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Diffstat (limited to 'arch/avr32/mach-at32ap/pio.c')
-rw-r--r--arch/avr32/mach-at32ap/pio.c63
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);