The MULTIPLEXER question in the Kconfig might be confusing and is
of dubious value. Remove it. This makes consumers responsible for
selecting MULTIPLEXER, which they already do.
Signed-off-by: Peter Rosin <peda@axentia.se>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
COMPILE_TEST makes no sense when I2C is disabled, as the driver cannot compile
in that configuration:
drivers/mux/mux-adg792a.c: In function 'adg792a_write_cmd':
drivers/mux/mux-adg792a.c:34:9: error: implicit declaration of function 'i2c_smbus_write_byte_data'; did you mean 'i2c_set_clientdata'? [-Werror=implicit-function-declaration]
drivers/mux/mux-adg792a.o: In function `adg792a_driver_init':
mux-adg792a.c:(.init.text+0x14): undefined reference to `i2c_register_driver'
drivers/mux/mux-adg792a.o: In function `adg792a_probe':
mux-adg792a.c:(.text.adg792a_probe+0x94): undefined reference to `i2c_smbus_write_byte_data'
drivers/mux/mux-adg792a.o: In function `adg792a_set':
mux-adg792a.c:(.text.adg792a_set+0x80): undefined reference to `i2c_smbus_write_byte_data'
Fixes: afda08c4ca ("mux: adg792a: add mux controller driver for ADG792A/G")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This adds a driver for mmio-based syscon multiplexers controlled by
bitfields in a syscon register range.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Analog Devices ADG792A/G is a triple 4:1 mux.
Reviewed-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver builds a single multiplexer controller using a number
of gpio pins. For N pins, there will be 2^N possible multiplexer
states. The GPIO pins can be connected (by the hardware) to several
multiplexers, which in that case will be operated in parallel.
Reviewed-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a new minimalistic subsystem that handles multiplexer controllers.
When multiplexers are used in various places in the kernel, and the
same multiplexer controller can be used for several independent things,
there should be one place to implement support for said multiplexer
controller.
A single multiplexer controller can also be used to control several
parallel multiplexers, that are in turn used by different subsystems
in the kernel, leading to a need to coordinate multiplexer accesses.
The multiplexer subsystem handles this coordination.
Thanks go out to Lars-Peter Clausen, Jonathan Cameron, Rob Herring,
Wolfram Sang, Paul Gortmaker, Dan Carpenter, Colin Ian King, Greg
Kroah-Hartman and last but certainly not least to Philipp Zabel for
helpful comments, reviews, patches and general encouragement!
Reviewed-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
