tty: pl011: fix initialization order of QDF2400 E44
The work-around for Qualcomm Technologies QDF2400 Erratum 44 hinges on a global variable defined in the pl011 driver. The ACPI SPCR parsing code determines whether the work-around is needed, and if so, it changes the console name from "pl011" to "qdf2400_e44". The expectation is that the pl011 driver will implement the work-around when it sees the console name. The global variable qdf2400_e44_present is set when that happens. The problem is that work-around needs to be enabled when the pl011 driver probes, not when the console name is queried. However, sbsa_probe() is called before pl011_console_match(). The work-around appeared to work previously because the default console on QDF2400 platforms was always ttyAMA1. The first time sbsa_probe() is called (for ttyAMA0), qdf2400_e44_present is still false. Then pl011_console_match() is called, and it sets qdf2400_e44_present to true. All subsequent calls to sbsa_probe() enable the work-around. The solution is to move the global variable into spcr.c and let the pl011 driver query it during probe time. This works because all QDF2400 platforms require SPCR, so parse_spcr() will always be called. pl011_console_match still checks for the "qdf2400_e44" console name, but it doesn't do anything else special. Fixes: 5a0722b8 ("tty: pl011: use "qdf2400_e44" as the earlycon name for QDF2400 E44") Tested-by: NJeffrey Hugo <jhugo@codeaurora.org> Signed-off-by: NTimur Tabi <timur@codeaurora.org> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
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