diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/avr32/mach-at32ap/pio.c | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/arch/avr32/mach-at32ap/pio.c b/arch/avr32/mach-at32ap/pio.c index c3f596ce526..9ba5654cde1 100644 --- a/arch/avr32/mach-at32ap/pio.c +++ b/arch/avr32/mach-at32ap/pio.c @@ -135,7 +135,28 @@ fail: dump_stack(); } -/*--------------------------------------------------------------------------*/ +/* Reserve a pin, preventing anyone else from changing its configuration. */ +void __init at32_reserve_pin(unsigned int pin) +{ + struct pio_device *pio; + unsigned int pin_index = pin & 0x1f; + + pio = gpio_to_pio(pin); + if (unlikely(!pio)) { + printk("pio: invalid pin %u\n", pin); + goto fail; + } + + if (unlikely(test_and_set_bit(pin_index, &pio->pinmux_mask))) { + printk("%s: pin %u is busy\n", pio->name, pin_index); + goto fail; + } + + return; + +fail: + dump_stack(); +} /*--------------------------------------------------------------------------*/ |