linux-toradex.git/drivers/gpio/max732x.c, branch v2.6.34

gpio: fix probe() error return in gpio driver probes

2009-01-16T00:39:35+00:00

A number of drivers in drivers/gpio return -ENODEV when confronted with
missing setup parameters such as the platform data.  However, returning
-ENODEV causes the driver layer to silently ignore the driver as it
assumes the probe did not find anything and was only speculative.

To make life easier to discern why a driver is not being attached, change
to returning -EINVAL, which is a better description of the fact that the
driver data was not valid.

Also add a set of dev_dbg() statements to the error paths to provide an
better explanation of the error as there may be more that one point in the
driver.

Signed-off-by: Ben Dooks 
Cc: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

gpio: i2c expanders use subsys_init

2008-10-16T18:21:40+00:00

Make the I2C external GPIO expander drivers register themselves at
subsys_initcall() time when they're statically linked.

SOC-integrated GPIOs are available starting very early -- early in
arch_initcall() at latest, but often even before initcalls start to run --
so this improves consistency, so more subsystems can rely on GPIOs in
their own subsys_initcall() code.

(This isn't a theoretical problem.  This is one of several patches needed
to resolve oopsing observed when statically linking kernels on a DaVinci
EVM.  Its pcf857x GPIOs needed to be available well before some other
drivers initialized.)

Signed-off-by: David Brownell 
Cc: Jean Delvare 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

gpio: max732x driver

2008-07-25T17:53:30+00:00

This adds a driver supporting a family of I2C port expanders from Maxim,
which includes the MAX7319 and MAX7320-7327 chips.

[dbrownell@users.sourceforge.net: minor fixes]
Signed-off-by: Jack Ren 
Signed-off-by: Eric Miao 
Acked-by: Jean Delvare 
Signed-off-by: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds