The parport_gpio_frob_control() op callback has two problems
1) it returns the original value of the control register. Need to verify that's what it's supposed to do or if it matters (does anyone read the result?) Some drivers do what we're doing, others return new control register value.
2) we read and write all four lines unconditionally, but presumably the main use case is to frob one line at a time; for the GPIO implementation, we probably should only frob bits present in the mask argument
The
parport_gpio_frob_control()op callback has two problems1) it returns the original value of the control register. Need to verify that's what it's supposed to do or if it matters (does anyone read the result?) Some drivers do what we're doing, others return new control register value. 2) we read and write all four lines unconditionally, but presumably the main use case is to frob one line at a time; for the GPIO implementation, we probably should only frob bits present in the
maskargument