• steven miao's avatar
    Blackfin: gpio: add peripheral group check · 05bbec38
    steven miao authored
    Many Blackfin parts group sets of pins into a single functional unit.
    This means you cannot use different pins within a group for different
    peripherals.  Our resource conflict checking thus far has been limited
    to individual pins, so if someone tried to grab a different pin from
    the same group, it would be allowed while silently changing the other
    pins in the same group.
    
    One common example is the pin set PG12 - PG15 on BF51x parts.  They
    may either be used with SPI0 (1st function), or they may be used with
    PTP/PWM/AMS3 (3rd function).  Ideally, we'd like to use PG12 - PG14
    for SPI0 while using PG15 with AMS3, but the hardware does not permit
    this.  In the past, the software would allow the pins to be requested
    this way, but ultimately things like the Blackfin SPI driver would
    stop working when the hardware rerouted to a different peripheral.
    Signed-off-by: default avatarsteven miao <realmz6@gmail.com>
    Signed-off-by: default avatarMike Frysinger <vapier@gentoo.org>
    05bbec38
bfin_gpio.c 30 KB