This is a note to let you know that I've just added the patch titled

pinctrl: intel: Initialize GPIO properly when used through irqchip

to the 4.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: pinctrl-intel-initialize-gpio-properly-when-used-through-irqchip.patch and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From f5a26acf0162477af6ee4c11b4fb9cffe5d3e257 Mon Sep 17 00:00:00 2001

From: Mika Westerberg mika.westerberg@linux.intel.com Date: Wed, 29 Nov 2017 16:25:44 +0300 Subject: pinctrl: intel: Initialize GPIO properly when used through irqchip

From: Mika Westerberg mika.westerberg@linux.intel.com

commit f5a26acf0162477af6ee4c11b4fb9cffe5d3e257 upstream.

When a GPIO is requested using gpiod_get_* APIs the intel pinctrl driver switches the pin to GPIO mode and makes sure interrupts are routed to the GPIO hardware instead of IOAPIC. However, if the GPIO is used directly through irqchip, as is the case with many I2C-HID devices where I2C core automatically configures interrupt for the device, the pin is not initialized as GPIO. Instead we rely that the BIOS configures the pin accordingly which seems not to be the case at least in Asus X540NA SKU3 with Focaltech touchpad.

When the pin is not properly configured it might result weird behaviour like interrupts suddenly stop firing completely and the touchpad stops responding to user input.

Fix this by properly initializing the pin to GPIO mode also when it is used directly through irqchip.

Fixes: 7981c0015af2 ("pinctrl: intel: Add Intel Sunrisepoint pin controller and GPIO support") Reported-by: Daniel Drake drake@endlessm.com Reported-and-tested-by: Chris Chiu chiu@endlessm.com Signed-off-by: Mika Westerberg mika.westerberg@linux.intel.com Signed-off-by: Linus Walleij linus.walleij@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/pinctrl/intel/pinctrl-intel.c | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-)

--- a/drivers/pinctrl/intel/pinctrl-intel.c +++ b/drivers/pinctrl/intel/pinctrl-intel.c @@ -425,6 +425,18 @@ static void __intel_gpio_set_direction(v writel(value, padcfg0); }

+static void intel_gpio_set_gpio_mode(void __iomem *padcfg0) +{ + u32 value; + + /* Put the pad into GPIO mode */ + value = readl(padcfg0) & ~PADCFG0_PMODE_MASK; + /* Disable SCI/SMI/NMI generation */ + value &= ~(PADCFG0_GPIROUTIOXAPIC | PADCFG0_GPIROUTSCI); + value &= ~(PADCFG0_GPIROUTSMI | PADCFG0_GPIROUTNMI); + writel(value, padcfg0); +} + static int intel_gpio_request_enable(struct pinctrl_dev *pctldev, struct pinctrl_gpio_range *range, unsigned pin) @@ -432,7 +444,6 @@ static int intel_gpio_request_enable(str struct intel_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev); void __iomem *padcfg0; unsigned long flags; - u32 value;

raw_spin_lock_irqsave(&pctrl->lock, flags);

@@ -442,13 +453,7 @@ static int intel_gpio_request_enable(str }

padcfg0 = intel_get_padcfg(pctrl, pin, PADCFG0); - /* Put the pad into GPIO mode */ - value = readl(padcfg0) & ~PADCFG0_PMODE_MASK; - /* Disable SCI/SMI/NMI generation */ - value &= ~(PADCFG0_GPIROUTIOXAPIC | PADCFG0_GPIROUTSCI); - value &= ~(PADCFG0_GPIROUTSMI | PADCFG0_GPIROUTNMI); - writel(value, padcfg0); - + intel_gpio_set_gpio_mode(padcfg0); /* Disable TX buffer and enable RX (this will be input) */ __intel_gpio_set_direction(padcfg0, true);

@@ -935,6 +940,8 @@ static int intel_gpio_irq_type(struct ir

raw_spin_lock_irqsave(&pctrl->lock, flags);

+ intel_gpio_set_gpio_mode(reg); + value = readl(reg);

value &= ~(PADCFG0_RXEVCFG_MASK | PADCFG0_RXINV);

Patches currently in stable-queue which might be from mika.westerberg@linux.intel.com are

queue-4.15/pinctrl-intel-initialize-gpio-properly-when-used-through-irqchip.patch queue-4.15/ahci-add-intel-cannon-lake-pch-h-pci-id.patch