X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Fdrivers%2Fstaging%2Fcomedi%2Fdrivers%2Fdas1800.c;h=3be10963f98b6bd2296ee1972118fbd562091738;hb=52f993b8e89487ec9ee15a7fb4979e0f09a45b27;hp=53baf37cd21a6ab71e6eea8bb66a524e51f8e24e;hpb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;p=kvmfornfv.git

diff --git a/kernel/drivers/staging/comedi/drivers/das1800.c b/kernel/drivers/staging/comedi/drivers/das1800.c
index 53baf37cd..3be10963f 100644
--- a/kernel/drivers/staging/comedi/drivers/das1800.c
+++ b/kernel/drivers/staging/comedi/drivers/das1800.c
@@ -444,9 +444,9 @@ static const struct comedi_lrange range_ao_2 = {
 static inline uint16_t munge_bipolar_sample(const struct comedi_device *dev,
 					    uint16_t sample)
 {
-	const struct das1800_board *thisboard = dev->board_ptr;
+	const struct das1800_board *board = dev->board_ptr;
 
-	sample += 1 << (thisboard->resolution - 1);
+	sample += 1 << (board->resolution - 1);
 	return sample;
 }
 
@@ -567,14 +567,17 @@ static int das1800_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
 	struct comedi_isadma_desc *desc;
 	int i;
 
-	outb(0x0, dev->iobase + DAS1800_STATUS);	/* disable conversions */
-	outb(0x0, dev->iobase + DAS1800_CONTROL_B);	/* disable interrupts and dma */
-	outb(0x0, dev->iobase + DAS1800_CONTROL_A);	/* disable and clear fifo and stop triggering */
+	/* disable and stop conversions */
+	outb(0x0, dev->iobase + DAS1800_STATUS);
+	outb(0x0, dev->iobase + DAS1800_CONTROL_B);
+	outb(0x0, dev->iobase + DAS1800_CONTROL_A);
 
-	for (i = 0; i < 2; i++) {
-		desc = &dma->desc[i];
-		if (desc->chan)
-			comedi_isadma_disable(desc->chan);
+	if (dma) {
+		for (i = 0; i < 2; i++) {
+			desc = &dma->desc[i];
+			if (desc->chan)
+				comedi_isadma_disable(desc->chan);
+		}
 	}
 
 	return 0;
@@ -725,7 +728,7 @@ static int das1800_ai_do_cmdtest(struct comedi_device *dev,
 				 struct comedi_subdevice *s,
 				 struct comedi_cmd *cmd)
 {
-	const struct das1800_board *thisboard = dev->board_ptr;
+	const struct das1800_board *board = dev->board_ptr;
 	int err = 0;
 	unsigned int arg;
 
@@ -765,7 +768,7 @@ static int das1800_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);
@@ -934,13 +937,14 @@ static void das1800_ai_setup_dma(struct comedi_device *dev,
 {
 	struct das1800_private *devpriv = dev->private;
 	struct comedi_isadma *dma = devpriv->dma;
-	struct comedi_isadma_desc *desc = &dma->desc[0];
+	struct comedi_isadma_desc *desc;
 	unsigned int bytes;
 
 	if ((devpriv->irq_dma_bits & DMA_ENABLED) == 0)
 		return;
 
 	dma->cur_dma = 0;
+	desc = &dma->desc[0];
 
 	/* determine a dma transfer size to fill buffer in 0.3 sec */
 	bytes = das1800_ai_transfer_size(dev, s, desc->maxsize, 300000000);
@@ -1048,7 +1052,7 @@ static int das1800_ai_rinsn(struct comedi_device *dev,
 			    struct comedi_subdevice *s,
 			    struct comedi_insn *insn, unsigned int *data)
 {
-	const struct das1800_board *thisboard = dev->board_ptr;
+	const struct das1800_board *board = dev->board_ptr;
 	int i, n;
 	int chan, range, aref, chan_range;
 	int timeout = 1000;
@@ -1098,7 +1102,7 @@ static int das1800_ai_rinsn(struct comedi_device *dev,
 		dpnt = inw(dev->iobase + DAS1800_FIFO);
 		/* shift data to offset binary for bipolar ranges */
 		if ((conv_flags & UB) == 0)
-			dpnt += 1 << (thisboard->resolution - 1);
+			dpnt += 1 << (board->resolution - 1);
 		data[n] = dpnt;
 	}
 exit:
@@ -1112,16 +1116,16 @@ static int das1800_ao_winsn(struct comedi_device *dev,
 			    struct comedi_subdevice *s,
 			    struct comedi_insn *insn, unsigned int *data)
 {
-	const struct das1800_board *thisboard = dev->board_ptr;
+	const struct das1800_board *board = dev->board_ptr;
 	struct das1800_private *devpriv = dev->private;
 	int chan = CR_CHAN(insn->chanspec);
 /* int range = CR_RANGE(insn->chanspec); */
-	int update_chan = thisboard->ao_n_chan - 1;
+	int update_chan = board->ao_n_chan - 1;
 	unsigned short output;
 	unsigned long irq_flags;
 
 	/*   card expects two's complement data */
-	output = data[0] - (1 << (thisboard->resolution - 1));
+	output = data[0] - (1 << (board->resolution - 1));
 	/*  if the write is to the 'update' channel, we need to remember its value */
 	if (chan == update_chan)
 		devpriv->ao_update_bits = output;
@@ -1216,72 +1220,77 @@ static void das1800_free_dma(struct comedi_device *dev)
 		comedi_isadma_free(devpriv->dma);
 }
 
-static int das1800_probe(struct comedi_device *dev)
+static const struct das1800_board *das1800_probe(struct comedi_device *dev)
 {
 	const struct das1800_board *board = dev->board_ptr;
-	int index;
+	int index = board ? board - das1800_boards : -EINVAL;
 	int id;
 
-	/* calc the offset to the boardinfo that was found by the core */
-	index = board - das1800_boards;
-
-	/* verify that the board id matches the boardinfo */
+	/*
+	 * 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 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 is used
+	 * to 'probe' for the correct dev->board_ptr.
+	 */
 	id = (inb(dev->iobase + DAS1800_DIGITAL) >> 4) & 0xf;
 	switch (id) {
 	case 0x3:
 		if (index == das1801st_da || index == das1802st_da ||
 		    index == das1701st_da || index == das1702st_da)
-			return index;
+			return board;
 		index = das1801st;
 		break;
 	case 0x4:
 		if (index == das1802hr_da || index == das1702hr_da)
-			return index;
+			return board;
 		index = das1802hr;
 		break;
 	case 0x5:
 		if (index == das1801ao || index == das1802ao ||
 		    index == das1701ao || index == das1702ao)
-			return index;
+			return board;
 		index = das1801ao;
 		break;
 	case 0x6:
 		if (index == das1802hr || index == das1702hr)
-			return index;
+			return board;
 		index = das1802hr;
 		break;
 	case 0x7:
 		if (index == das1801st || index == das1802st ||
 		    index == das1701st || index == das1702st)
-			return index;
+			return board;
 		index = das1801st;
 		break;
 	case 0x8:
 		if (index == das1801hc || index == das1802hc)
-			return index;
+			return board;
 		index = das1801hc;
 		break;
 	default:
 		dev_err(dev->class_dev,
 			"Board model: probe returned 0x%x (unknown, please report)\n",
 			id);
-		break;
+		return NULL;
 	}
 	dev_err(dev->class_dev,
 		"Board model (probed, not recommended): %s series\n",
 		das1800_boards[index].name);
 
-	return index;
+	return &das1800_boards[index];
 }
 
 static int das1800_attach(struct comedi_device *dev,
 			  struct comedi_devconfig *it)
 {
-	const struct das1800_board *thisboard;
+	const struct das1800_board *board;
 	struct das1800_private *devpriv;
 	struct comedi_subdevice *s;
 	unsigned int irq = it->options[1];
-	int board;
 	int ret;
 
 	devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
@@ -1293,17 +1302,15 @@ static int das1800_attach(struct comedi_device *dev,
 		return ret;
 
 	board = das1800_probe(dev);
-	if (board < 0) {
+	if (!board) {
 		dev_err(dev->class_dev, "unable to determine board type\n");
 		return -ENODEV;
 	}
-
-	dev->board_ptr = das1800_boards + board;
-	thisboard = dev->board_ptr;
-	dev->board_name = thisboard->name;
+	dev->board_ptr = board;
+	dev->board_name = board->name;
 
 	/*  if it is an 'ao' board with fancy analog out then we need extra io ports */
-	if (thisboard->ao_ability == 2) {
+	if (board->ao_ability == 2) {
 		unsigned long iobase2 = dev->iobase + IOBASE2;
 
 		ret = __comedi_request_region(dev, iobase2, DAS1800_SIZE);
@@ -1363,11 +1370,11 @@ static int das1800_attach(struct comedi_device *dev,
 	s = &dev->subdevices[0];
 	s->type = COMEDI_SUBD_AI;
 	s->subdev_flags = SDF_READABLE | SDF_DIFF | SDF_GROUND;
-	if (thisboard->common)
+	if (board->common)
 		s->subdev_flags |= SDF_COMMON;
-	s->n_chan = thisboard->qram_len;
-	s->maxdata = (1 << thisboard->resolution) - 1;
-	s->range_table = thisboard->range_ai;
+	s->n_chan = board->qram_len;
+	s->maxdata = (1 << board->resolution) - 1;
+	s->range_table = board->range_ai;
 	s->insn_read = das1800_ai_rinsn;
 	if (dev->irq) {
 		dev->read_subdev = s;
@@ -1381,11 +1388,11 @@ static int das1800_attach(struct comedi_device *dev,
 
 	/* analog out */
 	s = &dev->subdevices[1];
-	if (thisboard->ao_ability == 1) {
+	if (board->ao_ability == 1) {
 		s->type = COMEDI_SUBD_AO;
 		s->subdev_flags = SDF_WRITABLE;
-		s->n_chan = thisboard->ao_n_chan;
-		s->maxdata = (1 << thisboard->resolution) - 1;
+		s->n_chan = board->ao_n_chan;
+		s->maxdata = (1 << board->resolution) - 1;
 		s->range_table = &range_bipolar10;
 		s->insn_write = das1800_ao_winsn;
 	} else {
@@ -1405,7 +1412,7 @@ static int das1800_attach(struct comedi_device *dev,
 	s = &dev->subdevices[3];
 	s->type = COMEDI_SUBD_DO;
 	s->subdev_flags = SDF_WRITABLE;
-	s->n_chan = thisboard->do_n_chan;
+	s->n_chan = board->do_n_chan;
 	s->maxdata = 1;
 	s->range_table = &range_digital;
 	s->insn_bits = das1800_do_wbits;
@@ -1416,9 +1423,9 @@ static int das1800_attach(struct comedi_device *dev,
 	outb(0, dev->iobase + DAS1800_DIGITAL);
 
 	/*  initialize analog out channels */
-	if (thisboard->ao_ability == 1) {
+	if (board->ao_ability == 1) {
 		/*  select 'update' dac channel for baseAddress + 0x0 */
-		outb(DAC(thisboard->ao_n_chan - 1),
+		outb(DAC(board->ao_n_chan - 1),
 		     dev->iobase + DAS1800_SELECT);
 		outw(devpriv->ao_update_bits, dev->iobase + DAS1800_DAC);
 	}