cycle_kernel_lock() was added during the big BKL pushdown. It should
ensure the serializiation against driver init code. In this case there
is nothing to serialize. Remove it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <20091010153350.167321547@linutronix.de>
Acked-by: Jim Cromie <jim.cromie@gmail.com>

All of the open() functions which don't need the BKL on their face may
still depend on its acquisition to serialize opens against driver
initialization.  So make those functions acquire then release the BKL to be
on the safe side.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This documents the fact that somebody looked at the relevant open()
functions and concluded that, due to their trivial nature, no locking was
needed.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Use EXPORT_SYMBOL_GPL for new symbols, and declare the struct in the header
file for access by other modules.

Signed-off-by: Chris Boot <bootc@bootc.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

This patch makes a needlessly global variable static.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Jim Cromie  <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

- rename EXPORTed gpio vtables from {scx200,pc8736x}_access to _gpio_ops new
  name is much closer to the vtable-name struct nsc_gpio_ops, should be
  clearer.  Also rename the _fops vtable var to _fileops to better
  disambiguate it from the gpio vtable.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drops gpio_set_high, gpio_set_low from the nsc_gpio_ops vtable.  While we
can't drop them from scx200_gpio (or can we?), we dont need them for new users
of the exported vtable; gpio_set(1), gpio_set(0) work fine.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Remove the scx200_gpio's cdev-array & ksalloc, replacing it with a single
static struct cdev, which is sufficient for all the pins.

cdev_put is commented out since kernel wont link properly with it, and its
apparently not needed.

With these patches, this driver continues to work with Chris Boot's
leds_48xx driver.

Signed-off-by  Jim Cromie <jim.cromie@gmail.com>

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

this patch is mostly cleanup of scx200_gpio :
- drop #include <linux/config.h>
- s/DEVNAME/DRVNAME/    apparently a convention
- replace variable num_pins with  #define MAX_PINS
- s/dev/devid/   to clarify that its a dev_t, not a struct device dev.
- move devid = MKDEV(major,0)  into branch where its needed.

2 minor 'changes' :

- reduced MAX_PINS from 64 to 32.  Ive never tested other pins, and
  theyre all multiplexed with other functions, some of which may be in use
  on my soekris 4801, so I dont know what testing should yield.

- +EXPORT_SYMBOL(scx200_access);

  This exposes the driver's vtable, which another driver can use along
  with #include <linux/nsc_gpio.h>, to manipulate a gpio-pin.

Signed-off-by  Jim Cromie <jim.cromie@gmail.com>

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Mark the static struct file_operations in drivers/char as const.  Making
them const prevents accidental bugs, and moves them to the .rodata section
so that they no longer do any false sharing; in addition with the proper
debug option they are then protected against corruption..

[akpm@osdl.org: build fix]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>