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authorChia-Wei Wang <chiawei_wang@aspeedtech.com>2021-10-22 10:36:16 +1030
committerArnd Bergmann <arnd@arndb.de>2021-10-22 17:32:09 +0200
commitc6807970c3bc0aa80f4804fc7d38b32f99fc3cf6 (patch)
treea9a5907988ac1906c85bb78f937c94476ecc1c3a /Documentation/ABI
parentMerge tag 'soc-fsl-next-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/leo/linux into arm/drivers (diff)
downloadlinux-dev-c6807970c3bc0aa80f4804fc7d38b32f99fc3cf6.tar.xz
linux-dev-c6807970c3bc0aa80f4804fc7d38b32f99fc3cf6.zip
soc: aspeed: Add UART routing support
Add driver support for the UART routing control. Users can perform runtime configuration of the RX muxes among the UART controllers and the UART IO pins. The sysfs interface is also exported for the convenience of routing paths check and update. Signed-off-by: Oskar Senft <osk@google.com> Signed-off-by: Chia-Wei Wang <chiawei_wang@aspeedtech.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Tested-by: Lei YU <yulei.sh@bytedance.com> Link: https://lore.kernel.org/r/20210927023053.6728-5-chiawei_wang@aspeedtech.com Link: https://lore.kernel.org/r/20211022000616.481772-1-joel@jms.id.au' Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'Documentation/ABI')
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+What: /sys/bus/platform/drivers/aspeed-uart-routing/*/uart*
+Date: September 2021
+Contact: Oskar Senft <osk@google.com>
+ Chia-Wei Wang <chiawei_wang@aspeedtech.com>
+Description: Selects the RX source of the UARTx device.
+
+ When read, each file shows the list of available options with currently
+ selected option marked by brackets "[]". The list of available options
+ depends on the selected file.
+
+ e.g.
+ cat /sys/bus/platform/drivers/aspeed-uart-routing/*.uart_routing/uart1
+ [io1] io2 io3 io4 uart2 uart3 uart4 io6
+
+ In this case, UART1 gets its input from IO1 (physical serial port 1).
+
+Users: OpenBMC. Proposed changes should be mailed to
+ openbmc@lists.ozlabs.org
+
+What: /sys/bus/platform/drivers/aspeed-uart-routing/*/io*
+Date: September 2021
+Contact: Oskar Senft <osk@google.com>
+ Chia-Wei Wang <chiawei_wang@aspeedtech.com>
+Description: Selects the RX source of IOx serial port. The current selection
+ will be marked by brackets "[]".
+Users: OpenBMC. Proposed changes should be mailed to
+ openbmc@lists.ozlabs.org