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  1. 11 2月, 2016 1 次提交
    • N
      gpio: add tps65218 gpio · c366c76a
      由 Nicolas Saenz Julienne 提交于 
      Driver for the GPIO block found in ti's tps65218 pmics.

The device has two GPIOs and one GPO pin which can be configured as follows:
GPIO1:
	-general-purpose, open-drain output controlled by GPO1 user bit and/or
	 sequencer
	-DDR3 reset input signal from SOC. Signal is either latched or
	 passed-trough to GPO2 pin. See below for details.
GPO2:
	-general-purpose output controlled by GPO2 user bit
	-DDR3 reset output signal. Signal is controlled by GPIO1 and PGOOD.
	 See below for details.
	-Output buffer can be configured as open-drain or push-pull.
GPIO3:
	-general-purpose, open-drain output controlled by GPO3 user bit and/or
	 sequencer
	-reset input-signal for DCDC1 and DCDC2.

The input configurations are not meant to be used by the user so the driver
only offers GPOs.

v2: Added request routine that evaluates the fw config flags and removed module
    owner
v3: Added .direction_input() routine, and took care of all Linus Walleij
suggestions (clamp to bool, use proper include)
Signed-off-by: NNicolas Saenz Julienne <nicolassaenzj@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
      c366c76a
  3. 10 2月, 2016 7 次提交
  5. 09 2月, 2016 4 次提交
    • L
      gpio: add a userspace chardev ABI for GPIOs · 3c702e99
      由 Linus Walleij 提交于 
      A new chardev that is to be used for userspace GPIO access is
added in this patch. It is intended to gradually replace the
horribly broken sysfs ABI.

Using a chardev has many upsides:

- All operations are per-gpiochip, which is the actual
  device underlying the GPIOs, making us tie in to the
  kernel device model properly.

- Hotpluggable GPIO controllers can come and go, as this
  kind of problem has been know to userspace for character
  devices since ages, and if a gpiochip handle is held in
  userspace we know we will break something, whereas the
  sysfs is stateless.

- The one-value-per-file rule of sysfs is really hard to
  maintain when you want to twist more than one knob at a time,
  for example have in-kernel APIs to switch several GPIO
  lines at the same time, and this will be possible to do
  with a single ioctl() from userspace, saving a lot of
  context switching.

We also need to add a new bus type for GPIO. This is
necessary for example for userspace coldplug, where sysfs is
traversed to find the boot-time device nodes and create the
character devices in /dev.

This new chardev ABI is *non* *optional* and can be counted
on to be present in the future, emphasizing the preference
of this ABI.

The ABI only implements one single ioctl() to get the name
and number of GPIO lines of a chip. Even this is debatable:
see it as a minimal example for review. This ABI shall be
ruthlessly reviewed and etched in stone.

The old /sys/class/gpio is still optional to compile in,
but will be deprecated.

Unique device IDs are created using IDR, which is overkill
and insanely scalable, but also well tested.

Cc: Johan Hovold <johan@kernel.org>
Cc: Michael Welling <mwelling@ieee.org>
Cc: Markus Pargmann <mpa@pengutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
      3c702e99
    • L
      gpio: refer to gpio device in prints and debugfs · 34ffd85d
      由 Linus Walleij 提交于 
      We use the new struct device inside gpio_chip to related debug
prints and warnings, and we also add it to the debugfs dump.

Cc: Johan Hovold <johan@kernel.org>
Cc: Michael Welling <mwelling@ieee.org>
Cc: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
      34ffd85d
    • L
      gpio: make the gpiochip a real device · ff2b1359
      由 Linus Walleij 提交于 
      GPIO chips have been around for years, but were never real devices,
instead they were piggy-backing on a parent device (such as a
platform_device or amba_device) but this was always optional.
GPIO chips could also exist without any device at all, with its
struct device *parent (ex *dev) pointer being set to null.

When sysfs was in use, a mock device would be created, with the
optional parent assigned, or just floating orphaned with NULL
as parent.

If sysfs is active, it will use this device as parent.

We now create a gpio_device struct containing a real
struct device and move the subsystem over to using that. The
list of struct gpio_chip:s is augmented to hold struct
gpio_device:s and we find gpio_chips:s by first looking up
the struct gpio_device.

The struct gpio_device is designed to stay around even if the
gpio_chip is removed, so as to satisfy users in userspace
that need a backing data structure to hold the state of the
session initiated with e.g. a character device even if there is
no physical chip anymore.

From this point on, gpiochips are devices.

Cc: Johan Hovold <johan@kernel.org>
Cc: Michael Welling <mwelling@ieee.org>
Cc: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
      ff2b1359
    • L
      drivers/gpio: Switch gpio-mpc8xxx to use gpio-generic · 42178e2a
      由 Liu Gang 提交于 
      The new Layerscape platforms has the same ip block/controller
as GPIO on PowerPC platforms(MPC8XXX), but the GPIO registers
may be big or little endian. So the code needs to get the
endian property from DTB, then make additional functions to
fit all the PowerPC/Layerscape GPIO register read/write
operations.

gpio-generic.c provides an universal infrastructure for both
big and little endian register operations. So switch the
gpio-mpc8xxx to use gpio-generic can simplify the driver and
reduce a lot of code.

The IRQ and some workaround parts in gpio-mpc8xxx.c will be
updated with the new API interfaces but following the
original functionalities.
Signed-off-by: NLiu Gang <Gang.Liu@nxp.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
      42178e2a
  7. 05 2月, 2016 1 次提交
  9. 28 1月, 2016 6 次提交
  11. 13 1月, 2016 3 次提交
  13. 11 1月, 2016 1 次提交
  15. 07 1月, 2016 4 次提交
  17. 05 1月, 2016 13 次提交