diff options
Diffstat (limited to 'arch/avr32/mach-at32ap/pio.c')
-rw-r--r-- | arch/avr32/mach-at32ap/pio.c | 63 |
1 files changed, 47 insertions, 16 deletions
diff --git a/arch/avr32/mach-at32ap/pio.c b/arch/avr32/mach-at32ap/pio.c index 405ee6bad4c..ed81a8bcb22 100644 --- a/arch/avr32/mach-at32ap/pio.c +++ b/arch/avr32/mach-at32ap/pio.c @@ -50,35 +50,48 @@ static struct pio_device *gpio_to_pio(unsigned int gpio) } /* Pin multiplexing API */ +static DEFINE_SPINLOCK(pio_lock); -void __init at32_select_periph(unsigned int pin, unsigned int periph, - unsigned long flags) +void __init at32_select_periph(unsigned int port, u32 pin_mask, + unsigned int periph, unsigned long flags) { struct pio_device *pio; - unsigned int pin_index = pin & 0x1f; - u32 mask = 1 << pin_index; - pio = gpio_to_pio(pin); + /* assign and verify pio */ + pio = gpio_to_pio(port); if (unlikely(!pio)) { - printk("pio: invalid pin %u\n", pin); + printk(KERN_WARNING "pio: invalid port %u\n", port); goto fail; } - if (unlikely(test_and_set_bit(pin_index, &pio->pinmux_mask) - || gpiochip_is_requested(&pio->chip, pin_index))) { - printk("%s: pin %u is busy\n", pio->name, pin_index); + /* Test if any of the requested pins is already muxed */ + spin_lock(&pio_lock); + if (unlikely(pio->pinmux_mask & pin_mask)) { + printk(KERN_WARNING "%s: pin(s) busy (requested 0x%x, busy 0x%x)\n", + pio->name, pin_mask, pio->pinmux_mask & pin_mask); + spin_unlock(&pio_lock); goto fail; } - pio_writel(pio, PUER, mask); + pio->pinmux_mask |= pin_mask; + + /* enable pull ups */ + pio_writel(pio, PUER, pin_mask); + + /* select either peripheral A or B */ if (periph) - pio_writel(pio, BSR, mask); + pio_writel(pio, BSR, pin_mask); else - pio_writel(pio, ASR, mask); + pio_writel(pio, ASR, pin_mask); + + /* enable peripheral control */ + pio_writel(pio, PDR, pin_mask); - pio_writel(pio, PDR, mask); + /* Disable pull ups if not requested. */ if (!(flags & AT32_GPIOF_PULLUP)) - pio_writel(pio, PUDR, mask); + pio_writel(pio, PUDR, pin_mask); + + spin_unlock(&pio_lock); return; @@ -134,6 +147,25 @@ fail: dump_stack(); } +/* + * Undo a previous pin reservation. Will not affect the hardware + * configuration. + */ +void at32_deselect_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); + dump_stack(); + return; + } + + clear_bit(pin_index, &pio->pinmux_mask); +} + /* Reserve a pin, preventing anyone else from changing its configuration. */ void __init at32_reserve_pin(unsigned int pin) { @@ -382,7 +414,6 @@ static int __init pio_probe(struct platform_device *pdev) } static struct platform_driver pio_driver = { - .probe = pio_probe, .driver = { .name = "pio", }, @@ -390,7 +421,7 @@ static struct platform_driver pio_driver = { static int __init pio_init(void) { - return platform_driver_register(&pio_driver); + return platform_driver_probe(&pio_driver, pio_probe); } postcore_initcall(pio_init); |