These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / drivers / staging / comedi / drivers / das800.c

diff --git a/kernel/drivers/staging/comedi/drivers/das800.c b/kernel/drivers/staging/comedi/drivers/das800.c
index 39d304a..b02f122 100644 (file)
--- a/kernel/drivers/staging/comedi/drivers/das800.c
+++ b/kernel/drivers/staging/comedi/drivers/das800.c
@@ -240,13 +240,13 @@ static unsigned das800_ind_read(struct comedi_device *dev, unsigned reg)
 
 static void das800_enable(struct comedi_device *dev)
 {
-       const struct das800_board *thisboard = dev->board_ptr;
+       const struct das800_board *board = dev->board_ptr;
        struct das800_private *devpriv = dev->private;
        unsigned long irq_flags;
 
        spin_lock_irqsave(&dev->spinlock, irq_flags);
        /*  enable fifo-half full interrupts for cio-das802/16 */
-       if (thisboard->resolution == 16)
+       if (board->resolution == 16)
                outb(CIO_ENHF, dev->iobase + DAS800_GAIN);
        /* enable hardware triggering */
        das800_ind_write(dev, CONV_HCEN, CONV_CONTROL);
@@ -303,7 +303,7 @@ static int das800_ai_do_cmdtest(struct comedi_device *dev,
                                struct comedi_subdevice *s,
                                struct comedi_cmd *cmd)
 {
-       const struct das800_board *thisboard = dev->board_ptr;
+       const struct das800_board *board = dev->board_ptr;
        int err = 0;
 
        /* Step 1 : check if triggers are trivially valid */
@@ -335,7 +335,7 @@ static int das800_ai_do_cmdtest(struct comedi_device *dev,
 
        if (cmd->convert_src == TRIG_TIMER) {
                err |= comedi_check_trigger_arg_min(&cmd->convert_arg,
-                                                   thisboard->ai_speed);
+                                                   board->ai_speed);
        }
 
        err |= comedi_check_trigger_arg_min(&cmd->chanlist_len, 1);
@@ -375,7 +375,7 @@ static int das800_ai_do_cmdtest(struct comedi_device *dev,
 static int das800_ai_do_cmd(struct comedi_device *dev,
                            struct comedi_subdevice *s)
 {
-       const struct das800_board *thisboard = dev->board_ptr;
+       const struct das800_board *board = dev->board_ptr;
        struct comedi_async *async = s->async;
        struct comedi_cmd *cmd = &async->cmd;
        unsigned int gain = CR_RANGE(cmd->chanlist[0]);
@@ -393,7 +393,7 @@ static int das800_ai_do_cmd(struct comedi_device *dev,
        spin_unlock_irqrestore(&dev->spinlock, irq_flags);
 
        /* set gain */
-       if (thisboard->resolution == 12 && gain > 0)
+       if (board->resolution == 12 && gain > 0)
                gain += 0x7;
        gain &= 0xf;
        outb(gain, dev->iobase + DAS800_GAIN);
@@ -604,54 +604,62 @@ static int das800_do_insn_bits(struct comedi_device *dev,
        return insn->n;
 }
 
-static int das800_probe(struct comedi_device *dev)
+static const struct das800_board *das800_probe(struct comedi_device *dev)
 {
-       const struct das800_board *thisboard = dev->board_ptr;
-       int board = thisboard ? thisboard - das800_boards : -EINVAL;
+       const struct das800_board *board = dev->board_ptr;
+       int index = board ? board - das800_boards : -EINVAL;
        int id_bits;
        unsigned long irq_flags;
 
+       /*
+        * The dev->board_ptr will be set by comedi_device_attach() if the
+        * board name provided by the user matches a board->name in this
+        * driver. If so, this function sanity checks the id_bits to verify
+        * that the board is correct.
+        *
+        * If the dev->board_ptr is not set, the user is trying to attach
+        * an unspecified board to this driver. In this case the id_bits
+        * are used to 'probe' for the correct dev->board_ptr.
+        */
        spin_lock_irqsave(&dev->spinlock, irq_flags);
        id_bits = das800_ind_read(dev, ID) & 0x3;
        spin_unlock_irqrestore(&dev->spinlock, irq_flags);
 
        switch (id_bits) {
        case 0x0:
-               if (board == BOARD_DAS800 || board == BOARD_CIODAS800)
-                       break;
-               dev_dbg(dev->class_dev, "Board model (probed): DAS-800\n");
-               board = BOARD_DAS800;
+               if (index == BOARD_DAS800 || index == BOARD_CIODAS800)
+                       return board;
+               index = BOARD_DAS800;
                break;
        case 0x2:
-               if (board == BOARD_DAS801 || board == BOARD_CIODAS801)
-                       break;
-               dev_dbg(dev->class_dev, "Board model (probed): DAS-801\n");
-               board = BOARD_DAS801;
+               if (index == BOARD_DAS801 || index == BOARD_CIODAS801)
+                       return board;
+               index = BOARD_DAS801;
                break;
        case 0x3:
-               if (board == BOARD_DAS802 || board == BOARD_CIODAS802 ||
-                   board == BOARD_CIODAS80216)
-                       break;
-               dev_dbg(dev->class_dev, "Board model (probed): DAS-802\n");
-               board = BOARD_DAS802;
+               if (index == BOARD_DAS802 || index == BOARD_CIODAS802 ||
+                   index == BOARD_CIODAS80216)
+                       return board;
+               index = BOARD_DAS802;
                break;
        default:
                dev_dbg(dev->class_dev, "Board model: 0x%x (unknown)\n",
                        id_bits);
-               board = -EINVAL;
-               break;
+               return NULL;
        }
-       return board;
+       dev_dbg(dev->class_dev, "Board model (probed): %s series\n",
+               das800_boards[index].name);
+
+       return &das800_boards[index];
 }
 
 static int das800_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 {
-       const struct das800_board *thisboard;
+       const struct das800_board *board;
        struct das800_private *devpriv;
        struct comedi_subdevice *s;
        unsigned int irq = it->options[1];
        unsigned long irq_flags;
-       int board;
        int ret;
 
        devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
@@ -663,13 +671,10 @@ static int das800_attach(struct comedi_device *dev, struct comedi_devconfig *it)
                return ret;
 
        board = das800_probe(dev);
-       if (board < 0) {
-               dev_dbg(dev->class_dev, "unable to determine board type\n");
+       if (!board)
                return -ENODEV;
-       }
-       dev->board_ptr = das800_boards + board;
-       thisboard = dev->board_ptr;
-       dev->board_name = thisboard->name;
+       dev->board_ptr = board;
+       dev->board_name = board->name;
 
        if (irq > 1 && irq <= 7) {
                ret = request_irq(irq, das800_interrupt, 0, dev->board_name,
@@ -693,8 +698,8 @@ static int das800_attach(struct comedi_device *dev, struct comedi_devconfig *it)
        s->type         = COMEDI_SUBD_AI;
        s->subdev_flags = SDF_READABLE | SDF_GROUND;
        s->n_chan       = 8;
-       s->maxdata      = (1 << thisboard->resolution) - 1;
-       s->range_table  = thisboard->ai_range;
+       s->maxdata      = (1 << board->resolution) - 1;
+       s->range_table  = board->ai_range;
        s->insn_read    = das800_ai_insn_read;
        if (dev->irq) {
                s->subdev_flags |= SDF_CMD_READ;