Commit Graph

13 Commits

Author SHA1 Message Date
Kent Gibson
4682427241 gpiolib: cdev: refactor lineevent cleanup into lineevent_free
Consolidate the cleanup of lineevents, currently duplicated in
lineevent_create and lineevent_release, into a helper function
lineevent_free.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-07-12 10:22:01 +02:00
Kent Gibson
883f919818 gpiolib: cdev: refactor linehandle cleanup into linehandle_free
Consolidate the cleanup of linehandles, currently duplicated in
linehandle_create and linehandle_release, into a helper function
linehandle_free.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-07-12 10:22:01 +02:00
Kent Gibson
1bf7ba4001 gpiolib: cdev: remove recalculation of offset
Remove recalculation of offset from desc, where desc itself was calculated
from offset.

There is no benefit from the desc -> hwgpio conversion in this context.
The only implicit benefit of the offset -> desc -> hwgpio is
the range check in the offset -> desc, but where desc is required you
still get that, and where desc isn't required it is simpler to perform
the range check directly.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-07-12 10:22:01 +02:00
Kent Gibson
f30ef3e837 gpiolib: cdev: fix minor race in GET_LINEINFO_WATCH
Merge separate usage of test_bit/set_bit into test_and_set_bit to remove
the possibility of a race between the test and set.

Similarly test_bit and clear_bit.

In the existing code it is possible for two threads to race past the
test_bit and then set or clear the watch bit, and neither return EBUSY.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-07-12 10:22:01 +02:00
Kent Gibson
e2b781c5f0 gpiolib: cdev: rename priv to cdev
Rename priv to cdev to improve readability.

The name "priv" indicates that the object is pointed to by
file->private_data, not what the object is actually is.
As it is always used to point to a struct gpio_chardev_data, renaming
it to cdev is more appropriate.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-07-12 10:22:00 +02:00
Kent Gibson
6accc376a7 gpiolib: cdev: use blocking notifier call chain instead of atomic
Replace usage of atomic_notifier_call_chain with
blocking_notifier_call_chain as the notifier function,
lineinfo_changed_notify, calls gpio_desc_to_lineinfo,
which calls pinctrl_gpio_can_use_line, which can sleep.

The chain isn't being called from an atomic context so the
the blocking notifier is a suitable substitute.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-07-12 10:22:00 +02:00
Kent Gibson
0cdc85a371 gpiolib: cdev: remove pointless decrement of i
Remove pointless decrement of variable, and associated comment.

While i is used subsequently, it is re-initialized so this decrement
serves no purpose.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-07-12 10:22:00 +02:00
Kent Gibson
52b7b596dd gpiolib: cdev: rename numdescs to num_descs
Rename numdescs to num_descs to be more consistent with the naming of
other counters and improve readability.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-07-12 10:22:00 +02:00
Kent Gibson
49bc52798d gpiolib: cdev: rename 'filep' and 'filp' to 'file' to be consistent with other use
Rename 'filep' and 'filp' to 'file' to be consistent with other use
and improve readability.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-07-12 10:22:00 +02:00
Kent Gibson
c274b58a4b gpiolib: cdev: refactor gpiohandle_flags_to_desc_flags
Refactor the mapping from handle flags to desc flags into a helper
function.

The assign_bit is overkill where it is replacing the set_bit cases, as is
rechecking bits known to be clear in some circumstances, but the DRY
simplification more than makes up for any performance degradation,
especially as this is not a hot path.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-07-12 10:22:00 +02:00
Kent Gibson
a18512e3f1 gpiolib: cdev: minor indentation fixes
Make indentation consistent with other use to improve readability.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-07-12 10:22:00 +02:00
Kent Gibson
d189f6270f gpiolib: cdev: sort includes
Sort the includes of gpiolib-cdev.c to make it easier to identify if a
module is included and to avoid duplication.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-07-12 10:22:00 +02:00
Kent Gibson
925ca36913 gpiolib: split character device into gpiolib-cdev
Split the cdev specific functionality out of gpiolib.c and into
gpiolib-cdev.c. This improves the readability and maintainability of both
the cdev and core gpiolib code.

Suggested-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Link: https://lore.kernel.org/r/20200616093615.5167-1-warthog618@gmail.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2020-06-20 22:38:37 +02:00