[PATCH v5 00/13] acpi: i2c: Use SharedAndWake and ExclusiveAndWake to enable wake irq

[PATCH v5 00/13] acpi: i2c: Use SharedAndWake and ExclusiveAndWake to enable wake irq

[Raul E Rangel]

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 v5:
- Added Acked-by: Benjamin Tissoires
- Removed clang-format white space changes
- Check irq return value before updating wake_capable pointer
- Go back to using adev->wakeup.flags.valid to keep the diff cleaner
- Fix a typo in comment

Changes in v4:
- Added Reviewed-by
- Reformatted with 96 char limit
- Added Reviewed-by
- Reformatted with 96 char limit
- Removed unnecessary !!
- Removed unrelated whitespace change
- Added Reviewed-by
- Renamed i2c_acpi_add_resource to i2c_acpi_add_irq_resource
- Expanded logic in i2c_acpi_add_i2c_resource to make it easier to read

Changes in v3:
- Kept `acpi_dev_gpio_irq_get_by` unchanged to avoid having to touch
  unrelated drivers.
- Converted wake_capable parameter to bool.
- Fixed bad indent
- Convert wake_capable to bool
- Only update wake_capable pointer once
- Move wake_capable local into local block

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 variants of acpi_dev_gpio_irq_get
  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                         |  8 +++--
 drivers/acpi/resource.c                    | 16 +++++++---
 drivers/gpio/gpiolib-acpi.c                | 15 +++++++--
 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 +---
 drivers/pnp/pnpacpi/rsparser.c             |  7 ++--
 include/linux/acpi.h                       | 23 +++++++++++---
 include/linux/ioport.h                     |  3 +-
 16 files changed, 112 insertions(+), 92 deletions(-)

-- 
2.37.3.968.ga6b4b080e4-goog

[PATCH v5 05/13] gpiolib: acpi: Add wake_capable variants of acpi_dev_gpio_irq_get

[Raul E Rangel]

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 <rrangel@chromium.org>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---

(no changes since v4)

Changes in v4:
- Added Reviewed-by
- Reformatted with 96 char limit

Changes in v3:
- Kept `acpi_dev_gpio_irq_get_by` unchanged to avoid having to touch
  unrelated drivers.
- Converted wake_capable parameter to bool.

Changes in v2:
- Fixed call site in mlxbf_gige_probe

 drivers/gpio/gpiolib-acpi.c | 15 ++++++++++++---
 drivers/gpio/gpiolib-acpi.h |  2 ++
 include/linux/acpi.h        | 21 +++++++++++++++++----
 3 files changed, 31 insertions(+), 7 deletions(-)

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 9be1376f9a627f..1f2ade475b36cb 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 == ACPI_WAKE_CAPABLE;
 
 		/*
 		 * Polarity and triggering are only specified for GpioInt
@@ -987,10 +988,11 @@ struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
 }
 
 /**
- * acpi_dev_gpio_irq_get_by() - Find GpioInt and translate it to Linux IRQ number
+ * acpi_dev_gpio_irq_wake_get_by() - Find GpioInt and translate it to Linux IRQ number
  * @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 true 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 the GpioInt resource 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_wake_get_by(struct acpi_device *adev, const char *name, int index,
+				  bool *wake_capable)
 {
 	int idx, i;
 	unsigned int irq_flags;
@@ -1061,13 +1067,16 @@ 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;
 		}
 
 	}
 	return -ENOENT;
 }
-EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get_by);
+EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_wake_get_by);
 
 static acpi_status
 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
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/include/linux/acpi.h b/include/linux/acpi.h
index 6f64b2f3dc5479..cd7371a5f2839b 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_wake_get_by(struct acpi_device *adev, const char *name, int index,
+				  bool *wake_capable);
 #else
 static inline bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
 					      struct acpi_resource_gpio **agpio)
@@ -1214,16 +1215,28 @@ 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)
+static inline int acpi_dev_gpio_irq_wake_get_by(struct acpi_device *adev, const char *name,
+						int index, bool *wake_capable)
 {
 	return -ENXIO;
 }
 #endif
 
+static inline int acpi_dev_gpio_irq_wake_get(struct acpi_device *adev, int index,
+					     bool *wake_capable)
+{
+	return acpi_dev_gpio_irq_wake_get_by(adev, NULL, index, wake_capable);
+}
+
+static inline int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name,
+					   int index)
+{
+	return acpi_dev_gpio_irq_wake_get_by(adev, name, index, NULL);
+}
+
 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_wake_get_by(adev, NULL, index, NULL);
 }
 
 /* Device properties */
-- 
2.37.3.968.ga6b4b080e4-goog

Re: [PATCH v5 00/13] acpi: i2c: Use SharedAndWake and ExclusiveAndWake to enable wake irq

[Dmitry Torokhov]

On Wed, Sep 21, 2022 at 09:51:52AM -0600, Raul E Rangel wrote:
> 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.

How do we want to land this? I see there are a few acked-by/reviewed-by
already, should I take it through the input tree?

Thanks.

-- 
Dmitry

Re: [PATCH v5 00/13] acpi: i2c: Use SharedAndWake and ExclusiveAndWake to enable wake irq

[Andy Shevchenko]

On Wed, Sep 21, 2022 at 09:51:52AM -0600, Raul E Rangel wrote:
> 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 v5:
> - Added Acked-by: Benjamin Tissoires
> - Removed clang-format white space changes
> - Check irq return value before updating wake_capable pointer

You are too fast with a new versions... I have comment on the v4 and I believe
it applicable here (not settled yet).

> - Go back to using adev->wakeup.flags.valid to keep the diff cleaner
> - Fix a typo in comment
> 
> Changes in v4:
> - Added Reviewed-by
> - Reformatted with 96 char limit
> - Added Reviewed-by
> - Reformatted with 96 char limit
> - Removed unnecessary !!
> - Removed unrelated whitespace change
> - Added Reviewed-by
> - Renamed i2c_acpi_add_resource to i2c_acpi_add_irq_resource
> - Expanded logic in i2c_acpi_add_i2c_resource to make it easier to read
> 
> Changes in v3:
> - Kept `acpi_dev_gpio_irq_get_by` unchanged to avoid having to touch
>   unrelated drivers.
> - Converted wake_capable parameter to bool.
> - Fixed bad indent
> - Convert wake_capable to bool
> - Only update wake_capable pointer once
> - Move wake_capable local into local block
> 
> 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 variants of acpi_dev_gpio_irq_get
>   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                         |  8 +++--
>  drivers/acpi/resource.c                    | 16 +++++++---
>  drivers/gpio/gpiolib-acpi.c                | 15 +++++++--
>  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 +---
>  drivers/pnp/pnpacpi/rsparser.c             |  7 ++--
>  include/linux/acpi.h                       | 23 +++++++++++---
>  include/linux/ioport.h                     |  3 +-
>  16 files changed, 112 insertions(+), 92 deletions(-)
> 
> -- 
> 2.37.3.968.ga6b4b080e4-goog
> 

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v5 00/13] acpi: i2c: Use SharedAndWake and ExclusiveAndWake to enable wake irq

[Raul Rangel]

On Thu, Sep 22, 2022 at 4:16 AM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
>
> On Wed, Sep 21, 2022 at 09:51:52AM -0600, Raul E Rangel wrote:
> > 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 v5:
> > - Added Acked-by: Benjamin Tissoires
> > - Removed clang-format white space changes
> > - Check irq return value before updating wake_capable pointer
>

> You are too fast with a new versions... I have comment on the v4 and I believe
> it applicable here (not settled yet).
>

I'll send out a new series with the change.

> > - Go back to using adev->wakeup.flags.valid to keep the diff cleaner
> > - Fix a typo in comment
> >
> > Changes in v4:
> > - Added Reviewed-by
> > - Reformatted with 96 char limit
> > - Added Reviewed-by
> > - Reformatted with 96 char limit
> > - Removed unnecessary !!
> > - Removed unrelated whitespace change
> > - Added Reviewed-by
> > - Renamed i2c_acpi_add_resource to i2c_acpi_add_irq_resource
> > - Expanded logic in i2c_acpi_add_i2c_resource to make it easier to read
> >
> > Changes in v3:
> > - Kept `acpi_dev_gpio_irq_get_by` unchanged to avoid having to touch
> >   unrelated drivers.
> > - Converted wake_capable parameter to bool.
> > - Fixed bad indent
> > - Convert wake_capable to bool
> > - Only update wake_capable pointer once
> > - Move wake_capable local into local block
> >
> > 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 variants of acpi_dev_gpio_irq_get
> >   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                         |  8 +++--
> >  drivers/acpi/resource.c                    | 16 +++++++---
> >  drivers/gpio/gpiolib-acpi.c                | 15 +++++++--
> >  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 +---
> >  drivers/pnp/pnpacpi/rsparser.c             |  7 ++--
> >  include/linux/acpi.h                       | 23 +++++++++++---
> >  include/linux/ioport.h                     |  3 +-
> >  16 files changed, 112 insertions(+), 92 deletions(-)
> >
> > --
> > 2.37.3.968.ga6b4b080e4-goog
> >
>
> --
> With Best Regards,
> Andy Shevchenko
>
>