[minor].
-         fbuffer.frame_info[dt3155_status[minor].fbuffer.active_buf].addr;
+       even_dma_start_r  = fb->frame_info[fb->active_buf].addr;
        even_dma_stride_r = 0;
        odd_dma_stride_r  = 0;
 
@@ -440,8 +431,7 @@ static void dt3155_init_isr(int minor)
     case DT3155_STATE_FRAME:
     default:
       {
-       even_dma_start_r  = dt3155_status[minor].
-         fbuffer.frame_info[dt3155_status[minor].fbuffer.active_buf].addr;
+       even_dma_start_r  = fb->frame_info[fb->active_buf].addr;
        odd_dma_start_r   =  even_dma_start_r + stride;
        even_dma_stride_r =  stride;
        odd_dma_stride_r  =  stride;
@@ -514,6 +504,8 @@ static int dt3155_ioctl(struct inode *inode,
 {
   int minor = MINOR(inode->i_rdev); /* What device are we ioctl()'ing? */
   void __user *up = (void __user *)arg;
+  struct dt3155_status *dts = &dt3155_status[minor];
+  struct dt3155_fbuffer *fb = &dts->fbuffer;
 
   if (minor >= MAXBOARDS || minor < 0)
     return -ENODEV;
@@ -535,7 +527,7 @@ static int dt3155_ioctl(struct inode *inode,
     {
     case DT3155_SET_CONFIG:
       {
-       if (dt3155_status[minor].state != DT3155_STATE_IDLE)
+       if (dts->state != DT3155_STATE_IDLE)
          return -EBUSY;
 
        {
@@ -552,59 +544,55 @@ static int dt3155_ioctl(struct inode *inode,
            {
              return -EINVAL;
            }
-         dt3155_status[minor].config = tmp;
+         dts->config = tmp;
        }
        return 0;
       }
     case DT3155_GET_CONFIG:
       {
-       if (copy_to_user(up, &dt3155_status[minor],
-                    sizeof(struct dt3155_status)))
+       if (copy_to_user(up, dts, sizeof(*dts)))
            return -EFAULT;
        return 0;
       }
     case DT3155_FLUSH: /* Flushes the buffers -- ensures fresh data */
       {
-       if (dt3155_status[minor].state != DT3155_STATE_IDLE)
+       if (dts->state != DT3155_STATE_IDLE)
          return -EBUSY;
        return dt3155_flush(minor);
       }
     case DT3155_STOP:
       {
-       if (dt3155_status[minor].state & DT3155_STATE_STOP ||
-           dt3155_status[minor].fbuffer.stop_acquire)
+       if (dts->state & DT3155_STATE_STOP || fb->stop_acquire)
          return -EBUSY;
 
-       if (dt3155_status[minor].state == DT3155_STATE_IDLE)
+       if (dts->state == DT3155_STATE_IDLE)
          return 0;
 
        quick_stop(minor);
-       if (copy_to_user(up, &dt3155_status[minor],
-                    sizeof(struct dt3155_status)))
+       if (copy_to_user(up, dts, sizeof(*dts)))
            return -EFAULT;
        return 0;
       }
     case DT3155_START:
       {
-       if (dt3155_status[minor].state != DT3155_STATE_IDLE)
+       if (dts->state != DT3155_STATE_IDLE)
          return -EBUSY;
 
-       dt3155_status[minor].fbuffer.stop_acquire = 0;
-       dt3155_status[minor].fbuffer.frame_count = 0;
+       fb->stop_acquire = 0;
+       fb->frame_count = 0;
 
        /* Set the MODE in the status -- we default to FRAME */
-       if (dt3155_status[minor].config.acq_mode == DT3155_MODE_FIELD)
+       if (dts->config.acq_mode == DT3155_MODE_FIELD)
          {
-           dt3155_status[minor].state = DT3155_STATE_FLD;
+           dts->state = DT3155_STATE_FLD;
          }
        else
          {
-           dt3155_status[minor].state = DT3155_STATE_FRAME;
+           dts->state = DT3155_STATE_FRAME;
          }
 
        dt3155_init_isr(minor);
-       if (copy_to_user(up, &dt3155_status[minor],
-                     sizeof(struct dt3155_status)))
+       if (copy_to_user(up, dts, sizeof(*dts)))
            return -EFAULT;
        return 0;
       }
@@ -633,7 +621,8 @@ static int dt3155_ioctl(struct inode *inode,
 static int dt3155_mmap (struct file * file, struct vm_area_struct * vma)
 {
   /* which device are we mmapping? */
-  int                          minor = MINOR(file->f_dentry->d_inode->i_rdev);
+  int minor = MINOR(file->f_dentry->d_inode->i_rdev);
+  struct dt3155_status *dts = &dt3155_status[minor];
   unsigned long        offset;
   offset = vma->vm_pgoff << PAGE_SHIFT;
 
@@ -644,10 +633,10 @@ static int dt3155_mmap (struct file * file, struct vm_area_struct * vma)
   vma->vm_flags |= VM_RESERVED;
 
   /* they are mapping the registers or the buffer */
-  if ((offset == dt3155_status[minor].reg_addr &&
+  if ((offset == dts->reg_addr &&
        vma->vm_end - vma->vm_start == PCI_PAGE_SIZE) ||
-      (offset == dt3155_status[minor].mem_addr &&
-       vma->vm_end - vma->vm_start == dt3155_status[minor].mem_size))
+      (offset == dts->mem_addr &&
+       vma->vm_end - vma->vm_start == dts->mem_size))
     {
       if (remap_pfn_range(vma,
                        vma->vm_start,
@@ -678,21 +667,23 @@ static int dt3155_mmap (struct file * file, struct vm_area_struct * vma)
 static int dt3155_open(struct inode* inode, struct file* filep)
 {
   int minor = MINOR(inode->i_rdev); /* what device are we opening? */
+  struct dt3155_status *dts = &dt3155_status[minor];
+
   if (dt3155_dev_open[minor]) {
     printk ("DT3155:  Already opened by another process.\n");
     return -EBUSY;
   }
 
-  if (dt3155_status[minor].device_installed==0)
+  if (dts->device_installed==0)
     {
       printk("DT3155 Open Error: No such device dt3155 minor number %d\n",
             minor);
       return -EIO;
     }
 
-  if (dt3155_status[minor].state != DT3155_STATE_IDLE) {
+  if (dts->state != DT3155_STATE_IDLE) {
     printk ("DT3155:  Not in idle state (state = %x)\n",
-           dt3155_status[minor].state);
+           dts->state);
     return -EBUSY;
   }
 
@@ -720,9 +711,9 @@ static int dt3155_open(struct inode* inode, struct file* filep)
  *****************************************************/
 static int dt3155_close(struct inode *inode, struct file *filep)
 {
-  int minor;
+  int minor = MINOR(inode->i_rdev); /* which device are we closing */
+  struct dt3155_status *dts = &dt3155_status[minor];
 
-  minor = MINOR(inode->i_rdev); /* which device are we closing */
   if (!dt3155_dev_open[minor])
     {
       printk("DT3155: attempt to CLOSE a not OPEN device\n");
@@ -731,7 +722,7 @@ static int dt3155_close(struct inode *inode, struct file *filep)
     {
       dt3155_dev_open[minor] = 0;
 
-      if (dt3155_status[minor].state != DT3155_STATE_IDLE)
+      if (dts->state != DT3155_STATE_IDLE)
        {
          quick_stop(minor);
        }
@@ -750,6 +741,8 @@ static ssize_t dt3155_read(struct file *filep, char __user *buf,
   int          minor = MINOR(filep->f_dentry->d_inode->i_rdev);
   u32          offset;
   int          frame_index;
+  struct dt3155_status *dts = &dt3155_status[minor];
+  struct dt3155_fbuffer *fb = &dts->fbuffer;
   struct frame_info    *frame_info;
 
   /* TODO: this should check the error flag and */
@@ -768,7 +761,7 @@ static ssize_t dt3155_read(struct file *filep, char __user *buf,
    * Note that if the driver is not opened in non_blocking mode,
    * and the device is idle, then it could sit here forever! */
 
-  /*  if (dt3155_status[minor].state == DT3155_STATE_IDLE)*/
+  /*  if (dts->state == DT3155_STATE_IDLE)*/
   /*    return -EBUSY;*/
 
   /* non-blocking reads should return if no data */
@@ -800,16 +793,16 @@ static ssize_t dt3155_read(struct file *filep, char __user *buf,
        }
     }
 
-  frame_info = &dt3155_status[minor].fbuffer.frame_info[frame_index];
+  frame_info = &fb->frame_info[frame_index];
 
   /* make this an offset */
-  offset = frame_info->addr - dt3155_status[minor].mem_addr;
+  offset = frame_info->addr - dts->mem_addr;
 
   put_user(offset, (unsigned int __user *)buf);
   buf += sizeof(u32);
-  put_user(dt3155_status[minor].fbuffer.frame_count, (unsigned int __user *)buf);
+  put_user(fb->frame_count, (unsigned int __user *)buf);
   buf += sizeof(u32);
-  put_user(dt3155_status[minor].state, (unsigned int __user *)buf);
+  put_user(dts->state, (unsigned int __user *)buf);
   buf += sizeof(u32);
   if (copy_to_user(buf, frame_info, sizeof(*frame_info)))
       return -EFAULT;
@@ -864,6 +857,7 @@ static struct file_operations dt3155_fops = {
 static int find_PCI (void)
 {
   struct pci_dev *pci_dev = NULL;
+  struct dt3155_status *dts;
   int error, pci_index = 0;
   unsigned short rev_device;
   unsigned long base;
@@ -872,7 +866,7 @@ static int find_PCI (void)
   while ((pci_dev = pci_get_device
          (DT3155_VENDORID, DT3155_DEVICEID, pci_dev)) != NULL)
     {
-      pci_index ++;
+      dts = &dt3155_status[pci_index++];
 
       /* Is it really there? */
       if ((error =
@@ -902,12 +896,12 @@ static int find_PCI (void)
        }
 
       DT_3155_DEBUG_MSG("DT3155: Base address 0 for device is %lx \n", base);
-      dt3155_status[pci_index-1].reg_addr = base;
+      dts->reg_addr = base;
 
       /* Remap the base address to a logical address through which we
        * can access it. */
       dt3155_lbase[pci_index - 1] = ioremap(base, PCI_PAGE_SIZE);
-      dt3155_status[pci_index - 1].reg_addr = base;
+      dts->reg_addr = base;
       DT_3155_DEBUG_MSG("DT3155: New logical address is %p \n",
                        dt3155_lbase[pci_index-1]);
       if (!dt3155_lbase[pci_index-1])
@@ -923,12 +917,12 @@ static int find_PCI (void)
        }
 
       DT_3155_DEBUG_MSG("DT3155: IRQ is %d \n",irq);
-      dt3155_status[pci_index-1].irq = irq;
+      dts->irq = irq;
       /* Set flag: kth device found! */
-      dt3155_status[pci_index-1].device_installed = 1;
+      dts->device_installed = 1;
       printk("DT3155: Installing device %d w/irq %d and address %p\n",
             pci_index,
-            dt3155_status[pci_index-1].irq,
+            dts->irq,
             dt3155_lbase[pci_index-1]);
 
     }
@@ -948,6 +942,7 @@ u32 allocatorAddr = 0;
  *****************************************************/
 int init_module(void)
 {
+  struct dt3155_status *dts;
   int index;
   int rcode = 0;
   char *devname[MAXBOARDS];
@@ -975,18 +970,20 @@ int init_module(void)
   /* DMA memory is taken care of in setup_buffers() */
   for (index = 0; index < MAXBOARDS; index++)
     {
-      dt3155_status[index].config.acq_mode   = DT3155_MODE_FRAME;
-      dt3155_status[index].config.continuous = DT3155_ACQ;
-      dt3155_status[index].config.cols       = DT3155_MAX_COLS;
-      dt3155_status[index].config.rows       = DT3155_MAX_ROWS;
-      dt3155_status[index].state = DT3155_STATE_IDLE;
+      dts = &dt3155_status[index];
+
+      dts->config.acq_mode   = DT3155_MODE_FRAME;
+      dts->config.continuous = DT3155_ACQ;
+      dts->config.cols       = DT3155_MAX_COLS;
+      dts->config.rows       = DT3155_MAX_ROWS;
+      dts->state = DT3155_STATE_IDLE;
 
       /* find_PCI() will check if devices are installed; */
       /* first assume they're not:                       */
-      dt3155_status[index].mem_addr          = 0;
-      dt3155_status[index].mem_size          = 0;
-      dt3155_status[index].state             = DT3155_STATE_IDLE;
-      dt3155_status[index].device_installed  = 0;
+      dts->mem_addr          = 0;
+      dts->mem_size          = 0;
+      dts->state             = DT3155_STATE_IDLE;
+      dts->device_installed  = 0;
     }
 
   /* Now let's find the hardware.  find_PCI() will set ndevices to the
@@ -1012,27 +1009,31 @@ int init_module(void)
   /* for the buffers: Print the configuration.    */
   for( index = 0;  index < ndevices;  index++)
     {
+      dts = &dt3155_status[index];
+
       printk("DT3155: Device = %d; acq_mode = %d; "
             "continuous = %d; cols = %d; rows = %d;\n",
             index ,
-            dt3155_status[index].config.acq_mode,
-            dt3155_status[index].config.continuous,
-            dt3155_status[index].config.cols,
-            dt3155_status[index].config.rows);
+            dts->config.acq_mode,
+            dts->config.continuous,
+            dts->config.cols,
+            dts->config.rows);
       printk("DT3155: m_addr = 0x%x; m_size = %ld; "
             "state = %d; device_installed = %d\n",
-            dt3155_status[index].mem_addr,
-            (long int)dt3155_status[index].mem_size,
-            dt3155_status[index].state,
-            dt3155_status[index].device_installed);
+            dts->mem_addr,
+            (long int)dts->mem_size,
+            dts->state,
+            dts->device_installed);
     }
 
   /* Disable ALL interrupts */
   int_csr_r.reg = 0;
   for( index = 0;  index < ndevices;  index++)
     {
+      dts = &dt3155_status[index];
+
       writel(int_csr_r.reg, dt3155_lbase[index] + INT_CSR);
-      if(dt3155_status[index].device_installed)
+      if(dts->device_installed)
        {
          /*
           * This driver *looks* like it can handle sharing interrupts,
@@ -1041,13 +1042,13 @@ int init_module(void)
           * as a reminder in case any problems arise. (SS)
           */
          /* in older kernels flags are: SA_SHIRQ | SA_INTERRUPT */
-         rcode = request_irq(dt3155_status[index].irq, (void *)dt3155_isr,
+         rcode = request_irq(dts->irq, (void *)dt3155_isr,
                               IRQF_SHARED | IRQF_DISABLED, devname[index],
-                              (void*) &dt3155_status[index]);
+                              (void *)dts);
          if(rcode < 0)
            {
              printk("DT3155: minor %d request_irq failed for IRQ %d\n",
-                    index, dt3155_status[index].irq);
+                    index, dts->irq);
              unregister_chrdev(dt3155_major, "dt3155");
              return rcode;
            }
@@ -1065,6 +1066,7 @@ int init_module(void)
  *****************************************************/
 void cleanup_module(void)
 {
+  struct dt3155_status *dts;
   int index;
 
   printk("DT3155:  cleanup_module called\n");
@@ -1081,11 +1083,12 @@ void cleanup_module(void)
 
   for(index = 0; index < ndevices; index++)
     {
-      if(dt3155_status[index].device_installed == 1)
+      dts = &dt3155_status[index];
+      if(dts->device_installed == 1)
        {
          printk("DT3155: Freeing irq %d for device %d\n",
-                 dt3155_status[index].irq, index);
-         free_irq(dt3155_status[index].irq, (void*)&dt3155_status[index]);
+                 dts->irq, index);
+         free_irq(dts->irq, (void *)dts);
        }
     }
 }