pinctrl: intel: Allow requesting pins which are in ACPI mode as GPIOs
Reserved for ACPI actually means that in such case the GPIO hardware will
not update the interrupt status register (GPI_IS) even if the pin is
configured to trigger an interrupt. It will update GPI_GPE_STS instead and
does not trigger an interrupt.
Allow using such pins as GPIOs, only prevent their usage as interrupts.
We also rename function intel_pad_reserved_for_acpi() to be
intel_pad_acpi_mode() which reflects the actual meaning better.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/intel/pinctrl-intel.c b/drivers/pinctrl/intel/pinctrl-intel.c
index 19b73de..c427454 100644
--- a/drivers/pinctrl/intel/pinctrl-intel.c
+++ b/drivers/pinctrl/intel/pinctrl-intel.c
@@ -160,8 +160,7 @@
return !(readl(padown) & PADOWN_MASK(padno));
}
-static bool intel_pad_reserved_for_acpi(struct intel_pinctrl *pctrl,
- unsigned pin)
+static bool intel_pad_acpi_mode(struct intel_pinctrl *pctrl, unsigned pin)
{
const struct intel_community *community;
unsigned padno, gpp, offset;
@@ -217,7 +216,6 @@
static bool intel_pad_usable(struct intel_pinctrl *pctrl, unsigned pin)
{
return intel_pad_owned_by_host(pctrl, pin) &&
- !intel_pad_reserved_for_acpi(pctrl, pin) &&
!intel_pad_locked(pctrl, pin);
}
@@ -270,7 +268,7 @@
seq_printf(s, "0x%08x 0x%08x", cfg0, cfg1);
locked = intel_pad_locked(pctrl, pin);
- acpi = intel_pad_reserved_for_acpi(pctrl, pin);
+ acpi = intel_pad_acpi_mode(pctrl, pin);
if (locked || acpi) {
seq_puts(s, " [");
@@ -737,6 +735,16 @@
if (!reg)
return -EINVAL;
+ /*
+ * If the pin is in ACPI mode it is still usable as a GPIO but it
+ * cannot be used as IRQ because GPI_IS status bit will not be
+ * updated by the host controller hardware.
+ */
+ if (intel_pad_acpi_mode(pctrl, pin)) {
+ dev_warn(pctrl->dev, "pin %u cannot be used as IRQ\n", pin);
+ return -EPERM;
+ }
+
spin_lock_irqsave(&pctrl->lock, flags);
value = readl(reg);