linux.git/drivers/staging/comedi/drivers.c, branch v3.11

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: 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

staging: comedi: ni_pcidio: use comedi_load_firmware()

2013-05-17T19:09:50+00:00

Use comedi_load_firmware() instead of duplicating the code in a
private function.

This driver loads multiple firmware images to the device. Modify
comedi_load_firmware() to take a 'context' that is passed to the
firmware upload callback function.

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

staging: comedi: drivers: generalize comedi_load_firmware()

2013-05-17T19:09:49+00:00

Move comedi_load_firmware() from jr3_pci.c to drivers.c and export
it for general use by the comedi drivers.

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

staging: comedi: remove FSF address from boilerplate text

2013-05-13T21:34:22+00:00

Addresses change...

Remove the paragraph with the FSF address from all the comedi source
files.

Also, remove the paragraph about the finding the complete GPL in the
COPYING file since it's unnecessary.

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

staging: comedi: drivers: free_irq() in comedi_legacy_detach()

2013-04-19T18:19:54+00:00

All the legacy comedi drivers now call comedi_legacy_detach()
either directly or as part of their (*detach). Move the free_irq()
into comedi_legacy_detach() so that the drivers don't have to
deal with it.

For drivers that then only call comedi_legacy_detach() in their
private (*detach), remove the private function and use the helper
directly for the (*detach).

The amplc_pc236 and ni_labpc drivers are hybrid legacy/PCI drivers.
In the detach of a PCI board free_irq() still needs to be handled
by the driver.

The pcl724 and pcl726 drivers currently have the free_irq() #ifdef'ed
out. The comedi_legacy_detach() function sanity checks that the irq
has been requested before freeing it so they are safe to convert.

For aesthetic reasons, move the #ifdef unused chunk in the pcl816
driver up to the previous #ifdef unused block.

The pcmio and pcmuio drivers request multiple irqs and handle the
freeing of them. Remove the 'dev->irq = irq[0]' in those drivers
so that comedi_legacy_detach() does not attempt to free the irq.

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

staging: comedi: drivers: introduce comedi_legacy_detach()

2013-04-19T18:19:52+00:00

This function is intended to be used by the comedi legacy (ISA) drivers
either directly as the (*detach) function or as a helper in the drivers
private (*detach) function.

Modify the comedi_request_region() helper so that it stores the 'len' of
the region as well as the 'start' after the region has been successfuly
allocated by request_region() in __comedi_request_region(). This region
will then be automatically released detach of the driver by the
comedi_legacy_detach() helper.

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

staging: comedi: introduce, and use, comedi_spriv_free()

2013-04-17T17:13:01+00:00

The comedi_subdevice 'private' variable is a void * that is available
for the subdevice to use in manner. It's common in comedi drivers for
the driver to allocate memory for a subdevice and store the pointer
to that memory in the 'private' variable. It's then the responsibility
of the driver to free that memory when the device is detached.

Due to how the attach/detach works in comedi, the drivers need to do
some sanity checking before they can free the allocated memory during
the detach.

Introduce a helper function, comedi_spriv_free(), to handle freeing
the private data allocated for a subdevice. This allows moving all the
sanity checks into the helper function and makes it safe to call
with any context. It also allows removing some of the boilerplate
code in the (*detach) functions.

Remove the subdev_8255_cleanup() export in the 8255 subdevice driver
as well as the addi_watchdog_cleanup() export in the addi_watchdog
driver and use the new helper instead.

The amplc_dio200_common driver uses a number of local helper functions
to free the private data for it's subdevices. Remove those as well and
use the new helper.

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

staging: comedi: use EXPORT_SYMBOL_GPL() for all exported symbols

2013-04-12T22:09:59+00:00

Comedi is licensed under GPL. Some if its exports are currently
EXPORT_SYMBOL() and others are EXPORT_SYMBOL_GPL(). Change them all
to EXPORT_SYMBOL_GPL() and see if anyone reports any fall out.

If any of the symbols "need" to be EXPORT_SYMBOL() they will be
addressed as needed.

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

staging: comedi: drivers: refactor comedi_request_region()

2013-04-11T19:47:53+00:00

Split comedi_request_region() into two helper functions.

__comedi_request_region()
Handles the actual request_region() call.

comedi_request_region()
Calls __comedi_request_region() and then sets dev->iobase if the
request was successful.

This allows drivers to use the __comedi_request_region() helper
to handle the request without setting the dev->iobase.

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