| From e12963c453263d5321a2c610e98cbc731233b685 Mon Sep 17 00:00:00 2001 |
| From: Andy Shevchenko <andriy.shevchenko@linux.intel.com> |
| Date: Wed, 19 Jan 2022 20:19:15 +0200 |
| Subject: pinctrl: intel: Fix a glitch when updating IRQ flags on a preconfigured line |
| |
| From: Andy Shevchenko <andriy.shevchenko@linux.intel.com> |
| |
| commit e12963c453263d5321a2c610e98cbc731233b685 upstream. |
| |
| The commit af7e3eeb84e2 ("pinctrl: intel: Disable input and output buffer |
| when switching to GPIO") hadn't taken into account an update of the IRQ |
| flags scenario. |
| |
| When updating the IRQ flags on the preconfigured line the ->irq_set_type() |
| is called again. In such case the sequential Rx buffer configuration |
| changes may trigger a falling or rising edge interrupt that may lead, |
| on some platforms, to an undesired event. |
| |
| This may happen because each of intel_gpio_set_gpio_mode() and |
| __intel_gpio_set_direction() updates the pad configuration with a different |
| value of the GPIORXDIS bit. Notable, that the intel_gpio_set_gpio_mode() is |
| called only for the pads that are configured as an input. Due to this fact, |
| integrate the logic of __intel_gpio_set_direction() call into the |
| intel_gpio_set_gpio_mode() so that the Rx buffer won't be disabled and |
| immediately re-enabled. |
| |
| Fixes: af7e3eeb84e2 ("pinctrl: intel: Disable input and output buffer when switching to GPIO") |
| Reported-by: Kane Chen <kane.chen@intel.com> |
| Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> |
| Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> |
| Tested-by: Grace Kao <grace.kao@intel.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/pinctrl/intel/pinctrl-intel.c | 10 ++-------- |
| 1 file changed, 2 insertions(+), 8 deletions(-) |
| |
| --- a/drivers/pinctrl/intel/pinctrl-intel.c |
| +++ b/drivers/pinctrl/intel/pinctrl-intel.c |
| @@ -441,8 +441,8 @@ static void intel_gpio_set_gpio_mode(voi |
| value &= ~PADCFG0_PMODE_MASK; |
| value |= PADCFG0_PMODE_GPIO; |
| |
| - /* Disable input and output buffers */ |
| - value |= PADCFG0_GPIORXDIS; |
| + /* Disable TX buffer and enable RX (this will be input) */ |
| + value &= ~PADCFG0_GPIORXDIS; |
| value |= PADCFG0_GPIOTXDIS; |
| |
| /* Disable SCI/SMI/NMI generation */ |
| @@ -487,9 +487,6 @@ static int intel_gpio_request_enable(str |
| |
| intel_gpio_set_gpio_mode(padcfg0); |
| |
| - /* Disable TX buffer and enable RX (this will be input) */ |
| - __intel_gpio_set_direction(padcfg0, true); |
| - |
| raw_spin_unlock_irqrestore(&pctrl->lock, flags); |
| |
| return 0; |
| @@ -1105,9 +1102,6 @@ static int intel_gpio_irq_type(struct ir |
| |
| intel_gpio_set_gpio_mode(reg); |
| |
| - /* Disable TX buffer and enable RX (this will be input) */ |
| - __intel_gpio_set_direction(reg, true); |
| - |
| value = readl(reg); |
| |
| value &= ~(PADCFG0_RXEVCFG_MASK | PADCFG0_RXINV); |