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>
This commit is contained in:
Mika Westerberg 2015-10-21 13:08:44 +03:00 committed by Linus Walleij
parent 193b40c825
commit 4341e8a545

View file

@ -160,8 +160,7 @@ static bool intel_pad_owned_by_host(struct intel_pinctrl *pctrl, unsigned pin)
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_locked(struct intel_pinctrl *pctrl, unsigned pin)
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 @@ static void intel_pin_dbg_show(struct pinctrl_dev *pctldev, struct seq_file *s,
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 @@ static int intel_gpio_irq_type(struct irq_data *d, unsigned type)
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);