diff options
| author | H Hartley Sweeten <hsweeten@visionengravers.com> | 2013-08-06 09:31:35 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-08-12 15:17:45 -0700 |
| commit | e523c6c86232eb5564662aa17199c676d127bc5e (patch) | |
| tree | 72644f8fbdb5fcf7eb4970ae7cb16fbc86d8c6c2 | |
| parent | 987f3c86a14a67d16bcc648d062bfa46cbd2e552 (diff) | |
staging: comedi: drivers: introduce comedi_dio_insn_config()
DIO subdevices always handle the INSN_CONFIG_DIO_{INPUT,OUTPUT} instructions
to configure the DIO channels. They also always handle the INSN_CONFIG_DIO_QUERY
instruction to query the configuration of a DIO channel.
Introduce a helper function to handle the (*insn_config) boilerplate for
comedi DIO subdevices. This function has the same paramters as (*insn_config)
functions with an additional parameter to allow the caller to pass a 'mask'
value for grouped DIO channels.
This function returns:
0 if the instruction was successful but requires additional handling by
the caller (INSN_CONFIG_DIO_{INPUT,OUTPUT}
insn->n if the instruction was handled (INSN_CONFIG_DIO_QUERY)
-EINVAL for all unhandled instructions
The caller is responsible for actually configuring the hardware based on
the configuration (s->io_bits).
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/staging/comedi/comedidev.h | 4 | ||||
| -rw-r--r-- | drivers/staging/comedi/drivers.c | 40 |
2 files changed, 44 insertions, 0 deletions
diff --git a/drivers/staging/comedi/comedidev.h b/drivers/staging/comedi/comedidev.h index 98058b9097e..f2f75b9dfb8 100644 --- a/drivers/staging/comedi/comedidev.h +++ b/drivers/staging/comedi/comedidev.h @@ -342,6 +342,10 @@ void comedi_buf_memcpy_from(struct comedi_async *async, unsigned int offset, /* drivers.c - general comedi driver functions */ +int comedi_dio_insn_config(struct comedi_device *, struct comedi_subdevice *, + struct comedi_insn *, unsigned int *data, + unsigned int mask); + void *comedi_alloc_devpriv(struct comedi_device *, size_t); int comedi_alloc_subdevices(struct comedi_device *, int); diff --git a/drivers/staging/comedi/drivers.c b/drivers/staging/comedi/drivers.c index 791a26bd5f6..60fd81c71a1 100644 --- a/drivers/staging/comedi/drivers.c +++ b/drivers/staging/comedi/drivers.c @@ -150,6 +150,46 @@ int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s, return -EINVAL; } +/** + * comedi_dio_insn_config() - boilerplate (*insn_config) for DIO subdevices. + * @dev: comedi_device struct + * @s: comedi_subdevice struct + * @insn: comedi_insn struct + * @data: parameters for the @insn + * @mask: io_bits mask for grouped channels + */ +int comedi_dio_insn_config(struct comedi_device *dev, + struct comedi_subdevice *s, + struct comedi_insn *insn, + unsigned int *data, + unsigned int mask) +{ + unsigned int chan_mask = 1 << CR_CHAN(insn->chanspec); + + if (!mask) + mask = chan_mask; + + switch (data[0]) { + case INSN_CONFIG_DIO_INPUT: + s->io_bits &= ~mask; + break; + + case INSN_CONFIG_DIO_OUTPUT: + s->io_bits |= mask; + break; + + case INSN_CONFIG_DIO_QUERY: + data[1] = (s->io_bits & mask) ? COMEDI_OUTPUT : COMEDI_INPUT; + return insn->n; + + default: + return -EINVAL; + } + + return 0; +} +EXPORT_SYMBOL_GPL(comedi_dio_insn_config); + static int insn_rw_emulate_bits(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_insn *insn, unsigned int *data) |