ACPI / LPSS: power on when probe() and otherwise when remove()
When LPSS drivers are compiled as a module, which is usually the case, the second probe of that driver may fail because the driver is written in an assumption that device is powered on. That is not the case for all drivers. Moreover we would like not drain power in vain. Implement ->activate() and ->dismiss() callbacks in the ACPI LPSS custom power domain. -------- 8< -------- 8< -------- 8< -------- 8< -------- 8< -------- Case 1: The I2C probe() repeat. /sys/bus/platform/devices/808622C1:00 \_SB_.PCI0.I2C1 [D3hot] /sys/bus/platform/devices/808622C1:01 \_SB_.PCI0.I2C2 [D3hot] /sys/bus/platform/devices/808622C1:02 \_SB_.PCI0.I2C3 [D3hot] /sys/bus/platform/devices/808622C1:03 \_SB_.PCI0.I2C4 [D3hot] /sys/bus/platform/devices/808622C1:05 \_SB_.PCI0.I2C6 [D3hot] /sys/bus/platform/devices/808622C1:06 \_SB_.PCI0.I2C7 [D3hot] % modprobe i2c-designware-platform i2c_designware 808622C1:00: Unknown Synopsys component type: 0xffffffff i2c_designware 808622C1:01: Unknown Synopsys component type: 0xffffffff i2c_designware 808622C1:02: Unknown Synopsys component type: 0xffffffff i2c_designware 808622C1:03: Unknown Synopsys component type: 0xffffffff i2c_designware 808622C1:05: Unknown Synopsys component type: 0xffffffff i2c_designware 808622C1:06: Unknown Synopsys component type: 0xffffffff Case 2: The power drain in case of SDHCI. /sys/bus/platform/devices/80860F14:00 \_SB_.PCI0.SDHA [D3hot] /sys/bus/platform/devices/80860F14:01 \_SB_.PCI0.SDHC [D3hot] % modprobe -r sdhci-acpi mmc0: card 0001 removed /sys/bus/platform/devices/80860F14:00 \_SB_.PCI0.SDHA [D0] /sys/bus/platform/devices/80860F14:01 \_SB_.PCI0.SDHC [D0] -------- 8< -------- 8< -------- 8< -------- 8< -------- 8< -------- Patch fixes above problems. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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