Commit Graph

10 Commits

Author SHA1 Message Date
Jamie Iles 280df6b3c3 basic_mmio_gpio: split into a gpio library and platform device
Allow GPIO_BASIC_MMIO_CORE to be used to provide an accessor library
for implementing GPIO drivers whilst abstracting the register access
detail.  Based on a patch from Anton Vorontsov[1] and adapted to allow
bgpio_chip to be embedded in another structure.

Changes since v1:
	- Register the gpio_chip in the platform device probe

1. https://lkml.org/lkml/2011/4/19/401

Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-20 00:40:19 -06:00
Jamie Iles fd99623521 basic_mmio_gpio: convert to non-__raw* accessors
The __raw_* accessors don't include memory barriers and can cause
problems when writes get stuck in write buffers.

Suggested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-20 00:40:17 -06:00
Jamie Iles 31029116eb basic_mmio_gpio: support direction registers
Most controllers require the direction of a GPIO to be set by writing to
a direction register.  Add support for either an input direction
register or an output direction register.

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-20 00:40:17 -06:00
Jamie Iles dd86a0cc5e basic_mmio_gpio: support different input/output registers
Some controllers have separate input and output registers.  For these
controllers, use "set" for the output and "dat" for the input.

Changes since v2: reuse "set" for output and "dat" for input rather than
adding a new "in" register.

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-20 00:40:16 -06:00
Jamie Iles e027d6f9d5 basic_mmio_gpio: detect output method at probe time
Rather than detecting the output method each time in the .set()
callback, do it at probe time and set the appropriate callback.

Changes since v2: moved the reg_dat initialization into
bgpio_setup_io().

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-20 00:40:16 -06:00
Jamie Iles 364b5e8718 basic_mmio_gpio: request register regions
Make sure that we get the register regions with request_mem_region()
before ioremap() to make sure we have exclusive access.

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-20 00:40:16 -06:00
Jamie Iles 924e7a9fc6 basic_mmio_gpio: allow overriding number of gpio
Some platforms may have a number of GPIO that is less than the register
width of the peripheral.

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-20 00:40:15 -06:00
Jamie Iles 4ddb8ae217 basic_mmio_gpio: convert to platform_{get,set}_drvdata()
Use the platform drvdata helpers rather than working on the struct
device itself.

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-20 00:40:14 -06:00
Jamie Iles 8467afec5f basic_mmio_gpio: remove runtime width/endianness evaluation
Remove endianness/width calculations at runtime by installing function
pointers for bit-to-mask conversion and register accessors.

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-20 00:40:14 -06:00
Anton Vorontsov aeec56e331 gpio: add driver for basic memory-mapped GPIO controllers
The basic GPIO controllers may be found in various on-board FPGA and ASIC
solutions that are used to control board's switches, LEDs, chip-selects,
Ethernet/USB PHY power, etc.

These controllers may not provide any means of pin setup
(in/out/open drain).

The driver supports:
- 8/16/32/64 bits registers;
- GPIO controllers with clear/set registers;
- GPIO controllers with a single "data" register;
- Big endian bits/GPIOs ordering (mostly used on PowerPC).

Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: David Brownell <david-b@pacbell.net>
Cc: Samuel Ortiz <sameo@linux.intel.com>,
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27 18:03:06 -07:00