Apple SoCs are a distant descendant of Samsung designs and use yet
another variant of their UART style, with different interrupt handling.
In particular, this variant has the following differences with existing
ones:
* It includes a built-in interrupt controller with different registers,
using only a single platform IRQ
* Internal interrupt sources are treated as edge-triggered, even though
the IRQ output is level-triggered. This chiefly affects the TX IRQ
path: the driver can no longer rely on the TX buffer empty IRQ
immediately firing after TX is enabled, but instead must prime the
FIFO with data directly.
Signed-off-by: Hector Martin <marcan@marcan.st>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Tested-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20210304213902.83903-25-marcan@marcan.st
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This macro definitions are necessary to implement DMA transfers
is samsung serial driver.
Based on previous work of Sylwester Nawrocki and Lukasz Czerwinski.
Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial_s3c.h uses upf_t which is defined in serial_core.h but does not
include that itself meaning that users which include serial_s3c.h by
itself don't build.
Signed-off-by: Mark Brown <broonie@linaro.org>
[t.figa: Moved inclusion under #ifndef __ASSEMBLY__ to fix mach-exynos]
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
The registers for the Samsung S3C serial port are currently defined in
the platform specific arch/arm/plat-samsung/include/plat/regs-serial.h
file, which is not visible to multiplatform capable drivers.
Unfortunately, it is not possible to move the file into a more local
place as we should normally try to, because the same registers
may be used in one of four places:
* In the driver itself
* In platform-independent ARM code for early debug output
* In platform_data definitions
* In the Samsung platform power management code
I have also found no way to logically split out a platform_data
file, other than possibly move everything into
include/linux/platform_data, which also felt wrong. The only
part of this file that makes sense to keep specific to the s3c24xx
platform are the virtual and physical addresses defined here,
which are needed in no other location.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Hector Martin