[PATCH v1 1/1] pinctrl: intel: Restore the pins that used to be in Direct IRQ mode

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

If the firmware mangled the register contents too much,
check the saved value for the Direct IRQ mode. If it
matches, we will restore the pin state.

Reported-by: Jim Minter <jimminter@microsoft.com>
Fixes: 6989ea4881c8 ("pinctrl: intel: Save and restore pins in "direct IRQ" mode")
Tested-by: Jim Minter <jimminter@microsoft.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---

Jim, this is a bit simplified version than what you tested. But it shouldn't
be a functional changes. Anyway, it would be nice if you have a chance to give
this a try.

Linus, I don't expect more to come for this cycle, feel free to apply directly.

 drivers/pinctrl/intel/pinctrl-intel.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/drivers/pinctrl/intel/pinctrl-intel.c b/drivers/pinctrl/intel/pinctrl-intel.c
index cc3aaba24188..e49f271de936 100644
--- a/drivers/pinctrl/intel/pinctrl-intel.c
+++ b/drivers/pinctrl/intel/pinctrl-intel.c
@@ -1709,6 +1709,12 @@ const struct intel_pinctrl_soc_data *intel_pinctrl_get_soc_data(struct platform_
 EXPORT_SYMBOL_GPL(intel_pinctrl_get_soc_data);
 
 #ifdef CONFIG_PM_SLEEP
+static bool __intel_gpio_is_direct_irq(u32 value)
+{
+	return (value & PADCFG0_GPIROUTIOXAPIC) && (value & PADCFG0_GPIOTXDIS) &&
+	       (__intel_gpio_get_gpio_mode(value) == PADCFG0_PMODE_GPIO);
+}
+
 static bool intel_pinctrl_should_save(struct intel_pinctrl *pctrl, unsigned int pin)
 {
 	const struct pin_desc *pd = pin_desc_get(pctrl->pctldev, pin);
@@ -1742,8 +1748,7 @@ static bool intel_pinctrl_should_save(struct intel_pinctrl *pctrl, unsigned int
 	 * See https://bugzilla.kernel.org/show_bug.cgi?id=214749.
 	 */
 	value = readl(intel_get_padcfg(pctrl, pin, PADCFG0));
-	if ((value & PADCFG0_GPIROUTIOXAPIC) && (value & PADCFG0_GPIOTXDIS) &&
-	    (__intel_gpio_get_gpio_mode(value) == PADCFG0_PMODE_GPIO))
+	if (__intel_gpio_is_direct_irq(value))
 		return true;
 
 	return false;
@@ -1873,7 +1878,12 @@ int intel_pinctrl_resume_noirq(struct device *dev)
 	for (i = 0; i < pctrl->soc->npins; i++) {
 		const struct pinctrl_pin_desc *desc = &pctrl->soc->pins[i];
 
-		if (!intel_pinctrl_should_save(pctrl, desc->number))
+		if (!(intel_pinctrl_should_save(pctrl, desc->number) ||
+		      /*
+		       * If the firmware mangled the register contents too much,
+		       * check the saved value for the Direct IRQ mode.
+		       */
+		      __intel_gpio_is_direct_irq(pads[i].padcfg0)))
 			continue;
 
 		intel_restore_padcfg(pctrl, desc->number, PADCFG0, pads[i].padcfg0);
-- 
2.39.1