mirror of https://gitee.com/openkylin/linux.git
c825676b08
Port D and port E GPIO loopback modes are commonly enabled via hardware straps for use with front-panel buttons. When the BMC is powered off or fails to boot, the front-panel buttons are directly connected to the host chipset via the loopback to allow direct power-on and reset control. Once the BMC has booted, the loopback mode must be disabled for the BMC to take over control of host power-on and reset. Disabling these loopback modes requires writing to the hardware strap register which violates the current design of assuming the system designer chose the strap settings for a specific reason and they should be treated as read-only. Only the two bits of the strap register related to these loopback modes are allowed to be written and comments have been added to explain why. Signed-off-by: Rick Altherr <raltherr@google.com> Acked-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Andrew Jeffery <andrew@aj.id.au> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> |
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| pinctrl-aspeed-g4.c | ||
| pinctrl-aspeed-g5.c | ||
| pinctrl-aspeed.c | ||
| pinctrl-aspeed.h | ||