Commit Graph

4 Commits

Author SHA1 Message Date
Christophe JAILLET
9620ca9011 spi: spi-axi: Free resources on error path
We should go to 'err_put_master' here instead of returning directly.
Otherwise a call to 'spi_master_put' is missing.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-01-09 11:20:46 +00:00
Javier Martinez Canillas
01affe239c spi: spi-axi: Fix module autoload
If the driver is built as a module, autoload won't work because the module
alias information is not filled. So user-space can't match the registered
device with the corresponding module.

Export the module alias information using the MODULE_DEVICE_TABLE() macro.

Before this patch:

$ modinfo drivers/spi/spi-axi-spi-engine.ko | grep alias
$

After this patch:

$ modinfo drivers/spi/spi-axi-spi-engine.ko | grep alias
alias:          of:N*T*Cadi,axi-spi-engine-1.00.aC*
alias:          of:N*T*Cadi,axi-spi-engine-1.00.a

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-11-23 16:42:08 +00:00
Axel Lin
71c5e53b42 spi: Drop duplicate code to set master->dev.parent
It's done by spi_alloc_master().

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-04-26 11:56:09 +01:00
Lars-Peter Clausen
b1353d1c1d spi: Add Analog Devices AXI SPI Engine controller support
This patch adds support for the AXI SPI Engine controller which is a FPGA
soft-peripheral which is used in some of Analog Devices' reference designs.

The AXI SPI Engine controller is part of the SPI Engine framework[1] and
allows memory mapped access to the SPI Engine control bus. This allows it
to be used as a general purpose software driven SPI controller. The SPI
Engine in addition offers some optional advanced acceleration and
offloading capabilities, which are not part of this patch though and will
be introduced separately.

At the core of the SPI Engine framework is a small sort of co-processor
that accepts a command stream and turns the commands into low-level SPI
transactions. Communication is done through three memory mapped FIFOs in
the register map of the AXI SPI Engine peripheral. One FIFO for the command
stream and one each for transmit and receive data.

The driver translates a spi_message in a command stream and writes it to
the peripheral which executes it asynchronously. This allows it to perform
very precise timings which are required for some SPI slave devices to
achieve maximum performance (e.g. analog-to-digital and digital-to-analog
converters). The execution flow is synchronized to the host system by a
special synchronize instruction which generates a interrupt.

[1] https://wiki.analog.com/resources/fpga/peripherals/spi_engine

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-05 18:12:57 +00:00