pinctrl: rp1: Honour direction in legacy brcm,function in/out - #7521
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pinctrl: rp1: Honour direction in legacy brcm,function in/out#7521nbuchwitz wants to merge 2 commits into
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The legacy brcm,function values 0 and 1 select GPIO input and output as on BCM283x, but on RP1 the legacy map only muxes the pin to GPIO and never programs the RIO output enable, so the direction is left as-is. An interrupt line declared with brcm,function = <0> can stay an output. On Pi 5 the sc16is7xx overlay then storms its shared IRQ and saturates a CPU core. Many overlays declare their input and interrupt pins this way, so they share the same latent misconfiguration on RP1. Emit a direction config from the legacy map and let input and output enable program the RIO direction when the pin is a GPIO. Fixes: e3ce7b8 ("pinctrl: rp1: Implement RaspberryPi RP1 pinmux/pinconf support") Link: raspberrypi#7520 Signed-off-by: Nicolai Buchwitz <nb@tipi-net.de>
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Drop the leaked rp1_node reference and test of_iomap() for NULL instead of IS_ERR(), which never matches its return value. Fixes: df868dc ("pinctrl: Reinstate the downstream pinctrl-rp1 driver") Signed-off-by: Nicolai Buchwitz <nb@tipi-net.de>
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The legacy brcm,function values 0 and 1 select GPIO input and output as on BCM283x, but on RP1 the legacy map only muxes the pin to GPIO and never programs the RIO output enable, so the direction is left as-is. An interrupt line declared with brcm,function = <0> can stay an output. On Pi 5 the sc16is7xx overlay then storms its shared IRQ and saturates a CPU core.
Many overlays declare their input and interrupt pins this way, so they share the same latent misconfiguration on RP1.
Emit a direction config from the legacy map and let input and output enable program the RIO direction when the pin is a GPIO.
Fixes: e3ce7b8 ("pinctrl: rp1: Implement RaspberryPi RP1 pinmux/pinconf support")
Link: #7520