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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
