summaryrefslogtreecommitdiff
path: root/drivers/bus/Kconfig
diff options
context:
space:
mode:
authorMarek BehĂșn <marek.behun@nic.cz>2019-08-12 19:11:14 +0300
committerArnd Bergmann <arnd@arndb.de>2019-08-14 16:30:35 +0300
commit5bc7f990cd98f3f7977d62bfe75c50b4b33d13f6 (patch)
treedd418e4969d39534a970c240d08bf79964bd461f /drivers/bus/Kconfig
parent5ef9eb7ca372a97d347cf2d38e0ad2209585078b (diff)
downloadlinux-5bc7f990cd98f3f7977d62bfe75c50b4b33d13f6.tar.xz
bus: Add support for Moxtet bus
On the Turris Mox router different modules can be connected to the main CPU board: currently a module with a SFP cage, a module with MiniPCIe connector, a PCIe pass-through MiniPCIe connector module, a 4-port switch module, an 8-port switch module, and a 4-port USB3 module. For example: [CPU]-[PCIe-pass-through]-[PCIe]-[8-port switch]-[8-port switch]-[SFP] Each of this modules has an input and output shift register, and these are connected via SPI to the CPU board. Via SPI we are able to discover which modules are connected, in which order, and we can also read some information about the modules (eg. their interrupt status), and configure them. From each module 8 bits can be read (of which low 4 bits identify the module) and 8 bits can be written. For example from the module with a SFP cage we can read the LOS, TX-FAULT and MOD-DEF0 signals, while we can write TX-DISABLE and RATE-SELECT signals. This driver creates a new bus type, called "moxtet". For each Mox module it finds via SPI, it creates a new device on the moxtet bus so that drivers can be written for them. It also implements a virtual interrupt controller for the modules which send their interrupt status over the SPI shift register. These modules do this in addition to sending their interrupt status via the shared interrupt line. When the shared interrupt is triggered, we read from the shift register and handle IRQs for all devices which are in interrupt. The topology of how Mox modules are connected can then be read by listing /sys/bus/moxtet/devices. Link: https://lore.kernel.org/r/20190812161118.21476-2-marek.behun@nic.cz Signed-off-by: Marek BehĂșn <marek.behun@nic.cz> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'drivers/bus/Kconfig')
-rw-r--r--drivers/bus/Kconfig10
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig
index 1851112ccc29..6b331061d34b 100644
--- a/drivers/bus/Kconfig
+++ b/drivers/bus/Kconfig
@@ -29,6 +29,16 @@ config BRCMSTB_GISB_ARB
arbiter. This driver provides timeout and target abort error handling
and internal bus master decoding.
+config MOXTET
+ tristate "CZ.NIC Turris Mox module configuration bus"
+ depends on SPI_MASTER && OF
+ help
+ Say yes here to add support for the module configuration bus found
+ on CZ.NIC's Turris Mox. This is needed for the ability to discover
+ the order in which the modules are connected and to get/set some of
+ their settings. For example the GPIOs on Mox SFP module are
+ configured through this bus.
+
config HISILICON_LPC
bool "Support for ISA I/O space on HiSilicon Hip06/7"
depends on ARM64 && (ARCH_HISI || COMPILE_TEST)