linux-toradex.git/Documentation/gpio/driver.txt, branch v4.4.92

gpio: add a real time compliance notes

2015-10-27T10:13:42+00:00

Put in a compliance checklist.

Signed-off-by: Grygorii Strashko 
Signed-off-by: Linus Walleij

Revert "gpio: add a real time compliance checklist"

2015-10-27T10:13:18+00:00

This reverts commit 677b2ff4afd9996eabefc9472c701211b4b49e87.

gpio: add a real time compliance checklist

2015-10-20T08:17:35+00:00

Add some information about real time compliance to the driver document.
Inspired by Grygorii Strashko's real time compliance patches.

Cc: Grygorii Strashko 
Signed-off-by: Linus Walleij

gpio: rename gpio_lock_as_irq to gpiochip_lock_as_irq

2014-10-28T16:30:59+00:00

This function actually operates on a gpio_chip, so its prefix should
reflect that fact for consistency with other functions defined in
gpio/driver.h.

Signed-off-by: Alexandre Courbot 
Signed-off-by: Linus Walleij

gpio: handle also nested irqchips in the chained handler set-up

2014-09-26T12:39:08+00:00

To unify how we connect cascaded IRQ chips to parent IRQs, if
NULL us passed as handler to the gpiochip_set_chained_irqchip()
function, assume the chips is nested rather than chained, and
we still get the parent set up correctly by way of this function
call.

Alter the drivers for tc3589x and stmpe to use this to set up
their chained handlers as a demonstration of the usage.

Signed-off-by: Linus Walleij

gpio: change gpiochip_request_own_desc() prototype

2014-08-29T06:58:34+00:00

The current prototype of gpiochip_request_own_desc() requires to obtain
a pointer to a descriptor. This is in contradiction to all other GPIO
request schemes, and imposes an extra step of obtaining a descriptor to
drivers. Most drivers actually cannot even perform that step since the
function that does it (gpichip_get_desc()) is gpiolib-private.

Change gpiochip_request_own_desc() to return a descriptor from a
(chip, hwnum) tuple and update users of this function (currently
gpiolib-acpi only).

Signed-off-by: Alexandre Courbot 
Tested-by: Mika Westerberg 
Signed-off-by: Linus Walleij

gpiolib: Export gpiochip_request_own_desc and gpiochip_free_own_desc

2014-07-24T08:25:00+00:00

Both functions were introduced to let gpio drivers request their own
gpio pins. Without exporting the functions, this can however only be
used by gpio drivers built into the kernel.

Secondary impact is that the functions can not currently be used by
platform initialization code associated with the gpio-pca953x driver.
This code permits auto-export of gpio pins through platform data, but
if this functionality is used, the module can no longer be unloaded due
to the problem solved with the introduction of gpiochip_request_own_desc
and gpiochip_free_own_desc.

Export both function so they can be used from modules and from
platform initialization code.

Reviewed-by: Alexandre Courbot 
Reviewed-by: Mika Westerberg 
Signed-off-by: Guenter Roeck 
Signed-off-by: Linus Walleij

gpio: remove gpiod_lock/unlock_as_irq()

2014-07-23T15:43:24+00:00

gpio_lock/unlock_as_irq() are working with (chip, offset) arguments and
are thus not using the old integer namespace. Therefore, there is no
reason to have gpiod variants of these functions working with
descriptors, especially since the (chip, offset) tuple is more suitable
to the users of these functions (GPIO drivers, whereas GPIO descriptors
are targeted at GPIO consumers).

Signed-off-by: Alexandre Courbot 
Signed-off-by: Linus Walleij

gpio: document gpio irqchips a bit more, describe helpers

2014-04-28T19:35:07+00:00

This adds some documentation about the GPIO irqchips, what types
exist etc.

Acked-by: Alexandre Courbot 
Signed-off-by: Linus Walleij

gpio: document how to make combined GPIO+irqchip drivers

2014-02-03T08:11:57+00:00

Write a few words on how GPIO drivers supplying an irqchip should
be written.

Cc: Thomas Gleixner 
Signed-off-by: Linus Walleij