From a69153f66f3caef506a6a03a6f6ba76f75f57d29 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Thu, 18 Jun 2015 10:54:47 -0700 Subject: [PATCH] staging: comedi: das800: cleanup das800_probe() Make this function return a pointer to the boardinfo instead of an index. Since it's not typical, add a comment to clarify why this legacy driver does a probe. For aesthetics, rename the local variable 'board' to 'index. Consolidate the dev_dbg() messages when a probed boardinfo is used and remove the extra dev_dbg() message when the boardinfo is not found. Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/das800.c | 55 ++++++++++++++----------- 1 file changed, 30 insertions(+), 25 deletions(-) diff --git a/drivers/staging/comedi/drivers/das800.c b/drivers/staging/comedi/drivers/das800.c index 39d304a1259f..bc9fa4b317b2 100644 --- a/drivers/staging/comedi/drivers/das800.c +++ b/drivers/staging/comedi/drivers/das800.c @@ -604,44 +604,53 @@ 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; + int index = thisboard ? thisboard - 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 thisboard; + 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 thisboard; + 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 thisboard; + 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) @@ -651,7 +660,6 @@ static int das800_attach(struct comedi_device *dev, struct comedi_devconfig *it) 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)); @@ -662,13 +670,10 @@ static int das800_attach(struct comedi_device *dev, struct comedi_devconfig *it) if (ret) return ret; - board = das800_probe(dev); - if (board < 0) { - dev_dbg(dev->class_dev, "unable to determine board type\n"); + thisboard = das800_probe(dev); + if (!thisboard) return -ENODEV; - } - dev->board_ptr = das800_boards + board; - thisboard = dev->board_ptr; + dev->board_ptr = thisboard; dev->board_name = thisboard->name; if (irq > 1 && irq <= 7) { -- 2.39.5