A bunch of GPIO fixes for the v4.7 series: - Drop the lock before reading out the GPIO direction setting in drivers supporting the .get_direction() callback: some of them may be slowpath. - Flush GPIO direction setting before locking a GPIO as an IRQ: some electronics or other poking around in the registers behind our back may have happened, so flush the direction status before trying to lock the line for use by IRQs. - Bail out silently when asked to perform operations on NULL GPIO descriptors. That is what all the get_*_optional() is about: we get optional GPIO handles, if they are not there, we get NULL. - Handle compatible ioctl() correctly: we need to convert the ioctl() pointer using compat_ptr() here like everyone else. - Disable the broken .to_irq() on the LPC32xx platform. The whole irqchip infrastructure was replaced in the last merge window, and a new implementation will be needed.