From 0ce8280e2876091b5c67cb515fae8e9bf3b50bfd Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Mon, 26 Jan 2015 16:17:16 -0700 Subject: [PATCH] staging: comedi: das16: introduce das16_ai_range() Clarify the (*attach) a bit by introducing a helper function to handle the setup of the analog input 'range_table'. Some of the boards supported by this driver do not have programmable ranges. The analog input subdevice can use optional range information provided by the user during the attach of the driver. Currently this range data is allocated and stored in the private data. Use the subdevice private data member instead and allocate the memory with comedi_alloc_spriv(). The comedi core will automatically free this memory when the driver is detached. If the allocation fails set the 'range_table' to 'range_unknown' instead of failing the driver attach. Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/das16.c | 63 ++++++++++++++++++++-------------- 1 file changed, 37 insertions(+), 26 deletions(-) diff --git a/drivers/staging/comedi/drivers/das16.c b/drivers/staging/comedi/drivers/das16.c index 2564af0..cb38e4b 100644 --- a/drivers/staging/comedi/drivers/das16.c +++ b/drivers/staging/comedi/drivers/das16.c @@ -443,7 +443,6 @@ struct das16_private_struct { unsigned long adc_byte_count; unsigned int divisor1; unsigned int divisor2; - struct comedi_lrange *user_ai_range_table; struct comedi_lrange *user_ao_range_table; struct timer_list timer; short timer_running; @@ -952,6 +951,42 @@ static void das16_free_dma(struct comedi_device *dev) } } +static const struct comedi_lrange *das16_ai_range(struct comedi_device *dev, + struct comedi_subdevice *s, + struct comedi_devconfig *it, + unsigned int pg_type, + unsigned int status) +{ + unsigned int min = it->options[4]; + unsigned int max = it->options[5]; + + /* get any user-defined input range */ + if (pg_type == das16_pg_none && (min || max)) { + struct comedi_lrange *lrange; + struct comedi_krange *krange; + + /* allocate single-range range table */ + lrange = comedi_alloc_spriv(s, + sizeof(*lrange) + sizeof(*krange)); + if (!lrange) + return &range_unknown; + + /* initialize ai range */ + lrange->length = 1; + krange = lrange->range; + krange->min = min; + krange->max = max; + krange->flags = UNIT_volt; + + return lrange; + } + + /* use software programmable range */ + if (status & DAS16_STATUS_UNIPOLAR) + return das16_ai_uni_lranges[pg_type]; + return das16_ai_bip_lranges[pg_type]; +} + static int das16_attach(struct comedi_device *dev, struct comedi_devconfig *it) { const struct das16_board *board = dev->board_ptr; @@ -1015,23 +1050,6 @@ static int das16_attach(struct comedi_device *dev, struct comedi_devconfig *it) das16_alloc_dma(dev, it->options[2]); - /* get any user-defined input range */ - if (board->ai_pg == das16_pg_none && - (it->options[4] || it->options[5])) { - /* allocate single-range range table */ - lrange = kzalloc(sizeof(*lrange) + sizeof(*krange), GFP_KERNEL); - if (!lrange) - return -ENOMEM; - - /* initialize ai range */ - devpriv->user_ai_range_table = lrange; - lrange->length = 1; - krange = devpriv->user_ai_range_table->range; - krange->min = it->options[4]; - krange->max = it->options[5]; - krange->flags = UNIT_volt; - } - /* get any user-defined output range */ if (it->options[6] || it->options[7]) { /* allocate single-range range table */ @@ -1067,13 +1085,7 @@ static int das16_attach(struct comedi_device *dev, struct comedi_devconfig *it) } s->len_chanlist = s->n_chan; s->maxdata = board->ai_maxdata; - if (devpriv->user_ai_range_table) { /* user defined ai range */ - s->range_table = devpriv->user_ai_range_table; - } else if (status & DAS16_STATUS_UNIPOLAR) { - s->range_table = das16_ai_uni_lranges[board->ai_pg]; - } else { - s->range_table = das16_ai_bip_lranges[board->ai_pg]; - } + s->range_table = das16_ai_range(dev, s, it, board->ai_pg, status); s->insn_read = das16_ai_insn_read; if (devpriv->dma) { dev->read_subdev = s; @@ -1153,7 +1165,6 @@ static void das16_detach(struct comedi_device *dev) if (dev->iobase) das16_reset(dev); das16_free_dma(dev); - kfree(devpriv->user_ai_range_table); kfree(devpriv->user_ao_range_table); if (devpriv->extra_iobase) -- 2.7.4