Ian Abbott [Thu, 4 Apr 2013 13:59:18 +0000 (14:59 +0100)]
staging: comedi: add comedi_clear_board_dev()
Add local function `comedi_clear_board_dev()` as a safer alternative to
`comedi_clear_board_minor()` when we already have a pointer to a `struct
comedi_device`. It uses the board minor device number stored in the
`struct comedi_device` (which must have already been initialized) and
only clears the entry in `comedi_board_minor_table[]` if it points to
the specified `struct comedi_device`. Rather than returning the old
table entry, it returns `true` if the entry matched (and so has just
been cleared) and returns `false` otherwise.
Call `comedi_clear_board_dev()` instead of `comedi_clear_board_minor()`
in `comedi_unlocked_ioctl()` (in the code that frees a dynamically
allocated comedi device detached by the `COMEDI_DEVCONFIG` ioctl). That
ought to return `true` but check it just in case before freeing the
device. There is still a race condition here which needs to be dealt
with once we've implemented reference counting for `struct
comedi_device`s.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
`comedi_alloc_board_minor()` allocates and initializes a `struct
comedi_file_info` and a `struct comedi_device`, and assigns a board
minor device number (if there are any available), storing a pointer to
the allocated `struct comedi_file_info` in
`comedi_board_minor_table[minor]` where `minor` is the board minor
device number.
There is no longer anything useful in the `struct comedi_file_info`
apart from the pointer to the `struct comedi_device` that was allocated,
so the `struct comedi_file_info` is superfluous.
Change `comedi_board_minor_table[]` to hold pointers to the actual
`struct comedi_device`'s. `comedi_alloc_board_minor()` no longer needs
to allocate a `struct comedi_file_info`. Replace
`comedi_free_board_file_info()` with `comedi_free_board_dev()` with its
parameter pointing to the `struct comedi_device` to be freed (there is
no longer a `struct comedi_file_info` to be freed).
There are consequential changes to `comedi_dev_from_board_minor()`,
`comedi_clear_board_minor()` (which now returns a `struct comedi_device
*`), `comedi_free_board_minor()`, `comedi_release_hardware_device()` and
`comedi_unlocked_ioctl()` (when dealing with detachment of a dynamically
allocated comedi device by the `COMEDI_DEVCONFIG` ioctl).
`comedi_dev_from_file_info()` is no longer used as a result of the above
changes so remove it.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
`comedi_alloc_subdevice_minor()` allocates and initializes a `struct
comedi_file_info` and assigns a subdevice minor device number (if there
are any available), storing a pointer to the allocated `struct
comedi_file_info` in `comedi_subdevice_minor_table[i]` where `i` is the
array index corresponding to the subdevice minor device number (indexed
by subdevice minor device number minus `COMEDI_NUM_BOARD_MINORS`).
The information stored in the `struct comedi_file_info` can be derived
from the subdevice structure (`struct comedi_subdevice`) itself, so the
`struct comedi_file_info` is superfluous.
Change `comedi_subdevice_minor_table[]` to hold pointers to the actual
`struct comedi_subdevice`'s. `comedi_alloc_subdevice_minor()` no longer
needs to allocate a `struct comedi_file_info` and
`comedi_free_subdevice_info()` no longer has a `struct comedi_file_info`
to free.
Replace `comedi_file_info_from_minor()` with
`comedi_subdevice_from_minor()`, returning a (possibly NULL) pointer to
a `struct comedi_subdevice` from the table. This has knock-on effects
for `comedi_dev_from_subdevice_minor()`, `comedi_read_subdevice()` and
`comedi_write_subdevice()`. In particular, `comedi_read_subdevice()`
and `comedi_write_subdevice()` now need to check the subdevice flags to
see if the determine whether to override the comedi device's default
read/write subdevice.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:59:12 +0000 (14:59 +0100)]
staging: comedi: refactor comedi_dev_from_minor()
Refactor `comedi_dev_from_minor()` to call one of two new functions
`comedi_dev_from_board_minor()` (for minor device numbers less than
`COMEDI_NUM_BOARD_MINORS`) or `comedi_dev_from_subdevice_minor()` (for
minor device numbers greater than or equal to `COMEDI_NUM_BOARD_MINORS`,
which are subdevice minor device numbers).
Remove `comedi_file_info_from_minor()` as it is no longer used.
This is a step towards removing `struct comedi_file_info`.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:59:11 +0000 (14:59 +0100)]
staging: comedi: reduce use of struct comedi_file_info
Since the parameters of `comedi_read_subdevice()` and
`comedi_write_subdevice()` have changed, there is no longer a need to
keep a local variable `struct comedi_file_info *info` hanging around in
the file operation functions and device attribute access functions.
Remove the variable from those function and replace the call sequence
`info = comedi_file_info_from_minor(minor)`, `dev =
comedi_dev_from_file_info(info)` with the simpler `dev =
comedi_dev_from_minor(minor)`.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
`comedi_read_subdevice()` and `comedi_write_subdevice()` currently take
a single parameter pointing to a `struct comedi_file_info`. I'm trying
to get rid of `struct comedi_file_info` so as part of that plan,
`comedi_read_subdevice()` and `comedi_write_subdevice()` need to change.
Change them to take two parameters: a pointer to a `struct
comedi_device` and a minor device number. If the minor device number is
a "board" minor device number (`minor < COMEDI_NUM_BOARD_MINORS`) we'll
always return the default read or write subdevice. If the minor device
number if a "subdevice" minor device number a different read or write
subdevice may be returned. In that case, use the subdevice minor device
number to look up the information about whether the default read or
write subdevice needs to be overridden.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:59:09 +0000 (14:59 +0100)]
staging: comedi: use minor device number in attribute functions
The comedi device attribute functions such as
`show_max_read_buffer_kb()` call `dev_get_drvdata()` to get a pointer to
a `struct comedi_file_info` from the private driver data field of class
device. Change them to use the minor device number to look up this
pointer value so they behave more like the file operation functions.
Check the pointer is non-NULL as the entry in the minor device table
could have been set to NULL. Note that there is still a race condition
in the use of this pointer value after acquiring the mutex which needs
to be dealt with once reference counting has been implemented for comedi
devices.
The calls to `dev_set_drvdata()` from `comedi_alloc_board_minor()` and
`comedi_alloc_subdevice_minor()` are no longer needed so remove them.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:59:08 +0000 (14:59 +0100)]
staging: comedi: get mutex before subdevice in attribute functions
The comedi device attribute functions such as
`show_read_buffer_kb()` or `show_write_buffer_kb()` call
`comedi_read_subdevice()` or `comedi_write_subdevice()` without
acquiring the comedi device's mutex first, although the functions do
acquire the mutex afterwards. Change them to acquire the mutex first.
This is consistent with most of the comedi device file operation
functions (apart from `comedi_read()` and `comedi_write()` which
probably need looking at).
Despite the use of the mutex, there are still race conditions as the
`struct comedi_file_info *info` variable value set before acquiring the
mutex could be stale after acquiring the mutex. This problem will be
dealt with once reference counting has been implemented for the comedi
devices.
This patch also adds local variable `struct comedi_device *dev` to the
functions to reduce the use of the `info` variable a little bit.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:59:07 +0000 (14:59 +0100)]
staging: comedi: rename dev parameter of device attribute functions
Most of the comedi core uses the identifier `dev` to point to a `struct
comedi_device`. The device sysfs attribute functions such as
`show_max_read_buffer_kb()` use the parameter id `dev` to point to a
`struct device`. Rename the parameter to `csdev` for "class device" for
consistency with the functions that call `device_create()` to create
these class devices (`comedi_alloc_board_minor()` and
`comedi_alloc_subdevice_minor()`).
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:59:06 +0000 (14:59 +0100)]
staging: comedi: remove hardware_device from struct comedi_device_info
The `hardware_device` member of `struct comedi_device_info` is only set
to point to a hardware device by the auto-configuration code (specifically
`comedi_alloc_board_minor() with a non-NULL `hardware_device` parameter)
so that it can be found again by the auto-unconfiguration code
(specifically `comedi_release_hardware_device()`). However, as
`info->device->hw_dev` (where `info` is a pointer to the `struct
comedi_device_info`) is set to the same value as `info->hardware_device`
(by calling `comedi_set_hw_dev()` with the same hardware device pointer)
we can look for that instead, so there is no need for the
`hardware_device` member any more. Get rid of it.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:59:05 +0000 (14:59 +0100)]
staging: comedi: remove comedi_clear_minor()
`comedi_clear_minor()` calls either `comedi_clear_board_minor()` or
`comedi_clear_subdevice_minor()` depending on its minor device number
parameter. The one it calls only depends on where it is called from, so
bypass the calls to `comedi_clear_minor()` and remove it.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:59:04 +0000 (14:59 +0100)]
staging: comedi: separate board and subdevice minor tables
The comedi core reserves minor device numbers from 0 to
`COMEDI_NUM_BOARD_MINORS - 1` (0 to 0x30 - 1) for the main comedi
"board" devices and reserves minor device numbers from
`COMEDI_NUM_BOARD_MINORS` to `COMEDI_NUM_MINORS - 1` (0x30 to 0x100 - 1)
for comedi subdevices (or at least those that claim to support
asynchronous comedi commands). There is an array
`comedi_file_info_table[COMEDI_NUM_MINORS]` used to hold pointers to
information for each board minor device number and subdevice minor
device number that has been allocated (with NULL pointers for those not
allocated), along with a protective lock `comedi_file_info_table_lock`.
Since the ranges of board minor device numbers and subdevice minor
device numbers do not overlap, we can use separate tables and separate
locks for the different types of minor device numbers. This will allow
us to use different pointer types for the elements of each table in the
future without just using a generic `void *`. (At the moment, the table
elements point to a `struct comedi_file_info` allocated dynamically for
each allocated board minor device or subdevice minor device, but I plan
to get rid of that data structure.)
Replace `comedi_file_info_table[COMEDI_NUM_MINORS]` with two new arrays
of the same type, `comedi_board_minor_table[COMEDI_NUM_BOARD_MINORS]`
for board minors, and
`comedi_subdevice_minor_table[COMEDI_NUM_SUBDEVICE_MINORS]` for
subdevice minors (where `COMEDI_NUM_SUBDEVICE_MINORS` is
`COMEDI_NUM_MINORS - COMEDI_NUM_BOARD_MINORS`).
`comedi_subdevice_minor_table[]` is indexed by the subdevice minor
number minus `COMEDI_NUM_BOARD_MINORS` since `COMEDI_NUM_BOARD_MINORS`
is the first valid subdevice minor number.
Replace `comedi_file_info_table_lock` with
`comedi_board_minor_table_lock` for board minors and
`comedi_subdevice_minor_table_lock` for subdevice minors.
Refactor `comedi_clear_minor()` to call one of two new functions
`comedi_clear_board_minor()` and `comedi_clear_subdevice_minor()`
depending on the minor device number passed as a parameter. Similarly,
refactor `comedi_file_info_from_minor()` to call one of two new
functions `comedi_file_info_from_board_minor()` and
`comedi_file_info_from_subdevice_minor()` depending on the minor device
number parameter.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The macro `COMEDI_FIRST_SUBDEVICE_MINOR` just expands to another macro
`COMEDI_NUM_BOARD_MINORS`. Replace uses of
`COMEDI_FIRST_SUBDEVICE_MINOR` with `COMEDI_NUM_BOARD_MINORS` and get
rid of the former.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:59:02 +0000 (14:59 +0100)]
staging: comedi: move COMEDI_NUM_MINORS and COMEDI_FIRST_SUBDEVICE_MINOR
The macro definitions `COMEDI_NUM_MINORS` and
`COMEDI_FIRST_SUBDEVICE_MINOR` are only used in "comedi_fops.c" so move
them to there from "comedidev.h".
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:59:01 +0000 (14:59 +0100)]
staging: comedi: change comedi_file_info_table_lock to mutex
The spin-lock `comedi_file_info_table_lock` is used to protect against
simultaneous modification and access of `comedi_file_info_table[]`.
Change it from a spin-lock to a mutex as it is only used in contexts
where sleeping is allowed.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:59:00 +0000 (14:59 +0100)]
staging: comedi: set hw_dev in comedi_alloc_board_minor()
Call `comedi_set_hw_dev()` to set the `hw_dev` member of `struct
comedi_device` in `comedi_alloc_board_minor()` instead of in
`comedi_auto_config()`. Don't bother to check for an error returned by
`comedi_set_hw_dev()` here; it only fails when changing a non-NULL
pointer to a different non-NULL pointer and since the `struct
comedi_device` has just been allocated and initialized, its `hw_dev`
will be NULL already. Calling `comedi_set_hw_dev()` with a non-NULL
hardware device pointer increments the kref counter for the hardware
device.
If `comedi_alloc_board_minor()` fails further down the function, we rely
on its call to `comedi_device_cleanup()` to call `comedi_clear_hw_dev()`
(via `comedi_device_detach()` and `cleanup_device()`) to clear `hw_dev`
and decrement its kref counter. (That's the "beneficial side-effect"
mentioned in the patch that replaced `__comedi_device_detach()`.)
Remove the call to `comedi_set_hw_dev()` from `comedi_auto_config()` as
the call to `comedi_alloc_board_minor()` does it for us.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:58:59 +0000 (14:58 +0100)]
staging: comedi: move detach out of post-config
`comedi_device_postconfig()` calls `comedi_device_detach()` on failure.
Remove that call and make the callers of `comedi_device_postconfig()`
call `comedi_device_detach()` themselves if it returns an error. This
seems more logical as the callers of `comedi_device_postconfig()` called
`comedi_device_detach()` anyway if they didn't call
`comedi_device_postconfig()`.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:58:58 +0000 (14:58 +0100)]
staging: comedi: replace __comedi_device_detach()
`comedi_device_detach()` does nothing if the `struct comedi_device`'s
`attached` member is false, otherwise it calls
`__comedi_device_detach()` to do the real work.
`__comedi_device_detach()` is called from various other functions in
"drivers.c" (`comedi_device_postconfig()`, `comedi_device_attach()`, and
`comedi_auto_config()`) to bypass the check for the `attached` member
being false.
If we make `__comedi_device_detach()` safe to call when the `attached`
member is already false, we can remove the check in
`comedi_device_detach()`, subsume `__comedi_device_detach()` within
`comedi_device_detach()`, and replace all the calls to
`__comedi_device_detach()` with calls to `comedi_device_detach()`.
In fact, it is already safe to call `__comedi_device_detach()` when the
`attached` member is false. We just need to remove the warning message
it outputs when the `driver` member is NULL. Then the function becomes
idempotent without outputting spurious warnings. (It is idempotent
because `dev->driver->detach()` will only be called once at most and the
call to `cleanup_device()` is idempotent itself.)
Combine `comedi_device_detach()` with `__comedi_device_detach()`,
removing the check for the `attached` member being false and removing
the warning about the `driver` member being NULL, and replace all calls
to `__comedi_device_detach()` with calls to the combined
`comedi_device_detach()`.
A beneficial side-effect of the above change is that a call to
`comedi_device_detach()` will always result in a call to
`cleanup_device()` and so always result in a call to
`comedi_clear_hw_dev()`. We will make use of this beneficial
side-effect in a later patch.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:58:57 +0000 (14:58 +0100)]
staging: comedi: put module _after_ detach
On failure of the call to the low-level comedi device driver's
`->attach()` handler from `__comedi_device_attach()`, reverse the
current ordering of the calls to `module_put()` and
`comedi_device_detach()` because `__comedi_device_detach()` will call
code in the module being put.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:58:56 +0000 (14:58 +0100)]
staging: comedi: simplify driver module counting
For a legacy device attachment with the `COMEDI_DEVCONFIG` ioctl,
`do_devconfig_ioctl()` calls `comedi_device_attach()` to find a matching
device driver and attach the device. It then tries to increment the
device driver's module count and if that fails it detaches the device.
So on successful attachment of a device by the `COMEDI_DEVCONFIG` ioctl,
the device driver's module count will have been incremented.
`comedi_device_attach()` is called from nowhere else. It already
increments the device driver's module count temporarily and decrements
it again; if it gets as far as calling `comedi_device_postconfig()` the
module count is decremented within that function.
Simplify the above by removing the decrement of the device driver module
count from `comedi_device_postconfig()`. If the call to
`comedi_device_postconfig()` succeeds, `comedi_device_attach()` will
return with the module count still incremented, otherwise decrement the
module count before returning the error. Don't try and increment the
module count in `do_devconfig_ioctl()` after a successful return from
`comedi_device_attach()` as the module count has now already been
incremented.
`comedi_device_postconfig()` is also called by `comedi_auto_config()`
which currently has to increment the device driver's module count
temporarily so that `comedi_device_postconfig()` can decrement it, but
always returns with no overall change to the module count. Remove all
the module count manipulations from `comedi_device_postconfig()`. There
is no other reason for `comedi_auto_config()` to increment the device
driver's module count temporarily, since it is only called (indirectly)
from the device driver itself (usually via one of the wrappers
`comedi_pci_auto_config()` or `comedi_usb_auto_config()`).
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a dynamically allocated (non-legacy, and automatically configured)
comedi device has been successfully unconfigured by use of the
`COMEDI_DEVCONFIG` ioctl, then remove the device afterwards.
(Dynamically identified comedi devices are identified by their minor
device number being `comedi_num_legacy_minors` or greater.) This is
done in `comedi_unlocked_ioctl()` on return from `do_devconfig_ioctl()`.
Note that there is an unlikely race condition with some other thread
that has just called `comedi_file_info_from_minor()` or
`comedi_dev_from_minor()` and is about to use the device, but that race
condition also exists for automatically removed devices and will be
dealt with properly once reference counting of comedi devices has been
implemented. We do avoid a race condition between automatic removal and
removal by the `COMEDI_DEVCONFIG` ioctl though.
Also add an extra precaution in `do_devconfig_ioctl()` to avoid
configuring a dynamically allocated device since there is a tight
window avoiding the race condition where this could happen and the
device is about to be removed anyway.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:58:53 +0000 (14:58 +0100)]
staging: comedi: no need to evade comedi_auto_unconfig()
When `comedi_unlocked_ioctl()` handled the `COMEDI_DEVCONFIG` ioctl via
a call to `do_devconfig()`, this used to be allowed to attach a legacy
hardware device to any board minor device, and the auto-unconfiguration
code for non-legacy used to search all board minor devices to find the
hardware device being removed. After calling `do_devconfig()`
successfully, `comedi_unlocked_ioctl()` sets the `hardware_device`
member of the `struct comedi_file_info` to NULL to stop the
auto-unconfiguration code finding it by accident and unconfiguring the
wrong comedi device as a result.
The above is no longer necessary because `do_devconfig()` now only
allows legacy hardware devices to be attached to comedi board minor
device numbers below `comedi_num_legacy_minors` and the
auto-unconfiguration code (particularly
`comedi_release_hardware_device()`) only searches comedi board minor
device numbers greater than or equal to `comedi_num_legacy_minors`, so
there is no overlap.
Remove the now unnecessary setting of `info->hardware_device = NULL` in
`comedi_unlocked_ioctl()`.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
`comedi_alloc_board_minor()` is called for both reserved "legacy"
devices created during module initialization, and for dynamically
created devices (via `comedi_auto_config()`). All the minor device
numbers from 0 to `comedi_num_legacy_minors - 1` are for legacy devices
and all those from `comedi_num_legacy_minors` to
`COMEDI_NUM_BOARD_MINORS - 1` are for dynamically created devices.
`comedi_release_hardware_device()` is called (via
`comedi_auto_unconfig()`) when a dynamically created device is being
removed. It needs to search the table of minor device numbers to see
which one is associated with the hardware device. It currently starts
the search at minor device number 0. Change it to start from
`comedi_num_legacy_minors` to skip over those belonging to legacy
devices. Also change `comedi_alloc_board_minor()` to skip the legacy
devices when searching for a free minor device number for the
dynamically created device. (The validity of the `hardware_device`
parameter is used to distinguish the legacy devices from the dynamically
created ones.)
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:58:51 +0000 (14:58 +0100)]
staging: comedi: pre-lock mutex on creation of comedi device
Return from `comedi_alloc_board_minor()` with the mutex of the created
`struct comedi_device` pre-locked. This allows further initialization
by the caller without the worry of something getting in there first.
`comedi_auto_config()` no longer needs to check if the device is already
"attached" since whatever was trying to attach the device would need to
have locked the mutex first.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:58:50 +0000 (14:58 +0100)]
staging: comedi: change comedi_alloc_board_minor() to return pointer
Change `comedi_alloc_board_minor()` to return a pointer to the allocated
`struct comedi_device` instead of a minor device number. Return an
`ERR_PTR()` value on error instead of a negative error number. This
saves a call to `comedi_dev_from_minor()` in `comedi_auto_config()`.
Also change it to use a local variable `dev` to hold the pointer to the
`struct comedi_device` instead of using `info->device` all the time.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:58:48 +0000 (14:58 +0100)]
staging: comedi: call comedi_release_hardware_device() on error
If `comedi_auto_config()` fails after allocating the minor device, call
`comedi_release_hardware_device()` instead of
`comedi_free_board_minor()` to free the minor device. That's the same
call that `comedi_auto_unconfig()` uses, and is slightly safer as it
checks the minor device number is still tied to the same hardware
device.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add `comedi_release_hardware_device()` as a replacement for the call
sequence `comedi_find_board_minor()`, `comedi_free_board_minor()`. This
is slightly safer as we can make sure nothing funny happens to the found
`comedi_file_info_table[]` entry in the middle of the sequence. Change
`comedi_auto_unconfig()` to call the new function instead of the old
sequence. Remove `comedi_find_board_minor()` as it has no other
callers.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Split out the part of `comedi_free_board_minor()` that clears the
`comedi_file_info_table[]` element into new function
`comedi_clear_minor()`. Split out the remainder of the original
function into new function `comedi_free_board_file_info()`.
Also re-use a call to `comedi_clear_minor()` in
`comedi_free_subdevice_minor()` instead of doing the same thing inline.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:58:45 +0000 (14:58 +0100)]
staging: comedi: adjust module count on device cleanup
`comedi_device_cleanup()` is called just before freeing a comedi device.
It is possible for the device to still be open in which case the module
reference counts for the core comedi module and possibly the low-level
driver module will remain out of whack because `comedi_close()` will not
find the comedi device and so will not decrement the module counts.
This really needs to be handled better, but for now decrement the module
counts in `comedi_device_cleanup()` according to the number of
outstanding opens.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:58:44 +0000 (14:58 +0100)]
staging: comedi: remove memset() call from comedi_device_init()
`comedi_device_init()` is only called from one place
(`comedi_alloc_board_minor()`) and the `struct comedi_device` has
already been zeroed out by `kzalloc()`. Don't bother zeroing it out
again with `memset()`.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ian Abbott [Thu, 4 Apr 2013 13:58:43 +0000 (14:58 +0100)]
staging: comedi: no need to zero out comedi_file_info_table[]
In the comedi core module, `comedi_file_info_table[]` is tentatively
defined in the .bss section, so will already be zeroed out on
initialization. Don't bother zeroing it out again in the module
initialization function `comedi_init()`.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
staging: dgrp: implement error handling in dgrp_create_class_sysfs_files()
There is no any error handling in dgrp_create_class_sysfs_files().
The patch adds code to check return values and propagate them to dgrp_init_module().
Found by Linux Driver Verification project (linuxtesting.org).
Kurt Kanzenbach [Thu, 4 Apr 2013 14:03:16 +0000 (16:03 +0200)]
staging: usbip: userspace: show product name in `list -l' command
The `usbip list -l' command shows your local usb-devices.
Example:
$ usbip list -l
$ Local USB devices
$ =================
$ - busid 1-1 (13fe:1d00)
$ 1-1:1.0 -> usb-storage
$
$ - busid 1-2 (0409:55aa)
$ 1-2:1.0 -> hub
However this list command doesn't show which device is connected
to this busid. Therefore you have to use another tool e.g. lsusb
to determine that.
This patches adds the possibility to see which device that is.
Example:
$ usbip list -l
$ Local USB devices
$ =================
$ - busid 1-1 (13fe:1d00)
$ Kingston Technology Company Inc. : DataTraveler 2.0 1GB/4GB Flash Drive / Patriot Xporter 4GB Flash
$ 1-1:1.0 -> usb-storage
$
$ - busid 1-2 (0409:55aa)
$ NEC Corp. : Hub (0409:55aa)
$ 1-2:1.0 -> hub
If parsable is specified the info will be not printed.
Signed-off-by: Kurt Kanzenbach <ly80toro@cip.cs.fau.de> Signed-off-by: Stefan Reif <ke42caxa@cip.cs.fau.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Kurt Kanzenbach [Thu, 4 Apr 2013 14:03:15 +0000 (16:03 +0200)]
staging: usbip: userspace: unified command line arguments
The command `usbip attach' uses --host for specifing
the remote host, while `usbip list' uses --remote.
This is confusing and this patch adapts this.
In Addition changed the manpage and README accordingly.
Since the names.c/names.h are taken from another project, some
functions which names.c provides aren't used by usbipd.
This patch fixes:
- removed useless comments
- unified debug/error messages by using the macros
provided by usbip_common.h
- removed unnused code
The code cleanup includes:
- remove unused data structures
- remove code to create them
- remove code to access them
The file names.c is used to parse the `usb.ids' file. The parser
stores a lot of information about usb devices that is never used.
The `usb.ids' file has several sections. Some variables (like
`lasthut') store the ID of the current section, and those variables
are used to decide which section is currently being parsed (i.e. in
which data structure the current line will be stored).
We removed the code to read those IDs because they are never used
anyway. We replaced them by the pseudo-ID `1' (instead of reading the
ID from the file) to indicate that the parser is in a section that
can be ignored. If the parser is in such a section, the current line
(which contains sub-items for this section) is discarded.
Signed-off-by: Kurt Kanzenbach <ly80toro@cip.cs.fau.de> Signed-off-by: Stefan Reif <ke42caxa@cip.cs.fau.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Kurt Kanzenbach [Thu, 4 Apr 2013 14:03:11 +0000 (16:03 +0200)]
staging: usbip: simplified cleanup function
This patch simplified "stub_device_free" cleanup function:
- changed return type to void, since the return value is
not checked anywhere
- kfree is NULL-safe, so removed if statement
- deleted debug-message
Signed-off-by: Kurt Kanzenbach <ly80toro@cip.cs.fau.de> Signed-off-by: Stefan Reif <ke42caxa@cip.cs.fau.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Kurt Kanzenbach [Thu, 4 Apr 2013 14:03:08 +0000 (16:03 +0200)]
staging: usbip: simplified errorhandling
In each errorcase spin_unlock_irq is called and -EINVAL is returned.
To simplify that I created a label called "err" doing that.
On Success count will be returned.
Signed-off-by: Kurt Kanzenbach <ly80toro@cip.cs.fau.de> Signed-off-by: Stefan Reif <ke42caxa@cip.cs.fau.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stefan Reif [Thu, 4 Apr 2013 14:03:02 +0000 (16:03 +0200)]
staging: usbip: userspace: libsrc: replace numbers by ascii
replace numbers in code by ascii text constants as suggested
by Dan Carpenter:
http://driverdev.linuxdriverproject.org/pipermail/devel/2013-February/035907.html
Signed-off-by: Stefan Reif <ke42caxa@cip.cs.fau.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Dan Carpenter [Thu, 4 Apr 2013 06:31:24 +0000 (09:31 +0300)]
staging: csr: info leak in unifi_cfg_get_info()
"cfg_ap_config" has a number of fields which are not cleared before we
copy them to the user. I've added a memset() at the beginning to set
everything to zero.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Rename the CamelCase struct rtdBoard to rtd_boardinfo. Also, rename the
range10Start and rangeUniStart variables in the struct to range_bip10
and range_uni10.
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>
Add a local variable to make this function a bit cleaner and
remove the unnecessary comments.
The comedi core expects this function to return the number of
data parameters used. Change the return from '1' to 'insn->n'
to make this more apparent.
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>
Wanpeng Li [Wed, 3 Apr 2013 10:16:21 +0000 (18:16 +0800)]
staging: zcache: fix static variables defined in debug.h but used in mutiple C files
After commit 95bdaee214 ("zcache: Move debugfs code out of zcache-main.c file")
be merged, most of knods in zcache debugfs just export zero since these variables
are defined in debug.h but are in use in multiple C files zcache-main.c and debug.c,
in this case variables can't be treated as shared variables.
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Wanpeng Li [Tue, 2 Apr 2013 02:46:17 +0000 (10:46 +0800)]
staging: zcache: fix zcache writeback in debugfs
commit 9c0ad59ef ("zcache/debug: Use an array to initialize/use debugfs attributes")
use an array to initialize/use debugfs attributes, .name = #x, .val = &zcache_##x.
For zcache writeback, this commit set .name = zcache_outstanding_writeback_pages and
.name = zcache_writtenback_pages seperately, however, corresponding .val =
&zcache_zcache_outstanding_writeback_pages and .val = &zcache_zcache_writtenback_pages,
which are not correct.
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Wanpeng Li [Tue, 2 Apr 2013 02:46:16 +0000 (10:46 +0800)]
staging: zcache: fix pers_pageframes|_max aren't exported in debugfs
Before commit 9c0ad59ef ("zcache/debug: Use an array to initialize/use
debugfs attributes"), pers_pageframes|_max are exported in debugfs, but
this commit forgot use array export pers_pageframes|_max. This patch add
pers_pageframes|_max back.
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Wanpeng Li [Tue, 2 Apr 2013 02:46:15 +0000 (10:46 +0800)]
staging: zcache: handle zcache_[eph|pers]_zpages for zero-filled page
Increment/decrement zcache_[eph|pers]_zpages for zero-filled pages,
the main point of the counters for zpages and pageframes is to be
able to calculate density == zpages/pageframes. A zero-filled page
becomes a zpage that "compresses" to zero bytes and, as a result,
requires zero pageframes for storage. So the zpages counter should
be increased but the pageframes counter should not.
[Dan Magenheimer <dan.magenheimer@oracle.com>: patch description] Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Wanpeng Li [Tue, 2 Apr 2013 02:46:14 +0000 (10:46 +0800)]
staging: zcache: zero-filled pages awareness
Compression of zero-filled pages can unneccessarily cause internal
fragmentation, and thus waste memory. This special case can be
optimized.
This patch captures zero-filled pages, and marks their corresponding
zcache backing page entry as zero-filled. Whenever such zero-filled
page is retrieved, we fill the page frame with zero.
Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bob Liu [Tue, 2 Apr 2013 02:47:43 +0000 (10:47 +0800)]
drivers: staging: zcache: fix compile warning
Fix below compile warning:
staging/zcache/zcache-main.c: In function ‘zcache_autocreate_pool’:
staging/zcache/zcache-main.c:1393:13: warning: ‘cli’ may be used uninitialized
in this function [-Wuninitialized]
Signed-off-by: Bob Liu <bob.liu@oracle.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bob Liu [Tue, 2 Apr 2013 02:47:42 +0000 (10:47 +0800)]
drivers: staging: zcache: fix compile error
Because 'ramster_debugfs_init' is not defined if !CONFIG_DEBUG_FS, there is
compile error:
$ make drivers/staging/zcache/
staging/zcache/ramster/ramster.c: In function ‘ramster_init’:
staging/zcache/ramster/ramster.c:981:2: error: implicit declaration of
function ‘ramster_debugfs_init’ [-Werror=implicit-function-declaration]
This patch fix it and reduce some #ifdef CONFIG_DEBUG_FS in .c files the same
way.
Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Bob Liu <bob.liu@oracle.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge tag 'iio-for-3.10c' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next
Jonathan writes:
Third round of IIO cleanups, graduations and new stuff for the 3.10 cycle.
A small set including 3 things.
1) A short cleanup series for the ak8975.
2) Graduation of ak8975 out of staging.
3) Some additional bits for the at91 adc driver to cover low resolution
modes, sleep and a little bit of missing documentation.
On the at91_adc a minimal Sample and Hold Time is necessary for the ADC to
guarantee the best converted final value between two channels selection.
This time has to be programmed through the bitfield SHTIM in the
Mode Register ADC_MR.
at91 adc offers the choice between two resolutions: low and high.
The low and high resolution values depends on adc IP version, as many IP
properties have been exposed through device tree, these settings have also
been added to the dt bindings.
Jonathan Cameron [Sun, 24 Mar 2013 16:58:00 +0000 (16:58 +0000)]
staging:iio:magnetometer:ak8975 use standard i2c_smbus read functions.
Now the mysterious NOSTART flag is gone from the read, we can use the
i2c_smbus_read_byte/word/i2c_block_data functions instead of the
local reimplementation of these standard functions.
Signed-off-by: Jonathan Cameron <jic23@kernel.org> Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Jonathan Cameron [Sun, 24 Mar 2013 16:58:00 +0000 (16:58 +0000)]
staging:iio:magnetometer:ak8975 drop I2C_M_NOSTART flag in read_data
This flag makes no sense whatsoever where it is.
Documentation/i2c/i2c-protocol states:
If you set the I2C_M_NOSTART variable for the first partial message,
we do not generate Addr, but we do generate the startbit S. This will
probably confuse all other clients on your bus, so don't try this.
This is exactly what is going on here. Likelihood given that the
driver never checked for this protocol mangling being available is that
it wasn't present on the test boards and hence this flag was simply
ignored. No indication of why it would be necessary has been found in
the datasheets.
Signed-off-by: Jonathan Cameron <jic23@kernel.org> Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
staging: ti-soc-thermal:Introduce ti_bandgap_get_trend function for OMAP5
The patch adds ti_bandgap_get_trend function. This is specific
to OMAP5 for now it computes the trend from the temp values stored
in the hardware history buffer.
Formula: (T1 - T2) / P.
Where:
T1: Last read valid temperature.
T2: Last but one read valid temperature.
P: Update Interval.
projects / linux-beck.git / log