u-boot/arch
Raviteja Narayanam 486f25c727 arm64: zynqmp: Add 'i2c-mux-idle-disconnect' property
I2C muxes that have the slave devices with same address are
falling into the below problem.

VCK190 system controller (SC) - zynqmp-e-a2197-00-revA.dts
I2C1 (0xff030000) -> Mux1 (@0x74) -> Channel 3 -> 0x50
I2C1 (0xff030000) -> Mux2 (@0x75) -> Channel 0 -> 0x50

1. SC accesses I2C1 - Mux1 (0x74) - Channel 3 and then
2. SC accesses I2C1 - Mux2 (0x75) - Channel 0.

Now it results in 2 slave devices with same address (0x50)
on the I2C bus, making the communication un-reliable.

When ' i2c-mux-idle-disconnect' is in DT, after '1', the Mux
channel output is disconnected, making none of the channels
available to the I2C1. So, there is no question of having the
same addressed slave (0x50) present on the bus when we are doing '2'.

Same pattern is seen in below two boards also.

ZCU208 - zynqmp-zcu208-revA.dts
ZCU216 - zynqmp-zcu216-revA.dts

Signed-off-by: Raviteja Narayanam <raviteja.narayanam@xilinx.com>
2021-05-19 09:44:50 +02:00
..
arc lmb: move CONFIG_LMB in Kconfig 2021-04-22 14:09:45 -04:00
arm arm64: zynqmp: Add 'i2c-mux-idle-disconnect' property 2021-05-19 09:44:50 +02:00
m68k allow opting out of WATCHDOG_RESET() from timer interrupt 2021-04-28 10:05:13 +02:00
microblaze lmb: move CONFIG_LMB in Kconfig 2021-04-22 14:09:45 -04:00
mips mips: octeon: ebb7304: Add support for some I2C devices 2021-04-28 10:05:12 +02:00
nds32 lmb: move CONFIG_LMB in Kconfig 2021-04-22 14:09:45 -04:00
nios2 common: Drop asm/global_data.h from common header 2021-02-02 15:33:42 -05:00
powerpc boards: Disable CMD_SATA on platforms that no longer have a SATA driver enabled 2021-05-11 09:14:56 -04:00
riscv riscv: Group assembly optimized implementation of memory routines into a submenu 2021-05-17 16:47:33 +08:00
sandbox pytest: add sandbox test for "extension" command 2021-05-13 13:09:09 -04:00
sh lmb: move CONFIG_LMB in Kconfig 2021-04-22 14:09:45 -04:00
x86 lmb: move CONFIG_LMB in Kconfig 2021-04-22 14:09:45 -04:00
xtensa lmb: move CONFIG_LMB in Kconfig 2021-04-22 14:09:45 -04:00
.gitignore
Kconfig pytest: add sandbox test for "extension" command 2021-05-13 13:09:09 -04:00
u-boot-elf.lds arch: Add explicit linker script for u-boot-elf 2020-04-03 11:52:55 -04:00