linux.git/drivers/staging/comedi/drivers.c, branch v3.12

Merge tag 'staging-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

2013-09-03T18:37:57+00:00

Pull staging tree merge from Greg KH:
 "Here's the bit staging tree pull request for 3.12-rc1.

  Lots of staging driver updates, and fixes.  Lustre is finally enabled
  in the build, and lots of cleanup started happening in it.  There's a
  new wireless driver in here, and 2 new TTY drivers, which cause the
  overall lines added/removed to be quite large on the "added" side.

  The IIO driver updates are also coming through here, as they are tied
  to the staging iio drivers"

* tag 'staging-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (942 commits)
  staging: dwc2: make dwc2_core_params documentation more complete
  staging: dwc2: validate the value for phy_utmi_width
  staging: dwc2: interpret all hwcfg and related register at init time
  staging: dwc2: properly mask the GRXFSIZ register
  staging: dwc2: remove redundant register reads
  staging: dwc2: re-use hptxfsiz variable
  staging: dwc2: simplify debug output in dwc_hc_init
  staging: dwc2: add missing shift
  staging: dwc2: simplify register shift expressions
  staging: dwc2: only read the snpsid register once
  staging: dwc2: unshift non-bool register value constants
  staging: dwc2: fix off-by-one in check for max_packet_count parameter
  staging: dwc2: remove specific fifo size constants
  Staging:BCM:DDRInit.c:Renaming __FUNCTION__
  staging: bcm: remove Version.h file.
  staging: rtl8188eu: off by one in rtw_set_802_11_add_wep()
  staging: r8188eu: copying one byte too much
  staging: rtl8188eu: || vs && typo
  staging: r8188eu: off by one bugs
  staging: crystalhd: Resolve sparse 'different base types' warnings.
  ...

staging: comedi: bug-fix NULL pointer dereference on failed attach

2013-08-23T17:31:47+00:00

Commit dcd7b8bd63cb81c5b973bf86510ca3c80bbbd162 ("staging: comedi: put
module _after_ detach" by myself) reversed a couple of calls in
`comedi_device_attach()` when recovering from an error returned by the
low-level driver's 'attach' handler.  Unfortunately, that introduced a
NULL pointer dereference bug as `dev->driver` is NULL after the call to
`comedi_device_detach()`.   We still have a pointer to the low-level
comedi driver structure in the `driv` variable, so use that instead.

Signed-off-by: Ian Abbott 
Cc:  # 3.10+
Signed-off-by: Greg Kroah-Hartman

staging: comedi: drivers: introduce comedi_dio_insn_config()

2013-08-12T22:17:45+00:00

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 
Reviewed-by: Ian Abbott 
Cc: Greg Kroah-Hartman 
Signed-off-by: Greg Kroah-Hartman

Revert "staging: comedi: core: introduce comedi_dio_insn_config()"

2013-08-12T22:16:24+00:00

This reverts commit 4f76463d3b8f8cc0cac5bb292ec766848f3f4fa1.

I applied an incorrect version here as well :(

Cc: H Hartley Sweeten 
Cc: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: core: introduce comedi_dio_insn_config()

2013-08-12T22:04:01+00:00

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 parameters 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 
Reviewed-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: use a mutex when accessing driver list

2013-07-23T21:22:29+00:00

Low-level comedi drivers registered with the comedi core by
`comedi_driver_register()` are linked together into a simple linked list
headed by the `comedi_drivers` variable and chained by the `next` member
of `struct comedi_driver`.  A driver is removed from the list by
`comedi_driver_unregister()`.  The driver list is iterated through by
`comedi_device_attach()` when the `COMEDI_DEVCONFIG` ioctl is used to
attach a "legacy" device to a driver, and is also iterated through by
`comedi_read()` in "proc.c" when reading "/proc/comedi".

There is currently no protection against items being added or removed
from the list while it is being iterated.  Add a mutex
`comedi_drivers_list_lock` to be locked while adding or removing an item
on the list, or when iterating through the list.

`comedi_driver_unregister()` also checks for and detaches any devices
using the driver.  This is currently done before unlinking the driver
from the list, but it makes more sense to unlink the driver from the
list first to prevent `comedi_device_attach()` attempting to use it, so
move the unlinking part to the start of the function.  Also, in
`comedi_device_attach()` hold on to the mutex until we've finished
attempting to attach the device to avoid it interfering with the
detachment in `comedi_driver_unregister()`.

Signed-off-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: return void from comedi_driver_unregister()

2013-07-23T21:22:29+00:00

'Unregister' functions generally return `void`.
`comedi_driver_unregister()` currently returns an `int` errno value.
Nothing looks at the return value.  Change the return type to `void`.

Signed-off-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: do not include if its not needed

2013-07-23T21:07:26+00:00

Some of the comedi files include this header but don't need it.

Signed-off-by: H Hartley Sweeten 
Cc: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: drivers: introduce comedi_alloc_devpriv()

2013-07-23T21:04:59+00:00

Introduce a helper function to allocate memory and set the
comedi_device private data pointer.

Signed-off-by: H Hartley Sweeten 
Reviewed-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: drivers: let core handle freeing s->private

2013-06-17T21:31:10+00:00

Introduce a new subdevice runflags, SRF_FREE_SPRIV, and a new helper
function, comedi_set_spriv(), that the drivers can use to set the
comedi_subdevice private data pointer. The helper function will also
set SRF_FREE_SPRIV to allow the comedi core to automatically free the
subdevice private data during the cleanup_device() stage of the detach.

Currently s->private is only allocated by the 8255, addi_watchdog,
amplc_dio200_common, and ni_65xx drivers. All users of those drivers
can then have the comedi_spriv_free() calls removed and in many cases
the (*detach) can then simply be the appropriate comedi core provided
function.

The ni_65xx driver uses a helper function, ni_65xx_alloc_subdevice_private(),
to allocate the private data. Refactor the function to return an errno
or call comedi_set_spriv() instead of returning a pointer to the private
data and requiring the caller to handle it.

Signed-off-by: H Hartley Sweeten 
Reviewed-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman