| Message ID | 20220119181915.27519-1-andriy.shevchenko@linux.intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v1,1/1] pinctrl: intel: Fix a glitch when updating IRQ flags on a preconfigured line | expand |
On Wed, Jan 19, 2022 at 08:19:15PM +0200, Andy Shevchenko wrote: > 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> Please mark this for stable too.
On Thu, Jan 20, 2022 at 09:44:52AM +0200, Mika Westerberg wrote: > On Wed, Jan 19, 2022 at 08:19:15PM +0200, Andy Shevchenko wrote: > > 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> > > Please mark this for stable too. Pushed to my review and testing queue with the Grace Kao's tag, thanks!
diff --git a/drivers/pinctrl/intel/pinctrl-intel.c b/drivers/pinctrl/intel/pinctrl-intel.c index 7d8a7e7b0aef..4d718a928288 100644 --- a/drivers/pinctrl/intel/pinctrl-intel.c +++ b/drivers/pinctrl/intel/pinctrl-intel.c @@ -451,8 +451,8 @@ static void intel_gpio_set_gpio_mode(void __iomem *padcfg0) 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 */ @@ -497,9 +497,6 @@ static int intel_gpio_request_enable(struct pinctrl_dev *pctldev, 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; @@ -1115,9 +1112,6 @@ static int intel_gpio_irq_type(struct irq_data *d, unsigned int type) 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);
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> --- drivers/pinctrl/intel/pinctrl-intel.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-)