[PATCH v2 00/13] acpi: i2c: Use SharedAndWake and ExclusiveAndWake to enable wake irq

Today, i2c drivers are making the assumption that their IRQs can also
be used as wake IRQs. This isn't always the case and it can lead to
spurious wakes. This has recently started to affect AMD Chromebooks.
With the introduction of
d62bd5ce12d7 ("pinctrl: amd: Implement irq_set_wake"), the AMD GPIO
controller gained the capability to set the wake bit on each GPIO. The
ACPI specification defines two ways to inform the system if a device is
wake capable:
1) The _PRW object defines the GPE that can be used to wake the system.
2) Setting ExclusiveAndWake or SharedAndWake in the _CRS GpioInt.

Currently only the first method is supported. The i2c drivers don't have
any indication that the IRQ is wake capable, so they guess. This causes
spurious interrupts, for example:
* We have an ACPI HID device that has `_PR0` and `_PR3`. It doesn't have
  `_PRW` or `ExclusiveAndWake` so that means the device can't wake the
  system.
* The IRQ line is active level low for this device and is pulled up by
  the power resource defined in `_PR0`/`_PR3`.
* The i2c driver will (incorrectly) arm the GPIO for wake by calling
  `enable_irq_wake` as part of its suspend hook.
* ACPI will power down the device since it doesn't have a wake GPE
  associated with it.
* When the device is powered down, the IRQ line will drop, and it will
  trigger a wake event.

See the following debug log:
[   42.335804] PM: Suspending system (s2idle)
[   42.340186] amd_gpio AMD0030:00: RX: Setting wake for pin 89 to enable
[   42.467736]     power-0416 __acpi_power_off      : Power resource [PR00] turned off
[   42.467739] device_pm-0280 device_set_power      : Device [H05D] transitioned to D3cold
[   42.475210] PM: pm_system_irq_wakeup: 11 triggered pinctrl_amd
[   42.535293] PM: Wakeup unrelated to ACPI SCI
[   42.535294] PM: resume from suspend-to-idle

In order to fix this, we need to take into account the wake capable bit
defined on the Interrupt/GpioInt. This is accomplished by:
* Migrating some of the i2c drivers over to using the PM subsystem to
  manage the wake IRQ.
* Expose the wake_capable bit from the ACPI Interrupt/GpioInt resource
  to the  i2c core.
* Use the wake_capable bit in the i2c core to call
  `dev_pm_set_wake_irq`. This reuses the existing device tree flow.
* Make the i2c drivers stop calling `dev_pm_set_wake_irq` since it's now
  handled by the i2c core.
* Make the ACPI device PM system aware of the wake_irq. This is
  necessary so the device doesn't incorrectly get powered down when a
  wake_irq is enabled.

I've tested this code with various combinations of having _PRW,
ExclusiveAndWake and power resources all defined or not defined, but it
would be great if others could test this out on their hardware.

I'm sure this will surface some devices where the IRQs were not
correctly marked as wake capable. Ideally the firmware can be fixed, but
if not we can work around this in the kernel by providing a board
specific `struct i2c_board_info` with the `I2C_CLIENT_WAKE` flag set.
See `chromeos_laptop.c` for an example of matching DMI properties and
setting the `I2C_CLIENT_WAKE` override.

Thanks,
Raul

Changes in v2:
- Added elants_i2c to series
- Added raydium_ts_i2c to series
- Fixed call site in mlxbf_gige_probe
- Added ability to extract wake bit from Interrupt/IRQ resources
- Look at wake_cabple bit for IRQ/Interrupt resources
- I chose not to keep the legacy code around since systems without DT or ACPI should be rare.

Raul E Rangel (13):
  HID: i2c-hid: Use PM subsystem to manage wake irq
  Input: elan_i2c - Use PM subsystem to manage wake irq
  Input: elants_i2c - Use PM subsystem to manage wake irq
  Input: raydium_ts_i2c - Use PM subsystem to manage wake irq
  gpiolib: acpi: Add wake_capable parameter to acpi_dev_gpio_irq_get_by
  ACPI: resources: Add wake_capable parameter to acpi_dev_irq_flags
  i2c: acpi: Use ACPI wake capability bit to set wake_irq
  ACPI: PM: Take wake IRQ into consideration when entering
    suspend-to-idle
  HID: i2c-hid: acpi: Stop setting wakeup_capable
  HID: i2c-hid: Don't set wake_capable and wake_irq
  Input: elan_i2c - Don't set wake_capable and wake_irq
  Input: elants_i2c - Don't set wake_capable and wake_irq
  Input: raydium_ts_i2c - Don't set wake_capable and wake_irq

 drivers/acpi/device_pm.c                      | 19 +++++++++-
 drivers/acpi/irq.c                            | 11 ++++--
 drivers/acpi/resource.c                       | 24 ++++++++----
 drivers/gpio/gpio-pca953x.c                   |  3 +-
 drivers/gpio/gpiolib-acpi.c                   | 11 +++++-
 drivers/gpio/gpiolib-acpi.h                   |  2 +
 drivers/hid/i2c-hid/i2c-hid-acpi.c            |  5 ---
 drivers/hid/i2c-hid/i2c-hid-core.c            | 24 ++----------
 drivers/i2c/i2c-core-acpi.c                   | 37 ++++++++++++++-----
 drivers/i2c/i2c-core-base.c                   |  6 ++-
 drivers/i2c/i2c-core.h                        |  4 +-
 drivers/input/mouse/elan_i2c_core.c           | 15 +-------
 drivers/input/touchscreen/elants_i2c.c        | 13 +------
 drivers/input/touchscreen/raydium_i2c_ts.c    |  7 +---
 .../mellanox/mlxbf_gige/mlxbf_gige_main.c     |  3 +-
 drivers/pnp/pnpacpi/rsparser.c                |  9 +++--
 include/linux/acpi.h                          | 17 +++++++--
 include/linux/ioport.h                        |  3 +-
 18 files changed, 121 insertions(+), 92 deletions(-)

-- 
2.37.2.789.g6183377224-goog

The ACPI spec defines the SharedAndWake and ExclusiveAndWake share type
keywords. This is an indication that the GPIO IRQ can also be used as a
wake source. This change exposes the wake_capable bit so drivers can
correctly enable wake functionality instead of making an assumption.

Signed-off-by: Raul E Rangel <redacted>
---

Changes in v2:
- Fixed call site in mlxbf_gige_probe

 drivers/gpio/gpio-pca953x.c                        |  3 ++-
 drivers/gpio/gpiolib-acpi.c                        | 11 ++++++++++-
 drivers/gpio/gpiolib-acpi.h                        |  2 ++
 .../ethernet/mellanox/mlxbf_gige/mlxbf_gige_main.c |  3 ++-
 include/linux/acpi.h                               | 14 +++++++++++---
 5 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
index ecd7d169470b06..df02c3eb34a294 100644
--- a/drivers/gpio/gpio-pca953x.c
+++ b/drivers/gpio/gpio-pca953x.c

@@ -130,7 +130,8 @@ static int pca953x_acpi_get_irq(struct device *dev)
 	if (ret)
 		dev_warn(dev, "can't add GPIO ACPI mapping\n");
 
-	ret = acpi_dev_gpio_irq_get_by(ACPI_COMPANION(dev), "irq-gpios", 0);
+	ret = acpi_dev_gpio_irq_get_by(ACPI_COMPANION(dev), "irq-gpios", 0,
+				       NULL);
 	if (ret < 0)
 		return ret;
 

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 9be1376f9a627f..5cda2fcf7f43df 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c

@@ -741,6 +741,7 @@ static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
 		lookup->info.pin_config = agpio->pin_config;
 		lookup->info.debounce = agpio->debounce_timeout;
 		lookup->info.gpioint = gpioint;
+		lookup->info.wake_capable = agpio->wake_capable;
 
 		/*
 		 * Polarity and triggering are only specified for GpioInt

@@ -991,6 +992,7 @@ struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
  * @adev: pointer to a ACPI device to get IRQ from
  * @name: optional name of GpioInt resource
  * @index: index of GpioInt resource (starting from %0)
+ * @wake_capable: Set to 1 if the IRQ is wake capable
  *
  * If the device has one or more GpioInt resources, this function can be
  * used to translate from the GPIO offset in the resource to the Linux IRQ

@@ -1002,9 +1004,13 @@ struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
  * The function takes optional @name parameter. If the resource has a property
  * name, then only those will be taken into account.
  *
+ * The GPIO is considered wake capable if GpioInt specifies SharedAndWake or
+ * ExclusiveAndWake.
+ *
  * Return: Linux IRQ number (> %0) on success, negative errno on failure.
  */
-int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name, int index)
+int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name,
+			     int index, int *wake_capable)
 {
 	int idx, i;
 	unsigned int irq_flags;

@@ -1061,6 +1067,9 @@ int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name, int ind
 				dev_dbg(&adev->dev, "IRQ %d already in use\n", irq);
 			}
 
+			if (wake_capable)
+				*wake_capable = info.wake_capable;
+
 			return irq;
 		}
 

diff --git a/drivers/gpio/gpiolib-acpi.h b/drivers/gpio/gpiolib-acpi.h
index e476558d947136..1ac6816839dbce 100644
--- a/drivers/gpio/gpiolib-acpi.h
+++ b/drivers/gpio/gpiolib-acpi.h

@@ -18,6 +18,7 @@ struct acpi_device;
  * @pin_config: pin bias as provided by ACPI
  * @polarity: interrupt polarity as provided by ACPI
  * @triggering: triggering type as provided by ACPI
+ * @wake_capable: wake capability as provided by ACPI
  * @debounce: debounce timeout as provided by ACPI
  * @quirks: Linux specific quirks as provided by struct acpi_gpio_mapping
  */

@@ -28,6 +29,7 @@ struct acpi_gpio_info {
 	int pin_config;
 	int polarity;
 	int triggering;
+	bool wake_capable;
 	unsigned int debounce;
 	unsigned int quirks;
 };

diff --git a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_main.c b/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_main.c
index b03e1c66bac0d9..fa38271718d9e7 100644
--- a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_main.c
+++ b/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_main.c

@@ -340,7 +340,8 @@ static int mlxbf_gige_probe(struct platform_device *pdev)
 	priv->rx_irq = platform_get_irq(pdev, MLXBF_GIGE_RECEIVE_PKT_INTR_IDX);
 	priv->llu_plu_irq = platform_get_irq(pdev, MLXBF_GIGE_LLU_PLU_INTR_IDX);
 
-	phy_irq = acpi_dev_gpio_irq_get_by(ACPI_COMPANION(&pdev->dev), "phy-gpios", 0);
+	phy_irq = acpi_dev_gpio_irq_get_by(ACPI_COMPANION(&pdev->dev),
+					   "phy-gpios", 0, NULL);
 	if (phy_irq < 0) {
 		dev_err(&pdev->dev, "Error getting PHY irq. Use polling instead");
 		phy_irq = PHY_POLL;

diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 6f64b2f3dc5479..7ee946758c5bcc 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h

@@ -1202,7 +1202,8 @@ bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
 				struct acpi_resource_gpio **agpio);
 bool acpi_gpio_get_io_resource(struct acpi_resource *ares,
 			       struct acpi_resource_gpio **agpio);
-int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name, int index);
+int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name,
+			     int index, int *wake_capable);
 #else
 static inline bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
 					      struct acpi_resource_gpio **agpio)

@@ -1215,7 +1216,8 @@ static inline bool acpi_gpio_get_io_resource(struct acpi_resource *ares,
 	return false;
 }
 static inline int acpi_dev_gpio_irq_get_by(struct acpi_device *adev,
-					   const char *name, int index)
+					   const char *name, int index,
+					   int *wake_capable)
 {
 	return -ENXIO;
 }

@@ -1223,7 +1225,13 @@ static inline int acpi_dev_gpio_irq_get_by(struct acpi_device *adev,
 
 static inline int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
 {
-	return acpi_dev_gpio_irq_get_by(adev, NULL, index);
+	return acpi_dev_gpio_irq_get_by(adev, NULL, index, NULL);
+}
+
+static inline int acpi_dev_gpio_irq_get_wake(struct acpi_device *adev,
+					     int index, int *wake_capable)
+{
+	return acpi_dev_gpio_irq_get_by(adev, NULL, index, wake_capable);
 }
 
 /* Device properties */

-- 
2.37.2.789.g6183377224-goog

On Mon, Sep 12, 2022 at 04:13:09PM -0600, Raul E Rangel wrote:

The ACPI spec defines the SharedAndWake and ExclusiveAndWake share type
keywords. This is an indication that the GPIO IRQ can also be used as a
wake source. This change exposes the wake_capable bit so drivers can
correctly enable wake functionality instead of making an assumption.

...

-	ret = acpi_dev_gpio_irq_get_by(ACPI_COMPANION(dev), "irq-gpios", 0);
+	ret = acpi_dev_gpio_irq_get_by(ACPI_COMPANION(dev), "irq-gpios", 0,
+				       NULL);
 	if (ret < 0)
 		return ret;

Looking at these changes, can't we first introduce

	int acpi_dev_gpio_irq_get_by_name(struct acpi_device *adev, const char *name);

convert users, and then add wake stuff to the basic function.
In such case you will make less invasive main part of the idea.

-- 
With Best Regards,
Andy Shevchenko

Hi,

On Mon, Sep 12, 2022 at 04:13:09PM -0600, Raul E Rangel wrote:

+int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name,
+			     int index, int *wake_capable)

Here too bool.

On Tue, Sep 13, 2022 at 11:55 PM Mika Westerberg
[off-list ref] wrote:

Hi,

On Mon, Sep 12, 2022 at 04:13:09PM -0600, Raul E Rangel wrote:

quoted

+int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name,
+                          int index, int *wake_capable)

Here too bool.

I've incorporated both of your suggestions. I instead added
`acpi_dev_gpio_irq_wake_get_by` as the basic function and left
`acpi_dev_gpio_irq_get_by` the same. THis way I don't have to update
any of the callers.